sqlite/src/main.c

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/*
** 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.c,v 1.216 2004/06/12 00:42:35 danielk1977 Exp $
*/
#include "sqliteInt.h"
#include "os.h"
#include <ctype.h>
/*
** A pointer to this structure is used to communicate information
** from sqlite3Init into the sqlite3InitCallback.
*/
typedef struct {
sqlite *db; /* The database being initialized */
char **pzErrMsg; /* Error message stored here */
} InitData;
/*
** The following constant value is used by the SQLITE_BIGENDIAN and
** SQLITE_LITTLEENDIAN macros.
*/
const int sqlite3one = 1;
/*
** Fill the InitData structure with an error message that indicates
** that the database is corrupt.
*/
static void corruptSchema(InitData *pData, const char *zExtra){
sqlite3SetString(pData->pzErrMsg, "malformed database schema",
zExtra!=0 && zExtra[0]!=0 ? " - " : (char*)0, zExtra, (char*)0);
}
/*
** This is the callback routine for the code that initializes the
** database. See sqlite3Init() below for additional information.
**
** Each callback contains the following information:
**
** argv[0] = "file-format" or "schema-cookie" or "table" or "index"
** argv[1] = table or index name or meta statement type.
** argv[2] = root page number for table or index. NULL for meta.
** argv[3] = SQL text for a CREATE TABLE or CREATE INDEX statement.
** argv[4] = "1" for temporary files, "0" for main database, "2" or more
** for auxiliary database files.
**
*/
static
int sqlite3InitCallback(void *pInit, int argc, char **argv, char **azColName){
InitData *pData = (InitData*)pInit;
int nErr = 0;
assert( argc==5 );
if( argv==0 ) return 0; /* Might happen if EMPTY_RESULT_CALLBACKS are on */
if( argv[0]==0 ){
corruptSchema(pData, 0);
return 1;
}
switch( argv[0][0] ){
case 'v':
case 'i':
case 't': { /* CREATE TABLE, CREATE INDEX, or CREATE VIEW statements */
sqlite *db = pData->db;
if( argv[2]==0 || argv[4]==0 ){
corruptSchema(pData, 0);
return 1;
}
if( argv[3] && argv[3][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;
assert( db->init.busy );
db->init.iDb = atoi(argv[4]);
assert( db->init.iDb>=0 && db->init.iDb<db->nDb );
db->init.newTnum = atoi(argv[2]);
if( sqlite3_exec(db, argv[3], 0, 0, &zErr) ){
corruptSchema(pData, zErr);
sqlite3_free(zErr);
}
db->init.iDb = 0;
}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.
*/
int iDb;
Index *pIndex;
iDb = atoi(argv[4]);
assert( iDb>=0 && iDb<db->nDb );
pIndex = sqlite3FindIndex(db, argv[1], 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[2]);
}
}
break;
}
default: {
/* This can not happen! */
nErr = 1;
assert( nErr==0 );
}
}
return nErr;
}
/*
** 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(sqlite *db, int iDb, char **pzErrMsg){
int rc;
BtCursor *curMain;
int size;
Table *pTab;
char *azArg[6];
char zDbNum[30];
int meta[10];
InitData initData;
/*
** The master database table has a structure like this
*/
static char master_schema[] =
"CREATE TABLE sqlite_master(\n"
" type text,\n"
" name text,\n"
" tbl_name text,\n"
" rootpage integer,\n"
" sql text\n"
")"
;
static 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"
")"
;
/* The following SQL will read the schema from the master tables.
