sourcemod/extensions/sqlite/sqlite-source/prepare.c
Scott Ehlert 251cced1f8 Spring Cleaning, Part Ichi (1)
Various minor things done to project files
Updated sample extension project file and updated makefile to the new unified version (more changes likely on the way)
Updated regex project file and makefile

--HG--
extra : convert_revision : svn%3A39bc706e-5318-0410-9160-8a85361fbb7c/trunk%401971
2008-03-30 07:00:22 +00:00

743 lines
23 KiB
C

/*
** 2005 May 25
**
** The author disclaims copyright to this source code. In place of
** a legal notice, here is a blessing:
**
** May you do good and not evil.
** May you find forgiveness for yourself and forgive others.
** May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains the implementation of the sqlite3_prepare()
** interface, and routines that contribute to loading the database schema
** from disk.
**
** $Id$
*/
#include "sqliteInt.h"
#include <ctype.h>
/*
** Fill the InitData structure with an error message that indicates
** that the database is corrupt.
*/
static void corruptSchema(InitData *pData, const char *zExtra){
if( !pData->db->mallocFailed ){
sqlite3SetString(pData->pzErrMsg, "malformed database schema",
zExtra!=0 && zExtra[0]!=0 ? " - " : (char*)0, zExtra, (char*)0);
}
pData->rc = SQLITE_CORRUPT;
}
/*
** This is the callback routine for the code that initializes the
** database. See sqlite3Init() below for additional information.
** This routine is also called from the OP_ParseSchema opcode of the VDBE.
**
** Each callback contains the following information:
**
** argv[0] = name of thing being created
** argv[1] = root page number for table or index. 0 for trigger or view.
** argv[2] = SQL text for the CREATE statement.
**
*/
int sqlite3InitCallback(void *pInit, int argc, char **argv, char **azColName){
InitData *pData = (InitData*)pInit;
sqlite3 *db = pData->db;
int iDb = pData->iDb;
assert( sqlite3_mutex_held(db->mutex) );
pData->rc = SQLITE_OK;
DbClearProperty(db, iDb, DB_Empty);
if( db->mallocFailed ){
corruptSchema(pData, 0);
return SQLITE_NOMEM;
}
assert( argc==3 );
if( argv==0 ) return 0; /* Might happen if EMPTY_RESULT_CALLBACKS are on */
if( argv[1]==0 ){
corruptSchema(pData, 0);
return 1;
}
assert( iDb>=0 && iDb<db->nDb );
if( argv[2] && argv[2][0] ){
/* Call the parser to process a CREATE TABLE, INDEX or VIEW.
** But because db->init.busy is set to 1, no VDBE code is generated
** or executed. All the parser does is build the internal data
** structures that describe the table, index, or view.
*/
char *zErr;
int rc;
assert( db->init.busy );
db->init.iDb = iDb;
db->init.newTnum = atoi(argv[1]);
rc = sqlite3_exec(db, argv[2], 0, 0, &zErr);
db->init.iDb = 0;
assert( rc!=SQLITE_OK || zErr==0 );
if( SQLITE_OK!=rc ){
pData->rc = rc;
if( rc==SQLITE_NOMEM ){
db->mallocFailed = 1;
}else if( rc!=SQLITE_INTERRUPT ){
corruptSchema(pData, zErr);
}
sqlite3_free(zErr);
return 1;
}
}else{
/* If the SQL column is blank it means this is an index that
** was created to be the PRIMARY KEY or to fulfill a UNIQUE
** constraint for a CREATE TABLE. The index should have already
** been created when we processed the CREATE TABLE. All we have
** to do here is record the root page number for that index.
*/
Index *pIndex;
pIndex = sqlite3FindIndex(db, argv[0], db->aDb[iDb].zName);
