/*
** Initialize the temporary index cursor just opened as a sorter cursor.
*/
int sqlite3VdbeSorterInit(sqlite3 *db, VdbeCursor *pCsr){
int pgsz; /* Page size of main database */
int mxCache; /* Cache size */
VdbeSorter *pSorter; /* The new sorter */
char *d; /* Dummy */
assert( pCsr->pKeyInfo && pCsr->pBt==0 );
pCsr->pSorter = pSorter = sqlite3DbMallocZero(db, sizeof(VdbeSorter));
if( pSorter==0 ){
return SQLITE_NOMEM;
}
pSorter->pUnpacked = sqlite3VdbeAllocUnpackedRecord(pCsr->pKeyInfo, 0, 0, &d);
if( pSorter->pUnpacked==0 ) return SQLITE_NOMEM;
assert( pSorter->pUnpacked==(UnpackedRecord *)d );
if( !sqlite3TempInMemory(db) ){
pgsz = sqlite3BtreeGetPageSize(db->aDb[0].pBt);
pSorter->mnPmaSize = SORTER_MIN_WORKING * pgsz;
mxCache = db->aDb[0].pSchema->cache_size;
if( mxCache<SORTER_MIN_WORKING ) mxCache = SORTER_MIN_WORKING;
pSorter->mxPmaSize = mxCache * pgsz;
}
return SQLITE_OK;
}
/*
** Build a trigger step out of an INSERT statement. Return a pointer
** to the new trigger step.
**
** The parser calls this routine when it sees an INSERT inside the
** body of a trigger.
*/
TriggerStep *sqlite3TriggerInsertStep(
sqlite3 *db, /* The database connection */
Token *pTableName, /* Name of the table into which we insert */
IdList *pColumn, /* List of columns in pTableName to insert into */
ExprList *pEList, /* The VALUE clause: a list of values to be inserted */
Select *pSelect, /* A SELECT statement that supplies values */
int orconf /* The conflict algorithm (OE_Abort, OE_Replace, etc.) */
){
TriggerStep *pTriggerStep;
assert(pEList == 0 || pSelect == 0);
assert(pEList != 0 || pSelect != 0 || db->mallocFailed);
pTriggerStep = (TriggerStep*)sqlite3DbMallocZero(db, sizeof(TriggerStep));
if( pTriggerStep ){
pTriggerStep->op = TK_INSERT;
pTriggerStep->pSelect = pSelect;
pTriggerStep->target = *pTableName;
pTriggerStep->pIdList = pColumn;
pTriggerStep->pExprList = pEList;
pTriggerStep->orconf = orconf;
sqlitePersistTriggerStep(db, pTriggerStep);
}else{
sqlite3IdListDelete(pColumn);
sqlite3ExprListDelete(pEList);
sqlite3SelectDelete(pSelect);
}
return pTriggerStep;
}
/*
** Check to see if virtual table module pMod can be have an eponymous
** virtual table instance. If it can, create one if one does not already
** exist. Return non-zero if the eponymous virtual table instance exists
** when this routine returns, and return zero if it does not exist.
**
** An eponymous virtual table instance is one that is named after its
** module, and more importantly, does not require a CREATE VIRTUAL TABLE
** statement in order to come into existance. Eponymous virtual table
** instances always exist. They cannot be DROP-ed.
**
** Any virtual table module for which xConnect and xCreate are the same
** method can have an eponymous virtual table instance.
*/
int sqlite3VtabEponymousTableInit(Parse *pParse, Module *pMod){
const sqlite3_module *pModule = pMod->pModule;
Table *pTab;
char *zErr = 0;
int rc;
sqlite3 *db = pParse->db;
if( pMod->pEpoTab ) return 1;
if( pModule->xCreate!=0 && pModule->xCreate!=pModule->xConnect ) return 0;
pTab = sqlite3DbMallocZero(db, sizeof(Table));
if( pTab==0 ) return 0;
pTab->zName = sqlite3DbStrDup(db, pMod->zName);
if( pTab->zName==0 ){
sqlite3DbFree(db, pTab);
return 0;
}
pMod->pEpoTab = pTab;
pTab->nTabRef = 1;
pTab->pSchema = db->aDb[0].pSchema;
pTab->tabFlags |= TF_Virtual;
pTab->nModuleArg = 0;
pTab->iPKey = -1;
addModuleArgument(db, pTab, sqlite3DbStrDup(db, pTab->zName));
addModuleArgument(db, pTab, 0);
addModuleArgument(db, pTab, sqlite3DbStrDup(db, pTab->zName));
rc = vtabCallConstructor(db, pTab, pMod, pModule->xConnect, &zErr);
if( rc ){
sqlite3ErrorMsg(pParse, "%s", zErr);
sqlite3DbFree(db, zErr);
sqlite3VtabEponymousTableClear(db, pMod);
return 0;
}
return 1;
}
/*
** The first parameter (pDef) is a function implementation. The
** second parameter (pExpr) is the first argument to this function.
** If pExpr is a column in a virtual table, then let the virtual
** table implementation have an opportunity to overload the function.
**
** This routine is used to allow virtual table implementations to
** overload MATCH, LIKE, GLOB, and REGEXP operators.
**
** Return either the pDef argument (indicating no change) or a
** new FuncDef structure that is marked as ephemeral using the
** SQLITE_FUNC_EPHEM flag.
*/
FuncDef *sqlite3VtabOverloadFunction(
sqlite3 *db, /* Database connection for reporting malloc problems */
FuncDef *pDef, /* Function to possibly overload */
int nArg, /* Number of arguments to the function */
Expr *pExpr /* First argument to the function */
){
Table *pTab;
sqlite3_vtab *pVtab;
sqlite3_module *pMod;
void (*xSFunc)(sqlite3_context*,int,sqlite3_value**) = 0;
void *pArg = 0;
FuncDef *pNew;
int rc = 0;
char *zLowerName;
unsigned char *z;
/* Check to see the left operand is a column in a virtual table */
if( NEVER(pExpr==0) ) return pDef;
if( pExpr->op!=TK_COLUMN ) return pDef;
pTab = pExpr->pTab;
if( NEVER(pTab==0) ) return pDef;
if( (pTab->tabFlags & TF_Virtual)==0 ) return pDef;
pVtab = sqlite3GetVTable(db, pTab)->pVtab;
assert( pVtab!=0 );
assert( pVtab->pModule!=0 );
pMod = (sqlite3_module *)pVtab->pModule;
if( pMod->xFindFunction==0 ) return pDef;
/* Call the xFindFunction method on the virtual table implementation
** to see if the implementation wants to overload this function
*/
zLowerName = sqlite3DbStrDup(db, pDef->zName);
if( zLowerName ){
for(z=(unsigned char*)zLowerName; *z; z++){
*z = sqlite3UpperToLower[*z];
}
rc = pMod->xFindFunction(pVtab, nArg, zLowerName, &xSFunc, &pArg);
sqlite3DbFree(db, zLowerName);
}
if( rc==0 ){
return pDef;
}
/* Create a new ephemeral function definition for the overloaded
** function */
pNew = sqlite3DbMallocZero(db, sizeof(*pNew)
+ sqlite3Strlen30(pDef->zName) + 1);
if( pNew==0 ){
return pDef;
}
*pNew = *pDef;
pNew->zName = (const char*)&pNew[1];
memcpy((char*)&pNew[1], pDef->zName, sqlite3Strlen30(pDef->zName)+1);
pNew->xSFunc = xSFunc;
pNew->pUserData = pArg;
pNew->funcFlags |= SQLITE_FUNC_EPHEM;
return pNew;
}
/*
** Create a new sqlite3_value object.
*/
sqlite3_value *sqlite3ValueNew(sqlite3 *db){
Mem *p = sqlite3DbMallocZero(db, sizeof(*p));
if( p ){
p->flags = MEM_Null;
p->type = SQLITE_NULL;
p->db = db;
}
return p;
}
/*
** Turn a SELECT statement (that the pSelect parameter points to) into
** a trigger step. Return a pointer to a TriggerStep structure.
**
** The parser calls this routine when it finds a SELECT statement in
** body of a TRIGGER.
*/
SQLITE_PRIVATE TriggerStep *sqlite3TriggerSelectStep(sqlite3 *db, Select *pSelect){
TriggerStep *pTriggerStep = sqlite3DbMallocZero(db, sizeof(TriggerStep));
if( pTriggerStep==0 ) {
sqlite3SelectDelete(db, pSelect);
return 0;
}
pTriggerStep->op = TK_SELECT;
pTriggerStep->pSelect = pSelect;
pTriggerStep->orconf = OE_Default;
return pTriggerStep;
}
/*
** Turn a SELECT statement (that the pSelect parameter points to) into
** a trigger step. Return a pointer to a TriggerStep structure.
**
** The parser calls this routine when it finds a SELECT statement in
** body of a TRIGGER.
*/
TriggerStep *sqlite3TriggerSelectStep(sqlite3 *db, Select *pSelect){
TriggerStep *pTriggerStep = (TriggerStep*)sqlite3DbMallocZero(db, sizeof(TriggerStep));
if( pTriggerStep==0 ) {
sqlite3SelectDelete(pSelect);
return 0;
}
pTriggerStep->op = TK_SELECT;
pTriggerStep->pSelect = pSelect;
pTriggerStep->orconf = OE_Default;
sqlitePersistTriggerStep(db, pTriggerStep);
return pTriggerStep;
}
/*
** Turn a SELECT statement (that the pSelect parameter points to) into
** a trigger step. Return a pointer to a TriggerStep structure.
**
** The parser calls this routine when it finds a SELECT statement in
** body of a TRIGGER.
*/
TriggerStep *sqlite3TriggerSelectStep(
sqlite3 *db, /* Database connection */
Select *pSelect, /* The SELECT statement */
const char *zStart, /* Start of SQL text */
const char *zEnd /* End of SQL text */
){
TriggerStep *pTriggerStep = sqlite3DbMallocZero(db, sizeof(TriggerStep));
if( pTriggerStep==0 ) {
sqlite3SelectDelete(db, pSelect);
return 0;
}
pTriggerStep->op = TK_SELECT;
pTriggerStep->pSelect = pSelect;
pTriggerStep->orconf = OE_Default;
pTriggerStep->zSpan = triggerSpanDup(db, zStart, zEnd);
return pTriggerStep;
}
/*
** Allocate space to hold a new trigger step. The allocated space
** holds both the TriggerStep object and the TriggerStep.target.z string.
**
** If an OOM error occurs, NULL is returned and db->mallocFailed is set.
*/
static TriggerStep *triggerStepAllocate(
sqlite3 *db, /* Database connection */
u8 op, /* Trigger opcode */
Token *pName /* The target name */
){
TriggerStep *pTriggerStep;
pTriggerStep = sqlite3DbMallocZero(db, sizeof(TriggerStep) + pName->n);
if( pTriggerStep ){
char *z = (char*)&pTriggerStep[1];
memcpy(z, pName->z, pName->n);
pTriggerStep->target.z = z;
pTriggerStep->target.n = pName->n;
pTriggerStep->op = op;
}
return pTriggerStep;
