Symaptic: os/persistentdata/persistentstorage/sql/SQLite364/vdbeaux.c@bde4ae8d615e (annotated)

sl@0	1	/*
sl@0	2	** 2003 September 6
sl@0	3	**
sl@0	4	** The author disclaims copyright to this source code. In place of
sl@0	5	** a legal notice, here is a blessing:
sl@0	6	**
sl@0	7	** May you do good and not evil.
sl@0	8	** May you find forgiveness for yourself and forgive others.
sl@0	9	** May you share freely, never taking more than you give.
sl@0	10	**
sl@0	11	*************************************************************************
sl@0	12	** This file contains code used for creating, destroying, and populating
sl@0	13	** a VDBE (or an "sqlite3_stmt" as it is known to the outside world.) Prior
sl@0	14	** to version 2.8.7, all this code was combined into the vdbe.c source file.
sl@0	15	** But that file was getting too big so this subroutines were split out.
sl@0	16	**
sl@0	17	** $Id: vdbeaux.c,v 1.412 2008/10/11 17:51:39 danielk1977 Exp $
sl@0	18	*/
sl@0	19	#include "sqliteInt.h"
sl@0	20	#include <ctype.h>
sl@0	21	#include "vdbeInt.h"
sl@0	22
sl@0	23
sl@0	24
sl@0	25	/*
sl@0	26	** When debugging the code generator in a symbolic debugger, one can
sl@0	27	** set the sqlite3VdbeAddopTrace to 1 and all opcodes will be printed
sl@0	28	** as they are added to the instruction stream.
sl@0	29	*/
sl@0	30	#ifdef SQLITE_DEBUG
sl@0	31	int sqlite3VdbeAddopTrace = 0;
sl@0	32	#endif
sl@0	33
sl@0	34
sl@0	35	/*
sl@0	36	** Create a new virtual database engine.
sl@0	37	*/
sl@0	38	Vdbe sqlite3VdbeCreate(sqlite3 db){
sl@0	39	Vdbe *p;
sl@0	40	p = sqlite3DbMallocZero(db, sizeof(Vdbe) );
sl@0	41	if( p==0 ) return 0;
sl@0	42	p->db = db;
sl@0	43	if( db->pVdbe ){
sl@0	44	db->pVdbe->pPrev = p;
sl@0	45	}
sl@0	46	p->pNext = db->pVdbe;
sl@0	47	p->pPrev = 0;
sl@0	48	db->pVdbe = p;
sl@0	49	p->magic = VDBE_MAGIC_INIT;
sl@0	50	return p;
sl@0	51	}
sl@0	52
sl@0	53	/*
sl@0	54	** Remember the SQL string for a prepared statement.
sl@0	55	*/
sl@0	56	void sqlite3VdbeSetSql(Vdbe p, const char z, int n){
sl@0	57	if( p==0 ) return;
sl@0	58	assert( p->zSql==0 );
sl@0	59	p->zSql = sqlite3DbStrNDup(p->db, z, n);
sl@0	60	}
sl@0	61
sl@0	62	/*
sl@0	63	** Return the SQL associated with a prepared statement
sl@0	64	*/
sl@0	65	const char sqlite3_sql(sqlite3_stmt pStmt){
sl@0	66	return ((Vdbe *)pStmt)->zSql;
sl@0	67	}
sl@0	68
sl@0	69	/*
sl@0	70	** Swap all content between two VDBE structures.