if( pIndex==0 || pIndex->tnum!=0 ){
/* This can occur if there exists an index on a TEMP table which
** has the same name as another index on a permanent index. Since
** the permanent table is hidden by the TEMP table, we can also
** safely ignore the index on the permanent table.
*/
/* Do Nothing */;
}else{
pIndex->tnum = atoi(argv[1]);
}
}
return 0;
}
/*
** Attempt to read the database schema and initialize internal
** data structures for a single database file. The index of the
** database file is given by iDb. iDb==0 is used for the main
** database. iDb==1 should never be used. iDb>=2 is used for
** auxiliary databases. Return one of the SQLITE_ error codes to
** indicate success or failure.
*/
static int sqlite3InitOne(sqlite3 *db, int iDb, char **pzErrMsg){
int rc;
BtCursor *curMain;
int size;
Table *pTab;
Db *pDb;
char const *azArg[4];
int meta[10];
InitData initData;
char const *zMasterSchema;
char const *zMasterName = SCHEMA_TABLE(iDb);
/*
** The master database table has a structure like this
*/
static const char master_schema[] =
"CREATE TABLE sqlite_master(\n"
" type text,\n"
" name text,\n"
" tbl_name text,\n"
" rootpage integer,\n"
" sql text\n"
")"
;
#ifndef SQLITE_OMIT_TEMPDB
static const char temp_master_schema[] =
"CREATE TEMP TABLE sqlite_temp_master(\n"
" type text,\n"
" name text,\n"
" tbl_name text,\n"
" rootpage integer,\n"
" sql text\n"
")"
;
#else
#define temp_master_schema 0
#endif
assert( iDb>=0 && iDb<db->nDb );
assert( db->aDb[iDb].pSchema );
assert( sqlite3_mutex_held(db->mutex) );
/* zMasterSchema and zInitScript are set to point at the master schema
** and initialisation script appropriate for the database being
** initialised. zMasterName is the name of the master table.
*/
if( !OMIT_TEMPDB && iDb==1 ){
zMasterSchema = temp_master_schema;
}else{
zMasterSchema = master_schema;
}
zMasterName = SCHEMA_TABLE(iDb);
/* Construct the schema tables. */
sqlite3SafetyOff(db);
azArg[0] = zMasterName;
azArg[1] = "1";
azArg[2] = zMasterSchema;
azArg[3] = 0;
initData.db = db;
initData.iDb = iDb;
initData.pzErrMsg = pzErrMsg;
rc = sqlite3InitCallback(&initData, 3, (char **)azArg, 0);
if( rc ){
sqlite3SafetyOn(db);
rc = initData.rc;
goto error_out;
}
pTab = sqlite3FindTable(db, zMasterName, db->aDb[iDb].zName);
if( pTab ){
pTab->readOnly = 1;
}
sqlite3SafetyOn(db);
/* Create a cursor to hold the database open
*/
pDb = &db->aDb[iDb];
if( pDb->pBt==0 ){
if( !OMIT_TEMPDB && iDb==1 ){
DbSetProperty(db, 1, DB_SchemaLoaded);
}
return SQLITE_OK;
}
sqlite3BtreeEnter(pDb->pBt);
rc = sqlite3BtreeCursor(pDb->pBt, MASTER_ROOT, 0, 0, 0, &curMain);
if( rc!=SQLITE_OK && rc!=SQLITE_EMPTY ){
sqlite3SetString(pzErrMsg, sqlite3ErrStr(rc), (char*)0);
sqlite3BtreeLeave(pDb->pBt);
goto error_out;
}
/* Get the database meta information.
