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vdbe.c：源码内容

pDb->pSchema->schema_cookie = pIn3->u.i;
db->flags |= SQLITE_InternChanges;
}else if( pOp->p2==1 ){
/* Record changes in the file format */
pDb->pSchema->file_format = pIn3->u.i;
}
if( pOp->p1==1 ){
/* Invalidate all prepared statements whenever the TEMP database
** schema is changed. Ticket #1644 */
sqlite3ExpirePreparedStatements(db);
}
break;
}
/* Opcode: VerifyCookie P1 P2 *
**
** Check the value of global database parameter number 0 (the
** schema version) and make sure it is equal to P2.
** P1 is the database number which is 0 for the main database file
** and 1 for the file holding temporary tables and some higher number
** for auxiliary databases.
**
** The cookie changes its value whenever the database schema changes.
** This operation is used to detect when that the cookie has changed
** and that the current process needs to reread the schema.
**
** Either a transaction needs to have been started or an OP_Open needs
** to be executed (to establish a read lock) before this opcode is
** invoked.
*/
case OP_VerifyCookie: {
int iMeta;
Btree *pBt;
assert( pOp->p1>=0 && pOp->p1<db->nDb );
assert( (p->btreeMask & (1<<pOp->p1))!=0 );
pBt = db->aDb[pOp->p1].pBt;
if( pBt ){
rc = sqlite3BtreeGetMeta(pBt, 1, (u32 *)&iMeta);
}else{
rc = SQLITE_OK;
iMeta = 0;
}
if( rc==SQLITE_OK && iMeta!=pOp->p2 ){
sqlite3_free(p->zErrMsg);
p->zErrMsg = sqlite3DbStrDup(db, "database schema has changed");
/* If the schema-cookie from the database file matches the cookie
** stored with the in-memory representation of the schema, do
** not reload the schema from the database file.
**
** If virtual-tables are in use, this is not just an optimisation.
** Often, v-tables store their data in other SQLite tables, which
** are queried from within xNext() and other v-table methods using
** prepared queries. If such a query is out-of-date, we do not want to
** discard the database schema, as the user code implementing the
** v-table would have to be ready for the sqlite3_vtab structure itself
** to be invalidated whenever sqlite3_step() is called from within
** a v-table method.
*/
if( db->aDb[pOp->p1].pSchema->schema_cookie!=iMeta ){
sqlite3ResetInternalSchema(db, pOp->p1);
}
sqlite3ExpirePreparedStatements(db);
rc = SQLITE_SCHEMA;
}
break;
}
/* Opcode: OpenRead P1 P2 P3 P4 P5
**
** Open a read-only cursor for the database table whose root page is
** P2 in a database file. The database file is determined by P3.
** P3==0 means the main database, P3==1 means the database used for
** temporary tables, and P3>1 means used the corresponding attached
** database. Give the new cursor an identifier of P1. The P1
** values need not be contiguous but all P1 values should be small integers.
** It is an error for P1 to be negative.
**
** If P5!=0 then use the content of register P2 as the root page, not
** the value of P2 itself.
**
** There will be a read lock on the database whenever there is an
** open cursor. If the database was unlocked prior to this instruction
** then a read lock is acquired as part of this instruction. A read
** lock allows other processes to read the database but prohibits
** any other process from modifying the database. The read lock is
** released when all cursors are closed. If this instruction attempts
** to get a read lock but fails, the script terminates with an
** SQLITE_BUSY error code.
**
** The P4 value is a pointer to a KeyInfo structure that defines the
** content and collating sequence of indices. P4 is NULL for cursors
** that are not pointing to indices.
**
** See also OpenWrite.
*/
/* Opcode: OpenWrite P1 P2 P3 P4 P5
**
** Open a read/write cursor named P1 on the table or index whose root
** page is P2. Or if P5!=0 use the content of register P2 to find the
** root page.
**
** The P4 value is a pointer to a KeyInfo structure that defines the
** content and collating sequence of indices. P4 is NULL for cursors
** that are not pointing to indices.
**
** This instruction works just like OpenRead except that it opens the cursor
** in read/write mode. For a given table, there can be one or more read-only
** cursors or a single read/write cursor but not both.
**
** See also OpenRead.
*/
case OP_OpenRead:
case OP_OpenWrite: {
int i = pOp->p1;
int p2 = pOp->p2;
int iDb = pOp->p3;
int wrFlag;
Btree *pX;
Cursor *pCur;
Db *pDb;
assert( iDb>=0 && iDb<db->nDb );
assert( (p->btreeMask & (1<<iDb))!=0 );
pDb = &db->aDb[iDb];
pX = pDb->pBt;
assert( pX!=0 );
if( pOp->opcode==OP_OpenWrite ){
wrFlag = 1;
if( pDb->pSchema->file_format < p->minWriteFileFormat ){
p->minWriteFileFormat = pDb->pSchema->file_format;
}
}else{
wrFlag = 0;
}
if( pOp->p5 ){
assert( p2>0 );
assert( p2<=p->nMem );
pIn2 = &p->aMem[p2];
sqlite3VdbeMemIntegerify(pIn2);
p2 = pIn2->u.i;
assert( p2>=2 );
}
assert( i>=0 );
pCur = allocateCursor(p, i, &pOp[-1], iDb, 1);
if( pCur==0 ) goto no_mem;
pCur->nullRow = 1;
rc = sqlite3BtreeCursor(pX, p2, wrFlag, pOp->p4.p, pCur->pCursor);
if( pOp->p4type==P4_KEYINFO ){
pCur->pKeyInfo = pOp->p4.pKeyInfo;
pCur->pIncrKey = &pCur->pKeyInfo->incrKey;
pCur->pKeyInfo->enc = ENC(p->db);
}else{
pCur->pKeyInfo = 0;
pCur->pIncrKey = &pCur->bogusIncrKey;
}
switch( rc ){
case SQLITE_BUSY: {
p->pc = pc;
p->rc = rc = SQLITE_BUSY;
goto vdbe_return;
}
case SQLITE_OK: {
int flags = sqlite3BtreeFlags(pCur->pCursor);
/* Sanity checking. Only the lower four bits of the flags byte should
** be used. Bit 3 (mask 0x08) is unpreditable. The lower 3 bits
** (mask 0x07) should be either 5 (intkey+leafdata for tables) or
** 2 (zerodata for indices). If these conditions are not met it can
** only mean that we are dealing with a corrupt database file
*/
if( (flags & 0xf0)!=0 || ((flags & 0x07)!=5 && (flags & 0x07)!=2) ){
rc = SQLITE_CORRUPT_BKPT;
goto abort_due_to_error;
}
pCur->isTable = (flags & BTREE_INTKEY)!=0;
pCur->isIndex = (flags & BTREE_ZERODATA)!=0;
/* If P4==0 it means we are expected to open a table. If P4!=0 then
** we expect to be opening an index. If this is not what happened,
** then the database is corrupt
*/
if( (pCur->isTable && pOp->p4type==P4_KEYINFO)
|| (pCur->isIndex && pOp->p4type!=P4_KEYINFO) ){
rc = SQLITE_CORRUPT_BKPT;
goto abort_due_to_error;
}
break;
}
case SQLITE_EMPTY: {
pCur->isTable = pOp->p4type!=P4_KEYINFO;
pCur->isIndex = !pCur->isTable;
pCur->pCursor = 0;
rc = SQLITE_OK;
break;
}
default: {
goto abort_due_to_error;
}
}
break;
}
/* Opcode: OpenEphemeral P1 P2 * P4 *
**
** Open a new cursor P1 to a transient table.
** The cursor is always opened read/write even if
** the main database is read-only. The transient or virtual
** table is deleted automatically when the cursor is closed.
**
** P2 is the number of columns in the virtual table.
** The cursor points to a BTree table if P4==0 and to a BTree index
** if P4 is not 0. If P4 is not NULL, it points to a KeyInfo structure
** that defines the format of keys in the index.
**
** This opcode was once called OpenTemp. But that created
** confusion because the term "temp table", might refer either
** to a TEMP table at the SQL level, or to a table opened by
** this opcode. Then this opcode was call OpenVirtual. But
** that created confusion with the whole virtual-table idea.
*/
case OP_OpenEphemeral: {
int i = pOp->p1;
Cursor *pCx;
static const int openFlags =
SQLITE_OPEN_READWRITE |
SQLITE_OPEN_CREATE |
SQLITE_OPEN_EXCLUSIVE |
SQLITE_OPEN_DELETEONCLOSE |
SQLITE_OPEN_TRANSIENT_DB;
assert( i>=0 );
pCx = allocateCursor(p, i, pOp, -1, 1);
if( pCx==0 ) goto no_mem;
pCx->nullRow = 1;
rc = sqlite3BtreeFactory(db, 0, 1, SQLITE_DEFAULT_TEMP_CACHE_SIZE, openFlags,
&pCx->pBt);
if( rc==SQLITE_OK ){
rc = sqlite3BtreeBeginTrans(pCx->pBt, 1);
}
if( rc==SQLITE_OK ){
/* If a transient index is required, create it by calling
** sqlite3BtreeCreateTable() with the BTREE_ZERODATA flag before
** opening it. If a transient table is required, just use the
** automatically created table with root-page 1 (an INTKEY table).
*/
if( pOp->p4.pKeyInfo ){
int pgno;
assert( pOp->p4type==P4_KEYINFO );
rc = sqlite3BtreeCreateTable(pCx->pBt, &pgno, BTREE_ZERODATA);
if( rc==SQLITE_OK ){
assert( pgno==MASTER_ROOT+1 );
rc = sqlite3BtreeCursor(pCx->pBt, pgno, 1,
(KeyInfo*)pOp->p4.z, pCx->pCursor);
pCx->pKeyInfo = pOp->p4.pKeyInfo;
pCx->pKeyInfo->enc = ENC(p->db);
pCx->pIncrKey = &pCx->pKeyInfo->incrKey;
}
pCx->isTable = 0;
}else{
rc = sqlite3BtreeCursor(pCx->pBt, MASTER_ROOT, 1, 0, pCx->pCursor);
pCx->isTable = 1;
pCx->pIncrKey = &pCx->bogusIncrKey;
}
}
pCx->isIndex = !pCx->isTable;
break;