sl@0	71	*/
sl@0	72	void sqlite3VdbeSwap(Vdbe pA, Vdbe pB){
sl@0	73	Vdbe tmp, *pTmp;
sl@0	74	char *zTmp;
sl@0	75	int nTmp;
sl@0	76	tmp = *pA;
sl@0	77	pA = pB;
sl@0	78	*pB = tmp;
sl@0	79	pTmp = pA->pNext;
sl@0	80	pA->pNext = pB->pNext;
sl@0	81	pB->pNext = pTmp;
sl@0	82	pTmp = pA->pPrev;
sl@0	83	pA->pPrev = pB->pPrev;
sl@0	84	pB->pPrev = pTmp;
sl@0	85	zTmp = pA->zSql;
sl@0	86	pA->zSql = pB->zSql;
sl@0	87	pB->zSql = zTmp;
sl@0	88	nTmp = pA->nSql;
sl@0	89	pA->nSql = pB->nSql;
sl@0	90	pB->nSql = nTmp;
sl@0	91	}
sl@0	92
sl@0	93	#ifdef SQLITE_DEBUG
sl@0	94	/*
sl@0	95	** Turn tracing on or off
sl@0	96	*/
sl@0	97	void sqlite3VdbeTrace(Vdbe p, FILE trace){
sl@0	98	p->trace = trace;
sl@0	99	}
sl@0	100	#endif
sl@0	101
sl@0	102	/*
sl@0	103	** Resize the Vdbe.aOp array so that it contains at least N
sl@0	104	** elements.
sl@0	105	**
sl@0	106	** If an out-of-memory error occurs while resizing the array,
sl@0	107	** Vdbe.aOp and Vdbe.nOpAlloc remain unchanged (this is so that
sl@0	108	** any opcodes already allocated can be correctly deallocated
sl@0	109	** along with the rest of the Vdbe).
sl@0	110	*/
sl@0	111	static void resizeOpArray(Vdbe *p, int N){
sl@0	112	VdbeOp *pNew;
sl@0	113	pNew = sqlite3DbRealloc(p->db, p->aOp, N*sizeof(Op));
sl@0	114	if( pNew ){
sl@0	115	p->nOpAlloc = N;
sl@0	116	p->aOp = pNew;
sl@0	117	}
sl@0	118	}
sl@0	119
sl@0	120	/*
sl@0	121	** Add a new instruction to the list of instructions current in the
sl@0	122	** VDBE. Return the address of the new instruction.
sl@0	123	**
sl@0	124	** Parameters:
sl@0	125	**
sl@0	126	** p Pointer to the VDBE
sl@0	127	**
sl@0	128	** op The opcode for this instruction
sl@0	129	**
sl@0	130	** p1, p2, p3 Operands
sl@0	131	**
sl@0	132	** Use the sqlite3VdbeResolveLabel() function to fix an address and
sl@0	133	** the sqlite3VdbeChangeP4() function to change the value of the P4
sl@0	134	** operand.
sl@0	135	*/
sl@0	136	int sqlite3VdbeAddOp3(Vdbe *p, int op, int p1, int p2, int p3){
sl@0	137	int i;
sl@0	138	VdbeOp *pOp;
sl@0	139
sl@0	140	i = p->nOp;
sl@0	141	assert( p->magic==VDBE_MAGIC_INIT );
sl@0	142	if( p->nOpAlloc<=i ){
sl@0	143	resizeOpArray(p, p->nOpAlloc ? p->nOpAlloc*2 : 1024/sizeof(Op));
sl@0	144	if( p->db->mallocFailed ){
sl@0	145	return 0;
sl@0	146	}
sl@0	147	}
sl@0	148	p->nOp++;
sl@0	149	pOp = &p->aOp[i];
sl@0	150	pOp->opcode = op;
sl@0	151	pOp->p5 = 0;
sl@0	152	pOp->p1 = p1;
sl@0	153	pOp->p2 = p2;
sl@0	154	pOp->p3 = p3;
sl@0	155	pOp->p4.p = 0;
sl@0	156	pOp->p4type = P4_NOTUSED;
sl@0	157	p->expired = 0;
sl@0	158	#ifdef SQLITE_DEBUG
sl@0	159	pOp->zComment = 0;
sl@0	160	if( sqlite3VdbeAddopTrace ) sqlite3VdbePrintOp(0, i, &p->aOp[i]);
sl@0	161	#endif
sl@0	162	#ifdef VDBE_PROFILE
sl@0	163	pOp->cycles = 0;
sl@0	164	pOp->cnt = 0;
sl@0	165	#endif
sl@0	166	return i;
sl@0	167	}
sl@0	168	int sqlite3VdbeAddOp0(Vdbe *p, int op){
sl@0	169	return sqlite3VdbeAddOp3(p, op, 0, 0, 0);
sl@0	170	}
sl@0	171	int sqlite3VdbeAddOp1(Vdbe *p, int op, int p1){
sl@0	172	return sqlite3VdbeAddOp3(p, op, p1, 0, 0);
sl@0	173	}
sl@0	174	int sqlite3VdbeAddOp2(Vdbe *p, int op, int p1, int p2){
sl@0	175	return sqlite3VdbeAddOp3(p, op, p1, p2, 0);
sl@0	176	}
sl@0	177
sl@0	178
sl@0	179	/*
sl@0	180	** Add an opcode that includes the p4 value as a pointer.