*/
static char init_script1[] =
"SELECT type, name, rootpage, sql, 1 FROM sqlite_temp_master";
static char init_script2[] =
"SELECT type, name, rootpage, sql, 0 FROM sqlite_master";
assert( iDb>=0 && iDb!=1 && iDb<db->nDb );
/* Construct the schema tables: sqlite_master and sqlite_temp_master
*/
sqlite3SafetyOff(db);
azArg[0] = "table";
azArg[1] = MASTER_NAME;
azArg[2] = "1";
azArg[3] = master_schema;
sprintf(zDbNum, "%d", iDb);
azArg[4] = zDbNum;
azArg[5] = 0;
initData.db = db;
initData.pzErrMsg = pzErrMsg;
sqlite3InitCallback(&initData, 5, azArg, 0);
pTab = sqlite3FindTable(db, MASTER_NAME, "main");
if( pTab ){
pTab->readOnly = 1;
}
if( iDb==0 ){
azArg[1] = TEMP_MASTER_NAME;
azArg[3] = temp_master_schema;
azArg[4] = "1";
sqlite3InitCallback(&initData, 5, azArg, 0);
pTab = sqlite3FindTable(db, TEMP_MASTER_NAME, "temp");
if( pTab ){
pTab->readOnly = 1;
}
}
sqlite3SafetyOn(db);
/* Create a cursor to hold the database open
*/
if( db->aDb[iDb].pBt==0 ) return SQLITE_OK;
rc = sqlite3BtreeCursor(db->aDb[iDb].pBt, MASTER_ROOT, 0, 0, 0, &curMain);
if( rc!=SQLITE_OK && rc!=SQLITE_EMPTY ){
sqlite3SetString(pzErrMsg, sqlite3ErrStr(rc), (char*)0);
return rc;
}
/* 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] Synchronous setting. 1:off, 2:normal, 3:full
** meta[4] Db text encoding. 1:UTF-8 3:UTF-16 LE 4:UTF-16 BE
** meta[5] Pragma temp_store value. See comments on BtreeFactory
** meta[6]
** meta[7]
** meta[8]
** meta[9]
**
** Note: The hash 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(db->aDb[iDb].pBt, i+1, &meta[i]);
}
if( rc ){
sqlite3SetString(pzErrMsg, sqlite3ErrStr(rc), (char*)0);
sqlite3BtreeCloseCursor(curMain);
return rc;
}
}else{
memset(meta, 0, sizeof(meta));
}
db->aDb[iDb].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 db->enc. */
db->enc = (u8)meta[4];
db->pDfltColl = sqlite3FindCollSeq(db, db->enc, "BINARY", 6, 0);
}else{
/* If opening an attached database, the encoding much match db->enc */
if( meta[4]!=db->enc ){
sqlite3BtreeCloseCursor(curMain);
sqlite3SetString(pzErrMsg, "attached databases must use the same"
" text encoding as main database", (char*)0);
return SQLITE_ERROR;
}
}
}
if( iDb==0 ){
size = meta[2];
if( size==0 ){ size = MAX_PAGES; }
db->cache_size = size;
db->safety_level = meta[3];
if( meta[5]>0 && meta[5]<=2 && db->temp_store==0 ){
db->temp_store = meta[5];
}
if( db->safety_level==0 ) db->safety_level = 2;
/* FIX ME: Every struct Db will need a next_cookie */
db->next_cookie = meta[0];
db->file_format = meta[1];
if( db->file_format==0 ){
/* This happens if the database was initially empty */
db->file_format = 1;
}
}
/*
** file_format==1 Version 3.0.0.
*/
if( meta[1]>1 ){
sqlite3BtreeCloseCursor(curMain);
sqlite3SetString(pzErrMsg, "unsupported file format", (char*)0);
return SQLITE_ERROR;
}
sqlite3BtreeSetCacheSize(db->aDb[iDb].pBt, db->cache_size);
sqlite3BtreeSetSafetyLevel(db->aDb[iDb].pBt, meta[3]==0 ? 2 : meta[3]);
/* 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{
sqlite3SafetyOff(db);