}
/* Opcode: OpenPseudo P1 P2 * * *
**
** Open a new cursor that points to a fake table that contains a single
** row of data. Any attempt to write a second row of data causes the
** first row to be deleted. All data is deleted when the cursor is
** closed.
**
** A pseudo-table created by this opcode is useful for holding the
** NEW or OLD tables in a trigger. Also used to hold the a single
** row output from the sorter so that the row can be decomposed into
** individual columns using the OP_Column opcode.
**
** When OP_Insert is executed to insert a row in to the pseudo table,
** the pseudo-table cursor may or may not make it's own copy of the
** original row data. If P2 is 0, then the pseudo-table will copy the
** original row data. Otherwise, a pointer to the original memory cell
** is stored. In this case, the vdbe program must ensure that the
** memory cell containing the row data is not overwritten until the
** pseudo table is closed (or a new row is inserted into it).
*/
case OP_OpenPseudo: {
int i = pOp->p1;
Cursor *pCx;
assert( i>=0 );
pCx = allocateCursor(p, i, &pOp[-1], -1, 0);
if( pCx==0 ) goto no_mem;
pCx->nullRow = 1;
pCx->pseudoTable = 1;
pCx->ephemPseudoTable = pOp->p2;
pCx->pIncrKey = &pCx->bogusIncrKey;
pCx->isTable = 1;
pCx->isIndex = 0;
break;
}
/* Opcode: Close P1 * * * *
**
** Close a cursor previously opened as P1. If P1 is not
** currently open, this instruction is a no-op.
*/
case OP_Close: {
int i = pOp->p1;
assert( i>=0 && i<p->nCursor );
sqlite3VdbeFreeCursor(p, p->apCsr[i]);
p->apCsr[i] = 0;
break;
}
/* Opcode: MoveGe P1 P2 P3 * *
**
** Use the value in register P3 as a key. Reposition
** cursor P1 so that it points to the smallest entry that is greater
** than or equal to the key in register P3.
** If there are no records greater than or equal to the key and P2
** is not zero, then jump to P2.
**
** A special feature of this opcode (and different from the
** related OP_MoveGt, OP_MoveLt, and OP_MoveLe) is that if P2 is
** zero and P1 is an SQL table (a b-tree with integer keys) then
** the seek is deferred until it is actually needed. It might be
** the case that the cursor is never accessed. By deferring the
** seek, we avoid unnecessary seeks.
**
** See also: Found, NotFound, Distinct, MoveLt, MoveGt, MoveLe
*/
/* Opcode: MoveGt P1 P2 P3 * *
**
** Use the value in register P3 as a key. Reposition
** cursor P1 so that it points to the smallest entry that is greater
** than the key in register P3.
** If there are no records greater than the key
** then jump to P2.
**
** See also: Found, NotFound, Distinct, MoveLt, MoveGe, MoveLe
*/
/* Opcode: MoveLt P1 P2 P3 * *
**
** Use the value in register P3 as a key. Reposition
** cursor P1 so that it points to the largest entry that is less
** than the key in register P3.
** If there are no records less than the key
** then jump to P2.
**
** See also: Found, NotFound, Distinct, MoveGt, MoveGe, MoveLe
*/
/* Opcode: MoveLe P1 P2 P3 * *
**
** Use the value in register P3 as a key. Reposition
** cursor P1 so that it points to the largest entry that is less than
** or equal to the key.
** If there are no records less than or eqal to the key
** then jump to P2.
**
** See also: Found, NotFound, Distinct, MoveGt, MoveGe, MoveLt
*/
case OP_MoveLt: /* jump, in3 */
case OP_MoveLe: /* jump, in3 */
case OP_MoveGe: /* jump, in3 */
case OP_MoveGt: { /* jump, in3 */
int i = pOp->p1;
Cursor *pC;
assert( i>=0 && i<p->nCursor );
pC = p->apCsr[i];
assert( pC!=0 );
if( pC->pCursor!=0 ){
int res, oc;
oc = pOp->opcode;
pC->nullRow = 0;
*pC->pIncrKey = oc==OP_MoveGt || oc==OP_MoveLe;
if( pC->isTable ){
i64 iKey = sqlite3VdbeIntValue(pIn3);
if( pOp->p2==0 ){
assert( pOp->opcode==OP_MoveGe );
pC->movetoTarget = iKey;
pC->rowidIsValid = 0;
pC->deferredMoveto = 1;
break;
}
rc = sqlite3BtreeMoveto(pC->pCursor, 0, 0, (u64)iKey, 0, &res);
if( rc!=SQLITE_OK ){
goto abort_due_to_error;
}
pC->lastRowid = iKey;
pC->rowidIsValid = res==0;
}else{
assert( pIn3->flags & MEM_Blob );
ExpandBlob(pIn3);
rc = sqlite3BtreeMoveto(pC->pCursor, pIn3->z, 0, pIn3->n, 0, &res);
if( rc!=SQLITE_OK ){
goto abort_due_to_error;
}
pC->rowidIsValid = 0;
}
pC->deferredMoveto = 0;
pC->cacheStatus = CACHE_STALE;
*pC->pIncrKey = 0;
#ifdef SQLITE_TEST
sqlite3_search_count++;
#endif
if( oc==OP_MoveGe || oc==OP_MoveGt ){
if( res<0 ){
rc = sqlite3BtreeNext(pC->pCursor, &res);
if( rc!=SQLITE_OK ) goto abort_due_to_error;
pC->rowidIsValid = 0;
}else{
res = 0;
}
}else{
assert( oc==OP_MoveLt || oc==OP_MoveLe );
if( res>=0 ){
rc = sqlite3BtreePrevious(pC->pCursor, &res);
if( rc!=SQLITE_OK ) goto abort_due_to_error;
pC->rowidIsValid = 0;
}else{
/* res might be negative because the table is empty. Check to
** see if this is the case.
*/
res = sqlite3BtreeEof(pC->pCursor);
}
}
assert( pOp->p2>0 );
if( res ){
pc = pOp->p2 - 1;
}
}
break;
}
/* Opcode: Found P1 P2 P3 * *
**
** Register P3 holds a blob constructed by MakeRecord. P1 is an index.
** If an entry that matches the value in register p3 exists in P1 then
** jump to P2. If the P3 value does not match any entry in P1
** then fall thru. The P1 cursor is left pointing at the matching entry
** if it exists.
**
** This instruction is used to implement the IN operator where the
** left-hand side is a SELECT statement. P1 may be a true index, or it
** may be a temporary index that holds the results of the SELECT
** statement. This instruction is also used to implement the
** DISTINCT keyword in SELECT statements.
**
** This instruction checks if index P1 contains a record for which
** the first N serialised values exactly match the N serialised values
** in the record in register P3, where N is the total number of values in
** the P3 record (the P3 record is a prefix of the P1 record).
**
** See also: NotFound, MoveTo, IsUnique, NotExists
*/
/* Opcode: NotFound P1 P2 P3 * *
**
** Register P3 holds a blob constructed by MakeRecord. P1 is
** an index. If no entry exists in P1 that matches the blob then jump
** to P2. If an entry does existing, fall through. The cursor is left
** pointing to the entry that matches.
**
** See also: Found, MoveTo, NotExists, IsUnique
*/
case OP_NotFound: /* jump, in3 */
case OP_Found: { /* jump, in3 */
int i = pOp->p1;
int alreadyExists = 0;
Cursor *pC;
assert( i>=0 && i<p->nCursor );
assert( p->apCsr[i]!=0 );
if( (pC = p->apCsr[i])->pCursor!=0 ){
int res;
assert( pC->isTable==0 );
assert( pIn3->flags & MEM_Blob );
if( pOp->opcode==OP_Found ){
pC->pKeyInfo->prefixIsEqual = 1;
}
rc = sqlite3BtreeMoveto(pC->pCursor, pIn3->z, 0, pIn3->n, 0, &res);
pC->pKeyInfo->prefixIsEqual = 0;
if( rc!=SQLITE_OK ){
break;
}
alreadyExists = (res==0);
pC->deferredMoveto = 0;
pC->cacheStatus = CACHE_STALE;
}
if( pOp->opcode==OP_Found ){
if( alreadyExists ) pc = pOp->p2 - 1;
}else{
if( !alreadyExists ) pc = pOp->p2 - 1;
}
break;
}
/* Opcode: IsUnique P1 P2 P3 P4 *
**
** The P3 register contains an integer record number. Call this
** record number R. The P4 register contains an index key created
** using MakeIdxRec. Call it K.
**
** P1 is an index. So it has no data and its key consists of a
** record generated by OP_MakeRecord where the last field is the
** rowid of the entry that the index refers to.
**
** This instruction asks if there is an entry in P1 where the
** fields matches K but the rowid is different from R.
** If there is no such entry, then there is an immediate
** jump to P2. If any entry does exist where the index string
** matches K but the record number is not R, then the record
** number for that entry is written into P3 and control
** falls through to the next instruction.
**
** See also: NotFound, NotExists, Found
*/
case OP_IsUnique: { /* jump, in3 */
int i = pOp->p1;
Cursor *pCx;
BtCursor *pCrsr;
Mem *pK;
i64 R;
/* Pop the value R off the top of the stack
*/
assert( pOp->p4type==P4_INT32 );
assert( pOp->p4.i>0 && pOp->p4.i<=p->nMem );
pK = &p->aMem[pOp->p4.i];
sqlite3VdbeMemIntegerify(pIn3);
R = pIn3->u.i;
assert( i>=0 && i<p->nCursor );
pCx = p->apCsr[i];
assert( pCx!=0 );
pCrsr = pCx->pCursor;
if( pCrsr!=0 ){
int res;
i64 v; /* The record number on the P1 entry that matches K */
char *zKey; /* The value of K */
int nKey; /* Number of bytes in K */
int len; /* Number of bytes in K without the rowid at the end */
int szRowid; /* Size of the rowid column at the end of zKey */
/* Make sure K is a string and make zKey point to K
*/
assert( pK->flags & MEM_Blob );
zKey = pK->z;
nKey = pK->n;
szRowid = sqlite3VdbeIdxRowidLen((u8*)zKey);
len = nKey-szRowid;
/* Search for an entry in P1 where all but the last four bytes match K.
