--- a/engine/sqlite/src/vdbeapi.cpp	Wed May 26 10:44:32 2010 +0100
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,1087 +0,0 @@
-/*
-** 2004 May 26
-**
-** 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 code use to implement APIs that are part of the
-** VDBE.
-*/
-#include "sqliteInt.h"
-#include "vdbeInt.h"
-
-/*
-** Return TRUE (non-zero) of the statement supplied as an argument needs
-** to be recompiled.  A statement needs to be recompiled whenever the
-** execution environment changes in a way that would alter the program
-** that sqlite3_prepare() generates.  For example, if new functions or
-** collating sequences are registered or if an authorizer function is
-** added or changed.
-*/
-EXPORT_C int sqlite3_expired(sqlite3_stmt *pStmt){
-  Vdbe *p = (Vdbe*)pStmt;
-  return p==0 || p->expired;
-}
-
-/*
-** The following routine destroys a virtual machine that is created by
-** the sqlite3_compile() routine. The integer returned is an SQLITE_
-** success/failure code that describes the result of executing the virtual
-** machine.
-**
-** This routine sets the error code and string returned by
-** sqlite3_errcode(), sqlite3_errmsg() and sqlite3_errmsg16().
-*/
-EXPORT_C int sqlite3_finalize(sqlite3_stmt *pStmt){
-  int rc;
-  if( pStmt==0 ){
-    rc = SQLITE_OK;
-  }else{
-    Vdbe *v = (Vdbe*)pStmt;
-    sqlite3_mutex *mutex = v->db->mutex;
-    sqlite3_mutex_enter(mutex);
-    rc = sqlite3VdbeFinalize(v);
-    sqlite3_mutex_leave(mutex);
-  }
-  return rc;
-}
-
-/*
-** Terminate the current execution of an SQL statement and reset it
-** back to its starting state so that it can be reused. A success code from
-** the prior execution is returned.
-**
-** This routine sets the error code and string returned by
-** sqlite3_errcode(), sqlite3_errmsg() and sqlite3_errmsg16().
-*/
-EXPORT_C int sqlite3_reset(sqlite3_stmt *pStmt){
-  int rc;
-  if( pStmt==0 ){
-    rc = SQLITE_OK;
-  }else{
-    Vdbe *v = (Vdbe*)pStmt;
-    sqlite3_mutex_enter(v->db->mutex);
-    rc = sqlite3VdbeReset(v);
-    sqlite3VdbeMakeReady(v, -1, 0, 0, 0);
-    assert( (rc & (v->db->errMask))==rc );
-    sqlite3_mutex_leave(v->db->mutex);
-  }
-  return rc;
-}
-
-/*
-** Set all the parameters in the compiled SQL statement to NULL.
-*/
-EXPORT_C int sqlite3_clear_bindings(sqlite3_stmt *pStmt){
-  int i;
-  int rc = SQLITE_OK;
-  Vdbe *v = (Vdbe*)pStmt;
-  sqlite3_mutex_enter(v->db->mutex);
-  for(i=1; rc==SQLITE_OK && i<=sqlite3_bind_parameter_count(pStmt); i++){
-    rc = sqlite3_bind_null(pStmt, i);
-  }
-  sqlite3_mutex_leave(v->db->mutex);
-  return rc;
-}
-
-
-/**************************** sqlite3_value_  *******************************
-** The following routines extract information from a Mem or sqlite3_value
-** structure.
-*/
-EXPORT_C const void *sqlite3_value_blob(sqlite3_value *pVal){
-  Mem *p = (Mem*)pVal;
-  if( p->flags & (MEM_Blob|MEM_Str) ){
-    sqlite3VdbeMemExpandBlob(p);
-    p->flags &= ~MEM_Str;
-    p->flags |= MEM_Blob;
-    return p->z;
-  }else{
-    return sqlite3_value_text(pVal);
-  }
-}
-EXPORT_C int sqlite3_value_bytes(sqlite3_value *pVal){
-  return sqlite3ValueBytes(pVal, SQLITE_UTF8);
-}
-EXPORT_C int sqlite3_value_bytes16(sqlite3_value *pVal){
-  return sqlite3ValueBytes(pVal, SQLITE_UTF16NATIVE);
-}
-EXPORT_C double sqlite3_value_double(sqlite3_value *pVal){
-  return sqlite3VdbeRealValue((Mem*)pVal);
-}
-EXPORT_C int sqlite3_value_int(sqlite3_value *pVal){
-  return sqlite3VdbeIntValue((Mem*)pVal);
-}
-EXPORT_C sqlite_int64 sqlite3_value_int64(sqlite3_value *pVal){
-  return sqlite3VdbeIntValue((Mem*)pVal);
-}
-EXPORT_C const unsigned char *sqlite3_value_text(sqlite3_value *pVal){
-  return (const unsigned char *)sqlite3ValueText(pVal, SQLITE_UTF8);
-}
-#ifndef SQLITE_OMIT_UTF16
-EXPORT_C const void *sqlite3_value_text16(sqlite3_value* pVal){
-  return sqlite3ValueText(pVal, SQLITE_UTF16NATIVE);
-}
-EXPORT_C const void *sqlite3_value_text16be(sqlite3_value *pVal){
-  return sqlite3ValueText(pVal, SQLITE_UTF16BE);
-}
-EXPORT_C const void *sqlite3_value_text16le(sqlite3_value *pVal){
-  return sqlite3ValueText(pVal, SQLITE_UTF16LE);
-}
-#endif /* SQLITE_OMIT_UTF16 */
-EXPORT_C int sqlite3_value_type(sqlite3_value* pVal){
-  return pVal->type;
-}
-
-/**************************** sqlite3_result_  *******************************
-** The following routines are used by user-defined functions to specify
-** the function result.