sl@0	181	*/
sl@0	182	int sqlite3VdbeAddOp4(
sl@0	183	Vdbe p, / Add the opcode to this VM */
sl@0	184	int op, /* The new opcode */
sl@0	185	int p1, /* The P1 operand */
sl@0	186	int p2, /* The P2 operand */
sl@0	187	int p3, /* The P3 operand */
sl@0	188	const char zP4, / The P4 operand */
sl@0	189	int p4type /* P4 operand type */
sl@0	190	){
sl@0	191	int addr = sqlite3VdbeAddOp3(p, op, p1, p2, p3);
sl@0	192	sqlite3VdbeChangeP4(p, addr, zP4, p4type);
sl@0	193	return addr;
sl@0	194	}
sl@0	195
sl@0	196	/*
sl@0	197	** Create a new symbolic label for an instruction that has yet to be
sl@0	198	** coded. The symbolic label is really just a negative number. The
sl@0	199	** label can be used as the P2 value of an operation. Later, when
sl@0	200	** the label is resolved to a specific address, the VDBE will scan
sl@0	201	** through its operation list and change all values of P2 which match
sl@0	202	** the label into the resolved address.
sl@0	203	**
sl@0	204	** The VDBE knows that a P2 value is a label because labels are
sl@0	205	** always negative and P2 values are suppose to be non-negative.
sl@0	206	** Hence, a negative P2 value is a label that has yet to be resolved.
sl@0	207	**
sl@0	208	** Zero is returned if a malloc() fails.
sl@0	209	*/
sl@0	210	int sqlite3VdbeMakeLabel(Vdbe *p){
sl@0	211	int i;
sl@0	212	i = p->nLabel++;
sl@0	213	assert( p->magic==VDBE_MAGIC_INIT );
sl@0	214	if( i>=p->nLabelAlloc ){
sl@0	215	p->nLabelAlloc = p->nLabelAlloc*2 + 10;
sl@0	216	p->aLabel = sqlite3DbReallocOrFree(p->db, p->aLabel,
sl@0	217	p->nLabelAlloc*sizeof(p->aLabel[0]));
sl@0	218	}
sl@0	219	if( p->aLabel ){
sl@0	220	p->aLabel[i] = -1;
sl@0	221	}
sl@0	222	return -1-i;
sl@0	223	}
sl@0	224
sl@0	225	/*
sl@0	226	** Resolve label "x" to be the address of the next instruction to
sl@0	227	** be inserted. The parameter "x" must have been obtained from
sl@0	228	** a prior call to sqlite3VdbeMakeLabel().
sl@0	229	*/
sl@0	230	void sqlite3VdbeResolveLabel(Vdbe *p, int x){
sl@0	231	int j = -1-x;
sl@0	232	assert( p->magic==VDBE_MAGIC_INIT );
sl@0	233	assert( j>=0 && j<p->nLabel );
sl@0	234	if( p->aLabel ){
sl@0	235	p->aLabel[j] = p->nOp;
sl@0	236	}
sl@0	237	}
sl@0	238
sl@0	239	/*
sl@0	240	** Loop through the program looking for P2 values that are negative
sl@0	241	** on jump instructions. Each such value is a label. Resolve the
sl@0	242	** label by setting the P2 value to its correct non-zero value.
sl@0	243	**
sl@0	244	** This routine is called once after all opcodes have been inserted.
sl@0	245	**
sl@0	246	** Variable *pMaxFuncArgs is set to the maximum value of any P2 argument
sl@0	247	** to an OP_Function, OP_AggStep or OP_VFilter opcode. This is used by
sl@0	248	** sqlite3VdbeMakeReady() to size the Vdbe.apArg[] array.