**
** Meta values are as follows:
** meta[0] Schema cookie. Changes with each schema change.
** meta[1] File format of schema layer.
** meta[2] Size of the page cache.
** meta[3] Use freelist if 0. Autovacuum if greater than zero.
** meta[4] Db text encoding. 1:UTF-8 2:UTF-16LE 3:UTF-16BE
** meta[5] The user cookie. Used by the application.
** meta[6] Incremental-vacuum flag.
** meta[7]
** meta[8]
** meta[9]
**
** Note: The #defined SQLITE_UTF* symbols in sqliteInt.h correspond to
** the possible values of meta[4].
*/
if( rc==SQLITE_OK ){
int i;
for(i=0; rc==SQLITE_OK && i<sizeof(meta)/sizeof(meta[0]); i++){
rc = sqlite3BtreeGetMeta(pDb->pBt, i+1, (u32 *)&meta[i]);
}
if( rc ){
sqlite3SetString(pzErrMsg, sqlite3ErrStr(rc), (char*)0);
sqlite3BtreeCloseCursor(curMain);
sqlite3BtreeLeave(pDb->pBt);
goto error_out;
}
}else{
memset(meta, 0, sizeof(meta));
}
pDb->pSchema->schema_cookie = meta[0];
/* If opening a non-empty database, check the text encoding. For the
** main database, set sqlite3.enc to the encoding of the main database.
** For an attached db, it is an error if the encoding is not the same
** as sqlite3.enc.
*/
if( meta[4] ){ /* text encoding */
if( iDb==0 ){
/* If opening the main database, set ENC(db). */
ENC(db) = (u8)meta[4];
db->pDfltColl = sqlite3FindCollSeq(db, SQLITE_UTF8, "BINARY", 6, 0);
}else{
/* If opening an attached database, the encoding much match ENC(db) */
if( meta[4]!=ENC(db) ){
sqlite3BtreeCloseCursor(curMain);
sqlite3SetString(pzErrMsg, "attached databases must use the same"
" text encoding as main database", (char*)0);
sqlite3BtreeLeave(pDb->pBt);
return SQLITE_ERROR;
}
}
}else{
DbSetProperty(db, iDb, DB_Empty);
}
pDb->pSchema->enc = ENC(db);
size = meta[2];
if( size==0 ){ size = SQLITE_DEFAULT_CACHE_SIZE; }
pDb->pSchema->cache_size = size;
sqlite3BtreeSetCacheSize(pDb->pBt, pDb->pSchema->cache_size);
/*
** file_format==1 Version 3.0.0.
** file_format==2 Version 3.1.3. // ALTER TABLE ADD COLUMN
** file_format==3 Version 3.1.4. // ditto but with non-NULL defaults
** file_format==4 Version 3.3.0. // DESC indices. Boolean constants
*/
pDb->pSchema->file_format = meta[1];
if( pDb->pSchema->file_format==0 ){
pDb->pSchema->file_format = 1;
}
if( pDb->pSchema->file_format>SQLITE_MAX_FILE_FORMAT ){
sqlite3BtreeCloseCursor(curMain);
sqlite3SetString(pzErrMsg, "unsupported file format", (char*)0);
sqlite3BtreeLeave(pDb->pBt);
return SQLITE_ERROR;
}
/* Read the schema information out of the schema tables
*/
assert( db->init.busy );
if( rc==SQLITE_EMPTY ){
/* For an empty database, there is nothing to read */
rc = SQLITE_OK;
}else{
char *zSql;
zSql = sqlite3MPrintf(db,
"SELECT name, rootpage, sql FROM '%q'.%s",
db->aDb[iDb].zName, zMasterName);
sqlite3SafetyOff(db);
rc = sqlite3_exec(db, zSql, sqlite3InitCallback, &initData, 0);
if( rc==SQLITE_ABORT ) rc = initData.rc;
sqlite3SafetyOn(db);
sqlite3_free(zSql);
#ifndef SQLITE_OMIT_ANALYZE
if( rc==SQLITE_OK ){
sqlite3AnalysisLoad(db, iDb);
}
#endif
sqlite3BtreeCloseCursor(curMain);
}
if( db->mallocFailed ){
/* sqlite3SetString(pzErrMsg, "out of memory", (char*)0); */
rc = SQLITE_NOMEM;
sqlite3ResetInternalSchema(db, 0);
