engine/sqlite/src/main.cpp
changeset 2 29cda98b007e
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/engine/sqlite/src/main.cpp	Thu Feb 25 14:29:19 2010 +0000
@@ -0,0 +1,1494 @@
+/*
+** 2001 September 15
+**
+** 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.
+**
+*************************************************************************
+** Main file for the SQLite library.  The routines in this file
+** implement the programmer interface to the library.  Routines in
+** other files are for internal use by SQLite and should not be
+** accessed by users of the library.
+**
+** $Id: main.cpp 1282 2008-11-13 09:31:33Z LarsPson $
+*/
+#include "sqliteInt.h"
+#include <ctype.h>
+#include <stdio.h>
+#include <string.h>
+
+/*
+** The version of the library
+*/
+EXPORT_C const char *sqlite3_libversion(void){ return sqlite3_version; }
+EXPORT_C int sqlite3_libversion_number(void){ return SQLITE_VERSION_NUMBER; }
+EXPORT_C int sqlite3_threadsafe(void){ return SQLITE_THREADSAFE; }
+
+/*
+** If the following function pointer is not NULL and if
+** SQLITE_ENABLE_IOTRACE is enabled, then messages describing
+** I/O active are written using this function.  These messages
+** are intended for debugging activity only.
+*/
+void (*sqlite3_io_trace)(const char*, ...) = 0;
+
+/*
+** If the following global variable points to a string which is the
+** name of a directory, then that directory will be used to store
+** temporary files.
+**
+** See also the "PRAGMA temp_store_directory" SQL command.
+*/
+char *sqlite3_temp_directory = 0;
+
+
+/*
+** This is the default collating function named "BINARY" which is always
+** available.
+*/
+static int binCollFunc(
+  void *NotUsed,
+  int nKey1, const void *pKey1,
+  int nKey2, const void *pKey2
+){
+  int rc, n;
+  n = nKey1<nKey2 ? nKey1 : nKey2;
+  rc = memcmp(pKey1, pKey2, n);
+  if( rc==0 ){
+    rc = nKey1 - nKey2;
+  }
+  return rc;
+}
+
+/*
+** Another built-in collating sequence: NOCASE. 
+**
+** This collating sequence is intended to be used for "case independant
+** comparison". SQLite's knowledge of upper and lower case equivalents
+** extends only to the 26 characters used in the English language.
+**
+** At the moment there is only a UTF-8 implementation.
+*/
+static int nocaseCollatingFunc(
+  void *NotUsed,
+  int nKey1, const void *pKey1,
+  int nKey2, const void *pKey2
+){
+  int r = sqlite3StrNICmp(
+      (const char *)pKey1, (const char *)pKey2, (nKey1<nKey2)?nKey1:nKey2);
+  if( 0==r ){
+    r = nKey1-nKey2;
+  }
+  return r;
+}
+
+/*
+** Return the ROWID of the most recent insert
+*/
+EXPORT_C sqlite_int64 sqlite3_last_insert_rowid(sqlite3 *db){
+  return db->lastRowid;
+}
+
+/*
+** Return the number of changes in the most recent call to sqlite3_exec().
+*/
+EXPORT_C int sqlite3_changes(sqlite3 *db){
+  return db->nChange;
+}
+
+/*
+** Return the number of changes since the database handle was opened.
+*/
+EXPORT_C int sqlite3_total_changes(sqlite3 *db){
+  return db->nTotalChange;
+}
+
+/*
+** Close an existing SQLite database
+*/
+EXPORT_C int sqlite3_close(sqlite3 *db){
+  HashElem *i;
+  int j;
+
+  if( !db ){
+    return SQLITE_OK;
+  }
+  if( sqlite3SafetyCheck(db) ){
+    return SQLITE_MISUSE;
+  }
+  sqlite3_mutex_enter(db->mutex);
+
+#ifdef SQLITE_SSE
+  {
+    extern void sqlite3SseCleanup(sqlite3*);
+    sqlite3SseCleanup(db);
+  }
+#endif 
+
+  sqlite3ResetInternalSchema(db, 0);
+
+  /* If a transaction is open, the ResetInternalSchema() call above
+  ** will not have called the xDisconnect() method on any virtual
+  ** tables in the db->aVTrans[] array. The following sqlite3VtabRollback()
+  ** call will do so. We need to do this before the check for active
+  ** SQL statements below, as the v-table implementation may be storing
+  ** some prepared statements internally.
+  */
+  sqlite3VtabRollback(db);
+
+  /* If there are any outstanding VMs, return SQLITE_BUSY. */
+  if( db->pVdbe ){
+    sqlite3Error(db, SQLITE_BUSY, 
+        "Unable to close due to unfinalised statements");
+    sqlite3_mutex_leave(db->mutex);
+    return SQLITE_BUSY;
+  }
+  assert( !sqlite3SafetyCheck(db) );
+
+  /* FIX ME: db->magic may be set to SQLITE_MAGIC_CLOSED if the database
+  ** cannot be opened for some reason. So this routine needs to run in
+  ** that case. But maybe there should be an extra magic value for the
+  ** "failed to open" state.
+  **
+  ** TODO: Coverage tests do not test the case where this condition is
+  ** true. It's hard to see how to cause it without messing with threads.
+  */
+  if( db->magic!=SQLITE_MAGIC_CLOSED && sqlite3SafetyOn(db) ){
+    /* printf("DID NOT CLOSE\n"); fflush(stdout); */
+    sqlite3_mutex_leave(db->mutex);
+    return SQLITE_ERROR;
+  }
+
+  for(j=0; j<db->nDb; j++){
+    struct Db *pDb = &db->aDb[j];
+    if( pDb->pBt ){
+      sqlite3BtreeClose(pDb->pBt);
+      pDb->pBt = 0;
+      if( j!=1 ){
+        pDb->pSchema = 0;
+      }
+    }
+  }
+  sqlite3ResetInternalSchema(db, 0);
+  assert( db->nDb<=2 );
+  assert( db->aDb==db->aDbStatic );
+  for(i=sqliteHashFirst(&db->aFunc); i; i=sqliteHashNext(i)){
+    FuncDef *pFunc, *pNext;
+    for(pFunc = (FuncDef*)sqliteHashData(i); pFunc; pFunc=pNext){
+      pNext = pFunc->pNext;
+      sqlite3_free(pFunc);
+    }
+  }
+
+  for(i=sqliteHashFirst(&db->aCollSeq); i; i=sqliteHashNext(i)){
+    CollSeq *pColl = (CollSeq *)sqliteHashData(i);
+    /* Invoke any destructors registered for collation sequence user data. */
+    for(j=0; j<3; j++){
+      if( pColl[j].xDel ){
+        pColl[j].xDel(pColl[j].pUser);
+      }
+    }
+    sqlite3_free(pColl);
+  }
+  sqlite3HashClear(&db->aCollSeq);
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+  for(i=sqliteHashFirst(&db->aModule); i; i=sqliteHashNext(i)){
+    Module *pMod = (Module *)sqliteHashData(i);
+    if( pMod->xDestroy ){
+      pMod->xDestroy(pMod->pAux);
+    }
+    sqlite3_free(pMod);
+  }
+  sqlite3HashClear(&db->aModule);
+#endif
+
+  sqlite3HashClear(&db->aFunc);
+  sqlite3Error(db, SQLITE_OK, 0); /* Deallocates any cached error strings. */
+  if( db->pErr ){
+    sqlite3ValueFree(db->pErr);
+  }
+  sqlite3CloseExtensions(db);
+
+  db->magic = SQLITE_MAGIC_ERROR;
+
+  /* The temp-database schema is allocated differently from the other schema
+  ** objects (using sqliteMalloc() directly, instead of sqlite3BtreeSchema()).