}
/*
** Find and return the schema associated with a BTree. Create
** a new one if necessary.
*/
Schema *sqlite3SchemaGet(sqlite3 *db, Btree *pBt){
Schema * p;
if( pBt ){
p = (Schema *)sqlite3BtreeSchema(pBt, sizeof(Schema), sqlite3SchemaClear);
}else{
p = (Schema *)sqlite3DbMallocZero(0, sizeof(Schema));
}
if( !p ){
sqlite3OomFault(db);
}else if ( 0==p->file_format ){
sqlite3HashInit(&p->tblHash);
sqlite3HashInit(&p->idxHash);
sqlite3HashInit(&p->trigHash);
sqlite3HashInit(&p->fkeyHash);
p->enc = SQLITE_UTF8;
}
return p;
}
/*
** Set the auxiliary data pointer and delete function, for the iArg'th
** argument to the user-function defined by pCtx. Any previous value is
** deleted by calling the delete function specified when it was set.
*/
void sqlite3_set_auxdata(
sqlite3_context *pCtx,
int iArg,
void *pAux,
void (*xDelete)(void*)
){
AuxData *pAuxData;
Vdbe *pVdbe = pCtx->pVdbe;
assert( sqlite3_mutex_held(pCtx->pOut->db->mutex) );
if( iArg<0 ) goto failed;
#ifdef SQLITE_ENABLE_STAT3_OR_STAT4
if( pVdbe==0 ) goto failed;
#else
assert( pVdbe!=0 );
#endif
for(pAuxData=pVdbe->pAuxData; pAuxData; pAuxData=pAuxData->pNext){
if( pAuxData->iOp==pCtx->iOp && pAuxData->iArg==iArg ) break;
}
if( pAuxData==0 ){
pAuxData = sqlite3DbMallocZero(pVdbe->db, sizeof(AuxData));
if( !pAuxData ) goto failed;
pAuxData->iOp = pCtx->iOp;
pAuxData->iArg = iArg;
pAuxData->pNext = pVdbe->pAuxData;
pVdbe->pAuxData = pAuxData;
if( pCtx->fErrorOrAux==0 ){
pCtx->isError = 0;
pCtx->fErrorOrAux = 1;
}
}else if( pAuxData->xDelete ){
pAuxData->xDelete(pAuxData->pAux);
}
pAuxData->pAux = pAux;
pAuxData->xDelete = xDelete;
return;
failed:
if( xDelete ){
xDelete(pAux);
}
}
/*
** Construct a trigger step that implements a DELETE statement and return
** a pointer to that trigger step. The parser calls this routine when it
** sees a DELETE statement inside the body of a CREATE TRIGGER.
*/
TriggerStep *sqlite3TriggerDeleteStep(
sqlite3 *db, /* Database connection */
Token *pTableName, /* The table from which rows are deleted */
Expr *pWhere /* The WHERE clause */
){
TriggerStep *pTriggerStep = (TriggerStep*)sqlite3DbMallocZero(db, sizeof(TriggerStep));
if( pTriggerStep==0 ){
sqlite3ExprDelete(pWhere);
return 0;
}
pTriggerStep->op = TK_DELETE;
pTriggerStep->target = *pTableName;
pTriggerStep->pWhere = pWhere;
pTriggerStep->orconf = OE_Default;
sqlitePersistTriggerStep(db, pTriggerStep);
return pTriggerStep;
}
/*
** Allocate and return a pointer to a new sqlite3_value object. If
** the second argument to this function is NULL, the object is allocated
** by calling sqlite3ValueNew().
**
** Otherwise, if the second argument is non-zero, then this function is
** being called indirectly by sqlite3Stat4ProbeSetValue(). If it has not
** already been allocated, allocate the UnpackedRecord structure that
** that function will return to its caller here. Then return a pointer
** an sqlite3_value within the UnpackedRecord.a[] array.
*/
static sqlite3_value *valueNew(sqlite3 *db, struct ValueNewStat4Ctx *p){
#ifdef SQLITE_ENABLE_STAT3_OR_STAT4
if( p ){
UnpackedRecord *pRec = p->ppRec[0];
if( pRec==0 ){
Index *pIdx = p->pIdx; /* Index being probed */
int nByte; /* Bytes of space to allocate */
int i; /* Counter variable */
int nCol = pIdx->nColumn+1; /* Number of index columns including rowid */
nByte = sizeof(Mem) * nCol + sizeof(UnpackedRecord);
pRec = (UnpackedRecord*)sqlite3DbMallocZero(db, nByte);
if( pRec ){
pRec->pKeyInfo = sqlite3IndexKeyinfo(p->pParse, pIdx);
if( pRec->pKeyInfo ){
assert( pRec->pKeyInfo->nField+1==nCol );
pRec->pKeyInfo->enc = ENC(db);
pRec->flags = UNPACKED_PREFIX_MATCH;
pRec->aMem = (Mem *)&pRec[1];
for(i=0; i<nCol; i++){
pRec->aMem[i].flags = MEM_Null;
pRec->aMem[i].type = SQLITE_NULL;
pRec->aMem[i].db = db;
}
}else{
sqlite3DbFree(db, pRec);
pRec = 0;
}
}
if( pRec==0 ) return 0;
p->ppRec[0] = pRec;
}
pRec->nField = p->iVal+1;
return &pRec->aMem[p->iVal];
}
#else
UNUSED_PARAMETER(p);
#endif /* defined(SQLITE_ENABLE_STAT3_OR_STAT4) */
return sqlite3ValueNew(db);
}
/*
** Locate and return an entry from the db.aCollSeq hash table. If the entry
** specified by zName and nName is not found and parameter 'create' is
** true, then create a new entry. Otherwise return NULL.
**
** Each pointer stored in the sqlite3.aCollSeq hash table contains an
** array of three CollSeq structures. The first is the collation sequence
** prefferred for UTF-8, the second UTF-16le, and the third UTF-16be.
**
** Stored immediately after the three collation sequences is a copy of
** the collation sequence name. A pointer to this string is stored in
** each collation sequence structure.
*/
static CollSeq *findCollSeqEntry(
sqlite3 *db,
const char *zName,
int nName,
int create
){
CollSeq *pColl;
if( nName<0 ) nName = sqlite3Strlen(db, zName);
pColl = sqlite3HashFind(&db->aCollSeq, zName, nName);
if( 0==pColl && create ){
pColl = sqlite3DbMallocZero(db, 3*sizeof(*pColl) + nName + 1 );
if( pColl ){
CollSeq *pDel = 0;
pColl[0].zName = (char*)&pColl[3];
pColl[0].enc = SQLITE_UTF8;
pColl[1].zName = (char*)&pColl[3];
pColl[1].enc = SQLITE_UTF16LE;
pColl[2].zName = (char*)&pColl[3];
pColl[2].enc = SQLITE_UTF16BE;
memcpy(pColl[0].zName, zName, nName);
pColl[0].zName[nName] = 0;
pDel = sqlite3HashInsert(&db->aCollSeq, pColl[0].zName, nName, pColl);
/* If a malloc() failure occured in sqlite3HashInsert(), it will
** return the pColl pointer to be deleted (because it wasn't added
** to the hash table).
*/
assert( pDel==0 || pDel==pColl );
if( pDel!=0 ){
db->mallocFailed = 1;
sqlite3DbFree(db, pDel);
pColl = 0;
}
}
}
return pColl;
}
/*
** Construct a trigger step that implements an UPDATE statement and return
** a pointer to that trigger step. The parser calls this routine when it
** sees an UPDATE statement inside the body of a CREATE TRIGGER.
*/
TriggerStep *sqlite3TriggerUpdateStep(
sqlite3 *db, /* The database connection */
Token *pTableName, /* Name of the table to be updated */
ExprList *pEList, /* The SET clause: list of column and new values */
Expr *pWhere, /* The WHERE clause */
int orconf /* The conflict algorithm. (OE_Abort, OE_Ignore, etc) */
){
TriggerStep *pTriggerStep = (TriggerStep*)sqlite3DbMallocZero(db, sizeof(TriggerStep));
if( pTriggerStep==0 ){
sqlite3ExprListDelete(pEList);
sqlite3ExprDelete(pWhere);
return 0;
}
pTriggerStep->op = TK_UPDATE;
pTriggerStep->target = *pTableName;
pTriggerStep->pExprList = pEList;
pTriggerStep->pWhere = pWhere;
pTriggerStep->orconf = orconf;
sqlitePersistTriggerStep(db, pTriggerStep);
return pTriggerStep;
}
/*
** Locate and return an entry from the db.aCollSeq hash table. If the entry
** specified by zName and nName is not found and parameter 'create' is
** true, then create a new entry. Otherwise return NULL.
**
** Each pointer stored in the sqlite3.aCollSeq hash table contains an
** array of three CollSeq structures. The first is the collation sequence
** preferred for UTF-8, the second UTF-16le, and the third UTF-16be.
**
** Stored immediately after the three collation sequences is a copy of
** the collation sequence name. A pointer to this string is stored in
** each collation sequence structure.
*/
static CollSeq *findCollSeqEntry(
sqlite3 *db, /* Database connection */
const char *zName, /* Name of the collating sequence */
int create /* Create a new entry if true */
){
CollSeq *pColl;
pColl = sqlite3HashFind(&db->aCollSeq, zName);
if( 0==pColl && create ){
int nName = sqlite3Strlen30(zName) + 1;
pColl = sqlite3DbMallocZero(db, 3*sizeof(*pColl) + nName);
if( pColl ){
CollSeq *pDel = 0;
pColl[0].zName = (char*)&pColl[3];
pColl[0].enc = SQLITE_UTF8;
pColl[1].zName = (char*)&pColl[3];
pColl[1].enc = SQLITE_UTF16LE;
pColl[2].zName = (char*)&pColl[3];
pColl[2].enc = SQLITE_UTF16BE;
memcpy(pColl[0].zName, zName, nName);
pDel = sqlite3HashInsert(&db->aCollSeq, pColl[0].zName, pColl);
/* If a malloc() failure occurred in sqlite3HashInsert(), it will
** return the pColl pointer to be deleted (because it wasn't added
** to the hash table).
*/
assert( pDel==0 || pDel==pColl );
if( pDel!=0 ){
sqlite3OomFault(db);
sqlite3DbFree(db, pDel);
pColl = 0;
}
}
}
return pColl;
}
/*
** Allocate space to hold a new trigger step. The allocated space
** holds both the TriggerStep object and the TriggerStep.target.z string.
**
** If an OOM error occurs, NULL is returned and db->mallocFailed is set.
*/
static TriggerStep *triggerStepAllocate(
Parse *pParse, /* Parser context */
u8 op, /* Trigger opcode */
Token *pName, /* The target name */
const char *zStart, /* Start of SQL text */
const char *zEnd /* End of SQL text */
){
sqlite3 *db = pParse->db;
TriggerStep *pTriggerStep;
pTriggerStep = sqlite3DbMallocZero(db, sizeof(TriggerStep) + pName->n + 1);
if( pTriggerStep ){
char *z = (char*)&pTriggerStep[1];
memcpy(z, pName->z, pName->n);
sqlite3Dequote(z);
pTriggerStep->zTarget = z;
pTriggerStep->op = op;
pTriggerStep->zSpan = triggerSpanDup(db, zStart, zEnd);
if( IN_RENAME_OBJECT ){
sqlite3RenameTokenMap(pParse, pTriggerStep->zTarget, pName);
}
}
return pTriggerStep;
}
/*
** Locate a user function given a name, a number of arguments and a flag
** indicating whether the function prefers UTF-16 over UTF-8. Return a
** pointer to the FuncDef structure that defines that function, or return
** NULL if the function does not exist.
**
** If the createFlag argument is true, then a new (blank) FuncDef
** structure is created and liked into the "db" structure if a
** no matching function previously existed.
**
** If nArg is -2, then the first valid function found is returned. A
** function is valid if xSFunc is non-zero. The nArg==(-2)
** case is used to see if zName is a valid function name for some number
** of arguments. If nArg is -2, then createFlag must be 0.
**
** If createFlag is false, then a function with the required name and
** number of arguments may be returned even if the eTextRep flag does not
** match that requested.
*/
FuncDef *sqlite3FindFunction(
sqlite3 *db, /* An open database */
const char *zName, /* Name of the function. zero-terminated */
int nArg, /* Number of arguments. -1 means any number */
u8 enc, /* Preferred text encoding */
u8 createFlag /* Create new entry if true and does not otherwise exist */
){
FuncDef *p; /* Iterator variable */
FuncDef *pBest = 0; /* Best match found so far */
int bestScore = 0; /* Score of best match */
int h; /* Hash value */
int nName; /* Length of the name */
assert( nArg>=(-2) );
assert( nArg>=(-1) || createFlag==0 );
nName = sqlite3Strlen30(zName);
/* First search for a match amongst the application-defined functions.