}
if( rc==SQLITE_OK || (db->flags&SQLITE_RecoveryMode)){
/* Black magic: If the SQLITE_RecoveryMode flag is set, then consider
** the schema loaded, even if errors occured. In this situation the
** current sqlite3_prepare() operation will fail, but the following one
** will attempt to compile the supplied statement against whatever subset
** of the schema was loaded before the error occured. The primary
** purpose of this is to allow access to the sqlite_master table
** even when it's contents have been corrupted.
*/
DbSetProperty(db, iDb, DB_SchemaLoaded);
rc = SQLITE_OK;
}
sqlite3BtreeLeave(pDb->pBt);
error_out:
if( rc==SQLITE_NOMEM || rc==SQLITE_IOERR_NOMEM ){
db->mallocFailed = 1;
}
return rc;
}
/*
** Initialize all database files - the main database file, the file
** used to store temporary tables, and any additional database files
** created using ATTACH statements. Return a success code. If an
** error occurs, write an error message into *pzErrMsg.
**
** After a database is initialized, the DB_SchemaLoaded bit is set
** bit is set in the flags field of the Db structure. If the database
** file was of zero-length, then the DB_Empty flag is also set.
*/
int sqlite3Init(sqlite3 *db, char **pzErrMsg){
int i, rc;
int commit_internal = !(db->flags&SQLITE_InternChanges);
assert( sqlite3_mutex_held(db->mutex) );
if( db->init.busy ) return SQLITE_OK;
rc = SQLITE_OK;
db->init.busy = 1;
for(i=0; rc==SQLITE_OK && i<db->nDb; i++){
if( DbHasProperty(db, i, DB_SchemaLoaded) || i==1 ) continue;
rc = sqlite3InitOne(db, i, pzErrMsg);
if( rc ){
sqlite3ResetInternalSchema(db, i);
}
}
/* Once all the other databases have been initialised, load the schema
** for the TEMP database. This is loaded last, as the TEMP database
** schema may contain references to objects in other databases.
*/
#ifndef SQLITE_OMIT_TEMPDB
if( rc==SQLITE_OK && db->nDb>1 && !DbHasProperty(db, 1, DB_SchemaLoaded) ){
rc = sqlite3InitOne(db, 1, pzErrMsg);
if( rc ){
sqlite3ResetInternalSchema(db, 1);
}
}
#endif
db->init.busy = 0;
if( rc==SQLITE_OK && commit_internal ){
sqlite3CommitInternalChanges(db);
}
return rc;
}
/*
** This routine is a no-op if the database schema is already initialised.
** Otherwise, the schema is loaded. An error code is returned.
*/
int sqlite3ReadSchema(Parse *pParse){
int rc = SQLITE_OK;
sqlite3 *db = pParse->db;
assert( sqlite3_mutex_held(db->mutex) );
if( !db->init.busy ){
rc = sqlite3Init(db, &pParse->zErrMsg);
}
if( rc!=SQLITE_OK ){
pParse->rc = rc;
pParse->nErr++;
}
return rc;
}
/*
** Check schema cookies in all databases. If any cookie is out
** of date, return 0. If all schema cookies are current, return 1.
*/
static int schemaIsValid(sqlite3 *db){
int iDb;
int rc;
BtCursor *curTemp;
int cookie;
int allOk = 1;
assert( sqlite3_mutex_held(db->mutex) );
for(iDb=0; allOk && iDb<db->nDb; iDb++){
Btree *pBt;
pBt = db->aDb[iDb].pBt;
if( pBt==0 ) continue;
rc = sqlite3BtreeCursor(pBt, MASTER_ROOT, 0, 0, 0, &curTemp);
if( rc==SQLITE_OK ){
rc = sqlite3BtreeGetMeta(pBt, 1, (u32 *)&cookie);
if( rc==SQLITE_OK && cookie!=db->aDb[iDb].pSchema->schema_cookie ){
allOk = 0;
}
sqlite3BtreeCloseCursor(curTemp);
}
if( rc==SQLITE_NOMEM || rc==SQLITE_IOERR_NOMEM ){
db->mallocFailed = 1;
}
}
return allOk;