+  ** So it needs to be freed here. Todo: Why not roll the temp schema into
+  ** the same sqliteMalloc() as the one that allocates the database 
+  ** structure?
+  */
+  sqlite3_free(db->aDb[1].pSchema);
+  sqlite3_mutex_leave(db->mutex);
+  sqlite3_mutex_free(db->mutex);
+  sqlite3_free(db);
+  return SQLITE_OK;
+}
+
+/*
+** Rollback all database files.
+*/
+void sqlite3RollbackAll(sqlite3 *db){
+  int i;
+  int inTrans = 0;
+  assert( sqlite3_mutex_held(db->mutex) );
+  sqlite3MallocEnterBenignBlock(1);                 /* Enter benign region */
+  for(i=0; i<db->nDb; i++){
+    if( db->aDb[i].pBt ){
+      if( sqlite3BtreeIsInTrans(db->aDb[i].pBt) ){
+        inTrans = 1;
+      }
+      sqlite3BtreeRollback(db->aDb[i].pBt);
+      db->aDb[i].inTrans = 0;
+    }
+  }
+  sqlite3VtabRollback(db);
+  sqlite3MallocLeaveBenignBlock();                 /* Leave benign region */
+
+  if( db->flags&SQLITE_InternChanges ){
+    sqlite3ExpirePreparedStatements(db);
+    sqlite3ResetInternalSchema(db, 0);
+  }
+
+  /* If one has been configured, invoke the rollback-hook callback */
+  if( db->xRollbackCallback && (inTrans || !db->autoCommit) ){
+    db->xRollbackCallback(db->pRollbackArg);
+  }
+}
+
+/*
+** Return a static string that describes the kind of error specified in the
+** argument.
+*/
+const char *sqlite3ErrStr(int rc){
+  const char *z;
+  switch( rc & 0xff ){
+    case SQLITE_ROW:
+    case SQLITE_DONE:
+    case SQLITE_OK:         z = "not an error";                          break;
+    case SQLITE_ERROR:      z = "SQL logic error or missing database";   break;
+    case SQLITE_PERM:       z = "access permission denied";              break;
+    case SQLITE_ABORT:      z = "callback requested query abort";        break;
+    case SQLITE_BUSY:       z = "database is locked";                    break;
+    case SQLITE_LOCKED:     z = "database table is locked";              break;
+    case SQLITE_NOMEM:      z = "out of memory";                         break;
+    case SQLITE_READONLY:   z = "attempt to write a readonly database";  break;
+    case SQLITE_INTERRUPT:  z = "interrupted";                           break;
+    case SQLITE_IOERR:      z = "disk I/O error";                        break;
+    case SQLITE_CORRUPT:    z = "database disk image is malformed";      break;
+    case SQLITE_FULL:       z = "database or disk is full";              break;
+    case SQLITE_CANTOPEN:   z = "unable to open database file";          break;
+    case SQLITE_EMPTY:      z = "table contains no data";                break;
+    case SQLITE_SCHEMA:     z = "database schema has changed";           break;
+    case SQLITE_TOOBIG:     z = "String or BLOB exceeded size limit";    break;
+    case SQLITE_CONSTRAINT: z = "constraint failed";                     break;
+    case SQLITE_MISMATCH:   z = "datatype mismatch";                     break;
+    case SQLITE_MISUSE:     z = "library routine called out of sequence";break;
+    case SQLITE_NOLFS:      z = "kernel lacks large file support";       break;
+    case SQLITE_AUTH:       z = "authorization denied";                  break;
+    case SQLITE_FORMAT:     z = "auxiliary database format error";       break;
+    case SQLITE_RANGE:      z = "bind or column index out of range";     break;
+    case SQLITE_NOTADB:     z = "file is encrypted or is not a database";break;
+    default:                z = "unknown error";                         break;
+  }
+  return z;
+}
+
+/*
+** This routine implements a busy callback that sleeps and tries
+** again until a timeout value is reached.  The timeout value is
+** an integer number of milliseconds passed in as the first
+** argument.
+*/
+static int sqliteDefaultBusyCallback(
+ void *ptr,               /* Database connection */
+ int count                /* Number of times table has been busy */
+){
+#if OS_WIN || (defined(HAVE_USLEEP) && HAVE_USLEEP)
+  static const u8 delays[] =
+     { 1, 2, 5, 10, 15, 20, 25, 25,  25,  50,  50, 100 };
+  static const u8 totals[] =
+     { 0, 1, 3,  8, 18, 33, 53, 78, 103, 128, 178, 228 };
+# define NDELAY (sizeof(delays)/sizeof(delays[0]))
+  sqlite3 *db = (sqlite3 *)ptr;
+  int timeout = db->busyTimeout;
+  int delay, prior;
+
+  assert( count>=0 );
+  if( count < NDELAY ){
+    delay = delays[count];
+    prior = totals[count];
+  }else{
+    delay = delays[NDELAY-1];
+    prior = totals[NDELAY-1] + delay*(count-(NDELAY-1));
+  }
+  if( prior + delay > timeout ){
+    delay = timeout - prior;
+    if( delay<=0 ) return 0;
+  }
+  sqlite3OsSleep(db->pVfs, delay*1000);
+  return 1;
+#else
+  sqlite3 *db = (sqlite3 *)ptr;
+  int timeout = ((sqlite3 *)ptr)->busyTimeout;
+  if( (count+1)*1000 > timeout ){
+    return 0;
+  }
+  sqlite3OsSleep(db->pVfs, 1000000);
+  return 1;
+#endif
+}
+
+/*
+** Invoke the given busy handler.
+**
+** This routine is called when an operation failed with a lock.
+** If this routine returns non-zero, the lock is retried.  If it
+** returns 0, the operation aborts with an SQLITE_BUSY error.
+*/
+int sqlite3InvokeBusyHandler(BusyHandler *p){
+  int rc;
+  if( p==0 || p->xFunc==0 || p->nBusy<0 ) return 0;
+  rc = p->xFunc(p->pArg, p->nBusy);
+  if( rc==0 ){
+    p->nBusy = -1;
+  }else{
+    p->nBusy++;
+  }
+  return rc; 
+}
+
+/*
+** This routine sets the busy callback for an Sqlite database to the
+** given callback function with the given argument.
+*/
+EXPORT_C int sqlite3_busy_handler(
+  sqlite3 *db,
+  int (*xBusy)(void*,int),
+  void *pArg
+){
+  if( sqlite3SafetyCheck(db) ){
+    return SQLITE_MISUSE;
+  }
+  sqlite3_mutex_enter(db->mutex);
+  db->busyHandler.xFunc = xBusy;
+  db->busyHandler.pArg = pArg;
+  db->busyHandler.nBusy = 0;
+  sqlite3_mutex_leave(db->mutex);
+  return SQLITE_OK;
+}
+
+#ifndef SQLITE_OMIT_PROGRESS_CALLBACK
+/*
+** This routine sets the progress callback for an Sqlite database to the
+** given callback function with the given argument. The progress callback will
+** be invoked every nOps opcodes.