-*/
-EXPORT_C void sqlite3_result_blob(
-  sqlite3_context *pCtx, 
-  const void *z, 
-  int n, 
-  void (*xDel)(void *)
-){
-  assert( n>=0 );
-  assert( sqlite3_mutex_held(pCtx->s.db->mutex) );
-  sqlite3VdbeMemSetStr(&pCtx->s, (const char*)z, n, 0, xDel);
-}
-EXPORT_C void sqlite3_result_double(sqlite3_context *pCtx, double rVal){
-  assert( sqlite3_mutex_held(pCtx->s.db->mutex) );
-  sqlite3VdbeMemSetDouble(&pCtx->s, rVal);
-}
-EXPORT_C void sqlite3_result_error(sqlite3_context *pCtx, const char *z, int n){
-  assert( sqlite3_mutex_held(pCtx->s.db->mutex) );
-  pCtx->isError = 1;
-  sqlite3VdbeMemSetStr(&pCtx->s, z, n, SQLITE_UTF8, SQLITE_TRANSIENT);
-}
-#ifndef SQLITE_OMIT_UTF16
-EXPORT_C void sqlite3_result_error16(sqlite3_context *pCtx, const void *z, int n){
-  assert( sqlite3_mutex_held(pCtx->s.db->mutex) );
-  pCtx->isError = 1;
-  sqlite3VdbeMemSetStr(&pCtx->s, (const char*)z, n, SQLITE_UTF16NATIVE, SQLITE_TRANSIENT);
-}
-#endif
-EXPORT_C void sqlite3_result_int(sqlite3_context *pCtx, int iVal){
-  assert( sqlite3_mutex_held(pCtx->s.db->mutex) );
-  sqlite3VdbeMemSetInt64(&pCtx->s, (i64)iVal);
-}
-EXPORT_C void sqlite3_result_int64(sqlite3_context *pCtx, i64 iVal){
-  assert( sqlite3_mutex_held(pCtx->s.db->mutex) );
-  sqlite3VdbeMemSetInt64(&pCtx->s, iVal);
-}
-EXPORT_C void sqlite3_result_null(sqlite3_context *pCtx){
-  assert( sqlite3_mutex_held(pCtx->s.db->mutex) );
-  sqlite3VdbeMemSetNull(&pCtx->s);
-}
-EXPORT_C void sqlite3_result_text(
-  sqlite3_context *pCtx, 
-  const char *z, 
-  int n,
-  void (*xDel)(void *)
-){
-  assert( sqlite3_mutex_held(pCtx->s.db->mutex) );
-  sqlite3VdbeMemSetStr(&pCtx->s, z, n, SQLITE_UTF8, xDel);
-}
-#ifndef SQLITE_OMIT_UTF16
-EXPORT_C void sqlite3_result_text16(
-  sqlite3_context *pCtx, 
-  const void *z, 
-  int n, 
-  void (*xDel)(void *)
-){
-  assert( sqlite3_mutex_held(pCtx->s.db->mutex) );
-  sqlite3VdbeMemSetStr(&pCtx->s, (const char*)z, n, SQLITE_UTF16NATIVE, xDel);
-}
-EXPORT_C void sqlite3_result_text16be(
-  sqlite3_context *pCtx, 
-  const void *z, 
-  int n, 
-  void (*xDel)(void *)
-){
-  assert( sqlite3_mutex_held(pCtx->s.db->mutex) );
-  sqlite3VdbeMemSetStr(&pCtx->s, (const char*)z, n, SQLITE_UTF16BE, xDel);
-}
-EXPORT_C void sqlite3_result_text16le(
-  sqlite3_context *pCtx, 
-  const void *z, 
-  int n, 
-  void (*xDel)(void *)
-){
-  assert( sqlite3_mutex_held(pCtx->s.db->mutex) );
-  sqlite3VdbeMemSetStr(&pCtx->s, (const char*)z, n, SQLITE_UTF16LE, xDel);
-}
-#endif /* SQLITE_OMIT_UTF16 */
-EXPORT_C void sqlite3_result_value(sqlite3_context *pCtx, sqlite3_value *pValue){
-  assert( sqlite3_mutex_held(pCtx->s.db->mutex) );
-  sqlite3VdbeMemCopy(&pCtx->s, pValue);
-}
-EXPORT_C void sqlite3_result_zeroblob(sqlite3_context *pCtx, int n){
-  assert( sqlite3_mutex_held(pCtx->s.db->mutex) );
-  sqlite3VdbeMemSetZeroBlob(&pCtx->s, n);
-}
-
-/* Force an SQLITE_TOOBIG error. */
-EXPORT_C void sqlite3_result_error_toobig(sqlite3_context *pCtx){
-  assert( sqlite3_mutex_held(pCtx->s.db->mutex) );
-  sqlite3VdbeMemSetZeroBlob(&pCtx->s, SQLITE_MAX_LENGTH+1);
-}
-
-/* An SQLITE_NOMEM error. */
-EXPORT_C void sqlite3_result_error_nomem(sqlite3_context *pCtx){
-  assert( sqlite3_mutex_held(pCtx->s.db->mutex) );
-  sqlite3VdbeMemSetNull(&pCtx->s);
-  pCtx->isError = 1;
-  pCtx->s.db->mallocFailed = 1;
-}
-
-/*
-** Execute the statement pStmt, either until a row of data is ready, the
-** statement is completely executed or an error occurs.
-**
-** This routine implements the bulk of the logic behind the sqlite_step()
-** API.  The only thing omitted is the automatic recompile if a 
-** schema change has occurred.  That detail is handled by the
-** outer sqlite3_step() wrapper procedure.