if( iDb==0 ){
/* This SQL statement tries to read the temp.* schema from the
** sqlite_temp_master table. It might return SQLITE_EMPTY.
*/
rc = sqlite3_exec(db, init_script1, sqlite3InitCallback, &initData, 0);
if( rc==SQLITE_OK || rc==SQLITE_EMPTY ){
rc = sqlite3_exec(db, init_script2, sqlite3InitCallback, &initData, 0);
}
}else{
char *zSql = 0;
sqlite3SetString(&zSql,
"SELECT type, name, rootpage, sql, ", zDbNum, " FROM \"",
db->aDb[iDb].zName, "\".sqlite_master", (char*)0);
rc = sqlite3_exec(db, zSql, sqlite3InitCallback, &initData, 0);
sqliteFree(zSql);
}
sqlite3SafetyOn(db);
sqlite3BtreeCloseCursor(curMain);
}
if( sqlite3_malloc_failed ){
sqlite3SetString(pzErrMsg, "out of memory", (char*)0);
rc = SQLITE_NOMEM;
sqlite3ResetInternalSchema(db, 0);
}
if( rc==SQLITE_OK ){
DbSetProperty(db, iDb, DB_SchemaLoaded);
if( iDb==0 ){
DbSetProperty(db, 1, DB_SchemaLoaded);
}
}else{
sqlite3ResetInternalSchema(db, iDb);
}
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 the database is initialized, the SQLITE_Initialized
** bit is set in the flags field of the sqlite structure.
*/
int sqlite3Init(sqlite *db, char **pzErrMsg){
int i, rc;
if( db->init.busy ) return SQLITE_OK;
assert( (db->flags & SQLITE_Initialized)==0 );
rc = SQLITE_OK;
db->init.busy = 1;
for(i=0; rc==SQLITE_OK && i<db->nDb; i++){
if( DbHasProperty(db, i, DB_SchemaLoaded) ) continue;
assert( i!=1 ); /* Should have been initialized together with 0 */
rc = sqlite3InitOne(db, i, pzErrMsg);
if( rc ){
sqlite3ResetInternalSchema(db, i);
}
}
db->init.busy = 0;
if( rc==SQLITE_OK ){
db->flags |= SQLITE_Initialized;
sqlite3CommitInternalChanges(db);
}
if( rc!=SQLITE_OK ){
db->flags &= ~SQLITE_Initialized;
}
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(sqlite *db, char **pzErrMsg){
int rc = SQLITE_OK;
if( !db->init.busy ){
if( (db->flags & SQLITE_Initialized)==0 ){
rc = sqlite3Init(db, pzErrMsg);
}
}
assert( rc!=SQLITE_OK || (db->flags & SQLITE_Initialized)||db->init.busy );
return rc;
}
/*
** The version of the library
*/
const char rcsid[] = "@(#) \044Id: SQLite version " SQLITE_VERSION " $";
const char sqlite3_version[] = SQLITE_VERSION;
/*
** This is the default collating function named "BINARY" which is always
** available.
*/
static int binaryCollatingFunc(
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
*/
long long int sqlite3_last_insert_rowid(sqlite *db){
return db->lastRowid;
}
/*
** Return the number of changes in the most recent call to sqlite3_exec().
*/
int sqlite3_changes(sqlite *db){
return db->nChange;
}
/*
** Return the number of changes produced by the last INSERT, UPDATE, or
** DELETE statement to complete execution. The count does not include
** changes due to SQL statements executed in trigger programs that were
** triggered by that statement
*/
int sqlite3_last_statement_changes(sqlite *db){
return db->lsChange;
}
/*
** Close an existing SQLite database
*/
void sqlite3_close(sqlite *db){
HashElem *i;
int j;
db->want_to_close = 1;
if( sqlite3SafetyCheck(db) || sqlite3SafetyOn(db) ){
/* printf("DID NOT CLOSE\n"); fflush(stdout); */
return;
}
db->magic = SQLITE_MAGIC_CLOSED;
for(j=0; j<db->nDb; j++){
struct Db *pDb = &db->aDb[j];
if( pDb->pBt ){
sqlite3BtreeClose(pDb->pBt);
pDb->pBt = 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;
sqliteFree(pFunc);
}
}
for(i=sqliteHashFirst(&db->aFunc); i; i=sqliteHashNext(i)){
CollSeq *pColl = (CollSeq *)sqliteHashData(i);
/* sqliteFree(pColl); */
}
sqlite3HashClear(&db->aFunc);
sqlite3Error(db, SQLITE_OK, 0); /* Deallocates any cached error strings. */
sqliteFree(db);