** If there is no such entry, jump immediately to P2.
*/
assert( pCx->deferredMoveto==0 );
pCx->cacheStatus = CACHE_STALE;
rc = sqlite3BtreeMoveto(pCrsr, zKey, 0, len, 0, &res);
if( rc!=SQLITE_OK ){
goto abort_due_to_error;
}
if( res<0 ){
rc = sqlite3BtreeNext(pCrsr, &res);
if( res ){
pc = pOp->p2 - 1;
break;
}
}
rc = sqlite3VdbeIdxKeyCompare(pCx, len, (u8*)zKey, &res);
if( rc!=SQLITE_OK ) goto abort_due_to_error;
if( res>0 ){
pc = pOp->p2 - 1;
break;
}
/* At this point, pCrsr is pointing to an entry in P1 where all but
** the final entry (the rowid) matches K. Check to see if the
** final rowid column is different from R. If it equals R then jump
** immediately to P2.
*/
rc = sqlite3VdbeIdxRowid(pCrsr, &v);
if( rc!=SQLITE_OK ){
goto abort_due_to_error;
}
if( v==R ){
pc = pOp->p2 - 1;
break;
}
/* The final varint of the key is different from R. Store it back
** into register R3. (The record number of an entry that violates
** a UNIQUE constraint.)
*/
pIn3->u.i = v;
assert( pIn3->flags&MEM_Int );
}
break;
}
/* Opcode: NotExists P1 P2 P3 * *
**
** Use the content of register P3 as a integer key. If a record
** with that key does not exist in table of P1, then jump to P2.
** If the record does exist, then fall thru. The cursor is left
** pointing to the record if it exists.
**
** The difference between this operation and NotFound is that this
** operation assumes the key is an integer and that P1 is a table whereas
** NotFound assumes key is a blob constructed from MakeRecord and
** P1 is an index.
**
** See also: Found, MoveTo, NotFound, IsUnique
*/
case OP_NotExists: { /* jump, in3 */
int i = pOp->p1;
Cursor *pC;
BtCursor *pCrsr;
assert( i>=0 && i<p->nCursor );
assert( p->apCsr[i]!=0 );
if( (pCrsr = (pC = p->apCsr[i])->pCursor)!=0 ){
int res;
u64 iKey;
assert( pIn3->flags & MEM_Int );
assert( p->apCsr[i]->isTable );
iKey = intToKey(pIn3->u.i);
rc = sqlite3BtreeMoveto(pCrsr, 0, 0, iKey, 0,&res);
pC->lastRowid = pIn3->u.i;
pC->rowidIsValid = res==0;
pC->nullRow = 0;
pC->cacheStatus = CACHE_STALE;
/* res might be uninitialized if rc!=SQLITE_OK. But if rc!=SQLITE_OK
** processing is about to abort so we really do not care whether or not
** the following jump is taken. (In other words, do not stress over
** the error that valgrind sometimes shows on the next statement when
** running ioerr.test and similar failure-recovery test scripts.) */
if( res!=0 ){
pc = pOp->p2 - 1;
assert( pC->rowidIsValid==0 );
}
}
break;
}
/* Opcode: Sequence P1 P2 * * *
**
** Find the next available sequence number for cursor P1.
** Write the sequence number into register P2.
** The sequence number on the cursor is incremented after this
** instruction.
*/
case OP_Sequence: { /* out2-prerelease */
int i = pOp->p1;
assert( i>=0 && i<p->nCursor );
assert( p->apCsr[i]!=0 );
pOut->u.i = p->apCsr[i]->seqCount++;
MemSetTypeFlag(pOut, MEM_Int);
break;
}
/* Opcode: NewRowid P1 P2 P3 * *
**
** Get a new integer record number (a.k.a "rowid") used as the key to a table.
** The record number is not previously used as a key in the database
** table that cursor P1 points to. The new record number is written
** written to register P2.
**
** If P3>0 then P3 is a register that holds the largest previously
** generated record number. No new record numbers are allowed to be less
** than this value. When this value reaches its maximum, a SQLITE_FULL
** error is generated. The P3 register is updated with the generated
** record number. This P3 mechanism is used to help implement the
** AUTOINCREMENT feature.
*/
case OP_NewRowid: { /* out2-prerelease */
int i = pOp->p1;
i64 v = 0;
Cursor *pC;
assert( i>=0 && i<p->nCursor );
assert( p->apCsr[i]!=0 );
if( (pC = p->apCsr[i])->pCursor==0 ){
/* The zero initialization above is all that is needed */
}else{
/* The next rowid or record number (different terms for the same
** thing) is obtained in a two-step algorithm.
**
** First we attempt to find the largest existing rowid and add one
** to that. But if the largest existing rowid is already the maximum
** positive integer, we have to fall through to the second
** probabilistic algorithm
**
** The second algorithm is to select a rowid at random and see if
** it already exists in the table. If it does not exist, we have
** succeeded. If the random rowid does exist, we select a new one
** and try again, up to 1000 times.
**
** For a table with less than 2 billion entries, the probability
** of not finding a unused rowid is about 1.0e-300. This is a
** non-zero probability, but it is still vanishingly small and should
** never cause a problem. You are much, much more likely to have a
** hardware failure than for this algorithm to fail.
**
** The analysis in the previous paragraph assumes that you have a good
** source of random numbers. Is a library function like lrand48()
** good enough? Maybe. Maybe not. It's hard to know whether there
** might be subtle bugs is some implementations of lrand48() that
** could cause problems. To avoid uncertainty, SQLite uses its own
** random number generator based on the RC4 algorithm.
**
** To promote locality of reference for repetitive inserts, the
** first few attempts at chosing a random rowid pick values just a little
** larger than the previous rowid. This has been shown experimentally
** to double the speed of the COPY operation.
*/
int res, rx=SQLITE_OK, cnt;
i64 x;
cnt = 0;
if( (sqlite3BtreeFlags(pC->pCursor)&(BTREE_INTKEY|BTREE_ZERODATA)) !=
BTREE_INTKEY ){
rc = SQLITE_CORRUPT_BKPT;
goto abort_due_to_error;
}
assert( (sqlite3BtreeFlags(pC->pCursor) & BTREE_INTKEY)!=0 );
assert( (sqlite3BtreeFlags(pC->pCursor) & BTREE_ZERODATA)==0 );
#ifdef SQLITE_32BIT_ROWID
# define MAX_ROWID 0x7fffffff
#else
/* Some compilers complain about constants of the form 0x7fffffffffffffff.
** Others complain about 0x7ffffffffffffffffLL. The following macro seems
** to provide the constant while making all compilers happy.
*/
# define MAX_ROWID ( (((u64)0x7fffffff)<<32) | (u64)0xffffffff )
#endif
if( !pC->useRandomRowid ){
if( pC->nextRowidValid ){
v = pC->nextRowid;
}else{
rc = sqlite3BtreeLast(pC->pCursor, &res);
if( rc!=SQLITE_OK ){
goto abort_due_to_error;
}
if( res ){
v = 1;
}else{
sqlite3BtreeKeySize(pC->pCursor, &v);
v = keyToInt(v);
if( v==MAX_ROWID ){
pC->useRandomRowid = 1;
}else{
v++;
}
}
}
#ifndef SQLITE_OMIT_AUTOINCREMENT
if( pOp->p3 ){
Mem *pMem;
assert( pOp->p3>0 && pOp->p3<=p->nMem ); /* P3 is a valid memory cell */
pMem = &p->aMem[pOp->p3];
REGISTER_TRACE(pOp->p3, pMem);
sqlite3VdbeMemIntegerify(pMem);
assert( (pMem->flags & MEM_Int)!=0 ); /* mem(P3) holds an integer */
if( pMem->u.i==MAX_ROWID || pC->useRandomRowid ){
rc = SQLITE_FULL;
goto abort_due_to_error;
}
if( v<pMem->u.i+1 ){
v = pMem->u.i + 1;
}
pMem->u.i = v;
}
#endif
if( v<MAX_ROWID ){
pC->nextRowidValid = 1;
pC->nextRowid = v+1;
}else{
pC->nextRowidValid = 0;
}
}
if( pC->useRandomRowid ){
assert( pOp->p3==0 ); /* SQLITE_FULL must have occurred prior to this */
v = db->priorNewRowid;
cnt = 0;
do{
if( cnt==0 && (v&0xffffff)==v ){
v++;
}else{
sqlite3_randomness(sizeof(v), &v);
if( cnt<5 ) v &= 0xffffff;
}
if( v==0 ) continue;
x = intToKey(v);
rx = sqlite3BtreeMoveto(pC->pCursor, 0, 0, (u64)x, 0, &res);
cnt++;
}while( cnt<100 && rx==SQLITE_OK && res==0 );
db->priorNewRowid = v;
if( rx==SQLITE_OK && res==0 ){
rc = SQLITE_FULL;
goto abort_due_to_error;
}
}
pC->rowidIsValid = 0;
pC->deferredMoveto = 0;
pC->cacheStatus = CACHE_STALE;
}
MemSetTypeFlag(pOut, MEM_Int);
pOut->u.i = v;
break;
}
/* Opcode: Insert P1 P2 P3 P4 P5
**
** Write an entry into the table of cursor P1. A new entry is
** created if it doesn't already exist or the data for an existing
** entry is overwritten. The data is the value stored register
** number P2. The key is stored in register P3. The key must
** be an integer.
**
** If the OPFLAG_NCHANGE flag of P5 is set, then the row change count is
** incremented (otherwise not). If the OPFLAG_LASTROWID flag of P5 is set,
** then rowid is stored for subsequent return by the
** sqlite3_last_insert_rowid() function (otherwise it is unmodified).
**
** Parameter P4 may point to a string containing the table-name, or
** may be NULL. If it is not NULL, then the update-hook
** (sqlite3.xUpdateCallback) is invoked following a successful insert.
**
** (WARNING/TODO: If P1 is a pseudo-cursor and P2 is dynamically
** allocated, then ownership of P2 is transferred to the pseudo-cursor
** and register P2 becomes ephemeral. If the cursor is changed, the
** value of register P2 will then change. Make sure this does not
** cause any problems.)
**
** This instruction only works on tables. The equivalent instruction
** for indices is OP_IdxInsert.
*/
case OP_Insert: {
Mem *pData = &p->aMem[pOp->p2];
Mem *pKey = &p->aMem[pOp->p3];
i64 iKey; /* The integer ROWID or key for the record to be inserted */
int i = pOp->p1;
Cursor *pC;
assert( i>=0 && i<p->nCursor );
pC = p->apCsr[i];
assert( pC!=0 );
assert( pC->pCursor!=0 || pC->pseudoTable );
assert( pKey->flags & MEM_Int );
assert( pC->isTable );
REGISTER_TRACE(pOp->p2, pData);
REGISTER_TRACE(pOp->p3, pKey);
iKey = intToKey(pKey->u.i);
if( pOp->p5 & OPFLAG_NCHANGE ) p->nChange++;
if( pOp->p5 & OPFLAG_LASTROWID ) db->lastRowid = pKey->u.i;
if( pC->nextRowidValid && pKey->u.i>=pC->nextRowid ){
pC->nextRowidValid = 0;
}
if( pData->flags & MEM_Null ){
pData->z = 0;
pData->n = 0;
}else{
assert( pData->flags & (MEM_Blob|MEM_Str) );
}
if( pC->pseudoTable ){
if( !pC->ephemPseudoTable ){
sqlite3_free(pC->pData);
}
pC->iKey = iKey;
pC->nData = pData->n;
if( pData->z==pData->zMalloc || pC->ephemPseudoTable ){
pC->pData = pData->z;
if( !pC->ephemPseudoTable ){
pData->flags &= ~MEM_Dyn;
pData->flags |= MEM_Ephem;
pData->zMalloc = 0;
}
}else{
pC->pData = sqlite3_malloc( pC->nData+2 );
if( !pC->pData ) goto no_mem;
memcpy(pC->pData, pData->z, pC->nData);
pC->pData[pC->nData] = 0;
pC->pData[pC->nData+1] = 0;
}
pC->nullRow = 0;
}else{
int nZero;
if( pData->flags & MEM_Zero ){
nZero = pData->u.i;
}else{
nZero = 0;
}
rc = sqlite3BtreeInsert(pC->pCursor, 0, iKey,
pData->z, pData->n, nZero,
pOp->p5 & OPFLAG_APPEND);
}
pC->rowidIsValid = 0;
pC->deferredMoveto = 0;
pC->cacheStatus = CACHE_STALE;
/* Invoke the update-hook if required. */
if( rc==SQLITE_OK && db->xUpdateCallback && pOp->p4.z ){
const char *zDb = db->aDb[pC->iDb].zName;
const char *zTbl = pOp->p4.z;
int op = ((pOp->p5 & OPFLAG_ISUPDATE) ? SQLITE_UPDATE : SQLITE_INSERT);
assert( pC->isTable );
db->xUpdateCallback(db->pUpdateArg, op, zDb, zTbl, iKey);
assert( pC->iDb>=0 );
}
break;
