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sourcemod/extensions/sqlite/sqlite-source/prepare.c
David Anderson f78ceafdce updated to sqlite-3.5.1 now that it's stable 
used new shared cache functionality (yay)

--HG--
extra : convert_revision : svn%3A39bc706e-5318-0410-9160-8a85361fbb7c/trunk%401651
2007-10-28 05:48:06 +00:00

743 lines
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C
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/*
** 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 */
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