}
/*
** Rollback all database files.
*/
void sqlite3RollbackAll(sqlite *db){
int i;
for(i=0; i<db->nDb; i++){
if( db->aDb[i].pBt ){
sqlite3BtreeRollback(db->aDb[i].pBt);
db->aDb[i].inTrans = 0;
}
}
sqlite3ResetInternalSchema(db, 0);
/* sqlite3RollbackInternalChanges(db); */
}
/*
** Return a static string that describes the kind of error specified in the
** argument.
*/
const char *sqlite3ErrStr(int rc){
const char *z;
switch( rc ){
case SQLITE_OK: z = "not an error"; break;
case SQLITE_ERROR: z = "SQL logic error or missing database"; break;
case SQLITE_INTERNAL: z = "internal SQLite implementation flaw"; 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_NOTFOUND: z = "table or record not found"; break;
case SQLITE_FULL: z = "database is full"; break;
case SQLITE_CANTOPEN: z = "unable to open database file"; break;
case SQLITE_PROTOCOL: z = "database locking protocol failure"; break;
case SQLITE_EMPTY: z = "table contains no data"; break;
case SQLITE_SCHEMA: z = "database schema has changed"; break;
case SQLITE_TOOBIG: z = "too much data for one table row"; 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 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 *Timeout, /* Maximum amount of time to wait */
const char *NotUsed, /* The name of the table that is busy */
int count /* Number of times table has been busy */
){
#if SQLITE_MIN_SLEEP_MS==1
static const char delays[] =
{ 1, 2, 5, 10, 15, 20, 25, 25, 25, 50, 50, 50, 100};
static const short int totals[] =
{ 0, 1, 3, 8, 18, 33, 53, 78, 103, 128, 178, 228, 287};
# define NDELAY (sizeof(delays)/sizeof(delays[0]))
int timeout = (int)Timeout;
int delay, prior;
if( count <= NDELAY ){
delay = delays[count-1];
prior = totals[count-1];
}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(delay);
return 1;
#else
int timeout = (int)Timeout;
if( (count+1)*1000 > timeout ){
return 0;
}
sqlite3OsSleep(1000);
return 1;
#endif
}
/*
** This routine sets the busy callback for an Sqlite database to the
** given callback function with the given argument.
*/
void sqlite3_busy_handler(
sqlite *db,
int (*xBusy)(void*,const char*,int),
void *pArg
){
db->busyHandler.xFunc = xBusy;
db->busyHandler.pArg = pArg;
}
#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.
*/
void sqlite3_progress_handler(
sqlite *db,
int nOps,
int (*xProgress)(void*),
void *pArg
){
if( nOps>0 ){
db->xProgress = xProgress;
db->nProgressOps = nOps;
db->pProgressArg = pArg;
}else{
db->xProgress = 0;
db->nProgressOps = 0;
db->pProgressArg = 0;
}
}
#endif
/*
** This routine installs a default busy handler that waits for the
** specified number of milliseconds before returning 0.
*/
void sqlite3_busy_timeout(sqlite *db, int ms){
if( ms>0 ){
sqlite3_busy_handler(db, sqliteDefaultBusyCallback, (void*)ms);
}else{
sqlite3_busy_handler(db, 0, 0);
}
}
/*
** Cause any pending operation to stop at its earliest opportunity.
*/
void sqlite3_interrupt(sqlite *db){
db->flags |= SQLITE_Interrupt;