+*/
+EXPORT_C void sqlite3_progress_handler(
+  sqlite3 *db, 
+  int nOps,
+  int (*xProgress)(void*), 
+  void *pArg
+){
+  if( !sqlite3SafetyCheck(db) ){
+    sqlite3_mutex_enter(db->mutex);
+    if( nOps>0 ){
+      db->xProgress = xProgress;
+      db->nProgressOps = nOps;
+      db->pProgressArg = pArg;
+    }else{
+      db->xProgress = 0;
+      db->nProgressOps = 0;
+      db->pProgressArg = 0;
+    }
+    sqlite3_mutex_leave(db->mutex);
+  }
+}
+#endif
+
+
+/*
+** This routine installs a default busy handler that waits for the
+** specified number of milliseconds before returning 0.
+*/
+EXPORT_C int sqlite3_busy_timeout(sqlite3 *db, int ms){
+  if( sqlite3SafetyCheck(db) ){
+    return SQLITE_MISUSE;
+  }
+  if( ms>0 ){
+    db->busyTimeout = ms;
+    sqlite3_busy_handler(db, sqliteDefaultBusyCallback, (void*)db);
+  }else{
+    sqlite3_busy_handler(db, NULL, NULL);
+  }
+  return SQLITE_OK;
+}
+
+/*
+** Cause any pending operation to stop at its earliest opportunity.
+*/
+EXPORT_C void sqlite3_interrupt(sqlite3 *db){
+  if( db && (db->magic==SQLITE_MAGIC_OPEN || db->magic==SQLITE_MAGIC_BUSY) ){
+    db->u1.isInterrupted = 1;
+  }
+}
+
+
+/*
+** This function is exactly the same as sqlite3_create_function(), except
+** that it is designed to be called by internal code. The difference is
+** that if a malloc() fails in sqlite3_create_function(), an error code
+** is returned and the mallocFailed flag cleared. 
+*/
+int sqlite3CreateFunc(
+  sqlite3 *db,
+  const char *zFunctionName,
+  int nArg,
+  int enc,
+  void *pUserData,
+  void (*xFunc)(sqlite3_context*,int,sqlite3_value **),
+  void (*xStep)(sqlite3_context*,int,sqlite3_value **),
+  void (*xFinal)(sqlite3_context*)
+){
+  FuncDef *p;
+  int nName;
+
+  assert( sqlite3_mutex_held(db->mutex) );
+  if( sqlite3SafetyCheck(db) ){
+    return SQLITE_MISUSE;
+  }
+  if( zFunctionName==0 ||
+      (xFunc && (xFinal || xStep)) || 
+      (!xFunc && (xFinal && !xStep)) ||
+      (!xFunc && (!xFinal && xStep)) ||
+      (nArg<-1 || nArg>127) ||
+      (255<(nName = strlen(zFunctionName))) ){
+    sqlite3Error(db, SQLITE_ERROR, "bad parameters");
+    return SQLITE_ERROR;
+  }
+  
+#ifndef SQLITE_OMIT_UTF16
+  /* If SQLITE_UTF16 is specified as the encoding type, transform this
+  ** to one of SQLITE_UTF16LE or SQLITE_UTF16BE using the
+  ** SQLITE_UTF16NATIVE macro. SQLITE_UTF16 is not used internally.
+  **
+  ** If SQLITE_ANY is specified, add three versions of the function
+  ** to the hash table.
+  */
+  if( enc==SQLITE_UTF16 ){
+    enc = SQLITE_UTF16NATIVE;
+  }else if( enc==SQLITE_ANY ){
+    int rc;
+    rc = sqlite3CreateFunc(db, zFunctionName, nArg, SQLITE_UTF8,
+         pUserData, xFunc, xStep, xFinal);
+    if( rc==SQLITE_OK ){
+      rc = sqlite3CreateFunc(db, zFunctionName, nArg, SQLITE_UTF16LE,
+          pUserData, xFunc, xStep, xFinal);
+    }
+    if( rc!=SQLITE_OK ){
+      return rc;
+    }
+    enc = SQLITE_UTF16BE;
+  }
+#else
+  enc = SQLITE_UTF8;
+#endif
+  
+  /* Check if an existing function is being overridden or deleted. If so,
+  ** and there are active VMs, then return SQLITE_BUSY. If a function
+  ** is being overridden/deleted but there are no active VMs, allow the
+  ** operation to continue but invalidate all precompiled statements.
+  */
+  p = sqlite3FindFunction(db, zFunctionName, nName, nArg, enc, 0);
+  if( p && p->iPrefEnc==enc && p->nArg==nArg ){
+    if( db->activeVdbeCnt ){
+      sqlite3Error(db, SQLITE_BUSY, 
+        "Unable to delete/modify user-function due to active statements");
+      assert( !db->mallocFailed );
+      return SQLITE_BUSY;
+    }else{
+      sqlite3ExpirePreparedStatements(db);
+    }
+  }
+
+  p = sqlite3FindFunction(db, zFunctionName, nName, nArg, enc, 1);
+  assert(p || db->mallocFailed);
+  if( !p ){
+    return SQLITE_NOMEM;
+  }
+  p->flags = 0;
+  p->xFunc = xFunc;
+  p->xStep = xStep;
+  p->xFinalize = xFinal;
+  p->pUserData = pUserData;
+  p->nArg = nArg;
+  return SQLITE_OK;
+}
+
+/*
+** Create new user functions.
+*/
+EXPORT_C int sqlite3_create_function(
+  sqlite3 *db,
+  const char *zFunctionName,
+  int nArg,
+  int enc,
+  void *p,
+  void (*xFunc)(sqlite3_context*,int,sqlite3_value **),
+  void (*xStep)(sqlite3_context*,int,sqlite3_value **),
+  void (*xFinal)(sqlite3_context*)
+){
+  int rc;
+  sqlite3_mutex_enter(db->mutex);
+  assert( !db->mallocFailed );
+  rc = sqlite3CreateFunc(db, zFunctionName, nArg, enc, p, xFunc, xStep, xFinal);
+  rc = sqlite3ApiExit(db, rc);
+  sqlite3_mutex_leave(db->mutex);
+  return rc;
+}
+
+#ifndef SQLITE_OMIT_UTF16
+EXPORT_C int sqlite3_create_function16(
+  sqlite3 *db,
+  const void *zFunctionName,
+  int nArg,
+  int eTextRep,
+  void *p,
+  void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
+  void (*xStep)(sqlite3_context*,int,sqlite3_value**),
+  void (*xFinal)(sqlite3_context*)
+){
+  int rc;
+  char *zFunc8;
+  sqlite3_mutex_enter(db->mutex);
+  assert( !db->mallocFailed );
+  zFunc8 = sqlite3Utf16to8(db, zFunctionName, -1);
+  rc = sqlite3CreateFunc(db, zFunc8, nArg, eTextRep, p, xFunc, xStep, xFinal);
+  sqlite3_free(zFunc8);
+  rc = sqlite3ApiExit(db, rc);
+  sqlite3_mutex_leave(db->mutex);
+  return rc;
+}
+#endif
+
+
+/*
+** Declare that a function has been overloaded by a virtual table.
