diff -r 5f8e5adbbed9 -r 29cda98b007e engine/sqlite/src/vdbeapi.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/engine/sqlite/src/vdbeapi.cpp	Thu Feb 25 14:29:19 2010 +0000
@@ -0,0 +1,1087 @@
+/*
+** 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;
+}