}
/* Opcode: Delete P1 P2 * P4 *
**
** Delete the record at which the P1 cursor is currently pointing.
**
** The cursor will be left pointing at either the next or the previous
** record in the table. If it is left pointing at the next record, then
** the next Next instruction will be a no-op. Hence it is OK to delete
** a record from within an Next loop.
**
** If the OPFLAG_NCHANGE flag of P2 is set, then the row change count is
** incremented (otherwise not).
**
** P1 must not be pseudo-table. It has to be a real table with
** multiple rows.
**
** If P4 is not NULL, then it is the name of the table that P1 is
** pointing to. The update hook will be invoked, if it exists.
** If P4 is not NULL then the P1 cursor must have been positioned
** using OP_NotFound prior to invoking this opcode.
*/
case OP_Delete: {
int i = pOp->p1;
i64 iKey;
Cursor *pC;
assert( i>=0 && i<p->nCursor );
pC = p->apCsr[i];
assert( pC!=0 );
assert( pC->pCursor!=0 ); /* Only valid for real tables, no pseudotables */
/* If the update-hook will be invoked, set iKey to the rowid of the
** row being deleted.
*/
if( db->xUpdateCallback && pOp->p4.z ){
assert( pC->isTable );
assert( pC->rowidIsValid ); /* lastRowid set by previous OP_NotFound */
iKey = pC->lastRowid;
}
rc = sqlite3VdbeCursorMoveto(pC);
if( rc ) goto abort_due_to_error;
rc = sqlite3BtreeDelete(pC->pCursor);
pC->nextRowidValid = 0;
pC->cacheStatus = CACHE_STALE;
/* Invoke the update-hook if required. */
if( rc==SQLITE_OK && db->xUpdateCallback && pOp->p4.z ){
const char *zDb = db->aDb[pC->iDb].zName;
const char *zTbl = pOp->p4.z;
db->xUpdateCallback(db->pUpdateArg, SQLITE_DELETE, zDb, zTbl, iKey);
assert( pC->iDb>=0 );
}
if( pOp->p2 & OPFLAG_NCHANGE ) p->nChange++;
break;
}
/* Opcode: ResetCount P1 * *
**
** This opcode resets the VMs internal change counter to 0. If P1 is true,
** then the value of the change counter is copied to the database handle
** change counter (returned by subsequent calls to sqlite3_changes())
** before it is reset. This is used by trigger programs.
*/
case OP_ResetCount: {
if( pOp->p1 ){
sqlite3VdbeSetChanges(db, p->nChange);
}
p->nChange = 0;
break;
}
/* Opcode: RowData P1 P2 * * *
**
** Write into register P2 the complete row data for cursor P1.
** There is no interpretation of the data.
** It is just copied onto the P2 register exactly as
** it is found in the database file.
**
** If the P1 cursor must be pointing to a valid row (not a NULL row)
** of a real table, not a pseudo-table.
*/
/* Opcode: RowKey P1 P2 * * *
**
** Write into register P2 the complete row key for cursor P1.
** There is no interpretation of the data.
** The key is copied onto the P3 register exactly as
** it is found in the database file.
**
** If the P1 cursor must be pointing to a valid row (not a NULL row)
** of a real table, not a pseudo-table.
*/
case OP_RowKey:
case OP_RowData: {
int i = pOp->p1;
Cursor *pC;
BtCursor *pCrsr;
u32 n;
pOut = &p->aMem[pOp->p2];
/* Note that RowKey and RowData are really exactly the same instruction */
assert( i>=0 && i<p->nCursor );
pC = p->apCsr[i];
assert( pC->isTable || pOp->opcode==OP_RowKey );
assert( pC->isIndex || pOp->opcode==OP_RowData );
assert( pC!=0 );
assert( pC->nullRow==0 );
assert( pC->pseudoTable==0 );
assert( pC->pCursor!=0 );
pCrsr = pC->pCursor;
rc = sqlite3VdbeCursorMoveto(pC);
if( rc ) goto abort_due_to_error;
if( pC->isIndex ){
i64 n64;
assert( !pC->isTable );
sqlite3BtreeKeySize(pCrsr, &n64);
if( n64>db->aLimit[SQLITE_LIMIT_LENGTH] ){
goto too_big;
}
n = n64;
}else{
sqlite3BtreeDataSize(pCrsr, &n);
if( n>db->aLimit[SQLITE_LIMIT_LENGTH] ){
goto too_big;
}
}
if( sqlite3VdbeMemGrow(pOut, n, 0) ){
goto no_mem;
}
pOut->n = n;
MemSetTypeFlag(pOut, MEM_Blob);
if( pC->isIndex ){
rc = sqlite3BtreeKey(pCrsr, 0, n, pOut->z);
}else{
rc = sqlite3BtreeData(pCrsr, 0, n, pOut->z);
}
pOut->enc = SQLITE_UTF8; /* In case the blob is ever cast to text */
UPDATE_MAX_BLOBSIZE(pOut);
break;
}
/* Opcode: Rowid P1 P2 * * *
**
** Store in register P2 an integer which is the key of the table entry that
** P1 is currently point to. If p2==0 then push the integer.
*/
case OP_Rowid: { /* out2-prerelease */
int i = pOp->p1;
Cursor *pC;
i64 v;
assert( i>=0 && i<p->nCursor );
pC = p->apCsr[i];
assert( pC!=0 );
rc = sqlite3VdbeCursorMoveto(pC);
if( rc ) goto abort_due_to_error;
if( pC->rowidIsValid ){
v = pC->lastRowid;
}else if( pC->pseudoTable ){
v = keyToInt(pC->iKey);
}else if( pC->nullRow ){
/* Leave the rowid set to a NULL */
break;
}else{
assert( pC->pCursor!=0 );
sqlite3BtreeKeySize(pC->pCursor, &v);
v = keyToInt(v);
}
pOut->u.i = v;
MemSetTypeFlag(pOut, MEM_Int);
break;
}
/* Opcode: NullRow P1 * * * *
**
** Move the cursor P1 to a null row. Any OP_Column operations
** that occur while the cursor is on the null row will always
** write a NULL.
*/
case OP_NullRow: {
int i = pOp->p1;
Cursor *pC;
assert( i>=0 && i<p->nCursor );
pC = p->apCsr[i];
assert( pC!=0 );
pC->nullRow = 1;
pC->rowidIsValid = 0;
break;
}
/* Opcode: Last P1 P2 * * *
**
** The next use of the Rowid or Column or Next instruction for P1
** will refer to the last entry in the database table or index.
** If the table or index is empty and P2>0, then jump immediately to P2.
** If P2 is 0 or if the table or index is not empty, fall through
** to the following instruction.
*/
case OP_Last: { /* jump */
int i = pOp->p1;
Cursor *pC;
BtCursor *pCrsr;
int res;
assert( i>=0 && i<p->nCursor );
pC = p->apCsr[i];
assert( pC!=0 );
pCrsr = pC->pCursor;
assert( pCrsr!=0 );
rc = sqlite3BtreeLast(pCrsr, &res);
pC->nullRow = res;
pC->deferredMoveto = 0;
pC->cacheStatus = CACHE_STALE;
if( res && pOp->p2>0 ){
pc = pOp->p2 - 1;
}
break;
}
/* Opcode: Sort P1 P2 * * *
**
** This opcode does exactly the same thing as OP_Rewind except that
** it increments an undocumented global variable used for testing.
**
** Sorting is accomplished by writing records into a sorting index,
** then rewinding that index and playing it back from beginning to
** end. We use the OP_Sort opcode instead of OP_Rewind to do the
** rewinding so that the global variable will be incremented and
** regression tests can determine whether or not the optimizer is
** correctly optimizing out sorts.
*/
case OP_Sort: { /* jump */
#ifdef SQLITE_TEST
sqlite3_sort_count++;
sqlite3_search_count--;
#endif
/* Fall through into OP_Rewind */
}
/* Opcode: Rewind P1 P2 * * *
**
** The next use of the Rowid or Column or Next instruction for P1
** will refer to the first entry in the database table or index.
** If the table or index is empty and P2>0, then jump immediately to P2.
** If P2 is 0 or if the table or index is not empty, fall through
** to the following instruction.
*/
case OP_Rewind: { /* jump */
int i = pOp->p1;
Cursor *pC;
BtCursor *pCrsr;
int res;
assert( i>=0 && i<p->nCursor );
pC = p->apCsr[i];
assert( pC!=0 );
if( (pCrsr = pC->pCursor)!=0 ){
rc = sqlite3BtreeFirst(pCrsr, &res);
pC->atFirst = res==0;
pC->deferredMoveto = 0;
pC->cacheStatus = CACHE_STALE;
}else{
res = 1;
}
pC->nullRow = res;
assert( pOp->p2>0 && pOp->p2<p->nOp );
if( res ){
pc = pOp->p2 - 1;
}
break;