+**
+** If the function already exists as a regular global function, then
+** this routine is a no-op.  If the function does not exist, then create
+** a new one that always throws a run-time error.  
+**
+** When virtual tables intend to provide an overloaded function, they
+** should call this routine to make sure the global function exists.
+** A global function must exist in order for name resolution to work
+** properly.
+*/
+EXPORT_C int sqlite3_overload_function(
+  sqlite3 *db,
+  const char *zName,
+  int nArg
+){
+  int nName = strlen(zName);
+  int rc;
+  sqlite3_mutex_enter(db->mutex);
+  if( sqlite3FindFunction(db, zName, nName, nArg, SQLITE_UTF8, 0)==0 ){
+    sqlite3CreateFunc(db, zName, nArg, SQLITE_UTF8,
+                      0, sqlite3InvalidFunction, 0, 0);
+  }
+  rc = sqlite3ApiExit(db, SQLITE_OK);
+  sqlite3_mutex_leave(db->mutex);
+  return rc;
+}
+
+#ifndef SQLITE_OMIT_TRACE
+/*
+** Register a trace function.  The pArg from the previously registered trace
+** is returned.  
+**
+** A NULL trace function means that no tracing is executes.  A non-NULL
+** trace is a pointer to a function that is invoked at the start of each
+** SQL statement.
+*/
+EXPORT_C void *sqlite3_trace(sqlite3 *db, void (*xTrace)(void*,const char*), void *pArg){
+  void *pOld;
+  sqlite3_mutex_enter(db->mutex);
+  pOld = db->pTraceArg;
+  db->xTrace = xTrace;
+  db->pTraceArg = pArg;
+  sqlite3_mutex_leave(db->mutex);
+  return pOld;
+}
+/*
+** Register a profile function.  The pArg from the previously registered 
+** profile function is returned.  
+**
+** A NULL profile function means that no profiling is executes.  A non-NULL
+** profile is a pointer to a function that is invoked at the conclusion of
+** each SQL statement that is run.
+*/
+EXPORT_C void *sqlite3_profile(
+  sqlite3 *db,
+  void (*xProfile)(void*,const char*,sqlite_uint64),
+  void *pArg
+){
+  void *pOld;
+  sqlite3_mutex_enter(db->mutex);
+  pOld = db->pProfileArg;
+  db->xProfile = xProfile;
+  db->pProfileArg = pArg;
+  sqlite3_mutex_leave(db->mutex);
+  return pOld;
+}
+#endif /* SQLITE_OMIT_TRACE */
+
+/*** EXPERIMENTAL ***
+**
+** Register a function to be invoked when a transaction comments.
+** If the invoked function returns non-zero, then the commit becomes a
+** rollback.
+*/
+EXPORT_C void *sqlite3_commit_hook(
+  sqlite3 *db,              /* Attach the hook to this database */
+  int (*xCallback)(void*),  /* Function to invoke on each commit */
+  void *pArg                /* Argument to the function */
+){
+  void *pOld;
+  sqlite3_mutex_enter(db->mutex);
+  pOld = db->pCommitArg;
+  db->xCommitCallback = xCallback;
+  db->pCommitArg = pArg;
+  sqlite3_mutex_leave(db->mutex);
+  return pOld;
+}
+
+/*
+** Register a callback to be invoked each time a row is updated,
+** inserted or deleted using this database connection.
+*/
+EXPORT_C void *sqlite3_update_hook(
+  sqlite3 *db,              /* Attach the hook to this database */
+  void (*xCallback)(void*,int,char const *,char const *,sqlite_int64),
+  void *pArg                /* Argument to the function */
+){
+  void *pRet;
+  sqlite3_mutex_enter(db->mutex);
+  pRet = db->pUpdateArg;
+  db->xUpdateCallback = xCallback;
+  db->pUpdateArg = pArg;
+  sqlite3_mutex_leave(db->mutex);
+  return pRet;
+}
+
+/*
+** Register a callback to be invoked each time a transaction is rolled
+** back by this database connection.
+*/
+EXPORT_C void *sqlite3_rollback_hook(
+  sqlite3 *db,              /* Attach the hook to this database */
+  void (*xCallback)(void*), /* Callback function */
+  void *pArg                /* Argument to the function */
+){
+  void *pRet;
+  sqlite3_mutex_enter(db->mutex);
+  pRet = db->pRollbackArg;
+  db->xRollbackCallback = xCallback;
+  db->pRollbackArg = pArg;
+  sqlite3_mutex_leave(db->mutex);
+  return pRet;
+}
+
+/*
+** This routine is called to create a connection to a database BTree
+** driver.  If zFilename is the name of a file, then that file is
+** opened and used.  If zFilename is the magic name ":memory:" then
+** the database is stored in memory (and is thus forgotten as soon as
+** the connection is closed.)  If zFilename is NULL then the database
+** is a "virtual" database for transient use only and is deleted as
+** soon as the connection is closed.
+**
+** A virtual database can be either a disk file (that is automatically
+** deleted when the file is closed) or it an be held entirely in memory,
+** depending on the values of the TEMP_STORE compile-time macro and the
+** db->temp_store variable, according to the following chart:
+**
+**       TEMP_STORE     db->temp_store     Location of temporary database
+**       ----------     --------------     ------------------------------
+**           0               any             file
+**           1                1              file
+**           1                2              memory
+**           1                0              file
+**           2                1              file
+**           2                2              memory
+**           2                0              memory
+**           3               any             memory
+*/
+int sqlite3BtreeFactory(
+  const sqlite3 *db,        /* Main database when opening aux otherwise 0 */
+  const char *zFilename,    /* Name of the file containing the BTree database */
+  int omitJournal,          /* if TRUE then do not journal this file */
+  int nCache,               /* How many pages in the page cache */
+  int vfsFlags,             /* Flags passed through to vfsOpen */
+  Btree **ppBtree           /* Pointer to new Btree object written here */
+){
+  int btFlags = 0;
+  int rc;
+  
+
+  assert( sqlite3_mutex_held(db->mutex) );
+  assert( ppBtree != 0);
+  
+
+  if( omitJournal ){
+    btFlags |= BTREE_OMIT_JOURNAL;
+  }
+  if( db->flags & SQLITE_NoReadlock ){
+    btFlags |= BTREE_NO_READLOCK;
+  }
+  if( zFilename==0 ){
+#if TEMP_STORE==0
+    /* Do nothing */
+#endif
+#ifndef SQLITE_OMIT_MEMORYDB
+#if TEMP_STORE==1
+    if( db->temp_store==2 ) zFilename = ":memory:";
+#endif
+#if TEMP_STORE==2
+    if( db->temp_store!=1 ) zFilename = ":memory:";
+#endif
+#if TEMP_STORE==3
+    zFilename = ":memory:";
+#endif
+#endif /* SQLITE_OMIT_MEMORYDB */
+  }
+
+  if( (vfsFlags & SQLITE_OPEN_MAIN_DB)!=0 && (zFilename==0 || *zFilename==0) ){
+    vfsFlags = (vfsFlags & ~SQLITE_OPEN_MAIN_DB) | SQLITE_OPEN_TEMP_DB;
+  }
+  rc = sqlite3BtreeOpen(zFilename, (sqlite3 *)db, ppBtree, btFlags, vfsFlags);
+
+  if( rc==SQLITE_OK ){
+    sqlite3BtreeSetCacheSize(*ppBtree, nCache);
+  }
+  return rc;
+}
+
+/*
+** Return UTF-8 encoded English language explanation of the most recent
+** error.