}
/*
** Convert a schema pointer into the iDb index that indicates
** which database file in db->aDb[] the schema refers to.
**
** If the same database is attached more than once, the first
** attached database is returned.
*/
int sqlite3SchemaToIndex(sqlite3 *db, Schema *pSchema){
int i = -1000000;
/* If pSchema is NULL, then return -1000000. This happens when code in
** expr.c is trying to resolve a reference to a transient table (i.e. one
** created by a sub-select). In this case the return value of this
** function should never be used.
**
** We return -1000000 instead of the more usual -1 simply because using
** -1000000 as incorrectly using -1000000 index into db->aDb[] is much
** more likely to cause a segfault than -1 (of course there are assert()
** statements too, but it never hurts to play the odds).
*/
assert( sqlite3_mutex_held(db->mutex) );
if( pSchema ){
for(i=0; i<db->nDb; i++){
if( db->aDb[i].pSchema==pSchema ){
break;
}
}
assert( i>=0 &&i>=0 && i<db->nDb );
}
return i;
}
/*
** Compile the UTF-8 encoded SQL statement zSql into a statement handle.
*/
int sqlite3Prepare(
sqlite3 *db, /* Database handle. */
const char *zSql, /* UTF-8 encoded SQL statement. */
int nBytes, /* Length of zSql in bytes. */
int saveSqlFlag, /* True to copy SQL text into the sqlite3_stmt */
sqlite3_stmt **ppStmt, /* OUT: A pointer to the prepared statement */
const char **pzTail /* OUT: End of parsed string */
){
Parse sParse;
char *zErrMsg = 0;
int rc = SQLITE_OK;
int i;
assert( ppStmt );
*ppStmt = 0;
if( sqlite3SafetyOn(db) ){
return SQLITE_MISUSE;
}
assert( !db->mallocFailed );
assert( sqlite3_mutex_held(db->mutex) );
/* If any attached database schemas are locked, do not proceed with
** compilation. Instead return SQLITE_LOCKED immediately.
*/
for(i=0; i<db->nDb; i++) {
Btree *pBt = db->aDb[i].pBt;
if( pBt ){
int rc;
rc = sqlite3BtreeSchemaLocked(pBt);
if( rc ){
const char *zDb = db->aDb[i].zName;
sqlite3Error(db, SQLITE_LOCKED, "database schema is locked: %s", zDb);
sqlite3SafetyOff(db);
return SQLITE_LOCKED;
}
}
}
memset(&sParse, 0, sizeof(sParse));
sParse.db = db;
if( nBytes>=0 && zSql[nBytes]!=0 ){
char *zSqlCopy;
if( nBytes>SQLITE_MAX_SQL_LENGTH ){
return SQLITE_TOOBIG;
}
zSqlCopy = sqlite3DbStrNDup(db, zSql, nBytes);
if( zSqlCopy ){
sqlite3RunParser(&sParse, zSqlCopy, &zErrMsg);
sqlite3_free(zSqlCopy);
}
sParse.zTail = &zSql[nBytes];
}else{
sqlite3RunParser(&sParse, zSql, &zErrMsg);
}
if( db->mallocFailed ){
sParse.rc = SQLITE_NOMEM;
}
if( sParse.rc==SQLITE_DONE ) sParse.rc = SQLITE_OK;
if( sParse.checkSchema && !schemaIsValid(db) ){
sParse.rc = SQLITE_SCHEMA;
}
if( sParse.rc==SQLITE_SCHEMA ){
sqlite3ResetInternalSchema(db, 0);
}
if( db->mallocFailed ){
sParse.rc = SQLITE_NOMEM;
