#
# Tcl package index file
#
# Note sqlite*3* init specifically
#
package ifneeded sqlite3 3.40.0 \
    [list load libtclsqlite3[info sharedlibextension] Sqlite3]

	-DSQLITE_HAVE_ZLIB=1 \
	-DSQLITE_ALLOW_ROWID_IN_VIEW=1 \
	-DHAVE_USLEEP=1 \
	-DHAVE_MREMAP=1 \
	-DHAVE_ISNAN=1 \
	-DU_LIB_SUFFIX_C_NAME=_sqlite3 \
	-DPACKAGE_NAME="\"sqlite\"" \
	-DPACKAGE_VERSION="\"3.40.0\"" \
	-DBUILD_sqlite=1 \
	-Dmain=sqlite3_shell \
	-O2

LOCAL_SHARED_LIBRARIES := libtcl

LOCAL_LDLIBS :=	-llog -lz

** This file contains code to implement the "sqlite" command line
** utility for accessing SQLite databases.
*/
#if (defined(_WIN32) || defined(WIN32)) && !defined(_CRT_SECURE_NO_WARNINGS)
/* This needs to come before any includes for MSVC compiler */
#define _CRT_SECURE_NO_WARNINGS
#endif
typedef unsigned int u32;
typedef unsigned short int u16;

/*
** Optionally #include a user-defined header, whereby compilation options
** may be set prior to where they take effect, but after platform setup. 
** If SQLITE_CUSTOM_INCLUDE=? is defined, its value names the #include
** file. Note that this macro has a like effect on sqlite3.c compilation.
*/
# define SHELL_STRINGIFY_(f) #f
# define SHELL_STRINGIFY(f) SHELL_STRINGIFY_(f)
#ifdef SQLITE_CUSTOM_INCLUDE
# include SHELL_STRINGIFY(SQLITE_CUSTOM_INCLUDE)
#endif

/*
** Determine if we are dealing with WinRT, which provides only a subset of
** the full Win32 API.
*/
#if !defined(SQLITE_OS_WINRT)
# define SQLITE_OS_WINRT 0
#endif

/*
** If SQLITE_SHELL_FIDDLE is defined then the shell is modified
** somewhat for use as a WASM module in a web browser. This flag
** should only be used when building the "fiddle" web application, as
** the browser-mode build has much different user input requirements
** and this build mode rewires the user input subsystem to account for
** that.
*/

/*
** Warning pragmas copied from msvc.h in the core.
*/
#if defined(_MSC_VER)
#pragma warning(disable : 4054)
#pragma warning(disable : 4055)

#ifndef SQLITE_DISABLE_LFS
# define _LARGE_FILE       1
# ifndef _FILE_OFFSET_BITS
#   define _FILE_OFFSET_BITS 64
# endif
# define _LARGEFILE_SOURCE 1
#endif

#if defined(SQLITE_SHELL_FIDDLE) && !defined(_POSIX_SOURCE)
/*
** emcc requires _POSIX_SOURCE (or one of several similar defines)
** to expose strdup().
*/
# define _POSIX_SOURCE
#endif

#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <assert.h>
#include "sqlite3.h"
typedef sqlite3_int64 i64;

  _setmode(_fileno(file), _O_TEXT);
}
#else
# define setBinaryMode(X,Y)
# define setTextMode(X,Y)
#endif

/* True if the timer is enabled */
static int enableTimer = 0;

/* A version of strcmp() that works with NULL values */
static int cli_strcmp(const char *a, const char *b){
  if( a==0 ) a = "";



  if( b==0 ) b = "";
  return strcmp(a,b);
}

static int cli_strncmp(const char *a, const char *b, size_t n){
  if( a==0 ) a = "";
  if( b==0 ) b = "";
  return strncmp(a,b,n);
}

/* Return the current wall-clock time */
static sqlite3_int64 timeOfDay(void){
  static sqlite3_vfs *clockVfs = 0;
  sqlite3_int64 t;
  if( clockVfs==0 ) clockVfs = sqlite3_vfs_find(0);
  if( clockVfs==0 ) return 0;  /* Never actually happens */

** in bytes.  This is different from the %*.*s specification in printf
** since with %*.*s the width is measured in bytes, not characters.
*/
static void utf8_width_print(FILE *pOut, int w, const char *zUtf){
  int i;
  int n;
  int aw = w<0 ? -w : w;
  if( zUtf==0 ) zUtf = "";
  for(i=n=0; zUtf[i]; i++){
    if( (zUtf[i]&0xc0)!=0x80 ){
      n++;
      if( n==aw ){
        do{ i++; }while( (zUtf[i]&0xc0)==0x80 );
        break;
      }

  }
#if defined(_WIN32) || defined(WIN32)
  /* For interactive input on Windows systems, translate the
  ** multi-byte characterset characters into UTF-8. */
  if( stdin_is_interactive && in==stdin ){
    char *zTrans = sqlite3_win32_mbcs_to_utf8_v2(zLine, 0);
    if( zTrans ){
      i64 nTrans = strlen(zTrans)+1;
      if( nTrans>nLine ){
        zLine = realloc(zLine, nTrans);
        shell_check_oom(zLine);
      }
      memcpy(zLine, zTrans, nTrans);
      sqlite3_free(zTrans);
    }

** If zPrior is not NULL then it is a buffer from a prior call to this
** routine that can be reused.
**
** The result is stored in space obtained from malloc() and must either
** be freed by the caller or else passed back into this routine via the
** zPrior argument for reuse.
*/
#ifndef SQLITE_SHELL_FIDDLE
static char *one_input_line(FILE *in, char *zPrior, int isContinuation){
  char *zPrompt;
  char *zResult;
  if( in!=0 ){
    zResult = local_getline(zPrior, in);
  }else{
    zPrompt = isContinuation ? continuePrompt : mainPrompt;
#if SHELL_USE_LOCAL_GETLINE
    printf("%s", zPrompt);
    fflush(stdout);
    zResult = local_getline(zPrior, stdin);
#else
    free(zPrior);
    zResult = shell_readline(zPrompt);
    if( zResult && *zResult ) shell_add_history(zResult);
#endif
  }
  return zResult;
}
#endif /* !SQLITE_SHELL_FIDDLE */

/*
** Return the value of a hexadecimal digit.  Return -1 if the input
** is not a hex digit.
*/
static int hexDigitValue(char c){
  if( c>='0' && c<='9' ) return c - '0';

** added to zIn, and the result returned in memory obtained from malloc().
** zIn, if it was not NULL, is freed.
**
** If the third argument, quote, is not '\0', then it is used as a
** quote character for zAppend.
*/
static void appendText(ShellText *p, const char *zAppend, char quote){
  i64 len;
  i64 i;
  i64 nAppend = strlen30(zAppend);

  len = nAppend+p->n+1;
  if( quote ){
    len += 2;
    for(i=0; i<nAppend; i++){
      if( zAppend[i]==quote ) len++;
    }

  };
  int i = 0;
  const char *zIn = (const char*)sqlite3_value_text(apVal[0]);
  const char *zSchema = (const char*)sqlite3_value_text(apVal[1]);
  const char *zName = (const char*)sqlite3_value_text(apVal[2]);
  sqlite3 *db = sqlite3_context_db_handle(pCtx);
  UNUSED_PARAMETER(nVal);
  if( zIn!=0 && cli_strncmp(zIn, "CREATE ", 7)==0 ){
    for(i=0; i<ArraySize(aPrefix); i++){
      int n = strlen30(aPrefix[i]);
      if( cli_strncmp(zIn+7, aPrefix[i], n)==0 && zIn[n+7]==' ' ){
        char *z = 0;
        char *zFake = 0;
        if( zSchema ){
          char cQuote = quoteChar(zSchema);
          if( cQuote && sqlite3_stricmp(zSchema,"temp")!=0 ){
            z = sqlite3_mprintf("%.*s \"%w\".%s", n+7, zIn, zSchema, zIn+n+8);
          }else{

*/
#define re_match   sqlite3re_match
#define re_compile sqlite3re_compile
#define re_free    sqlite3re_free

/* The end-of-input character */
#define RE_EOF            0    /* End of input */
#define RE_START  0xfffffff    /* Start of input - larger than an UTF-8 */

/* The NFA is implemented as sequence of opcodes taken from the following
** set.  Each opcode has a single integer argument.
*/
#define RE_OP_MATCH       1    /* Match the one character in the argument */
#define RE_OP_ANY         2    /* Match any one character.  (Implements ".") */
#define RE_OP_ANYSTAR     3    /* Special optimized version of .* */

#define RE_OP_WORD       11    /* Perl word character [A-Za-z0-9_] */
#define RE_OP_NOTWORD    12    /* Not a perl word character */
#define RE_OP_DIGIT      13    /* digit:  [0-9] */
#define RE_OP_NOTDIGIT   14    /* Not a digit */
#define RE_OP_SPACE      15    /* space:  [ \t\n\r\v\f] */
#define RE_OP_NOTSPACE   16    /* Not a digit */
#define RE_OP_BOUNDARY   17    /* Boundary between word and non-word */
#define RE_OP_ATSTART    18    /* Currently at the start of the string */

#if defined(SQLITE_DEBUG)
/* Opcode names used for symbolic debugging */
static const char *ReOpName[] = {
  "EOF",
  "MATCH",
  "ANY",
  "ANYSTAR",
  "FORK",
  "GOTO",
  "ACCEPT",
  "CC_INC",
  "CC_EXC",
  "CC_VALUE",
  "CC_RANGE",
  "WORD",
  "NOTWORD",
  "DIGIT",
  "NOTDIGIT",
  "SPACE",
  "NOTSPACE",
  "BOUNDARY",
  "ATSTART",
};
#endif /* SQLITE_DEBUG */


/* Each opcode is a "state" in the NFA */
typedef unsigned short ReStateNumber;

/* Because this is an NFA and not a DFA, multiple states can be active at
** once.  An instance of the following object records all active states in
** the NFA.  The implementation is optimized for the common case where the

struct ReCompiled {
  ReInput sIn;                /* Regular expression text */
  const char *zErr;           /* Error message to return */
  char *aOp;                  /* Operators for the virtual machine */
  int *aArg;                  /* Arguments to each operator */
  unsigned (*xNextChar)(ReInput*);  /* Next character function */
  unsigned char zInit[12];    /* Initial text to match */
  int nInit;                  /* Number of bytes in zInit */
  unsigned nState;            /* Number of entries in aOp[] and aArg[] */
  unsigned nAlloc;            /* Slots allocated for aOp[] and aArg[] */
};

/* Add a state to the given state set if it is not already there */
static void re_add_state(ReStateSet *pSet, int newState){
  unsigned i;

*/
static int re_match(ReCompiled *pRe, const unsigned char *zIn, int nIn){
  ReStateSet aStateSet[2], *pThis, *pNext;
  ReStateNumber aSpace[100];
  ReStateNumber *pToFree;
  unsigned int i = 0;
  unsigned int iSwap = 0;
  int c = RE_START;
  int cPrev = 0;
  int rc = 0;
  ReInput in;

  in.z = zIn;
  in.i = 0;
  in.mx = nIn>=0 ? nIn : (int)strlen((char const*)zIn);

  /* Look for the initial prefix match, if there is one. */
  if( pRe->nInit ){
    unsigned char x = pRe->zInit[0];
    while( in.i+pRe->nInit<=in.mx 
     && (zIn[in.i]!=x ||
         strncmp((const char*)zIn+in.i, (const char*)pRe->zInit, pRe->nInit)!=0)
    ){
      in.i++;
    }
    if( in.i+pRe->nInit>in.mx ) return 0;
    c = RE_START-1;
  }

  if( pRe->nState<=(sizeof(aSpace)/(sizeof(aSpace[0])*2)) ){
    pToFree = 0;
    aStateSet[0].aState = aSpace;
  }else{
    pToFree = sqlite3_malloc64( sizeof(ReStateNumber)*2*pRe->nState );

    pNext->nState = 0;
    for(i=0; i<pThis->nState; i++){
      int x = pThis->aState[i];
      switch( pRe->aOp[x] ){
        case RE_OP_MATCH: {
          if( pRe->aArg[x]==c ) re_add_state(pNext, x+1);
          break;
        }
        case RE_OP_ATSTART: {
          if( cPrev==RE_START ) re_add_state(pThis, x+1);
          break;
        }
        case RE_OP_ANY: {
          if( c!=0 ) re_add_state(pNext, x+1);
          break;
        }
        case RE_OP_WORD: {
          if( re_word_char(c) ) re_add_state(pNext, x+1);

          if( hit ) re_add_state(pNext, x+n);
          break;
        }
      }
    }
  }
  for(i=0; i<pNext->nState; i++){
    int x = pNext->aState[i];
    while( pRe->aOp[x]==RE_OP_GOTO ) x += pRe->aArg[x];
    if( pRe->aOp[x]==RE_OP_ACCEPT ){ rc = 1; break; }
  }
re_match_end:
  sqlite3_free(pToFree);
  return rc;
}

/* Resize the opcode and argument arrays for an RE under construction.

  int iStart;
  unsigned c;
  const char *zErr;
  while( (c = p->xNextChar(&p->sIn))!=0 ){
    iStart = p->nState;
    switch( c ){
      case '|':

      case ')': {
        p->sIn.i--;
        return 0;
      }
      case '(': {
        zErr = re_subcompile_re(p);
        if( zErr ) return zErr;

        re_append(p, RE_OP_FORK, iPrev - p->nState);
        break;
      }
      case '?': {
        if( iPrev<0 ) return "'?' without operand";
        re_insert(p, iPrev, RE_OP_FORK, p->nState - iPrev+1);
        break;
      }
      case '$': {
        re_append(p, RE_OP_MATCH, RE_EOF);
        break;
      }
      case '^': {
        re_append(p, RE_OP_ATSTART, 0);
        break;
      }
      case '{': {
        int m = 0, n = 0;
        int sz, j;
        if( iPrev<0 ) return "'{m,n}' without operand";
        while( (c=rePeek(p))>='0' && c<='9' ){ m = m*10 + c - '0'; p->sIn.i++; }
        n = m;
        if( c==',' ){
          p->sIn.i++;
          n = 0;
          while( (c=rePeek(p))>='0' && c<='9' ){ n = n*10 + c-'0'; p->sIn.i++; }
        }
        if( c!='}' ) return "unmatched '{'";
        if( n>0 && n<m ) return "n less than m in '{m,n}'";
        p->sIn.i++;
        sz = p->nState - iPrev;
        if( m==0 ){
          if( n==0 ) return "both m and n are zero in '{m,n}'";
          re_insert(p, iPrev, RE_OP_FORK, sz+1);
          iPrev++;
          n--;
        }else{
          for(j=1; j<m; j++) re_copy(p, iPrev, sz);
        }
        for(j=m; j<n; j++){
          re_append(p, RE_OP_FORK, sz+1);
          re_copy(p, iPrev, sz);

  pRe->sIn.i = 0;
  pRe->sIn.mx = (int)strlen(zIn);
  zErr = re_subcompile_re(pRe);
  if( zErr ){
    re_free(pRe);
    return zErr;
  }




  if( pRe->sIn.i>=pRe->sIn.mx ){
    re_append(pRe, RE_OP_ACCEPT, 0);
    *ppRe = pRe;
  }else{
    re_free(pRe);
    return "unrecognized character";
  }

  if( zStr!=0 ){
    sqlite3_result_int(context, re_match(pRe, zStr, -1));
  }
  if( setAux ){
    sqlite3_set_auxdata(context, 0, pRe, (void(*)(void*))re_free);
  }
}

#if defined(SQLITE_DEBUG)
/*
** This function is used for testing and debugging only.  It is only available
** if the SQLITE_DEBUG compile-time option is used.
**
** Compile a regular expression and then convert the compiled expression into
** text and return that text.
*/
static void re_bytecode_func(
  sqlite3_context *context,
  int argc,
  sqlite3_value **argv
){
  const char *zPattern;
  const char *zErr;
  ReCompiled *pRe;
  sqlite3_str *pStr;
  int i;
  int n;
  char *z;

  zPattern = (const char*)sqlite3_value_text(argv[0]);
  if( zPattern==0 ) return;
  zErr = re_compile(&pRe, zPattern, sqlite3_user_data(context)!=0);
  if( zErr ){
    re_free(pRe);
    sqlite3_result_error(context, zErr, -1);
    return;
  }
  if( pRe==0 ){
    sqlite3_result_error_nomem(context);
    return;
  }
  pStr = sqlite3_str_new(0);
  if( pStr==0 ) goto re_bytecode_func_err;
  if( pRe->nInit>0 ){
    sqlite3_str_appendf(pStr, "INIT     ");
    for(i=0; i<pRe->nInit; i++){
      sqlite3_str_appendf(pStr, "%02x", pRe->zInit[i]);
    }
    sqlite3_str_appendf(pStr, "\n");
  }
  for(i=0; (unsigned)i<pRe->nState; i++){
    sqlite3_str_appendf(pStr, "%-8s %4d\n",
         ReOpName[(unsigned char)pRe->aOp[i]], pRe->aArg[i]);
  }
  n = sqlite3_str_length(pStr);
  z = sqlite3_str_finish(pStr);
  if( n==0 ){
    sqlite3_free(z);
  }else{
    sqlite3_result_text(context, z, n-1, sqlite3_free);
  }

re_bytecode_func_err:
  re_free(pRe);
}

#endif /* SQLITE_DEBUG */


/*
** Invoke this routine to register the regexp() function with the
** SQLite database connection.
*/
#ifdef _WIN32

                            0, re_sql_func, 0, 0);
  if( rc==SQLITE_OK ){
    /* The regexpi(PATTERN,STRING) function is a case-insensitive version
    ** of regexp(PATTERN,STRING). */
    rc = sqlite3_create_function(db, "regexpi", 2,
                            SQLITE_UTF8|SQLITE_INNOCUOUS|SQLITE_DETERMINISTIC,
                            (void*)db, re_sql_func, 0, 0);
#if defined(SQLITE_DEBUG)
    if( rc==SQLITE_OK ){
      rc = sqlite3_create_function(db, "regexp_bytecode", 1,
                            SQLITE_UTF8|SQLITE_INNOCUOUS|SQLITE_DETERMINISTIC,
                            0, re_bytecode_func, 0, 0);
    }
#endif /* SQLITE_DEBUG */
  }
  return rc;
}

/************************* End ../ext/misc/regexp.c ********************/
#ifndef SQLITE_SHELL_FIDDLE
/************************* Begin ../ext/misc/fileio.c ******************/
/*
** 2014-06-13
**
** The author disclaims copyright to this source code.  In place of
** a legal notice, here is a blessing:
**

#  define UINT16_TYPE uint16_t
# else
#  define UINT16_TYPE unsigned short int
# endif
#endif
/* typedef sqlite3_int64 i64; */
/* typedef unsigned char u8; */
/* typedef UINT32_TYPE u32;           // 4-byte unsigned integer // */
/* typedef UINT16_TYPE u16;           // 2-byte unsigned integer // */
#define MIN(a,b) ((a)<(b) ? (a) : (b))

#if defined(SQLITE_COVERAGE_TEST) || defined(SQLITE_MUTATION_TEST)
# define SQLITE_OMIT_AUXILIARY_SAFETY_CHECKS 1
#endif
#if defined(SQLITE_OMIT_AUXILIARY_SAFETY_CHECKS)
# define ALWAYS(X)      (1)

/*
** Return true if zId must be quoted in order to use it as an SQL
** identifier, or false otherwise.
*/
static int idxIdentifierRequiresQuotes(const char *zId){
  int i;
  int nId = STRLEN(zId);
  
  if( sqlite3_keyword_check(zId, nId) ) return 1;

  for(i=0; zId[i]; i++){
    if( !(zId[i]=='_')
     && !(zId[i]>='0' && zId[i]<='9')
     && !(zId[i]>='a' && zId[i]<='z')
     && !(zId[i]>='A' && zId[i]<='Z')
    ){
      return 1;

}

#endif /* ifndef SQLITE_OMIT_VIRTUALTABLE */

/************************* End ../ext/expert/sqlite3expert.c ********************/

#if !defined(SQLITE_OMIT_VIRTUALTABLE) && defined(SQLITE_ENABLE_DBPAGE_VTAB)
#define SQLITE_SHELL_HAVE_RECOVER 1
#else
#define SQLITE_SHELL_HAVE_RECOVER 0
#endif
#if SQLITE_SHELL_HAVE_RECOVER
/************************* Begin ../ext/recover/dbdata.c ******************/
/*
** 2019-04-17
**
** The author disclaims copyright to this source code.  In place of
** a legal notice, here is a blessing:
**
**    May you do good and not evil.

**       child INTEGER,
**       schema TEXT HIDDEN
**     );
**
**   It contains one entry for each b-tree pointer between a parent and
**   child page in the database.
*/

#if !defined(SQLITEINT_H) 
/* #include "sqlite3ext.h" */

/* typedef unsigned char u8; */
/* typedef unsigned int u32; */

#endif
SQLITE_EXTENSION_INIT1
#include <string.h>
#include <assert.h>

#ifndef SQLITE_OMIT_VIRTUALTABLE

#define DBDATA_PADDING_BYTES 100 

typedef struct DbdataTable DbdataTable;
typedef struct DbdataCursor DbdataCursor;

/* Cursor object */

  int iCell;                      /* Current cell number */
  int bOnePage;                   /* True to stop after one page */
  int szDb;
  sqlite3_int64 iRowid;

  /* Only for the sqlite_dbdata table */
  u8 *pRec;                       /* Buffer containing current record */
  sqlite3_int64 nRec;             /* Size of pRec[] in bytes */
  sqlite3_int64 nHdr;             /* Size of header in bytes */
  int iField;                     /* Current field number */
  u8 *pHdrPtr;
  u8 *pPtr;
  u32 enc;                        /* Text encoding */
  
  sqlite3_int64 iIntkey;          /* Integer key value */
};

/* Table object */
struct DbdataTable {
  sqlite3_vtab base;              /* Base class.  Must be first */

  sqlite3_free(pCsr);
  return SQLITE_OK;
}

/* 
** Utility methods to decode 16 and 32-bit big-endian unsigned integers. 
*/
static u32 get_uint16(unsigned char *a){
  return (a[0]<<8)|a[1];
}
static u32 get_uint32(unsigned char *a){
  return ((u32)a[0]<<24)
       | ((u32)a[1]<<16)
       | ((u32)a[2]<<8)
       | ((u32)a[3]);
}

/*
** Load page pgno from the database via the sqlite_dbpage virtual table.
** If successful, set (*ppPage) to point to a buffer containing the page
** data, (*pnPage) to the size of that buffer in bytes and return
** SQLITE_OK. In this case it is the responsibility of the caller to
** eventually free the buffer using sqlite3_free().
**
** Or, if an error occurs, set both (*ppPage) and (*pnPage) to 0 and
** return an SQLite error code.
*/
static int dbdataLoadPage(
  DbdataCursor *pCsr,             /* Cursor object */
  u32 pgno,                       /* Page number of page to load */
  u8 **ppPage,                    /* OUT: pointer to page buffer */
  int *pnPage                     /* OUT: Size of (*ppPage) in bytes */
){
  int rc2;
  int rc = SQLITE_OK;
  sqlite3_stmt *pStmt = pCsr->pStmt;

  *ppPage = 0;
  *pnPage = 0;
  if( pgno>0 ){
    sqlite3_bind_int64(pStmt, 2, pgno);
    if( SQLITE_ROW==sqlite3_step(pStmt) ){
      int nCopy = sqlite3_column_bytes(pStmt, 0);
      if( nCopy>0 ){
        u8 *pPage;
        pPage = (u8*)sqlite3_malloc64(nCopy + DBDATA_PADDING_BYTES);
        if( pPage==0 ){
          rc = SQLITE_NOMEM;
        }else{
          const u8 *pCopy = sqlite3_column_blob(pStmt, 0);
          memcpy(pPage, pCopy, nCopy);
          memset(&pPage[nCopy], 0, DBDATA_PADDING_BYTES);
        }
        *ppPage = pPage;
        *pnPage = nCopy;
      }
    }
    rc2 = sqlite3_reset(pStmt);
    if( rc==SQLITE_OK ) rc = rc2;
  }

  return rc;
}

/*
** Read a varint.  Put the value in *pVal and return the number of bytes.
*/
static int dbdataGetVarint(const u8 *z, sqlite3_int64 *pVal){
  sqlite3_uint64 u = 0;
  int i;
  for(i=0; i<8; i++){
    u = (u<<7) + (z[i]&0x7f);
    if( (z[i]&0x80)==0 ){ *pVal = (sqlite3_int64)u; return i+1; }
  }
  u = (u<<8) + (z[i]&0xff);
  *pVal = (sqlite3_int64)u;
  return 9;
}

/*
** Like dbdataGetVarint(), but set the output to 0 if it is less than 0
** or greater than 0xFFFFFFFF. This can be used for all varints in an
** SQLite database except for key values in intkey tables.
*/
static int dbdataGetVarintU32(const u8 *z, sqlite3_int64 *pVal){
  sqlite3_int64 val;
  int nRet = dbdataGetVarint(z, &val);
  if( val<0 || val>0xFFFFFFFF ) val = 0;
  *pVal = val;
  return nRet;
}

/*
** Return the number of bytes of space used by an SQLite value of type
** eType.
*/
static int dbdataValueBytes(int eType){
  switch( eType ){

/*
** Load a value of type eType from buffer pData and use it to set the
** result of context object pCtx.
*/
static void dbdataValue(
  sqlite3_context *pCtx, 
  u32 enc,
  int eType, 
  u8 *pData,
  sqlite3_int64 nData
){
  if( eType>=0 && dbdataValueBytes(eType)<=nData ){
    switch( eType ){
      case 0: 
      case 10: 
      case 11: 
        sqlite3_result_null(pCtx);

        }
        break;
      }
  
      default: {
        int n = ((eType-12) / 2);
        if( eType % 2 ){
          switch( enc ){
#ifndef SQLITE_OMIT_UTF16
            case SQLITE_UTF16BE:
              sqlite3_result_text16be(pCtx, (void*)pData, n, SQLITE_TRANSIENT);
              break;
            case SQLITE_UTF16LE:
              sqlite3_result_text16le(pCtx, (void*)pData, n, SQLITE_TRANSIENT);
              break;
#endif
            default:
              sqlite3_result_text(pCtx, (char*)pData, n, SQLITE_TRANSIENT);
              break;
          }
        }else{
          sqlite3_result_blob(pCtx, pData, n, SQLITE_TRANSIENT);
        }
      }
    }
  }
}

    if( pCsr->aPage==0 ){
      while( 1 ){
        if( pCsr->bOnePage==0 && pCsr->iPgno>pCsr->szDb ) return SQLITE_OK;
        rc = dbdataLoadPage(pCsr, pCsr->iPgno, &pCsr->aPage, &pCsr->nPage);
        if( rc!=SQLITE_OK ) return rc;
        if( pCsr->aPage ) break;
        if( pCsr->bOnePage ) return SQLITE_OK;
        pCsr->iPgno++;
      }
      pCsr->iCell = pTab->bPtr ? -2 : 0;
      pCsr->nCell = get_uint16(&pCsr->aPage[iOff+3]);
    }

    if( pTab->bPtr ){

          /* For an interior node cell, skip past the child-page number */
          iOff += nPointer;
    
          /* Load the "byte of payload including overflow" field */
          if( bNextPage || iOff>pCsr->nPage ){
            bNextPage = 1;
          }else{
            iOff += dbdataGetVarintU32(&pCsr->aPage[iOff], &nPayload);
          }
    
          /* If this is a leaf intkey cell, load the rowid */
          if( bHasRowid && !bNextPage && iOff<pCsr->nPage ){
            iOff += dbdataGetVarint(&pCsr->aPage[iOff], &pCsr->iIntkey);
          }
    

            /* Load the nLocal bytes of payload */
            memcpy(pCsr->pRec, &pCsr->aPage[iOff], nLocal);
            iOff += nLocal;

            /* Load content from overflow pages */
            if( nPayload>nLocal ){
              sqlite3_int64 nRem = nPayload - nLocal;
              u32 pgnoOvfl = get_uint32(&pCsr->aPage[iOff]);
              while( nRem>0 ){
                u8 *aOvfl = 0;
                int nOvfl = 0;
                int nCopy;
                rc = dbdataLoadPage(pCsr, pgnoOvfl, &aOvfl, &nOvfl);
                assert( rc!=SQLITE_OK || aOvfl==0 || nOvfl==pCsr->nPage );
                if( rc!=SQLITE_OK ) return rc;
                if( aOvfl==0 ) break;

                nCopy = U-4;
                if( nCopy>nRem ) nCopy = nRem;
                memcpy(&pCsr->pRec[nPayload-nRem], &aOvfl[4], nCopy);
                nRem -= nCopy;

                pgnoOvfl = get_uint32(aOvfl);
                sqlite3_free(aOvfl);
              }
            }
    
            iHdr = dbdataGetVarintU32(pCsr->pRec, &nHdr);
            if( nHdr>nPayload ) nHdr = 0;
            pCsr->nHdr = nHdr;
            pCsr->pHdrPtr = &pCsr->pRec[iHdr];
            pCsr->pPtr = &pCsr->pRec[pCsr->nHdr];
            pCsr->iField = (bHasRowid ? -1 : 0);
          }
        }
      }else{
        pCsr->iField++;
        if( pCsr->iField>0 ){
          sqlite3_int64 iType;
          if( pCsr->pHdrPtr>&pCsr->pRec[pCsr->nRec] ){
            bNextPage = 1;
          }else{
            pCsr->pHdrPtr += dbdataGetVarintU32(pCsr->pHdrPtr, &iType);
            pCsr->pPtr += dbdataValueBytes(iType);
          }
        }
      }

      if( bNextPage ){
        sqlite3_free(pCsr->aPage);

/* 
** Return true if the cursor is at EOF.
*/
static int dbdataEof(sqlite3_vtab_cursor *pCursor){
  DbdataCursor *pCsr = (DbdataCursor*)pCursor;
  return pCsr->aPage==0;
}

/*
** Return true if nul-terminated string zSchema ends in "()". Or false
** otherwise.
*/
static int dbdataIsFunction(const char *zSchema){
  size_t n = strlen(zSchema);
  if( n>2 && zSchema[n-2]=='(' && zSchema[n-1]==')' ){
    return (int)n-2;
  }
  return 0;
}

/* 
** Determine the size in pages of database zSchema (where zSchema is
** "main", "temp" or the name of an attached database) and set 
** pCsr->szDb accordingly. If successful, return SQLITE_OK. Otherwise,
** an SQLite error code.
*/
static int dbdataDbsize(DbdataCursor *pCsr, const char *zSchema){
  DbdataTable *pTab = (DbdataTable*)pCsr->base.pVtab;
  char *zSql = 0;
  int rc, rc2;
  int nFunc = 0;
  sqlite3_stmt *pStmt = 0;

  if( (nFunc = dbdataIsFunction(zSchema))>0 ){
    zSql = sqlite3_mprintf("SELECT %.*s(0)", nFunc, zSchema);
  }else{
    zSql = sqlite3_mprintf("PRAGMA %Q.page_count", zSchema);
  }
  if( zSql==0 ) return SQLITE_NOMEM;

  rc = sqlite3_prepare_v2(pTab->db, zSql, -1, &pStmt, 0);
  sqlite3_free(zSql);
  if( rc==SQLITE_OK && sqlite3_step(pStmt)==SQLITE_ROW ){
    pCsr->szDb = sqlite3_column_int(pStmt, 0);
  }
  rc2 = sqlite3_finalize(pStmt);
  if( rc==SQLITE_OK ) rc = rc2;
  return rc;
}

/*
** Attempt to figure out the encoding of the database by retrieving page 1
** and inspecting the header field. If successful, set the pCsr->enc variable
** and return SQLITE_OK. Otherwise, return an SQLite error code.
*/
static int dbdataGetEncoding(DbdataCursor *pCsr){
  int rc = SQLITE_OK;
  int nPg1 = 0;
  u8 *aPg1 = 0;
  rc = dbdataLoadPage(pCsr, 1, &aPg1, &nPg1);
  assert( rc!=SQLITE_OK || nPg1==0 || nPg1>=512 );
  if( rc==SQLITE_OK && nPg1>0 ){
    pCsr->enc = get_uint32(&aPg1[56]);
  }
  sqlite3_free(aPg1);
  return rc;
}