+*/
+EXPORT_C const char *sqlite3_errmsg(sqlite3 *db){
+  const char *z;
+  if( !db ){
+    return sqlite3ErrStr(SQLITE_NOMEM);
+  }
+  if( sqlite3SafetyCheck(db) || db->errCode==SQLITE_MISUSE ){
+    return sqlite3ErrStr(SQLITE_MISUSE);
+  }
+  sqlite3_mutex_enter(db->mutex);
+  assert( !db->mallocFailed );
+  z = (char*)sqlite3_value_text(db->pErr);
+  if( z==0 ){
+    z = sqlite3ErrStr(db->errCode);
+  }
+  sqlite3_mutex_leave(db->mutex);
+  return z;
+}
+
+#ifndef SQLITE_OMIT_UTF16
+/*
+** Return UTF-16 encoded English language explanation of the most recent
+** error.
+*/
+EXPORT_C const void *sqlite3_errmsg16(sqlite3 *db){
+  /* Because all the characters in the string are in the unicode
+  ** range 0x00-0xFF, if we pad the big-endian string with a 
+  ** zero byte, we can obtain the little-endian string with
+  ** &big_endian[1].
+  */
+  static const char outOfMemBe[] = {
+    0, 'o', 0, 'u', 0, 't', 0, ' ', 
+    0, 'o', 0, 'f', 0, ' ', 
+    0, 'm', 0, 'e', 0, 'm', 0, 'o', 0, 'r', 0, 'y', 0, 0, 0
+  };
+  static const char misuseBe [] = {
+    0, 'l', 0, 'i', 0, 'b', 0, 'r', 0, 'a', 0, 'r', 0, 'y', 0, ' ', 
+    0, 'r', 0, 'o', 0, 'u', 0, 't', 0, 'i', 0, 'n', 0, 'e', 0, ' ', 
+    0, 'c', 0, 'a', 0, 'l', 0, 'l', 0, 'e', 0, 'd', 0, ' ', 
+    0, 'o', 0, 'u', 0, 't', 0, ' ', 
+    0, 'o', 0, 'f', 0, ' ', 
+    0, 's', 0, 'e', 0, 'q', 0, 'u', 0, 'e', 0, 'n', 0, 'c', 0, 'e', 0, 0, 0
+  };
+
+  const void *z;
+  if( !db ){
+    return (void *)(&outOfMemBe[SQLITE_UTF16NATIVE==SQLITE_UTF16LE?1:0]);
+  }
+  if( sqlite3SafetyCheck(db) || db->errCode==SQLITE_MISUSE ){
+    return (void *)(&misuseBe[SQLITE_UTF16NATIVE==SQLITE_UTF16LE?1:0]);
+  }
+  sqlite3_mutex_enter(db->mutex);
+  assert( !db->mallocFailed );
+  z = sqlite3_value_text16(db->pErr);
+  if( z==0 ){
+    sqlite3ValueSetStr(db->pErr, -1, sqlite3ErrStr(db->errCode),
+         SQLITE_UTF8, SQLITE_STATIC);
+    z = sqlite3_value_text16(db->pErr);
+  }
+  sqlite3ApiExit(0, 0);
+  sqlite3_mutex_leave(db->mutex);
+  return z;
+}
+#endif /* SQLITE_OMIT_UTF16 */
+
+/*
+** Return the most recent error code generated by an SQLite routine. If NULL is
+** passed to this function, we assume a malloc() failed during sqlite3_open().
+*/
+EXPORT_C int sqlite3_errcode(sqlite3 *db){
+  if( !db || db->mallocFailed ){
+    return SQLITE_NOMEM;
+  }
+  if( sqlite3SafetyCheck(db) ){
+    return SQLITE_MISUSE;
+  }
+  return db->errCode & db->errMask;
+}
+
+/*
+** Create a new collating function for database "db".  The name is zName
+** and the encoding is enc.
+*/
+static int createCollation(
+  sqlite3* db, 
+  const char *zName, 
+  int enc, 
+  void* pCtx,
+  int(*xCompare)(void*,int,const void*,int,const void*),
+  void(*xDel)(void*)
+){
+  CollSeq *pColl;
+  int enc2;
+  
+  if( sqlite3SafetyCheck(db) ){
+    return SQLITE_MISUSE;
+  }
+  assert( sqlite3_mutex_held(db->mutex) );
+
+  /* If SQLITE_UTF16 is specified as the encoding type, transform this
+  ** to one of SQLITE_UTF16LE or SQLITE_UTF16BE using the
+  ** SQLITE_UTF16NATIVE macro. SQLITE_UTF16 is not used internally.
+  */
+  enc2 = enc & ~SQLITE_UTF16_ALIGNED;
+  if( enc2==SQLITE_UTF16 ){
+    enc2 = SQLITE_UTF16NATIVE;
+  }
+
+  if( (enc2&~3)!=0 ){
+    sqlite3Error(db, SQLITE_ERROR, "unknown encoding");
+    return SQLITE_ERROR;
+  }
+
+  /* Check if this call is removing or replacing an existing collation 
+  ** sequence. If so, and there are active VMs, return busy. If there
+  ** are no active VMs, invalidate any pre-compiled statements.
+  */
+  pColl = sqlite3FindCollSeq(db, (u8)enc2, zName, strlen(zName), 0);
+  if( pColl && pColl->xCmp ){
+    if( db->activeVdbeCnt ){
+      sqlite3Error(db, SQLITE_BUSY, 
+        "Unable to delete/modify collation sequence due to active statements");
+      return SQLITE_BUSY;
+    }
+    sqlite3ExpirePreparedStatements(db);
+
+    /* If collation sequence pColl was created directly by a call to
+    ** sqlite3_create_collation, and not generated by synthCollSeq(),
+    ** then any copies made by synthCollSeq() need to be invalidated.
+    ** Also, collation destructor - CollSeq.xDel() - function may need
+    ** to be called.
+    */ 
+    if( (pColl->enc & ~SQLITE_UTF16_ALIGNED)==enc2 ){
+      CollSeq *aColl = (CollSeq*)sqlite3HashFind(&db->aCollSeq, zName, strlen(zName));
+      int j;
+      for(j=0; j<3; j++){
+        CollSeq *p = &aColl[j];
+        if( p->enc==pColl->enc ){
+          if( p->xDel ){
+            p->xDel(p->pUser);
+          }
+          p->xCmp = 0;
+        }
+      }
+    }
+  }
+
+  pColl = sqlite3FindCollSeq(db, (u8)enc2, zName, strlen(zName), 1);
+  if( pColl ){
+    pColl->xCmp = xCompare;
+    pColl->pUser = pCtx;
+    pColl->xDel = xDel;
+    pColl->enc = enc2 | (enc & SQLITE_UTF16_ALIGNED);
+  }
+  sqlite3Error(db, SQLITE_OK, 0);
+  return SQLITE_OK;
+}
+
+FILE * fpLogFile = NULL;
+
+/*
+** This routine does the work of opening a database on behalf of
+** sqlite3_open() and sqlite3_open16(). The database filename "zFilename"  
+** is UTF-8 encoded.