}
/*
** Windows systems should call this routine to free memory that
** is returned in the in the errmsg parameter of sqlite3_open() when
** SQLite is a DLL. For some reason, it does not work to call free()
** directly.
**
** Note that we need to call free() not sqliteFree() here, since every
** string that is exported from SQLite should have already passed through
** sqlite3StrRealloc().
*/
void sqlite3_free(char *p){ free(p); }
/*
** Create new user functions.
*/
int sqlite3_create_function(
sqlite3 *db,
const char *zFunctionName,
int nArg,
int eTextRep,
int iCollateArg,
void *pUserData,
void (*xFunc)(sqlite3_context*,int,sqlite3_value **),
void (*xStep)(sqlite3_context*,int,sqlite3_value **),
void (*xFinal)(sqlite3_context*)
){
FuncDef *p;
int nName;
if( (db==0 || zFunctionName==0 || sqlite3SafetyCheck(db)) ||
(xFunc && (xFinal || xStep)) ||
(!xFunc && (xFinal && !xStep)) ||
(!xFunc && (!xFinal && xStep)) ||
(nArg<-1 || nArg>127) ||
(255<(nName = strlen(zFunctionName))) ){
return SQLITE_ERROR;
}
p = sqlite3FindFunction(db, zFunctionName, nName, nArg, eTextRep, 1);
if( p==0 ) return 1;
p->xFunc = xFunc;
p->xStep = xStep;
p->xFinalize = xFinal;
p->pUserData = pUserData;
return SQLITE_OK;
}
int sqlite3_create_function16(
sqlite3 *db,
const void *zFunctionName,
int nArg,
int eTextRep,
int iCollateArg,
void *pUserData,
void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
void (*xStep)(sqlite3_context*,int,sqlite3_value**),
void (*xFinal)(sqlite3_context*)
){
int rc;
char *zFunctionName8;
zFunctionName8 = sqlite3utf16to8(zFunctionName, -1, SQLITE_BIGENDIAN);
if( !zFunctionName8 ){
return SQLITE_NOMEM;
}
rc = sqlite3_create_function(db, zFunctionName8, nArg, eTextRep,
iCollateArg, pUserData, xFunc, xStep, xFinal);
sqliteFree(zFunctionName8);
return rc;
}
/*
** 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
** sqlite3_exec().
*/
void *sqlite3_trace(sqlite *db, void (*xTrace)(void*,const char*), void *pArg){
void *pOld = db->pTraceArg;
db->xTrace = xTrace;
db->pTraceArg = pArg;
return pOld;
}
/*** EXPERIMENTAL ***
**
** Register a function to be invoked when a transaction comments.
** If either function returns non-zero, then the commit becomes a
** rollback.
*/
void *sqlite3_commit_hook(
sqlite *db, /* Attach the hook to this database */
int (*xCallback)(void*), /* Function to invoke on each commit */
void *pArg /* Argument to the function */
){
void *pOld = db->pCommitArg;
db->xCommitCallback = xCallback;
db->pCommitArg = pArg;
return pOld;
}
/*
** 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 for temporary use only and is deleted as soon as the connection
** is closed.
**
** A temporary database can be either a disk file (that is automatically
** deleted when the file is closed) or a set of red-black trees held 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 sqlite *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 */
Btree **ppBtree /* Pointer to new Btree object written here */
){
int btree_flags = 0;
assert( ppBtree != 0);
if( omitJournal ){
btree_flags |= BTREE_OMIT_JOURNAL;
}
if( !zFilename ){
btree_flags |= BTREE_MEMORY;
}
return sqlite3BtreeOpen(zFilename, ppBtree, nCache, btree_flags,
&db->busyHandler);
}
/*
** Return UTF-8 encoded English language explanation of the most recent
** error.
*/
const char *sqlite3_errmsg(sqlite3 *db){
if( !db ){
/* If db is NULL, then assume that a malloc() failed during an
** sqlite3_open() call.
*/
return sqlite3ErrStr(SQLITE_NOMEM);
}
if( db->zErrMsg ){
return db->zErrMsg;
}
return sqlite3ErrStr(db->errCode);