*/
p = (FuncDef*)sqlite3HashFind(&db->aFunc, zName);
while( p ){
int score = matchQuality(p, nArg, enc);
if( score>bestScore ){
pBest = p;
bestScore = score;
}
p = p->pNext;
}
/* If no match is found, search the built-in functions.
**
** If the DBFLAG_PreferBuiltin flag is set, then search the built-in
** functions even if a prior app-defined function was found. And give
** priority to built-in functions.
**
** Except, if createFlag is true, that means that we are trying to
** install a new function. Whatever FuncDef structure is returned it will
** have fields overwritten with new information appropriate for the
** new function. But the FuncDefs for built-in functions are read-only.
** So we must not search for built-ins when creating a new function.
*/
if( !createFlag && (pBest==0 || (db->mDbFlags & DBFLAG_PreferBuiltin)!=0) ){
bestScore = 0;
h = (sqlite3UpperToLower[(u8)zName[0]] + nName) % SQLITE_FUNC_HASH_SZ;
p = functionSearch(h, zName);
while( p ){
int score = matchQuality(p, nArg, enc);
if( score>bestScore ){
pBest = p;
bestScore = score;
}
p = p->pNext;
}
}
/* If the createFlag parameter is true and the search did not reveal an
** exact match for the name, number of arguments and encoding, then add a
** new entry to the hash table and return it.
*/
if( createFlag && bestScore<FUNC_PERFECT_MATCH &&
(pBest = sqlite3DbMallocZero(db, sizeof(*pBest)+nName+1))!=0 ){
FuncDef *pOther;
pBest->zName = (const char*)&pBest[1];
pBest->nArg = (u16)nArg;
pBest->funcFlags = enc;
memcpy((char*)&pBest[1], zName, nName+1);
pOther = (FuncDef*)sqlite3HashInsert(&db->aFunc, pBest->zName, pBest);
if( pOther==pBest ){
sqlite3DbFree(db, pBest);
sqlite3OomFault(db);
return 0;
}else{
pBest->pNext = pOther;
}
}
if( pBest && (pBest->xSFunc || createFlag) ){
return pBest;
}
return 0;
}
/*
** Locate a user function given a name, a number of arguments and a flag
** indicating whether the function prefers UTF-16 over UTF-8. Return a
** pointer to the FuncDef structure that defines that function, or return
** NULL if the function does not exist.
**
** If the createFlag argument is true, then a new (blank) FuncDef
** structure is created and liked into the "db" structure if a
** no matching function previously existed. When createFlag is true
** and the nArg parameter is -1, then only a function that accepts
** any number of arguments will be returned.
**
** If createFlag is false and nArg is -1, then the first valid
** function found is returned. A function is valid if either xFunc
** or xStep is non-zero.
**
** If createFlag is false, then a function with the required name and
** number of arguments may be returned even if the eTextRep flag does not
** match that requested.
*/
FuncDef *sqlite3FindFunction(
sqlite3 *db, /* An open database */
const char *zName, /* Name of the function. Not null-terminated */
int nName, /* Number of characters in the name */
int nArg, /* Number of arguments. -1 means any number */
u8 enc, /* Preferred text encoding */
int createFlag /* Create new entry if true and does not otherwise exist */
){
FuncDef *p; /* Iterator variable */
FuncDef *pBest = 0; /* Best match found so far */
int bestScore = 0; /* Score of best match */
int h; /* Hash value */
assert( enc==SQLITE_UTF8 || enc==SQLITE_UTF16LE || enc==SQLITE_UTF16BE );
if( nArg<-1 ) nArg = -1;
h = (sqlite3UpperToLower[(u8)zName[0]] + nName) % ArraySize(db->aFunc.a);
/* First search for a match amongst the application-defined functions.
*/
p = functionSearch(&db->aFunc, h, zName, nName);
while( p ){
int score = matchQuality(p, nArg, enc);
if( score>bestScore ){
pBest = p;
bestScore = score;
}
p = p->pNext;
}
/* If no match is found, search the built-in functions.
**
** Except, if createFlag is true, that means that we are trying to
** install a new function. Whatever FuncDef structure is returned will
** have fields overwritten with new information appropriate for the
** new function. But the FuncDefs for built-in functions are read-only.
** So we must not search for built-ins when creating a new function.
*/
if( !createFlag && !pBest ){
FuncDefHash *pHash = &GLOBAL(FuncDefHash, sqlite3GlobalFunctions);
p = functionSearch(pHash, h, zName, nName);
while( p ){
int score = matchQuality(p, nArg, enc);
if( score>bestScore ){
pBest = p;
bestScore = score;
}
p = p->pNext;
}
}
/* If the createFlag parameter is true and the search did not reveal an
** exact match for the name, number of arguments and encoding, then add a
** new entry to the hash table and return it.
*/
if( createFlag && (bestScore<6 || pBest->nArg!=nArg) &&
(pBest = sqlite3DbMallocZero(db, sizeof(*pBest)+nName+1))!=0 ){
pBest->zName = (char *)&pBest[1];
pBest->nArg = (u16)nArg;
pBest->iPrefEnc = enc;
memcpy(pBest->zName, zName, nName);
pBest->zName[nName] = 0;
sqlite3FuncDefInsert(&db->aFunc, pBest);
}
if( pBest && (pBest->xStep || pBest->xFunc || createFlag) ){
return pBest;
}
return 0;
}
/*
** Execute SQL code. Return one of the SQLITE_ success/failure
** codes. Also write an error message into memory obtained from
** malloc() and make *pzErrMsg point to that message.
**
** If the SQL is a query, then for each row in the query result
** the xCallback() function is called. pArg becomes the first
** argument to xCallback(). If xCallback=NULL then no callback
** is invoked, even for queries.
*/
int sqlite3_exec(
sqlite3 *db, /* The database on which the SQL executes */
const char *zSql, /* The SQL to be executed */
sqlite3_callback xCallback, /* Invoke this callback routine */
void *pArg, /* First argument to xCallback() */
char **pzErrMsg /* Write error messages here */
){
int rc = SQLITE_OK; /* Return code */
const char *zLeftover; /* Tail of unprocessed SQL */
sqlite3_stmt *pStmt = 0; /* The current SQL statement */
char **azCols = 0; /* Names of result columns */
int nRetry = 0; /* Number of retry attempts */
int callbackIsInit; /* True if callback data is initialized */
if( !sqlite3SafetyCheckOk(db) ) return SQLITE_MISUSE_BKPT;
if( zSql==0 ) zSql = "";
#ifdef SQLITE_ENABLE_SQLRR
SRRecExec(db, zSql);
#endif
sqlite3_mutex_enter(db->mutex);
sqlite3Error(db, SQLITE_OK, 0);
while( (rc==SQLITE_OK || (rc==SQLITE_SCHEMA && (++nRetry)<2)) && zSql[0] ){
int nCol;
char **azVals = 0;
pStmt = 0;
rc = sqlite3_prepare(db, zSql, -1, &pStmt, &zLeftover);
assert( rc==SQLITE_OK || pStmt==0 );
if( rc!=SQLITE_OK ){
continue;
}
if( !pStmt ){
/* this happens for a comment or white-space */
zSql = zLeftover;
continue;
}
callbackIsInit = 0;
nCol = sqlite3_column_count(pStmt);
while( 1 ){
int i;
rc = sqlite3_step(pStmt);
/* Invoke the callback function if required */
if( xCallback && (SQLITE_ROW==rc ||
(SQLITE_DONE==rc && !callbackIsInit
&& db->flags&SQLITE_NullCallback)) ){
if( !callbackIsInit ){
azCols = sqlite3DbMallocZero(db, 2*nCol*sizeof(const char*) + 1);
if( azCols==0 ){
goto exec_out;
}
for(i=0; i<nCol; i++){
azCols[i] = (char *)sqlite3_column_name(pStmt, i);
/* sqlite3VdbeSetColName() installs column names as UTF8
** strings so there is no way for sqlite3_column_name() to fail. */
assert( azCols[i]!=0 );
}
callbackIsInit = 1;
}
if( rc==SQLITE_ROW ){
azVals = &azCols[nCol];
for(i=0; i<nCol; i++){
azVals[i] = (char *)sqlite3_column_text(pStmt, i);
if( !azVals[i] && sqlite3_column_type(pStmt, i)!=SQLITE_NULL ){
db->mallocFailed = 1;
goto exec_out;
}
}
}
if( xCallback(pArg, nCol, azVals, azCols) ){
rc = SQLITE_ABORT;
sqlite3VdbeFinalize((Vdbe *)pStmt);
pStmt = 0;
sqlite3Error(db, SQLITE_ABORT, 0);
goto exec_out;
}
}
if( rc!=SQLITE_ROW ){
rc = sqlite3VdbeFinalize((Vdbe *)pStmt);
pStmt = 0;
if( rc!=SQLITE_SCHEMA ){
nRetry = 0;
zSql = zLeftover;
while( sqlite3Isspace(zSql[0]) ) zSql++;
}
break;
}
}
sqlite3DbFree(db, azCols);
azCols = 0;
}
exec_out:
if( pStmt ) sqlite3VdbeFinalize((Vdbe *)pStmt);
sqlite3DbFree(db, azCols);
#ifdef SQLITE_ENABLE_SQLRR
SRRecExecEnd(db);
#endif
rc = sqlite3ApiExit(db, rc);
if( rc!=SQLITE_OK && ALWAYS(rc==sqlite3_errcode(db)) && pzErrMsg ){
int nErrMsg = 1 + sqlite3Strlen30(sqlite3_errmsg(db));
*pzErrMsg = sqlite3Malloc(nErrMsg);
if( *pzErrMsg ){
memcpy(*pzErrMsg, sqlite3_errmsg(db), nErrMsg);
}else{
rc = SQLITE_NOMEM;
sqlite3Error(db, SQLITE_NOMEM, 0);
}
}else if( pzErrMsg ){
*pzErrMsg = 0;
}
assert( (rc&db->errMask)==rc );
sqlite3_mutex_leave(db->mutex);
return rc;