/* 
** xFilter method for sqlite_dbdata and sqlite_dbptr.
*/
static int dbdataFilter(
  sqlite3_vtab_cursor *pCursor, 
  int idxNum, const char *idxStr,
  int argc, sqlite3_value **argv
){
  DbdataCursor *pCsr = (DbdataCursor*)pCursor;
  DbdataTable *pTab = (DbdataTable*)pCursor->pVtab;
  int rc = SQLITE_OK;
  const char *zSchema = "main";

  dbdataResetCursor(pCsr);
  assert( pCsr->iPgno==1 );
  if( idxNum & 0x01 ){
    zSchema = (const char*)sqlite3_value_text(argv[0]);
    if( zSchema==0 ) zSchema = "";
  }
  if( idxNum & 0x02 ){
    pCsr->iPgno = sqlite3_value_int(argv[(idxNum & 0x01)]);
    pCsr->bOnePage = 1;
  }else{

    rc = dbdataDbsize(pCsr, zSchema);
  }

  if( rc==SQLITE_OK ){
    int nFunc = 0;
    if( pTab->pStmt ){
      pCsr->pStmt = pTab->pStmt;
      pTab->pStmt = 0;
    }else if( (nFunc = dbdataIsFunction(zSchema))>0 ){
      char *zSql = sqlite3_mprintf("SELECT %.*s(?2)", nFunc, zSchema);
      if( zSql==0 ){
        rc = SQLITE_NOMEM;
      }else{
        rc = sqlite3_prepare_v2(pTab->db, zSql, -1, &pCsr->pStmt, 0);
        sqlite3_free(zSql);
      }
    }else{
      rc = sqlite3_prepare_v2(pTab->db, 
          "SELECT data FROM sqlite_dbpage(?) WHERE pgno=?", -1,
          &pCsr->pStmt, 0
      );
    }
  }
  if( rc==SQLITE_OK ){
    rc = sqlite3_bind_text(pCsr->pStmt, 1, zSchema, -1, SQLITE_TRANSIENT);
  }else{
    pTab->base.zErrMsg = sqlite3_mprintf("%s", sqlite3_errmsg(pTab->db));
  }

  /* Try to determine the encoding of the db by inspecting the header
  ** field on page 1. */
  if( rc==SQLITE_OK ){
    rc = dbdataGetEncoding(pCsr);
  }

  if( rc==SQLITE_OK ){
    rc = dbdataNext(pCursor);
  }
  return rc;
}

/*
** Return a column for the sqlite_dbdata or sqlite_dbptr table.
*/
static int dbdataColumn(
  sqlite3_vtab_cursor *pCursor, 
  sqlite3_context *ctx, 
  int i
){

        break;
      case DBDATA_COLUMN_FIELD:
        sqlite3_result_int(ctx, pCsr->iField);
        break;
      case DBDATA_COLUMN_VALUE: {
        if( pCsr->iField<0 ){
          sqlite3_result_int64(ctx, pCsr->iIntkey);
        }else if( &pCsr->pRec[pCsr->nRec] >= pCsr->pPtr ){
          sqlite3_int64 iType;
          dbdataGetVarintU32(pCsr->pHdrPtr, &iType);
          dbdataValue(
              ctx, pCsr->enc, iType, pCsr->pPtr, 
              &pCsr->pRec[pCsr->nRec] - pCsr->pPtr
          );
        }
        break;
      }
    }
  }
  return SQLITE_OK;

  char **pzErrMsg, 
  const sqlite3_api_routines *pApi
){
  SQLITE_EXTENSION_INIT2(pApi);
  return sqlite3DbdataRegister(db);
}

#endif /* ifndef SQLITE_OMIT_VIRTUALTABLE */

/************************* End ../ext/recover/dbdata.c ********************/
/************************* Begin ../ext/recover/sqlite3recover.h ******************/
/*
** 2022-08-27
**
** The author disclaims copyright to this source code.  In place of
** a legal notice, here is a blessing:
**
**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
**
** This file contains the public interface to the "recover" extension -
** an SQLite extension designed to recover data from corrupted database
** files.
*/

/*
** OVERVIEW:
**
** To use the API to recover data from a corrupted database, an
** application:
**
**   1) Creates an sqlite3_recover handle by calling either
**      sqlite3_recover_init() or sqlite3_recover_init_sql().
**
**   2) Configures the new handle using one or more calls to
**      sqlite3_recover_config().
**
**   3) Executes the recovery by repeatedly calling sqlite3_recover_step() on
**      the handle until it returns something other than SQLITE_OK. If it
**      returns SQLITE_DONE, then the recovery operation completed without 
**      error. If it returns some other non-SQLITE_OK value, then an error 
**      has occurred.
**
**   4) Retrieves any error code and English language error message using the
**      sqlite3_recover_errcode() and sqlite3_recover_errmsg() APIs,
**      respectively.
**
**   5) Destroys the sqlite3_recover handle and frees all resources
**      using sqlite3_recover_finish().
**
** The application may abandon the recovery operation at any point 
** before it is finished by passing the sqlite3_recover handle to
** sqlite3_recover_finish(). This is not an error, but the final state
** of the output database, or the results of running the partial script
** delivered to the SQL callback, are undefined.
*/

#ifndef _SQLITE_RECOVER_H
#define _SQLITE_RECOVER_H

/* #include "sqlite3.h" */

#ifdef __cplusplus
extern "C" {
#endif

/*
** An instance of the sqlite3_recover object represents a recovery
** operation in progress.
**
** Constructors:
**
**    sqlite3_recover_init()
**    sqlite3_recover_init_sql()
**
** Destructor:
**
**    sqlite3_recover_finish()
**
** Methods:
**
**    sqlite3_recover_config()
**    sqlite3_recover_errcode()
**    sqlite3_recover_errmsg()
**    sqlite3_recover_run()
**    sqlite3_recover_step()
*/
typedef struct sqlite3_recover sqlite3_recover;

/* 
** These two APIs attempt to create and return a new sqlite3_recover object.
** In both cases the first two arguments identify the (possibly
** corrupt) database to recover data from. The first argument is an open
** database handle and the second the name of a database attached to that
** handle (i.e. "main", "temp" or the name of an attached database).
**
** If sqlite3_recover_init() is used to create the new sqlite3_recover
** handle, then data is recovered into a new database, identified by
** string parameter zUri. zUri may be an absolute or relative file path,
** or may be an SQLite URI. If the identified database file already exists,
** it is overwritten.
**
** If sqlite3_recover_init_sql() is invoked, then any recovered data will
** be returned to the user as a series of SQL statements. Executing these
** SQL statements results in the same database as would have been created
** had sqlite3_recover_init() been used. For each SQL statement in the
** output, the callback function passed as the third argument (xSql) is 
** invoked once. The first parameter is a passed a copy of the fourth argument
** to this function (pCtx) as its first parameter, and a pointer to a
** nul-terminated buffer containing the SQL statement formated as UTF-8 as 
** the second. If the xSql callback returns any value other than SQLITE_OK,
** then processing is immediately abandoned and the value returned used as
** the recover handle error code (see below).
**
** If an out-of-memory error occurs, NULL may be returned instead of
** a valid handle. In all other cases, it is the responsibility of the
** application to avoid resource leaks by ensuring that
** sqlite3_recover_finish() is called on all allocated handles.
*/
sqlite3_recover *sqlite3_recover_init(
  sqlite3* db, 
  const char *zDb, 
  const char *zUri
);
sqlite3_recover *sqlite3_recover_init_sql(
  sqlite3* db, 
  const char *zDb, 
  int (*xSql)(void*, const char*),
  void *pCtx
);

/*
** Configure an sqlite3_recover object that has just been created using
** sqlite3_recover_init() or sqlite3_recover_init_sql(). This function
** may only be called before the first call to sqlite3_recover_step()
** or sqlite3_recover_run() on the object.
**
** The second argument passed to this function must be one of the
** SQLITE_RECOVER_* symbols defined below. Valid values for the third argument
** depend on the specific SQLITE_RECOVER_* symbol in use.
**
** SQLITE_OK is returned if the configuration operation was successful,
** or an SQLite error code otherwise.
*/
int sqlite3_recover_config(sqlite3_recover*, int op, void *pArg);

/*
** SQLITE_RECOVER_LOST_AND_FOUND:
**   The pArg argument points to a string buffer containing the name
**   of a "lost-and-found" table in the output database, or NULL. If
**   the argument is non-NULL and the database contains seemingly
**   valid pages that cannot be associated with any table in the
**   recovered part of the schema, data is extracted from these
**   pages to add to the lost-and-found table.
**
** SQLITE_RECOVER_FREELIST_CORRUPT:
**   The pArg value must actually be a pointer to a value of type
**   int containing value 0 or 1 cast as a (void*). If this option is set
**   (argument is 1) and a lost-and-found table has been configured using
**   SQLITE_RECOVER_LOST_AND_FOUND, then is assumed that the freelist is 
**   corrupt and an attempt is made to recover records from pages that
**   appear to be linked into the freelist. Otherwise, pages on the freelist
**   are ignored. Setting this option can recover more data from the
**   database, but often ends up "recovering" deleted records. The default 
**   value is 0 (clear).
**
** SQLITE_RECOVER_ROWIDS:
**   The pArg value must actually be a pointer to a value of type
**   int containing value 0 or 1 cast as a (void*). If this option is set
**   (argument is 1), then an attempt is made to recover rowid values
**   that are not also INTEGER PRIMARY KEY values. If this option is
**   clear, then new rowids are assigned to all recovered rows. The
**   default value is 1 (set).
**
** SQLITE_RECOVER_SLOWINDEXES:
**   The pArg value must actually be a pointer to a value of type
**   int containing value 0 or 1 cast as a (void*). If this option is clear
**   (argument is 0), then when creating an output database, the recover 
**   module creates and populates non-UNIQUE indexes right at the end of the
**   recovery operation - after all recoverable data has been inserted
**   into the new database. This is faster overall, but means that the
**   final call to sqlite3_recover_step() for a recovery operation may
**   be need to create a large number of indexes, which may be very slow.
**
**   Or, if this option is set (argument is 1), then non-UNIQUE indexes
**   are created in the output database before it is populated with 
**   recovered data. This is slower overall, but avoids the slow call
**   to sqlite3_recover_step() at the end of the recovery operation.
**
**   The default option value is 0.
*/
#define SQLITE_RECOVER_LOST_AND_FOUND   1
#define SQLITE_RECOVER_FREELIST_CORRUPT 2
#define SQLITE_RECOVER_ROWIDS           3
#define SQLITE_RECOVER_SLOWINDEXES      4

/*
** Perform a unit of work towards the recovery operation. This function 
** must normally be called multiple times to complete database recovery.
**
** If no error occurs but the recovery operation is not completed, this
** function returns SQLITE_OK. If recovery has been completed successfully
** then SQLITE_DONE is returned. If an error has occurred, then an SQLite
** error code (e.g. SQLITE_IOERR or SQLITE_NOMEM) is returned. It is not
** considered an error if some or all of the data cannot be recovered
** due to database corruption.
**
** Once sqlite3_recover_step() has returned a value other than SQLITE_OK,
** all further such calls on the same recover handle are no-ops that return
** the same non-SQLITE_OK value.
*/
int sqlite3_recover_step(sqlite3_recover*);

/* 
** Run the recovery operation to completion. Return SQLITE_OK if successful,
** or an SQLite error code otherwise. Calling this function is the same
** as executing:
**
**     while( SQLITE_OK==sqlite3_recover_step(p) );
**     return sqlite3_recover_errcode(p);
*/
int sqlite3_recover_run(sqlite3_recover*);

/*
** If an error has been encountered during a prior call to
** sqlite3_recover_step(), then this function attempts to return a 
** pointer to a buffer containing an English language explanation of 
** the error. If no error message is available, or if an out-of memory 
** error occurs while attempting to allocate a buffer in which to format
** the error message, NULL is returned.
**
** The returned buffer remains valid until the sqlite3_recover handle is
** destroyed using sqlite3_recover_finish().
*/
const char *sqlite3_recover_errmsg(sqlite3_recover*);

/*
** If this function is called on an sqlite3_recover handle after
** an error occurs, an SQLite error code is returned. Otherwise, SQLITE_OK.
*/
int sqlite3_recover_errcode(sqlite3_recover*);

/* 
** Clean up a recovery object created by a call to sqlite3_recover_init().
** The results of using a recovery object with any API after it has been
** passed to this function are undefined.
**
** This function returns the same value as sqlite3_recover_errcode().
*/
int sqlite3_recover_finish(sqlite3_recover*);


#ifdef __cplusplus
}  /* end of the 'extern "C"' block */
#endif

#endif /* ifndef _SQLITE_RECOVER_H */

/************************* End ../ext/recover/sqlite3recover.h ********************/
/************************* Begin ../ext/recover/sqlite3recover.c ******************/
/*
** 2022-08-27
**
** The author disclaims copyright to this source code.  In place of
** a legal notice, here is a blessing:
**
**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
**
*/


/* #include "sqlite3recover.h" */
#include <assert.h>
#include <string.h>

#ifndef SQLITE_OMIT_VIRTUALTABLE

/*
** Declaration for public API function in file dbdata.c. This may be called
** with NULL as the final two arguments to register the sqlite_dbptr and
** sqlite_dbdata virtual tables with a database handle.
*/
#ifdef _WIN32

#endif
int sqlite3_dbdata_init(sqlite3*, char**, const sqlite3_api_routines*);

/* typedef unsigned int u32; */
/* typedef unsigned char u8; */
/* typedef sqlite3_int64 i64; */

typedef struct RecoverTable RecoverTable;
typedef struct RecoverColumn RecoverColumn;

/*
** When recovering rows of data that can be associated with table
** definitions recovered from the sqlite_schema table, each table is
** represented by an instance of the following object.
**
** iRoot:
**   The root page in the original database. Not necessarily (and usually
**   not) the same in the recovered database.
**
** zTab:
**   Name of the table.
**
** nCol/aCol[]:
**   aCol[] is an array of nCol columns. In the order in which they appear 
**   in the table.
**
** bIntkey:
**   Set to true for intkey tables, false for WITHOUT ROWID.
**
** iRowidBind:
**   Each column in the aCol[] array has associated with it the index of
**   the bind parameter its values will be bound to in the INSERT statement
**   used to construct the output database. If the table does has a rowid
**   but not an INTEGER PRIMARY KEY column, then iRowidBind contains the
**   index of the bind paramater to which the rowid value should be bound.
**   Otherwise, it contains -1. If the table does contain an INTEGER PRIMARY 
**   KEY column, then the rowid value should be bound to the index associated
**   with the column.
**
** pNext:
**   All RecoverTable objects used by the recovery operation are allocated
**   and populated as part of creating the recovered database schema in
**   the output database, before any non-schema data are recovered. They
**   are then stored in a singly-linked list linked by this variable beginning
**   at sqlite3_recover.pTblList.
*/
struct RecoverTable {
  u32 iRoot;                      /* Root page in original database */
  char *zTab;                     /* Name of table */
  int nCol;                       /* Number of columns in table */
  RecoverColumn *aCol;            /* Array of columns */
  int bIntkey;                    /* True for intkey, false for without rowid */
  int iRowidBind;                 /* If >0, bind rowid to INSERT here */
  RecoverTable *pNext;
};

/*
** Each database column is represented by an instance of the following object
** stored in the RecoverTable.aCol[] array of the associated table.
**
** iField:
**   The index of the associated field within database records. Or -1 if
**   there is no associated field (e.g. for virtual generated columns).
**
** iBind:
**   The bind index of the INSERT statement to bind this columns values
**   to. Or 0 if there is no such index (iff (iField<0)).
**
** bIPK:
**   True if this is the INTEGER PRIMARY KEY column.
**
** zCol:
**   Name of column.
**
** eHidden:
**   A RECOVER_EHIDDEN_* constant value (see below for interpretation of each).
*/
struct RecoverColumn {
  int iField;                     /* Field in record on disk */
  int iBind;                      /* Binding to use in INSERT */
  int bIPK;                       /* True for IPK column */
  char *zCol;
  int eHidden;
};

#define RECOVER_EHIDDEN_NONE    0      /* Normal database column */
#define RECOVER_EHIDDEN_HIDDEN  1      /* Column is __HIDDEN__ */
#define RECOVER_EHIDDEN_VIRTUAL 2      /* Virtual generated column */
#define RECOVER_EHIDDEN_STORED  3      /* Stored generated column */

/*
** Bitmap object used to track pages in the input database. Allocated
** and manipulated only by the following functions:
**
**     recoverBitmapAlloc()
**     recoverBitmapFree()
**     recoverBitmapSet()
**     recoverBitmapQuery()
**
** nPg:
**   Largest page number that may be stored in the bitmap. The range
**   of valid keys is 1 to nPg, inclusive.
**
** aElem[]:
**   Array large enough to contain a bit for each key. For key value
**   iKey, the associated bit is the bit (iKey%32) of aElem[iKey/32].
**   In other words, the following is true if bit iKey is set, or 
**   false if it is clear:
**
**       (aElem[iKey/32] & (1 << (iKey%32))) ? 1 : 0
*/
typedef struct RecoverBitmap RecoverBitmap;
struct RecoverBitmap {
  i64 nPg;                        /* Size of bitmap */
  u32 aElem[1];                   /* Array of 32-bit bitmasks */
};

/*
** State variables (part of the sqlite3_recover structure) used while
** recovering data for tables identified in the recovered schema (state
** RECOVER_STATE_WRITING).
*/
typedef struct RecoverStateW1 RecoverStateW1;
struct RecoverStateW1 {
  sqlite3_stmt *pTbls;
  sqlite3_stmt *pSel;
  sqlite3_stmt *pInsert;
  int nInsert;

  RecoverTable *pTab;             /* Table currently being written */
  int nMax;                       /* Max column count in any schema table */
  sqlite3_value **apVal;          /* Array of nMax values */
  int nVal;                       /* Number of valid entries in apVal[] */
  int bHaveRowid;
  i64 iRowid;
  i64 iPrevPage;
  int iPrevCell;
};

/*
** State variables (part of the sqlite3_recover structure) used while
** recovering data destined for the lost and found table (states
** RECOVER_STATE_LOSTANDFOUND[123]).
*/
typedef struct RecoverStateLAF RecoverStateLAF;
struct RecoverStateLAF {
  RecoverBitmap *pUsed;
  i64 nPg;                        /* Size of db in pages */
  sqlite3_stmt *pAllAndParent;
  sqlite3_stmt *pMapInsert;
  sqlite3_stmt *pMaxField;
  sqlite3_stmt *pUsedPages;
  sqlite3_stmt *pFindRoot;
  sqlite3_stmt *pInsert;          /* INSERT INTO lost_and_found ... */
  sqlite3_stmt *pAllPage;
  sqlite3_stmt *pPageData;
  sqlite3_value **apVal;
  int nMaxField;
};

/*
** Main recover handle structure.
*/
struct sqlite3_recover {
  /* Copies of sqlite3_recover_init[_sql]() parameters */
  sqlite3 *dbIn;                  /* Input database */
  char *zDb;                      /* Name of input db ("main" etc.) */
  char *zUri;                     /* URI for output database */
  void *pSqlCtx;                  /* SQL callback context */
  int (*xSql)(void*,const char*); /* Pointer to SQL callback function */

  /* Values configured by sqlite3_recover_config() */
  char *zStateDb;                 /* State database to use (or NULL) */
  char *zLostAndFound;            /* Name of lost-and-found table (or NULL) */
  int bFreelistCorrupt;           /* SQLITE_RECOVER_FREELIST_CORRUPT setting */
  int bRecoverRowid;              /* SQLITE_RECOVER_ROWIDS setting */
  int bSlowIndexes;               /* SQLITE_RECOVER_SLOWINDEXES setting */

  int pgsz;
  int detected_pgsz;
  int nReserve;
  u8 *pPage1Disk;
  u8 *pPage1Cache;

  /* Error code and error message */
  int errCode;                    /* For sqlite3_recover_errcode() */
  char *zErrMsg;                  /* For sqlite3_recover_errmsg() */

  int eState;
  int bCloseTransaction;

  /* Variables used with eState==RECOVER_STATE_WRITING */
  RecoverStateW1 w1;

  /* Variables used with states RECOVER_STATE_LOSTANDFOUND[123] */
  RecoverStateLAF laf;

  /* Fields used within sqlite3_recover_run() */
  sqlite3 *dbOut;                 /* Output database */
  sqlite3_stmt *pGetPage;         /* SELECT against input db sqlite_dbdata */
  RecoverTable *pTblList;         /* List of tables recovered from schema */
};

/*
** The various states in which an sqlite3_recover object may exist:
**
**   RECOVER_STATE_INIT:
**    The object is initially created in this state. sqlite3_recover_step()
**    has yet to be called. This is the only state in which it is permitted
**    to call sqlite3_recover_config().
**
**   RECOVER_STATE_WRITING:
**
**   RECOVER_STATE_LOSTANDFOUND1:
**    State to populate the bitmap of pages used by other tables or the
**    database freelist.
**
**   RECOVER_STATE_LOSTANDFOUND2:
**    Populate the recovery.map table - used to figure out a "root" page
**    for each lost page from in the database from which records are
**    extracted.
**
**   RECOVER_STATE_LOSTANDFOUND3:
**    Populate the lost-and-found table itself.
*/
#define RECOVER_STATE_INIT           0
#define RECOVER_STATE_WRITING        1
#define RECOVER_STATE_LOSTANDFOUND1  2
#define RECOVER_STATE_LOSTANDFOUND2  3
#define RECOVER_STATE_LOSTANDFOUND3  4
#define RECOVER_STATE_SCHEMA2        5
#define RECOVER_STATE_DONE           6


/*
** Global variables used by this extension.
*/
typedef struct RecoverGlobal RecoverGlobal;
struct RecoverGlobal {
  const sqlite3_io_methods *pMethods;
  sqlite3_recover *p;
};
static RecoverGlobal recover_g;

/*
** Use this static SQLite mutex to protect the globals during the
** first call to sqlite3_recover_step().
*/ 
#define RECOVER_MUTEX_ID SQLITE_MUTEX_STATIC_APP2


/* 
** Default value for SQLITE_RECOVER_ROWIDS (sqlite3_recover.bRecoverRowid).
*/
#define RECOVER_ROWID_DEFAULT 1

/*
** Mutex handling:
**
**    recoverEnterMutex()       -   Enter the recovery mutex
**    recoverLeaveMutex()       -   Leave the recovery mutex
**    recoverAssertMutexHeld()  -   Assert that the recovery mutex is held
*/
#if defined(SQLITE_THREADSAFE) && SQLITE_THREADSAFE==0
# define recoverEnterMutex()
# define recoverLeaveMutex()
#else
static void recoverEnterMutex(void){
  sqlite3_mutex_enter(sqlite3_mutex_alloc(RECOVER_MUTEX_ID));
}
static void recoverLeaveMutex(void){
  sqlite3_mutex_leave(sqlite3_mutex_alloc(RECOVER_MUTEX_ID));
}
#endif
#if SQLITE_THREADSAFE+0>=1 && defined(SQLITE_DEBUG)
static void recoverAssertMutexHeld(void){
  assert( sqlite3_mutex_held(sqlite3_mutex_alloc(RECOVER_MUTEX_ID)) );
}
#else
# define recoverAssertMutexHeld()
#endif


/*
** Like strlen(). But handles NULL pointer arguments.
*/
static int recoverStrlen(const char *zStr){
  if( zStr==0 ) return 0;
  return (int)(strlen(zStr)&0x7fffffff);
}

/*
** This function is a no-op if the recover handle passed as the first 
** argument already contains an error (if p->errCode!=SQLITE_OK). 
**
** Otherwise, an attempt is made to allocate, zero and return a buffer nByte
** bytes in size. If successful, a pointer to the new buffer is returned. Or,
** if an OOM error occurs, NULL is returned and the handle error code
** (p->errCode) set to SQLITE_NOMEM.
*/
static void *recoverMalloc(sqlite3_recover *p, i64 nByte){
  void *pRet = 0;
  assert( nByte>0 );
  if( p->errCode==SQLITE_OK ){
    pRet = sqlite3_malloc64(nByte);
    if( pRet ){
      memset(pRet, 0, nByte);
    }else{
      p->errCode = SQLITE_NOMEM;
    }
  }
  return pRet;
}

/*
** Set the error code and error message for the recover handle passed as
** the first argument. The error code is set to the value of parameter
** errCode.
**
** Parameter zFmt must be a printf() style formatting string. The handle 
** error message is set to the result of using any trailing arguments for 
** parameter substitutions in the formatting string.
**
** For example:
**
**   recoverError(p, SQLITE_ERROR, "no such table: %s", zTablename);
*/
static int recoverError(
  sqlite3_recover *p, 
  int errCode, 
  const char *zFmt, ...
){
  char *z = 0;
  va_list ap;
  va_start(ap, zFmt);
  if( zFmt ){
    z = sqlite3_vmprintf(zFmt, ap);
    va_end(ap);
  }
  sqlite3_free(p->zErrMsg);
  p->zErrMsg = z;
  p->errCode = errCode;
  return errCode;
}


/*
** This function is a no-op if p->errCode is initially other than SQLITE_OK.
** In this case it returns NULL.
**
** Otherwise, an attempt is made to allocate and return a bitmap object
** large enough to store a bit for all page numbers between 1 and nPg,
** inclusive. The bitmap is initially zeroed.
*/
static RecoverBitmap *recoverBitmapAlloc(sqlite3_recover *p, i64 nPg){
  int nElem = (nPg+1+31) / 32;
  int nByte = sizeof(RecoverBitmap) + nElem*sizeof(u32);
  RecoverBitmap *pRet = (RecoverBitmap*)recoverMalloc(p, nByte);

  if( pRet ){
    pRet->nPg = nPg;
  }
  return pRet;
}

/*
** Free a bitmap object allocated by recoverBitmapAlloc().
*/
static void recoverBitmapFree(RecoverBitmap *pMap){
  sqlite3_free(pMap);
}

/*
** Set the bit associated with page iPg in bitvec pMap.
*/
static void recoverBitmapSet(RecoverBitmap *pMap, i64 iPg){
  if( iPg<=pMap->nPg ){
    int iElem = (iPg / 32);
    int iBit = (iPg % 32);
    pMap->aElem[iElem] |= (((u32)1) << iBit);
  }
}

/*
** Query bitmap object pMap for the state of the bit associated with page
** iPg. Return 1 if it is set, or 0 otherwise.
*/
static int recoverBitmapQuery(RecoverBitmap *pMap, i64 iPg){
  int ret = 1;
  if( iPg<=pMap->nPg && iPg>0 ){
    int iElem = (iPg / 32);
    int iBit = (iPg % 32);
    ret = (pMap->aElem[iElem] & (((u32)1) << iBit)) ? 1 : 0;
  }
  return ret;
}

/*
** Set the recover handle error to the error code and message returned by
** calling sqlite3_errcode() and sqlite3_errmsg(), respectively, on database
** handle db.
*/
static int recoverDbError(sqlite3_recover *p, sqlite3 *db){
  return recoverError(p, sqlite3_errcode(db), "%s", sqlite3_errmsg(db));
}

/*
** This function is a no-op if recover handle p already contains an error
** (if p->errCode!=SQLITE_OK). 
**
** Otherwise, it attempts to prepare the SQL statement in zSql against
** database handle db. If successful, the statement handle is returned.
** Or, if an error occurs, NULL is returned and an error left in the
** recover handle.
*/
static sqlite3_stmt *recoverPrepare(
  sqlite3_recover *p,
  sqlite3 *db, 
  const char *zSql
){
  sqlite3_stmt *pStmt = 0;
  if( p->errCode==SQLITE_OK ){
    if( sqlite3_prepare_v2(db, zSql, -1, &pStmt, 0) ){
      recoverDbError(p, db);
    }
  }
  return pStmt;
}

/*
** This function is a no-op if recover handle p already contains an error
** (if p->errCode!=SQLITE_OK). 
**
** Otherwise, argument zFmt is used as a printf() style format string,
** along with any trailing arguments, to create an SQL statement. This
** SQL statement is prepared against database handle db and, if successful,
** the statment handle returned. Or, if an error occurs - either during
** the printf() formatting or when preparing the resulting SQL - an
** error code and message are left in the recover handle.
*/
static sqlite3_stmt *recoverPreparePrintf(
  sqlite3_recover *p,
  sqlite3 *db, 
  const char *zFmt, ...
){
  sqlite3_stmt *pStmt = 0;
  if( p->errCode==SQLITE_OK ){
    va_list ap;
    char *z;
    va_start(ap, zFmt);
    z = sqlite3_vmprintf(zFmt, ap);
    va_end(ap);
    if( z==0 ){
      p->errCode = SQLITE_NOMEM;
    }else{
      pStmt = recoverPrepare(p, db, z);
      sqlite3_free(z);
    }
  }
  return pStmt;
}

/*
** Reset SQLite statement handle pStmt. If the call to sqlite3_reset() 
** indicates that an error occurred, and there is not already an error
** in the recover handle passed as the first argument, set the error
** code and error message appropriately.
**
** This function returns a copy of the statement handle pointer passed
** as the second argument.
*/
static sqlite3_stmt *recoverReset(sqlite3_recover *p, sqlite3_stmt *pStmt){
  int rc = sqlite3_reset(pStmt);
  if( rc!=SQLITE_OK && rc!=SQLITE_CONSTRAINT && p->errCode==SQLITE_OK ){
    recoverDbError(p, sqlite3_db_handle(pStmt));
  }
  return pStmt;
}

/*
** Finalize SQLite statement handle pStmt. If the call to sqlite3_reset() 
** indicates that an error occurred, and there is not already an error
** in the recover handle passed as the first argument, set the error
** code and error message appropriately.
*/
static void recoverFinalize(sqlite3_recover *p, sqlite3_stmt *pStmt){
  sqlite3 *db = sqlite3_db_handle(pStmt);
  int rc = sqlite3_finalize(pStmt);
  if( rc!=SQLITE_OK && p->errCode==SQLITE_OK ){
    recoverDbError(p, db);
  }
}

/*
** This function is a no-op if recover handle p already contains an error
** (if p->errCode!=SQLITE_OK). A copy of p->errCode is returned in this 
** case.
**
** Otherwise, execute SQL script zSql. If successful, return SQLITE_OK.
** Or, if an error occurs, leave an error code and message in the recover
** handle and return a copy of the error code.
*/
static int recoverExec(sqlite3_recover *p, sqlite3 *db, const char *zSql){
  if( p->errCode==SQLITE_OK ){
    int rc = sqlite3_exec(db, zSql, 0, 0, 0);
    if( rc ){
      recoverDbError(p, db);
    }
  }
  return p->errCode;
}

/*
** Bind the value pVal to parameter iBind of statement pStmt. Leave an
** error in the recover handle passed as the first argument if an error
** (e.g. an OOM) occurs.
*/
static void recoverBindValue(
  sqlite3_recover *p, 
  sqlite3_stmt *pStmt, 
  int iBind, 
  sqlite3_value *pVal
){
  if( p->errCode==SQLITE_OK ){
    int rc = sqlite3_bind_value(pStmt, iBind, pVal);
    if( rc ) recoverError(p, rc, 0);
  }
}

/*
** This function is a no-op if recover handle p already contains an error
** (if p->errCode!=SQLITE_OK). NULL is returned in this case.
**
** Otherwise, an attempt is made to interpret zFmt as a printf() style
** formatting string and the result of using the trailing arguments for
** parameter substitution with it written into a buffer obtained from
** sqlite3_malloc(). If successful, a pointer to the buffer is returned.
** It is the responsibility of the caller to eventually free the buffer
** using sqlite3_free().
**
** Or, if an error occurs, an error code and message is left in the recover
** handle and NULL returned.
*/
static char *recoverMPrintf(sqlite3_recover *p, const char *zFmt, ...){
  va_list ap;
  char *z;
  va_start(ap, zFmt);
  z = sqlite3_vmprintf(zFmt, ap);
  va_end(ap);
  if( p->errCode==SQLITE_OK ){
    if( z==0 ) p->errCode = SQLITE_NOMEM;
  }else{
    sqlite3_free(z);
    z = 0;
  }
  return z;
}

/*
** This function is a no-op if recover handle p already contains an error
** (if p->errCode!=SQLITE_OK). Zero is returned in this case.
**
** Otherwise, execute "PRAGMA page_count" against the input database. If
** successful, return the integer result. Or, if an error occurs, leave an
** error code and error message in the sqlite3_recover handle and return
** zero.
*/
static i64 recoverPageCount(sqlite3_recover *p){
  i64 nPg = 0;
  if( p->errCode==SQLITE_OK ){
    sqlite3_stmt *pStmt = 0;
    pStmt = recoverPreparePrintf(p, p->dbIn, "PRAGMA %Q.page_count", p->zDb);
    if( pStmt ){
      sqlite3_step(pStmt);
      nPg = sqlite3_column_int64(pStmt, 0);
    }
    recoverFinalize(p, pStmt);
  }
  return nPg;
}