}
if( pzTail ){
*pzTail = sParse.zTail;
}
rc = sParse.rc;
#ifndef SQLITE_OMIT_EXPLAIN
if( rc==SQLITE_OK && sParse.pVdbe && sParse.explain ){
if( sParse.explain==2 ){
sqlite3VdbeSetNumCols(sParse.pVdbe, 3);
sqlite3VdbeSetColName(sParse.pVdbe, 0, COLNAME_NAME, "order", P3_STATIC);
sqlite3VdbeSetColName(sParse.pVdbe, 1, COLNAME_NAME, "from", P3_STATIC);
sqlite3VdbeSetColName(sParse.pVdbe, 2, COLNAME_NAME, "detail", P3_STATIC);
}else{
sqlite3VdbeSetNumCols(sParse.pVdbe, 5);
sqlite3VdbeSetColName(sParse.pVdbe, 0, COLNAME_NAME, "addr", P3_STATIC);
sqlite3VdbeSetColName(sParse.pVdbe, 1, COLNAME_NAME, "opcode", P3_STATIC);
sqlite3VdbeSetColName(sParse.pVdbe, 2, COLNAME_NAME, "p1", P3_STATIC);
sqlite3VdbeSetColName(sParse.pVdbe, 3, COLNAME_NAME, "p2", P3_STATIC);
sqlite3VdbeSetColName(sParse.pVdbe, 4, COLNAME_NAME, "p3", P3_STATIC);
}
}
#endif
if( sqlite3SafetyOff(db) ){
rc = SQLITE_MISUSE;
}
if( saveSqlFlag ){
sqlite3VdbeSetSql(sParse.pVdbe, zSql, sParse.zTail - zSql);
}
if( rc!=SQLITE_OK || db->mallocFailed ){
sqlite3_finalize((sqlite3_stmt*)sParse.pVdbe);
assert(!(*ppStmt));
}else{
*ppStmt = (sqlite3_stmt*)sParse.pVdbe;
}
if( zErrMsg ){
sqlite3Error(db, rc, "%s", zErrMsg);
sqlite3_free(zErrMsg);
}else{
sqlite3Error(db, rc, 0);
}
rc = sqlite3ApiExit(db, rc);
/* sqlite3ReleaseThreadData(); */
assert( (rc&db->errMask)==rc );
return rc;
}
static int sqlite3LockAndPrepare(
sqlite3 *db, /* Database handle. */
const char *zSql, /* UTF-8 encoded SQL statement. */
int nBytes, /* Length of zSql in bytes. */
int saveSqlFlag, /* True to copy SQL text into the sqlite3_stmt */
sqlite3_stmt **ppStmt, /* OUT: A pointer to the prepared statement */
const char **pzTail /* OUT: End of parsed string */
){
int rc;
if( sqlite3SafetyCheck(db) ){
return SQLITE_MISUSE;
}
sqlite3_mutex_enter(db->mutex);
sqlite3BtreeEnterAll(db);
rc = sqlite3Prepare(db, zSql, nBytes, saveSqlFlag, ppStmt, pzTail);
sqlite3BtreeLeaveAll(db);
sqlite3_mutex_leave(db->mutex);
return rc;
}
/*
** Rerun the compilation of a statement after a schema change.
** Return true if the statement was recompiled successfully.
** Return false if there is an error of some kind.
*/
int sqlite3Reprepare(Vdbe *p){
int rc;
sqlite3_stmt *pNew;
const char *zSql;
sqlite3 *db;
assert( sqlite3_mutex_held(sqlite3VdbeDb(p)->mutex) );
zSql = sqlite3VdbeGetSql(p);
if( zSql==0 ){
return 0;
}
db = sqlite3VdbeDb(p);
assert( sqlite3_mutex_held(db->mutex) );
rc = sqlite3LockAndPrepare(db, zSql, -1, 0, &pNew, 0);
if( rc ){
assert( pNew==0 );
return 0;
}else{
assert( pNew!=0 );
}
sqlite3VdbeSwap((Vdbe*)pNew, p);
sqlite3_transfer_bindings(pNew, (sqlite3_stmt*)p);
sqlite3VdbeResetStepResult((Vdbe*)pNew);
sqlite3VdbeFinalize((Vdbe*)pNew);
return 1;