}
/*
** Locate a user function given a name, a number of arguments and a flag
** indicating whether the function prefers UTF-16 over UTF-8. Return a
** pointer to the FuncDef structure that defines that function, or return
** NULL if the function does not exist.
**
** If the createFlag argument is true, then a new (blank) FuncDef
** structure is created and liked into the "db" structure if a
** no matching function previously existed. When createFlag is true
** and the nArg parameter is -1, then only a function that accepts
** any number of arguments will be returned.
**
** If createFlag is false and nArg is -1, then the first valid
** function found is returned. A function is valid if either xFunc
** or xStep is non-zero.
**
** If createFlag is false, then a function with the required name and
** number of arguments may be returned even if the eTextRep flag does not
** match that requested.
*/
FuncDef *sqlite3FindFunction(
sqlite3 *db, /* An open database */
const char *zName, /* Name of the function. Not null-terminated */
int nName, /* Number of characters in the name */
int nArg, /* Number of arguments. -1 means any number */
u8 enc, /* Preferred text encoding */
int createFlag /* Create new entry if true and does not otherwise exist */
){
FuncDef *p; /* Iterator variable */
FuncDef *pFirst; /* First function with this name */
FuncDef *pBest = 0; /* Best match found so far */
int bestmatch = 0;
assert( enc==SQLITE_UTF8 || enc==SQLITE_UTF16LE || enc==SQLITE_UTF16BE );
if( nArg<-1 ) nArg = -1;
pFirst = (FuncDef*)sqlite3HashFind(&db->aFunc, zName, nName);
for(p=pFirst; p; p=p->pNext){
/* During the search for the best function definition, bestmatch is set
** as follows to indicate the quality of the match with the definition
** pointed to by pBest:
**
** 0: pBest is NULL. No match has been found.
** 1: A variable arguments function that prefers UTF-8 when a UTF-16
** encoding is requested, or vice versa.
** 2: A variable arguments function that uses UTF-16BE when UTF-16LE is
** requested, or vice versa.
** 3: A variable arguments function using the same text encoding.
** 4: A function with the exact number of arguments requested that
** prefers UTF-8 when a UTF-16 encoding is requested, or vice versa.
** 5: A function with the exact number of arguments requested that
** prefers UTF-16LE when UTF-16BE is requested, or vice versa.
** 6: An exact match.
**
** A larger value of 'matchqual' indicates a more desirable match.
*/
if( p->nArg==-1 || p->nArg==nArg || nArg==-1 ){
int match = 1; /* Quality of this match */
if( p->nArg==nArg || nArg==-1 ){
match = 4;
}
if( enc==p->iPrefEnc ){
match += 2;
}
else if( (enc==SQLITE_UTF16LE && p->iPrefEnc==SQLITE_UTF16BE) ||
(enc==SQLITE_UTF16BE && p->iPrefEnc==SQLITE_UTF16LE) ){
match += 1;
}
if( match>bestmatch ){
pBest = p;
bestmatch = match;
}
}
}
/* If the createFlag parameter is true, and the seach did not reveal an
** exact match for the name, number of arguments and encoding, then add a
** new entry to the hash table and return it.
*/
if( createFlag && bestmatch<6 &&
(pBest = sqlite3DbMallocZero(db, sizeof(*pBest)+nName))!=0 ){
pBest->nArg = nArg;
pBest->pNext = pFirst;
pBest->iPrefEnc = enc;
memcpy(pBest->zName, zName, nName);
pBest->zName[nName] = 0;
if( pBest==sqlite3HashInsert(&db->aFunc,pBest->zName,nName,(void*)pBest) ){
db->mallocFailed = 1;
sqlite3DbFree(db, pBest);
return 0;
}
}
if( pBest && (pBest->xStep || pBest->xFunc || createFlag) ){
return pBest;
}
return 0;
}
/*
** This is called by the parser when it sees a CREATE TRIGGER statement
** up to the point of the BEGIN before the trigger actions. A Trigger
** structure is generated based on the information available and stored
** in pParse->pNewTrigger. After the trigger actions have been parsed, the
** sqlite3FinishTrigger() function is called to complete the trigger
** construction process.
*/
void sqlite3BeginTrigger(
Parse *pParse, /* The parse context of the CREATE TRIGGER statement */
Token *pName1, /* The name of the trigger */
Token *pName2, /* The name of the trigger */
int tr_tm, /* One of TK_BEFORE, TK_AFTER, TK_INSTEAD */
int op, /* One of TK_INSERT, TK_UPDATE, TK_DELETE */
IdList *pColumns, /* column list if this is an UPDATE OF trigger */
SrcList *pTableName,/* The name of the table/view the trigger applies to */
Expr *pWhen, /* WHEN clause */
int isTemp, /* True if the TEMPORARY keyword is present */
int noErr /* Suppress errors if the trigger already exists */
){
Trigger *pTrigger = 0;
Table *pTab;
char *zName = 0; /* Name of the trigger */
sqlite3 *db = pParse->db;
int iDb; /* The database to store the trigger in */
Token *pName; /* The unqualified db name */
DbFixer sFix;
int iTabDb;
assert( pName1!=0 ); /* pName1->z might be NULL, but not pName1 itself */
assert( pName2!=0 );
if( isTemp ){
/* If TEMP was specified, then the trigger name may not be qualified. */
if( pName2->n>0 ){
sqlite3ErrorMsg(pParse, "temporary trigger may not have qualified name");
goto trigger_cleanup;
}
iDb = 1;
pName = pName1;
}else{
/* Figure out the db that the the trigger will be created in */
iDb = sqlite3TwoPartName(pParse, pName1, pName2, &pName);
if( iDb<0 ){
goto trigger_cleanup;
}
}
/* If the trigger name was unqualified, and the table is a temp table,
** then set iDb to 1 to create the trigger in the temporary database.
** If sqlite3SrcListLookup() returns 0, indicating the table does not
** exist, the error is caught by the block below.
*/
if( !pTableName || db->mallocFailed ){
goto trigger_cleanup;
}
pTab = sqlite3SrcListLookup(pParse, pTableName);
if( pName2->n==0 && pTab && pTab->pSchema==db->aDb[1].pSchema ){
iDb = 1;
}
/* Ensure the table name matches database name and that the table exists */
if( db->mallocFailed ) goto trigger_cleanup;
assert( pTableName->nSrc==1 );
if( sqlite3FixInit(&sFix, pParse, iDb, "trigger", pName) &&
sqlite3FixSrcList(&sFix, pTableName) ){
goto trigger_cleanup;
}
pTab = sqlite3SrcListLookup(pParse, pTableName);
if( !pTab ){
/* The table does not exist. */
goto trigger_cleanup;
}
if( IsVirtual(pTab) ){
sqlite3ErrorMsg(pParse, "cannot create triggers on virtual tables");
goto trigger_cleanup;
}
/* Check that the trigger name is not reserved and that no trigger of the
** specified name exists */
zName = sqlite3NameFromToken(db, pName);
if( !zName || SQLITE_OK!=sqlite3CheckObjectName(pParse, zName) ){
goto trigger_cleanup;
}
if( sqlite3HashFind(&(db->aDb[iDb].pSchema->trigHash), zName,strlen(zName)) ){
if( !noErr ){
sqlite3ErrorMsg(pParse, "trigger %T already exists", pName);
}
goto trigger_cleanup;
}
/* Do not create a trigger on a system table */
if( sqlite3StrNICmp(pTab->zName, "sqlite_", 7)==0 ){
sqlite3ErrorMsg(pParse, "cannot create trigger on system table");
pParse->nErr++;
goto trigger_cleanup;
}
/* INSTEAD of triggers are only for views and views only support INSTEAD
** of triggers.
*/
if( pTab->pSelect && tr_tm!=TK_INSTEAD ){
sqlite3ErrorMsg(pParse, "cannot create %s trigger on view: %S",
(tr_tm == TK_BEFORE)?"BEFORE":"AFTER", pTableName, 0);
goto trigger_cleanup;
}
if( !pTab->pSelect && tr_tm==TK_INSTEAD ){
sqlite3ErrorMsg(pParse, "cannot create INSTEAD OF"
" trigger on table: %S", pTableName, 0);
goto trigger_cleanup;
}
iTabDb = sqlite3SchemaToIndex(db, pTab->pSchema);
#ifndef SQLITE_OMIT_AUTHORIZATION
{
int code = SQLITE_CREATE_TRIGGER;
const char *zDb = db->aDb[iTabDb].zName;
const char *zDbTrig = isTemp ? db->aDb[1].zName : zDb;
if( iTabDb==1 || isTemp ) code = SQLITE_CREATE_TEMP_TRIGGER;
if( sqlite3AuthCheck(pParse, code, zName, pTab->zName, zDbTrig) ){
goto trigger_cleanup;
}
if( sqlite3AuthCheck(pParse, SQLITE_INSERT, SCHEMA_TABLE(iTabDb),0,zDb)){
goto trigger_cleanup;
}
}
#endif
/* INSTEAD OF triggers can only appear on views and BEFORE triggers
** cannot appear on views. So we might as well translate every
** INSTEAD OF trigger into a BEFORE trigger. It simplifies code
** elsewhere.
*/
if (tr_tm == TK_INSTEAD){
tr_tm = TK_BEFORE;
}
/* Build the Trigger object */
pTrigger = (Trigger*)sqlite3DbMallocZero(db, sizeof(Trigger));
if( pTrigger==0 ) goto trigger_cleanup;
pTrigger->name = zName;
zName = 0;
pTrigger->table = sqlite3DbStrDup(db, pTableName->a[0].zName);
pTrigger->pSchema = db->aDb[iDb].pSchema;
pTrigger->pTabSchema = pTab->pSchema;
pTrigger->op = op;
pTrigger->tr_tm = tr_tm==TK_BEFORE ? TRIGGER_BEFORE : TRIGGER_AFTER;
pTrigger->pWhen = sqlite3ExprDup(db, pWhen);
pTrigger->pColumns = sqlite3IdListDup(db, pColumns);
sqlite3TokenCopy(db, &pTrigger->nameToken,pName);
assert( pParse->pNewTrigger==0 );
pParse->pNewTrigger = pTrigger;
trigger_cleanup:
sqlite3_free(zName);
sqlite3SrcListDelete(pTableName);
sqlite3IdListDelete(pColumns);
sqlite3ExprDelete(pWhen);
if( !pParse->pNewTrigger ){
sqlite3DeleteTrigger(pTrigger);
}else{
assert( pParse->pNewTrigger==pTrigger );