-*/
-static int sqlite3Step(Vdbe *p){
-  sqlite3 *db;
-  int rc;
-
-  assert(p);
-  if( p->magic!=VDBE_MAGIC_RUN ){
-    return SQLITE_MISUSE;
-  }
-
-  /* Assert that malloc() has not failed */
-  db = p->db;
-  assert( !db->mallocFailed );
-
-  if( p->aborted ){
-    return SQLITE_ABORT;
-  }
-  if( p->pc<=0 && p->expired ){
-    if( p->rc==SQLITE_OK ){
-      p->rc = SQLITE_SCHEMA;
-    }
-    rc = SQLITE_ERROR;
-    goto end_of_step;
-  }
-  if( sqlite3SafetyOn(db) ){
-    p->rc = SQLITE_MISUSE;
-    return SQLITE_MISUSE;
-  }
-  if( p->pc<0 ){
-    /* If there are no other statements currently running, then
-    ** reset the interrupt flag.  This prevents a call to sqlite3_interrupt
-    ** from interrupting a statement that has not yet started.
-    */
-    if( db->activeVdbeCnt==0 ){
-      db->u1.isInterrupted = 0;
-    }
-
-#ifndef SQLITE_OMIT_TRACE
-    /* Invoke the trace callback if there is one
-    */
-    if( db->xTrace && !db->init.busy ){
-      assert( p->nOp>0 );
-      assert( p->aOp[p->nOp-1].opcode==OP_Noop );
-      assert( p->aOp[p->nOp-1].p3!=0 );
-      assert( p->aOp[p->nOp-1].p3type==P3_DYNAMIC );
-      sqlite3SafetyOff(db);
-      db->xTrace(db->pTraceArg, p->aOp[p->nOp-1].p3);
-      if( sqlite3SafetyOn(db) ){
-        p->rc = SQLITE_MISUSE;
-        return SQLITE_MISUSE;
-      }
-    }
-    if( db->xProfile && !db->init.busy ){
-      double rNow;
-      sqlite3OsCurrentTime(db->pVfs, &rNow);
-      p->startTime = (rNow - (int)rNow)*3600.0*24.0*1000000000.0;
-    }
-#endif
-
-    /* Print a copy of SQL as it is executed if the SQL_TRACE pragma is turned
-    ** on in debugging mode.
-    */
-#ifdef SQLITE_DEBUG
-    if( (db->flags & SQLITE_SqlTrace)!=0 ){
-      sqlite3DebugPrintf("SQL-trace: %s\n", p->aOp[p->nOp-1].p3);
-    }
-#endif /* SQLITE_DEBUG */
-
-    db->activeVdbeCnt++;
-    p->pc = 0;
-  }
-#ifndef SQLITE_OMIT_EXPLAIN
-  if( p->explain ){
-    rc = sqlite3VdbeList(p);
-  }else
-#endif /* SQLITE_OMIT_EXPLAIN */
-  {
-    rc = sqlite3VdbeExec(p);
-  }
-
-  if( sqlite3SafetyOff(db) ){
-    rc = SQLITE_MISUSE;
-  }
-
-#ifndef SQLITE_OMIT_TRACE
-  /* Invoke the profile callback if there is one
-  */
-  if( rc!=SQLITE_ROW && db->xProfile && !db->init.busy ){
-    double rNow;
-    u64 elapseTime;
-
-    sqlite3OsCurrentTime(db->pVfs, &rNow);
-    elapseTime = (rNow - (int)rNow)*3600.0*24.0*1000000000.0 - p->startTime;
-    assert( p->nOp>0 );
-    assert( p->aOp[p->nOp-1].opcode==OP_Noop );
-    assert( p->aOp[p->nOp-1].p3!=0 );
-    assert( p->aOp[p->nOp-1].p3type==P3_DYNAMIC );
-    db->xProfile(db->pProfileArg, p->aOp[p->nOp-1].p3, elapseTime);
-  }
-#endif
-
-  sqlite3Error(p->db, rc, 0);
-  p->rc = sqlite3ApiExit(p->db, p->rc);
-end_of_step:
-  assert( (rc&0xff)==rc );
-  if( p->zSql && (rc&0xff)<SQLITE_ROW ){
-    /* This behavior occurs if sqlite3_prepare_v2() was used to build
-    ** the prepared statement.  Return error codes directly */
-    sqlite3Error(p->db, p->rc, 0);
-    return p->rc;
-  }else{
-    /* This is for legacy sqlite3_prepare() builds and when the code
-    ** is SQLITE_ROW or SQLITE_DONE */
-    return rc;
-  }
-}
-
-/*
-** This is the top-level implementation of sqlite3_step().  Call
-** sqlite3Step() to do most of the work.  If a schema error occurs,
-** call sqlite3Reprepare() and try again.
-*/
-#ifdef SQLITE_OMIT_PARSER
-int sqlite3_step(sqlite3_stmt *pStmt){
-  int rc = SQLITE_MISUSE;
-  if( pStmt ){
-    Vdbe *v;
-    v = (Vdbe*)pStmt;
-    sqlite3_mutex_enter(v->db->mutex);
-    rc = sqlite3Step(v);
-    sqlite3_mutex_leave(v->db->mutex);
-  }
-  return rc;
-}
-#else
-EXPORT_C int sqlite3_step(sqlite3_stmt *pStmt){
-  int rc = SQLITE_MISUSE;
-  if( pStmt ){
-    int cnt = 0;
-    Vdbe *v = (Vdbe*)pStmt;
-    sqlite3 *db = v->db;
-    sqlite3_mutex_enter(db->mutex);
-    while( (rc = sqlite3Step(v))==SQLITE_SCHEMA
-           && cnt++ < 5
-           && sqlite3Reprepare(v) ){
-      sqlite3_reset(pStmt);
-      v->expired = 0;
-    }
-    if( rc==SQLITE_SCHEMA && v->zSql && db->pErr ){
-      /* This case occurs after failing to recompile an sql statement. 