/*
** Implementation of SQL scalar function "read_i32". The first argument to 
** this function must be a blob. The second a non-negative integer. This 
** function reads and returns a 32-bit big-endian integer from byte
** offset (4*<arg2>) of the blob.
**
**     SELECT read_i32(<blob>, <idx>)
*/
static void recoverReadI32(
  sqlite3_context *context, 
  int argc, 
  sqlite3_value **argv
){
  const unsigned char *pBlob;
  int nBlob;
  int iInt;

  assert( argc==2 );
  nBlob = sqlite3_value_bytes(argv[0]);
  pBlob = (const unsigned char*)sqlite3_value_blob(argv[0]);
  iInt = sqlite3_value_int(argv[1]) & 0xFFFF;

  if( (iInt+1)*4<=nBlob ){
    const unsigned char *a = &pBlob[iInt*4];
    i64 iVal = ((i64)a[0]<<24)
             + ((i64)a[1]<<16)
             + ((i64)a[2]<< 8)
             + ((i64)a[3]<< 0);
    sqlite3_result_int64(context, iVal);
  }
}

/*
** Implementation of SQL scalar function "page_is_used". This function
** is used as part of the procedure for locating orphan rows for the
** lost-and-found table, and it depends on those routines having populated
** the sqlite3_recover.laf.pUsed variable.
**
** The only argument to this function is a page-number. It returns true 
** if the page has already been used somehow during data recovery, or false
** otherwise.
**
**     SELECT page_is_used(<pgno>);
*/
static void recoverPageIsUsed(
  sqlite3_context *pCtx,
  int nArg,
  sqlite3_value **apArg
){
  sqlite3_recover *p = (sqlite3_recover*)sqlite3_user_data(pCtx);
  i64 pgno = sqlite3_value_int64(apArg[0]);
  assert( nArg==1 );
  sqlite3_result_int(pCtx, recoverBitmapQuery(p->laf.pUsed, pgno));
}

/*
** The implementation of a user-defined SQL function invoked by the 
** sqlite_dbdata and sqlite_dbptr virtual table modules to access pages
** of the database being recovered.
**
** This function always takes a single integer argument. If the argument
** is zero, then the value returned is the number of pages in the db being
** recovered. If the argument is greater than zero, it is a page number. 
** The value returned in this case is an SQL blob containing the data for 
** the identified page of the db being recovered. e.g.
**
**     SELECT getpage(0);       -- return number of pages in db
**     SELECT getpage(4);       -- return page 4 of db as a blob of data 
*/
static void recoverGetPage(
  sqlite3_context *pCtx,
  int nArg,
  sqlite3_value **apArg
){
  sqlite3_recover *p = (sqlite3_recover*)sqlite3_user_data(pCtx);
  i64 pgno = sqlite3_value_int64(apArg[0]);
  sqlite3_stmt *pStmt = 0;

  assert( nArg==1 );
  if( pgno==0 ){
    i64 nPg = recoverPageCount(p);
    sqlite3_result_int64(pCtx, nPg);
    return;
  }else{
    if( p->pGetPage==0 ){
      pStmt = p->pGetPage = recoverPreparePrintf(
          p, p->dbIn, "SELECT data FROM sqlite_dbpage(%Q) WHERE pgno=?", p->zDb
      );
    }else if( p->errCode==SQLITE_OK ){
      pStmt = p->pGetPage;
    }

    if( pStmt ){
      sqlite3_bind_int64(pStmt, 1, pgno);
      if( SQLITE_ROW==sqlite3_step(pStmt) ){
        const u8 *aPg;
        int nPg;
        assert( p->errCode==SQLITE_OK );
        aPg = sqlite3_column_blob(pStmt, 0);
        nPg = sqlite3_column_bytes(pStmt, 0);
        if( pgno==1 && nPg==p->pgsz && 0==memcmp(p->pPage1Cache, aPg, nPg) ){
          aPg = p->pPage1Disk;
        }
        sqlite3_result_blob(pCtx, aPg, nPg-p->nReserve, SQLITE_TRANSIENT);
      }
      recoverReset(p, pStmt);
    }
  }

  if( p->errCode ){
    if( p->zErrMsg ) sqlite3_result_error(pCtx, p->zErrMsg, -1);
    sqlite3_result_error_code(pCtx, p->errCode);
  }
}

/*
** Find a string that is not found anywhere in z[].  Return a pointer
** to that string.
**
** Try to use zA and zB first.  If both of those are already found in z[]
** then make up some string and store it in the buffer zBuf.
*/
static const char *recoverUnusedString(
  const char *z,                    /* Result must not appear anywhere in z */
  const char *zA, const char *zB,   /* Try these first */
  char *zBuf                        /* Space to store a generated string */
){
  unsigned i = 0;
  if( strstr(z, zA)==0 ) return zA;
  if( strstr(z, zB)==0 ) return zB;
  do{
    sqlite3_snprintf(20,zBuf,"(%s%u)", zA, i++);
  }while( strstr(z,zBuf)!=0 );
  return zBuf;
}

/*
** Implementation of scalar SQL function "escape_crnl".  The argument passed to
** this function is the output of built-in function quote(). If the first
** character of the input is "'", indicating that the value passed to quote()
** was a text value, then this function searches the input for "\n" and "\r"
** characters and adds a wrapper similar to the following:
**
**   replace(replace(<input>, '\n', char(10), '\r', char(13));
**
** Or, if the first character of the input is not "'", then a copy of the input
** is returned.
*/
static void recoverEscapeCrnl(
  sqlite3_context *context, 
  int argc, 
  sqlite3_value **argv
){
  const char *zText = (const char*)sqlite3_value_text(argv[0]);
  if( zText && zText[0]=='\'' ){
    int nText = sqlite3_value_bytes(argv[0]);
    int i;
    char zBuf1[20];
    char zBuf2[20];
    const char *zNL = 0;
    const char *zCR = 0;
    int nCR = 0;
    int nNL = 0;

    for(i=0; zText[i]; i++){
      if( zNL==0 && zText[i]=='\n' ){
        zNL = recoverUnusedString(zText, "\\n", "\\012", zBuf1);
        nNL = (int)strlen(zNL);
      }
      if( zCR==0 && zText[i]=='\r' ){
        zCR = recoverUnusedString(zText, "\\r", "\\015", zBuf2);
        nCR = (int)strlen(zCR);
      }
    }

    if( zNL || zCR ){
      int iOut = 0;
      i64 nMax = (nNL > nCR) ? nNL : nCR;
      i64 nAlloc = nMax * nText + (nMax+64)*2;
      char *zOut = (char*)sqlite3_malloc64(nAlloc);
      if( zOut==0 ){
        sqlite3_result_error_nomem(context);
        return;
      }

      if( zNL && zCR ){
        memcpy(&zOut[iOut], "replace(replace(", 16);
        iOut += 16;
      }else{
        memcpy(&zOut[iOut], "replace(", 8);
        iOut += 8;
      }
      for(i=0; zText[i]; i++){
        if( zText[i]=='\n' ){
          memcpy(&zOut[iOut], zNL, nNL);
          iOut += nNL;
        }else if( zText[i]=='\r' ){
          memcpy(&zOut[iOut], zCR, nCR);
          iOut += nCR;
        }else{
          zOut[iOut] = zText[i];
          iOut++;
        }
      }

      if( zNL ){
        memcpy(&zOut[iOut], ",'", 2); iOut += 2;
        memcpy(&zOut[iOut], zNL, nNL); iOut += nNL;
        memcpy(&zOut[iOut], "', char(10))", 12); iOut += 12;
      }
      if( zCR ){
        memcpy(&zOut[iOut], ",'", 2); iOut += 2;
        memcpy(&zOut[iOut], zCR, nCR); iOut += nCR;
        memcpy(&zOut[iOut], "', char(13))", 12); iOut += 12;
      }

      sqlite3_result_text(context, zOut, iOut, SQLITE_TRANSIENT);
      sqlite3_free(zOut);
      return;
    }
  }

  sqlite3_result_value(context, argv[0]);
}

/*
** This function is a no-op if recover handle p already contains an error
** (if p->errCode!=SQLITE_OK). A copy of the error code is returned in
** this case. 
**
** Otherwise, attempt to populate temporary table "recovery.schema" with the
** parts of the database schema that can be extracted from the input database.
**
** If no error occurs, SQLITE_OK is returned. Otherwise, an error code
** and error message are left in the recover handle and a copy of the
** error code returned. It is not considered an error if part of all of
** the database schema cannot be recovered due to corruption.
*/
static int recoverCacheSchema(sqlite3_recover *p){
  return recoverExec(p, p->dbOut,
    "WITH RECURSIVE pages(p) AS ("
    "  SELECT 1"
    "    UNION"
    "  SELECT child FROM sqlite_dbptr('getpage()'), pages WHERE pgno=p"
    ")"
    "INSERT INTO recovery.schema SELECT"
    "  max(CASE WHEN field=0 THEN value ELSE NULL END),"
    "  max(CASE WHEN field=1 THEN value ELSE NULL END),"
    "  max(CASE WHEN field=2 THEN value ELSE NULL END),"
    "  max(CASE WHEN field=3 THEN value ELSE NULL END),"
    "  max(CASE WHEN field=4 THEN value ELSE NULL END)"
    "FROM sqlite_dbdata('getpage()') WHERE pgno IN ("
    "  SELECT p FROM pages"
    ") GROUP BY pgno, cell"
  );
}

/*
** If this recover handle is not in SQL callback mode (i.e. was not created 
** using sqlite3_recover_init_sql()) of if an error has already occurred, 
** this function is a no-op. Otherwise, issue a callback with SQL statement
** zSql as the parameter. 
**
** If the callback returns non-zero, set the recover handle error code to
** the value returned (so that the caller will abandon processing).
*/
static void recoverSqlCallback(sqlite3_recover *p, const char *zSql){
  if( p->errCode==SQLITE_OK && p->xSql ){
    int res = p->xSql(p->pSqlCtx, zSql);
    if( res ){
      recoverError(p, SQLITE_ERROR, "callback returned an error - %d", res);
    }
  }
}

/*
** Transfer the following settings from the input database to the output
** database:
**
**   + page-size,
**   + auto-vacuum settings,
**   + database encoding,
**   + user-version (PRAGMA user_version), and
**   + application-id (PRAGMA application_id), and
*/
static void recoverTransferSettings(sqlite3_recover *p){
  const char *aPragma[] = {
    "encoding",
    "page_size",
    "auto_vacuum",
    "user_version",
    "application_id"
  };
  int ii;

  /* Truncate the output database to 0 pages in size. This is done by 
  ** opening a new, empty, temp db, then using the backup API to clobber 
  ** any existing output db with a copy of it. */
  if( p->errCode==SQLITE_OK ){
    sqlite3 *db2 = 0;
    int rc = sqlite3_open("", &db2);
    if( rc!=SQLITE_OK ){
      recoverDbError(p, db2);
      return;
    }

    for(ii=0; ii<sizeof(aPragma)/sizeof(aPragma[0]); ii++){
      const char *zPrag = aPragma[ii];
      sqlite3_stmt *p1 = 0;
      p1 = recoverPreparePrintf(p, p->dbIn, "PRAGMA %Q.%s", p->zDb, zPrag);
      if( p->errCode==SQLITE_OK && sqlite3_step(p1)==SQLITE_ROW ){
        const char *zArg = (const char*)sqlite3_column_text(p1, 0);
        char *z2 = recoverMPrintf(p, "PRAGMA %s = %Q", zPrag, zArg);
        recoverSqlCallback(p, z2);
        recoverExec(p, db2, z2);
        sqlite3_free(z2);
        if( zArg==0 ){
          recoverError(p, SQLITE_NOMEM, 0);
        }
      }
      recoverFinalize(p, p1);
    }
    recoverExec(p, db2, "CREATE TABLE t1(a); DROP TABLE t1;");

    if( p->errCode==SQLITE_OK ){
      sqlite3 *db = p->dbOut;
      sqlite3_backup *pBackup = sqlite3_backup_init(db, "main", db2, "main");
      if( pBackup ){
        sqlite3_backup_step(pBackup, -1);
        p->errCode = sqlite3_backup_finish(pBackup);
      }else{
        recoverDbError(p, db);
      }
    }

    sqlite3_close(db2);
  }
}

/*
** This function is a no-op if recover handle p already contains an error
** (if p->errCode!=SQLITE_OK). A copy of the error code is returned in
** this case. 
**
** Otherwise, an attempt is made to open the output database, attach
** and create the schema of the temporary database used to store
** intermediate data, and to register all required user functions and
** virtual table modules with the output handle.
**
** If no error occurs, SQLITE_OK is returned. Otherwise, an error code
** and error message are left in the recover handle and a copy of the
** error code returned.
*/
static int recoverOpenOutput(sqlite3_recover *p){
  struct Func {
    const char *zName;
    int nArg;
    void (*xFunc)(sqlite3_context*,int,sqlite3_value **);
  } aFunc[] = {
    { "getpage", 1, recoverGetPage },
    { "page_is_used", 1, recoverPageIsUsed },
    { "read_i32", 2, recoverReadI32 },
    { "escape_crnl", 1, recoverEscapeCrnl },
  };

  const int flags = SQLITE_OPEN_URI|SQLITE_OPEN_CREATE|SQLITE_OPEN_READWRITE;
  sqlite3 *db = 0;                /* New database handle */
  int ii;                         /* For iterating through aFunc[] */

  assert( p->dbOut==0 );

  if( sqlite3_open_v2(p->zUri, &db, flags, 0) ){
    recoverDbError(p, db);
  }

  /* Register the sqlite_dbdata and sqlite_dbptr virtual table modules.
  ** These two are registered with the output database handle - this
  ** module depends on the input handle supporting the sqlite_dbpage
  ** virtual table only.  */
  if( p->errCode==SQLITE_OK ){
    p->errCode = sqlite3_dbdata_init(db, 0, 0);
  }

  /* Register the custom user-functions with the output handle. */
  for(ii=0; p->errCode==SQLITE_OK && ii<sizeof(aFunc)/sizeof(aFunc[0]); ii++){
    p->errCode = sqlite3_create_function(db, aFunc[ii].zName, 
        aFunc[ii].nArg, SQLITE_UTF8, (void*)p, aFunc[ii].xFunc, 0, 0
    );
  }

  p->dbOut = db;
  return p->errCode;
}

/*
** Attach the auxiliary database 'recovery' to the output database handle.
** This temporary database is used during the recovery process and then 
** discarded.
*/
static void recoverOpenRecovery(sqlite3_recover *p){
  char *zSql = recoverMPrintf(p, "ATTACH %Q AS recovery;", p->zStateDb);
  recoverExec(p, p->dbOut, zSql);
  recoverExec(p, p->dbOut,
      "PRAGMA writable_schema = 1;"
      "CREATE TABLE recovery.map(pgno INTEGER PRIMARY KEY, parent INT);" 
      "CREATE TABLE recovery.schema(type, name, tbl_name, rootpage, sql);"
  );
  sqlite3_free(zSql);
}


/*
** This function is a no-op if recover handle p already contains an error
** (if p->errCode!=SQLITE_OK).
**
** Otherwise, argument zName must be the name of a table that has just been
** created in the output database. This function queries the output db
** for the schema of said table, and creates a RecoverTable object to
** store the schema in memory. The new RecoverTable object is linked into
** the list at sqlite3_recover.pTblList.
**
** Parameter iRoot must be the root page of table zName in the INPUT 
** database.
*/
static void recoverAddTable(
  sqlite3_recover *p, 
  const char *zName,              /* Name of table created in output db */
  i64 iRoot                       /* Root page of same table in INPUT db */
){
  sqlite3_stmt *pStmt = recoverPreparePrintf(p, p->dbOut, 
      "PRAGMA table_xinfo(%Q)", zName
  );

  if( pStmt ){
    int iPk = -1;
    int iBind = 1;
    RecoverTable *pNew = 0;
    int nCol = 0;
    int nName = recoverStrlen(zName);
    int nByte = 0;
    while( sqlite3_step(pStmt)==SQLITE_ROW ){
      nCol++;
      nByte += (sqlite3_column_bytes(pStmt, 1)+1);
    }
    nByte += sizeof(RecoverTable) + nCol*sizeof(RecoverColumn) + nName+1;
    recoverReset(p, pStmt);

    pNew = recoverMalloc(p, nByte);
    if( pNew ){
      int i = 0;
      int iField = 0;
      char *csr = 0;
      pNew->aCol = (RecoverColumn*)&pNew[1];
      pNew->zTab = csr = (char*)&pNew->aCol[nCol];
      pNew->nCol = nCol;
      pNew->iRoot = iRoot;
      memcpy(csr, zName, nName);
      csr += nName+1;

      for(i=0; sqlite3_step(pStmt)==SQLITE_ROW; i++){
        int iPKF = sqlite3_column_int(pStmt, 5);
        int n = sqlite3_column_bytes(pStmt, 1);
        const char *z = (const char*)sqlite3_column_text(pStmt, 1);
        const char *zType = (const char*)sqlite3_column_text(pStmt, 2);
        int eHidden = sqlite3_column_int(pStmt, 6);

        if( iPk==-1 && iPKF==1 && !sqlite3_stricmp("integer", zType) ) iPk = i;
        if( iPKF>1 ) iPk = -2;
        pNew->aCol[i].zCol = csr;
        pNew->aCol[i].eHidden = eHidden;
        if( eHidden==RECOVER_EHIDDEN_VIRTUAL ){
          pNew->aCol[i].iField = -1;
        }else{
          pNew->aCol[i].iField = iField++;
        }
        if( eHidden!=RECOVER_EHIDDEN_VIRTUAL
         && eHidden!=RECOVER_EHIDDEN_STORED
        ){
          pNew->aCol[i].iBind = iBind++;
        }
        memcpy(csr, z, n);
        csr += (n+1);
      }

      pNew->pNext = p->pTblList;
      p->pTblList = pNew;
      pNew->bIntkey = 1;
    }

    recoverFinalize(p, pStmt);

    pStmt = recoverPreparePrintf(p, p->dbOut, "PRAGMA index_xinfo(%Q)", zName);
    while( pStmt && sqlite3_step(pStmt)==SQLITE_ROW ){
      int iField = sqlite3_column_int(pStmt, 0);
      int iCol = sqlite3_column_int(pStmt, 1);

      assert( iField<pNew->nCol && iCol<pNew->nCol );
      pNew->aCol[iCol].iField = iField;

      pNew->bIntkey = 0;
      iPk = -2;
    }
    recoverFinalize(p, pStmt);

    if( p->errCode==SQLITE_OK ){
      if( iPk>=0 ){
        pNew->aCol[iPk].bIPK = 1;
      }else if( pNew->bIntkey ){
        pNew->iRowidBind = iBind++;
      }
    }
  }
}

/*
** This function is called after recoverCacheSchema() has cached those parts
** of the input database schema that could be recovered in temporary table
** "recovery.schema". This function creates in the output database copies
** of all parts of that schema that must be created before the tables can
** be populated. Specifically, this means:
**
**     * all tables that are not VIRTUAL, and
**     * UNIQUE indexes.
**
** If the recovery handle uses SQL callbacks, then callbacks containing
** the associated "CREATE TABLE" and "CREATE INDEX" statements are made.
**
** Additionally, records are added to the sqlite_schema table of the
** output database for any VIRTUAL tables. The CREATE VIRTUAL TABLE
** records are written directly to sqlite_schema, not actually executed.
** If the handle is in SQL callback mode, then callbacks are invoked 
** with equivalent SQL statements.
*/
static int recoverWriteSchema1(sqlite3_recover *p){
  sqlite3_stmt *pSelect = 0;
  sqlite3_stmt *pTblname = 0;

  pSelect = recoverPrepare(p, p->dbOut,
      "WITH dbschema(rootpage, name, sql, tbl, isVirtual, isIndex) AS ("
      "  SELECT rootpage, name, sql, "
      "    type='table', "
      "    sql LIKE 'create virtual%',"
      "    (type='index' AND (sql LIKE '%unique%' OR ?1))"
      "  FROM recovery.schema"
      ")"
      "SELECT rootpage, tbl, isVirtual, name, sql"
      " FROM dbschema "
      "  WHERE tbl OR isIndex"
      "  ORDER BY tbl DESC, name=='sqlite_sequence' DESC"
  );

  pTblname = recoverPrepare(p, p->dbOut,
      "SELECT name FROM sqlite_schema "
      "WHERE type='table' ORDER BY rowid DESC LIMIT 1"
  );

  if( pSelect ){
    sqlite3_bind_int(pSelect, 1, p->bSlowIndexes);
    while( sqlite3_step(pSelect)==SQLITE_ROW ){
      i64 iRoot = sqlite3_column_int64(pSelect, 0);
      int bTable = sqlite3_column_int(pSelect, 1);
      int bVirtual = sqlite3_column_int(pSelect, 2);
      const char *zName = (const char*)sqlite3_column_text(pSelect, 3);
      const char *zSql = (const char*)sqlite3_column_text(pSelect, 4);
      char *zFree = 0;
      int rc = SQLITE_OK;

      if( bVirtual ){
        zSql = (const char*)(zFree = recoverMPrintf(p,
            "INSERT INTO sqlite_schema VALUES('table', %Q, %Q, 0, %Q)",
            zName, zName, zSql
        ));
      }
      rc = sqlite3_exec(p->dbOut, zSql, 0, 0, 0);
      if( rc==SQLITE_OK ){
        recoverSqlCallback(p, zSql);
        if( bTable && !bVirtual ){
          if( SQLITE_ROW==sqlite3_step(pTblname) ){
            const char *zTbl = (const char*)sqlite3_column_text(pTblname, 0);
            recoverAddTable(p, zTbl, iRoot);
          }
          recoverReset(p, pTblname);
        }
      }else if( rc!=SQLITE_ERROR ){
        recoverDbError(p, p->dbOut);
      }
      sqlite3_free(zFree);
    }
  }
  recoverFinalize(p, pSelect);
  recoverFinalize(p, pTblname);

  return p->errCode;
}

/*
** This function is called after the output database has been populated. It
** adds all recovered schema elements that were not created in the output
** database by recoverWriteSchema1() - everything except for tables and
** UNIQUE indexes. Specifically:
**
**     * views,
**     * triggers,
**     * non-UNIQUE indexes.
**
** If the recover handle is in SQL callback mode, then equivalent callbacks
** are issued to create the schema elements.
*/
static int recoverWriteSchema2(sqlite3_recover *p){
  sqlite3_stmt *pSelect = 0;

  pSelect = recoverPrepare(p, p->dbOut,
      p->bSlowIndexes ?
      "SELECT rootpage, sql FROM recovery.schema "
      "  WHERE type!='table' AND type!='index'"
      :
      "SELECT rootpage, sql FROM recovery.schema "
      "  WHERE type!='table' AND (type!='index' OR sql NOT LIKE '%unique%')"
  );

  if( pSelect ){
    while( sqlite3_step(pSelect)==SQLITE_ROW ){
      const char *zSql = (const char*)sqlite3_column_text(pSelect, 1);
      int rc = sqlite3_exec(p->dbOut, zSql, 0, 0, 0);
      if( rc==SQLITE_OK ){
        recoverSqlCallback(p, zSql);
      }else if( rc!=SQLITE_ERROR ){
        recoverDbError(p, p->dbOut);
      }
    }
  }
  recoverFinalize(p, pSelect);

  return p->errCode;
}

/*
** This function is a no-op if recover handle p already contains an error
** (if p->errCode!=SQLITE_OK). In this case it returns NULL.
**
** Otherwise, if the recover handle is configured to create an output
** database (was created by sqlite3_recover_init()), then this function
** prepares and returns an SQL statement to INSERT a new record into table
** pTab, assuming the first nField fields of a record extracted from disk
** are valid.
**
** For example, if table pTab is:
**
**     CREATE TABLE name(a, b GENERATED ALWAYS AS (a+1) STORED, c, d, e);
**
** And nField is 4, then the SQL statement prepared and returned is:
**
**     INSERT INTO (a, c, d) VALUES (?1, ?2, ?3);
**
** In this case even though 4 values were extracted from the input db,
** only 3 are written to the output, as the generated STORED column 
** cannot be written.
**
** If the recover handle is in SQL callback mode, then the SQL statement
** prepared is such that evaluating it returns a single row containing
** a single text value - itself an SQL statement similar to the above,
** except with SQL literals in place of the variables. For example:
**
**     SELECT 'INSERT INTO (a, c, d) VALUES (' 
**          || quote(?1) || ', '
**          || quote(?2) || ', '
**          || quote(?3) || ')';
**
** In either case, it is the responsibility of the caller to eventually
** free the statement handle using sqlite3_finalize().
*/
static sqlite3_stmt *recoverInsertStmt(
  sqlite3_recover *p, 
  RecoverTable *pTab,
  int nField
){
  sqlite3_stmt *pRet = 0;
  const char *zSep = "";
  const char *zSqlSep = "";
  char *zSql = 0;
  char *zFinal = 0;
  char *zBind = 0;
  int ii;
  int bSql = p->xSql ? 1 : 0;

  if( nField<=0 ) return 0;

  assert( nField<=pTab->nCol );

  zSql = recoverMPrintf(p, "INSERT OR IGNORE INTO %Q(", pTab->zTab);

  if( pTab->iRowidBind ){
    assert( pTab->bIntkey );
    zSql = recoverMPrintf(p, "%z_rowid_", zSql);
    if( bSql ){
      zBind = recoverMPrintf(p, "%zquote(?%d)", zBind, pTab->iRowidBind);
    }else{
      zBind = recoverMPrintf(p, "%z?%d", zBind, pTab->iRowidBind);
    }
    zSqlSep = "||', '||";
    zSep = ", ";
  }

  for(ii=0; ii<nField; ii++){
    int eHidden = pTab->aCol[ii].eHidden;
    if( eHidden!=RECOVER_EHIDDEN_VIRTUAL
     && eHidden!=RECOVER_EHIDDEN_STORED
    ){
      assert( pTab->aCol[ii].iField>=0 && pTab->aCol[ii].iBind>=1 );
      zSql = recoverMPrintf(p, "%z%s%Q", zSql, zSep, pTab->aCol[ii].zCol);

      if( bSql ){
        zBind = recoverMPrintf(p, 
            "%z%sescape_crnl(quote(?%d))", zBind, zSqlSep, pTab->aCol[ii].iBind
        );
        zSqlSep = "||', '||";
      }else{
        zBind = recoverMPrintf(p, "%z%s?%d", zBind, zSep, pTab->aCol[ii].iBind);
      }
      zSep = ", ";
    }
  }

  if( bSql ){
    zFinal = recoverMPrintf(p, "SELECT %Q || ') VALUES (' || %s || ')'", 
        zSql, zBind
    );
  }else{
    zFinal = recoverMPrintf(p, "%s) VALUES (%s)", zSql, zBind);
  }

  pRet = recoverPrepare(p, p->dbOut, zFinal);
  sqlite3_free(zSql);
  sqlite3_free(zBind);
  sqlite3_free(zFinal);
  
  return pRet;
}


/*
** Search the list of RecoverTable objects at p->pTblList for one that
** has root page iRoot in the input database. If such an object is found,
** return a pointer to it. Otherwise, return NULL.
*/
static RecoverTable *recoverFindTable(sqlite3_recover *p, u32 iRoot){
  RecoverTable *pRet = 0;
  for(pRet=p->pTblList; pRet && pRet->iRoot!=iRoot; pRet=pRet->pNext);
  return pRet;
}

/*
** This function attempts to create a lost and found table within the 
** output db. If successful, it returns a pointer to a buffer containing
** the name of the new table. It is the responsibility of the caller to
** eventually free this buffer using sqlite3_free().
**
** If an error occurs, NULL is returned and an error code and error 
** message left in the recover handle.
*/
static char *recoverLostAndFoundCreate(
  sqlite3_recover *p,             /* Recover object */
  int nField                      /* Number of column fields in new table */
){
  char *zTbl = 0;
  sqlite3_stmt *pProbe = 0;
  int ii = 0;

  pProbe = recoverPrepare(p, p->dbOut,
    "SELECT 1 FROM sqlite_schema WHERE name=?"
  );
  for(ii=-1; zTbl==0 && p->errCode==SQLITE_OK && ii<1000; ii++){
    int bFail = 0;
    if( ii<0 ){
      zTbl = recoverMPrintf(p, "%s", p->zLostAndFound);
    }else{
      zTbl = recoverMPrintf(p, "%s_%d", p->zLostAndFound, ii);
    }

    if( p->errCode==SQLITE_OK ){
      sqlite3_bind_text(pProbe, 1, zTbl, -1, SQLITE_STATIC);
      if( SQLITE_ROW==sqlite3_step(pProbe) ){
        bFail = 1;
      }
      recoverReset(p, pProbe);
    }

    if( bFail ){
      sqlite3_clear_bindings(pProbe);
      sqlite3_free(zTbl);
      zTbl = 0;
    }
  }
  recoverFinalize(p, pProbe);

  if( zTbl ){
    const char *zSep = 0;
    char *zField = 0;
    char *zSql = 0;

    zSep = "rootpgno INTEGER, pgno INTEGER, nfield INTEGER, id INTEGER, ";
    for(ii=0; p->errCode==SQLITE_OK && ii<nField; ii++){
      zField = recoverMPrintf(p, "%z%sc%d", zField, zSep, ii);
      zSep = ", ";
    }

    zSql = recoverMPrintf(p, "CREATE TABLE %s(%s)", zTbl, zField);
    sqlite3_free(zField);

    recoverExec(p, p->dbOut, zSql);
    recoverSqlCallback(p, zSql);
    sqlite3_free(zSql);
  }else if( p->errCode==SQLITE_OK ){
    recoverError(
        p, SQLITE_ERROR, "failed to create %s output table", p->zLostAndFound
    );
  }

  return zTbl;
}

/*
** Synthesize and prepare an INSERT statement to write to the lost_and_found
** table in the output database. The name of the table is zTab, and it has
** nField c* fields.
*/
static sqlite3_stmt *recoverLostAndFoundInsert(
  sqlite3_recover *p,
  const char *zTab,
  int nField
){
  int nTotal = nField + 4;
  int ii;
  char *zBind = 0;
  sqlite3_stmt *pRet = 0;

  if( p->xSql==0 ){
    for(ii=0; ii<nTotal; ii++){
      zBind = recoverMPrintf(p, "%z%s?", zBind, zBind?", ":"", ii);
    }
    pRet = recoverPreparePrintf(
        p, p->dbOut, "INSERT INTO %s VALUES(%s)", zTab, zBind
    );
  }else{
    const char *zSep = "";
    for(ii=0; ii<nTotal; ii++){
      zBind = recoverMPrintf(p, "%z%squote(?)", zBind, zSep);
      zSep = "|| ', ' ||";
    }
    pRet = recoverPreparePrintf(
        p, p->dbOut, "SELECT 'INSERT INTO %s VALUES(' || %s || ')'", zTab, zBind
    );
  }

  sqlite3_free(zBind);
  return pRet;
}

/*
** Input database page iPg contains data that will be written to the
** lost-and-found table of the output database. This function attempts
** to identify the root page of the tree that page iPg belonged to.
** If successful, it sets output variable (*piRoot) to the page number
** of the root page and returns SQLITE_OK. Otherwise, if an error occurs,
** an SQLite error code is returned and the final value of *piRoot 
** undefined.
*/
static int recoverLostAndFoundFindRoot(
  sqlite3_recover *p, 
  i64 iPg,
  i64 *piRoot
){
  RecoverStateLAF *pLaf = &p->laf;

  if( pLaf->pFindRoot==0 ){
    pLaf->pFindRoot = recoverPrepare(p, p->dbOut,
        "WITH RECURSIVE p(pgno) AS ("
        "  SELECT ?"
        "    UNION"
        "  SELECT parent FROM recovery.map AS m, p WHERE m.pgno=p.pgno"
        ") "
        "SELECT p.pgno FROM p, recovery.map m WHERE m.pgno=p.pgno "
        "    AND m.parent IS NULL"
    );
  }
  if( p->errCode==SQLITE_OK ){
    sqlite3_bind_int64(pLaf->pFindRoot, 1, iPg);
    if( sqlite3_step(pLaf->pFindRoot)==SQLITE_ROW ){
      *piRoot = sqlite3_column_int64(pLaf->pFindRoot, 0);
    }else{
      *piRoot = iPg;
    }
    recoverReset(p, pLaf->pFindRoot);
  }
  return p->errCode;
}