}
}
/*
** Attempt to load an SQLite extension library contained in the file
** zFile. The entry point is zProc. zProc may be 0 in which case a
** default entry point name (sqlite3_extension_init) is used. Use
** of the default name is recommended.
**
** Return SQLITE_OK on success and SQLITE_ERROR if something goes wrong.
**
** If an error occurs and pzErrMsg is not 0, then fill *pzErrMsg with
** error message text. The calling function should free this memory
** by calling sqlite3DbFree(db, ).
*/
static int sqlite3LoadExtension(
sqlite3 *db, /* Load the extension into this database connection */
const char *zFile, /* Name of the shared library containing extension */
const char *zProc, /* Entry point. Use "sqlite3_extension_init" if 0 */
char **pzErrMsg /* Put error message here if not 0 */
){
sqlite3_vfs *pVfs = db->pVfs;
void *handle;
int (*xInit)(sqlite3*,char**,const sqlite3_api_routines*);
char *zErrmsg = 0;
const char *zEntry;
char *zAltEntry = 0;
void **aHandle;
int nMsg = 300 + sqlite3Strlen30(zFile);
int ii;
/* Shared library endings to try if zFile cannot be loaded as written */
static const char *azEndings[] = {
#if SQLITE_OS_WIN
"dll"
#elif defined(__APPLE__)
"dylib"
#else
"so"
#endif
};
if( pzErrMsg ) *pzErrMsg = 0;
/* Ticket #1863. To avoid a creating security problems for older
** applications that relink against newer versions of SQLite, the
** ability to run load_extension is turned off by default. One
** must call sqlite3_enable_load_extension() to turn on extension
** loading. Otherwise you get the following error.
*/
if( (db->flags & SQLITE_LoadExtension)==0 ){
if( pzErrMsg ){
*pzErrMsg = sqlite3_mprintf("not authorized");
}
return SQLITE_ERROR;
}
zEntry = zProc ? zProc : "sqlite3_extension_init";
handle = sqlite3OsDlOpen(pVfs, zFile);
#if SQLITE_OS_UNIX || SQLITE_OS_WIN
for(ii=0; ii<ArraySize(azEndings) && handle==0; ii++){
char *zAltFile = sqlite3_mprintf("%s.%s", zFile, azEndings[ii]);
if( zAltFile==0 ) return SQLITE_NOMEM;
handle = sqlite3OsDlOpen(pVfs, zAltFile);
sqlite3_free(zAltFile);
}
#endif
if( handle==0 ){
if( pzErrMsg ){
*pzErrMsg = zErrmsg = sqlite3_malloc(nMsg);
if( zErrmsg ){
sqlite3_snprintf(nMsg, zErrmsg,
"unable to open shared library [%s]", zFile);
sqlite3OsDlError(pVfs, nMsg-1, zErrmsg);
}
}
return SQLITE_ERROR;
}
xInit = (int(*)(sqlite3*,char**,const sqlite3_api_routines*))
sqlite3OsDlSym(pVfs, handle, zEntry);
/* If no entry point was specified and the default legacy
** entry point name "sqlite3_extension_init" was not found, then
** construct an entry point name "sqlite3_X_init" where the X is
** replaced by the lowercase value of every ASCII alphabetic
** character in the filename after the last "/" upto the first ".",
** and eliding the first three characters if they are "lib".
** Examples:
**
** /usr/local/lib/libExample5.4.3.so ==> sqlite3_example_init
** C:/lib/mathfuncs.dll ==> sqlite3_mathfuncs_init
*/
if( xInit==0 && zProc==0 ){
int iFile, iEntry, c;
int ncFile = sqlite3Strlen30(zFile);
zAltEntry = sqlite3_malloc(ncFile+30);
if( zAltEntry==0 ){
sqlite3OsDlClose(pVfs, handle);
return SQLITE_NOMEM;
}
memcpy(zAltEntry, "sqlite3_", 8);
for(iFile=ncFile-1; iFile>=0 && zFile[iFile]!='/'; iFile--){}
iFile++;
if( sqlite3_strnicmp(zFile+iFile, "lib", 3)==0 ) iFile += 3;
for(iEntry=8; (c = zFile[iFile])!=0 && c!='.'; iFile++){
if( sqlite3Isalpha(c) ){
zAltEntry[iEntry++] = (char)sqlite3UpperToLower[(unsigned)c];
}
}
memcpy(zAltEntry+iEntry, "_init", 6);
zEntry = zAltEntry;
xInit = (int(*)(sqlite3*,char**,const sqlite3_api_routines*))
sqlite3OsDlSym(pVfs, handle, zEntry);
}
if( xInit==0 ){
if( pzErrMsg ){
nMsg += sqlite3Strlen30(zEntry);
*pzErrMsg = zErrmsg = sqlite3_malloc(nMsg);
if( zErrmsg ){
sqlite3_snprintf(nMsg, zErrmsg,
"no entry point [%s] in shared library [%s]", zEntry, zFile);
sqlite3OsDlError(pVfs, nMsg-1, zErrmsg);
}
}
sqlite3OsDlClose(pVfs, handle);
sqlite3_free(zAltEntry);
return SQLITE_ERROR;
}
sqlite3_free(zAltEntry);
if( xInit(db, &zErrmsg, &sqlite3Apis) ){
if( pzErrMsg ){
*pzErrMsg = sqlite3_mprintf("error during initialization: %s", zErrmsg);
}
sqlite3_free(zErrmsg);
sqlite3OsDlClose(pVfs, handle);
return SQLITE_ERROR;
}
/* Append the new shared library handle to the db->aExtension array. */
aHandle = sqlite3DbMallocZero(db, sizeof(handle)*(db->nExtension+1));
if( aHandle==0 ){
return SQLITE_NOMEM;
}
if( db->nExtension>0 ){
memcpy(aHandle, db->aExtension, sizeof(handle)*db->nExtension);
}
sqlite3DbFree(db, db->aExtension);
db->aExtension = aHandle;
db->aExtension[db->nExtension++] = handle;
return SQLITE_OK;
}
/*
** Open a blob handle.
*/
int sqlite3_blob_open(
sqlite3* db, /* The database connection */
const char *zDb, /* The attached database containing the blob */
const char *zTable, /* The table containing the blob */
const char *zColumn, /* The column containing the blob */
sqlite_int64 iRow, /* The row containing the glob */
int flags, /* True -> read/write access, false -> read-only */
sqlite3_blob **ppBlob /* Handle for accessing the blob returned here */
){
int nAttempt = 0;
int iCol; /* Index of zColumn in row-record */
/* This VDBE program seeks a btree cursor to the identified
** db/table/row entry. The reason for using a vdbe program instead
** of writing code to use the b-tree layer directly is that the
** vdbe program will take advantage of the various transaction,
** locking and error handling infrastructure built into the vdbe.
**
** After seeking the cursor, the vdbe executes an OP_ResultRow.
** Code external to the Vdbe then "borrows" the b-tree cursor and
** uses it to implement the blob_read(), blob_write() and
** blob_bytes() functions.
**
** The sqlite3_blob_close() function finalizes the vdbe program,
** which closes the b-tree cursor and (possibly) commits the
** transaction.
*/
static const VdbeOpList openBlob[] = {
{OP_Transaction, 0, 0, 0}, /* 0: Start a transaction */
{OP_VerifyCookie, 0, 0, 0}, /* 1: Check the schema cookie */
{OP_TableLock, 0, 0, 0}, /* 2: Acquire a read or write lock */
/* One of the following two instructions is replaced by an OP_Noop. */
{OP_OpenRead, 0, 0, 0}, /* 3: Open cursor 0 for reading */
{OP_OpenWrite, 0, 0, 0}, /* 4: Open cursor 0 for read/write */
{OP_Variable, 1, 1, 1}, /* 5: Push the rowid to the stack */
{OP_NotExists, 0, 9, 1}, /* 6: Seek the cursor */
{OP_Column, 0, 0, 1}, /* 7 */
{OP_ResultRow, 1, 0, 0}, /* 8 */
{OP_Close, 0, 0, 0}, /* 9 */
{OP_Halt, 0, 0, 0}, /* 10 */
};
Vdbe *v = 0;
int rc = SQLITE_OK;
char *zErr = 0;
Table *pTab;
Parse *pParse;
*ppBlob = 0;
sqlite3_mutex_enter(db->mutex);
pParse = sqlite3StackAllocRaw(db, sizeof(*pParse));
if( pParse==0 ){
rc = SQLITE_NOMEM;
goto blob_open_out;
}
do {
memset(pParse, 0, sizeof(Parse));
pParse->db = db;
if( sqlite3SafetyOn(db) ){
sqlite3DbFree(db, zErr);
sqlite3StackFree(db, pParse);
sqlite3_mutex_leave(db->mutex);
return SQLITE_MISUSE;
}
sqlite3BtreeEnterAll(db);
pTab = sqlite3LocateTable(pParse, 0, zTable, zDb);
if( pTab && IsVirtual(pTab) ){
pTab = 0;
sqlite3ErrorMsg(pParse, "cannot open virtual table: %s", zTable);
}
#ifndef SQLITE_OMIT_VIEW
if( pTab && pTab->pSelect ){
pTab = 0;
sqlite3ErrorMsg(pParse, "cannot open view: %s", zTable);
}
#endif
if( !pTab ){
if( pParse->zErrMsg ){
sqlite3DbFree(db, zErr);
zErr = pParse->zErrMsg;
pParse->zErrMsg = 0;
}
rc = SQLITE_ERROR;
(void)sqlite3SafetyOff(db);
sqlite3BtreeLeaveAll(db);
goto blob_open_out;
}
/* Now search pTab for the exact column. */
for(iCol=0; iCol < pTab->nCol; iCol++) {
if( sqlite3StrICmp(pTab->aCol[iCol].zName, zColumn)==0 ){
break;
}
}
if( iCol==pTab->nCol ){
sqlite3DbFree(db, zErr);
zErr = sqlite3MPrintf(db, "no such column: \"%s\"", zColumn);
rc = SQLITE_ERROR;
(void)sqlite3SafetyOff(db);
sqlite3BtreeLeaveAll(db);
goto blob_open_out;
}
/* If the value is being opened for writing, check that the
** column is not indexed. It is against the rules to open an
** indexed column for writing.
*/
if( flags ){
Index *pIdx;
for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
int j;
for(j=0; j<pIdx->nColumn; j++){
if( pIdx->aiColumn[j]==iCol ){
sqlite3DbFree(db, zErr);
zErr = sqlite3MPrintf(db,
"cannot open indexed column for writing");
rc = SQLITE_ERROR;
(void)sqlite3SafetyOff(db);
sqlite3BtreeLeaveAll(db);
goto blob_open_out;
}
}
}
}
v = sqlite3VdbeCreate(db);
if( v ){
int iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
sqlite3VdbeAddOpList(v, sizeof(openBlob)/sizeof(VdbeOpList), openBlob);
flags = !!flags; /* flags = (flags ? 1 : 0); */
/* Configure the OP_Transaction */
sqlite3VdbeChangeP1(v, 0, iDb);
sqlite3VdbeChangeP2(v, 0, flags);
/* Configure the OP_VerifyCookie */
sqlite3VdbeChangeP1(v, 1, iDb);
sqlite3VdbeChangeP2(v, 1, pTab->pSchema->schema_cookie);
/* Make sure a mutex is held on the table to be accessed */
sqlite3VdbeUsesBtree(v, iDb);
/* Configure the OP_TableLock instruction */
sqlite3VdbeChangeP1(v, 2, iDb);
sqlite3VdbeChangeP2(v, 2, pTab->tnum);
sqlite3VdbeChangeP3(v, 2, flags);
sqlite3VdbeChangeP4(v, 2, pTab->zName, P4_TRANSIENT);
/* Remove either the OP_OpenWrite or OpenRead. Set the P2
** parameter of the other to pTab->tnum. */
sqlite3VdbeChangeToNoop(v, 4 - flags, 1);
sqlite3VdbeChangeP2(v, 3 + flags, pTab->tnum);
sqlite3VdbeChangeP3(v, 3 + flags, iDb);