-      ** The error message from the SQL compiler has already been loaded 
-      ** into the database handle. This block copies the error message 
-      ** from the database handle into the statement and sets the statement
-      ** program counter to 0 to ensure that when the statement is 
-      ** finalized or reset the parser error message is available via
-      ** sqlite3_errmsg() and sqlite3_errcode().
-      */
-      const char *zErr = (const char *)sqlite3_value_text(db->pErr); 
-      sqlite3_free(v->zErrMsg);
-      if( !db->mallocFailed ){
-        v->zErrMsg = sqlite3DbStrDup(db, zErr);
-      } else {
-        v->zErrMsg = 0;
-        v->rc = SQLITE_NOMEM;
-      }
-    }
-    rc = sqlite3ApiExit(db, rc);
-    sqlite3_mutex_leave(db->mutex);
-  }
-  return rc;
-}
-#endif
-
-/*
-** Extract the user data from a sqlite3_context structure and return a
-** pointer to it.
-*/
-EXPORT_C void *sqlite3_user_data(sqlite3_context *p){
-  assert( p && p->pFunc );
-  return p->pFunc->pUserData;
-}
-
-/*
-** The following is the implementation of an SQL function that always
-** fails with an error message stating that the function is used in the
-** wrong context.  The sqlite3_overload_function() API might construct
-** SQL function that use this routine so that the functions will exist
-** for name resolution but are actually overloaded by the xFindFunction
-** method of virtual tables.
-*/
-void sqlite3InvalidFunction(
-  sqlite3_context *context,  /* The function calling context */
-  int argc,                  /* Number of arguments to the function */
-  sqlite3_value **argv       /* Value of each argument */
-){
-  const char *zName = context->pFunc->zName;
-  char *zErr;
-  zErr = sqlite3MPrintf(0,
-      "unable to use function %s in the requested context", zName);
-  sqlite3_result_error(context, zErr, -1);
-  sqlite3_free(zErr);
-}
-
-/*
-** Allocate or return the aggregate context for a user function.  A new
-** context is allocated on the first call.  Subsequent calls return the
-** same context that was returned on prior calls.
-*/
-EXPORT_C void *sqlite3_aggregate_context(sqlite3_context *p, int nByte){
-  Mem *pMem;
-  assert( p && p->pFunc && p->pFunc->xStep );
-  assert( sqlite3_mutex_held(p->s.db->mutex) );
-  pMem = p->pMem;
-  if( (pMem->flags & MEM_Agg)==0 ){
-    if( nByte==0 ){
-      assert( pMem->flags==MEM_Null );
-      pMem->z = 0;
-    }else{
-      pMem->flags = MEM_Agg;
-      pMem->xDel = sqlite3_free;
-      pMem->u.pDef = p->pFunc;
-      pMem->z = (char*)sqlite3DbMallocZero(p->s.db, nByte);
-    }
-  }
-  return (void*)pMem->z;
-}
-
-/*
-** Return the auxilary data pointer, if any, for the iArg'th argument to
-** the user-function defined by pCtx.
-*/
-EXPORT_C void *sqlite3_get_auxdata(sqlite3_context *pCtx, int iArg){
-  VdbeFunc *pVdbeFunc;
-
-  assert( sqlite3_mutex_held(pCtx->s.db->mutex) );
-  pVdbeFunc = pCtx->pVdbeFunc;
-  if( !pVdbeFunc || iArg>=pVdbeFunc->nAux || iArg<0 ){
-    return 0;
-  }
-  return pVdbeFunc->apAux[iArg].pAux;
-}
-
-/*
-** Set the auxilary data pointer and delete function, for the iArg'th
-** argument to the user-function defined by pCtx. Any previous value is
-** deleted by calling the delete function specified when it was set.
-*/
-EXPORT_C void sqlite3_set_auxdata(
-  sqlite3_context *pCtx, 
-  int iArg, 
-  void *pAux, 
-  void (*xDelete)(void*)
-){
-	VdbeFunc::AuxData *pAuxData;
-  VdbeFunc *pVdbeFunc;
-  if( iArg<0 ) goto failed;
-
-  assert( sqlite3_mutex_held(pCtx->s.db->mutex) );
-  pVdbeFunc = pCtx->pVdbeFunc;
-  if( !pVdbeFunc || pVdbeFunc->nAux<=iArg ){
-    int nAux = (pVdbeFunc ? pVdbeFunc->nAux : 0);
-	int nMalloc = sizeof(VdbeFunc) + sizeof(VdbeFunc::AuxData)*iArg;
-    pVdbeFunc = (VdbeFunc*)sqlite3DbRealloc(pCtx->s.db, pVdbeFunc, nMalloc);
-    if( !pVdbeFunc ){
-      goto failed;
-    }
-    pCtx->pVdbeFunc = pVdbeFunc;
-	memset(&pVdbeFunc->apAux[nAux], 0, sizeof(VdbeFunc::AuxData)*(iArg+1-nAux));
-    pVdbeFunc->nAux = iArg+1;
-    pVdbeFunc->pFunc = pCtx->pFunc;
-  }
-
-  pAuxData = &pVdbeFunc->apAux[iArg];
-  if( pAuxData->pAux && pAuxData->xDelete ){
-    pAuxData->xDelete(pAuxData->pAux);
-  }
-  pAuxData->pAux = pAux;
-  pAuxData->xDelete = xDelete;
-  return;
-
-failed:
-  if( xDelete ){
-    xDelete(pAux);
-  }
-}
-
-/*
-** Return the number of times the Step function of a aggregate has been 
-** called.