/*
** Recover data from page iPage of the input database and write it to
** the lost-and-found table in the output database.
*/
static void recoverLostAndFoundOnePage(sqlite3_recover *p, i64 iPage){
  RecoverStateLAF *pLaf = &p->laf;
  sqlite3_value **apVal = pLaf->apVal;
  sqlite3_stmt *pPageData = pLaf->pPageData;
  sqlite3_stmt *pInsert = pLaf->pInsert;

  int nVal = -1;
  int iPrevCell = 0;
  i64 iRoot = 0;
  int bHaveRowid = 0;
  i64 iRowid = 0;
  int ii = 0;

  if( recoverLostAndFoundFindRoot(p, iPage, &iRoot) ) return;
  sqlite3_bind_int64(pPageData, 1, iPage);
  while( p->errCode==SQLITE_OK && SQLITE_ROW==sqlite3_step(pPageData) ){
    int iCell = sqlite3_column_int64(pPageData, 0);
    int iField = sqlite3_column_int64(pPageData, 1);

    if( iPrevCell!=iCell && nVal>=0 ){
      /* Insert the new row */
      sqlite3_bind_int64(pInsert, 1, iRoot);      /* rootpgno */
      sqlite3_bind_int64(pInsert, 2, iPage);      /* pgno */
      sqlite3_bind_int(pInsert, 3, nVal);         /* nfield */
      if( bHaveRowid ){
        sqlite3_bind_int64(pInsert, 4, iRowid);   /* id */
      }
      for(ii=0; ii<nVal; ii++){
        recoverBindValue(p, pInsert, 5+ii, apVal[ii]);
      }
      if( sqlite3_step(pInsert)==SQLITE_ROW ){
        recoverSqlCallback(p, (const char*)sqlite3_column_text(pInsert, 0));
      }
      recoverReset(p, pInsert);

      /* Discard the accumulated row data */
      for(ii=0; ii<nVal; ii++){
        sqlite3_value_free(apVal[ii]);
        apVal[ii] = 0;
      }
      sqlite3_clear_bindings(pInsert);
      bHaveRowid = 0;
      nVal = -1;
    }

    if( iCell<0 ) break;

    if( iField<0 ){
      assert( nVal==-1 );
      iRowid = sqlite3_column_int64(pPageData, 2);
      bHaveRowid = 1;
      nVal = 0;
    }else if( iField<pLaf->nMaxField ){
      sqlite3_value *pVal = sqlite3_column_value(pPageData, 2);
      apVal[iField] = sqlite3_value_dup(pVal);
      assert( iField==nVal || (nVal==-1 && iField==0) );
      nVal = iField+1;
      if( apVal[iField]==0 ){
        recoverError(p, SQLITE_NOMEM, 0);
      }
    }

    iPrevCell = iCell;
  }
  recoverReset(p, pPageData);

  for(ii=0; ii<nVal; ii++){
    sqlite3_value_free(apVal[ii]);
    apVal[ii] = 0;
  }
}

/*
** Perform one step (sqlite3_recover_step()) of work for the connection 
** passed as the only argument, which is guaranteed to be in
** RECOVER_STATE_LOSTANDFOUND3 state - during which the lost-and-found 
** table of the output database is populated with recovered data that can 
** not be assigned to any recovered schema object.
*/ 
static int recoverLostAndFound3Step(sqlite3_recover *p){
  RecoverStateLAF *pLaf = &p->laf;
  if( p->errCode==SQLITE_OK ){
    if( pLaf->pInsert==0 ){
      return SQLITE_DONE;
    }else{
      if( p->errCode==SQLITE_OK ){
        int res = sqlite3_step(pLaf->pAllPage);
        if( res==SQLITE_ROW ){
          i64 iPage = sqlite3_column_int64(pLaf->pAllPage, 0);
          if( recoverBitmapQuery(pLaf->pUsed, iPage)==0 ){
            recoverLostAndFoundOnePage(p, iPage);
          }
        }else{
          recoverReset(p, pLaf->pAllPage);
          return SQLITE_DONE;
        }
      }
    }
  }
  return SQLITE_OK;
}

/*
** Initialize resources required in RECOVER_STATE_LOSTANDFOUND3 
** state - during which the lost-and-found table of the output database 
** is populated with recovered data that can not be assigned to any 
** recovered schema object.
*/ 
static void recoverLostAndFound3Init(sqlite3_recover *p){
  RecoverStateLAF *pLaf = &p->laf;

  if( pLaf->nMaxField>0 ){
    char *zTab = 0;               /* Name of lost_and_found table */

    zTab = recoverLostAndFoundCreate(p, pLaf->nMaxField);
    pLaf->pInsert = recoverLostAndFoundInsert(p, zTab, pLaf->nMaxField);
    sqlite3_free(zTab);

    pLaf->pAllPage = recoverPreparePrintf(p, p->dbOut,
        "WITH RECURSIVE seq(ii) AS ("
        "  SELECT 1 UNION ALL SELECT ii+1 FROM seq WHERE ii<%lld"
        ")"
        "SELECT ii FROM seq" , p->laf.nPg
    );
    pLaf->pPageData = recoverPrepare(p, p->dbOut,
        "SELECT cell, field, value "
        "FROM sqlite_dbdata('getpage()') d WHERE d.pgno=? "
        "UNION ALL "
        "SELECT -1, -1, -1"
    );

    pLaf->apVal = (sqlite3_value**)recoverMalloc(p, 
        pLaf->nMaxField*sizeof(sqlite3_value*)
    );
  }
}

/*
** Initialize resources required in RECOVER_STATE_WRITING state - during which
** tables recovered from the schema of the input database are populated with
** recovered data.
*/ 
static int recoverWriteDataInit(sqlite3_recover *p){
  RecoverStateW1 *p1 = &p->w1;
  RecoverTable *pTbl = 0;
  int nByte = 0;

  /* Figure out the maximum number of columns for any table in the schema */
  assert( p1->nMax==0 );
  for(pTbl=p->pTblList; pTbl; pTbl=pTbl->pNext){
    if( pTbl->nCol>p1->nMax ) p1->nMax = pTbl->nCol;
  }

  /* Allocate an array of (sqlite3_value*) in which to accumulate the values
  ** that will be written to the output database in a single row. */
  nByte = sizeof(sqlite3_value*) * (p1->nMax+1);
  p1->apVal = (sqlite3_value**)recoverMalloc(p, nByte);
  if( p1->apVal==0 ) return p->errCode;

  /* Prepare the SELECT to loop through schema tables (pTbls) and the SELECT
  ** to loop through cells that appear to belong to a single table (pSel). */
  p1->pTbls = recoverPrepare(p, p->dbOut,
      "SELECT rootpage FROM recovery.schema "
      "  WHERE type='table' AND (sql NOT LIKE 'create virtual%')"
      "  ORDER BY (tbl_name='sqlite_sequence') ASC"
  );
  p1->pSel = recoverPrepare(p, p->dbOut, 
      "WITH RECURSIVE pages(page) AS ("
      "  SELECT ?1"
      "    UNION"
      "  SELECT child FROM sqlite_dbptr('getpage()'), pages "
      "    WHERE pgno=page"
      ") "
      "SELECT page, cell, field, value "
      "FROM sqlite_dbdata('getpage()') d, pages p WHERE p.page=d.pgno "
      "UNION ALL "
      "SELECT 0, 0, 0, 0"
  );

  return p->errCode;
}

/*
** Clean up resources allocated by recoverWriteDataInit() (stuff in 
** sqlite3_recover.w1).
*/
static void recoverWriteDataCleanup(sqlite3_recover *p){
  RecoverStateW1 *p1 = &p->w1;
  int ii;
  for(ii=0; ii<p1->nVal; ii++){
    sqlite3_value_free(p1->apVal[ii]);
  }
  sqlite3_free(p1->apVal);
  recoverFinalize(p, p1->pInsert);
  recoverFinalize(p, p1->pTbls);
  recoverFinalize(p, p1->pSel);
  memset(p1, 0, sizeof(*p1));
}

/*
** Perform one step (sqlite3_recover_step()) of work for the connection 
** passed as the only argument, which is guaranteed to be in
** RECOVER_STATE_WRITING state - during which tables recovered from the
** schema of the input database are populated with recovered data.
*/ 
static int recoverWriteDataStep(sqlite3_recover *p){
  RecoverStateW1 *p1 = &p->w1;
  sqlite3_stmt *pSel = p1->pSel;
  sqlite3_value **apVal = p1->apVal;

  if( p->errCode==SQLITE_OK && p1->pTab==0 ){
    if( sqlite3_step(p1->pTbls)==SQLITE_ROW ){
      i64 iRoot = sqlite3_column_int64(p1->pTbls, 0);
      p1->pTab = recoverFindTable(p, iRoot);

      recoverFinalize(p, p1->pInsert);
      p1->pInsert = 0;

      /* If this table is unknown, return early. The caller will invoke this
      ** function again and it will move on to the next table.  */
      if( p1->pTab==0 ) return p->errCode;

      /* If this is the sqlite_sequence table, delete any rows added by
      ** earlier INSERT statements on tables with AUTOINCREMENT primary
      ** keys before recovering its contents. The p1->pTbls SELECT statement
      ** is rigged to deliver "sqlite_sequence" last of all, so we don't
      ** worry about it being modified after it is recovered. */
      if( sqlite3_stricmp("sqlite_sequence", p1->pTab->zTab)==0 ){
        recoverExec(p, p->dbOut, "DELETE FROM sqlite_sequence");
        recoverSqlCallback(p, "DELETE FROM sqlite_sequence");
      }

      /* Bind the root page of this table within the original database to 
      ** SELECT statement p1->pSel. The SELECT statement will then iterate
      ** through cells that look like they belong to table pTab.  */
      sqlite3_bind_int64(pSel, 1, iRoot);

      p1->nVal = 0;
      p1->bHaveRowid = 0;
      p1->iPrevPage = -1;
      p1->iPrevCell = -1;
    }else{
      return SQLITE_DONE;
    }
  }
  assert( p->errCode!=SQLITE_OK || p1->pTab );

  if( p->errCode==SQLITE_OK && sqlite3_step(pSel)==SQLITE_ROW ){
    RecoverTable *pTab = p1->pTab;

    i64 iPage = sqlite3_column_int64(pSel, 0);
    int iCell = sqlite3_column_int(pSel, 1);
    int iField = sqlite3_column_int(pSel, 2);
    sqlite3_value *pVal = sqlite3_column_value(pSel, 3);
    int bNewCell = (p1->iPrevPage!=iPage || p1->iPrevCell!=iCell);

    assert( bNewCell==0 || (iField==-1 || iField==0) );
    assert( bNewCell || iField==p1->nVal || p1->nVal==pTab->nCol );

    if( bNewCell ){
      int ii = 0;
      if( p1->nVal>=0 ){
        if( p1->pInsert==0 || p1->nVal!=p1->nInsert ){
          recoverFinalize(p, p1->pInsert);
          p1->pInsert = recoverInsertStmt(p, pTab, p1->nVal);
          p1->nInsert = p1->nVal;
        }
        if( p1->nVal>0 ){
          sqlite3_stmt *pInsert = p1->pInsert;
          for(ii=0; ii<pTab->nCol; ii++){
            RecoverColumn *pCol = &pTab->aCol[ii];
            int iBind = pCol->iBind;
            if( iBind>0 ){
              if( pCol->bIPK ){
                sqlite3_bind_int64(pInsert, iBind, p1->iRowid);
              }else if( pCol->iField<p1->nVal ){
                recoverBindValue(p, pInsert, iBind, apVal[pCol->iField]);
              }
            }
          }
          if( p->bRecoverRowid && pTab->iRowidBind>0 && p1->bHaveRowid ){
            sqlite3_bind_int64(pInsert, pTab->iRowidBind, p1->iRowid);
          }
          if( SQLITE_ROW==sqlite3_step(pInsert) ){
            const char *z = (const char*)sqlite3_column_text(pInsert, 0);
            recoverSqlCallback(p, z);
          }
          recoverReset(p, pInsert);
          assert( p->errCode || pInsert );
          if( pInsert ) sqlite3_clear_bindings(pInsert);
        }
      }

      for(ii=0; ii<p1->nVal; ii++){
        sqlite3_value_free(apVal[ii]);
        apVal[ii] = 0;
      }
      p1->nVal = -1;
      p1->bHaveRowid = 0;
    }

    if( iPage!=0 ){
      if( iField<0 ){
        p1->iRowid = sqlite3_column_int64(pSel, 3);
        assert( p1->nVal==-1 );
        p1->nVal = 0;
        p1->bHaveRowid = 1;
      }else if( iField<pTab->nCol ){
        assert( apVal[iField]==0 );
        apVal[iField] = sqlite3_value_dup( pVal );
        if( apVal[iField]==0 ){
          recoverError(p, SQLITE_NOMEM, 0);
        }
        p1->nVal = iField+1;
      }
      p1->iPrevCell = iCell;
      p1->iPrevPage = iPage;
    }
  }else{
    recoverReset(p, pSel);
    p1->pTab = 0;
  }

  return p->errCode;
}

/*
** Initialize resources required by sqlite3_recover_step() in
** RECOVER_STATE_LOSTANDFOUND1 state - during which the set of pages not
** already allocated to a recovered schema element is determined.
*/ 
static void recoverLostAndFound1Init(sqlite3_recover *p){
  RecoverStateLAF *pLaf = &p->laf;
  sqlite3_stmt *pStmt = 0;

  assert( p->laf.pUsed==0 );
  pLaf->nPg = recoverPageCount(p);
  pLaf->pUsed = recoverBitmapAlloc(p, pLaf->nPg);

  /* Prepare a statement to iterate through all pages that are part of any tree
  ** in the recoverable part of the input database schema to the bitmap. And,
  ** if !p->bFreelistCorrupt, add all pages that appear to be part of the
  ** freelist.  */
  pStmt = recoverPrepare(
      p, p->dbOut,
      "WITH trunk(pgno) AS ("
      "  SELECT read_i32(getpage(1), 8) AS x WHERE x>0"
      "    UNION"
      "  SELECT read_i32(getpage(trunk.pgno), 0) AS x FROM trunk WHERE x>0"
      "),"
      "trunkdata(pgno, data) AS ("
      "  SELECT pgno, getpage(pgno) FROM trunk"
      "),"
      "freelist(data, n, freepgno) AS ("
      "  SELECT data, min(16384, read_i32(data, 1)-1), pgno FROM trunkdata"
      "    UNION ALL"
      "  SELECT data, n-1, read_i32(data, 2+n) FROM freelist WHERE n>=0"
      "),"
      ""
      "roots(r) AS ("
      "  SELECT 1 UNION ALL"
      "  SELECT rootpage FROM recovery.schema WHERE rootpage>0"
      "),"
      "used(page) AS ("
      "  SELECT r FROM roots"
      "    UNION"
      "  SELECT child FROM sqlite_dbptr('getpage()'), used "
      "    WHERE pgno=page"
      ") "
      "SELECT page FROM used"
      " UNION ALL "
      "SELECT freepgno FROM freelist WHERE NOT ?"
  );
  if( pStmt ) sqlite3_bind_int(pStmt, 1, p->bFreelistCorrupt);
  pLaf->pUsedPages = pStmt;
}

/*
** Perform one step (sqlite3_recover_step()) of work for the connection 
** passed as the only argument, which is guaranteed to be in
** RECOVER_STATE_LOSTANDFOUND1 state - during which the set of pages not
** already allocated to a recovered schema element is determined.
*/ 
static int recoverLostAndFound1Step(sqlite3_recover *p){
  RecoverStateLAF *pLaf = &p->laf;
  int rc = p->errCode;
  if( rc==SQLITE_OK ){
    rc = sqlite3_step(pLaf->pUsedPages);
    if( rc==SQLITE_ROW ){
      i64 iPg = sqlite3_column_int64(pLaf->pUsedPages, 0);
      recoverBitmapSet(pLaf->pUsed, iPg);
      rc = SQLITE_OK;
    }else{
      recoverFinalize(p, pLaf->pUsedPages);
      pLaf->pUsedPages = 0;
    }
  }
  return rc;
}

/*
** Initialize resources required by RECOVER_STATE_LOSTANDFOUND2 
** state - during which the pages identified in RECOVER_STATE_LOSTANDFOUND1
** are sorted into sets that likely belonged to the same database tree.
*/ 
static void recoverLostAndFound2Init(sqlite3_recover *p){
  RecoverStateLAF *pLaf = &p->laf;

  assert( p->laf.pAllAndParent==0 );
  assert( p->laf.pMapInsert==0 );
  assert( p->laf.pMaxField==0 );
  assert( p->laf.nMaxField==0 );

  pLaf->pMapInsert = recoverPrepare(p, p->dbOut,
      "INSERT OR IGNORE INTO recovery.map(pgno, parent) VALUES(?, ?)"
  );
  pLaf->pAllAndParent = recoverPreparePrintf(p, p->dbOut,
      "WITH RECURSIVE seq(ii) AS ("
      "  SELECT 1 UNION ALL SELECT ii+1 FROM seq WHERE ii<%lld"
      ")"
      "SELECT pgno, child FROM sqlite_dbptr('getpage()') "
      " UNION ALL "
      "SELECT NULL, ii FROM seq", p->laf.nPg
  );
  pLaf->pMaxField = recoverPreparePrintf(p, p->dbOut,
      "SELECT max(field)+1 FROM sqlite_dbdata('getpage') WHERE pgno = ?"
  );
}

/*
** Perform one step (sqlite3_recover_step()) of work for the connection 
** passed as the only argument, which is guaranteed to be in
** RECOVER_STATE_LOSTANDFOUND2 state - during which the pages identified 
** in RECOVER_STATE_LOSTANDFOUND1 are sorted into sets that likely belonged 
** to the same database tree.
*/ 
static int recoverLostAndFound2Step(sqlite3_recover *p){
  RecoverStateLAF *pLaf = &p->laf;
  if( p->errCode==SQLITE_OK ){
    int res = sqlite3_step(pLaf->pAllAndParent);
    if( res==SQLITE_ROW ){
      i64 iChild = sqlite3_column_int(pLaf->pAllAndParent, 1);
      if( recoverBitmapQuery(pLaf->pUsed, iChild)==0 ){
        sqlite3_bind_int64(pLaf->pMapInsert, 1, iChild);
        sqlite3_bind_value(pLaf->pMapInsert, 2, 
            sqlite3_column_value(pLaf->pAllAndParent, 0)
        );
        sqlite3_step(pLaf->pMapInsert);
        recoverReset(p, pLaf->pMapInsert);
        sqlite3_bind_int64(pLaf->pMaxField, 1, iChild);
        if( SQLITE_ROW==sqlite3_step(pLaf->pMaxField) ){
          int nMax = sqlite3_column_int(pLaf->pMaxField, 0);
          if( nMax>pLaf->nMaxField ) pLaf->nMaxField = nMax;
        }
        recoverReset(p, pLaf->pMaxField);
      }
    }else{
      recoverFinalize(p, pLaf->pAllAndParent);
      pLaf->pAllAndParent =0;
      return SQLITE_DONE;
    }
  }
  return p->errCode;
}

/*
** Free all resources allocated as part of sqlite3_recover_step() calls
** in one of the RECOVER_STATE_LOSTANDFOUND[123] states.
*/
static void recoverLostAndFoundCleanup(sqlite3_recover *p){
  recoverBitmapFree(p->laf.pUsed);
  p->laf.pUsed = 0;
  sqlite3_finalize(p->laf.pUsedPages);
  sqlite3_finalize(p->laf.pAllAndParent);
  sqlite3_finalize(p->laf.pMapInsert);
  sqlite3_finalize(p->laf.pMaxField);
  sqlite3_finalize(p->laf.pFindRoot);
  sqlite3_finalize(p->laf.pInsert);
  sqlite3_finalize(p->laf.pAllPage);
  sqlite3_finalize(p->laf.pPageData);
  p->laf.pUsedPages = 0;
  p->laf.pAllAndParent = 0;
  p->laf.pMapInsert = 0;
  p->laf.pMaxField = 0;
  p->laf.pFindRoot = 0;
  p->laf.pInsert = 0;
  p->laf.pAllPage = 0;
  p->laf.pPageData = 0;
  sqlite3_free(p->laf.apVal);
  p->laf.apVal = 0;
}

/*
** Free all resources allocated as part of sqlite3_recover_step() calls.
*/
static void recoverFinalCleanup(sqlite3_recover *p){
  RecoverTable *pTab = 0;
  RecoverTable *pNext = 0;

  recoverWriteDataCleanup(p);
  recoverLostAndFoundCleanup(p);

  for(pTab=p->pTblList; pTab; pTab=pNext){
    pNext = pTab->pNext;
    sqlite3_free(pTab);
  }
  p->pTblList = 0;
  sqlite3_finalize(p->pGetPage);
  p->pGetPage = 0;

  {
#ifndef NDEBUG
    int res = 
#endif
       sqlite3_close(p->dbOut);
    assert( res==SQLITE_OK );
  }
  p->dbOut = 0;
}

/*
** Decode and return an unsigned 16-bit big-endian integer value from 
** buffer a[].
*/
static u32 recoverGetU16(const u8 *a){
  return (((u32)a[0])<<8) + ((u32)a[1]);
}

/*
** Decode and return an unsigned 32-bit big-endian integer value from 
** buffer a[].
*/
static u32 recoverGetU32(const u8 *a){
  return (((u32)a[0])<<24) + (((u32)a[1])<<16) + (((u32)a[2])<<8) + ((u32)a[3]);
}

/*
** Decode an SQLite varint from buffer a[]. Write the decoded value to (*pVal)
** and return the number of bytes consumed.
*/
static int recoverGetVarint(const u8 *a, i64 *pVal){
  sqlite3_uint64 u = 0;
  int i;
  for(i=0; i<8; i++){
    u = (u<<7) + (a[i]&0x7f);
    if( (a[i]&0x80)==0 ){ *pVal = (sqlite3_int64)u; return i+1; }
  }
  u = (u<<8) + (a[i]&0xff);
  *pVal = (sqlite3_int64)u;
  return 9;
}

/*
** The second argument points to a buffer n bytes in size. If this buffer
** or a prefix thereof appears to contain a well-formed SQLite b-tree page, 
** return the page-size in bytes. Otherwise, if the buffer does not 
** appear to contain a well-formed b-tree page, return 0.
*/
static int recoverIsValidPage(u8 *aTmp, const u8 *a, int n){
  u8 *aUsed = aTmp;
  int nFrag = 0;
  int nActual = 0;
  int iFree = 0;
  int nCell = 0;                  /* Number of cells on page */
  int iCellOff = 0;               /* Offset of cell array in page */
  int iContent = 0;
  int eType = 0;
  int ii = 0;

  eType = (int)a[0];
  if( eType!=0x02 && eType!=0x05 && eType!=0x0A && eType!=0x0D ) return 0;

  iFree = (int)recoverGetU16(&a[1]);
  nCell = (int)recoverGetU16(&a[3]);
  iContent = (int)recoverGetU16(&a[5]);
  if( iContent==0 ) iContent = 65536;
  nFrag = (int)a[7];

  if( iContent>n ) return 0;

  memset(aUsed, 0, n);
  memset(aUsed, 0xFF, iContent);

  /* Follow the free-list. This is the same format for all b-tree pages. */
  if( iFree && iFree<=iContent ) return 0;
  while( iFree ){
    int iNext = 0;
    int nByte = 0;
    if( iFree>(n-4) ) return 0;
    iNext = recoverGetU16(&a[iFree]);
    nByte = recoverGetU16(&a[iFree+2]);
    if( iFree+nByte>n ) return 0;
    if( iNext && iNext<iFree+nByte ) return 0;
    memset(&aUsed[iFree], 0xFF, nByte);
    iFree = iNext;
  }

  /* Run through the cells */
  if( eType==0x02 || eType==0x05 ){
    iCellOff = 12;
  }else{
    iCellOff = 8;
  }
  if( (iCellOff + 2*nCell)>iContent ) return 0;
  for(ii=0; ii<nCell; ii++){
    int iByte;
    i64 nPayload = 0;
    int nByte = 0;
    int iOff = recoverGetU16(&a[iCellOff + 2*ii]);
    if( iOff<iContent || iOff>n ){
      return 0;
    }
    if( eType==0x05 || eType==0x02 ) nByte += 4;
    nByte += recoverGetVarint(&a[iOff+nByte], &nPayload);
    if( eType==0x0D ){
      i64 dummy = 0;
      nByte += recoverGetVarint(&a[iOff+nByte], &dummy);
    }
    if( eType!=0x05 ){
      int X = (eType==0x0D) ? n-35 : (((n-12)*64/255)-23);
      int M = ((n-12)*32/255)-23;
      int K = M+((nPayload-M)%(n-4));

      if( nPayload<X ){
        nByte += nPayload;
      }else if( K<=X ){
        nByte += K+4;
      }else{
        nByte += M+4;
      }
    }

    if( iOff+nByte>n ){
      return 0;
    }
    for(iByte=iOff; iByte<(iOff+nByte); iByte++){
      if( aUsed[iByte]!=0 ){
        return 0;
      }
      aUsed[iByte] = 0xFF;
    }
  }

  nActual = 0;
  for(ii=0; ii<n; ii++){
    if( aUsed[ii]==0 ) nActual++;
  }
  return (nActual==nFrag);
}


static int recoverVfsClose(sqlite3_file*);
static int recoverVfsRead(sqlite3_file*, void*, int iAmt, sqlite3_int64 iOfst);
static int recoverVfsWrite(sqlite3_file*, const void*, int, sqlite3_int64);
static int recoverVfsTruncate(sqlite3_file*, sqlite3_int64 size);
static int recoverVfsSync(sqlite3_file*, int flags);
static int recoverVfsFileSize(sqlite3_file*, sqlite3_int64 *pSize);
static int recoverVfsLock(sqlite3_file*, int);
static int recoverVfsUnlock(sqlite3_file*, int);
static int recoverVfsCheckReservedLock(sqlite3_file*, int *pResOut);
static int recoverVfsFileControl(sqlite3_file*, int op, void *pArg);
static int recoverVfsSectorSize(sqlite3_file*);
static int recoverVfsDeviceCharacteristics(sqlite3_file*);
static int recoverVfsShmMap(sqlite3_file*, int, int, int, void volatile**);
static int recoverVfsShmLock(sqlite3_file*, int offset, int n, int flags);
static void recoverVfsShmBarrier(sqlite3_file*);
static int recoverVfsShmUnmap(sqlite3_file*, int deleteFlag);
static int recoverVfsFetch(sqlite3_file*, sqlite3_int64, int, void**);
static int recoverVfsUnfetch(sqlite3_file *pFd, sqlite3_int64 iOff, void *p);

static sqlite3_io_methods recover_methods = {
  2, /* iVersion */
  recoverVfsClose,
  recoverVfsRead,
  recoverVfsWrite,
  recoverVfsTruncate,
  recoverVfsSync,
  recoverVfsFileSize,
  recoverVfsLock,
  recoverVfsUnlock,
  recoverVfsCheckReservedLock,
  recoverVfsFileControl,
  recoverVfsSectorSize,
  recoverVfsDeviceCharacteristics,
  recoverVfsShmMap,
  recoverVfsShmLock,
  recoverVfsShmBarrier,
  recoverVfsShmUnmap,
  recoverVfsFetch,
  recoverVfsUnfetch
};

static int recoverVfsClose(sqlite3_file *pFd){
  assert( pFd->pMethods!=&recover_methods );
  return pFd->pMethods->xClose(pFd);
}

/*
** Write value v to buffer a[] as a 16-bit big-endian unsigned integer.
*/
static void recoverPutU16(u8 *a, u32 v){
  a[0] = (v>>8) & 0x00FF;
  a[1] = (v>>0) & 0x00FF;
}

/*
** Write value v to buffer a[] as a 32-bit big-endian unsigned integer.
*/
static void recoverPutU32(u8 *a, u32 v){
  a[0] = (v>>24) & 0x00FF;
  a[1] = (v>>16) & 0x00FF;
  a[2] = (v>>8) & 0x00FF;
  a[3] = (v>>0) & 0x00FF;
}

/*
** Detect the page-size of the database opened by file-handle pFd by 
** searching the first part of the file for a well-formed SQLite b-tree 
** page. If parameter nReserve is non-zero, then as well as searching for
** a b-tree page with zero reserved bytes, this function searches for one
** with nReserve reserved bytes at the end of it.
**
** If successful, set variable p->detected_pgsz to the detected page-size
** in bytes and return SQLITE_OK. Or, if no error occurs but no valid page
** can be found, return SQLITE_OK but leave p->detected_pgsz set to 0. Or,
** if an error occurs (e.g. an IO or OOM error), then an SQLite error code
** is returned. The final value of p->detected_pgsz is undefined in this
** case.
*/
static int recoverVfsDetectPagesize(
  sqlite3_recover *p,             /* Recover handle */
  sqlite3_file *pFd,              /* File-handle open on input database */
  u32 nReserve,                   /* Possible nReserve value */
  i64 nSz                         /* Size of database file in bytes */
){
  int rc = SQLITE_OK;
  const int nMin = 512;
  const int nMax = 65536;
  const int nMaxBlk = 4;
  u32 pgsz = 0;
  int iBlk = 0;
  u8 *aPg = 0;
  u8 *aTmp = 0;
  int nBlk = 0;

  aPg = (u8*)sqlite3_malloc(2*nMax);
  if( aPg==0 ) return SQLITE_NOMEM;
  aTmp = &aPg[nMax];

  nBlk = (nSz+nMax-1)/nMax;
  if( nBlk>nMaxBlk ) nBlk = nMaxBlk;

  do {
    for(iBlk=0; rc==SQLITE_OK && iBlk<nBlk; iBlk++){
      int nByte = (nSz>=((iBlk+1)*nMax)) ? nMax : (nSz % nMax);
      memset(aPg, 0, nMax);
      rc = pFd->pMethods->xRead(pFd, aPg, nByte, iBlk*nMax);
      if( rc==SQLITE_OK ){
        int pgsz2;
        for(pgsz2=(pgsz ? pgsz*2 : nMin); pgsz2<=nMax; pgsz2=pgsz2*2){
          int iOff;
          for(iOff=0; iOff<nMax; iOff+=pgsz2){
            if( recoverIsValidPage(aTmp, &aPg[iOff], pgsz2-nReserve) ){
              pgsz = pgsz2;
              break;
            }
          }
        }
      }
    }
    if( pgsz>(u32)p->detected_pgsz ){
      p->detected_pgsz = pgsz;
      p->nReserve = nReserve;
    }
    if( nReserve==0 ) break;
    nReserve = 0;
  }while( 1 );

  p->detected_pgsz = pgsz;
  sqlite3_free(aPg);
  return rc;
}

/*
** The xRead() method of the wrapper VFS. This is used to intercept calls
** to read page 1 of the input database.
*/
static int recoverVfsRead(sqlite3_file *pFd, void *aBuf, int nByte, i64 iOff){
  int rc = SQLITE_OK;
  if( pFd->pMethods==&recover_methods ){
    pFd->pMethods = recover_g.pMethods;
    rc = pFd->pMethods->xRead(pFd, aBuf, nByte, iOff);
    if( nByte==16 ){
      sqlite3_randomness(16, aBuf);
    }else
    if( rc==SQLITE_OK && iOff==0 && nByte>=108 ){
      /* Ensure that the database has a valid header file. The only fields
      ** that really matter to recovery are:
      **
      **   + Database page size (16-bits at offset 16)
      **   + Size of db in pages (32-bits at offset 28)
      **   + Database encoding (32-bits at offset 56)
      **
      ** Also preserved are:
      **
      **   + first freelist page (32-bits at offset 32)
      **   + size of freelist (32-bits at offset 36)
      **
      ** We also try to preserve the auto-vacuum, incr-value, user-version
      ** and application-id fields - all 32 bit quantities at offsets 
      ** 52, 60, 64 and 68. All other fields are set to known good values.
      **
      ** Byte offset 105 should also contain the page-size as a 16-bit 
      ** integer.
      */
      const int aPreserve[] = {32, 36, 52, 60, 64, 68};
      u8 aHdr[108] = {
        0x53, 0x51, 0x4c, 0x69, 0x74, 0x65, 0x20, 0x66, 
        0x6f, 0x72, 0x6d, 0x61, 0x74, 0x20, 0x33, 0x00,
        0xFF, 0xFF, 0x01, 0x01, 0x00, 0x40, 0x20, 0x20,
        0x00, 0x00, 0x00, 0x00, 0xFF, 0xFF, 0xFF, 0xFF,
        0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x04,
        0x00, 0x00, 0x10, 0x00, 0xFF, 0xFF, 0xFF, 0xFF,
        0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
        0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x2e, 0x5b, 0x30,