/* Configure the number of columns. Configure the cursor to
** think that the table has one more column than it really
** does. An OP_Column to retrieve this imaginary column will
** always return an SQL NULL. This is useful because it means
** we can invoke OP_Column to fill in the vdbe cursors type
** and offset cache without causing any IO.
*/
sqlite3VdbeChangeP4(v, 3+flags, SQLITE_INT_TO_PTR(pTab->nCol+1),P4_INT32);
sqlite3VdbeChangeP2(v, 7, pTab->nCol);
if( !db->mallocFailed ){
sqlite3VdbeMakeReady(v, 1, 1, 1, 0);
}
}
sqlite3BtreeLeaveAll(db);
rc = sqlite3SafetyOff(db);
if( NEVER(rc!=SQLITE_OK) || db->mallocFailed ){
goto blob_open_out;
}
sqlite3_bind_int64((sqlite3_stmt *)v, 1, iRow);
rc = sqlite3_step((sqlite3_stmt *)v);
if( rc!=SQLITE_ROW ){
nAttempt++;
rc = sqlite3_finalize((sqlite3_stmt *)v);
sqlite3DbFree(db, zErr);
zErr = sqlite3MPrintf(db, sqlite3_errmsg(db));
v = 0;
}
} while( nAttempt<5 && rc==SQLITE_SCHEMA );
if( rc==SQLITE_ROW ){
/* The row-record has been opened successfully. Check that the
** column in question contains text or a blob. If it contains
** text, it is up to the caller to get the encoding right.
*/
Incrblob *pBlob;
u32 type = v->apCsr[0]->aType[iCol];
if( type<12 ){
sqlite3DbFree(db, zErr);
zErr = sqlite3MPrintf(db, "cannot open value of type %s",
type==0?"null": type==7?"real": "integer"
);
rc = SQLITE_ERROR;
goto blob_open_out;
}
pBlob = (Incrblob *)sqlite3DbMallocZero(db, sizeof(Incrblob));
if( db->mallocFailed ){
sqlite3DbFree(db, pBlob);
goto blob_open_out;
}
pBlob->flags = flags;
pBlob->pCsr = v->apCsr[0]->pCursor;
sqlite3BtreeEnterCursor(pBlob->pCsr);
sqlite3BtreeCacheOverflow(pBlob->pCsr);
sqlite3BtreeLeaveCursor(pBlob->pCsr);
pBlob->pStmt = (sqlite3_stmt *)v;
pBlob->iOffset = v->apCsr[0]->aOffset[iCol];
pBlob->nByte = sqlite3VdbeSerialTypeLen(type);
pBlob->db = db;
*ppBlob = (sqlite3_blob *)pBlob;
rc = SQLITE_OK;
}else if( rc==SQLITE_OK ){
sqlite3DbFree(db, zErr);
zErr = sqlite3MPrintf(db, "no such rowid: %lld", iRow);
rc = SQLITE_ERROR;
}
blob_open_out:
if( v && (rc!=SQLITE_OK || db->mallocFailed) ){
sqlite3VdbeFinalize(v);
}
sqlite3Error(db, rc, zErr);
sqlite3DbFree(db, zErr);
sqlite3StackFree(db, pParse);
rc = sqlite3ApiExit(db, rc);
sqlite3_mutex_leave(db->mutex);
return rc;
}
/*
** This function is called by the parser after the table-name in
** an "ALTER TABLE <table-name> ADD" statement is parsed. Argument
** pSrc is the full-name of the table being altered.
**
** This routine makes a (partial) copy of the Table structure
** for the table being altered and sets Parse.pNewTable to point
** to it. Routines called by the parser as the column definition
** is parsed (i.e. sqlite3AddColumn()) add the new Column data to
** the copy. The copy of the Table structure is deleted by tokenize.c
** after parsing is finished.
**
** Routine sqlite3AlterFinishAddColumn() will be called to complete
** coding the "ALTER TABLE ... ADD" statement.
*/
void sqlite3AlterBeginAddColumn(Parse *pParse, SrcList *pSrc){
Table *pNew;
Table *pTab;
Vdbe *v;
int iDb;
int i;
int nAlloc;
sqlite3 *db = pParse->db;
/* Look up the table being altered. */
assert( pParse->pNewTable==0 );
assert( sqlite3BtreeHoldsAllMutexes(db) );
if( db->mallocFailed ) goto exit_begin_add_column;
pTab = sqlite3LocateTable(pParse, 0, pSrc->a[0].zName, pSrc->a[0].zDatabase);
if( !pTab ) goto exit_begin_add_column;
#ifndef SQLITE_OMIT_VIRTUALTABLE
if( IsVirtual(pTab) ){
sqlite3ErrorMsg(pParse, "virtual tables may not be altered");
goto exit_begin_add_column;
}
#endif
/* Make sure this is not an attempt to ALTER a view. */
if( pTab->pSelect ){
sqlite3ErrorMsg(pParse, "Cannot add a column to a view");
goto exit_begin_add_column;
}
assert( pTab->addColOffset>0 );
iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
/* Put a copy of the Table struct in Parse.pNewTable for the
** sqlite3AddColumn() function and friends to modify. But modify
** the name by adding an "sqlite_altertab_" prefix. By adding this
** prefix, we insure that the name will not collide with an existing
** table because user table are not allowed to have the "sqlite_"
** prefix on their name.
*/
pNew = (Table*)sqlite3DbMallocZero(db, sizeof(Table));
if( !pNew ) goto exit_begin_add_column;
pParse->pNewTable = pNew;
pNew->nRef = 1;
pNew->db = db;
pNew->nCol = pTab->nCol;
assert( pNew->nCol>0 );
nAlloc = (((pNew->nCol-1)/8)*8)+8;
assert( nAlloc>=pNew->nCol && nAlloc%8==0 && nAlloc-pNew->nCol<8 );
pNew->aCol = (Column*)sqlite3DbMallocZero(db, sizeof(Column)*nAlloc);
pNew->zName = sqlite3MPrintf(db, "sqlite_altertab_%s", pTab->zName);
if( !pNew->aCol || !pNew->zName ){
db->mallocFailed = 1;
goto exit_begin_add_column;
}
memcpy(pNew->aCol, pTab->aCol, sizeof(Column)*pNew->nCol);
for(i=0; i<pNew->nCol; i++){
Column *pCol = &pNew->aCol[i];
pCol->zName = sqlite3DbStrDup(db, pCol->zName);
pCol->zColl = 0;
pCol->zType = 0;
pCol->pDflt = 0;
}
pNew->pSchema = db->aDb[iDb].pSchema;
pNew->addColOffset = pTab->addColOffset;
pNew->nRef = 1;
/* Begin a transaction and increment the schema cookie. */
sqlite3BeginWriteOperation(pParse, 0, iDb);
v = sqlite3GetVdbe(pParse);
if( !v ) goto exit_begin_add_column;
sqlite3ChangeCookie(pParse, iDb);
exit_begin_add_column:
sqlite3SrcListDelete(db, pSrc);
return;
}
/*
** Attempt to load an SQLite extension library contained in the file
** zFile. The entry point is zProc. zProc may be 0 in which case a
** default entry point name (sqlite3_extension_init) is used. Use
** of the default name is recommended.
**
** Return SQLITE_OK on success and SQLITE_ERROR if something goes wrong.
**
** If an error occurs and pzErrMsg is not 0, then fill *pzErrMsg with
** error message text. The calling function should free this memory
** by calling sqlite3DbFree(db, ).
*/
static int sqlite3LoadExtension(
sqlite3 *db, /* Load the extension into this database connection */
const char *zFile, /* Name of the shared library containing extension */
const char *zProc, /* Entry point. Use "sqlite3_extension_init" if 0 */
char **pzErrMsg /* Put error message here if not 0 */
){
sqlite3_vfs *pVfs = db->pVfs;
void *handle;
int (*xInit)(sqlite3*,char**,const sqlite3_api_routines*);
char *zErrmsg = 0;
void **aHandle;
int nMsg = 300 + sqlite3Strlen30(zFile);
if( pzErrMsg ) *pzErrMsg = 0;
/* Ticket #1863. To avoid a creating security problems for older
** applications that relink against newer versions of SQLite, the
** ability to run load_extension is turned off by default. One
** must call sqlite3_enable_load_extension() to turn on extension
** loading. Otherwise you get the following error.
*/
if( (db->flags & SQLITE_LoadExtension)==0 ){
if( pzErrMsg ){
*pzErrMsg = sqlite3_mprintf("not authorized");
}
return SQLITE_ERROR;
}
if( zProc==0 ){
zProc = "sqlite3_extension_init";
}
handle = sqlite3OsDlOpen(pVfs, zFile);
if( handle==0 ){
if( pzErrMsg ){
*pzErrMsg = zErrmsg = sqlite3_malloc(nMsg);
if( zErrmsg ){
sqlite3_snprintf(nMsg, zErrmsg,
"unable to open shared library [%s]", zFile);
sqlite3OsDlError(pVfs, nMsg-1, zErrmsg);
}
}
return SQLITE_ERROR;
}
xInit = (int(*)(sqlite3*,char**,const sqlite3_api_routines*))
sqlite3OsDlSym(pVfs, handle, zProc);
if( xInit==0 ){
if( pzErrMsg ){
nMsg += sqlite3Strlen30(zProc);
*pzErrMsg = zErrmsg = sqlite3_malloc(nMsg);
if( zErrmsg ){
sqlite3_snprintf(nMsg, zErrmsg,
"no entry point [%s] in shared library [%s]", zProc,zFile);
sqlite3OsDlError(pVfs, nMsg-1, zErrmsg);
}
sqlite3OsDlClose(pVfs, handle);
}
return SQLITE_ERROR;
}else if( xInit(db, &zErrmsg, &sqlite3Apis) ){
if( pzErrMsg ){
*pzErrMsg = sqlite3_mprintf("error during initialization: %s", zErrmsg);
}
sqlite3_free(zErrmsg);
sqlite3OsDlClose(pVfs, handle);
return SQLITE_ERROR;
}
/* Append the new shared library handle to the db->aExtension array. */
aHandle = sqlite3DbMallocZero(db, sizeof(handle)*(db->nExtension+1));
if( aHandle==0 ){
return SQLITE_NOMEM;
}
if( db->nExtension>0 ){
memcpy(aHandle, db->aExtension, sizeof(handle)*db->nExtension);
}
sqlite3DbFree(db, db->aExtension);
db->aExtension = aHandle;
db->aExtension[db->nExtension++] = handle;
return SQLITE_OK;