-**
-** This function is deprecated.  Do not use it for new code.  It is
-** provide only to avoid breaking legacy code.  New aggregate function
-** implementations should keep their own counts within their aggregate
-** context.
-*/
-EXPORT_C int sqlite3_aggregate_count(sqlite3_context *p){
-  assert( p && p->pFunc && p->pFunc->xStep );
-  return p->pMem->n;
-}
-
-/*
-** Return the number of columns in the result set for the statement pStmt.
-*/
-EXPORT_C int sqlite3_column_count(sqlite3_stmt *pStmt){
-  Vdbe *pVm = (Vdbe *)pStmt;
-  return pVm ? pVm->nResColumn : 0;
-}
-
-/*
-** Return the number of values available from the current row of the
-** currently executing statement pStmt.
-*/
-EXPORT_C int sqlite3_data_count(sqlite3_stmt *pStmt){
-  Vdbe *pVm = (Vdbe *)pStmt;
-  if( pVm==0 || !pVm->resOnStack ) return 0;
-  return pVm->nResColumn;
-}
-
-
-/*
-** Check to see if column iCol of the given statement is valid.  If
-** it is, return a pointer to the Mem for the value of that column.
-** If iCol is not valid, return a pointer to a Mem which has a value
-** of NULL.
-*/
-static Mem *columnMem(sqlite3_stmt *pStmt, int i){
-  Vdbe *pVm;
-  int vals;
-  Mem *pOut;
-
-  pVm = (Vdbe *)pStmt;
-  if( pVm && pVm->resOnStack && i<pVm->nResColumn && i>=0 ){
-    sqlite3_mutex_enter(pVm->db->mutex);
-    vals = sqlite3_data_count(pStmt);
-    pOut = &pVm->pTos[(1-vals)+i];
-  }else{
-    static const Mem nullMem = {{0}, 0.0, 0, "", 0, MEM_Null, SQLITE_NULL };
-    if( pVm->db ){
-      sqlite3_mutex_enter(pVm->db->mutex);
-      sqlite3Error(pVm->db, SQLITE_RANGE, 0);
-    }
-    pOut = (Mem*)&nullMem;
-  }
-  return pOut;
-}
-
-/*
-** This function is called after invoking an sqlite3_value_XXX function on a 
-** column value (i.e. a value returned by evaluating an SQL expression in the
-** select list of a SELECT statement) that may cause a malloc() failure. If 
-** malloc() has failed, the threads mallocFailed flag is cleared and the result
-** code of statement pStmt set to SQLITE_NOMEM.
-**
-** Specifically, this is called from within:
-**
-**     sqlite3_column_int()
-**     sqlite3_column_int64()
-**     sqlite3_column_text()
-**     sqlite3_column_text16()
-**     sqlite3_column_real()
-**     sqlite3_column_bytes()
-**     sqlite3_column_bytes16()
-**
-** But not for sqlite3_column_blob(), which never calls malloc().
-*/
-static void columnMallocFailure(sqlite3_stmt *pStmt)
-{
-  /* If malloc() failed during an encoding conversion within an
-  ** sqlite3_column_XXX API, then set the return code of the statement to
-  ** SQLITE_NOMEM. The next call to _step() (if any) will return SQLITE_ERROR
-  ** and _finalize() will return NOMEM.
-  */
-  Vdbe *p = (Vdbe *)pStmt;
-  if( p ){
-    p->rc = sqlite3ApiExit(p->db, p->rc);
-    sqlite3_mutex_leave(p->db->mutex);
-  }
-}
-
-/**************************** sqlite3_column_  *******************************
-** The following routines are used to access elements of the current row
-** in the result set.
-*/
-EXPORT_C const void *sqlite3_column_blob(sqlite3_stmt *pStmt, int i){
-  const void *val;
-  val = sqlite3_value_blob( columnMem(pStmt,i) );
-  /* Even though there is no encoding conversion, value_blob() might
-  ** need to call malloc() to expand the result of a zeroblob() 
-  ** expression. 
-  */
-  columnMallocFailure(pStmt);
-  return val;
-}
-EXPORT_C int sqlite3_column_bytes(sqlite3_stmt *pStmt, int i){
-  int val = sqlite3_value_bytes( columnMem(pStmt,i) );
-  columnMallocFailure(pStmt);
-  return val;
-}
-EXPORT_C int sqlite3_column_bytes16(sqlite3_stmt *pStmt, int i){
-  int val = sqlite3_value_bytes16( columnMem(pStmt,i) );
-  columnMallocFailure(pStmt);
-  return val;
-}
-EXPORT_C double sqlite3_column_double(sqlite3_stmt *pStmt, int i){
-  double val = sqlite3_value_double( columnMem(pStmt,i) );
-  columnMallocFailure(pStmt);
-  return val;
-}
-EXPORT_C int sqlite3_column_int(sqlite3_stmt *pStmt, int i){
-  int val = sqlite3_value_int( columnMem(pStmt,i) );
-  columnMallocFailure(pStmt);
-  return val;
-}
-EXPORT_C sqlite_int64 sqlite3_column_int64(sqlite3_stmt *pStmt, int i){
-  sqlite_int64 val = sqlite3_value_int64( columnMem(pStmt,i) );
-  columnMallocFailure(pStmt);
-  return val;
-}
-EXPORT_C const unsigned char *sqlite3_column_text(sqlite3_stmt *pStmt, int i){
-  const unsigned char *val = sqlite3_value_text( columnMem(pStmt,i) );
-  columnMallocFailure(pStmt);
-  return val;
-}
-EXPORT_C sqlite3_value *sqlite3_column_value(sqlite3_stmt *pStmt, int i){
-  sqlite3_value *pOut = columnMem(pStmt, i);
-  columnMallocFailure(pStmt);
-  return pOut;
-}
-#ifndef SQLITE_OMIT_UTF16
-EXPORT_C const void *sqlite3_column_text16(sqlite3_stmt *pStmt, int i){
-  const void *val = sqlite3_value_text16( columnMem(pStmt,i) );
-  columnMallocFailure(pStmt);
-  return val;
-}
-#endif /* SQLITE_OMIT_UTF16 */
-EXPORT_C int sqlite3_column_type(sqlite3_stmt *pStmt, int i){
-  int iType = sqlite3_value_type( columnMem(pStmt,i) );
-  columnMallocFailure(pStmt);
-  return iType;
-}
-
-/* The following function is experimental and subject to change or
-** removal */
-/*int sqlite3_column_numeric_type(sqlite3_stmt *pStmt, int i){
-**  return sqlite3_value_numeric_type( columnMem(pStmt,i) );
-**}
-*/
-
-/*
-** Convert the N-th element of pStmt->pColName[] into a string using
-** xFunc() then return that string.  If N is out of range, return 0.