        0x0D, 0x00, 0x00, 0x00, 0x00, 0xFF, 0xFF, 0x00
      };
      u8 *a = (u8*)aBuf;

      u32 pgsz = recoverGetU16(&a[16]);
      u32 nReserve = a[20];
      u32 enc = recoverGetU32(&a[56]);
      u32 dbsz = 0;
      i64 dbFileSize = 0;
      int ii;
      sqlite3_recover *p = recover_g.p;

      if( pgsz==0x01 ) pgsz = 65536;
      rc = pFd->pMethods->xFileSize(pFd, &dbFileSize);

      if( rc==SQLITE_OK && p->detected_pgsz==0 ){
        rc = recoverVfsDetectPagesize(p, pFd, nReserve, dbFileSize);
      }
      if( p->detected_pgsz ){
        pgsz = p->detected_pgsz;
        nReserve = p->nReserve;
      }

      if( pgsz ){
        dbsz = dbFileSize / pgsz;
      }
      if( enc!=SQLITE_UTF8 && enc!=SQLITE_UTF16BE && enc!=SQLITE_UTF16LE ){
        enc = SQLITE_UTF8;
      }

      sqlite3_free(p->pPage1Cache);
      p->pPage1Cache = 0;
      p->pPage1Disk = 0;

      p->pgsz = nByte;
      p->pPage1Cache = (u8*)recoverMalloc(p, nByte*2);
      if( p->pPage1Cache ){
        p->pPage1Disk = &p->pPage1Cache[nByte];
        memcpy(p->pPage1Disk, aBuf, nByte);

        recoverPutU32(&aHdr[28], dbsz);
        recoverPutU32(&aHdr[56], enc);
        recoverPutU16(&aHdr[105], pgsz-nReserve);
        if( pgsz==65536 ) pgsz = 1;
        recoverPutU16(&aHdr[16], pgsz);
        aHdr[20] = nReserve;
        for(ii=0; ii<sizeof(aPreserve)/sizeof(aPreserve[0]); ii++){
          memcpy(&aHdr[aPreserve[ii]], &a[aPreserve[ii]], 4);
        }
        memcpy(aBuf, aHdr, sizeof(aHdr));
        memset(&((u8*)aBuf)[sizeof(aHdr)], 0, nByte-sizeof(aHdr));

        memcpy(p->pPage1Cache, aBuf, nByte);
      }else{
        rc = p->errCode;
      }

    }
    pFd->pMethods = &recover_methods;
  }else{
    rc = pFd->pMethods->xRead(pFd, aBuf, nByte, iOff);
  }
  return rc;
}

/*
** Used to make sqlite3_io_methods wrapper methods less verbose.
*/
#define RECOVER_VFS_WRAPPER(code)                         \
  int rc = SQLITE_OK;                                     \
  if( pFd->pMethods==&recover_methods ){                  \
    pFd->pMethods = recover_g.pMethods;                   \
    rc = code;                                            \
    pFd->pMethods = &recover_methods;                     \
  }else{                                                  \
    rc = code;                                            \
  }                                                       \
  return rc;                                              

/*
** Methods of the wrapper VFS. All methods except for xRead() and xClose()
** simply uninstall the sqlite3_io_methods wrapper, invoke the equivalent
** method on the lower level VFS, then reinstall the wrapper before returning.
** Those that return an integer value use the RECOVER_VFS_WRAPPER macro.
*/
static int recoverVfsWrite(
  sqlite3_file *pFd, const void *aBuf, int nByte, i64 iOff
){
  RECOVER_VFS_WRAPPER (
      pFd->pMethods->xWrite(pFd, aBuf, nByte, iOff)
  );
}
static int recoverVfsTruncate(sqlite3_file *pFd, sqlite3_int64 size){
  RECOVER_VFS_WRAPPER (
      pFd->pMethods->xTruncate(pFd, size)
  );
}
static int recoverVfsSync(sqlite3_file *pFd, int flags){
  RECOVER_VFS_WRAPPER (
      pFd->pMethods->xSync(pFd, flags)
  );
}
static int recoverVfsFileSize(sqlite3_file *pFd, sqlite3_int64 *pSize){
  RECOVER_VFS_WRAPPER (
      pFd->pMethods->xFileSize(pFd, pSize)
  );
}
static int recoverVfsLock(sqlite3_file *pFd, int eLock){
  RECOVER_VFS_WRAPPER (
      pFd->pMethods->xLock(pFd, eLock)
  );
}
static int recoverVfsUnlock(sqlite3_file *pFd, int eLock){
  RECOVER_VFS_WRAPPER (
      pFd->pMethods->xUnlock(pFd, eLock)
  );
}
static int recoverVfsCheckReservedLock(sqlite3_file *pFd, int *pResOut){
  RECOVER_VFS_WRAPPER (
      pFd->pMethods->xCheckReservedLock(pFd, pResOut)
  );
}
static int recoverVfsFileControl(sqlite3_file *pFd, int op, void *pArg){
  RECOVER_VFS_WRAPPER (
    (pFd->pMethods ?  pFd->pMethods->xFileControl(pFd, op, pArg) : SQLITE_NOTFOUND)
  );
}
static int recoverVfsSectorSize(sqlite3_file *pFd){
  RECOVER_VFS_WRAPPER (
      pFd->pMethods->xSectorSize(pFd)
  );
}
static int recoverVfsDeviceCharacteristics(sqlite3_file *pFd){
  RECOVER_VFS_WRAPPER (
      pFd->pMethods->xDeviceCharacteristics(pFd)
  );
}
static int recoverVfsShmMap(
  sqlite3_file *pFd, int iPg, int pgsz, int bExtend, void volatile **pp
){
  RECOVER_VFS_WRAPPER (
      pFd->pMethods->xShmMap(pFd, iPg, pgsz, bExtend, pp)
  );
}
static int recoverVfsShmLock(sqlite3_file *pFd, int offset, int n, int flags){
  RECOVER_VFS_WRAPPER (
      pFd->pMethods->xShmLock(pFd, offset, n, flags)
  );
}
static void recoverVfsShmBarrier(sqlite3_file *pFd){
  if( pFd->pMethods==&recover_methods ){
    pFd->pMethods = recover_g.pMethods;
    pFd->pMethods->xShmBarrier(pFd);
    pFd->pMethods = &recover_methods;
  }else{
    pFd->pMethods->xShmBarrier(pFd);
  }
}
static int recoverVfsShmUnmap(sqlite3_file *pFd, int deleteFlag){
  RECOVER_VFS_WRAPPER (
      pFd->pMethods->xShmUnmap(pFd, deleteFlag)
  );
}

static int recoverVfsFetch(
  sqlite3_file *pFd, 
  sqlite3_int64 iOff, 
  int iAmt, 
  void **pp
){
  *pp = 0;
  return SQLITE_OK;
}
static int recoverVfsUnfetch(sqlite3_file *pFd, sqlite3_int64 iOff, void *p){
  return SQLITE_OK;
}

/*
** Install the VFS wrapper around the file-descriptor open on the input
** database for recover handle p. Mutex RECOVER_MUTEX_ID must be held
** when this function is called.
*/
static void recoverInstallWrapper(sqlite3_recover *p){
  sqlite3_file *pFd = 0;
  assert( recover_g.pMethods==0 );
  recoverAssertMutexHeld();
  sqlite3_file_control(p->dbIn, p->zDb, SQLITE_FCNTL_FILE_POINTER, (void*)&pFd);
  assert( pFd==0 || pFd->pMethods!=&recover_methods );
  if( pFd && pFd->pMethods ){
    int iVersion = 1 + (pFd->pMethods->iVersion>1 && pFd->pMethods->xShmMap!=0);
    recover_g.pMethods = pFd->pMethods;
    recover_g.p = p;
    recover_methods.iVersion = iVersion;
    pFd->pMethods = &recover_methods;
  }
}

/*
** Uninstall the VFS wrapper that was installed around the file-descriptor open
** on the input database for recover handle p. Mutex RECOVER_MUTEX_ID must be
** held when this function is called.
*/
static void recoverUninstallWrapper(sqlite3_recover *p){
  sqlite3_file *pFd = 0;
  recoverAssertMutexHeld();
  sqlite3_file_control(p->dbIn, p->zDb,SQLITE_FCNTL_FILE_POINTER,(void*)&pFd);
  if( pFd && pFd->pMethods ){
    pFd->pMethods = recover_g.pMethods;
    recover_g.pMethods = 0;
    recover_g.p = 0;
  }
}

/*
** This function does the work of a single sqlite3_recover_step() call. It
** is guaranteed that the handle is not in an error state when this
** function is called.
*/
static void recoverStep(sqlite3_recover *p){
  assert( p && p->errCode==SQLITE_OK );
  switch( p->eState ){
    case RECOVER_STATE_INIT:
      /* This is the very first call to sqlite3_recover_step() on this object.
      */
      recoverSqlCallback(p, "BEGIN");
      recoverSqlCallback(p, "PRAGMA writable_schema = on");

      recoverEnterMutex();
      recoverInstallWrapper(p);

      /* Open the output database. And register required virtual tables and 
      ** user functions with the new handle. */
      recoverOpenOutput(p);

      /* Open transactions on both the input and output databases. */
      recoverExec(p, p->dbIn, "PRAGMA writable_schema = on");
      recoverExec(p, p->dbIn, "BEGIN");
      if( p->errCode==SQLITE_OK ) p->bCloseTransaction = 1;
      recoverExec(p, p->dbIn, "SELECT 1 FROM sqlite_schema");
      recoverTransferSettings(p);
      recoverOpenRecovery(p);
      recoverCacheSchema(p);

      recoverUninstallWrapper(p);
      recoverLeaveMutex();

      recoverExec(p, p->dbOut, "BEGIN");

      recoverWriteSchema1(p);
      p->eState = RECOVER_STATE_WRITING;
      break;
      
    case RECOVER_STATE_WRITING: {
      if( p->w1.pTbls==0 ){
        recoverWriteDataInit(p);
      }
      if( SQLITE_DONE==recoverWriteDataStep(p) ){
        recoverWriteDataCleanup(p);
        if( p->zLostAndFound ){
          p->eState = RECOVER_STATE_LOSTANDFOUND1;
        }else{
          p->eState = RECOVER_STATE_SCHEMA2;
        }
      }
      break;
    }

    case RECOVER_STATE_LOSTANDFOUND1: {
      if( p->laf.pUsed==0 ){
        recoverLostAndFound1Init(p);
      }
      if( SQLITE_DONE==recoverLostAndFound1Step(p) ){
        p->eState = RECOVER_STATE_LOSTANDFOUND2;
      }
      break;
    }
    case RECOVER_STATE_LOSTANDFOUND2: {
      if( p->laf.pAllAndParent==0 ){
        recoverLostAndFound2Init(p);
      }
      if( SQLITE_DONE==recoverLostAndFound2Step(p) ){
        p->eState = RECOVER_STATE_LOSTANDFOUND3;
      }
      break;
    }

    case RECOVER_STATE_LOSTANDFOUND3: {
      if( p->laf.pInsert==0 ){
        recoverLostAndFound3Init(p);
      }
      if( SQLITE_DONE==recoverLostAndFound3Step(p) ){
        p->eState = RECOVER_STATE_SCHEMA2;
      }
      break;
    }

    case RECOVER_STATE_SCHEMA2: {
      int rc = SQLITE_OK;

      recoverWriteSchema2(p);
      p->eState = RECOVER_STATE_DONE;

      /* If no error has occurred, commit the write transaction on the output
      ** database. Regardless of whether or not an error has occurred, make
      ** an attempt to end the read transaction on the input database.  */
      recoverExec(p, p->dbOut, "COMMIT");
      rc = sqlite3_exec(p->dbIn, "END", 0, 0, 0);
      if( p->errCode==SQLITE_OK ) p->errCode = rc;

      recoverSqlCallback(p, "PRAGMA writable_schema = off");
      recoverSqlCallback(p, "COMMIT");
      p->eState = RECOVER_STATE_DONE;
      recoverFinalCleanup(p);
      break;
    };

    case RECOVER_STATE_DONE: {
      /* no-op */
      break;
    };
  }
}


/*
** This is a worker function that does the heavy lifting for both init
** functions:
**
**     sqlite3_recover_init()
**     sqlite3_recover_init_sql()
**
** All this function does is allocate space for the recover handle and
** take copies of the input parameters. All the real work is done within
** sqlite3_recover_run().
*/
sqlite3_recover *recoverInit(
  sqlite3* db, 
  const char *zDb, 
  const char *zUri,               /* Output URI for _recover_init() */
  int (*xSql)(void*, const char*),/* SQL callback for _recover_init_sql() */
  void *pSqlCtx                   /* Context arg for _recover_init_sql() */
){
  sqlite3_recover *pRet = 0;
  int nDb = 0;
  int nUri = 0;
  int nByte = 0;

  if( zDb==0 ){ zDb = "main"; }

  nDb = recoverStrlen(zDb);
  nUri = recoverStrlen(zUri);

  nByte = sizeof(sqlite3_recover) + nDb+1 + nUri+1;
  pRet = (sqlite3_recover*)sqlite3_malloc(nByte);
  if( pRet ){
    memset(pRet, 0, nByte);
    pRet->dbIn = db;
    pRet->zDb = (char*)&pRet[1];
    pRet->zUri = &pRet->zDb[nDb+1];
    memcpy(pRet->zDb, zDb, nDb);
    if( nUri>0 && zUri ) memcpy(pRet->zUri, zUri, nUri);
    pRet->xSql = xSql;
    pRet->pSqlCtx = pSqlCtx;
    pRet->bRecoverRowid = RECOVER_ROWID_DEFAULT;
  }

  return pRet;
}

/*
** Initialize a recovery handle that creates a new database containing
** the recovered data.
*/
sqlite3_recover *sqlite3_recover_init(
  sqlite3* db, 
  const char *zDb, 
  const char *zUri
){
  return recoverInit(db, zDb, zUri, 0, 0);
}

/*
** Initialize a recovery handle that returns recovered data in the
** form of SQL statements via a callback.
*/
sqlite3_recover *sqlite3_recover_init_sql(
  sqlite3* db, 
  const char *zDb, 
  int (*xSql)(void*, const char*),
  void *pSqlCtx
){
  return recoverInit(db, zDb, 0, xSql, pSqlCtx);
}

/*
** Return the handle error message, if any.
*/
const char *sqlite3_recover_errmsg(sqlite3_recover *p){
  return (p && p->errCode!=SQLITE_NOMEM) ? p->zErrMsg : "out of memory";
}

/*
** Return the handle error code.
*/
int sqlite3_recover_errcode(sqlite3_recover *p){
  return p ? p->errCode : SQLITE_NOMEM;
}

/*
** Configure the handle.
*/
int sqlite3_recover_config(sqlite3_recover *p, int op, void *pArg){
  int rc = SQLITE_OK;
  if( p==0 ){
    rc = SQLITE_NOMEM;
  }else if( p->eState!=RECOVER_STATE_INIT ){
    rc = SQLITE_MISUSE;
  }else{
    switch( op ){
      case 789:
        /* This undocumented magic configuration option is used to set the
        ** name of the auxiliary database that is ATTACH-ed to the database
        ** connection and used to hold state information during the
        ** recovery process.  This option is for debugging use only and
        ** is subject to change or removal at any time. */
        sqlite3_free(p->zStateDb);
        p->zStateDb = recoverMPrintf(p, "%s", (char*)pArg);
        break;

      case SQLITE_RECOVER_LOST_AND_FOUND: {
        const char *zArg = (const char*)pArg;
        sqlite3_free(p->zLostAndFound);
        if( zArg ){
          p->zLostAndFound = recoverMPrintf(p, "%s", zArg);
        }else{
          p->zLostAndFound = 0;
        }
        break;
      }

      case SQLITE_RECOVER_FREELIST_CORRUPT:
        p->bFreelistCorrupt = *(int*)pArg;
        break;

      case SQLITE_RECOVER_ROWIDS:
        p->bRecoverRowid = *(int*)pArg;
        break;

      case SQLITE_RECOVER_SLOWINDEXES:
        p->bSlowIndexes = *(int*)pArg;
        break;

      default:
        rc = SQLITE_NOTFOUND;
        break;
    }
  }

  return rc;
}

/*
** Do a unit of work towards the recovery job. Return SQLITE_OK if
** no error has occurred but database recovery is not finished, SQLITE_DONE
** if database recovery has been successfully completed, or an SQLite
** error code if an error has occurred.
*/
int sqlite3_recover_step(sqlite3_recover *p){
  if( p==0 ) return SQLITE_NOMEM;
  if( p->errCode==SQLITE_OK ) recoverStep(p);
  if( p->eState==RECOVER_STATE_DONE && p->errCode==SQLITE_OK ){
    return SQLITE_DONE;
  }
  return p->errCode;
}

/*
** Do the configured recovery operation. Return SQLITE_OK if successful, or
** else an SQLite error code.
*/
int sqlite3_recover_run(sqlite3_recover *p){
  while( SQLITE_OK==sqlite3_recover_step(p) );
  return sqlite3_recover_errcode(p);
}


/*
** Free all resources associated with the recover handle passed as the only
** argument. The results of using a handle with any sqlite3_recover_**
** API function after it has been passed to this function are undefined.
**
** A copy of the value returned by the first call made to sqlite3_recover_run()
** on this handle is returned, or SQLITE_OK if sqlite3_recover_run() has
** not been called on this handle.
*/
int sqlite3_recover_finish(sqlite3_recover *p){
  int rc;
  if( p==0 ){
    rc = SQLITE_NOMEM;
  }else{
    recoverFinalCleanup(p);
    if( p->bCloseTransaction && sqlite3_get_autocommit(p->dbIn)==0 ){
      rc = sqlite3_exec(p->dbIn, "END", 0, 0, 0);
      if( p->errCode==SQLITE_OK ) p->errCode = rc;
    }
    rc = p->errCode;
    sqlite3_free(p->zErrMsg);
    sqlite3_free(p->zStateDb);
    sqlite3_free(p->zLostAndFound);
    sqlite3_free(p->pPage1Cache);
    sqlite3_free(p);
  }
  return rc;
}

#endif /* ifndef SQLITE_OMIT_VIRTUALTABLE */

/************************* End ../ext/recover/sqlite3recover.c ********************/
#endif

#if defined(SQLITE_ENABLE_SESSION)
/*
** State information for a single open session
*/
typedef struct OpenSession OpenSession;

    *pAuxDb;             /* Currently active database connection */
  int *aiIndent;         /* Array of indents used in MODE_Explain */
  int nIndent;           /* Size of array aiIndent[] */
  int iIndent;           /* Index of current op in aiIndent[] */
  char *zNonce;          /* Nonce for temporary safe-mode excapes */
  EQPGraph sGraph;       /* Information for the graphical EXPLAIN QUERY PLAN */
  ExpertInfo expert;     /* Valid if previous command was ".expert OPT..." */
#ifdef SQLITE_SHELL_FIDDLE
  struct {
    const char * zInput; /* Input string from wasm/JS proxy */
    const char * zPos;   /* Cursor pos into zInput */
    const char * zDefaultDbName; /* Default name for db file */
  } wasm;
#endif
};

#ifdef SQLITE_SHELL_FIDDLE
static ShellState shellState;
#endif


/* Allowed values for ShellState.autoEQP
*/
#define AUTOEQP_off      0           /* Automatic EXPLAIN QUERY PLAN is off */

}

/*
** Output the given string as a hex-encoded blob (eg. X'1234' )
*/
static void output_hex_blob(FILE *out, const void *pBlob, int nBlob){
  int i;
  unsigned char *aBlob = (unsigned char*)pBlob;

  char *zStr = sqlite3_malloc(nBlob*2 + 1);
  shell_check_oom(zStr);

  for(i=0; i<nBlob; i++){
    static const char aHex[] = {
        '0', '1', '2', '3', '4', '5', '6', '7',
        '8', '9', 'a', 'b', 'c', 'd', 'e', 'f'
    };
    zStr[i*2] = aHex[ (aBlob[i] >> 4) ];
    zStr[i*2+1] = aHex[ (aBlob[i] & 0x0F) ];
  }
  zStr[i*2] = '\0';

  raw_printf(out,"X'%s'", zStr);
  sqlite3_free(zStr);
}

/*
** Find a string that is not found anywhere in z[].  Return a pointer
** to that string.
**
** Try to use zA and zB first.  If both of those are already found in z[]

  }
  fputc('"', out);
}

/*
** Output the given string as a quoted according to JSON quoting rules.
*/
static void output_json_string(FILE *out, const char *z, i64 n){
  unsigned int c;
  if( n<0 ) n = strlen(z);
  fputc('"', out);
  while( n-- ){
    c = *(z++);
    if( c=='\\' || c=='"' ){
      fputc('\\', out);
      fputc(c, out);
    }else if( c<=0x1f ){

    "zipfile_cds",
  };
  UNUSED_PARAMETER(zA2);
  UNUSED_PARAMETER(zA3);
  UNUSED_PARAMETER(zA4);
  switch( op ){
    case SQLITE_ATTACH: {
#ifndef SQLITE_SHELL_FIDDLE
      /* In WASM builds the filesystem is a virtual sandbox, so
      ** there's no harm in using ATTACH. */
      failIfSafeMode(p, "cannot run ATTACH in safe mode");
#endif
      break;
    }
    case SQLITE_FUNCTION: {

#endif

/*
** Print a schema statement.  Part of MODE_Semi and MODE_Pretty output.
**
** This routine converts some CREATE TABLE statements for shadow tables
** in FTS3/4/5 into CREATE TABLE IF NOT EXISTS statements.
**
** If the schema statement in z[] contains a start-of-comment and if
** sqlite3_complete() returns false, try to terminate the comment before
** printing the result.  https://sqlite.org/forum/forumpost/d7be961c5c
*/
static void printSchemaLine(FILE *out, const char *z, const char *zTail){
  char *zToFree = 0;
  if( z==0 ) return;
  if( zTail==0 ) return;
  if( zTail[0]==';' && (strstr(z, "/*")!=0 || strstr(z,"--")!=0) ){
    const char *zOrig = z;
    static const char *azTerm[] = { "", "*/", "\n" };
    int i;
    for(i=0; i<ArraySize(azTerm); i++){
      char *zNew = sqlite3_mprintf("%s%s;", zOrig, azTerm[i]);
      if( sqlite3_complete(zNew) ){
        size_t n = strlen(zNew);
        zNew[n-1] = 0;
        zToFree = zNew;
        z = zNew;
        break;
      }
      sqlite3_free(zNew);
    }
  }
  if( sqlite3_strglob("CREATE TABLE ['\"]*", z)==0 ){
    utf8_printf(out, "CREATE TABLE IF NOT EXISTS %s%s", z+13, zTail);
  }else{
    utf8_printf(out, "%s%s", z, zTail);
  }
  sqlite3_free(zToFree);
}
static void printSchemaLineN(FILE *out, char *z, int n, const char *zTail){
  char c = z[n];
  z[n] = 0;
  printSchemaLine(out, z, zTail);
  z[n] = c;
}

}

/*
** Add a new entry to the EXPLAIN QUERY PLAN data
*/
static void eqp_append(ShellState *p, int iEqpId, int p2, const char *zText){
  EQPGraphRow *pNew;
  i64 nText;
  if( zText==0 ) return;
  nText = strlen(zText);
  if( p->autoEQPtest ){
    utf8_printf(p->out, "%d,%d,%s\n", iEqpId, p2, zText);
  }
  pNew = sqlite3_malloc64( sizeof(*pNew) + nText );
  shell_check_oom(pNew);
  pNew->iEqpId = iEqpId;
  pNew->iParentId = p2;

}

/* Render a single level of the graph that has iEqpId as its parent.  Called
** recursively to render sublevels.
*/
static void eqp_render_level(ShellState *p, int iEqpId){
  EQPGraphRow *pRow, *pNext;
  i64 n = strlen(p->sGraph.zPrefix);
  char *z;
  for(pRow = eqp_next_row(p, iEqpId, 0); pRow; pRow = pNext){
    pNext = eqp_next_row(p, iEqpId, pRow);
    z = pRow->zText;
    utf8_printf(p->out, "%s%s%s\n", p->sGraph.zPrefix,
                pNext ? "|--" : "`--", z);
    if( n<(i64)sizeof(p->sGraph.zPrefix)-7 ){
      memcpy(&p->sGraph.zPrefix[n], pNext ? "|  " : "   ", 4);
      eqp_render_level(p, pRow->iEqpId);
      p->sGraph.zPrefix[n] = 0;
    }
  }
}

  }
  len = strlen(zSql);
  if( len>78 ){
    len = 78;
    while( (zSql[len]&0xc0)==0x80 ) len--;
  }
  zCode = sqlite3_mprintf("%.*s", len, zSql);
  shell_check_oom(zCode);
  for(i=0; zCode[i]; i++){ if( IsSpace(zSql[i]) ) zCode[i] = ' '; }
  if( iOffset<25 ){
    zMsg = sqlite3_mprintf("\n  %z\n  %*s^--- error here", zCode, iOffset, "");
  }else{
    zMsg = sqlite3_mprintf("\n  %z\n  %*serror here ---^", zCode, iOffset-14, "");
  }
  return zMsg;

      { "read_bytes: ",             "Bytes read from storage:"  },
      { "write_bytes: ",            "Bytes written to storage:" },
      { "cancelled_write_bytes: ",  "Cancelled write bytes:"    },
    };
    int i;
    for(i=0; i<ArraySize(aTrans); i++){
      int n = strlen30(aTrans[i].zPattern);
      if( cli_strncmp(aTrans[i].zPattern, z, n)==0 ){
        utf8_printf(out, "%-36s %s", aTrans[i].zDesc, &z[n]);
        break;
      }
    }
  }
  fclose(in);
}

** points to a single nul-terminated string. Return non-zero if zStr
** is equal, according to strcmp(), to any of the strings in the array.
** Otherwise, return zero.
*/
static int str_in_array(const char *zStr, const char **azArray){
  int i;
  for(i=0; azArray[i]; i++){
    if( 0==cli_strcmp(zStr, azArray[i]) ) return 1;
  }
  return 0;
}

/*
** If compiled statement pSql appears to be an EXPLAIN statement, allocate
** and populate the ShellState.aiIndent[] array with the number of

      if( iOp==0 ){
        /* Do further verfication that this is explain output.  Abort if
        ** it is not */
        static const char *explainCols[] = {
           "addr", "opcode", "p1", "p2", "p3", "p4", "p5", "comment" };
        int jj;
        for(jj=0; jj<ArraySize(explainCols); jj++){
          if( cli_strcmp(sqlite3_column_name(pSql,jj),explainCols[jj])!=0 ){
            p->cMode = p->mode;
            sqlite3_reset(pSql);
            return;
          }
        }
      }
      nAlloc += 100;

  memset(&pState->expert, 0, sizeof(ExpertInfo));

  for(i=1; rc==SQLITE_OK && i<nArg; i++){
    char *z = azArg[i];
    int n;
    if( z[0]=='-' && z[1]=='-' ) z++;
    n = strlen30(z);
    if( n>=2 && 0==cli_strncmp(z, "-verbose", n) ){
      pState->expert.bVerbose = 1;
    }
    else if( n>=2 && 0==cli_strncmp(z, "-sample", n) ){
      if( i==(nArg-1) ){
        raw_printf(stderr, "option requires an argument: %s\n", z);
        rc = SQLITE_ERROR;
      }else{
        iSample = (int)integerValue(azArg[++i]);
        if( iSample<0 || iSample>100 ){
          raw_printf(stderr, "value out of range: %s\n", azArg[i]);

  int noSys;

  UNUSED_PARAMETER(azNotUsed);
  if( nArg!=3 || azArg==0 ) return 0;
  zTable = azArg[0];
  zType = azArg[1];
  zSql = azArg[2];
  if( zTable==0 ) return 0;
  if( zType==0 ) return 0;
  dataOnly = (p->shellFlgs & SHFLG_DumpDataOnly)!=0;
  noSys    = (p->shellFlgs & SHFLG_DumpNoSys)!=0;

  if( cli_strcmp(zTable, "sqlite_sequence")==0 && !noSys ){
    if( !dataOnly ) raw_printf(p->out, "DELETE FROM sqlite_sequence;\n");
  }else if( sqlite3_strglob("sqlite_stat?", zTable)==0 && !noSys ){
    if( !dataOnly ) raw_printf(p->out, "ANALYZE sqlite_schema;\n");
  }else if( cli_strncmp(zTable, "sqlite_", 7)==0 ){
    return 0;
  }else if( dataOnly ){
    /* no-op */
  }else if( cli_strncmp(zSql, "CREATE VIRTUAL TABLE", 20)==0 ){
    char *zIns;
    if( !p->writableSchema ){
      raw_printf(p->out, "PRAGMA writable_schema=ON;\n");
      p->writableSchema = 1;
    }
    zIns = sqlite3_mprintf(
       "INSERT INTO sqlite_schema(type,name,tbl_name,rootpage,sql)"
       "VALUES('table','%q','%q',0,'%q');",
       zTable, zTable, zSql);
    shell_check_oom(zIns);
    utf8_printf(p->out, "%s\n", zIns);
    sqlite3_free(zIns);
    return 0;
  }else{
    printSchemaLine(p->out, zSql, ";\n");
  }

  if( cli_strcmp(zType, "table")==0 ){
    ShellText sSelect;
    ShellText sTable;
    char **azCol;
    int i;
    char *savedDestTable;
    int savedMode;

** with ".".  Subsequent lines are supplemental information.
**
** There must be two or more spaces between the end of the command and the
** start of the description of what that command does.
*/
static const char *(azHelp[]) = {
#if defined(SQLITE_HAVE_ZLIB) && !defined(SQLITE_OMIT_VIRTUALTABLE) \
  && !defined(SQLITE_SHELL_FIDDLE)
  ".archive ...             Manage SQL archives",
  "   Each command must have exactly one of the following options:",
  "     -c, --create               Create a new archive",
  "     -u, --update               Add or update files with changed mtime",
  "     -i, --insert               Like -u but always add even if unchanged",
  "     -r, --remove               Remove files from archive",
  "     -t, --list                 List contents of archive",

  "     .ar -xvf ARCHIVE         # Verbosely extract files from ARCHIVE",
  "   See also:",
  "      http://sqlite.org/cli.html#sqlite_archive_support",
#endif
#ifndef SQLITE_OMIT_AUTHORIZATION
  ".auth ON|OFF             Show authorizer callbacks",
#endif
#ifndef SQLITE_SHELL_FIDDLE
  ".backup ?DB? FILE        Backup DB (default \"main\") to FILE",
  "   Options:",
  "       --append            Use the appendvfs",
  "       --async             Write to FILE without journal and fsync()",
#endif
  ".bail on|off             Stop after hitting an error.  Default OFF",
  ".binary on|off           Turn binary output on or off.  Default OFF",
#ifndef SQLITE_SHELL_FIDDLE
  ".cd DIRECTORY            Change the working directory to DIRECTORY",
#endif
  ".changes on|off          Show number of rows changed by SQL",
#ifndef SQLITE_SHELL_FIDDLE
  ".check GLOB              Fail if output since .testcase does not match",
  ".clone NEWDB             Clone data into NEWDB from the existing database",
#endif
  ".connection [close] [#]  Open or close an auxiliary database connection",
  ".databases               List names and files of attached databases",
  ".dbconfig ?op? ?val?     List or change sqlite3_db_config() options",
#if SQLITE_SHELL_HAVE_RECOVER
  ".dbinfo ?DB?             Show status information about the database",
#endif
  ".dump ?OBJECTS?          Render database content as SQL",
  "   Options:",
  "     --data-only            Output only INSERT statements",
  "     --newlines             Allow unescaped newline characters in output",
  "     --nosys                Omit system tables (ex: \"sqlite_stat1\")",
  "     --preserve-rowids      Include ROWID values in the output",
  "   OBJECTS is a LIKE pattern for tables, indexes, triggers or views to dump",
  "   Additional LIKE patterns can be given in subsequent arguments",
  ".echo on|off             Turn command echo on or off",
  ".eqp on|off|full|...     Enable or disable automatic EXPLAIN QUERY PLAN",
  "   Other Modes:",
#ifdef SQLITE_DEBUG
  "      test                  Show raw EXPLAIN QUERY PLAN output",
  "      trace                 Like \"full\" but enable \"PRAGMA vdbe_trace\"",
#endif
  "      trigger               Like \"full\" but also show trigger bytecode",
#ifndef SQLITE_SHELL_FIDDLE
  ".excel                   Display the output of next command in spreadsheet",
  "   --bom                   Put a UTF8 byte-order mark on intermediate file",
#endif
#ifndef SQLITE_SHELL_FIDDLE
  ".exit ?CODE?             Exit this program with return-code CODE",
#endif
  ".expert                  EXPERIMENTAL. Suggest indexes for queries",
  ".explain ?on|off|auto?   Change the EXPLAIN formatting mode.  Default: auto",
  ".filectrl CMD ...        Run various sqlite3_file_control() operations",
  "   --schema SCHEMA         Use SCHEMA instead of \"main\"",
  "   --help                  Show CMD details",
  ".fullschema ?--indent?   Show schema and the content of sqlite_stat tables",
  ".headers on|off          Turn display of headers on or off",
  ".help ?-all? ?PATTERN?   Show help text for PATTERN",
#ifndef SQLITE_SHELL_FIDDLE
  ".import FILE TABLE       Import data from FILE into TABLE",
  "   Options:",
  "     --ascii               Use \\037 and \\036 as column and row separators",
  "     --csv                 Use , and \\n as column and row separators",
  "     --skip N              Skip the first N rows of input",
  "     --schema S            Target table to be S.TABLE",
  "     -v                    \"Verbose\" - increase auxiliary output",