}
/* Opcode: Next P1 P2 * * *
**
** Advance cursor P1 so that it points to the next key/data pair in its
** table or index. If there are no more key/value pairs then fall through
** to the following instruction. But if the cursor advance was successful,
** jump immediately to P2.
**
** The P1 cursor must be for a real table, not a pseudo-table.
**
** See also: Prev
*/
/* Opcode: Prev P1 P2 * * *
**
** Back up cursor P1 so that it points to the previous key/data pair in its
** table or index. If there is no previous key/value pairs then fall through
** to the following instruction. But if the cursor backup was successful,
** jump immediately to P2.
**
** The P1 cursor must be for a real table, not a pseudo-table.
*/
case OP_Prev: /* jump */
case OP_Next: { /* jump */
Cursor *pC;
BtCursor *pCrsr;
CHECK_FOR_INTERRUPT;
assert( pOp->p1>=0 && pOp->p1<p->nCursor );
pC = p->apCsr[pOp->p1];
if( pC==0 ){
break; /* See ticket #2273 */
}
pCrsr = pC->pCursor;
assert( pCrsr );
if( pC->nullRow==0 ){
int res = 1;
assert( pC->deferredMoveto==0 );
rc = pOp->opcode==OP_Next ? sqlite3BtreeNext(pCrsr, &res) :
sqlite3BtreePrevious(pCrsr, &res);
pC->nullRow = res;
pC->cacheStatus = CACHE_STALE;
if( res==0 ){
pc = pOp->p2 - 1;
#ifdef SQLITE_TEST
sqlite3_search_count++;
#endif
}
}
pC->rowidIsValid = 0;
break;
}
/* Opcode: IdxInsert P1 P2 P3 * *
**
** Register P2 holds a SQL index key made using the
** MakeIdxRec instructions. This opcode writes that key
** into the index P1. Data for the entry is nil.
**
** P3 is a flag that provides a hint to the b-tree layer that this
** insert is likely to be an append.
**
** This instruction only works for indices. The equivalent instruction
** for tables is OP_Insert.
*/
case OP_IdxInsert: { /* in2 */
int i = pOp->p1;
Cursor *pC;
BtCursor *pCrsr;
assert( i>=0 && i<p->nCursor );
assert( p->apCsr[i]!=0 );
assert( pIn2->flags & MEM_Blob );
if( (pCrsr = (pC = p->apCsr[i])->pCursor)!=0 ){
assert( pC->isTable==0 );
rc = ExpandBlob(pIn2);
if( rc==SQLITE_OK ){
int nKey = pIn2->n;
const char *zKey = pIn2->z;
rc = sqlite3BtreeInsert(pCrsr, zKey, nKey, "", 0, 0, pOp->p3);
assert( pC->deferredMoveto==0 );
pC->cacheStatus = CACHE_STALE;
}
}
break;
}
/* Opcode: IdxDeleteM P1 P2 P3 * *
**
** The content of P3 registers starting at register P2 form
** an unpacked index key. This opcode removes that entry from the
** index opened by cursor P1.
*/
case OP_IdxDelete: {
int i = pOp->p1;
Cursor *pC;
BtCursor *pCrsr;
assert( pOp->p3>0 );
assert( pOp->p2>0 && pOp->p2+pOp->p3<=p->nMem );
assert( i>=0 && i<p->nCursor );
assert( p->apCsr[i]!=0 );
if( (pCrsr = (pC = p->apCsr[i])->pCursor)!=0 ){
int res;
UnpackedRecord r;
r.pKeyInfo = pC->pKeyInfo;
r.nField = pOp->p3;
r.needFree = 0;
r.needDestroy = 0;
r.aMem = &p->aMem[pOp->p2];
rc = sqlite3BtreeMoveto(pCrsr, 0, &r, 0, 0, &res);
if( rc==SQLITE_OK && res==0 ){
rc = sqlite3BtreeDelete(pCrsr);
}
assert( pC->deferredMoveto==0 );
pC->cacheStatus = CACHE_STALE;
}
break;
}
/* Opcode: IdxRowid P1 P2 * * *
**
** Write into register P2 an integer which is the last entry in the record at
** the end of the index key pointed to by cursor P1. This integer should be
** the rowid of the table entry to which this index entry points.
**
** See also: Rowid, MakeIdxRec.
*/
case OP_IdxRowid: { /* out2-prerelease */
int i = pOp->p1;
BtCursor *pCrsr;
Cursor *pC;
assert( i>=0 && i<p->nCursor );
assert( p->apCsr[i]!=0 );
if( (pCrsr = (pC = p->apCsr[i])->pCursor)!=0 ){
i64 rowid;
assert( pC->deferredMoveto==0 );
assert( pC->isTable==0 );
if( !pC->nullRow ){
rc = sqlite3VdbeIdxRowid(pCrsr, &rowid);
if( rc!=SQLITE_OK ){
goto abort_due_to_error;
}
MemSetTypeFlag(pOut, MEM_Int);
pOut->u.i = rowid;
}
}
break;
}
/* Opcode: IdxGE P1 P2 P3 * P5
**
** The value in register P3 is an index entry that omits the ROWID. Compare
** this value against the index that P1 is currently pointing to.
** Ignore the ROWID on the P1 index.
**
** If the P1 index entry is greater than or equal to the value in
** register P3 then jump to P2. Otherwise fall through to the next
** instruction.
**
** If P5 is non-zero then the value in register P3 is temporarily
** increased by an epsilon prior to the comparison. This make the opcode work
** like IdxGT except that if the key from register P3 is a prefix of
** the key in the cursor, the result is false whereas it would be
** true with IdxGT.
*/
/* Opcode: IdxLT P1 P2 P3 * P5
**
** The value in register P3 is an index entry that omits the ROWID. Compare
** the this value against the index that P1 is currently pointing to.
** Ignore the ROWID on the P1 index.
**
** If the P1 index entry is less than the register P3 value
** then jump to P2. Otherwise fall through to the next instruction.
**
** If P5 is non-zero then the
** index taken from register P3 is temporarily increased by
** an epsilon prior to the comparison. This makes the opcode work
** like IdxLE.
*/
case OP_IdxLT: /* jump, in3 */
case OP_IdxGE: { /* jump, in3 */
int i= pOp->p1;
Cursor *pC;
assert( i>=0 && i<p->nCursor );
assert( p->apCsr[i]!=0 );
if( (pC = p->apCsr[i])->pCursor!=0 ){
int res;
assert( pIn3->flags & MEM_Blob ); /* Created using OP_MakeRecord */
assert( pC->deferredMoveto==0 );
ExpandBlob(pIn3);
assert( pOp->p5==0 || pOp->p5==1 );
*pC->pIncrKey = pOp->p5;
rc = sqlite3VdbeIdxKeyCompare(pC, pIn3->n, (u8*)pIn3->z, &res);
*pC->pIncrKey = 0;
if( rc!=SQLITE_OK ){
break;
}
if( pOp->opcode==OP_IdxLT ){
res = -res;
}else{
assert( pOp->opcode==OP_IdxGE );
res++;
}
if( res>0 ){
pc = pOp->p2 - 1 ;
}
}
break;
}
/* Opcode: Destroy P1 P2 P3 * *
**
** Delete an entire database table or index whose root page in the database
** file is given by P1.
**
** The table being destroyed is in the main database file if P3==0. If
** P3==1 then the table to be clear is in the auxiliary database file
** that is used to store tables create using CREATE TEMPORARY TABLE.
**
** If AUTOVACUUM is enabled then it is possible that another root page
** might be moved into the newly deleted root page in order to keep all
** root pages contiguous at the beginning of the database. The former
** value of the root page that moved - its value before the move occurred -
** is stored in register P2. If no page
** movement was required (because the table being dropped was already
** the last one in the database) then a zero is stored in register P2.
** If AUTOVACUUM is disabled then a zero is stored in register P2.
**
** See also: Clear
*/
case OP_Destroy: { /* out2-prerelease */
int iMoved;
int iCnt;
#ifndef SQLITE_OMIT_VIRTUALTABLE
Vdbe *pVdbe;
iCnt = 0;
for(pVdbe=db->pVdbe; pVdbe; pVdbe=pVdbe->pNext){
if( pVdbe->magic==VDBE_MAGIC_RUN && pVdbe->inVtabMethod<2 && pVdbe->pc>=0 ){
iCnt++;
}
}
#else
iCnt = db->activeVdbeCnt;
#endif
if( iCnt>1 ){
rc = SQLITE_LOCKED;
p->errorAction = OE_Abort;
}else{
int iDb = pOp->p3;
assert( iCnt==1 );
assert( (p->btreeMask & (1<<iDb))!=0 );
rc = sqlite3BtreeDropTable(db->aDb[iDb].pBt, pOp->p1, &iMoved);
MemSetTypeFlag(pOut, MEM_Int);
pOut->u.i = iMoved;
#ifndef SQLITE_OMIT_AUTOVACUUM
if( rc==SQLITE_OK && iMoved!=0 ){
sqlite3RootPageMoved(&db->aDb[iDb], iMoved, pOp->p1);
}
#endif
}
break;
}
/* Opcode: Clear P1 P2 *
**
** Delete all contents of the database table or index whose root page
** in the database file is given by P1. But, unlike Destroy, do not
** remove the table or index from the database file.
**
** The table being clear is in the main database file if P2==0. If
** P2==1 then the table to be clear is in the auxiliary database file
** that is used to store tables create using CREATE TEMPORARY TABLE.
**
** See also: Destroy
*/
case OP_Clear: {
assert( (p->btreeMask & (1<<pOp->p2))!=0 );
rc = sqlite3BtreeClearTable(db->aDb[pOp->p2].pBt, pOp->p1);
break;
}
/* Opcode: CreateTable P1 P2 * * *
**
** Allocate a new table in the main database file if P1==0 or in the
** auxiliary database file if P1==1 or in an attached database if
** P1>1. Write the root page number of the new table into
** register P2
**
** The difference between a table and an index is this: A table must
** have a 4-byte integer key and can have arbitrary data. An index
** has an arbitrary key but no data.
**
** See also: CreateIndex
*/
/* Opcode: CreateIndex P1 P2 * * *
**
** Allocate a new index in the main database file if P1==0 or in the
** auxiliary database file if P1==1 or in an attached database if
** P1>1. Write the root page number of the new table into
** register P2.
**
** See documentation on OP_CreateTable for additional information.
*/
case OP_CreateIndex: /* out2-prerelease */
case OP_CreateTable: { /* out2-prerelease */
int pgno;
int flags;
Db *pDb;
assert( pOp->p1>=0 && pOp->p1<db->nDb );
assert( (p->btreeMask & (1<<pOp->p1))!=0 );
pDb = &db->aDb[pOp->p1];
assert( pDb->pBt!=0 );
if( pOp->opcode==OP_CreateTable ){
/* flags = BTREE_INTKEY; */
flags = BTREE_LEAFDATA|BTREE_INTKEY;
}else{
flags = BTREE_ZERODATA;
}
rc = sqlite3BtreeCreateTable(pDb->pBt, &pgno, flags);
if( rc==SQLITE_OK ){
pOut->u.i = pgno;
MemSetTypeFlag(pOut, MEM_Int);
}
break;