}
/*
** Return UTF-16 encoded English language explanation of the most recent
** error.
*/
const void *sqlite3_errmsg16(sqlite3 *db){
if( !db ){
/* If db is NULL, then assume that a malloc() failed during an
** sqlite3_open() call. We have a static version of the string
** "out of memory" encoded using UTF-16 just for this purpose.
**
** 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 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 char *outOfMemLe = &outOfMemBe[1];
if( SQLITE_BIGENDIAN ){
return (void *)outOfMemBe;
}else{
return (void *)outOfMemLe;
}
}
if( !db->zErrMsg16 ){
char const *zErr8 = sqlite3_errmsg(db);
if( SQLITE_BIGENDIAN ){
db->zErrMsg16 = sqlite3utf8to16be(zErr8, -1);
}else{
db->zErrMsg16 = sqlite3utf8to16le(zErr8, -1);
}
}
return db->zErrMsg16;
}
int sqlite3_errcode(sqlite3 *db){
return db->errCode;
}
/*
** Check schema cookies in all databases except TEMP. If any cookie is out
** of date, return 0. If all schema cookies are current, return 1.
*/
static int schemaIsValid(sqlite *db){
int iDb;
int rc;
BtCursor *curTemp;
int cookie;
int allOk = 1;
for(iDb=0; allOk && iDb<db->nDb; iDb++){
Btree *pBt;
if( iDb==1 ) continue;
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, &cookie);
if( rc==SQLITE_OK && cookie!=db->aDb[iDb].schema_cookie ){
allOk = 0;
}
sqlite3BtreeCloseCursor(curTemp);
}
}
return allOk;
}
/*
** Compile the UTF-8 encoded SQL statement zSql into a statement handle.
*/
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 */
){
Parse sParse;
char *zErrMsg = 0;
int rc = SQLITE_OK;
if( sqlite3SafetyOn(db) ){
rc = SQLITE_MISUSE;
goto prepare_out;
}
if( db->pVdbe==0 ){ db->nChange = 0; }
memset(&sParse, 0, sizeof(sParse));
sParse.db = db;
sqlite3RunParser(&sParse, zSql, &zErrMsg);
if( db->xTrace && !db->init.busy ){
/* Trace only the statment that was compiled.
** Make a copy of that part of the SQL string since zSQL is const
** and we must pass a zero terminated string to the trace function
** The copy is unnecessary if the tail pointer is pointing at the
** beginnig or end of the SQL string.
*/
if( sParse.zTail && sParse.zTail!=zSql && *sParse.zTail ){
char *tmpSql = sqliteStrNDup(zSql, sParse.zTail - zSql);
if( tmpSql ){
db->xTrace(db->pTraceArg, tmpSql);
free(tmpSql);
}else{
/* If a memory error occurred during the copy,
** trace entire SQL string and fall through to the
** sqlite3_malloc_failed test to report the error.
*/
db->xTrace(db->pTraceArg, zSql);
}
}else{
db->xTrace(db->pTraceArg, zSql);
}
}
/* 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 && sParse.zTail && sParse.zTail!=zSql ){
sqlite3DebugPrintf("SQL-trace: %.*s\n", sParse.zTail - zSql, zSql);
}
#endif /* SQLITE_DEBUG */
if( sqlite3_malloc_failed ){
rc = SQLITE_NOMEM;
sqlite3RollbackAll(db);
sqlite3ResetInternalSchema(db, 0);
db->flags &= ~SQLITE_InTrans;
goto prepare_out;
}
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);
}
assert( ppStmt );
*ppStmt = (sqlite3_stmt*)sParse.pVdbe;
if( pzTail ) *pzTail = sParse.zTail;
rc = sParse.rc;
if( rc==SQLITE_OK && sParse.pVdbe && sParse.explain ){
sqlite3VdbeSetNumCols(sParse.pVdbe, 5);
sqlite3VdbeSetColName(sParse.pVdbe, 0, "addr", P3_STATIC);
sqlite3VdbeSetColName(sParse.pVdbe, 1, "opcode", P3_STATIC);
sqlite3VdbeSetColName(sParse.pVdbe, 2, "p1", P3_STATIC);
sqlite3VdbeSetColName(sParse.pVdbe, 3, "p2", P3_STATIC);
sqlite3VdbeSetColName(sParse.pVdbe, 4, "p3", P3_STATIC);
}
prepare_out:
if( sqlite3SafetyOff(db) ){
rc = SQLITE_MISUSE;
}
if( zErrMsg ){
sqlite3Error(db, rc, "%s", zErrMsg);
}else{
sqlite3Error(db, rc, 0);
}
return rc;