#ifdef SQLITE_ENABLE_IOTRACE
  ".iotrace FILE            Enable I/O diagnostic logging to FILE",
#endif
  ".limit ?LIMIT? ?VAL?     Display or change the value of an SQLITE_LIMIT",
  ".lint OPTIONS            Report potential schema issues.",
  "     Options:",
  "        fkey-indexes     Find missing foreign key indexes",
#if !defined(SQLITE_OMIT_LOAD_EXTENSION) && !defined(SQLITE_SHELL_FIDDLE)
  ".load FILE ?ENTRY?       Load an extension library",
#endif
#ifndef SQLITE_SHELL_FIDDLE
  ".log FILE|off            Turn logging on or off.  FILE can be stderr/stdout",
#endif
  ".mode MODE ?OPTIONS?     Set output mode",
  "   MODE is one of:",
  "     ascii       Columns/rows delimited by 0x1F and 0x1E",
  "     box         Tables using unicode box-drawing characters",
  "     csv         Comma-separated values",
  "     column      Output in columns.  (See .width)",
  "     html        HTML <table> code",
  "     insert      SQL insert statements for TABLE",
  "     json        Results in a JSON array",
  "     line        One value per line",
  "     list        Values delimited by \"|\"",
  "     markdown    Markdown table format",
  "     qbox        Shorthand for \"box --wrap 60 --quote\"",
  "     quote       Escape answers as for SQL",
  "     table       ASCII-art table",
  "     tabs        Tab-separated values",
  "     tcl         TCL list elements",
  "   OPTIONS: (for columnar modes or insert mode):",
  "     --wrap N       Wrap output lines to no longer than N characters",
  "     --wordwrap B   Wrap or not at word boundaries per B (on/off)",
  "     --ww           Shorthand for \"--wordwrap 1\"",
  "     --quote        Quote output text as SQL literals",
  "     --noquote      Do not quote output text",
  "     TABLE          The name of SQL table used for \"insert\" mode",
#ifndef SQLITE_SHELL_FIDDLE
  ".nonce STRING            Suspend safe mode for one command if nonce matches",
#endif
  ".nullvalue STRING        Use STRING in place of NULL values",
#ifndef SQLITE_SHELL_FIDDLE
  ".once ?OPTIONS? ?FILE?   Output for the next SQL command only to FILE",
  "     If FILE begins with '|' then open as a pipe",
  "       --bom  Put a UTF8 byte-order mark at the beginning",
  "       -e     Send output to the system text editor",
  "       -x     Send output as CSV to a spreadsheet (same as \".excel\")",
  /* Note that .open is (partially) available in WASM builds but is
  ** currently only intended to be used by the fiddle tool, not

  "        --hexdb         Load the output of \"dbtotxt\" as an in-memory db",
  "        --maxsize N     Maximum size for --hexdb or --deserialized database",
#endif
  "        --new           Initialize FILE to an empty database",
  "        --nofollow      Do not follow symbolic links",
  "        --readonly      Open FILE readonly",
  "        --zip           FILE is a ZIP archive",
#ifndef SQLITE_SHELL_FIDDLE
  ".output ?FILE?           Send output to FILE or stdout if FILE is omitted",
  "   If FILE begins with '|' then open it as a pipe.",
  "   Options:",
  "     --bom                 Prefix output with a UTF8 byte-order mark",
  "     -e                    Send output to the system text editor",
  "     -x                    Send output as CSV to a spreadsheet",
#endif

  ".progress N              Invoke progress handler after every N opcodes",
  "   --limit N                 Interrupt after N progress callbacks",
  "   --once                    Do no more than one progress interrupt",
  "   --quiet|-q                No output except at interrupts",
  "   --reset                   Reset the count for each input and interrupt",
#endif
  ".prompt MAIN CONTINUE    Replace the standard prompts",
#ifndef SQLITE_SHELL_FIDDLE
  ".quit                    Exit this program",
  ".read FILE               Read input from FILE or command output",
  "    If FILE begins with \"|\", it is a command that generates the input.",
#endif
#if SQLITE_SHELL_HAVE_RECOVER
  ".recover                 Recover as much data as possible from corrupt db.",
  "   --ignore-freelist        Ignore pages that appear to be on db freelist",

  "   --lost-and-found TABLE   Alternative name for the lost-and-found table",
  "   --no-rowids              Do not attempt to recover rowid values",
  "                            that are not also INTEGER PRIMARY KEYs",
#endif
#ifndef SQLITE_SHELL_FIDDLE
  ".restore ?DB? FILE       Restore content of DB (default \"main\") from FILE",
  ".save ?OPTIONS? FILE     Write database to FILE (an alias for .backup ...)",
#endif
  ".scanstats on|off        Turn sqlite3_stmt_scanstatus() metrics on or off",
  ".schema ?PATTERN?        Show the CREATE statements matching PATTERN",
  "   Options:",
  "      --indent             Try to pretty-print the schema",

  "    Options:",
  "      --schema              Also hash the sqlite_schema table",
  "      --sha3-224            Use the sha3-224 algorithm",
  "      --sha3-256            Use the sha3-256 algorithm (default)",
  "      --sha3-384            Use the sha3-384 algorithm",
  "      --sha3-512            Use the sha3-512 algorithm",
  "    Any other argument is a LIKE pattern for tables to hash",
#if !defined(SQLITE_NOHAVE_SYSTEM) && !defined(SQLITE_SHELL_FIDDLE)
  ".shell CMD ARGS...       Run CMD ARGS... in a system shell",
#endif
  ".show                    Show the current values for various settings",
  ".stats ?ARG?             Show stats or turn stats on or off",
  "   off                      Turn off automatic stat display",
  "   on                       Turn on automatic stat display",
  "   stmt                     Show statement stats",
  "   vmstep                   Show the virtual machine step count only",
#if !defined(SQLITE_NOHAVE_SYSTEM) && !defined(SQLITE_SHELL_FIDDLE)
  ".system CMD ARGS...      Run CMD ARGS... in a system shell",
#endif
  ".tables ?TABLE?          List names of tables matching LIKE pattern TABLE",
#ifndef SQLITE_SHELL_FIDDLE
  ".testcase NAME           Begin redirecting output to 'testcase-out.txt'",
#endif
  ".testctrl CMD ...        Run various sqlite3_test_control() operations",
  "                           Run \".testctrl\" with no arguments for details",
  ".timeout MS              Try opening locked tables for MS milliseconds",
  ".timer on|off            Turn SQL timer on or off",
#ifndef SQLITE_OMIT_TRACE

static int showHelp(FILE *out, const char *zPattern){
  int i = 0;
  int j = 0;
  int n = 0;
  char *zPat;
  if( zPattern==0
   || zPattern[0]=='0'
   || cli_strcmp(zPattern,"-a")==0
   || cli_strcmp(zPattern,"-all")==0
   || cli_strcmp(zPattern,"--all")==0
  ){
    /* Show all commands, but only one line per command */
    if( zPattern==0 ) zPattern = "";
    for(i=0; i<ArraySize(azHelp); i++){
      if( azHelp[i][0]=='.' || zPattern[0] ){
        utf8_printf(out, "%s\n", azHelp[i]);
        n++;

  }
  for(nLine++; fgets(zLine, sizeof(zLine), in)!=0; nLine++){
    rc = sscanf(zLine, "| page %d offset %d", &j, &k);
    if( rc==2 ){
      iOffset = k;
      continue;
    }
    if( cli_strncmp(zLine, "| end ", 6)==0 ){
      break;
    }
    rc = sscanf(zLine,"| %d: %x %x %x %x %x %x %x %x %x %x %x %x %x %x %x %x",
                &j, &x[0], &x[1], &x[2], &x[3], &x[4], &x[5], &x[6], &x[7],
                &x[8], &x[9], &x[10], &x[11], &x[12], &x[13], &x[14], &x[15]);
    if( rc==17 ){
      k = iOffset+j;

readHexDb_error:
  if( in!=p->in ){
    fclose(in);
  }else{
    while( fgets(zLine, sizeof(zLine), p->in)!=0 ){
      nLine++;
      if(cli_strncmp(zLine, "| end ", 6)==0 ) break;
    }
    p->lineno = nLine;
  }
  sqlite3_free(a);
  utf8_printf(stderr,"Error on line %d of --hexdb input\n", nLine);
  return 0;
}

  sqlite3_context *context, 
  int argc, 
  sqlite3_value **argv
){
  const char *zText = (const char*)sqlite3_value_text(argv[0]);
  UNUSED_PARAMETER(argc);
  if( zText && zText[0]=='\'' ){
    i64 nText = sqlite3_value_bytes(argv[0]);
    i64 i;
    char zBuf1[20];
    char zBuf2[20];
    const char *zNL = 0;
    const char *zCR = 0;
    i64 nCR = 0;
    i64 nNL = 0;

    for(i=0; zText[i]; i++){
      if( zNL==0 && zText[i]=='\n' ){
        zNL = unused_string(zText, "\\n", "\\012", zBuf1);
        nNL = strlen(zNL);
      }
      if( zCR==0 && zText[i]=='\r' ){
        zCR = unused_string(zText, "\\r", "\\015", zBuf2);
        nCR = strlen(zCR);
      }
    }

    if( zNL || zCR ){
      i64 iOut = 0;
      i64 nMax = (nNL > nCR) ? nNL : nCR;
      i64 nAlloc = nMax * nText + (nMax+64)*2;
      char *zOut = (char*)sqlite3_malloc64(nAlloc);
      if( zOut==0 ){
        sqlite3_result_error_nomem(context);
        return;
      }

#endif
    sqlite3_shathree_init(p->db, 0, 0);
    sqlite3_uint_init(p->db, 0, 0);
    sqlite3_decimal_init(p->db, 0, 0);
    sqlite3_regexp_init(p->db, 0, 0);
    sqlite3_ieee_init(p->db, 0, 0);
    sqlite3_series_init(p->db, 0, 0);
#ifndef SQLITE_SHELL_FIDDLE
    sqlite3_fileio_init(p->db, 0, 0);
    sqlite3_completion_init(p->db, 0, 0);
#endif
#if SQLITE_SHELL_HAVE_RECOVER
    sqlite3_dbdata_init(p->db, 0, 0);
#endif
#ifdef SQLITE_HAVE_ZLIB
    if( !p->bSafeModePersist ){
      sqlite3_zipfile_init(p->db, 0, 0);
      sqlite3_sqlar_init(p->db, 0, 0);
    }

}

#elif HAVE_LINENOISE
/*
** Linenoise completion callback
*/
static void linenoise_completion(const char *zLine, linenoiseCompletions *lc){
  i64 nLine = strlen(zLine);
  i64 i, iStart;
  sqlite3_stmt *pStmt = 0;
  char *zSql;
  char zBuf[1000];

  if( nLine>sizeof(zBuf)-30 ) return;
  if( zLine[0]=='.' || zLine[0]=='#') return;
  for(i=nLine-1; i>=0 && (isalnum(zLine[i]) || zLine[i]=='_'); i--){}

/*
** Try to open an output file.   The names "stdout" and "stderr" are
** recognized and do the right thing.  NULL is returned if the output
** filename is "off".
*/
static FILE *output_file_open(const char *zFile, int bTextMode){
  FILE *f;
  if( cli_strcmp(zFile,"stdout")==0 ){
    f = stdout;
  }else if( cli_strcmp(zFile, "stderr")==0 ){
    f = stderr;
  }else if( cli_strcmp(zFile, "off")==0 ){
    f = 0;
  }else{
    f = fopen(zFile, bTextMode ? "w" : "wb");
    if( f==0 ){
      utf8_printf(stderr, "Error: cannot open \"%s\"\n", zFile);
    }
  }

  void *pArg,             /* The ShellState pointer */
  void *pP,               /* Usually a pointer to sqlite_stmt */
  void *pX                /* Auxiliary output */
){
  ShellState *p = (ShellState*)pArg;
  sqlite3_stmt *pStmt;
  const char *zSql;
  i64 nSql;
  if( p->traceOut==0 ) return 0;
  if( mType==SQLITE_TRACE_CLOSE ){
    utf8_printf(p->traceOut, "-- closing database connection\n");
    return 0;
  }
  if( mType!=SQLITE_TRACE_ROW && ((const char*)pX)[0]=='-' ){
    zSql = (const char*)pX;

      default: {
        zSql = sqlite3_sql(pStmt);
        break;
      }
    }
  }
  if( zSql==0 ) return 0;
  nSql = strlen(zSql);
  if( nSql>1000000000 ) nSql = 1000000000;
  while( nSql>0 && zSql[nSql-1]==';' ){ nSql--; }
  switch( mType ){
    case SQLITE_TRACE_ROW:
    case SQLITE_TRACE_STMT: {
      utf8_printf(p->traceOut, "%.*s;\n", (int)nSql, zSql);
      break;
    }
    case SQLITE_TRACE_PROFILE: {
      sqlite3_int64 nNanosec = *(sqlite3_int64*)pX;
      utf8_printf(p->traceOut, "%.*s; -- %lld ns\n", (int)nSql, zSql, nNanosec);
      break;
    }
  }
  return 0;
}
#endif

        if( val==3 ) raw_printf(p->out, " (utf16be)");
      }
    }
    raw_printf(p->out, "\n");
  }
  if( zDb==0 ){
    zSchemaTab = sqlite3_mprintf("main.sqlite_schema");
  }else if( cli_strcmp(zDb,"temp")==0 ){
    zSchemaTab = sqlite3_mprintf("%s", "sqlite_temp_schema");
  }else{
    zSchemaTab = sqlite3_mprintf("\"%w\".sqlite_schema", zDb);
  }
  for(i=0; i<ArraySize(aQuery); i++){
    char *zSql = sqlite3_mprintf(aQuery[i].zSql, zSchemaTab);
    int val = db_int(p->db, zSql);
    sqlite3_free(zSql);
    utf8_printf(p->out, "%-20s %d\n", aQuery[i].zName, val);
  }
  sqlite3_free(zSchemaTab);
  sqlite3_file_control(p->db, zDb, SQLITE_FCNTL_DATA_VERSION, &iDataVersion);
  utf8_printf(p->out, "%-20s %u\n", "data version", iDataVersion);
  return 0;
}
#endif /* SQLITE_SHELL_HAVE_RECOVER */


/*
** Print the current sqlite3_errmsg() value to stderr and return 1.
*/
static int shellDatabaseError(sqlite3 *db){
  const char *zErr = sqlite3_errmsg(db);
  utf8_printf(stderr, "Error: %s\n", zErr);

** Compare the string as a command-line option with either one or two
** initial "-" characters.
*/
static int optionMatch(const char *zStr, const char *zOpt){
  if( zStr[0]!='-' ) return 0;
  zStr++;
  if( zStr[0]=='-' ) zStr++;
  return cli_strcmp(zStr, zOpt)==0;
}

/*
** Delete a file.
*/
int shellDeleteFile(const char *zFilename){
  int rc;

  return rc;
}
/* End of the ".archive" or ".ar" command logic
*******************************************************************************/
#endif /* !defined(SQLITE_OMIT_VIRTUALTABLE) && defined(SQLITE_HAVE_ZLIB) */























































































































































#if SQLITE_SHELL_HAVE_RECOVER















































































































































/*

** This function is used as a callback by the recover extension. Simply
** print the supplied SQL statement to stdout.
*/









static int recoverSqlCb(void *pCtx, const char *zSql){


















  ShellState *pState = (ShellState*)pCtx;



















  utf8_printf(pState->out, "%s;\n", zSql);











  return SQLITE_OK;
}

/*
** This function is called to recover data from the database. A script
** to construct a new database containing all recovered data is output
** on stream pState->out.
*/
static int recoverDatabaseCmd(ShellState *pState, int nArg, char **azArg){
  int rc = SQLITE_OK;



  const char *zRecoveryDb = "";   /* Name of "recovery" database.  Debug only */
  const char *zLAF = "lost_and_found";




  int bFreelist = 1;              /* 0 if --ignore-freelist is specified */
  int bRowids = 1;                /* 0 if --no-rowids */
  sqlite3_recover *p = 0;
  int i = 0;

  for(i=1; i<nArg; i++){
    char *z = azArg[i];
    int n;
    if( z[0]=='-' && z[1]=='-' ) z++;
    n = strlen30(z);
    if( n<=17 && memcmp("-ignore-freelist", z, n)==0 ){
      bFreelist = 0;
    }else
    if( n<=12 && memcmp("-recovery-db", z, n)==0 && i<(nArg-1) ){
      /* This option determines the name of the ATTACH-ed database used
      ** internally by the recovery extension.  The default is "" which
      ** means to use a temporary database that is automatically deleted
      ** when closed.  This option is undocumented and might disappear at
      ** any moment. */
      i++;
      zRecoveryDb = azArg[i];
    }else
    if( n<=15 && memcmp("-lost-and-found", z, n)==0 && i<(nArg-1) ){
      i++;
      zLAF = azArg[i];
    }else
    if( n<=10 && memcmp("-no-rowids", z, n)==0 ){
      bRowids = 0;
    }
    else{
      utf8_printf(stderr, "unexpected option: %s\n", azArg[i]); 
      showHelp(pState->out, azArg[0]);
      return 1;
    }
  }












  p = sqlite3_recover_init_sql(

      pState->db, "main", recoverSqlCb, (void*)pState



























































































































  );



  sqlite3_recover_config(p, 789, (void*)zRecoveryDb);  /* Debug use only */











  sqlite3_recover_config(p, SQLITE_RECOVER_LOST_AND_FOUND, (void*)zLAF);



  sqlite3_recover_config(p, SQLITE_RECOVER_ROWIDS, (void*)&bRowids);








  sqlite3_recover_config(p, SQLITE_RECOVER_FREELIST_CORRUPT,(void*)&bFreelist);




















































  sqlite3_recover_run(p);
























  if( sqlite3_recover_errcode(p)!=SQLITE_OK ){






    const char *zErr = sqlite3_recover_errmsg(p);







    int errCode = sqlite3_recover_errcode(p);

    raw_printf(stderr, "sql error: %s (%d)\n", zErr, errCode);
  }



  rc = sqlite3_recover_finish(p);





  return rc;
}
#endif /* SQLITE_SHELL_HAVE_RECOVER */


/*
 * zAutoColumn(zCol, &db, ?) => Maybe init db, add column zCol to it.
 * zAutoColumn(0, &db, ?) => (db!=0) Form columns spec for CREATE TABLE,
 *   close db and set it to 0, and return the columns spec, to later
 *   be sqlite3_free()'ed by the caller.

  */
  if( nArg==0 ) return 0; /* no tokens, no error */
  n = strlen30(azArg[0]);
  c = azArg[0][0];
  clearTempFile(p);

#ifndef SQLITE_OMIT_AUTHORIZATION
  if( c=='a' && cli_strncmp(azArg[0], "auth", n)==0 ){
    if( nArg!=2 ){
      raw_printf(stderr, "Usage: .auth ON|OFF\n");
      rc = 1;
      goto meta_command_exit;
    }
    open_db(p, 0);
    if( booleanValue(azArg[1]) ){
      sqlite3_set_authorizer(p->db, shellAuth, p);
    }else if( p->bSafeModePersist ){
      sqlite3_set_authorizer(p->db, safeModeAuth, p);
    }else{
      sqlite3_set_authorizer(p->db, 0, 0);
    }
  }else
#endif

#if !defined(SQLITE_OMIT_VIRTUALTABLE) && defined(SQLITE_HAVE_ZLIB) \
  && !defined(SQLITE_SHELL_FIDDLE)
  if( c=='a' && cli_strncmp(azArg[0], "archive", n)==0 ){
    open_db(p, 0);
    failIfSafeMode(p, "cannot run .archive in safe mode");
    rc = arDotCommand(p, 0, azArg, nArg);
  }else
#endif

#ifndef SQLITE_SHELL_FIDDLE
  if( (c=='b' && n>=3 && cli_strncmp(azArg[0], "backup", n)==0)
   || (c=='s' && n>=3 && cli_strncmp(azArg[0], "save", n)==0)
  ){
    const char *zDestFile = 0;
    const char *zDb = 0;
    sqlite3 *pDest;
    sqlite3_backup *pBackup;
    int j;
    int bAsync = 0;
    const char *zVfs = 0;
    failIfSafeMode(p, "cannot run .%s in safe mode", azArg[0]);
    for(j=1; j<nArg; j++){
      const char *z = azArg[j];
      if( z[0]=='-' ){
        if( z[1]=='-' ) z++;
        if( cli_strcmp(z, "-append")==0 ){
          zVfs = "apndvfs";
        }else
        if( cli_strcmp(z, "-async")==0 ){
          bAsync = 1;
        }else
        {
          utf8_printf(stderr, "unknown option: %s\n", azArg[j]);
          return 1;
        }
      }else if( zDestFile==0 ){

      rc = 0;
    }else{
      utf8_printf(stderr, "Error: %s\n", sqlite3_errmsg(pDest));
      rc = 1;
    }
    close_db(pDest);
  }else
#endif /* !defined(SQLITE_SHELL_FIDDLE) */

  if( c=='b' && n>=3 && cli_strncmp(azArg[0], "bail", n)==0 ){
    if( nArg==2 ){
      bail_on_error = booleanValue(azArg[1]);
    }else{
      raw_printf(stderr, "Usage: .bail on|off\n");
      rc = 1;
    }
  }else

  if( c=='b' && n>=3 && cli_strncmp(azArg[0], "binary", n)==0 ){
    if( nArg==2 ){
      if( booleanValue(azArg[1]) ){
        setBinaryMode(p->out, 1);
      }else{
        setTextMode(p->out, 1);
      }
    }else{
      raw_printf(stderr, "Usage: .binary on|off\n");
      rc = 1;
    }
  }else

  /* The undocumented ".breakpoint" command causes a call to the no-op
  ** routine named test_breakpoint().
  */
  if( c=='b' && n>=3 && cli_strncmp(azArg[0], "breakpoint", n)==0 ){
    test_breakpoint();
  }else

#ifndef SQLITE_SHELL_FIDDLE
  if( c=='c' && cli_strcmp(azArg[0],"cd")==0 ){
    failIfSafeMode(p, "cannot run .cd in safe mode");
    if( nArg==2 ){
#if defined(_WIN32) || defined(WIN32)
      wchar_t *z = sqlite3_win32_utf8_to_unicode(azArg[1]);
      rc = !SetCurrentDirectoryW(z);
      sqlite3_free(z);
#else
      rc = chdir(azArg[1]);
#endif
      if( rc ){
        utf8_printf(stderr, "Cannot change to directory \"%s\"\n", azArg[1]);
        rc = 1;
      }
    }else{
      raw_printf(stderr, "Usage: .cd DIRECTORY\n");
      rc = 1;
    }
  }else
#endif /* !defined(SQLITE_SHELL_FIDDLE) */

  if( c=='c' && n>=3 && cli_strncmp(azArg[0], "changes", n)==0 ){
    if( nArg==2 ){
      setOrClearFlag(p, SHFLG_CountChanges, azArg[1]);
    }else{
      raw_printf(stderr, "Usage: .changes on|off\n");
      rc = 1;
    }
  }else

#ifndef SQLITE_SHELL_FIDDLE
  /* Cancel output redirection, if it is currently set (by .testcase)
  ** Then read the content of the testcase-out.txt file and compare against
  ** azArg[1].  If there are differences, report an error and exit.
  */
  if( c=='c' && n>=3 && cli_strncmp(azArg[0], "check", n)==0 ){
    char *zRes = 0;
    output_reset(p);
    if( nArg!=2 ){
      raw_printf(stderr, "Usage: .check GLOB-PATTERN\n");
      rc = 2;
    }else if( (zRes = readFile("testcase-out.txt", 0))==0 ){
      raw_printf(stderr, "Error: cannot read 'testcase-out.txt'\n");
      rc = 2;
    }else if( testcase_glob(azArg[1],zRes)==0 ){
      utf8_printf(stderr,
                 "testcase-%s FAILED\n Expected: [%s]\n      Got: [%s]\n",
                 p->zTestcase, azArg[1], zRes);
      rc = 1;
    }else{
      utf8_printf(stdout, "testcase-%s ok\n", p->zTestcase);
      p->nCheck++;
    }
    sqlite3_free(zRes);
  }else
#endif /* !defined(SQLITE_SHELL_FIDDLE) */

#ifndef SQLITE_SHELL_FIDDLE
  if( c=='c' && cli_strncmp(azArg[0], "clone", n)==0 ){
    failIfSafeMode(p, "cannot run .clone in safe mode");
    if( nArg==2 ){
      tryToClone(p, azArg[1]);
    }else{
      raw_printf(stderr, "Usage: .clone FILENAME\n");
      rc = 1;
    }
  }else
#endif /* !defined(SQLITE_SHELL_FIDDLE) */

  if( c=='c' && cli_strncmp(azArg[0], "connection", n)==0 ){
    if( nArg==1 ){
      /* List available connections */
      int i;
      for(i=0; i<ArraySize(p->aAuxDb); i++){
        const char *zFile = p->aAuxDb[i].zDbFilename;
        if( p->aAuxDb[i].db==0 && p->pAuxDb!=&p->aAuxDb[i] ){
          zFile = "(not open)";

      int i = azArg[1][0] - '0';
      if( p->pAuxDb != &p->aAuxDb[i] && i>=0 && i<ArraySize(p->aAuxDb) ){
        p->pAuxDb->db = p->db;
        p->pAuxDb = &p->aAuxDb[i];
        globalDb = p->db = p->pAuxDb->db;
        p->pAuxDb->db = 0;
      }
    }else if( nArg==3 && cli_strcmp(azArg[1], "close")==0
           && IsDigit(azArg[2][0]) && azArg[2][1]==0 ){
      int i = azArg[2][0] - '0';
      if( i<0 || i>=ArraySize(p->aAuxDb) ){
        /* No-op */
      }else if( p->pAuxDb == &p->aAuxDb[i] ){
        raw_printf(stderr, "cannot close the active database connection\n");
        rc = 1;
      }else if( p->aAuxDb[i].db ){
        session_close_all(p, i);
        close_db(p->aAuxDb[i].db);
        p->aAuxDb[i].db = 0;
      }
    }else{
      raw_printf(stderr, "Usage: .connection [close] [CONNECTION-NUMBER]\n");
      rc = 1;
    }
  }else

  if( c=='d' && n>1 && cli_strncmp(azArg[0], "databases", n)==0 ){
    char **azName = 0;
    int nName = 0;
    sqlite3_stmt *pStmt;
    int i;
    open_db(p, 0);
    rc = sqlite3_prepare_v2(p->db, "PRAGMA database_list", -1, &pStmt, 0);
    if( rc ){

            eTxn==SQLITE_TXN_READ ? " read-txn" : " write-txn");
      free(azName[i*2]);
      free(azName[i*2+1]);
    }
    sqlite3_free(azName);
  }else

  if( c=='d' && n>=3 && cli_strncmp(azArg[0], "dbconfig", n)==0 ){
    static const struct DbConfigChoices {
      const char *zName;
      int op;
    } aDbConfig[] = {
        { "defensive",          SQLITE_DBCONFIG_DEFENSIVE             },
        { "dqs_ddl",            SQLITE_DBCONFIG_DQS_DDL               },
        { "dqs_dml",            SQLITE_DBCONFIG_DQS_DML               },

        { "trigger_eqp",        SQLITE_DBCONFIG_TRIGGER_EQP           },
        { "trusted_schema",     SQLITE_DBCONFIG_TRUSTED_SCHEMA        },
        { "writable_schema",    SQLITE_DBCONFIG_WRITABLE_SCHEMA       },
    };
    int ii, v;
    open_db(p, 0);
    for(ii=0; ii<ArraySize(aDbConfig); ii++){
      if( nArg>1 && cli_strcmp(azArg[1], aDbConfig[ii].zName)!=0 ) continue;
      if( nArg>=3 ){
        sqlite3_db_config(p->db, aDbConfig[ii].op, booleanValue(azArg[2]), 0);
      }
      sqlite3_db_config(p->db, aDbConfig[ii].op, -1, &v);
      utf8_printf(p->out, "%19s %s\n", aDbConfig[ii].zName, v ? "on" : "off");
      if( nArg>1 ) break;
    }
    if( nArg>1 && ii==ArraySize(aDbConfig) ){
      utf8_printf(stderr, "Error: unknown dbconfig \"%s\"\n", azArg[1]);
      utf8_printf(stderr, "Enter \".dbconfig\" with no arguments for a list\n");
    }   
  }else

#if SQLITE_SHELL_HAVE_RECOVER
  if( c=='d' && n>=3 && cli_strncmp(azArg[0], "dbinfo", n)==0 ){
    rc = shell_dbinfo_command(p, nArg, azArg);
  }else

  if( c=='r' && cli_strncmp(azArg[0], "recover", n)==0 ){
    open_db(p, 0);
    rc = recoverDatabaseCmd(p, nArg, azArg);
  }else
#endif /* SQLITE_SHELL_HAVE_RECOVER */

  if( c=='d' && cli_strncmp(azArg[0], "dump", n)==0 ){
    char *zLike = 0;
    char *zSql;
    int i;
    int savedShowHeader = p->showHeader;
    int savedShellFlags = p->shellFlgs;
    ShellClearFlag(p,
       SHFLG_PreserveRowid|SHFLG_Newlines|SHFLG_Echo
       |SHFLG_DumpDataOnly|SHFLG_DumpNoSys);
    for(i=1; i<nArg; i++){
      if( azArg[i][0]=='-' ){
        const char *z = azArg[i]+1;
        if( z[0]=='-' ) z++;
        if( cli_strcmp(z,"preserve-rowids")==0 ){
#ifdef SQLITE_OMIT_VIRTUALTABLE
          raw_printf(stderr, "The --preserve-rowids option is not compatible"
                             " with SQLITE_OMIT_VIRTUALTABLE\n");
          rc = 1;
          sqlite3_free(zLike);
          goto meta_command_exit;
#else
          ShellSetFlag(p, SHFLG_PreserveRowid);
#endif
        }else
        if( cli_strcmp(z,"newlines")==0 ){
          ShellSetFlag(p, SHFLG_Newlines);
        }else
        if( cli_strcmp(z,"data-only")==0 ){
          ShellSetFlag(p, SHFLG_DumpDataOnly);
        }else
        if( cli_strcmp(z,"nosys")==0 ){
          ShellSetFlag(p, SHFLG_DumpNoSys);
        }else
        {
          raw_printf(stderr, "Unknown option \"%s\" on \".dump\"\n", azArg[i]);
          rc = 1;
          sqlite3_free(zLike);
          goto meta_command_exit;

    if( (p->shellFlgs & SHFLG_DumpDataOnly)==0 ){
      raw_printf(p->out, p->nErr?"ROLLBACK; -- due to errors\n":"COMMIT;\n");
    }
    p->showHeader = savedShowHeader;
    p->shellFlgs = savedShellFlags;
  }else

  if( c=='e' && cli_strncmp(azArg[0], "echo", n)==0 ){
    if( nArg==2 ){
      setOrClearFlag(p, SHFLG_Echo, azArg[1]);
    }else{
      raw_printf(stderr, "Usage: .echo on|off\n");
      rc = 1;
    }
  }else

  if( c=='e' && cli_strncmp(azArg[0], "eqp", n)==0 ){
    if( nArg==2 ){
      p->autoEQPtest = 0;
      if( p->autoEQPtrace ){
        if( p->db ) sqlite3_exec(p->db, "PRAGMA vdbe_trace=OFF;", 0, 0, 0);
        p->autoEQPtrace = 0;
      }
      if( cli_strcmp(azArg[1],"full")==0 ){
        p->autoEQP = AUTOEQP_full;
      }else if( cli_strcmp(azArg[1],"trigger")==0 ){
        p->autoEQP = AUTOEQP_trigger;
#ifdef SQLITE_DEBUG
      }else if( cli_strcmp(azArg[1],"test")==0 ){
        p->autoEQP = AUTOEQP_on;
        p->autoEQPtest = 1;
      }else if( cli_strcmp(azArg[1],"trace")==0 ){
        p->autoEQP = AUTOEQP_full;
        p->autoEQPtrace = 1;
        open_db(p, 0);
        sqlite3_exec(p->db, "SELECT name FROM sqlite_schema LIMIT 1", 0, 0, 0);
        sqlite3_exec(p->db, "PRAGMA vdbe_trace=ON;", 0, 0, 0);
#endif
      }else{
        p->autoEQP = (u8)booleanValue(azArg[1]);
      }
    }else{
      raw_printf(stderr, "Usage: .eqp off|on|trace|trigger|full\n");
      rc = 1;
    }
  }else