}
/* Opcode: ParseSchema P1 P2 * P4 *
**
** Read and parse all entries from the SQLITE_MASTER table of database P1
** that match the WHERE clause P4. P2 is the "force" flag. Always do
** the parsing if P2 is true. If P2 is false, then this routine is a
** no-op if the schema is not currently loaded. In other words, if P2
** is false, the SQLITE_MASTER table is only parsed if the rest of the
** schema is already loaded into the symbol table.
**
** This opcode invokes the parser to create a new virtual machine,
** then runs the new virtual machine. It is thus a reentrant opcode.
*/
case OP_ParseSchema: {
char *zSql;
int iDb = pOp->p1;
const char *zMaster;
InitData initData;
assert( iDb>=0 && iDb<db->nDb );
if( !pOp->p2 && !DbHasProperty(db, iDb, DB_SchemaLoaded) ){
break;
}
zMaster = SCHEMA_TABLE(iDb);
initData.db = db;
initData.iDb = pOp->p1;
initData.pzErrMsg = &p->zErrMsg;
zSql = sqlite3MPrintf(db,
"SELECT name, rootpage, sql FROM '%q'.%s WHERE %s",
db->aDb[iDb].zName, zMaster, pOp->p4.z);
if( zSql==0 ) goto no_mem;
(void)sqlite3SafetyOff(db);
assert( db->init.busy==0 );
db->init.busy = 1;
assert( !db->mallocFailed );
rc = sqlite3_exec(db, zSql, sqlite3InitCallback, &initData, 0);
if( rc==SQLITE_ABORT ) rc = initData.rc;
sqlite3_free(zSql);
db->init.busy = 0;
(void)sqlite3SafetyOn(db);
if( rc==SQLITE_NOMEM ){
goto no_mem;
}
break;
}
#if !defined(SQLITE_OMIT_ANALYZE) && !defined(SQLITE_OMIT_PARSER)
/* Opcode: LoadAnalysis P1 * * * *
**
** Read the sqlite_stat1 table for database P1 and load the content
** of that table into the internal index hash table. This will cause
** the analysis to be used when preparing all subsequent queries.
*/
case OP_LoadAnalysis: {
int iDb = pOp->p1;
assert( iDb>=0 && iDb<db->nDb );
rc = sqlite3AnalysisLoad(db, iDb);
break;
}
#endif /* !defined(SQLITE_OMIT_ANALYZE) && !defined(SQLITE_OMIT_PARSER) */
/* Opcode: DropTable P1 * * P4 *
**
** Remove the internal (in-memory) data structures that describe
** the table named P4 in database P1. This is called after a table
** is dropped in order to keep the internal representation of the
** schema consistent with what is on disk.
*/
case OP_DropTable: {
sqlite3UnlinkAndDeleteTable(db, pOp->p1, pOp->p4.z);
break;
}
/* Opcode: DropIndex P1 * * P4 *
**
** Remove the internal (in-memory) data structures that describe
** the index named P4 in database P1. This is called after an index
** is dropped in order to keep the internal representation of the
** schema consistent with what is on disk.
*/
case OP_DropIndex: {
sqlite3UnlinkAndDeleteIndex(db, pOp->p1, pOp->p4.z);
break;
}
/* Opcode: DropTrigger P1 * * P4 *
**
** Remove the internal (in-memory) data structures that describe
** the trigger named P4 in database P1. This is called after a trigger
** is dropped in order to keep the internal representation of the
** schema consistent with what is on disk.
*/
case OP_DropTrigger: {
sqlite3UnlinkAndDeleteTrigger(db, pOp->p1, pOp->p4.z);
break;
}
#ifndef SQLITE_OMIT_INTEGRITY_CHECK
/* Opcode: IntegrityCk P1 P2 P3 * P5
**
** Do an analysis of the currently open database. Store in
** register P1 the text of an error message describing any problems.
** If no problems are found, store a NULL in register P1.
**
** The register P3 contains the maximum number of allowed errors.
** At most reg(P3) errors will be reported.
** In other words, the analysis stops as soon as reg(P1) errors are
** seen. Reg(P1) is updated with the number of errors remaining.
**
** The root page numbers of all tables in the database are integer
** stored in reg(P1), reg(P1+1), reg(P1+2), .... There are P2 tables
** total.
**
** If P5 is not zero, the check is done on the auxiliary database
** file, not the main database file.
**
** This opcode is used to implement the integrity_check pragma.
*/
case OP_IntegrityCk: {
int nRoot; /* Number of tables to check. (Number of root pages.) */
int *aRoot; /* Array of rootpage numbers for tables to be checked */
int j; /* Loop counter */
int nErr; /* Number of errors reported */
char *z; /* Text of the error report */
Mem *pnErr; /* Register keeping track of errors remaining */
nRoot = pOp->p2;
assert( nRoot>0 );
aRoot = sqlite3_malloc( sizeof(int)*(nRoot+1) );
if( aRoot==0 ) goto no_mem;
assert( pOp->p3>0 && pOp->p3<=p->nMem );
pnErr = &p->aMem[pOp->p3];
assert( (pnErr->flags & MEM_Int)!=0 );
assert( (pnErr->flags & (MEM_Str|MEM_Blob))==0 );
pIn1 = &p->aMem[pOp->p1];
for(j=0; j<nRoot; j++){
aRoot[j] = sqlite3VdbeIntValue(&pIn1[j]);
}
aRoot[j] = 0;
assert( pOp->p5<db->nDb );
assert( (p->btreeMask & (1<<pOp->p5))!=0 );
z = sqlite3BtreeIntegrityCheck(db->aDb[pOp->p5].pBt, aRoot, nRoot,
pnErr->u.i, &nErr);
pnErr->u.i -= nErr;
sqlite3VdbeMemSetNull(pIn1);
if( nErr==0 ){
assert( z==0 );
}else{
sqlite3VdbeMemSetStr(pIn1, z, -1, SQLITE_UTF8, sqlite3_free);
}
UPDATE_MAX_BLOBSIZE(pIn1);
sqlite3VdbeChangeEncoding(pIn1, encoding);
sqlite3_free(aRoot);
break;
}
#endif /* SQLITE_OMIT_INTEGRITY_CHECK */
/* Opcode: FifoWrite P1 * * * *
**
** Write the integer from register P1 into the Fifo.
*/
case OP_FifoWrite: { /* in1 */
if( sqlite3VdbeFifoPush(&p->sFifo, sqlite3VdbeIntValue(pIn1))==SQLITE_NOMEM ){
goto no_mem;
}
break;
}
/* Opcode: FifoRead P1 P2 * * *
**
** Attempt to read a single integer from the Fifo. Store that
** integer in register P1.
**
** If the Fifo is empty jump to P2.
*/
case OP_FifoRead: { /* jump */
CHECK_FOR_INTERRUPT;
assert( pOp->p1>0 && pOp->p1<=p->nMem );
pOut = &p->aMem[pOp->p1];
MemSetTypeFlag(pOut, MEM_Int);
if( sqlite3VdbeFifoPop(&p->sFifo, &pOut->u.i)==SQLITE_DONE ){
pc = pOp->p2 - 1;
}
break;
}
#ifndef SQLITE_OMIT_TRIGGER
/* Opcode: ContextPush * * *
**
** Save the current Vdbe context such that it can be restored by a ContextPop
** opcode. The context stores the last insert row id, the last statement change
** count, and the current statement change count.
*/
case OP_ContextPush: {
int i = p->contextStackTop++;
Context *pContext;
assert( i>=0 );
/* FIX ME: This should be allocated as part of the vdbe at compile-time */
if( i>=p->contextStackDepth ){
p->contextStackDepth = i+1;
p->contextStack = sqlite3DbReallocOrFree(db, p->contextStack,
sizeof(Context)*(i+1));
if( p->contextStack==0 ) goto no_mem;
}
pContext = &p->contextStack[i];
pContext->lastRowid = db->lastRowid;
pContext->nChange = p->nChange;
pContext->sFifo = p->sFifo;
sqlite3VdbeFifoInit(&p->sFifo);
break;
}
/* Opcode: ContextPop * * *
**
** Restore the Vdbe context to the state it was in when contextPush was last
** executed. The context stores the last insert row id, the last statement
** change count, and the current statement change count.
*/
case OP_ContextPop: {
Context *pContext = &p->contextStack[--p->contextStackTop];
assert( p->contextStackTop>=0 );
db->lastRowid = pContext->lastRowid;
p->nChange = pContext->nChange;
sqlite3VdbeFifoClear(&p->sFifo);
p->sFifo = pContext->sFifo;
break;
}
#endif /* #ifndef SQLITE_OMIT_TRIGGER */
#ifndef SQLITE_OMIT_AUTOINCREMENT
/* Opcode: MemMax P1 P2 * * *
**
** Set the value of register P1 to the maximum of its current value
** and the value in register P2.
**
** This instruction throws an error if the memory cell is not initially
** an integer.
*/
case OP_MemMax: { /* in1, in2 */
sqlite3VdbeMemIntegerify(pIn1);
sqlite3VdbeMemIntegerify(pIn2);
if( pIn1->u.i<pIn2->u.i){
pIn1->u.i = pIn2->u.i;
}
break;
}
#endif /* SQLITE_OMIT_AUTOINCREMENT */
/* Opcode: IfPos P1 P2 * * *
**
** If the value of register P1 is 1 or greater, jump to P2.
**
** It is illegal to use this instruction on a register that does
** not contain an integer. An assertion fault will result if you try.
*/
case OP_IfPos: { /* jump, in1 */
assert( pIn1->flags&MEM_Int );
if( pIn1->u.i>0 ){
pc = pOp->p2 - 1;
}
break;
}
/* Opcode: IfNeg P1 P2 * * *
**
** If the value of register P1 is less than zero, jump to P2.
**
** It is illegal to use this instruction on a register that does
** not contain an integer. An assertion fault will result if you try.
*/
case OP_IfNeg: { /* jump, in1 */
assert( pIn1->flags&MEM_Int );
if( pIn1->u.i<0 ){
pc = pOp->p2 - 1;
}
break;
}
/* Opcode: IfZero P1 P2 * * *
**
** If the value of register P1 is exactly 0, jump to P2.
**
** It is illegal to use this instruction on a register that does
** not contain an integer. An assertion fault will result if you try.
*/
case OP_IfZero: { /* jump, in1 */
assert( pIn1->flags&MEM_Int );
if( pIn1->u.i==0 ){
pc = pOp->p2 - 1;
}
break;
}
/* Opcode: AggStep * P2 P3 P4 P5
**
** Execute the step function for an aggregate. The
** function has P5 arguments. P4 is a pointer to the FuncDef
** structure that specifies the function. Use register
** P3 as the accumulator.
**
** The P5 arguments are taken from register P2 and its
** successors.
*/
case OP_AggStep: {
int n = pOp->p5;
int i;
Mem *pMem, *pRec;
sqlite3_context ctx;
sqlite3_value **apVal;
assert( n>=0 );
pRec = &p->aMem[pOp->p2];
apVal = p->apArg;
assert( apVal || n==0 );
for(i=0; i<n; i++, pRec++){
apVal[i] = pRec;
storeTypeInfo(pRec, encoding);
}
ctx.pFunc = pOp->p4.pFunc;
assert( pOp->p3>0 && pOp->p3<=p->nMem );
ctx.pMem = pMem = &p->aMem[pOp->p3];
pMem->n++;
ctx.s.flags = MEM_Null;
ctx.s.z = 0;
ctx.s.zMalloc = 0;
ctx.s.xDel = 0;
ctx.s.db = db;
ctx.isError = 0;
ctx.pColl = 0;
if( ctx.pFunc->needCollSeq ){
assert( pOp>p->aOp );
assert( pOp[-1].p4type==P4_COLLSEQ );
assert( pOp[-1].opcode==OP_CollSeq );
ctx.pColl = pOp[-1].p4.pColl;
}
(ctx.pFunc->xStep)(&ctx, n, apVal);
if( ctx.isError ){
sqlite3SetString(&p->zErrMsg, sqlite3_value_text(&ctx.s), (char*)0);
rc = ctx.isError;
}
sqlite3VdbeMemRelease(&ctx.s);
break;