sl@0	249	**
sl@0	250	** This routine also does the following optimization: It scans for
sl@0	251	** instructions that might cause a statement rollback. Such instructions
sl@0	252	** are:
sl@0	253	**
sl@0	254	** * OP_Halt with P1=SQLITE_CONSTRAINT and P2=OE_Abort.
sl@0	255	** * OP_Destroy
sl@0	256	** * OP_VUpdate
sl@0	257	** * OP_VRename
sl@0	258	**
sl@0	259	** If no such instruction is found, then every Statement instruction
sl@0	260	** is changed to a Noop. In this way, we avoid creating the statement
sl@0	261	** journal file unnecessarily.
sl@0	262	*/
sl@0	263	static void resolveP2Values(Vdbe p, int pMaxFuncArgs){
sl@0	264	int i;
sl@0	265	int nMaxArgs = 0;
sl@0	266	Op *pOp;
sl@0	267	int *aLabel = p->aLabel;
sl@0	268	int doesStatementRollback = 0;
sl@0	269	int hasStatementBegin = 0;
sl@0	270	for(pOp=p->aOp, i=p->nOp-1; i>=0; i--, pOp++){
sl@0	271	u8 opcode = pOp->opcode;
sl@0	272
sl@0	273	if( opcode==OP_Function \|\| opcode==OP_AggStep ){
sl@0	274	if( pOp->p5>nMaxArgs ) nMaxArgs = pOp->p5;
sl@0	275	#ifndef SQLITE_OMIT_VIRTUALTABLE
sl@0	276	}else if( opcode==OP_VUpdate ){
sl@0	277	if( pOp->p2>nMaxArgs ) nMaxArgs = pOp->p2;
sl@0	278	#endif
sl@0	279	}
sl@0	280	if( opcode==OP_Halt ){
sl@0	281	if( pOp->p1==SQLITE_CONSTRAINT && pOp->p2==OE_Abort ){
sl@0	282	doesStatementRollback = 1;
sl@0	283	}
sl@0	284	}else if( opcode==OP_Statement ){
sl@0	285	hasStatementBegin = 1;
sl@0	286	}else if( opcode==OP_Destroy ){
sl@0	287	doesStatementRollback = 1;
sl@0	288	#ifndef SQLITE_OMIT_VIRTUALTABLE
sl@0	289	}else if( opcode==OP_VUpdate \|\| opcode==OP_VRename ){
sl@0	290	doesStatementRollback = 1;
sl@0	291	}else if( opcode==OP_VFilter ){
sl@0	292	int n;
sl@0	293	assert( p->nOp - i >= 3 );
sl@0	294	assert( pOp[-1].opcode==OP_Integer );
sl@0	295	n = pOp[-1].p1;
sl@0	296	if( n>nMaxArgs ) nMaxArgs = n;
sl@0	297	#endif
sl@0	298	}
sl@0	299
sl@0	300	if( sqlite3VdbeOpcodeHasProperty(opcode, OPFLG_JUMP) && pOp->p2<0 ){
sl@0	301	assert( -1-pOp->p2<p->nLabel );
sl@0	302	pOp->p2 = aLabel[-1-pOp->p2];
sl@0	303	}
sl@0	304	}
sl@0	305	sqlite3DbFree(p->db, p->aLabel);
sl@0	306	p->aLabel = 0;
sl@0	307
sl@0	308	*pMaxFuncArgs = nMaxArgs;
sl@0	309
sl@0	310	/* If we never rollback a statement transaction, then statement
sl@0	311	** transactions are not needed. So change every OP_Statement
sl@0	312	** opcode into an OP_Noop. This avoid a call to sqlite3OsOpenExclusive()
sl@0	313	** which can be expensive on some platforms.
sl@0	314	*/
sl@0	315	if( hasStatementBegin && !doesStatementRollback ){
sl@0	316	for(pOp=p->aOp, i=p->nOp-1; i>=0; i--, pOp++){
sl@0	317	if( pOp->opcode==OP_Statement ){
sl@0	318	pOp->opcode = OP_Noop;
sl@0	319	}
sl@0	320	}
sl@0	321	}
sl@0	322	}
sl@0	323
sl@0	324	/*
sl@0	325	** Return the address of the next instruction to be inserted.