}
/*
** This is called by the parser when it sees a CREATE TRIGGER statement
** up to the point of the BEGIN before the trigger actions. A Trigger
** structure is generated based on the information available and stored
** in pParse->pNewTrigger. After the trigger actions have been parsed, the
** sqlite3FinishTrigger() function is called to complete the trigger
** construction process.
*/
SQLITE_PRIVATE void sqlite3BeginTrigger(
Parse *pParse, /* The parse context of the CREATE TRIGGER statement */
Token *pName1, /* The name of the trigger */
Token *pName2, /* The name of the trigger */
int tr_tm, /* One of TK_BEFORE, TK_AFTER, TK_INSTEAD */
int op, /* One of TK_INSERT, TK_UPDATE, TK_DELETE */
IdList *pColumns, /* column list if this is an UPDATE OF trigger */
SrcList *pTableName,/* The name of the table/view the trigger applies to */
Expr *pWhen, /* WHEN clause */
int isTemp, /* True if the TEMPORARY keyword is present */
int noErr /* Suppress errors if the trigger already exists */
){
Trigger *pTrigger = 0; /* The new trigger */
Table *pTab; /* Table that the trigger fires off of */
char *zName = 0; /* Name of the trigger */
sqlite3 *db = pParse->db; /* The database connection */
int iDb; /* The database to store the trigger in */
Token *pName; /* The unqualified db name */
DbFixer sFix; /* State vector for the DB fixer */
int iTabDb; /* Index of the database holding pTab */
assert( pName1!=0 ); /* pName1->z might be NULL, but not pName1 itself */
assert( pName2!=0 );
assert( op==TK_INSERT || op==TK_UPDATE || op==TK_DELETE );
assert( op>0 && op<0xff );
if( isTemp ){
/* If TEMP was specified, then the trigger name may not be qualified. */
if( pName2->n>0 ){
sqlite3ErrorMsg(pParse, "temporary trigger may not have qualified name");
goto trigger_cleanup;
}
iDb = 1;
pName = pName1;
}else{
/* Figure out the db that the trigger will be created in */
iDb = sqlite3TwoPartName(pParse, pName1, pName2, &pName);
if( iDb<0 ){
goto trigger_cleanup;
}
}
if( !pTableName || db->mallocFailed ){
goto trigger_cleanup;
}
/* A long-standing parser bug is that this syntax was allowed:
**
** CREATE TRIGGER attached.demo AFTER INSERT ON attached.tab ....
** ^^^^^^^^
**
** To maintain backwards compatibility, ignore the database
** name on pTableName if we are reparsing our of SQLITE_MASTER.
*/
if( db->init.busy && iDb!=1 ){
sqlite3DbFree(db, pTableName->a[0].zDatabase);
pTableName->a[0].zDatabase = 0;
}
/* If the trigger name was unqualified, and the table is a temp table,
** then set iDb to 1 to create the trigger in the temporary database.
** If sqlite3SrcListLookup() returns 0, indicating the table does not
** exist, the error is caught by the block below.
*/
pTab = sqlite3SrcListLookup(pParse, pTableName);
if( db->init.busy==0 && pName2->n==0 && pTab
&& pTab->pSchema==db->aDb[1].pSchema ){
iDb = 1;
}
/* Ensure the table name matches database name and that the table exists */
if( db->mallocFailed ) goto trigger_cleanup;
assert( pTableName->nSrc==1 );
sqlite3FixInit(&sFix, pParse, iDb, "trigger", pName);
if( sqlite3FixSrcList(&sFix, pTableName) ){
goto trigger_cleanup;
}
pTab = sqlite3SrcListLookup(pParse, pTableName);
if( !pTab ){
/* The table does not exist. */
if( db->init.iDb==1 ){
/* Ticket #3810.
** Normally, whenever a table is dropped, all associated triggers are
** dropped too. But if a TEMP trigger is created on a non-TEMP table
** and the table is dropped by a different database connection, the
** trigger is not visible to the database connection that does the
** drop so the trigger cannot be dropped. This results in an
** "orphaned trigger" - a trigger whose associated table is missing.
*/
db->init.orphanTrigger = 1;
}
goto trigger_cleanup;
}
if( IsVirtual(pTab) ){
sqlite3ErrorMsg(pParse, "cannot create triggers on virtual tables");
goto trigger_cleanup;
}
/* Check that the trigger name is not reserved and that no trigger of the
** specified name exists */
zName = sqlite3NameFromToken(db, pName);
if( !zName || SQLITE_OK!=sqlite3CheckObjectName(pParse, zName) ){
goto trigger_cleanup;
}
assert( sqlite3SchemaMutexHeld(db, iDb, 0) );
if( sqlite3HashFind(&(db->aDb[iDb].pSchema->trigHash),
zName, sqlite3Strlen30(zName)) ){
if( !noErr ){
sqlite3ErrorMsg(pParse, "trigger %T already exists", pName);
}else{
assert( !db->init.busy );
sqlite3CodeVerifySchema(pParse, iDb);
}
goto trigger_cleanup;
}
/* Do not create a trigger on a system table */
if( sqlite3StrNICmp(pTab->zName, "sqlite_", 7)==0 ){
sqlite3ErrorMsg(pParse, "cannot create trigger on system table");
pParse->nErr++;
goto trigger_cleanup;
}
/* INSTEAD of triggers are only for views and views only support INSTEAD
** of triggers.
*/
if( pTab->pSelect && tr_tm!=TK_INSTEAD ){
sqlite3ErrorMsg(pParse, "cannot create %s trigger on view: %S",
(tr_tm == TK_BEFORE)?"BEFORE":"AFTER", pTableName, 0);
goto trigger_cleanup;
}
if( !pTab->pSelect && tr_tm==TK_INSTEAD ){
sqlite3ErrorMsg(pParse, "cannot create INSTEAD OF"
" trigger on table: %S", pTableName, 0);
goto trigger_cleanup;
}
iTabDb = sqlite3SchemaToIndex(db, pTab->pSchema);
#ifndef SQLITE_OMIT_AUTHORIZATION
{
int code = SQLITE_CREATE_TRIGGER;
const char *zDb = db->aDb[iTabDb].zName;
const char *zDbTrig = isTemp ? db->aDb[1].zName : zDb;
if( iTabDb==1 || isTemp ) code = SQLITE_CREATE_TEMP_TRIGGER;
if( sqlite3AuthCheck(pParse, code, zName, pTab->zName, zDbTrig) ){
goto trigger_cleanup;
}
if( sqlite3AuthCheck(pParse, SQLITE_INSERT, SCHEMA_TABLE(iTabDb),0,zDb)){
goto trigger_cleanup;
}
}
#endif
/* INSTEAD OF triggers can only appear on views and BEFORE triggers
** cannot appear on views. So we might as well translate every
** INSTEAD OF trigger into a BEFORE trigger. It simplifies code
** elsewhere.
*/
if (tr_tm == TK_INSTEAD){
tr_tm = TK_BEFORE;
}
/* Build the Trigger object */
pTrigger = (Trigger*)sqlite3DbMallocZero(db, sizeof(Trigger));
if( pTrigger==0 ) goto trigger_cleanup;
pTrigger->zName = zName;
zName = 0;
pTrigger->table = sqlite3DbStrDup(db, pTableName->a[0].zName);
pTrigger->pSchema = db->aDb[iDb].pSchema;
pTrigger->pTabSchema = pTab->pSchema;
pTrigger->op = (u8)op;
pTrigger->tr_tm = tr_tm==TK_BEFORE ? TRIGGER_BEFORE : TRIGGER_AFTER;
pTrigger->pWhen = sqlite3ExprDup(db, pWhen, EXPRDUP_REDUCE);
pTrigger->pColumns = sqlite3IdListDup(db, pColumns);
assert( pParse->pNewTrigger==0 );
pParse->pNewTrigger = pTrigger;
trigger_cleanup:
sqlite3DbFree(db, zName);
sqlite3SrcListDelete(db, pTableName);
sqlite3IdListDelete(db, pColumns);
sqlite3ExprDelete(db, pWhen);
if( !pParse->pNewTrigger ){
sqlite3DeleteTrigger(db, pTrigger);
}else{
assert( pParse->pNewTrigger==pTrigger );
}
}
/*
** Once the sorter has been populated, this function is called to prepare
** for iterating through its contents in sorted order.
*/
int sqlite3VdbeSorterRewind(sqlite3 *db, VdbeCursor *pCsr, int *pbEof){
VdbeSorter *pSorter = pCsr->pSorter;
int rc; /* Return code */
sqlite3_file *pTemp2 = 0; /* Second temp file to use */
i64 iWrite2 = 0; /* Write offset for pTemp2 */
int nIter; /* Number of iterators used */
int nByte; /* Bytes of space required for aIter/aTree */
int N = 2; /* Power of 2 >= nIter */
assert( pSorter );
/* If no data has been written to disk, then do not do so now. Instead,
** sort the VdbeSorter.pRecord list. The vdbe layer will read data directly
** from the in-memory list. */
if( pSorter->nPMA==0 ){
*pbEof = !pSorter->pRecord;
assert( pSorter->aTree==0 );
return vdbeSorterSort(pCsr);
}
/* Write the current b-tree to a PMA. Close the b-tree cursor. */
rc = vdbeSorterListToPMA(db, pCsr);
if( rc!=SQLITE_OK ) return rc;
/* Allocate space for aIter[] and aTree[]. */
nIter = pSorter->nPMA;
if( nIter>SORTER_MAX_MERGE_COUNT ) nIter = SORTER_MAX_MERGE_COUNT;
assert( nIter>0 );
while( N<nIter ) N += N;
nByte = N * (sizeof(int) + sizeof(VdbeSorterIter));
pSorter->aIter = (VdbeSorterIter *)sqlite3DbMallocZero(db, nByte);
if( !pSorter->aIter ) return SQLITE_NOMEM;
pSorter->aTree = (int *)&pSorter->aIter[N];
pSorter->nTree = N;
do {
int iNew; /* Index of new, merged, PMA */
for(iNew=0;
rc==SQLITE_OK && iNew*SORTER_MAX_MERGE_COUNT<pSorter->nPMA;