}
/*
** Two versions of the official API. Legacy and new use. In the legacy
** version, the original SQL text is not saved in the prepared statement
** and so if a schema change occurs, SQLITE_SCHEMA is returned by
** sqlite3_step(). In the new version, the original SQL text is retained
** and the statement is automatically recompiled if an schema change
** occurs.
*/
int sqlite3_prepare(
sqlite3 *db, /* Database handle. */
const char *zSql, /* UTF-8 encoded SQL statement. */
int nBytes, /* Length of zSql in bytes. */
sqlite3_stmt **ppStmt, /* OUT: A pointer to the prepared statement */
const char **pzTail /* OUT: End of parsed string */
){
return sqlite3LockAndPrepare(db,zSql,nBytes,0,ppStmt,pzTail);
}
int sqlite3_prepare_v2(
sqlite3 *db, /* Database handle. */
const char *zSql, /* UTF-8 encoded SQL statement. */
int nBytes, /* Length of zSql in bytes. */
sqlite3_stmt **ppStmt, /* OUT: A pointer to the prepared statement */
const char **pzTail /* OUT: End of parsed string */
){
return sqlite3LockAndPrepare(db,zSql,nBytes,1,ppStmt,pzTail);
}
#ifndef SQLITE_OMIT_UTF16
/*
** Compile the UTF-16 encoded SQL statement zSql into a statement handle.
*/
static int sqlite3Prepare16(
sqlite3 *db, /* Database handle. */
const void *zSql, /* UTF-8 encoded SQL statement. */
int nBytes, /* Length of zSql in bytes. */
int saveSqlFlag, /* True to save SQL text into the sqlite3_stmt */
sqlite3_stmt **ppStmt, /* OUT: A pointer to the prepared statement */
const void **pzTail /* OUT: End of parsed string */
){
/* This function currently works by first transforming the UTF-16
** encoded string to UTF-8, then invoking sqlite3_prepare(). The
** tricky bit is figuring out the pointer to return in *pzTail.
*/
char *zSql8;
const char *zTail8 = 0;
int rc = SQLITE_OK;
if( sqlite3SafetyCheck(db) ){
return SQLITE_MISUSE;
}
sqlite3_mutex_enter(db->mutex);
zSql8 = sqlite3Utf16to8(db, zSql, nBytes);
if( zSql8 ){
rc = sqlite3LockAndPrepare(db, zSql8, -1, saveSqlFlag, ppStmt, &zTail8);
}
if( zTail8 && pzTail ){
/* If sqlite3_prepare returns a tail pointer, we calculate the
** equivalent pointer into the UTF-16 string by counting the unicode
** characters between zSql8 and zTail8, and then returning a pointer
** the same number of characters into the UTF-16 string.
*/
int chars_parsed = sqlite3Utf8CharLen(zSql8, zTail8-zSql8);
*pzTail = (u8 *)zSql + sqlite3Utf16ByteLen(zSql, chars_parsed);
}
sqlite3_free(zSql8);
rc = sqlite3ApiExit(db, rc);
sqlite3_mutex_leave(db->mutex);
return rc;
}
/*
** Two versions of the official API. Legacy and new use. In the legacy
** version, the original SQL text is not saved in the prepared statement
** and so if a schema change occurs, SQLITE_SCHEMA is returned by
** sqlite3_step(). In the new version, the original SQL text is retained
** and the statement is automatically recompiled if an schema change
** occurs.
*/
int sqlite3_prepare16(
sqlite3 *db, /* Database handle. */
const void *zSql, /* UTF-8 encoded SQL statement. */
int nBytes, /* Length of zSql in bytes. */
sqlite3_stmt **ppStmt, /* OUT: A pointer to the prepared statement */
const void **pzTail /* OUT: End of parsed string */
){
return sqlite3Prepare16(db,zSql,nBytes,0,ppStmt,pzTail);
}
int sqlite3_prepare16_v2(
sqlite3 *db, /* Database handle. */
const void *zSql, /* UTF-8 encoded SQL statement. */
int nBytes, /* Length of zSql in bytes. */
sqlite3_stmt **ppStmt, /* OUT: A pointer to the prepared statement */
const void **pzTail /* OUT: End of parsed string */
){
return sqlite3Prepare16(db,zSql,nBytes,1,ppStmt,pzTail);
}
#endif /* SQLITE_OMIT_UTF16 */