#ifndef SQLITE_SHELL_FIDDLE
  if( c=='e' && cli_strncmp(azArg[0], "exit", n)==0 ){
    if( nArg>1 && (rc = (int)integerValue(azArg[1]))!=0 ) exit(rc);
    rc = 2;
  }else
#endif

  /* The ".explain" command is automatic now.  It is largely pointless.  It
  ** retained purely for backwards compatibility */
  if( c=='e' && cli_strncmp(azArg[0], "explain", n)==0 ){
    int val = 1;
    if( nArg>=2 ){
      if( cli_strcmp(azArg[1],"auto")==0 ){
        val = 99;
      }else{
        val =  booleanValue(azArg[1]);
      }
    }
    if( val==1 && p->mode!=MODE_Explain ){
      p->normalMode = p->mode;
      p->mode = MODE_Explain;
      p->autoExplain = 0;
    }else if( val==0 ){
      if( p->mode==MODE_Explain ) p->mode = p->normalMode;
      p->autoExplain = 0;
    }else if( val==99 ){
      if( p->mode==MODE_Explain ) p->mode = p->normalMode;
      p->autoExplain = 1;
    }
  }else

#ifndef SQLITE_OMIT_VIRTUALTABLE
  if( c=='e' && cli_strncmp(azArg[0], "expert", n)==0 ){
    if( p->bSafeMode ){
      raw_printf(stderr, 
        "Cannot run experimental commands such as \"%s\" in safe mode\n",
        azArg[0]);
      rc = 1;
    }else{
      open_db(p, 0);
      expertDotCommand(p, azArg, nArg);
    }
  }else
#endif

  if( c=='f' && cli_strncmp(azArg[0], "filectrl", n)==0 ){
    static const struct {
       const char *zCtrlName;   /* Name of a test-control option */
       int ctrlCode;            /* Integer code for that option */
       const char *zUsage;      /* Usage notes */
    } aCtrl[] = {
      { "chunk_size",     SQLITE_FCNTL_CHUNK_SIZE,      "SIZE"           },
      { "data_version",   SQLITE_FCNTL_DATA_VERSION,    ""               },

    const char *zCmd = 0;
    const char *zSchema = 0;

    open_db(p, 0);
    zCmd = nArg>=2 ? azArg[1] : "help";

    if( zCmd[0]=='-' 
     && (cli_strcmp(zCmd,"--schema")==0 || cli_strcmp(zCmd,"-schema")==0)
     && nArg>=4
    ){
      zSchema = azArg[2];
      for(i=3; i<nArg; i++) azArg[i-2] = azArg[i];
      nArg -= 2;
      zCmd = azArg[1];
    }

    /* The argument can optionally begin with "-" or "--" */
    if( zCmd[0]=='-' && zCmd[1] ){
      zCmd++;
      if( zCmd[0]=='-' && zCmd[1] ) zCmd++;
    }

    /* --help lists all file-controls */
    if( cli_strcmp(zCmd,"help")==0 ){
      utf8_printf(p->out, "Available file-controls:\n");
      for(i=0; i<ArraySize(aCtrl); i++){
        utf8_printf(p->out, "  .filectrl %s %s\n",
                    aCtrl[i].zCtrlName, aCtrl[i].zUsage);
      }
      rc = 1;
      goto meta_command_exit;
    }

    /* convert filectrl text option to value. allow any unique prefix
    ** of the option name, or a numerical value. */
    n2 = strlen30(zCmd);
    for(i=0; i<ArraySize(aCtrl); i++){
      if( cli_strncmp(zCmd, aCtrl[i].zCtrlName, n2)==0 ){
        if( filectrl<0 ){
          filectrl = aCtrl[i].ctrlCode;
          iCtrl = i;
        }else{
          utf8_printf(stderr, "Error: ambiguous file-control: \"%s\"\n"
                              "Use \".filectrl --help\" for help\n", zCmd);
          rc = 1;

    }else if( isOk==1 ){
      char zBuf[100];
      sqlite3_snprintf(sizeof(zBuf), zBuf, "%lld", iRes);
      raw_printf(p->out, "%s\n", zBuf);
    }
  }else

  if( c=='f' && cli_strncmp(azArg[0], "fullschema", n)==0 ){
    ShellState data;
    int doStats = 0;
    memcpy(&data, p, sizeof(data));
    data.showHeader = 0;
    data.cMode = data.mode = MODE_Semi;
    if( nArg==2 && optionMatch(azArg[1], "indent") ){
      data.cMode = data.mode = MODE_Pretty;

      shell_exec(&data, "SELECT * FROM sqlite_stat1", 0);
      data.zDestTable = "sqlite_stat4";
      shell_exec(&data, "SELECT * FROM sqlite_stat4", 0);
      raw_printf(p->out, "ANALYZE sqlite_schema;\n");
    }
  }else

  if( c=='h' && cli_strncmp(azArg[0], "headers", n)==0 ){
    if( nArg==2 ){
      p->showHeader = booleanValue(azArg[1]);
      p->shellFlgs |= SHFLG_HeaderSet;
    }else{
      raw_printf(stderr, "Usage: .headers on|off\n");
      rc = 1;
    }
  }else

  if( c=='h' && cli_strncmp(azArg[0], "help", n)==0 ){
    if( nArg>=2 ){
      n = showHelp(p->out, azArg[1]);
      if( n==0 ){
        utf8_printf(p->out, "Nothing matches '%s'\n", azArg[1]);
      }
    }else{
      showHelp(p->out, 0);
    }
  }else

#ifndef SQLITE_SHELL_FIDDLE
  if( c=='i' && cli_strncmp(azArg[0], "import", n)==0 ){
    char *zTable = 0;           /* Insert data into this table */
    char *zSchema = 0;          /* within this schema (may default to "main") */
    char *zFile = 0;            /* Name of file to extra content from */
    sqlite3_stmt *pStmt = NULL; /* A statement */
    int nCol;                   /* Number of columns in the table */
    int nByte;                  /* Number of bytes in an SQL string */
    int i, j;                   /* Loop counters */

        }else if( zTable==0 ){
          zTable = z;
        }else{
          utf8_printf(p->out, "ERROR: extra argument: \"%s\".  Usage:\n", z);
          showHelp(p->out, "import");
          goto meta_command_exit;
        }
      }else if( cli_strcmp(z,"-v")==0 ){
        eVerbose++;
      }else if( cli_strcmp(z,"-schema")==0 && i<nArg-1 ){
        zSchema = azArg[++i];
      }else if( cli_strcmp(z,"-skip")==0 && i<nArg-1 ){
        nSkip = integerValue(azArg[++i]);
      }else if( cli_strcmp(z,"-ascii")==0 ){
        sCtx.cColSep = SEP_Unit[0];
        sCtx.cRowSep = SEP_Record[0];
        xRead = ascii_read_one_field;
        useOutputMode = 0;
      }else if( cli_strcmp(z,"-csv")==0 ){
        sCtx.cColSep = ',';
        sCtx.cRowSep = '\n';
        xRead = csv_read_one_field;
        useOutputMode = 0;
      }else{
        utf8_printf(p->out, "ERROR: unknown option: \"%s\".  Usage:\n", z);
        showHelp(p->out, "import");

      }
      nSep = strlen30(p->rowSeparator);
      if( nSep==0 ){
        raw_printf(stderr,
            "Error: non-null row separator required for import\n");
        goto meta_command_exit;
      }
      if( nSep==2 && p->mode==MODE_Csv
       && cli_strcmp(p->rowSeparator,SEP_CrLf)==0
      ){
        /* When importing CSV (only), if the row separator is set to the
        ** default output row separator, change it to the default input
        ** row separator.  This avoids having to maintain different input
        ** and output row separators. */
        sqlite3_snprintf(sizeof(p->rowSeparator), p->rowSeparator, SEP_Row);
        nSep = strlen30(p->rowSeparator);
      }

    if( needCommit ) sqlite3_exec(p->db, "COMMIT", 0, 0, 0);
    if( eVerbose>0 ){
      utf8_printf(p->out,
          "Added %d rows with %d errors using %d lines of input\n",
          sCtx.nRow, sCtx.nErr, sCtx.nLine-1);
    }
  }else
#endif /* !defined(SQLITE_SHELL_FIDDLE) */

#ifndef SQLITE_UNTESTABLE
  if( c=='i' && cli_strncmp(azArg[0], "imposter", n)==0 ){
    char *zSql;
    char *zCollist = 0;
    sqlite3_stmt *pStmt;
    int tnum = 0;
    int isWO = 0;  /* True if making an imposter of a WITHOUT ROWID table */
    int lenPK = 0; /* Length of the PRIMARY KEY string for isWO tables */
    int i;

      rc = 1;
    }
    sqlite3_free(zSql);
  }else
#endif /* !defined(SQLITE_OMIT_TEST_CONTROL) */

#ifdef SQLITE_ENABLE_IOTRACE
  if( c=='i' && cli_strncmp(azArg[0], "iotrace", n)==0 ){
    SQLITE_API extern void (SQLITE_CDECL *sqlite3IoTrace)(const char*, ...);
    if( iotrace && iotrace!=stdout ) fclose(iotrace);
    iotrace = 0;
    if( nArg<2 ){
      sqlite3IoTrace = 0;
    }else if( cli_strcmp(azArg[1], "-")==0 ){
      sqlite3IoTrace = iotracePrintf;
      iotrace = stdout;
    }else{
      iotrace = fopen(azArg[1], "w");
      if( iotrace==0 ){
        utf8_printf(stderr, "Error: cannot open \"%s\"\n", azArg[1]);
        sqlite3IoTrace = 0;
        rc = 1;
      }else{
        sqlite3IoTrace = iotracePrintf;
      }
    }
  }else
#endif

  if( c=='l' && n>=5 && cli_strncmp(azArg[0], "limits", n)==0 ){
    static const struct {
       const char *zLimitName;   /* Name of a limit */
       int limitCode;            /* Integer code for that limit */
    } aLimit[] = {
      { "length",                SQLITE_LIMIT_LENGTH                    },
      { "sql_length",            SQLITE_LIMIT_SQL_LENGTH                },
      { "column",                SQLITE_LIMIT_COLUMN                    },

                      (int)integerValue(azArg[2]));
      }
      printf("%20s %d\n", aLimit[iLimit].zLimitName,
             sqlite3_limit(p->db, aLimit[iLimit].limitCode, -1));
    }
  }else

  if( c=='l' && n>2 && cli_strncmp(azArg[0], "lint", n)==0 ){
    open_db(p, 0);
    lintDotCommand(p, azArg, nArg);
  }else

#if !defined(SQLITE_OMIT_LOAD_EXTENSION) && !defined(SQLITE_SHELL_FIDDLE)
  if( c=='l' && cli_strncmp(azArg[0], "load", n)==0 ){
    const char *zFile, *zProc;
    char *zErrMsg = 0;
    failIfSafeMode(p, "cannot run .load in safe mode");
    if( nArg<2 ){
      raw_printf(stderr, "Usage: .load FILE ?ENTRYPOINT?\n");
      rc = 1;
      goto meta_command_exit;
    }
    zFile = azArg[1];
    zProc = nArg>=3 ? azArg[2] : 0;
    open_db(p, 0);
    rc = sqlite3_load_extension(p->db, zFile, zProc, &zErrMsg);
    if( rc!=SQLITE_OK ){
      utf8_printf(stderr, "Error: %s\n", zErrMsg);
      sqlite3_free(zErrMsg);
      rc = 1;
    }
  }else
#endif

#ifndef SQLITE_SHELL_FIDDLE
  if( c=='l' && cli_strncmp(azArg[0], "log", n)==0 ){
    failIfSafeMode(p, "cannot run .log in safe mode");
    if( nArg!=2 ){
      raw_printf(stderr, "Usage: .log FILENAME\n");
      rc = 1;
    }else{
      const char *zFile = azArg[1];
      output_file_close(p->pLog);
      p->pLog = output_file_open(zFile, 0);
    }
  }else
#endif

  if( c=='m' && cli_strncmp(azArg[0], "mode", n)==0 ){
    const char *zMode = 0;
    const char *zTabname = 0;
    int i, n2;
    ColModeOpts cmOpts = ColModeOpts_default;
    for(i=1; i<nArg; i++){
      const char *z = azArg[i];
      if( optionMatch(z,"wrap") && i+1<nArg ){
        cmOpts.iWrap = integerValue(azArg[++i]);
      }else if( optionMatch(z,"ww") ){
        cmOpts.bWordWrap = 1;
      }else if( optionMatch(z,"wordwrap") && i+1<nArg ){
        cmOpts.bWordWrap = (u8)booleanValue(azArg[++i]);
      }else if( optionMatch(z,"quote") ){
        cmOpts.bQuote = 1;
      }else if( optionMatch(z,"noquote") ){
        cmOpts.bQuote = 0;
      }else if( zMode==0 ){
        zMode = z;
        /* Apply defaults for qbox pseudo-mode.  If that
         * overwrites already-set values, user was informed of this.
         */
        if( cli_strcmp(z, "qbox")==0 ){
          ColModeOpts cmo = ColModeOpts_default_qbox;
          zMode = "box";
          cmOpts = cmo;
        }
      }else if( zTabname==0 ){
        zTabname = z;
      }else if( z[0]=='-' ){

           p->cmOpts.bQuote ? "" : "no");
      }else{
        raw_printf(p->out, "current output mode: %s\n", modeDescr[p->mode]);
      }
      zMode = modeDescr[p->mode];
    }
    n2 = strlen30(zMode);
    if( cli_strncmp(zMode,"lines",n2)==0 ){
      p->mode = MODE_Line;
      sqlite3_snprintf(sizeof(p->rowSeparator), p->rowSeparator, SEP_Row);
    }else if( cli_strncmp(zMode,"columns",n2)==0 ){
      p->mode = MODE_Column;
      if( (p->shellFlgs & SHFLG_HeaderSet)==0 ){
        p->showHeader = 1;
      }
      sqlite3_snprintf(sizeof(p->rowSeparator), p->rowSeparator, SEP_Row);
      p->cmOpts = cmOpts;
    }else if( cli_strncmp(zMode,"list",n2)==0 ){
      p->mode = MODE_List;
      sqlite3_snprintf(sizeof(p->colSeparator), p->colSeparator, SEP_Column);
      sqlite3_snprintf(sizeof(p->rowSeparator), p->rowSeparator, SEP_Row);
    }else if( cli_strncmp(zMode,"html",n2)==0 ){
      p->mode = MODE_Html;
    }else if( cli_strncmp(zMode,"tcl",n2)==0 ){
      p->mode = MODE_Tcl;
      sqlite3_snprintf(sizeof(p->colSeparator), p->colSeparator, SEP_Space);
      sqlite3_snprintf(sizeof(p->rowSeparator), p->rowSeparator, SEP_Row);
    }else if( cli_strncmp(zMode,"csv",n2)==0 ){
      p->mode = MODE_Csv;
      sqlite3_snprintf(sizeof(p->colSeparator), p->colSeparator, SEP_Comma);
      sqlite3_snprintf(sizeof(p->rowSeparator), p->rowSeparator, SEP_CrLf);
    }else if( cli_strncmp(zMode,"tabs",n2)==0 ){
      p->mode = MODE_List;
      sqlite3_snprintf(sizeof(p->colSeparator), p->colSeparator, SEP_Tab);
    }else if( cli_strncmp(zMode,"insert",n2)==0 ){
      p->mode = MODE_Insert;
      set_table_name(p, zTabname ? zTabname : "table");
    }else if( cli_strncmp(zMode,"quote",n2)==0 ){
      p->mode = MODE_Quote;
      sqlite3_snprintf(sizeof(p->colSeparator), p->colSeparator, SEP_Comma);
      sqlite3_snprintf(sizeof(p->rowSeparator), p->rowSeparator, SEP_Row);
    }else if( cli_strncmp(zMode,"ascii",n2)==0 ){
      p->mode = MODE_Ascii;
      sqlite3_snprintf(sizeof(p->colSeparator), p->colSeparator, SEP_Unit);
      sqlite3_snprintf(sizeof(p->rowSeparator), p->rowSeparator, SEP_Record);
    }else if( cli_strncmp(zMode,"markdown",n2)==0 ){
      p->mode = MODE_Markdown;
      p->cmOpts = cmOpts;
    }else if( cli_strncmp(zMode,"table",n2)==0 ){
      p->mode = MODE_Table;
      p->cmOpts = cmOpts;
    }else if( cli_strncmp(zMode,"box",n2)==0 ){
      p->mode = MODE_Box;
      p->cmOpts = cmOpts;
    }else if( cli_strncmp(zMode,"count",n2)==0 ){
      p->mode = MODE_Count;
    }else if( cli_strncmp(zMode,"off",n2)==0 ){
      p->mode = MODE_Off;
    }else if( cli_strncmp(zMode,"json",n2)==0 ){
      p->mode = MODE_Json;
    }else{
      raw_printf(stderr, "Error: mode should be one of: "
         "ascii box column csv html insert json line list markdown "
         "qbox quote table tabs tcl\n");
      rc = 1;
    }
    p->cMode = p->mode;
  }else

#ifndef SQLITE_SHELL_FIDDLE
  if( c=='n' && cli_strcmp(azArg[0], "nonce")==0 ){
    if( nArg!=2 ){
      raw_printf(stderr, "Usage: .nonce NONCE\n");
      rc = 1;
    }else if( p->zNonce==0 || cli_strcmp(azArg[1],p->zNonce)!=0 ){
      raw_printf(stderr, "line %d: incorrect nonce: \"%s\"\n",
                 p->lineno, azArg[1]);
      exit(1);
    }else{
      p->bSafeMode = 0;
      return 0;  /* Return immediately to bypass the safe mode reset
                 ** at the end of this procedure */
    }
  }else
#endif /* !defined(SQLITE_SHELL_FIDDLE) */

  if( c=='n' && cli_strncmp(azArg[0], "nullvalue", n)==0 ){
    if( nArg==2 ){
      sqlite3_snprintf(sizeof(p->nullValue), p->nullValue,
                       "%.*s", (int)ArraySize(p->nullValue)-1, azArg[1]);
    }else{
      raw_printf(stderr, "Usage: .nullvalue STRING\n");
      rc = 1;
    }
  }else

  if( c=='o' && cli_strncmp(azArg[0], "open", n)==0 && n>=2 ){
    const char *zFN = 0;     /* Pointer to constant filename */
    char *zNewFilename = 0;  /* Name of the database file to open */
    int iName = 1;           /* Index in azArg[] of the filename */
    int newFlag = 0;         /* True to delete file before opening */
    int openMode = SHELL_OPEN_UNSPEC;

    /* Check for command-line arguments */
    for(iName=1; iName<nArg; iName++){
      const char *z = azArg[iName];
#ifndef SQLITE_SHELL_FIDDLE
      if( optionMatch(z,"new") ){
        newFlag = 1;
#ifdef SQLITE_HAVE_ZLIB
      }else if( optionMatch(z, "zip") ){
        openMode = SHELL_OPEN_ZIPFILE;
#endif
      }else if( optionMatch(z, "append") ){

        openMode = SHELL_OPEN_DESERIALIZE;
      }else if( optionMatch(z, "hexdb") ){
        openMode = SHELL_OPEN_HEXDB;
      }else if( optionMatch(z, "maxsize") && iName+1<nArg ){
        p->szMax = integerValue(azArg[++iName]);
#endif /* SQLITE_OMIT_DESERIALIZE */
      }else
#endif /* !SQLITE_SHELL_FIDDLE */
      if( z[0]=='-' ){
        utf8_printf(stderr, "unknown option: %s\n", z);
        rc = 1;
        goto meta_command_exit;
      }else if( zFN ){
        utf8_printf(stderr, "extra argument: \"%s\"\n", z);
        rc = 1;

    p->openMode = openMode;
    p->openFlags = 0;
    p->szMax = 0;

    /* If a filename is specified, try to open it first */
    if( zFN || p->openMode==SHELL_OPEN_HEXDB ){
      if( newFlag && zFN && !p->bSafeMode ) shellDeleteFile(zFN);
#ifndef SQLITE_SHELL_FIDDLE
      if( p->bSafeMode
       && p->openMode!=SHELL_OPEN_HEXDB
       && zFN
       && cli_strcmp(zFN,":memory:")!=0
      ){
        failIfSafeMode(p, "cannot open disk-based database files in safe mode");
      }
#else
      /* WASM mode has its own sandboxed pseudo-filesystem. */
#endif
      if( zFN ){

    if( p->db==0 ){
      /* As a fall-back open a TEMP database */
      p->pAuxDb->zDbFilename = 0;
      open_db(p, 0);
    }
  }else

#ifndef SQLITE_SHELL_FIDDLE
  if( (c=='o'
        && (cli_strncmp(azArg[0], "output", n)==0
            || cli_strncmp(azArg[0], "once", n)==0))
   || (c=='e' && n==5 && cli_strcmp(azArg[0],"excel")==0)
  ){
    char *zFile = 0;
    int bTxtMode = 0;
    int i;
    int eMode = 0;
    int bOnce = 0;            /* 0: .output, 1: .once, 2: .excel */
    unsigned char zBOM[4];    /* Byte-order mark to using if --bom is present */

    zBOM[0] = 0;
    failIfSafeMode(p, "cannot run .%s in safe mode", azArg[0]);
    if( c=='e' ){
      eMode = 'x';
      bOnce = 2;
    }else if( cli_strncmp(azArg[0],"once",n)==0 ){
      bOnce = 1;
    }
    for(i=1; i<nArg; i++){
      char *z = azArg[i];
      if( z[0]=='-' ){
        if( z[1]=='-' ) z++;
        if( cli_strcmp(z,"-bom")==0 ){
          zBOM[0] = 0xef;
          zBOM[1] = 0xbb;
          zBOM[2] = 0xbf;
          zBOM[3] = 0;
        }else if( c!='e' && cli_strcmp(z,"-x")==0 ){
          eMode = 'x';  /* spreadsheet */
        }else if( c!='e' && cli_strcmp(z,"-e")==0 ){
          eMode = 'e';  /* text editor */
        }else{
          utf8_printf(p->out, "ERROR: unknown option: \"%s\".  Usage:\n",
                      azArg[i]);
          showHelp(p->out, azArg[0]);
          rc = 1;
          goto meta_command_exit;

        if( zBOM[0] ) fwrite(zBOM, 1, 3, p->out);
        sqlite3_snprintf(sizeof(p->outfile), p->outfile, "%s", zFile);
      }
#endif
    }else{
      p->out = output_file_open(zFile, bTxtMode);
      if( p->out==0 ){
        if( cli_strcmp(zFile,"off")!=0 ){
          utf8_printf(stderr,"Error: cannot write to \"%s\"\n", zFile);
        }
        p->out = stdout;
        rc = 1;
      } else {
        if( zBOM[0] ) fwrite(zBOM, 1, 3, p->out);
        sqlite3_snprintf(sizeof(p->outfile), p->outfile, "%s", zFile);
      }
    }
    sqlite3_free(zFile);
  }else
#endif /* !defined(SQLITE_SHELL_FIDDLE) */

  if( c=='p' && n>=3 && cli_strncmp(azArg[0], "parameter", n)==0 ){
    open_db(p,0);
    if( nArg<=1 ) goto parameter_syntax_error;

    /* .parameter clear
    ** Clear all bind parameters by dropping the TEMP table that holds them.
    */
    if( nArg==2 && cli_strcmp(azArg[1],"clear")==0 ){
      sqlite3_exec(p->db, "DROP TABLE IF EXISTS temp.sqlite_parameters;",
                   0, 0, 0);
    }else

    /* .parameter list
    ** List all bind parameters.
    */
    if( nArg==2 && cli_strcmp(azArg[1],"list")==0 ){
      sqlite3_stmt *pStmt = 0;
      int rx;
      int len = 0;
      rx = sqlite3_prepare_v2(p->db,
             "SELECT max(length(key)) "
             "FROM temp.sqlite_parameters;", -1, &pStmt, 0);
      if( rx==SQLITE_OK && sqlite3_step(pStmt)==SQLITE_ROW ){

      }
    }else

    /* .parameter init
    ** Make sure the TEMP table used to hold bind parameters exists.
    ** Create it if necessary.
    */
    if( nArg==2 && cli_strcmp(azArg[1],"init")==0 ){
      bind_table_init(p);
    }else

    /* .parameter set NAME VALUE
    ** Set or reset a bind parameter.  NAME should be the full parameter
    ** name exactly as it appears in the query.  (ex: $abc, @def).  The
    ** VALUE can be in either SQL literal notation, or if not it will be
    ** understood to be a text string.
    */
    if( nArg==4 && cli_strcmp(azArg[1],"set")==0 ){
      int rx;
      char *zSql;
      sqlite3_stmt *pStmt;
      const char *zKey = azArg[2];
      const char *zValue = azArg[3];
      bind_table_init(p);
      zSql = sqlite3_mprintf(

      sqlite3_finalize(pStmt);
    }else

    /* .parameter unset NAME
    ** Remove the NAME binding from the parameter binding table, if it
    ** exists.
    */
    if( nArg==3 && cli_strcmp(azArg[1],"unset")==0 ){
      char *zSql = sqlite3_mprintf(
          "DELETE FROM temp.sqlite_parameters WHERE key=%Q", azArg[2]);
      shell_check_oom(zSql);
      sqlite3_exec(p->db, zSql, 0, 0, 0);
      sqlite3_free(zSql);
    }else
    /* If no command name matches, show a syntax error */
    parameter_syntax_error:
    showHelp(p->out, "parameter");
  }else

  if( c=='p' && n>=3 && cli_strncmp(azArg[0], "print", n)==0 ){
    int i;
    for(i=1; i<nArg; i++){
      if( i>1 ) raw_printf(p->out, " ");
      utf8_printf(p->out, "%s", azArg[i]);
    }
    raw_printf(p->out, "\n");
  }else

#ifndef SQLITE_OMIT_PROGRESS_CALLBACK
  if( c=='p' && n>=3 && cli_strncmp(azArg[0], "progress", n)==0 ){
    int i;
    int nn = 0;
    p->flgProgress = 0;
    p->mxProgress = 0;
    p->nProgress = 0;
    for(i=1; i<nArg; i++){
      const char *z = azArg[i];
      if( z[0]=='-' ){
        z++;
        if( z[0]=='-' ) z++;
        if( cli_strcmp(z,"quiet")==0 || cli_strcmp(z,"q")==0 ){
          p->flgProgress |= SHELL_PROGRESS_QUIET;
          continue;
        }
        if( cli_strcmp(z,"reset")==0 ){
          p->flgProgress |= SHELL_PROGRESS_RESET;
          continue;
        }
        if( cli_strcmp(z,"once")==0 ){
          p->flgProgress |= SHELL_PROGRESS_ONCE;
          continue;
        }
        if( cli_strcmp(z,"limit")==0 ){
          if( i+1>=nArg ){
            utf8_printf(stderr, "Error: missing argument on --limit\n");
            rc = 1;
            goto meta_command_exit;
          }else{
            p->mxProgress = (int)integerValue(azArg[++i]);
          }

      }
    }
    open_db(p, 0);
    sqlite3_progress_handler(p->db, nn, progress_handler, p);
  }else
#endif /* SQLITE_OMIT_PROGRESS_CALLBACK */

  if( c=='p' && cli_strncmp(azArg[0], "prompt", n)==0 ){
    if( nArg >= 2) {
      strncpy(mainPrompt,azArg[1],(int)ArraySize(mainPrompt)-1);
    }
    if( nArg >= 3) {
      strncpy(continuePrompt,azArg[2],(int)ArraySize(continuePrompt)-1);
    }
  }else

#ifndef SQLITE_SHELL_FIDDLE
  if( c=='q' && cli_strncmp(azArg[0], "quit", n)==0 ){
    rc = 2;
  }else
#endif

#ifndef SQLITE_SHELL_FIDDLE
  if( c=='r' && n>=3 && cli_strncmp(azArg[0], "read", n)==0 ){
    FILE *inSaved = p->in;
    int savedLineno = p->lineno;
    failIfSafeMode(p, "cannot run .read in safe mode");
    if( nArg!=2 ){
      raw_printf(stderr, "Usage: .read FILE\n");
      rc = 1;
      goto meta_command_exit;

    }else{
      rc = process_input(p);
      fclose(p->in);
    }
    p->in = inSaved;
    p->lineno = savedLineno;
  }else
#endif /* !defined(SQLITE_SHELL_FIDDLE) */

#ifndef SQLITE_SHELL_FIDDLE
  if( c=='r' && n>=3 && cli_strncmp(azArg[0], "restore", n)==0 ){
    const char *zSrcFile;
    const char *zDb;
    sqlite3 *pSrc;
    sqlite3_backup *pBackup;
    int nTimeout = 0;

    failIfSafeMode(p, "cannot run .restore in safe mode");

      rc = 1;
    }else{
      utf8_printf(stderr, "Error: %s\n", sqlite3_errmsg(p->db));
      rc = 1;
    }
    close_db(pSrc);
  }else
#endif /* !defined(SQLITE_SHELL_FIDDLE) */

  if( c=='s' && cli_strncmp(azArg[0], "scanstats", n)==0 ){
    if( nArg==2 ){
      p->scanstatsOn = (u8)booleanValue(azArg[1]);
#ifndef SQLITE_ENABLE_STMT_SCANSTATUS
      raw_printf(stderr, "Warning: .scanstats not available in this build.\n");
#endif
    }else{
      raw_printf(stderr, "Usage: .scanstats on|off\n");
      rc = 1;
    }
  }else

  if( c=='s' && cli_strncmp(azArg[0], "schema", n)==0 ){
    ShellText sSelect;
    ShellState data;
    char *zErrMsg = 0;
    const char *zDiv = "(";
    const char *zName = 0;
    int iSchema = 0;
    int bDebug = 0;

      raw_printf(stderr,"Error: querying schema information\n");
      rc = 1;
    }else{
      rc = 0;
    }
  }else

  if( (c=='s' && n==11 && cli_strncmp(azArg[0], "selecttrace", n)==0)
   || (c=='t' && n==9  && cli_strncmp(azArg[0], "treetrace", n)==0)
  ){
    unsigned int x = nArg>=2 ? (unsigned int)integerValue(azArg[1]) : 0xffffffff;
    sqlite3_test_control(SQLITE_TESTCTRL_TRACEFLAGS, 1, &x);
  }else

#if defined(SQLITE_ENABLE_SESSION)
  if( c=='s' && cli_strncmp(azArg[0],"session",n)==0 && n>=3 ){
    struct AuxDb *pAuxDb = p->pAuxDb;
    OpenSession *pSession = &pAuxDb->aSession[0];
    char **azCmd = &azArg[1];
    int iSes = 0;
    int nCmd = nArg - 1;
    int i;
    if( nArg<=1 ) goto session_syntax_error;
    open_db(p, 0);
    if( nArg>=3 ){
      for(iSes=0; iSes<pAuxDb->nSession; iSes++){
        if( cli_strcmp(pAuxDb->aSession[iSes].zName, azArg[1])==0 ) break;
      }
      if( iSes<pAuxDb->nSession ){
        pSession = &pAuxDb->aSession[iSes];
        azCmd++;
        nCmd--;
      }else{
        pSession = &pAuxDb->aSession[0];
        iSes = 0;
      }
    }

    /* .session attach TABLE
    ** Invoke the sqlite3session_attach() interface to attach a particular
    ** table so that it is never filtered.
    */
    if( cli_strcmp(azCmd[0],"attach")==0 ){
      if( nCmd!=2 ) goto session_syntax_error;
      if( pSession->p==0 ){
        session_not_open:
        raw_printf(stderr, "ERROR: No sessions are open\n");
      }else{
        rc = sqlite3session_attach(pSession->p, azCmd[1]);
        if( rc ){
          raw_printf(stderr, "ERROR: sqlite3session_attach() returns %d\n", rc);
          rc = 0;
        }
      }
    }else

    /* .session changeset FILE
    ** .session patchset FILE
    ** Write a changeset or patchset into a file.  The file is overwritten.
    */
    if( cli_strcmp(azCmd[0],"changeset")==0
     || cli_strcmp(azCmd[0],"patchset")==0
    ){
      FILE *out = 0;
      failIfSafeMode(p, "cannot run \".session %s\" in safe mode", azCmd[0]);
      if( nCmd!=2 ) goto session_syntax_error;
      if( pSession->p==0 ) goto session_not_open;
      out = fopen(azCmd[1], "wb");
      if( out==0 ){
        utf8_printf(stderr, "ERROR: cannot open \"%s\" for writing\n",

        fclose(out);
      }
    }else

    /* .session close
    ** Close the identified session
    */
    if( cli_strcmp(azCmd[0], "close")==0 ){
      if( nCmd!=1 ) goto session_syntax_error;
      if( pAuxDb->nSession ){
        session_close(pSession);
        pAuxDb->aSession[iSes] = pAuxDb->aSession[--pAuxDb->nSession];
      }
    }else