sl@0	326	*/
sl@0	327	int sqlite3VdbeCurrentAddr(Vdbe *p){
sl@0	328	assert( p->magic==VDBE_MAGIC_INIT );
sl@0	329	return p->nOp;
sl@0	330	}
sl@0	331
sl@0	332	/*
sl@0	333	** Add a whole list of operations to the operation stack. Return the
sl@0	334	** address of the first operation added.
sl@0	335	*/
sl@0	336	int sqlite3VdbeAddOpList(Vdbe p, int nOp, VdbeOpList const aOp){
sl@0	337	int addr;
sl@0	338	assert( p->magic==VDBE_MAGIC_INIT );
sl@0	339	if( p->nOp + nOp > p->nOpAlloc ){
sl@0	340	resizeOpArray(p, p->nOpAlloc ? p->nOpAlloc*2 : 1024/sizeof(Op));
sl@0	341	assert( p->nOp+nOp<=p->nOpAlloc \|\| p->db->mallocFailed );
sl@0	342	}
sl@0	343	if( p->db->mallocFailed ){
sl@0	344	return 0;
sl@0	345	}
sl@0	346	addr = p->nOp;
sl@0	347	if( nOp>0 ){
sl@0	348	int i;
sl@0	349	VdbeOpList const *pIn = aOp;
sl@0	350	for(i=0; i<nOp; i++, pIn++){
sl@0	351	int p2 = pIn->p2;
sl@0	352	VdbeOp *pOut = &p->aOp[i+addr];
sl@0	353	pOut->opcode = pIn->opcode;
sl@0	354	pOut->p1 = pIn->p1;
sl@0	355	if( p2<0 && sqlite3VdbeOpcodeHasProperty(pOut->opcode, OPFLG_JUMP) ){
sl@0	356	pOut->p2 = addr + ADDR(p2);
sl@0	357	}else{
sl@0	358	pOut->p2 = p2;
sl@0	359	}
sl@0	360	pOut->p3 = pIn->p3;
sl@0	361	pOut->p4type = P4_NOTUSED;
sl@0	362	pOut->p4.p = 0;
sl@0	363	pOut->p5 = 0;
sl@0	364	#ifdef SQLITE_DEBUG
sl@0	365	pOut->zComment = 0;
sl@0	366	if( sqlite3VdbeAddopTrace ){
sl@0	367	sqlite3VdbePrintOp(0, i+addr, &p->aOp[i+addr]);
sl@0	368	}
sl@0	369	#endif
sl@0	370	}
sl@0	371	p->nOp += nOp;
sl@0	372	}
sl@0	373	return addr;
sl@0	374	}
sl@0	375
sl@0	376	/*
sl@0	377	** Change the value of the P1 operand for a specific instruction.
sl@0	378	** This routine is useful when a large program is loaded from a
sl@0	379	** static array using sqlite3VdbeAddOpList but we want to make a
sl@0	380	** few minor changes to the program.
sl@0	381	*/
sl@0	382	void sqlite3VdbeChangeP1(Vdbe *p, int addr, int val){
sl@0	383	assert( p==0 \|\| p->magic==VDBE_MAGIC_INIT );
sl@0	384	if( p && addr>=0 && p->nOp>addr && p->aOp ){
sl@0	385	p->aOp[addr].p1 = val;
sl@0	386	}
sl@0	387	}
sl@0	388
sl@0	389	/*
sl@0	390	** Change the value of the P2 operand for a specific instruction.
sl@0	391	** This routine is useful for setting a jump destination.
sl@0	392	*/
sl@0	393	void sqlite3VdbeChangeP2(Vdbe *p, int addr, int val){
sl@0	394	assert( p==0 \|\| p->magic==VDBE_MAGIC_INIT );
sl@0	395	if( p && addr>=0 && p->nOp>addr && p->aOp ){
sl@0	396	p->aOp[addr].p2 = val;
sl@0	397	}
sl@0	398	}
sl@0	399
sl@0	400	/*
sl@0	401	** Change the value of the P3 operand for a specific instruction.