-**
-** There are up to 5 names for each column.  useType determines which
-** name is returned.  Here are the names:
-**
-**    0      The column name as it should be displayed for output
-**    1      The datatype name for the column
-**    2      The name of the database that the column derives from
-**    3      The name of the table that the column derives from
-**    4      The name of the table column that the result column derives from
-**
-** If the result is not a simple column reference (if it is an expression
-** or a constant) then useTypes 2, 3, and 4 return NULL.
-*/
-static const void *columnName(
-  sqlite3_stmt *pStmt,
-  int N,
-  const void *(*xFunc)(Mem*),
-  int useType
-){
-  const void *ret = 0;
-  Vdbe *p = (Vdbe *)pStmt;
-  int n;
-  
-
-  if( p!=0 ){
-    n = sqlite3_column_count(pStmt);
-    if( N<n && N>=0 ){
-      N += useType*n;
-      sqlite3_mutex_enter(p->db->mutex);
-      ret = xFunc(&p->aColName[N]);
-
-      /* A malloc may have failed inside of the xFunc() call. If this
-      ** is the case, clear the mallocFailed flag and return NULL.
-      */
-      if( p->db && p->db->mallocFailed ){
-        p->db->mallocFailed = 0;
-        ret = 0;
-      }
-      sqlite3_mutex_leave(p->db->mutex);
-    }
-  }
-  return ret;
-}
-
-/*
-** Return the name of the Nth column of the result set returned by SQL
-** statement pStmt.
-*/
-EXPORT_C const char *sqlite3_column_name(sqlite3_stmt *pStmt, int N){
-  return (const char*)columnName(
-      pStmt, N, (const void*(*)(Mem*))sqlite3_value_text, COLNAME_NAME);
-}
-#ifndef SQLITE_OMIT_UTF16
-EXPORT_C const void *sqlite3_column_name16(sqlite3_stmt *pStmt, int N){
-  return columnName(
-      pStmt, N, (const void*(*)(Mem*))sqlite3_value_text16, COLNAME_NAME);
-}
-#endif
-
-/*
-** Return the column declaration type (if applicable) of the 'i'th column
-** of the result set of SQL statement pStmt.
-*/
-EXPORT_C const char *sqlite3_column_decltype(sqlite3_stmt *pStmt, int N){
-  return (const char*)columnName(
-      pStmt, N, (const void*(*)(Mem*))sqlite3_value_text, COLNAME_DECLTYPE);
-}
-#ifndef SQLITE_OMIT_UTF16
-EXPORT_C const void *sqlite3_column_decltype16(sqlite3_stmt *pStmt, int N){
-  return columnName(
-      pStmt, N, (const void*(*)(Mem*))sqlite3_value_text16, COLNAME_DECLTYPE);
-}
-#endif /* SQLITE_OMIT_UTF16 */
-
-#ifdef SQLITE_ENABLE_COLUMN_METADATA
-/*
-** Return the name of the database from which a result column derives.
-** NULL is returned if the result column is an expression or constant or
-** anything else which is not an unabiguous reference to a database column.
-*/
-const char *sqlite3_column_database_name(sqlite3_stmt *pStmt, int N){
-  return columnName(
-      pStmt, N, (const void*(*)(Mem*))sqlite3_value_text, COLNAME_DATABASE);
-}
-#ifndef SQLITE_OMIT_UTF16
-const void *sqlite3_column_database_name16(sqlite3_stmt *pStmt, int N){
-  return columnName(
-      pStmt, N, (const void*(*)(Mem*))sqlite3_value_text16, COLNAME_DATABASE);
-}
-#endif /* SQLITE_OMIT_UTF16 */
-
-/*
-** Return the name of the table from which a result column derives.
-** NULL is returned if the result column is an expression or constant or
-** anything else which is not an unabiguous reference to a database column.
-*/
-const char *sqlite3_column_table_name(sqlite3_stmt *pStmt, int N){
-  return columnName(
-      pStmt, N, (const void*(*)(Mem*))sqlite3_value_text, COLNAME_TABLE);
-}
-#ifndef SQLITE_OMIT_UTF16
-const void *sqlite3_column_table_name16(sqlite3_stmt *pStmt, int N){
-  return columnName(
-      pStmt, N, (const void*(*)(Mem*))sqlite3_value_text16, COLNAME_TABLE);
-}
-#endif /* SQLITE_OMIT_UTF16 */
-
-/*
-** Return the name of the table column from which a result column derives.