iNew++
){
i64 nWrite; /* Number of bytes in new PMA */
/* If there are SORTER_MAX_MERGE_COUNT or less PMAs in file pTemp1,
** initialize an iterator for each of them and break out of the loop.
** These iterators will be incrementally merged as the VDBE layer calls
** sqlite3VdbeSorterNext().
**
** Otherwise, if pTemp1 contains more than SORTER_MAX_MERGE_COUNT PMAs,
** initialize interators for SORTER_MAX_MERGE_COUNT of them. These PMAs
** are merged into a single PMA that is written to file pTemp2.
*/
rc = vdbeSorterInitMerge(db, pCsr, &nWrite);
assert( rc!=SQLITE_OK || pSorter->aIter[ pSorter->aTree[1] ].pFile );
if( rc!=SQLITE_OK || pSorter->nPMA<=SORTER_MAX_MERGE_COUNT ){
break;
}
/* Open the second temp file, if it is not already open. */
if( pTemp2==0 ){
assert( iWrite2==0 );
rc = vdbeSorterOpenTempFile(db, &pTemp2);
}
if( rc==SQLITE_OK ){
rc = vdbeSorterWriteVarint(pTemp2, nWrite, &iWrite2);
}
if( rc==SQLITE_OK ){
int bEof = 0;
while( rc==SQLITE_OK && bEof==0 ){
int nToWrite;
VdbeSorterIter *pIter = &pSorter->aIter[ pSorter->aTree[1] ];
assert( pIter->pFile );
nToWrite = pIter->nKey + sqlite3VarintLen(pIter->nKey);
rc = sqlite3OsWrite(pTemp2, pIter->aAlloc, nToWrite, iWrite2);
iWrite2 += nToWrite;
if( rc==SQLITE_OK ){
rc = sqlite3VdbeSorterNext(db, pCsr, &bEof);
}
}
}
}
if( pSorter->nPMA<=SORTER_MAX_MERGE_COUNT ){
break;
}else{
sqlite3_file *pTmp = pSorter->pTemp1;
pSorter->nPMA = iNew;
pSorter->pTemp1 = pTemp2;
pTemp2 = pTmp;
pSorter->iWriteOff = iWrite2;
pSorter->iReadOff = 0;
iWrite2 = 0;
}
}while( rc==SQLITE_OK );
if( pTemp2 ){
sqlite3OsCloseFree(pTemp2);
}
*pbEof = (pSorter->aIter[pSorter->aTree[1]].pFile==0);
return rc;
}
/*
** Invoke a virtual table constructor (either xCreate or xConnect). The
** pointer to the function to invoke is passed as the fourth parameter
** to this procedure.
*/
static int vtabCallConstructor(
sqlite3 *db,
Table *pTab,
Module *pMod,
int (*xConstruct)(sqlite3*,void*,int,const char*const*,sqlite3_vtab**,char**),
char **pzErr
){
VtabCtx sCtx;
VTable *pVTable;
int rc;
const char *const*azArg = (const char *const*)pTab->azModuleArg;
int nArg = pTab->nModuleArg;
char *zErr = 0;
char *zModuleName;
int iDb;
VtabCtx *pCtx;
/* Check that the virtual-table is not already being initialized */
for(pCtx=db->pVtabCtx; pCtx; pCtx=pCtx->pPrior){
if( pCtx->pTab==pTab ){
*pzErr = sqlite3MPrintf(db,
"vtable constructor called recursively: %s", pTab->zName
);
return SQLITE_LOCKED;
}
}
zModuleName = sqlite3MPrintf(db, "%s", pTab->zName);
if( !zModuleName ){
return SQLITE_NOMEM_BKPT;
}
pVTable = sqlite3DbMallocZero(db, sizeof(VTable));
if( !pVTable ){
sqlite3DbFree(db, zModuleName);
return SQLITE_NOMEM_BKPT;
}
pVTable->db = db;
pVTable->pMod = pMod;
iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
pTab->azModuleArg[1] = db->aDb[iDb].zDbSName;
/* Invoke the virtual table constructor */
assert( &db->pVtabCtx );
assert( xConstruct );
sCtx.pTab = pTab;
sCtx.pVTable = pVTable;
sCtx.pPrior = db->pVtabCtx;
sCtx.bDeclared = 0;
db->pVtabCtx = &sCtx;
rc = xConstruct(db, pMod->pAux, nArg, azArg, &pVTable->pVtab, &zErr);
db->pVtabCtx = sCtx.pPrior;
if( rc==SQLITE_NOMEM ) sqlite3OomFault(db);
assert( sCtx.pTab==pTab );
if( SQLITE_OK!=rc ){
if( zErr==0 ){
*pzErr = sqlite3MPrintf(db, "vtable constructor failed: %s", zModuleName);
}else {
*pzErr = sqlite3MPrintf(db, "%s", zErr);
sqlite3_free(zErr);
}
sqlite3DbFree(db, pVTable);
}else if( ALWAYS(pVTable->pVtab) ){
/* Justification of ALWAYS(): A correct vtab constructor must allocate
** the sqlite3_vtab object if successful. */
memset(pVTable->pVtab, 0, sizeof(pVTable->pVtab[0]));
pVTable->pVtab->pModule = pMod->pModule;
pVTable->nRef = 1;
if( sCtx.bDeclared==0 ){
const char *zFormat = "vtable constructor did not declare schema: %s";
*pzErr = sqlite3MPrintf(db, zFormat, pTab->zName);
sqlite3VtabUnlock(pVTable);
rc = SQLITE_ERROR;
}else{
int iCol;
u8 oooHidden = 0;
/* If everything went according to plan, link the new VTable structure
** into the linked list headed by pTab->pVTable. Then loop through the
** columns of the table to see if any of them contain the token "hidden".
** If so, set the Column COLFLAG_HIDDEN flag and remove the token from
** the type string. */
pVTable->pNext = pTab->pVTable;
pTab->pVTable = pVTable;
for(iCol=0; iCol<pTab->nCol; iCol++){
char *zType = sqlite3ColumnType(&pTab->aCol[iCol], "");
int nType;
int i = 0;
nType = sqlite3Strlen30(zType);
for(i=0; i<nType; i++){
if( 0==sqlite3StrNICmp("hidden", &zType[i], 6)
&& (i==0 || zType[i-1]==' ')
&& (zType[i+6]=='\0' || zType[i+6]==' ')
){
break;
}
}
if( i<nType ){
int j;
int nDel = 6 + (zType[i+6] ? 1 : 0);
for(j=i; (j+nDel)<=nType; j++){
zType[j] = zType[j+nDel];
}
if( zType[i]=='\0' && i>0 ){
assert(zType[i-1]==' ');
zType[i-1] = '\0';
}
pTab->aCol[iCol].colFlags |= COLFLAG_HIDDEN;
oooHidden = TF_OOOHidden;
}else{
pTab->tabFlags |= oooHidden;
}
}
}
}
sqlite3DbFree(db, zModuleName);
return rc;
}
/*
** Create and populate a new TriggerPrg object with a sub-program
** implementing trigger pTrigger with ON CONFLICT policy orconf.
*/
static TriggerPrg *codeRowTrigger(
Parse *pParse, /* Current parse context */
Trigger *pTrigger, /* Trigger to code */
Table *pTab, /* The table pTrigger is attached to */
int orconf /* ON CONFLICT policy to code trigger program with */
){
Parse *pTop = sqlite3ParseToplevel(pParse);
sqlite3 *db = pParse->db; /* Database handle */
TriggerPrg *pPrg; /* Value to return */
Expr *pWhen = 0; /* Duplicate of trigger WHEN expression */
Vdbe *v; /* Temporary VM */
NameContext sNC; /* Name context for sub-vdbe */
SubProgram *pProgram = 0; /* Sub-vdbe for trigger program */
Parse *pSubParse; /* Parse context for sub-vdbe */
int iEndTrigger = 0; /* Label to jump to if WHEN is false */
assert( pTrigger->zName==0 || pTab==tableOfTrigger(pTrigger) );
assert( pTop->pVdbe );
/* Allocate the TriggerPrg and SubProgram objects. To ensure that they
** are freed if an error occurs, link them into the Parse.pTriggerPrg
** list of the top-level Parse object sooner rather than later. */
pPrg = sqlite3DbMallocZero(db, sizeof(TriggerPrg));
if( !pPrg ) return 0;
pPrg->pNext = pTop->pTriggerPrg;
pTop->pTriggerPrg = pPrg;
pPrg->pProgram = pProgram = sqlite3DbMallocZero(db, sizeof(SubProgram));
if( !pProgram ) return 0;
sqlite3VdbeLinkSubProgram(pTop->pVdbe, pProgram);
pPrg->pTrigger = pTrigger;
pPrg->orconf = orconf;
pPrg->aColmask[0] = 0xffffffff;
pPrg->aColmask[1] = 0xffffffff;
/* Allocate and populate a new Parse context to use for coding the
** trigger sub-program. */
pSubParse = sqlite3StackAllocZero(db, sizeof(Parse));
if( !pSubParse ) return 0;
memset(&sNC, 0, sizeof(sNC));
sNC.pParse = pSubParse;
pSubParse->db = db;
pSubParse->pTriggerTab = pTab;
pSubParse->pToplevel = pTop;
pSubParse->zAuthContext = pTrigger->zName;
pSubParse->eTriggerOp = pTrigger->op;
pSubParse->nQueryLoop = pParse->nQueryLoop;
v = sqlite3GetVdbe(pSubParse);
if( v ){
VdbeComment((v, "Start: %s.%s (%s %s%s%s ON %s)",
pTrigger->zName, onErrorText(orconf),
(pTrigger->tr_tm==TRIGGER_BEFORE ? "BEFORE" : "AFTER"),
(pTrigger->op==TK_UPDATE ? "UPDATE" : ""),
(pTrigger->op==TK_INSERT ? "INSERT" : ""),
(pTrigger->op==TK_DELETE ? "DELETE" : ""),
pTab->zName
));
#ifndef SQLITE_OMIT_TRACE
sqlite3VdbeChangeP4(v, -1,
sqlite3MPrintf(db, "-- TRIGGER %s", pTrigger->zName), P4_DYNAMIC
);
#endif
/* If one was specified, code the WHEN clause. If it evaluates to false
** (or NULL) the sub-vdbe is immediately halted by jumping to the
** OP_Halt inserted at the end of the program. */
if( pTrigger->pWhen ){
pWhen = sqlite3ExprDup(db, pTrigger->pWhen, 0);
if( SQLITE_OK==sqlite3ResolveExprNames(&sNC, pWhen)
&& db->mallocFailed==0
){
iEndTrigger = sqlite3VdbeMakeLabel(v);
sqlite3ExprIfFalse(pSubParse, pWhen, iEndTrigger, SQLITE_JUMPIFNULL);
}
sqlite3ExprDelete(db, pWhen);
}
/* Code the trigger program into the sub-vdbe. */
codeTriggerProgram(pSubParse, pTrigger->step_list, orconf);
/* Insert an OP_Halt at the end of the sub-program. */
if( iEndTrigger ){
sqlite3VdbeResolveLabel(v, iEndTrigger);
}
sqlite3VdbeAddOp0(v, OP_Halt);
VdbeComment((v, "End: %s.%s", pTrigger->zName, onErrorText(orconf)));
transferParseError(pParse, pSubParse);
if( db->mallocFailed==0 ){
pProgram->aOp = sqlite3VdbeTakeOpArray(v, &pProgram->nOp, &pTop->nMaxArg);
}
pProgram->nMem = pSubParse->nMem;
pProgram->nCsr = pSubParse->nTab;
pProgram->nOnce = pSubParse->nOnce;
pProgram->token = (void *)pTrigger;
pPrg->aColmask[0] = pSubParse->oldmask;
pPrg->aColmask[1] = pSubParse->newmask;
sqlite3VdbeDelete(v);
}
assert( !pSubParse->pAinc && !pSubParse->pZombieTab );
assert( !pSubParse->pTriggerPrg && !pSubParse->nMaxArg );
sqlite3StackFree(db, pSubParse);
return pPrg;
}