    /* .session enable ?BOOLEAN?
    ** Query or set the enable flag
    */
    if( cli_strcmp(azCmd[0], "enable")==0 ){
      int ii;
      if( nCmd>2 ) goto session_syntax_error;
      ii = nCmd==1 ? -1 : booleanValue(azCmd[1]);
      if( pAuxDb->nSession ){
        ii = sqlite3session_enable(pSession->p, ii);
        utf8_printf(p->out, "session %s enable flag = %d\n",
                    pSession->zName, ii);
      }
    }else

    /* .session filter GLOB ....
    ** Set a list of GLOB patterns of table names to be excluded.
    */
    if( cli_strcmp(azCmd[0], "filter")==0 ){
      int ii, nByte;
      if( nCmd<2 ) goto session_syntax_error;
      if( pAuxDb->nSession ){
        for(ii=0; ii<pSession->nFilter; ii++){
          sqlite3_free(pSession->azFilter[ii]);
        }
        sqlite3_free(pSession->azFilter);

        pSession->nFilter = ii-1;
      }
    }else

    /* .session indirect ?BOOLEAN?
    ** Query or set the indirect flag
    */
    if( cli_strcmp(azCmd[0], "indirect")==0 ){
      int ii;
      if( nCmd>2 ) goto session_syntax_error;
      ii = nCmd==1 ? -1 : booleanValue(azCmd[1]);
      if( pAuxDb->nSession ){
        ii = sqlite3session_indirect(pSession->p, ii);
        utf8_printf(p->out, "session %s indirect flag = %d\n",
                    pSession->zName, ii);
      }
    }else

    /* .session isempty
    ** Determine if the session is empty
    */
    if( cli_strcmp(azCmd[0], "isempty")==0 ){
      int ii;
      if( nCmd!=1 ) goto session_syntax_error;
      if( pAuxDb->nSession ){
        ii = sqlite3session_isempty(pSession->p);
        utf8_printf(p->out, "session %s isempty flag = %d\n",
                    pSession->zName, ii);
      }
    }else

    /* .session list
    ** List all currently open sessions
    */
    if( cli_strcmp(azCmd[0],"list")==0 ){
      for(i=0; i<pAuxDb->nSession; i++){
        utf8_printf(p->out, "%d %s\n", i, pAuxDb->aSession[i].zName);
      }
    }else

    /* .session open DB NAME
    ** Open a new session called NAME on the attached database DB.
    ** DB is normally "main".
    */
    if( cli_strcmp(azCmd[0],"open")==0 ){
      char *zName;
      if( nCmd!=3 ) goto session_syntax_error;
      zName = azCmd[2];
      if( zName[0]==0 ) goto session_syntax_error;
      for(i=0; i<pAuxDb->nSession; i++){
        if( cli_strcmp(pAuxDb->aSession[i].zName,zName)==0 ){
          utf8_printf(stderr, "Session \"%s\" already exists\n", zName);
          goto meta_command_exit;
        }
      }
      if( pAuxDb->nSession>=ArraySize(pAuxDb->aSession) ){
        raw_printf(stderr, "Maximum of %d sessions\n", ArraySize(pAuxDb->aSession));
        goto meta_command_exit;

    showHelp(p->out, "session");
  }else
#endif

#ifdef SQLITE_DEBUG
  /* Undocumented commands for internal testing.  Subject to change
  ** without notice. */
  if( c=='s' && n>=10 && cli_strncmp(azArg[0], "selftest-", 9)==0 ){
    if( cli_strncmp(azArg[0]+9, "boolean", n-9)==0 ){
      int i, v;
      for(i=1; i<nArg; i++){
        v = booleanValue(azArg[i]);
        utf8_printf(p->out, "%s: %d 0x%x\n", azArg[i], v, v);
      }
    }
    if( cli_strncmp(azArg[0]+9, "integer", n-9)==0 ){
      int i; sqlite3_int64 v;
      for(i=1; i<nArg; i++){
        char zBuf[200];
        v = integerValue(azArg[i]);
        sqlite3_snprintf(sizeof(zBuf),zBuf,"%s: %lld 0x%llx\n", azArg[i],v,v);
        utf8_printf(p->out, "%s", zBuf);
      }
    }
  }else
#endif

  if( c=='s' && n>=4 && cli_strncmp(azArg[0],"selftest",n)==0 ){
    int bIsInit = 0;         /* True to initialize the SELFTEST table */
    int bVerbose = 0;        /* Verbose output */
    int bSelftestExists;     /* True if SELFTEST already exists */
    int i, k;                /* Loop counters */
    int nTest = 0;           /* Number of tests runs */
    int nErr = 0;            /* Number of errors seen */
    ShellText str;           /* Answer for a query */
    sqlite3_stmt *pStmt = 0; /* Query against the SELFTEST table */

    open_db(p,0);
    for(i=1; i<nArg; i++){
      const char *z = azArg[i];
      if( z[0]=='-' && z[1]=='-' ) z++;
      if( cli_strcmp(z,"-init")==0 ){
        bIsInit = 1;
      }else
      if( cli_strcmp(z,"-v")==0 ){
        bVerbose++;
      }else
      {
        utf8_printf(stderr, "Unknown option \"%s\" on \"%s\"\n",
                    azArg[i], azArg[0]);
        raw_printf(stderr, "Should be one of: --init -v\n");
        rc = 1;

        if( zOp==0 ) continue;
        if( zSql==0 ) continue;
        if( zAns==0 ) continue;
        k = 0;
        if( bVerbose>0 ){
          printf("%d: %s %s\n", tno, zOp, zSql);
        }
        if( cli_strcmp(zOp,"memo")==0 ){
          utf8_printf(p->out, "%s\n", zSql);
        }else
        if( cli_strcmp(zOp,"run")==0 ){
          char *zErrMsg = 0;
          str.n = 0;
          str.z[0] = 0;
          rc = sqlite3_exec(p->db, zSql, captureOutputCallback, &str, &zErrMsg);
          nTest++;
          if( bVerbose ){
            utf8_printf(p->out, "Result: %s\n", str.z);
          }
          if( rc || zErrMsg ){
            nErr++;
            rc = 1;
            utf8_printf(p->out, "%d: error-code-%d: %s\n", tno, rc, zErrMsg);
            sqlite3_free(zErrMsg);
          }else if( cli_strcmp(zAns,str.z)!=0 ){
            nErr++;
            rc = 1;
            utf8_printf(p->out, "%d: Expected: [%s]\n", tno, zAns);
            utf8_printf(p->out, "%d:      Got: [%s]\n", tno, str.z);
          }
        }else
        {
          utf8_printf(stderr,
            "Unknown operation \"%s\" on selftest line %d\n", zOp, tno);
          rc = 1;
          break;
        }
      } /* End loop over rows of content from SELFTEST */
      sqlite3_finalize(pStmt);
    } /* End loop over k */
    freeText(&str);
    utf8_printf(p->out, "%d errors out of %d tests\n", nErr, nTest);
  }else

  if( c=='s' && cli_strncmp(azArg[0], "separator", n)==0 ){
    if( nArg<2 || nArg>3 ){
      raw_printf(stderr, "Usage: .separator COL ?ROW?\n");
      rc = 1;
    }
    if( nArg>=2 ){
      sqlite3_snprintf(sizeof(p->colSeparator), p->colSeparator,
                       "%.*s", (int)ArraySize(p->colSeparator)-1, azArg[1]);
    }
    if( nArg>=3 ){
      sqlite3_snprintf(sizeof(p->rowSeparator), p->rowSeparator,
                       "%.*s", (int)ArraySize(p->rowSeparator)-1, azArg[2]);
    }
  }else

  if( c=='s' && n>=4 && cli_strncmp(azArg[0],"sha3sum",n)==0 ){
    const char *zLike = 0;   /* Which table to checksum. 0 means everything */
    int i;                   /* Loop counter */
    int bSchema = 0;         /* Also hash the schema */
    int bSeparate = 0;       /* Hash each table separately */
    int iSize = 224;         /* Hash algorithm to use */
    int bDebug = 0;          /* Only show the query that would have run */
    sqlite3_stmt *pStmt;     /* For querying tables names */
    char *zSql;              /* SQL to be run */
    char *zSep;              /* Separator */
    ShellText sSql;          /* Complete SQL for the query to run the hash */
    ShellText sQuery;        /* Set of queries used to read all content */
    open_db(p, 0);
    for(i=1; i<nArg; i++){
      const char *z = azArg[i];
      if( z[0]=='-' ){
        z++;
        if( z[0]=='-' ) z++;
        if( cli_strcmp(z,"schema")==0 ){
          bSchema = 1;
        }else
        if( cli_strcmp(z,"sha3-224")==0 || cli_strcmp(z,"sha3-256")==0
         || cli_strcmp(z,"sha3-384")==0 || cli_strcmp(z,"sha3-512")==0
        ){
          iSize = atoi(&z[5]);
        }else
        if( cli_strcmp(z,"debug")==0 ){
          bDebug = 1;
        }else
        {
          utf8_printf(stderr, "Unknown option \"%s\" on \"%s\"\n",
                      azArg[i], azArg[0]);
          showHelp(p->out, azArg[0]);
          rc = 1;

    initText(&sSql);
    appendText(&sSql, "WITH [sha3sum$query](a,b) AS(",0);
    zSep = "VALUES(";
    while( SQLITE_ROW==sqlite3_step(pStmt) ){
      const char *zTab = (const char*)sqlite3_column_text(pStmt,0);
      if( zTab==0 ) continue;
      if( zLike && sqlite3_strlike(zLike, zTab, 0)!=0 ) continue;
      if( cli_strncmp(zTab, "sqlite_",7)!=0 ){
        appendText(&sQuery,"SELECT * FROM ", 0);
        appendText(&sQuery,zTab,'"');
        appendText(&sQuery," NOT INDEXED;", 0);
      }else if( cli_strcmp(zTab, "sqlite_schema")==0 ){
        appendText(&sQuery,"SELECT type,name,tbl_name,sql FROM sqlite_schema"
                           " ORDER BY name;", 0);
      }else if( cli_strcmp(zTab, "sqlite_sequence")==0 ){
        appendText(&sQuery,"SELECT name,seq FROM sqlite_sequence"
                           " ORDER BY name;", 0);
      }else if( cli_strcmp(zTab, "sqlite_stat1")==0 ){
        appendText(&sQuery,"SELECT tbl,idx,stat FROM sqlite_stat1"
                           " ORDER BY tbl,idx;", 0);
      }else if( cli_strcmp(zTab, "sqlite_stat4")==0 ){
        appendText(&sQuery, "SELECT * FROM ", 0);
        appendText(&sQuery, zTab, 0);
        appendText(&sQuery, " ORDER BY tbl, idx, rowid;\n", 0);
      }
      appendText(&sSql, zSep, 0);
      appendText(&sSql, sQuery.z, '\'');
      sQuery.n = 0;

      utf8_printf(p->out, "%s\n", zSql);
    }else{
      shell_exec(p, zSql, 0);
    }
    sqlite3_free(zSql);
  }else

#if !defined(SQLITE_NOHAVE_SYSTEM) && !defined(SQLITE_SHELL_FIDDLE)
  if( c=='s'
   && (cli_strncmp(azArg[0], "shell", n)==0
       || cli_strncmp(azArg[0],"system",n)==0)
  ){
    char *zCmd;
    int i, x;
    failIfSafeMode(p, "cannot run .%s in safe mode", azArg[0]);
    if( nArg<2 ){
      raw_printf(stderr, "Usage: .system COMMAND\n");
      rc = 1;
      goto meta_command_exit;
    }
    zCmd = sqlite3_mprintf(strchr(azArg[1],' ')==0?"%s":"\"%s\"", azArg[1]);
    for(i=2; i<nArg && zCmd!=0; i++){
      zCmd = sqlite3_mprintf(strchr(azArg[i],' ')==0?"%z %s":"%z \"%s\"",
                             zCmd, azArg[i]);
    }
    x = zCmd!=0 ? system(zCmd) : 1;
    sqlite3_free(zCmd);
    if( x ) raw_printf(stderr, "System command returns %d\n", x);
  }else
#endif /* !defined(SQLITE_NOHAVE_SYSTEM) && !defined(SQLITE_SHELL_FIDDLE) */

  if( c=='s' && cli_strncmp(azArg[0], "show", n)==0 ){
    static const char *azBool[] = { "off", "on", "trigger", "full"};
    const char *zOut;
    int i;
    if( nArg!=1 ){
      raw_printf(stderr, "Usage: .show\n");
      rc = 1;
      goto meta_command_exit;

      raw_printf(p->out, "%d ", p->colWidth[i]);
    }
    raw_printf(p->out, "\n");
    utf8_printf(p->out, "%12.12s: %s\n", "filename",
                p->pAuxDb->zDbFilename ? p->pAuxDb->zDbFilename : "");
  }else

  if( c=='s' && cli_strncmp(azArg[0], "stats", n)==0 ){
    if( nArg==2 ){
      if( cli_strcmp(azArg[1],"stmt")==0 ){
        p->statsOn = 2;
      }else if( cli_strcmp(azArg[1],"vmstep")==0 ){
        p->statsOn = 3;
      }else{
        p->statsOn = (u8)booleanValue(azArg[1]);
      }
    }else if( nArg==1 ){
      display_stats(p->db, p, 0);
    }else{
      raw_printf(stderr, "Usage: .stats ?on|off|stmt|vmstep?\n");
      rc = 1;
    }
  }else

  if( (c=='t' && n>1 && cli_strncmp(azArg[0], "tables", n)==0)
   || (c=='i' && (cli_strncmp(azArg[0], "indices", n)==0
                 || cli_strncmp(azArg[0], "indexes", n)==0) )
  ){
    sqlite3_stmt *pStmt;
    char **azResult;
    int nRow, nAlloc;
    int ii;
    ShellText s;
    initText(&s);

      }
    }

    for(ii=0; ii<nRow; ii++) sqlite3_free(azResult[ii]);
    sqlite3_free(azResult);
  }else

#ifndef SQLITE_SHELL_FIDDLE
  /* Begin redirecting output to the file "testcase-out.txt" */
  if( c=='t' && cli_strcmp(azArg[0],"testcase")==0 ){
    output_reset(p);
    p->out = output_file_open("testcase-out.txt", 0);
    if( p->out==0 ){
      raw_printf(stderr, "Error: cannot open 'testcase-out.txt'\n");
    }
    if( nArg>=2 ){
      sqlite3_snprintf(sizeof(p->zTestcase), p->zTestcase, "%s", azArg[1]);
    }else{
      sqlite3_snprintf(sizeof(p->zTestcase), p->zTestcase, "?");
    }
  }else
#endif /* !defined(SQLITE_SHELL_FIDDLE) */

#ifndef SQLITE_UNTESTABLE
  if( c=='t' && n>=8 && cli_strncmp(azArg[0], "testctrl", n)==0 ){
    static const struct {
       const char *zCtrlName;   /* Name of a test-control option */
       int ctrlCode;            /* Integer code for that option */
       int unSafe;              /* Not valid for --safe mode */
       const char *zUsage;      /* Usage notes */
    } aCtrl[] = {
      { "always",             SQLITE_TESTCTRL_ALWAYS, 1,     "BOOLEAN"         },

    /* The argument can optionally begin with "-" or "--" */
    if( zCmd[0]=='-' && zCmd[1] ){
      zCmd++;
      if( zCmd[0]=='-' && zCmd[1] ) zCmd++;
    }

    /* --help lists all test-controls */
    if( cli_strcmp(zCmd,"help")==0 ){
      utf8_printf(p->out, "Available test-controls:\n");
      for(i=0; i<ArraySize(aCtrl); i++){
        utf8_printf(p->out, "  .testctrl %s %s\n",
                    aCtrl[i].zCtrlName, aCtrl[i].zUsage);
      }
      rc = 1;
      goto meta_command_exit;
    }

    /* convert testctrl text option to value. allow any unique prefix
    ** of the option name, or a numerical value. */
    n2 = strlen30(zCmd);
    for(i=0; i<ArraySize(aCtrl); i++){
      if( cli_strncmp(zCmd, aCtrl[i].zCtrlName, n2)==0 ){
        if( testctrl<0 ){
          testctrl = aCtrl[i].ctrlCode;
          iCtrl = i;
        }else{
          utf8_printf(stderr, "Error: ambiguous test-control: \"%s\"\n"
                              "Use \".testctrl --help\" for help\n", zCmd);
          rc = 1;

          break;

        /* sqlite3_test_control(int, int, sqlite3*) */
        case SQLITE_TESTCTRL_PRNG_SEED:
          if( nArg==3 || nArg==4 ){
            int ii = (int)integerValue(azArg[2]);
            sqlite3 *db;
            if( ii==0 && cli_strcmp(azArg[2],"random")==0 ){
              sqlite3_randomness(sizeof(ii),&ii);
              printf("-- random seed: %d\n", ii);
            }
            if( nArg==3 ){
              db = 0;
            }else{
              db = p->db;

      raw_printf(p->out, "%d\n", rc2);
    }else if( isOk==2 ){
      raw_printf(p->out, "0x%08x\n", rc2);
    }
  }else
#endif /* !defined(SQLITE_UNTESTABLE) */

  if( c=='t' && n>4 && cli_strncmp(azArg[0], "timeout", n)==0 ){
    open_db(p, 0);
    sqlite3_busy_timeout(p->db, nArg>=2 ? (int)integerValue(azArg[1]) : 0);
  }else

  if( c=='t' && n>=5 && cli_strncmp(azArg[0], "timer", n)==0 ){
    if( nArg==2 ){
      enableTimer = booleanValue(azArg[1]);
      if( enableTimer && !HAS_TIMER ){
        raw_printf(stderr, "Error: timer not available on this system.\n");
        enableTimer = 0;
      }
    }else{
      raw_printf(stderr, "Usage: .timer on|off\n");
      rc = 1;
    }
  }else

#ifndef SQLITE_OMIT_TRACE
  if( c=='t' && cli_strncmp(azArg[0], "trace", n)==0 ){
    int mType = 0;
    int jj;
    open_db(p, 0);
    for(jj=1; jj<nArg; jj++){
      const char *z = azArg[jj];
      if( z[0]=='-' ){
        if( optionMatch(z, "expanded") ){

      if( mType==0 ) mType = SQLITE_TRACE_STMT;
      sqlite3_trace_v2(p->db, mType, sql_trace_callback, p);
    }
  }else
#endif /* !defined(SQLITE_OMIT_TRACE) */

#if defined(SQLITE_DEBUG) && !defined(SQLITE_OMIT_VIRTUALTABLE)
  if( c=='u' && cli_strncmp(azArg[0], "unmodule", n)==0 ){
    int ii;
    int lenOpt;
    char *zOpt;
    if( nArg<2 ){
      raw_printf(stderr, "Usage: .unmodule [--allexcept] NAME ...\n");
      rc = 1;
      goto meta_command_exit;
    }
    open_db(p, 0);
    zOpt = azArg[1];
    if( zOpt[0]=='-' && zOpt[1]=='-' && zOpt[2]!=0 ) zOpt++;
    lenOpt = (int)strlen(zOpt);
    if( lenOpt>=3 && cli_strncmp(zOpt, "-allexcept",lenOpt)==0 ){
      assert( azArg[nArg]==0 );
      sqlite3_drop_modules(p->db, nArg>2 ? (const char**)(azArg+2) : 0);
    }else{
      for(ii=1; ii<nArg; ii++){
        sqlite3_create_module(p->db, azArg[ii], 0, 0);
      }
    }
  }else
#endif

#if SQLITE_USER_AUTHENTICATION
  if( c=='u' && cli_strncmp(azArg[0], "user", n)==0 ){
    if( nArg<2 ){
      raw_printf(stderr, "Usage: .user SUBCOMMAND ...\n");
      rc = 1;
      goto meta_command_exit;
    }
    open_db(p, 0);
    if( cli_strcmp(azArg[1],"login")==0 ){
      if( nArg!=4 ){
        raw_printf(stderr, "Usage: .user login USER PASSWORD\n");
        rc = 1;
        goto meta_command_exit;
      }
      rc = sqlite3_user_authenticate(p->db, azArg[2], azArg[3],
                                     strlen30(azArg[3]));
      if( rc ){
        utf8_printf(stderr, "Authentication failed for user %s\n", azArg[2]);
        rc = 1;
      }
    }else if( cli_strcmp(azArg[1],"add")==0 ){
      if( nArg!=5 ){
        raw_printf(stderr, "Usage: .user add USER PASSWORD ISADMIN\n");
        rc = 1;
        goto meta_command_exit;
      }
      rc = sqlite3_user_add(p->db, azArg[2], azArg[3], strlen30(azArg[3]),
                            booleanValue(azArg[4]));
      if( rc ){
        raw_printf(stderr, "User-Add failed: %d\n", rc);
        rc = 1;
      }
    }else if( cli_strcmp(azArg[1],"edit")==0 ){
      if( nArg!=5 ){
        raw_printf(stderr, "Usage: .user edit USER PASSWORD ISADMIN\n");
        rc = 1;
        goto meta_command_exit;
      }
      rc = sqlite3_user_change(p->db, azArg[2], azArg[3], strlen30(azArg[3]),
                              booleanValue(azArg[4]));
      if( rc ){
        raw_printf(stderr, "User-Edit failed: %d\n", rc);
        rc = 1;
      }
    }else if( cli_strcmp(azArg[1],"delete")==0 ){
      if( nArg!=3 ){
        raw_printf(stderr, "Usage: .user delete USER\n");
        rc = 1;
        goto meta_command_exit;
      }
      rc = sqlite3_user_delete(p->db, azArg[2]);
      if( rc ){
        raw_printf(stderr, "User-Delete failed: %d\n", rc);
        rc = 1;
      }
    }else{
      raw_printf(stderr, "Usage: .user login|add|edit|delete ...\n");
      rc = 1;
      goto meta_command_exit;
    }
  }else
#endif /* SQLITE_USER_AUTHENTICATION */

  if( c=='v' && cli_strncmp(azArg[0], "version", n)==0 ){
    utf8_printf(p->out, "SQLite %s %s\n" /*extra-version-info*/,
        sqlite3_libversion(), sqlite3_sourceid());
#if SQLITE_HAVE_ZLIB
    utf8_printf(p->out, "zlib version %s\n", zlibVersion());
#endif
#define CTIMEOPT_VAL_(opt) #opt
#define CTIMEOPT_VAL(opt) CTIMEOPT_VAL_(opt)
#if defined(__clang__) && defined(__clang_major__)
    utf8_printf(p->out, "clang-" CTIMEOPT_VAL(__clang_major__) "."
                    CTIMEOPT_VAL(__clang_minor__) "."
                    CTIMEOPT_VAL(__clang_patchlevel__) "\n");
#elif defined(_MSC_VER)
    utf8_printf(p->out, "msvc-" CTIMEOPT_VAL(_MSC_VER) "\n");
#elif defined(__GNUC__) && defined(__VERSION__)
    utf8_printf(p->out, "gcc-" __VERSION__ "\n");
#endif
  }else

  if( c=='v' && cli_strncmp(azArg[0], "vfsinfo", n)==0 ){
    const char *zDbName = nArg==2 ? azArg[1] : "main";
    sqlite3_vfs *pVfs = 0;
    if( p->db ){
      sqlite3_file_control(p->db, zDbName, SQLITE_FCNTL_VFS_POINTER, &pVfs);
      if( pVfs ){
        utf8_printf(p->out, "vfs.zName      = \"%s\"\n", pVfs->zName);
        raw_printf(p->out, "vfs.iVersion   = %d\n", pVfs->iVersion);
        raw_printf(p->out, "vfs.szOsFile   = %d\n", pVfs->szOsFile);
        raw_printf(p->out, "vfs.mxPathname = %d\n", pVfs->mxPathname);
      }
    }
  }else

  if( c=='v' && cli_strncmp(azArg[0], "vfslist", n)==0 ){
    sqlite3_vfs *pVfs;
    sqlite3_vfs *pCurrent = 0;
    if( p->db ){
      sqlite3_file_control(p->db, "main", SQLITE_FCNTL_VFS_POINTER, &pCurrent);
    }
    for(pVfs=sqlite3_vfs_find(0); pVfs; pVfs=pVfs->pNext){
      utf8_printf(p->out, "vfs.zName      = \"%s\"%s\n", pVfs->zName,
           pVfs==pCurrent ? "  <--- CURRENT" : "");
      raw_printf(p->out, "vfs.iVersion   = %d\n", pVfs->iVersion);
      raw_printf(p->out, "vfs.szOsFile   = %d\n", pVfs->szOsFile);
      raw_printf(p->out, "vfs.mxPathname = %d\n", pVfs->mxPathname);
      if( pVfs->pNext ){
        raw_printf(p->out, "-----------------------------------\n");
      }
    }
  }else

  if( c=='v' && cli_strncmp(azArg[0], "vfsname", n)==0 ){
    const char *zDbName = nArg==2 ? azArg[1] : "main";
    char *zVfsName = 0;
    if( p->db ){
      sqlite3_file_control(p->db, zDbName, SQLITE_FCNTL_VFSNAME, &zVfsName);
      if( zVfsName ){
        utf8_printf(p->out, "%s\n", zVfsName);
        sqlite3_free(zVfsName);
      }
    }
  }else

  if( c=='w' && cli_strncmp(azArg[0], "wheretrace", n)==0 ){
    unsigned int x = nArg>=2 ? (unsigned int)integerValue(azArg[1]) : 0xffffffff;
    sqlite3_test_control(SQLITE_TESTCTRL_TRACEFLAGS, 3, &x);
  }else

  if( c=='w' && cli_strncmp(azArg[0], "width", n)==0 ){
    int j;
    assert( nArg<=ArraySize(azArg) );
    p->nWidth = nArg-1;
    p->colWidth = realloc(p->colWidth, (p->nWidth+1)*sizeof(int)*2);
    if( p->colWidth==0 && p->nWidth>0 ) shell_out_of_memory();
    if( p->nWidth ) p->actualWidth = &p->colWidth[p->nWidth];
    for(j=1; j<nArg; j++){

  if( rc || zErrMsg ){
    char zPrefix[100];
    const char *zErrorTail;
    const char *zErrorType;
    if( zErrMsg==0 ){
      zErrorType = "Error";
      zErrorTail = sqlite3_errmsg(p->db);
    }else if( cli_strncmp(zErrMsg, "in prepare, ",12)==0 ){
      zErrorType = "Parse error";
      zErrorTail = &zErrMsg[12];
    }else if( cli_strncmp(zErrMsg, "stepping, ", 10)==0 ){
      zErrorType = "Runtime error";
      zErrorTail = &zErrMsg[10];
    }else{
      zErrorType = "Error";
      zErrorTail = zErrMsg;
    }
    if( in!=0 || !stdin_is_interactive ){

  return 0;
}

static void echo_group_input(ShellState *p, const char *zDo){
  if( ShellHasFlag(p, SHFLG_Echo) ) utf8_printf(p->out, "%s\n", zDo);
}

#ifdef SQLITE_SHELL_FIDDLE
/*
** Alternate one_input_line() impl for wasm mode. This is not in the primary impl
** because we need the global shellState and cannot access it from that function
** without moving lots of code around (creating a larger/messier diff).
*/
static char *one_input_line(FILE *in, char *zPrior, int isContinuation){
  /* Parse the next line from shellState.wasm.zInput. */
  const char *zBegin = shellState.wasm.zPos;
  const char *z = zBegin;
  char *zLine = 0;
  i64 nZ = 0;

  UNUSED_PARAMETER(in);
  UNUSED_PARAMETER(isContinuation);
  if(!z || !*z){
    return 0;
  }
  while(*z && isspace(*z)) ++z;
  zBegin = z;
  for(; *z && '\n'!=*z; ++nZ, ++z){}
  if(nZ>0 && '\r'==zBegin[nZ-1]){
    --nZ;
  }
  shellState.wasm.zPos = z;
  zLine = realloc(zPrior, nZ+1);
  shell_check_oom(zLine);
  memcpy(zLine, zBegin, nZ);
  zLine[nZ] = 0;
  return zLine;
}
#endif /* SQLITE_SHELL_FIDDLE */

/*
** Read input from *in and process it.  If *in==0 then input
** is interactive - the user is typing it it.  Otherwise, input
** is coming from a file or device.  A prompt is issued and history
** is saved only if input is interactive.  An interrupt signal will
** cause this routine to exit immediately, unless input is interactive.
**
** Return the number of errors.
*/
static int process_input(ShellState *p){
  char *zLine = 0;          /* A single input line */
  char *zSql = 0;           /* Accumulated SQL text */
  i64 nLine;                /* Length of current line */
  i64 nSql = 0;             /* Bytes of zSql[] used */
  i64 nAlloc = 0;           /* Allocated zSql[] space */
  int rc;                   /* Error code */
  int errCnt = 0;           /* Number of errors seen */
  i64 startline = 0;        /* Line number for start of current input */
  QuickScanState qss = QSS_Start; /* Accumulated line status (so far) */

  if( p->inputNesting==MAX_INPUT_NESTING ){
    /* This will be more informative in a later version. */
    utf8_printf(stderr,"Input nesting limit (%d) reached at line %d."
                " Check recursion.\n", MAX_INPUT_NESTING, p->lineno);
    return 1;

          errCnt++;
        }
      }
      qss = QSS_Start;
      continue;
    }
    /* No single-line dispositions remain; accumulate line(s). */
    nLine = strlen(zLine);
    if( nSql+nLine+2>=nAlloc ){
      /* Grow buffer by half-again increments when big. */
      nAlloc = nSql+(nSql>>1)+nLine+100;
      zSql = realloc(zSql, nAlloc);
      shell_check_oom(zSql);
    }
    if( nSql==0 ){
      i64 i;
      for(i=0; zLine[i] && IsSpace(zLine[i]); i++){}
      assert( nAlloc>0 && zSql!=0 );
      memcpy(zSql, zLine+i, nLine+1-i);
      startline = p->lineno;
      nSql = nLine-i;
    }else{
      zSql[nSql++] = '\n';

    home_dir = "c:\\";
  }
#endif

#endif /* !_WIN32_WCE */

  if( home_dir ){
    i64 n = strlen(home_dir) + 1;
    char *z = malloc( n );
    if( z ) memcpy(z, home_dir, n);
    home_dir = z;
  }

  return home_dir;
}

   && (defined(_MSC_VER) || (defined(UNICODE) && defined(__GNUC__)))
#    define SQLITE_SHELL_IS_UTF8          (0)
#  else
#    define SQLITE_SHELL_IS_UTF8          (1)
#  endif
#endif

#ifdef SQLITE_SHELL_FIDDLE
#  define main fiddle_main
#endif

#if SQLITE_SHELL_IS_UTF8
int SQLITE_CDECL main(int argc, char **argv){
#else
int SQLITE_CDECL wmain(int argc, wchar_t **wargv){
  char **argv;
#endif
#ifdef SQLITE_DEBUG
  sqlite3_int64 mem_main_enter = sqlite3_memory_used();
#endif
  char *zErrMsg = 0;
#ifdef SQLITE_SHELL_FIDDLE
#  define data shellState
#else
  ShellState data;
#endif
  const char *zInitFile = 0;
  int i;
  int rc = 0;
  int warnInmemoryDb = 0;
  int readStdin = 1;
  int nCmd = 0;
  char **azCmd = 0;
  const char *zVfs = 0;           /* Value of -vfs command-line option */
#if !SQLITE_SHELL_IS_UTF8
  char **argvToFree = 0;
  int argcToFree = 0;
#endif

  setBinaryMode(stdin, 0);
  setvbuf(stderr, 0, _IONBF, 0); /* Make sure stderr is unbuffered */
#ifdef SQLITE_SHELL_FIDDLE
  stdin_is_interactive = 0;
  stdout_is_console = 1;
  data.wasm.zDefaultDbName = "/fiddle.sqlite3";
#else
  stdin_is_interactive = isatty(0);
  stdout_is_console = isatty(1);
#endif

#if !defined(_WIN32_WCE)
  if( getenv("SQLITE_DEBUG_BREAK") ){

      raise(SIGTRAP);
#endif
    }
  }
#endif

#if USE_SYSTEM_SQLITE+0!=1
  if( cli_strncmp(sqlite3_sourceid(),SQLITE_SOURCE_ID,60)!=0 ){
    utf8_printf(stderr, "SQLite header and source version mismatch\n%s\n%s\n",
            sqlite3_sourceid(), SQLITE_SOURCE_ID);
    exit(1);
  }
#endif
  main_init(&data);