-** NULL is returned if the result column is an expression or constant or
-** anything else which is not an unabiguous reference to a database column.
-*/
-const char *sqlite3_column_origin_name(sqlite3_stmt *pStmt, int N){
-  return columnName(
-      pStmt, N, (const void*(*)(Mem*))sqlite3_value_text, COLNAME_COLUMN);
-}
-#ifndef SQLITE_OMIT_UTF16
-const void *sqlite3_column_origin_name16(sqlite3_stmt *pStmt, int N){
-  return columnName(
-      pStmt, N, (const void*(*)(Mem*))sqlite3_value_text16, COLNAME_COLUMN);
-}
-#endif /* SQLITE_OMIT_UTF16 */
-#endif /* SQLITE_ENABLE_COLUMN_METADATA */
-
-
-/******************************* sqlite3_bind_  ***************************
-** 
-** Routines used to attach values to wildcards in a compiled SQL statement.
-*/
-/*
-** Unbind the value bound to variable i in virtual machine p. This is the 
-** the same as binding a NULL value to the column. If the "i" parameter is
-** out of range, then SQLITE_RANGE is returned. Othewise SQLITE_OK.
-**
-** The error code stored in database p->db is overwritten with the return
-** value in any case.
-*/
-static int vdbeUnbind(Vdbe *p, int i){
-  Mem *pVar;
-  if( p==0 || p->magic!=VDBE_MAGIC_RUN || p->pc>=0 ){
-    if( p ) sqlite3Error(p->db, SQLITE_MISUSE, 0);
-    return SQLITE_MISUSE;
-  }
-  if( i<1 || i>p->nVar ){
-    sqlite3Error(p->db, SQLITE_RANGE, 0);
-    return SQLITE_RANGE;
-  }
-  i--;
-  pVar = &p->aVar[i];
-  sqlite3VdbeMemRelease(pVar);
-  pVar->flags = MEM_Null;
-  sqlite3Error(p->db, SQLITE_OK, 0);
-  return SQLITE_OK;
-}
-
-/*
-** Bind a text or BLOB value.
-*/
-static int bindText(
-  sqlite3_stmt *pStmt,   /* The statement to bind against */
-  int i,                 /* Index of the parameter to bind */
-  const void *zData,     /* Pointer to the data to be bound */
-  int nData,             /* Number of bytes of data to be bound */
-  void (*xDel)(void*),   /* Destructor for the data */
-  int encoding           /* Encoding for the data */
-){
-  Vdbe *p = (Vdbe *)pStmt;
-  Mem *pVar;
-  int rc;
-
-  if( p==0 ){
-    return SQLITE_MISUSE;
-  }
-  sqlite3_mutex_enter(p->db->mutex);
-  rc = vdbeUnbind(p, i);
-  if( rc==SQLITE_OK && zData!=0 ){
-    pVar = &p->aVar[i-1];
-    rc = sqlite3VdbeMemSetStr(pVar, (const char*)zData, nData, encoding, xDel);
-    if( rc==SQLITE_OK && encoding!=0 ){
-      rc = sqlite3VdbeChangeEncoding(pVar, ENC(p->db));
-    }
-    sqlite3Error(p->db, rc, 0);
-    rc = sqlite3ApiExit(p->db, rc);
-  }
-  sqlite3_mutex_leave(p->db->mutex);
-  return rc;
-}
-
-
-/*
-** Bind a blob value to an SQL statement variable.
-*/
-EXPORT_C int sqlite3_bind_blob(
-  sqlite3_stmt *pStmt, 
-  int i, 
-  const void *zData, 
-  int nData, 
-  void (*xDel)(void*)
-){
-  return bindText(pStmt, i, zData, nData, xDel, 0);
-}
-EXPORT_C int sqlite3_bind_double(sqlite3_stmt *pStmt, int i, double rValue){
-  int rc;
-  Vdbe *p = (Vdbe *)pStmt;
-  sqlite3_mutex_enter(p->db->mutex);
-  rc = vdbeUnbind(p, i);
-  if( rc==SQLITE_OK ){
-    sqlite3VdbeMemSetDouble(&p->aVar[i-1], rValue);
-  }
-  sqlite3_mutex_leave(p->db->mutex);
-  return rc;
-}
-EXPORT_C int sqlite3_bind_int(sqlite3_stmt *p, int i, int iValue){
-  return sqlite3_bind_int64(p, i, (i64)iValue);
-}
-EXPORT_C int sqlite3_bind_int64(sqlite3_stmt *pStmt, int i, sqlite_int64 iValue){
-  int rc;
-  Vdbe *p = (Vdbe *)pStmt;
-  sqlite3_mutex_enter(p->db->mutex);
-  rc = vdbeUnbind(p, i);
-  if( rc==SQLITE_OK ){
-    sqlite3VdbeMemSetInt64(&p->aVar[i-1], iValue);
-  }
-  sqlite3_mutex_leave(p->db->mutex);
-  return rc;
-}
-EXPORT_C int sqlite3_bind_null(sqlite3_stmt *pStmt, int i){
-  int rc;
-  Vdbe *p = (Vdbe*)pStmt;
-  sqlite3_mutex_enter(p->db->mutex);
-  rc = vdbeUnbind(p, i);
-  sqlite3_mutex_leave(p->db->mutex);
-  return rc;
-}
-EXPORT_C int sqlite3_bind_text( 
-  sqlite3_stmt *pStmt, 
-  int i, 
-  const char *zData, 
-  int nData, 
-  void (*xDel)(void*)
-){
-  return bindText(pStmt, i, zData, nData, xDel, SQLITE_UTF8);
-}
-#ifndef SQLITE_OMIT_UTF16
-EXPORT_C int sqlite3_bind_text16(
-  sqlite3_stmt *pStmt, 
-  int i, 
-  const void *zData, 
-  int nData, 
-  void (*xDel)(void*)
-){
-  return bindText(pStmt, i, zData, nData, xDel, SQLITE_UTF16NATIVE);
-}
-#endif /* SQLITE_OMIT_UTF16 */
-EXPORT_C int sqlite3_bind_value(sqlite3_stmt *pStmt, int i, const sqlite3_value *pValue){
-  int rc;
-  Vdbe *p = (Vdbe *)pStmt;
-  sqlite3_mutex_enter(p->db->mutex);
-  rc = vdbeUnbind(p, i);
-  if( rc==SQLITE_OK ){
-    rc = sqlite3VdbeMemCopy(&p->aVar[i-1], pValue);
-  }
-  sqlite3_mutex_leave(p->db->mutex);
-  return rc;
-}
-EXPORT_C int sqlite3_bind_zeroblob(sqlite3_stmt *pStmt, int i, int n){
-  int rc;
-  Vdbe *p = (Vdbe *)pStmt;
-  sqlite3_mutex_enter(p->db->mutex);
-  rc = vdbeUnbind(p, i);
-  if( rc==SQLITE_OK ){
-    sqlite3VdbeMemSetZeroBlob(&p->aVar[i-1], n);
-  }
-  sqlite3_mutex_leave(p->db->mutex);
-  return rc;
-}
-
-/*
-** Return the number of wildcards that can be potentially bound to.