}
/*
** Compile the UTF-16 encoded SQL statement zSql into a statement handle.
*/
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 */
){
/* 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 = 0;
char const *zTail8 = 0;
int rc;
zSql8 = sqlite3utf16to8(zSql, nBytes, SQLITE_BIGENDIAN);
if( !zSql8 ){
sqlite3Error(db, SQLITE_NOMEM, 0);
return SQLITE_NOMEM;
}
rc = sqlite3_prepare(db, zSql8, -1, 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);
}
return rc;
}
/*
** 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. The fourth argument, "def_enc" is one of the TEXT_*
** macros from sqliteInt.h. If we end up creating a new database file
** (not opening an existing one), the text encoding of the database
** will be set to this value.
*/
static int openDatabase(
const char *zFilename, /* Database filename UTF-8 encoded */
sqlite3 **ppDb /* OUT: Returned database handle */
){
sqlite3 *db;
int rc, i;
char *zErrMsg = 0;
/* Allocate the sqlite data structure */
db = sqliteMalloc( sizeof(sqlite) );
if( db==0 ) goto opendb_out;
db->priorNewRowid = 0;
db->magic = SQLITE_MAGIC_BUSY;
db->nDb = 2;
db->aDb = db->aDbStatic;
db->enc = SQLITE_UTF8;
db->autoCommit = 1;
/* db->flags |= SQLITE_ShortColNames; */
sqlite3HashInit(&db->aFunc, SQLITE_HASH_STRING, 0);
sqlite3HashInit(&db->aCollSeq, SQLITE_HASH_STRING, 0);
for(i=0; i<db->nDb; i++){
sqlite3HashInit(&db->aDb[i].tblHash, SQLITE_HASH_STRING, 0);
sqlite3HashInit(&db->aDb[i].idxHash, SQLITE_HASH_STRING, 0);
sqlite3HashInit(&db->aDb[i].trigHash, SQLITE_HASH_STRING, 0);
sqlite3HashInit(&db->aDb[i].aFKey, SQLITE_HASH_STRING, 1);
}
/* 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.
*/
sqlite3_create_collation(db, "BINARY", SQLITE_UTF8, 0,binaryCollatingFunc);
sqlite3_create_collation(db, "BINARY", SQLITE_UTF16LE, 0,binaryCollatingFunc);
sqlite3_create_collation(db, "BINARY", SQLITE_UTF16BE, 0,binaryCollatingFunc);
db->pDfltColl = sqlite3FindCollSeq(db, db->enc, "BINARY", 6, 0);
if( !db->pDfltColl ){
rc = db->errCode;
assert( rc!=SQLITE_OK );
db->magic = SQLITE_MAGIC_CLOSED;
goto opendb_out;
}
/* Also add a UTF-8 case-insensitive collation sequence. */
sqlite3_create_collation(db, "NOCASE", SQLITE_UTF8, 0, nocaseCollatingFunc);
/* Open the backend database driver */
if( zFilename[0]==':' && strcmp(zFilename,":memory:")==0 ){
db->temp_store = 2;
db->nMaster = 0; /* Disable atomic multi-file commit for :memory: */
}else{
db->nMaster = -1; /* Size of master journal filename initially unknown */
}
rc = sqlite3BtreeFactory(db, zFilename, 0, MAX_PAGES, &db->aDb[0].pBt);
if( rc!=SQLITE_OK ){
/* FIX ME: sqlite3BtreeFactory() should call sqlite3Error(). */
sqlite3Error(db, rc, 0);
db->magic = SQLITE_MAGIC_CLOSED;
goto opendb_out;
}
db->aDb[0].zName = "main";
db->aDb[1].zName = "temp";
/* 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.