}
/* Opcode: AggFinal P1 P2 * P4 *
**
** Execute the finalizer function for an aggregate. P1 is
** the memory location that is the accumulator for the aggregate.
**
** P2 is the number of arguments that the step function takes and
** P4 is a pointer to the FuncDef for this function. The P2
** argument is not used by this opcode. It is only there to disambiguate
** functions that can take varying numbers of arguments. The
** P4 argument is only needed for the degenerate case where
** the step function was not previously called.
*/
case OP_AggFinal: {
Mem *pMem;
assert( pOp->p1>0 && pOp->p1<=p->nMem );
pMem = &p->aMem[pOp->p1];
assert( (pMem->flags & ~(MEM_Null|MEM_Agg))==0 );
rc = sqlite3VdbeMemFinalize(pMem, pOp->p4.pFunc);
if( rc==SQLITE_ERROR ){
sqlite3SetString(&p->zErrMsg, sqlite3_value_text(pMem), (char*)0);
}
sqlite3VdbeChangeEncoding(pMem, encoding);
UPDATE_MAX_BLOBSIZE(pMem);
if( sqlite3VdbeMemTooBig(pMem) ){
goto too_big;
}
break;
}
#if !defined(SQLITE_OMIT_VACUUM) && !defined(SQLITE_OMIT_ATTACH)
/* Opcode: Vacuum * * * * *
**
** Vacuum the entire database. This opcode will cause other virtual
** machines to be created and run. It may not be called from within
** a transaction.
*/
case OP_Vacuum: {
if( sqlite3SafetyOff(db) ) goto abort_due_to_misuse;
rc = sqlite3RunVacuum(&p->zErrMsg, db);
if( sqlite3SafetyOn(db) ) goto abort_due_to_misuse;
break;
}
#endif
#if !defined(SQLITE_OMIT_AUTOVACUUM)
/* Opcode: IncrVacuum P1 P2 * * *
**
** Perform a single step of the incremental vacuum procedure on
** the P1 database. If the vacuum has finished, jump to instruction
** P2. Otherwise, fall through to the next instruction.
*/
case OP_IncrVacuum: { /* jump */
Btree *pBt;
assert( pOp->p1>=0 && pOp->p1<db->nDb );
assert( (p->btreeMask & (1<<pOp->p1))!=0 );
pBt = db->aDb[pOp->p1].pBt;
rc = sqlite3BtreeIncrVacuum(pBt);
if( rc==SQLITE_DONE ){
pc = pOp->p2 - 1;
rc = SQLITE_OK;
}
break;
}
#endif
/* Opcode: Expire P1 * * * *
**
** Cause precompiled statements to become expired. An expired statement
** fails with an error code of SQLITE_SCHEMA if it is ever executed
** (via sqlite3_step()).
**
** If P1 is 0, then all SQL statements become expired. If P1 is non-zero,
** then only the currently executing statement is affected.
*/
case OP_Expire: {
if( !pOp->p1 ){
sqlite3ExpirePreparedStatements(db);
}else{
p->expired = 1;
}
break;
}
#ifndef SQLITE_OMIT_SHARED_CACHE
/* Opcode: TableLock P1 P2 P3 P4 *
**
** Obtain a lock on a particular table. This instruction is only used when
** the shared-cache feature is enabled.
**
** If P1 is the index of the database in sqlite3.aDb[] of the database
** on which the lock is acquired. A readlock is obtained if P3==0 or
** a write lock if P3==1.
**
** P2 contains the root-page of the table to lock.
**
** P4 contains a pointer to the name of the table being locked. This is only
** used to generate an error message if the lock cannot be obtained.
*/
case OP_TableLock: {
int p1 = pOp->p1;
u8 isWriteLock = pOp->p3;
assert( p1>=0 && p1<db->nDb );
assert( (p->btreeMask & (1<<p1))!=0 );
assert( isWriteLock==0 || isWriteLock==1 );
rc = sqlite3BtreeLockTable(db->aDb[p1].pBt, pOp->p2, isWriteLock);
if( rc==SQLITE_LOCKED ){
const char *z = pOp->p4.z;
sqlite3SetString(&p->zErrMsg, "database table is locked: ", z, (char*)0);
}
break;
}
#endif /* SQLITE_OMIT_SHARED_CACHE */
#ifndef SQLITE_OMIT_VIRTUALTABLE
/* Opcode: VBegin * * * P4 *
**
** P4 a pointer to an sqlite3_vtab structure. Call the xBegin method
** for that table.
*/
case OP_VBegin: {
rc = sqlite3VtabBegin(db, pOp->p4.pVtab);
break;
}
#endif /* SQLITE_OMIT_VIRTUALTABLE */
#ifndef SQLITE_OMIT_VIRTUALTABLE
/* Opcode: VCreate P1 * * P4 *
**
** P4 is the name of a virtual table in database P1. Call the xCreate method
** for that table.
*/
case OP_VCreate: {
rc = sqlite3VtabCallCreate(db, pOp->p1, pOp->p4.z, &p->zErrMsg);
break;
}
#endif /* SQLITE_OMIT_VIRTUALTABLE */
#ifndef SQLITE_OMIT_VIRTUALTABLE
/* Opcode: VDestroy P1 * * P4 *
**
** P4 is the name of a virtual table in database P1. Call the xDestroy method
** of that table.
*/
case OP_VDestroy: {
p->inVtabMethod = 2;
rc = sqlite3VtabCallDestroy(db, pOp->p1, pOp->p4.z);
p->inVtabMethod = 0;
break;
}
#endif /* SQLITE_OMIT_VIRTUALTABLE */
#ifndef SQLITE_OMIT_VIRTUALTABLE
/* Opcode: VOpen P1 * * P4 *
**
** P4 is a pointer to a virtual table object, an sqlite3_vtab structure.
** P1 is a cursor number. This opcode opens a cursor to the virtual
** table and stores that cursor in P1.
*/
case OP_VOpen: {
Cursor *pCur = 0;
sqlite3_vtab_cursor *pVtabCursor = 0;
sqlite3_vtab *pVtab = pOp->p4.pVtab;
sqlite3_module *pModule = (sqlite3_module *)pVtab->pModule;
assert(pVtab && pModule);
if( sqlite3SafetyOff(db) ) goto abort_due_to_misuse;
rc = pModule->xOpen(pVtab, &pVtabCursor);
if( sqlite3SafetyOn(db) ) goto abort_due_to_misuse;
if( SQLITE_OK==rc ){
/* Initialise sqlite3_vtab_cursor base class */
pVtabCursor->pVtab = pVtab;
/* Initialise vdbe cursor object */
pCur = allocateCursor(p, pOp->p1, &pOp[-1], -1, 0);
if( pCur ){
pCur->pVtabCursor = pVtabCursor;
pCur->pModule = pVtabCursor->pVtab->pModule;
}else{
db->mallocFailed = 1;
pModule->xClose(pVtabCursor);
}
}
break;
}
#endif /* SQLITE_OMIT_VIRTUALTABLE */
#ifndef SQLITE_OMIT_VIRTUALTABLE
/* Opcode: VFilter P1 P2 P3 P4 *
**
** P1 is a cursor opened using VOpen. P2 is an address to jump to if
** the filtered result set is empty.
**
** P4 is either NULL or a string that was generated by the xBestIndex
** method of the module. The interpretation of the P4 string is left
** to the module implementation.
**
** This opcode invokes the xFilter method on the virtual table specified
** by P1. The integer query plan parameter to xFilter is stored in register
** P3. Register P3+1 stores the argc parameter to be passed to the
** xFilter method. Registers P3+2..P3+1+argc are the argc additional
** parametersneath additional parameters which are passed to
** xFilter as argv. Register P3+2 becomes argv[0] when passed to xFilter.
**
** A jump is made to P2 if the result set after filtering would be empty.
*/
case OP_VFilter: { /* jump */
int nArg;
int iQuery;
const sqlite3_module *pModule;
Mem *pQuery = &p->aMem[pOp->p3];
Mem *pArgc = &pQuery[1];
Cursor *pCur = p->apCsr[pOp->p1];
REGISTER_TRACE(pOp->p3, pQuery);
assert( pCur->pVtabCursor );
pModule = pCur->pVtabCursor->pVtab->pModule;
/* Grab the index number and argc parameters */
assert( (pQuery->flags&MEM_Int)!=0 && pArgc->flags==MEM_Int );
nArg = pArgc->u.i;
iQuery = pQuery->u.i;
/* Invoke the xFilter method */
{
int res = 0;
int i;
Mem **apArg = p->apArg;
for(i = 0; i<nArg; i++){
apArg[i] = &pArgc[i+1];
storeTypeInfo(apArg[i], 0);
}
if( sqlite3SafetyOff(db) ) goto abort_due_to_misuse;
p->inVtabMethod = 1;
rc = pModule->xFilter(pCur->pVtabCursor, iQuery, pOp->p4.z, nArg, apArg);
p->inVtabMethod = 0;
if( rc==SQLITE_OK ){
res = pModule->xEof(pCur->pVtabCursor);
}
if( sqlite3SafetyOn(db) ) goto abort_due_to_misuse;
if( res ){
pc = pOp->p2 - 1;
}
}
pCur->nullRow = 0;
break;
}
#endif /* SQLITE_OMIT_VIRTUALTABLE */
#ifndef SQLITE_OMIT_VIRTUALTABLE
/* Opcode: VRowid P1 P2 * * *
**
** Store into register P2 the rowid of
** the virtual-table that the P1 cursor is pointing to.
*/
case OP_VRowid: { /* out2-prerelease */
const sqlite3_module *pModule;
sqlite_int64 iRow;
Cursor *pCur = p->apCsr[pOp->p1];
assert( pCur->pVtabCursor );
if( pCur->nullRow ){
break;
}
pModule = pCur->pVtabCursor->pVtab->pModule;
assert( pModule->xRowid );
if( sqlite3SafetyOff(db) ) goto abort_due_to_misuse;
rc = pModule->xRowid(pCur->pVtabCursor, &iRow);
if( sqlite3SafetyOn(db) ) goto abort_due_to_misuse;
MemSetTypeFlag(pOut, MEM_Int);
pOut->u.i = iRow;
break;