+*/
+static int openDatabase(
+  const char *zFilename, /* Database filename UTF-8 encoded */
+  sqlite3 **ppDb,        /* OUT: Returned database handle */
+  unsigned flags,        /* Operational flags */
+  const char *zVfs       /* Name of the VFS to use */
+){
+  sqlite3 *db;
+  int rc;
+  CollSeq *pColl;
+
+
+  /* Allocate the sqlite data structure */
+  db = (sqlite3*)sqlite3MallocZero( sizeof(sqlite3) );
+  if( db==0 ) goto opendb_out;
+  db->mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_RECURSIVE);
+  if( db->mutex==0 ){
+    sqlite3_free(db);
+    db = 0;
+    goto opendb_out;
+  }
+  sqlite3_mutex_enter(db->mutex);
+  db->errMask = 0xff;
+  db->priorNewRowid = 0;
+  db->nDb = 2;
+  db->magic = SQLITE_MAGIC_BUSY;
+  db->aDb = db->aDbStatic;
+  db->autoCommit = 1;
+  db->nextAutovac = -1;
+  db->flags |= SQLITE_ShortColNames
+#if SQLITE_DEFAULT_FILE_FORMAT<4
+                 | SQLITE_LegacyFileFmt
+#endif
+#ifdef SQLITE_ENABLE_LOAD_EXTENSION
+                 | SQLITE_LoadExtension
+#endif
+      ;
+  sqlite3HashInit(&db->aFunc, SQLITE_HASH_STRING, 0);
+  sqlite3HashInit(&db->aCollSeq, SQLITE_HASH_STRING, 0);
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+  sqlite3HashInit(&db->aModule, SQLITE_HASH_STRING, 0);
+#endif
+
+  db->pVfs = sqlite3OsDefaultVfs();//sqlite3_vfs_find(zVfs);
+  if( !db->pVfs ){
+    rc = SQLITE_ERROR;
+    db->magic = SQLITE_MAGIC_CLOSED;
+    sqlite3Error(db, rc, "no such vfs: %s", (zVfs?zVfs:"(null)"));
+    goto opendb_out;
+  }
+
+  /* Add the default collation sequence BINARY. BINARY works for both UTF-8
+  ** and UTF-16, so add a version for each to avoid any unnecessary
+  ** conversions. The only error that can occur here is a malloc() failure.
+  */
+  if( createCollation(db, "BINARY", SQLITE_UTF8, 0, binCollFunc, 0) ||
+      createCollation(db, "BINARY", SQLITE_UTF16BE, 0, binCollFunc, 0) ||
+      createCollation(db, "BINARY", SQLITE_UTF16LE, 0, binCollFunc, 0) ||
+      (db->pDfltColl = sqlite3FindCollSeq(db, SQLITE_UTF8, "BINARY", 6, 0))==0 
+  ){
+    assert( db->mallocFailed );
+    db->magic = SQLITE_MAGIC_CLOSED;
+    goto opendb_out;
+  }
+
+  /* Also add a UTF-8 case-insensitive collation sequence. */
+  createCollation(db, "NOCASE", SQLITE_UTF8, 0, nocaseCollatingFunc, 0);
+
+  /* Set flags on the built-in collating sequences */
+  db->pDfltColl->type = SQLITE_COLL_BINARY;
+  pColl = sqlite3FindCollSeq(db, SQLITE_UTF8, "NOCASE", 6, 0);
+  if( pColl ){
+    pColl->type = SQLITE_COLL_NOCASE;
+  }
+
+  /* Open the backend database driver */
+  db->openFlags = flags;
+  rc = sqlite3BtreeFactory(db, zFilename, 0, SQLITE_DEFAULT_CACHE_SIZE, 
+                           flags | SQLITE_OPEN_MAIN_DB,
+                           &db->aDb[0].pBt);
+  if( rc!=SQLITE_OK ){
+    sqlite3Error(db, rc, 0);
+    db->magic = SQLITE_MAGIC_CLOSED;
+    goto opendb_out;
+  }
+  db->aDb[0].pSchema = sqlite3SchemaGet(db, db->aDb[0].pBt);
+  db->aDb[1].pSchema = sqlite3SchemaGet(db, 0);
+
+
+  /* The default safety_level for the main database is 'full'; for the temp
+  ** database it is 'NONE'. This matches the pager layer defaults.  
+  */
+  db->aDb[0].zName = "main";
+  db->aDb[0].safety_level = 3;
+#ifndef SQLITE_OMIT_TEMPDB
+  db->aDb[1].zName = "temp";
+  db->aDb[1].safety_level = 1;
+#endif
+
+  db->magic = SQLITE_MAGIC_OPEN;
+  if( db->mallocFailed ){
+    goto opendb_out;
+  }
+
+  /* Register all built-in functions, but do not attempt to read the
+  ** database schema yet. This is delayed until the first time the database
+  ** is accessed.
+  */
+  sqlite3Error(db, SQLITE_OK, 0);
+  sqlite3RegisterBuiltinFunctions(db);
+
+  /* Load automatic extensions - extensions that have been registered
+  ** using the sqlite3_automatic_extension() API.
+  */
+  (void)sqlite3AutoLoadExtensions(db);
+  if( sqlite3_errcode(db)!=SQLITE_OK ){
+    goto opendb_out;
+  }
+
+#ifdef SQLITE_ENABLE_FTS1
+  if( !db->mallocFailed ){
+    extern int sqlite3Fts1Init(sqlite3*);
+    rc = sqlite3Fts1Init(db);
+  }
+#endif
+
+#ifdef SQLITE_ENABLE_FTS2
+  if( !db->mallocFailed && rc==SQLITE_OK ){
+    extern int sqlite3Fts2Init(sqlite3*);
+    rc = sqlite3Fts2Init(db);
+  }
+#endif
+
+#ifdef SQLITE_ENABLE_FTS3
+  if( !db->mallocFailed && rc==SQLITE_OK ){
+    extern int sqlite3Fts3Init(sqlite3*);
+    rc = sqlite3Fts3Init(db);
+  }
+#endif
+
+#ifdef SQLITE_ENABLE_ICU
+  if( !db->mallocFailed && rc==SQLITE_OK ){
+    extern int sqlite3IcuInit(sqlite3*);
+    rc = sqlite3IcuInit(db);
+  }
+#endif
+  sqlite3Error(db, rc, 0);
+
+  /* -DSQLITE_DEFAULT_LOCKING_MODE=1 makes EXCLUSIVE the default locking
+  ** mode.  -DSQLITE_DEFAULT_LOCKING_MODE=0 make NORMAL the default locking
+  ** mode.  Doing nothing at all also makes NORMAL the default.