*/
sqlite3RegisterBuiltinFunctions(db);
if( rc==SQLITE_OK ){
db->magic = SQLITE_MAGIC_OPEN;
}else{
sqlite3Error(db, rc, "%s", zErrMsg, 0);
if( zErrMsg ) sqliteFree(zErrMsg);
db->magic = SQLITE_MAGIC_CLOSED;
}
opendb_out:
*ppDb = db;
return sqlite3_errcode(db);
}
/*
** Open a new database handle.
*/
int sqlite3_open(
const char *zFilename,
sqlite3 **ppDb
){
return openDatabase(zFilename, ppDb);
}
/*
** Open a new database handle.
*/
int sqlite3_open16(
const void *zFilename,
sqlite3 **ppDb
){
char *zFilename8; /* zFilename encoded in UTF-8 instead of UTF-16 */
int rc;
assert( ppDb );
zFilename8 = sqlite3utf16to8(zFilename, -1, SQLITE_BIGENDIAN);
if( !zFilename8 ){
*ppDb = 0;
return SQLITE_NOMEM;
}
rc = openDatabase(zFilename8, ppDb);
if( rc==SQLITE_OK && *ppDb ){
sqlite3_exec(*ppDb, "PRAGMA encoding = 'UTF-16'", 0, 0, 0);
}
sqliteFree(zFilename8);
return rc;
}
/*
** 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().
*/
int sqlite3_finalize(sqlite3_stmt *pStmt){
return sqlite3VdbeFinalize((Vdbe*)pStmt, 0);
}
/*
** 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().
*/
int sqlite3_reset(sqlite3_stmt *pStmt){
int rc = sqlite3VdbeReset((Vdbe*)pStmt, 0);
sqlite3VdbeMakeReady((Vdbe*)pStmt, -1, 0);
return rc;
}
int sqlite3_create_collation(
sqlite3* db,
const char *zName,
int enc,
void* pCtx,
int(*xCompare)(void*,int,const void*,int,const void*)
){
CollSeq *pColl;
int rc = SQLITE_OK;
if( enc!=SQLITE_UTF8 && enc!=SQLITE_UTF16LE && enc!=SQLITE_UTF16BE ){
sqlite3Error(db, SQLITE_ERROR,
"Param 3 to sqlite3_create_collation() must be one of "
"SQLITE_UTF8, SQLITE_UTF16LE or SQLITE_UTF16BE"
);
return SQLITE_ERROR;
}
pColl = sqlite3FindCollSeq(db, (u8)enc, zName, strlen(zName), 1);
if( 0==pColl ){
rc = SQLITE_NOMEM;
}else{
pColl->xCmp = xCompare;
pColl->pUser = pCtx;
}
sqlite3Error(db, rc, 0);
return rc;
}
int sqlite3_create_collation16(
sqlite3* db,
const char *zName,
int enc,
void* pCtx,
int(*xCompare)(void*,int,const void*,int,const void*)
){
int rc;
char *zName8 = sqlite3utf16to8(zName, -1, SQLITE_BIGENDIAN);
rc = sqlite3_create_collation(db, zName8, enc, pCtx, xCompare);
sqliteFree(zName8);
return rc;
}
int sqlite3_collation_needed(
sqlite3 *db,
void *pCollNeededArg,
void(*xCollNeeded)(void*,sqlite3*,int eTextRep,const char*)
){
db->xCollNeeded = xCollNeeded;
db->xCollNeeded16 = 0;
db->pCollNeededArg = pCollNeededArg;
return SQLITE_OK;
}
int sqlite3_collation_needed16(
sqlite3 *db,
void *pCollNeededArg,
void(*xCollNeeded16)(void*,sqlite3*,int eTextRep,const void*)
){
db->xCollNeeded = 0;
db->xCollNeeded16 = xCollNeeded16;
db->pCollNeededArg = pCollNeededArg;
return SQLITE_OK;
}