sl@0	402	*/
sl@0	403	void sqlite3VdbeChangeP3(Vdbe *p, int addr, int val){
sl@0	404	assert( p==0 \|\| p->magic==VDBE_MAGIC_INIT );
sl@0	405	if( p && addr>=0 && p->nOp>addr && p->aOp ){
sl@0	406	p->aOp[addr].p3 = val;
sl@0	407	}
sl@0	408	}
sl@0	409
sl@0	410	/*
sl@0	411	** Change the value of the P5 operand for the most recently
sl@0	412	** added operation.
sl@0	413	*/
sl@0	414	void sqlite3VdbeChangeP5(Vdbe *p, u8 val){
sl@0	415	assert( p==0 \|\| p->magic==VDBE_MAGIC_INIT );
sl@0	416	if( p && p->aOp ){
sl@0	417	assert( p->nOp>0 );
sl@0	418	p->aOp[p->nOp-1].p5 = val;
sl@0	419	}
sl@0	420	}
sl@0	421
sl@0	422	/*
sl@0	423	** Change the P2 operand of instruction addr so that it points to
sl@0	424	** the address of the next instruction to be coded.
sl@0	425	*/
sl@0	426	void sqlite3VdbeJumpHere(Vdbe *p, int addr){
sl@0	427	sqlite3VdbeChangeP2(p, addr, p->nOp);
sl@0	428	}
sl@0	429
sl@0	430
sl@0	431	/*
sl@0	432	** If the input FuncDef structure is ephemeral, then free it. If
sl@0	433	** the FuncDef is not ephermal, then do nothing.
sl@0	434	*/
sl@0	435	static void freeEphemeralFunction(sqlite3 db, FuncDef pDef){
sl@0	436	if( pDef && (pDef->flags & SQLITE_FUNC_EPHEM)!=0 ){
sl@0	437	sqlite3DbFree(db, pDef);
sl@0	438	}
sl@0	439	}
sl@0	440
sl@0	441	/*
sl@0	442	** Delete a P4 value if necessary.
sl@0	443	*/
sl@0	444	static void freeP4(sqlite3 db, int p4type, void p4){
sl@0	445	if( p4 ){
sl@0	446	switch( p4type ){
sl@0	447	case P4_REAL:
sl@0	448	case P4_INT64:
sl@0	449	case P4_MPRINTF:
sl@0	450	case P4_DYNAMIC:
sl@0	451	case P4_KEYINFO:
sl@0	452	case P4_INTARRAY:
sl@0	453	case P4_KEYINFO_HANDOFF: {
sl@0	454	sqlite3DbFree(db, p4);
sl@0	455	break;
sl@0	456	}
sl@0	457	case P4_VDBEFUNC: {
sl@0	458	VdbeFunc pVdbeFunc = (VdbeFunc )p4;
sl@0	459	freeEphemeralFunction(db, pVdbeFunc->pFunc);
sl@0	460	sqlite3VdbeDeleteAuxData(pVdbeFunc, 0);
sl@0	461	sqlite3DbFree(db, pVdbeFunc);
sl@0	462	break;
sl@0	463	}
sl@0	464	case P4_FUNCDEF: {
sl@0	465	freeEphemeralFunction(db, (FuncDef*)p4);
sl@0	466	break;
sl@0	467	}
sl@0	468	case P4_MEM: {
sl@0	469	sqlite3ValueFree((sqlite3_value*)p4);
sl@0	470	break;
sl@0	471	}
sl@0	472	}
sl@0	473	}
sl@0	474	}
sl@0	475
sl@0	476
sl@0	477	/*
sl@0	478	** Change N opcodes starting at addr to No-ops.
sl@0	479	*/
sl@0	480	void sqlite3VdbeChangeToNoop(Vdbe *p, int addr, int N){
sl@0	481	if( p && p->aOp ){
sl@0	482	VdbeOp *pOp = &p->aOp[addr];
sl@0	483	sqlite3 *db = p->db;
sl@0	484	while( N-- ){
sl@0	485	freeP4(db, pOp->p4type, pOp->p4.p);
sl@0	486	memset(pOp, 0, sizeof(pOp[0]));
sl@0	487	pOp->opcode = OP_Noop;
sl@0	488	pOp++;
sl@0	489	}
sl@0	490	}
sl@0	491	}
sl@0	492
sl@0	493	/*
sl@0	494	** Change the value of the P4 operand for a specific instruction.