+  */
+#ifdef SQLITE_DEFAULT_LOCKING_MODE
+  db->dfltLockMode = SQLITE_DEFAULT_LOCKING_MODE;
+  sqlite3PagerLockingMode(sqlite3BtreePager(db->aDb[0].pBt),
+                          SQLITE_DEFAULT_LOCKING_MODE);
+#endif
+
+opendb_out:
+  if( db && db->mutex ){
+    sqlite3_mutex_leave(db->mutex);
+  }
+  if( SQLITE_NOMEM==(rc = sqlite3_errcode(db)) ){
+    sqlite3_close(db);
+    db = 0;
+  }
+  *ppDb = db;
+  return sqlite3ApiExit(0, rc);
+}
+
+/*
+** Open a new database handle.
+*/
+EXPORT_C int sqlite3_open(
+  const char *zFilename, 
+  sqlite3 **ppDb 
+){
+  return openDatabase(zFilename, ppDb,
+                      SQLITE_OPEN_READWRITE | SQLITE_OPEN_CREATE, 0);
+}
+
+EXPORT_C int sqlite3_open_v2(
+  const char *filename,   /* Database filename (UTF-8) */
+  sqlite3 **ppDb,         /* OUT: SQLite db handle */
+  int flags,              /* Flags */
+  const char *zVfs        /* Name of VFS module to use */
+){
+
+  return openDatabase(filename, ppDb, flags, zVfs);
+}
+
+#ifndef SQLITE_OMIT_UTF16
+/*
+** Open a new database handle.
+*/
+EXPORT_C int sqlite3_open16(
+  const void *zFilename, 
+  sqlite3 **ppDb
+){
+  char const *zFilename8;   /* zFilename encoded in UTF-8 instead of UTF-16 */
+  sqlite3_value *pVal;
+  int rc = SQLITE_NOMEM;
+
+  assert( zFilename );
+  assert( ppDb );
+  *ppDb = 0;
+  pVal = sqlite3ValueNew(0);
+  sqlite3ValueSetStr(pVal, -1, zFilename, SQLITE_UTF16NATIVE, SQLITE_STATIC);
+  zFilename8 = (const char*)sqlite3ValueText(pVal, SQLITE_UTF8);
+  if( zFilename8 ){
+    rc = openDatabase(zFilename8, ppDb,
+                      SQLITE_OPEN_READWRITE | SQLITE_OPEN_CREATE, 0);
+    if( rc==SQLITE_OK && *ppDb ){
+      rc = sqlite3_exec(*ppDb, "PRAGMA encoding = 'UTF-16'", 0, 0, 0);
+      if( rc!=SQLITE_OK ){
+        sqlite3_close(*ppDb);
+        *ppDb = 0;
+      }
+    }
+  }
+  sqlite3ValueFree(pVal);
+
+  return sqlite3ApiExit(0, rc);
+}
+#endif /* SQLITE_OMIT_UTF16 */
+
+/*
+** Register a new collation sequence with the database handle db.
+*/
+EXPORT_C int sqlite3_create_collation(
+  sqlite3* db, 
+  const char *zName, 
+  int enc, 
+  void* pCtx,
+  int(*xCompare)(void*,int,const void*,int,const void*)
+){
+  int rc;
+  sqlite3_mutex_enter(db->mutex);
+  assert( !db->mallocFailed );
+  rc = createCollation(db, zName, enc, pCtx, xCompare, 0);
+  rc = sqlite3ApiExit(db, rc);
+  sqlite3_mutex_leave(db->mutex);
+  return rc;
+}
+
+/*
+** Register a new collation sequence with the database handle db.
+*/
+EXPORT_C int sqlite3_create_collation_v2(
+  sqlite3* db, 
+  const char *zName, 
+  int enc, 
+  void* pCtx,
+  int(*xCompare)(void*,int,const void*,int,const void*),
+  void(*xDel)(void*)
+){
+  int rc;
+  sqlite3_mutex_enter(db->mutex);
+  assert( !db->mallocFailed );
+  rc = createCollation(db, zName, enc, pCtx, xCompare, xDel);
+  rc = sqlite3ApiExit(db, rc);
+  sqlite3_mutex_leave(db->mutex);
+  return rc;
+}
+
+#ifndef SQLITE_OMIT_UTF16
+/*
+** Register a new collation sequence with the database handle db.
+*/
+EXPORT_C int sqlite3_create_collation16(
+  sqlite3* db, 
+  const char *zName, 
+  int enc, 
+  void* pCtx,
+  int(*xCompare)(void*,int,const void*,int,const void*)
+){
+  int rc = SQLITE_OK;
+  char *zName8; 
+  sqlite3_mutex_enter(db->mutex);
+  assert( !db->mallocFailed );
+  zName8 = sqlite3Utf16to8(db, zName, -1);
+  if( zName8 ){
+    rc = createCollation(db, zName8, enc, pCtx, xCompare, 0);
+    sqlite3_free(zName8);
+  }
+  rc = sqlite3ApiExit(db, rc);
+  sqlite3_mutex_leave(db->mutex);
+  return rc;
+}
+#endif /* SQLITE_OMIT_UTF16 */
+
+/*
+** Register a collation sequence factory callback with the database handle
+** db. Replace any previously installed collation sequence factory.
+*/
+EXPORT_C int sqlite3_collation_needed(
+  sqlite3 *db, 
+  void *pCollNeededArg, 
+  void(*xCollNeeded)(void*,sqlite3*,int eTextRep,const char*)
+){
+  if( sqlite3SafetyCheck(db) ){
+    return SQLITE_MISUSE;
+  }
+  sqlite3_mutex_enter(db->mutex);
+  db->xCollNeeded = xCollNeeded;
+  db->xCollNeeded16 = 0;
+  db->pCollNeededArg = pCollNeededArg;
+  sqlite3_mutex_leave(db->mutex);
+  return SQLITE_OK;
+}
+
+#ifndef SQLITE_OMIT_UTF16
+/*
+** Register a collation sequence factory callback with the database handle
+** db. Replace any previously installed collation sequence factory.
+*/
+EXPORT_C int sqlite3_collation_needed16(
+  sqlite3 *db, 
+  void *pCollNeededArg, 
+  void(*xCollNeeded16)(void*,sqlite3*,int eTextRep,const void*)
+){
+  if( sqlite3SafetyCheck(db) ){
+    return SQLITE_MISUSE;
+  }
+  sqlite3_mutex_enter(db->mutex);
+  db->xCollNeeded = 0;
+  db->xCollNeeded16 = xCollNeeded16;
+  db->pCollNeededArg = pCollNeededArg;
+  sqlite3_mutex_leave(db->mutex);
+  return SQLITE_OK;
+}
+#endif /* SQLITE_OMIT_UTF16 */
+
+#ifndef SQLITE_OMIT_GLOBALRECOVER
+/*
+** This function is now an anachronism. It used to be used to recover from a
+** malloc() failure, but SQLite now does this automatically.
+*/
+EXPORT_C int sqlite3_global_recover(void){
+  return SQLITE_OK;
+}
+#endif
+
+/*
+** Test to see whether or not the database connection is in autocommit
+** mode.  Return TRUE if it is and FALSE if not.  Autocommit mode is on
+** by default.  Autocommit is disabled by a BEGIN statement and reenabled
+** by the next COMMIT or ROLLBACK.