}
#endif /* SQLITE_OMIT_VIRTUALTABLE */
#ifndef SQLITE_OMIT_VIRTUALTABLE
/* Opcode: VColumn P1 P2 P3 * *
**
** Store the value of the P2-th column of
** the row of the virtual-table that the
** P1 cursor is pointing to into register P3.
*/
case OP_VColumn: {
const sqlite3_module *pModule;
Mem *pDest;
sqlite3_context sContext;
Cursor *pCur = p->apCsr[pOp->p1];
assert( pCur->pVtabCursor );
assert( pOp->p3>0 && pOp->p3<=p->nMem );
pDest = &p->aMem[pOp->p3];
if( pCur->nullRow ){
sqlite3VdbeMemSetNull(pDest);
break;
}
pModule = pCur->pVtabCursor->pVtab->pModule;
assert( pModule->xColumn );
memset(&sContext, 0, sizeof(sContext));
/* The output cell may already have a buffer allocated. Move
** the current contents to sContext.s so in case the user-function
** can use the already allocated buffer instead of allocating a
** new one.
*/
sqlite3VdbeMemMove(&sContext.s, pDest);
MemSetTypeFlag(&sContext.s, MEM_Null);
if( sqlite3SafetyOff(db) ) goto abort_due_to_misuse;
rc = pModule->xColumn(pCur->pVtabCursor, &sContext, pOp->p2);
/* Copy the result of the function to the P3 register. We
** do this regardless of whether or not an error occured to ensure any
** dynamic allocation in sContext.s (a Mem struct) is released.
*/
sqlite3VdbeChangeEncoding(&sContext.s, encoding);
REGISTER_TRACE(pOp->p3, pDest);
sqlite3VdbeMemMove(pDest, &sContext.s);
UPDATE_MAX_BLOBSIZE(pDest);
if( sqlite3SafetyOn(db) ){
goto abort_due_to_misuse;
}
if( sqlite3VdbeMemTooBig(pDest) ){
goto too_big;
}
break;
}
#endif /* SQLITE_OMIT_VIRTUALTABLE */
#ifndef SQLITE_OMIT_VIRTUALTABLE
/* Opcode: VNext P1 P2 * * *
**
** Advance virtual table P1 to the next row in its result set and
** jump to instruction P2. Or, if the virtual table has reached
** the end of its result set, then fall through to the next instruction.
*/
case OP_VNext: { /* jump */
const sqlite3_module *pModule;
int res = 0;
Cursor *pCur = p->apCsr[pOp->p1];
assert( pCur->pVtabCursor );
if( pCur->nullRow ){
break;
}
pModule = pCur->pVtabCursor->pVtab->pModule;
assert( pModule->xNext );
/* Invoke the xNext() method of the module. There is no way for the
** underlying implementation to return an error if one occurs during
** xNext(). Instead, if an error occurs, true is returned (indicating that
** data is available) and the error code returned when xColumn or
** some other method is next invoked on the save virtual table cursor.
*/
if( sqlite3SafetyOff(db) ) goto abort_due_to_misuse;
p->inVtabMethod = 1;
rc = pModule->xNext(pCur->pVtabCursor);
p->inVtabMethod = 0;
if( rc==SQLITE_OK ){
res = pModule->xEof(pCur->pVtabCursor);
}
if( sqlite3SafetyOn(db) ) goto abort_due_to_misuse;
if( !res ){
/* If there is data, jump to P2 */
pc = pOp->p2 - 1;
}
break;
}
#endif /* SQLITE_OMIT_VIRTUALTABLE */
#ifndef SQLITE_OMIT_VIRTUALTABLE
/* Opcode: VRename P1 * * P4 *
**
** P4 is a pointer to a virtual table object, an sqlite3_vtab structure.
** This opcode invokes the corresponding xRename method. The value
** in register P1 is passed as the zName argument to the xRename method.
*/
case OP_VRename: {
sqlite3_vtab *pVtab = pOp->p4.pVtab;
Mem *pName = &p->aMem[pOp->p1];
assert( pVtab->pModule->xRename );
REGISTER_TRACE(pOp->p1, pName);
Stringify(pName, encoding);
if( sqlite3SafetyOff(db) ) goto abort_due_to_misuse;
sqlite3VtabLock(pVtab);
rc = pVtab->pModule->xRename(pVtab, pName->z);
sqlite3VtabUnlock(db, pVtab);
if( sqlite3SafetyOn(db) ) goto abort_due_to_misuse;
break;
}
#endif
#ifndef SQLITE_OMIT_VIRTUALTABLE
/* Opcode: VUpdate P1 P2 P3 P4 *
**
** P4 is a pointer to a virtual table object, an sqlite3_vtab structure.
** This opcode invokes the corresponding xUpdate method. P2 values
** are contiguous memory cells starting at P3 to pass to the xUpdate
** invocation. The value in register (P3+P2-1) corresponds to the
** p2th element of the argv array passed to xUpdate.
**
** The xUpdate method will do a DELETE or an INSERT or both.
** The argv[0] element (which corresponds to memory cell P3)
** is the rowid of a row to delete. If argv[0] is NULL then no
** deletion occurs. The argv[1] element is the rowid of the new
** row. This can be NULL to have the virtual table select the new
** rowid for itself. The subsequent elements in the array are
** the values of columns in the new row.
**
** If P2==1 then no insert is performed. argv[0] is the rowid of
** a row to delete.
**
** P1 is a boolean flag. If it is set to true and the xUpdate call
** is successful, then the value returned by sqlite3_last_insert_rowid()
** is set to the value of the rowid for the row just inserted.
*/
case OP_VUpdate: {
sqlite3_vtab *pVtab = pOp->p4.pVtab;
sqlite3_module *pModule = (sqlite3_module *)pVtab->pModule;
int nArg = pOp->p2;
assert( pOp->p4type==P4_VTAB );
if( pModule->xUpdate==0 ){
sqlite3SetString(&p->zErrMsg, "read-only table", 0);
rc = SQLITE_ERROR;
}else{
int i;
sqlite_int64 rowid;
Mem **apArg = p->apArg;
Mem *pX = &p->aMem[pOp->p3];
for(i=0; i<nArg; i++){
storeTypeInfo(pX, 0);
apArg[i] = pX;
pX++;
}
if( sqlite3SafetyOff(db) ) goto abort_due_to_misuse;
sqlite3VtabLock(pVtab);
rc = pModule->xUpdate(pVtab, nArg, apArg, &rowid);
sqlite3VtabUnlock(db, pVtab);
if( sqlite3SafetyOn(db) ) goto abort_due_to_misuse;
if( pOp->p1 && rc==SQLITE_OK ){
assert( nArg>1 && apArg[0] && (apArg[0]->flags&MEM_Null) );
db->lastRowid = rowid;
}
p->nChange++;
}
break;
}
#endif /* SQLITE_OMIT_VIRTUALTABLE */
#ifndef SQLITE_OMIT_TRACE
/* Opcode: Trace * * * P4 *
**
** If tracing is enabled (by the sqlite3_trace()) interface, then
** the UTF-8 string contained in P4 is emitted on the trace callback.
*/
case OP_Trace: {
if( pOp->p4.z ){
if( db->xTrace ){
db->xTrace(db->pTraceArg, pOp->p4.z);
}
#ifdef SQLITE_DEBUG
if( (db->flags & SQLITE_SqlTrace)!=0 ){
sqlite3DebugPrintf("SQL-trace: %sn", pOp->p4.z);
}
#endif /* SQLITE_DEBUG */
}
break;
}
#endif
/* Opcode: Noop * * * * *
**
** Do nothing. This instruction is often useful as a jump
** destination.
*/
/*
** The magic Explain opcode are only inserted when explain==2 (which
** is to say when the EXPLAIN QUERY PLAN syntax is used.)
** This opcode records information from the optimizer. It is the
** the same as a no-op. This opcodesnever appears in a real VM program.
*/
default: { /* This is really OP_Noop and OP_Explain */
break;
}
/*****************************************************************************
** The cases of the switch statement above this line should all be indented
** by 6 spaces. But the left-most 6 spaces have been removed to improve the
** readability. From this point on down, the normal indentation rules are
** restored.
*****************************************************************************/
}
#ifdef VDBE_PROFILE
{
long long elapse = hwtime() - start;
pOp->cycles += elapse;
pOp->cnt++;
#if 0
fprintf(stdout, "%10lld ", elapse);
sqlite3VdbePrintOp(stdout, origPc, &p->aOp[origPc]);
#endif
}
#endif
/* The following code adds nothing to the actual functionality
** of the program. It is only here for testing and debugging.
** On the other hand, it does burn CPU cycles every time through
** the evaluator loop. So we can leave it out when NDEBUG is defined.
*/
#ifndef NDEBUG
assert( pc>=-1 && pc<p->nOp );
#ifdef SQLITE_DEBUG
if( p->trace ){
if( rc!=0 ) fprintf(p->trace,"rc=%dn",rc);
if( opProperty & OPFLG_OUT2_PRERELEASE ){
registerTrace(p->trace, pOp->p2, pOut);
}
if( opProperty & OPFLG_OUT3 ){
registerTrace(p->trace, pOp->p3, pOut);
}
}
#endif /* SQLITE_DEBUG */
#endif /* NDEBUG */
} /* The end of the for(;;) loop the loops through opcodes */
/* If we reach this point, it means that execution is finished with
** an error of some kind.
*/
vdbe_error_halt:
assert( rc );
p->rc = rc;
rc = SQLITE_ERROR;
sqlite3VdbeHalt(p);
/* This is the only way out of this procedure. We have to
** release the mutexes on btrees that were acquired at the
** top. */
vdbe_return:
sqlite3BtreeMutexArrayLeave(&p->aMutex);
return rc;
/* Jump to here if a string or blob larger than SQLITE_MAX_LENGTH
** is encountered.
*/
too_big:
sqlite3SetString(&p->zErrMsg, "string or blob too big", (char*)0);
rc = SQLITE_TOOBIG;
goto vdbe_error_halt;
/* Jump to here if a malloc() fails.
*/
no_mem:
db->mallocFailed = 1;
sqlite3SetString(&p->zErrMsg, "out of memory", (char*)0);
rc = SQLITE_NOMEM;
goto vdbe_error_halt;
/* Jump to here for an SQLITE_MISUSE error.
*/
abort_due_to_misuse:
rc = SQLITE_MISUSE;
/* Fall thru into abort_due_to_error */
/* Jump to here for any other kind of fatal error. The "rc" variable
** should hold the error number.
*/
abort_due_to_error:
assert( p->zErrMsg==0 );
if( db->mallocFailed ) rc = SQLITE_NOMEM;
sqlite3SetString(&p->zErrMsg, sqlite3ErrStr(rc), (char*)0);
goto vdbe_error_halt;
/* Jump to here if the sqlite3_interrupt() API sets the interrupt
** flag.
*/
abort_due_to_interrupt:
assert( db->u1.isInterrupted );
rc = SQLITE_INTERRUPT;
p->rc = rc;
sqlite3SetString(&p->zErrMsg, sqlite3ErrStr(rc), (char*)0);
goto vdbe_error_halt;
}