sl@0	495	** This routine is useful when a large program is loaded from a
sl@0	496	** static array using sqlite3VdbeAddOpList but we want to make a
sl@0	497	** few minor changes to the program.
sl@0	498	**
sl@0	499	** If n>=0 then the P4 operand is dynamic, meaning that a copy of
sl@0	500	** the string is made into memory obtained from sqlite3_malloc().
sl@0	501	** A value of n==0 means copy bytes of zP4 up to and including the
sl@0	502	** first null byte. If n>0 then copy n+1 bytes of zP4.
sl@0	503	**
sl@0	504	** If n==P4_KEYINFO it means that zP4 is a pointer to a KeyInfo structure.
sl@0	505	** A copy is made of the KeyInfo structure into memory obtained from
sl@0	506	** sqlite3_malloc, to be freed when the Vdbe is finalized.
sl@0	507	** n==P4_KEYINFO_HANDOFF indicates that zP4 points to a KeyInfo structure
sl@0	508	** stored in memory that the caller has obtained from sqlite3_malloc. The
sl@0	509	** caller should not free the allocation, it will be freed when the Vdbe is
sl@0	510	** finalized.
sl@0	511	**
sl@0	512	** Other values of n (P4_STATIC, P4_COLLSEQ etc.) indicate that zP4 points
sl@0	513	** to a string or structure that is guaranteed to exist for the lifetime of
sl@0	514	** the Vdbe. In these cases we can just copy the pointer.
sl@0	515	**
sl@0	516	** If addr<0 then change P4 on the most recently inserted instruction.
sl@0	517	*/
sl@0	518	void sqlite3VdbeChangeP4(Vdbe p, int addr, const char zP4, int n){
sl@0	519	Op *pOp;
sl@0	520	sqlite3 *db;
sl@0	521	assert( p!=0 );
sl@0	522	db = p->db;
sl@0	523	assert( p->magic==VDBE_MAGIC_INIT );
sl@0	524	if( p->aOp==0 \|\| db->mallocFailed ){
sl@0	525	if (n != P4_KEYINFO) {
sl@0	526	freeP4(db, n, (void)(char**)&zP4);
sl@0	527	}
sl@0	528	return;
sl@0	529	}
sl@0	530	assert( addr<p->nOp );
sl@0	531	if( addr<0 ){
sl@0	532	addr = p->nOp - 1;
sl@0	533	if( addr<0 ) return;
sl@0	534	}
sl@0	535	pOp = &p->aOp[addr];
sl@0	536	freeP4(db, pOp->p4type, pOp->p4.p);
sl@0	537	pOp->p4.p = 0;
sl@0	538	if( n==P4_INT32 ){
sl@0	539	/* Note: this cast is safe, because the origin data point was an int
sl@0	540	** that was cast to a (const char ). /
sl@0	541	pOp->p4.i = SQLITE_PTR_TO_INT(zP4);
sl@0	542	pOp->p4type = n;
sl@0	543	}else if( zP4==0 ){
sl@0	544	pOp->p4.p = 0;
sl@0	545	pOp->p4type = P4_NOTUSED;
sl@0	546	}else if( n==P4_KEYINFO ){
sl@0	547	KeyInfo *pKeyInfo;
sl@0	548	int nField, nByte;
sl@0	549
sl@0	550	nField = ((KeyInfo*)zP4)->nField;
sl@0	551	nByte = sizeof(pKeyInfo) + (nField-1)sizeof(pKeyInfo->aColl[0]) + nField;
sl@0	552	pKeyInfo = sqlite3Malloc( nByte );
sl@0	553	pOp->p4.pKeyInfo = pKeyInfo;
sl@0	554	if( pKeyInfo ){