+**
+******* THIS IS AN EXPERIMENTAL API AND IS SUBJECT TO CHANGE ******
+*/
+EXPORT_C int sqlite3_get_autocommit(sqlite3 *db){
+  return db->autoCommit;
+}
+
+#ifdef SQLITE_DEBUG
+/*
+** The following routine is subtituted for constant SQLITE_CORRUPT in
+** debugging builds.  This provides a way to set a breakpoint for when
+** corruption is first detected.
+*/
+int sqlite3Corrupt(void){
+  return SQLITE_CORRUPT;
+}
+#endif
+
+/*
+** This is a convenience routine that makes sure that all thread-specific
+** data for this thread has been deallocated.
+**
+** SQLite no longer uses thread-specific data so this routine is now a
+** no-op.  It is retained for historical compatibility.
+*/
+EXPORT_C void sqlite3_thread_cleanup(void){
+}
+
+/*
+** Return meta information about a specific column of a database table.
+** See comment in sqlite3.h (sqlite.h.in) for details.
+*/
+#ifdef SQLITE_ENABLE_COLUMN_METADATA
+int sqlite3_table_column_metadata(
+  sqlite3 *db,                /* Connection handle */
+  const char *zDbName,        /* Database name or NULL */
+  const char *zTableName,     /* Table name */
+  const char *zColumnName,    /* Column name */
+  char const **pzDataType,    /* OUTPUT: Declared data type */
+  char const **pzCollSeq,     /* OUTPUT: Collation sequence name */
+  int *pNotNull,              /* OUTPUT: True if NOT NULL constraint exists */
+  int *pPrimaryKey,           /* OUTPUT: True if column part of PK */
+  int *pAutoinc               /* OUTPUT: True if colums is auto-increment */
+){
+  int rc;
+  char *zErrMsg = 0;
+  Table *pTab = 0;
+  Column *pCol = 0;
+  int iCol;
+
+  char const *zDataType = 0;
+  char const *zCollSeq = 0;
+  int notnull = 0;
+  int primarykey = 0;
+  int autoinc = 0;
+
+  /* Ensure the database schema has been loaded */
+  if( sqlite3SafetyOn(db) ){
+    return SQLITE_MISUSE;
+  }
+  sqlite3_mutex_enter(db->mutex);
+  rc = sqlite3Init(db, &zErrMsg);
+  if( SQLITE_OK!=rc ){
+    goto error_out;
+  }
+
+  /* Locate the table in question */
+  pTab = sqlite3FindTable(db, zTableName, zDbName);
+  if( !pTab || pTab->pSelect ){
+    pTab = 0;
+    goto error_out;
+  }
+
+  /* Find the column for which info is requested */
+  if( sqlite3IsRowid(zColumnName) ){
+    iCol = pTab->iPKey;
+    if( iCol>=0 ){
+      pCol = &pTab->aCol[iCol];
+    }
+  }else{
+    for(iCol=0; iCol<pTab->nCol; iCol++){
+      pCol = &pTab->aCol[iCol];
+      if( 0==sqlite3StrICmp(pCol->zName, zColumnName) ){
+        break;
+      }
+    }
+    if( iCol==pTab->nCol ){
+      pTab = 0;
+      goto error_out;
+    }
+  }
+
+  /* The following block stores the meta information that will be returned
+  ** to the caller in local variables zDataType, zCollSeq, notnull, primarykey
+  ** and autoinc. At this point there are two possibilities:
+  ** 
+  **     1. The specified column name was rowid", "oid" or "_rowid_" 
+  **        and there is no explicitly declared IPK column. 
+  **
+  **     2. The table is not a view and the column name identified an 
+  **        explicitly declared column. Copy meta information from *pCol.
+  */ 
+  if( pCol ){
+    zDataType = pCol->zType;
+    zCollSeq = pCol->zColl;
+    notnull = (pCol->notNull?1:0);
+    primarykey  = (pCol->isPrimKey?1:0);
+    autoinc = ((pTab->iPKey==iCol && pTab->autoInc)?1:0);
+  }else{
+    zDataType = "INTEGER";
+    primarykey = 1;
+  }
+  if( !zCollSeq ){
+    zCollSeq = "BINARY";
+  }
+
+error_out:
+  if( sqlite3SafetyOff(db) ){
+    rc = SQLITE_MISUSE;
+  }
+
+  /* Whether the function call succeeded or failed, set the output parameters
+  ** to whatever their local counterparts contain. If an error did occur,
+  ** this has the effect of zeroing all output parameters.
+  */
+  if( pzDataType ) *pzDataType = zDataType;
+  if( pzCollSeq ) *pzCollSeq = zCollSeq;
+  if( pNotNull ) *pNotNull = notnull;
+  if( pPrimaryKey ) *pPrimaryKey = primarykey;
+  if( pAutoinc ) *pAutoinc = autoinc;
+
+  if( SQLITE_OK==rc && !pTab ){
+    sqlite3SetString(&zErrMsg, "no such table column: ", zTableName, ".", 
+        zColumnName, 0);
+    rc = SQLITE_ERROR;
+  }
+  sqlite3Error(db, rc, (zErrMsg?"%s":0), zErrMsg);
+  sqlite3_free(zErrMsg);
+  rc = sqlite3ApiExit(db, rc);
+  sqlite3_mutex_leave(db->mutex);
+  return rc;
+}
+#endif
+
+/*
+** Sleep for a little while.  Return the amount of time slept.
+*/
+EXPORT_C int sqlite3_sleep(int ms){
+  sqlite3_vfs *pVfs;
+  int rc;
+  pVfs = sqlite3_vfs_find(0);
+
+  /* This function works in milliseconds, but the underlying OsSleep() 
+  ** API uses microseconds. Hence the 1000's.
+  */
+  rc = (sqlite3OsSleep(pVfs, 1000*ms)/1000);
+  return rc;
+}
+
+/*
+** Enable or disable the extended result codes.
+*/
+EXPORT_C int sqlite3_extended_result_codes(sqlite3 *db, int onoff){
+  sqlite3_mutex_enter(db->mutex);
+  db->errMask = onoff ? 0xffffffff : 0xff;
+  sqlite3_mutex_leave(db->mutex);
+  return SQLITE_OK;
+}
+
+/*
+** Invoke the xFileControl method on a particular database.
+*/
+EXPORT_C int sqlite3_file_control(sqlite3 *db, const char *zDbName, int op, void *pArg){
+  int rc = SQLITE_ERROR;
+  int iDb;
+  sqlite3_mutex_enter(db->mutex);
+  if( zDbName==0 ){
+    iDb = 0;
+  }else{
+    for(iDb=0; iDb<db->nDb; iDb++){
+      if( strcmp(db->aDb[iDb].zName, zDbName)==0 ) break;
+    }
+  }
+  if( iDb<db->nDb ){
+    Btree *pBtree = db->aDb[iDb].pBt;
+    if( pBtree ){
+      Pager *pPager;
+      sqlite3BtreeEnter(pBtree);
+      pPager = sqlite3BtreePager(pBtree);
+      if( pPager ){
+        sqlite3_file *fd = sqlite3PagerFile(pPager);
+        if( fd ){
+          rc = sqlite3OsFileControl(fd, op, pArg);
+        }
+      }
+      sqlite3BtreeLeave(pBtree);
+    }
+  }
+  sqlite3_mutex_leave(db->mutex);
+  return rc;   
+}