-** This routine is added to support DBD::SQLite.  
-*/
-EXPORT_C int sqlite3_bind_parameter_count(sqlite3_stmt *pStmt){
-  Vdbe *p = (Vdbe*)pStmt;
-  return p ? p->nVar : 0;
-}
-
-/*
-** Create a mapping from variable numbers to variable names
-** in the Vdbe.azVar[] array, if such a mapping does not already
-** exist.
-*/
-static void createVarMap(Vdbe *p){
-  if( !p->okVar ){
-    sqlite3_mutex_enter(p->db->mutex);
-    if( !p->okVar ){
-      int j;
-      Op *pOp;
-      for(j=0, pOp=p->aOp; j<p->nOp; j++, pOp++){
-        if( pOp->opcode==OP_Variable ){
-          assert( pOp->p1>0 && pOp->p1<=p->nVar );
-          p->azVar[pOp->p1-1] = pOp->p3;
-        }
-      }
-      p->okVar = 1;
-    }
-    sqlite3_mutex_leave(p->db->mutex);
-  }
-}
-
-/*
-** Return the name of a wildcard parameter.  Return NULL if the index
-** is out of range or if the wildcard is unnamed.
-**
-** The result is always UTF-8.
-*/
-EXPORT_C const char *sqlite3_bind_parameter_name(sqlite3_stmt *pStmt, int i){
-  Vdbe *p = (Vdbe*)pStmt;
-  if( p==0 || i<1 || i>p->nVar ){
-    return 0;
-  }
-  createVarMap(p);
-  return p->azVar[i-1];
-}
-
-/*
-** Given a wildcard parameter name, return the index of the variable
-** with that name.  If there is no variable with the given name,
-** return 0.
-*/
-EXPORT_C int sqlite3_bind_parameter_index(sqlite3_stmt *pStmt, const char *zName){
-  Vdbe *p = (Vdbe*)pStmt;
-  int i;
-  if( p==0 ){
-    return 0;
-  }
-  createVarMap(p); 
-  if( zName ){
-    for(i=0; i<p->nVar; i++){
-      const char *z = p->azVar[i];
-      if( z && strcmp(z,zName)==0 ){
-        return i+1;
-      }
-    }
-  }
-  return 0;
-}
-
-/*
-** Transfer all bindings from the first statement over to the second.
-** If the two statements contain a different number of bindings, then
-** an SQLITE_ERROR is returned.
-*/
-EXPORT_C int sqlite3_transfer_bindings(sqlite3_stmt *pFromStmt, sqlite3_stmt *pToStmt){
-  Vdbe *pFrom = (Vdbe*)pFromStmt;
-  Vdbe *pTo = (Vdbe*)pToStmt;
-  int i, rc = SQLITE_OK;
-  if( (pFrom->magic!=VDBE_MAGIC_RUN && pFrom->magic!=VDBE_MAGIC_HALT)
-    || (pTo->magic!=VDBE_MAGIC_RUN && pTo->magic!=VDBE_MAGIC_HALT)
-    || pTo->db!=pFrom->db ){
-    return SQLITE_MISUSE;
-  }
-  if( pFrom->nVar!=pTo->nVar ){
-    return SQLITE_ERROR;
-  }
-  sqlite3_mutex_enter(pTo->db->mutex);
-  for(i=0; rc==SQLITE_OK && i<pFrom->nVar; i++){
-    sqlite3MallocDisallow();
-    rc = sqlite3VdbeMemMove(&pTo->aVar[i], &pFrom->aVar[i]);
-    sqlite3MallocAllow();
-  }
-  sqlite3_mutex_leave(pTo->db->mutex);
-  assert( rc==SQLITE_OK || rc==SQLITE_NOMEM );
-  return rc;
-}
-
-/*
-** Return the sqlite3* database handle to which the prepared statement given
-** in the argument belongs.  This is the same database handle that was
-** the first argument to the sqlite3_prepare() that was used to create
-** the statement in the first place.
-*/
-EXPORT_C sqlite3 *sqlite3_db_handle(sqlite3_stmt *pStmt){
-  return pStmt ? ((Vdbe*)pStmt)->db : 0;
-}