sl@0	555	u8 *aSortOrder;
sl@0	556	memcpy(pKeyInfo, zP4, nByte);
sl@0	557	aSortOrder = pKeyInfo->aSortOrder;
sl@0	558	if( aSortOrder ){
sl@0	559	pKeyInfo->aSortOrder = (unsigned char*)&pKeyInfo->aColl[nField];
sl@0	560	memcpy(pKeyInfo->aSortOrder, aSortOrder, nField);
sl@0	561	}
sl@0	562	pOp->p4type = P4_KEYINFO;
sl@0	563	}else{
sl@0	564	p->db->mallocFailed = 1;
sl@0	565	pOp->p4type = P4_NOTUSED;
sl@0	566	}
sl@0	567	}else if( n==P4_KEYINFO_HANDOFF ){
sl@0	568	pOp->p4.p = (void*)zP4;
sl@0	569	pOp->p4type = P4_KEYINFO;
sl@0	570	}else if( n<0 ){
sl@0	571	pOp->p4.p = (void*)zP4;
sl@0	572	pOp->p4type = n;
sl@0	573	}else{
sl@0	574	if( n==0 ) n = strlen(zP4);
sl@0	575	pOp->p4.z = sqlite3DbStrNDup(p->db, zP4, n);
sl@0	576	pOp->p4type = P4_DYNAMIC;
sl@0	577	}
sl@0	578	}
sl@0	579
sl@0	580	#ifndef NDEBUG
sl@0	581	/*
sl@0	582	** Change the comment on the the most recently coded instruction. Or
sl@0	583	** insert a No-op and add the comment to that new instruction. This
sl@0	584	** makes the code easier to read during debugging. None of this happens
sl@0	585	** in a production build.
sl@0	586	*/
sl@0	587	void sqlite3VdbeComment(Vdbe p, const char zFormat, ...){
sl@0	588	va_list ap;
sl@0	589	assert( p->nOp>0 \|\| p->aOp==0 );
sl@0	590	assert( p->aOp==0 \|\| p->aOp[p->nOp-1].zComment==0 \|\| p->db->mallocFailed );
sl@0	591	if( p->nOp ){
sl@0	592	char **pz = &p->aOp[p->nOp-1].zComment;
sl@0	593	va_start(ap, zFormat);
sl@0	594	sqlite3DbFree(p->db, *pz);
sl@0	595	*pz = sqlite3VMPrintf(p->db, zFormat, ap);
sl@0	596	va_end(ap);
sl@0	597	}
sl@0	598	}
sl@0	599	void sqlite3VdbeNoopComment(Vdbe p, const char zFormat, ...){
sl@0	600	va_list ap;
sl@0	601	sqlite3VdbeAddOp0(p, OP_Noop);
sl@0	602	assert( p->nOp>0 \|\| p->aOp==0 );
sl@0	603	assert( p->aOp==0 \|\| p->aOp[p->nOp-1].zComment==0 \|\| p->db->mallocFailed );
sl@0	604	if( p->nOp ){
sl@0	605	char **pz = &p->aOp[p->nOp-1].zComment;
sl@0	606	va_start(ap, zFormat);
sl@0	607	sqlite3DbFree(p->db, *pz);
sl@0	608	*pz = sqlite3VMPrintf(p->db, zFormat, ap);
sl@0	609	va_end(ap);
sl@0	610	}
sl@0	611	}
sl@0	612	#endif /* NDEBUG */
sl@0	613
sl@0	614	/*
sl@0	615	** Return the opcode for a given address.
sl@0	616	*/
sl@0	617	VdbeOp sqlite3VdbeGetOp(Vdbe p, int addr){
sl@0	618	assert( p->magic==VDBE_MAGIC_INIT );
sl@0	619	assert( (addr>=0 && addr<p->nOp) \|\| p->db->mallocFailed );
sl@0	620	return ((addr>=0 && addr<p->nOp)?(&p->aOp[addr]):0);
sl@0	621	}
sl@0	622
sl@0	623	#if !defined(SQLITE_OMIT_EXPLAIN) \|\| !defined(NDEBUG) \
sl@0	624	\|\| defined(VDBE_PROFILE) \|\| defined(SQLITE_DEBUG)
sl@0	625	/*
sl@0	626	** Compute a string that describes the P4 parameter for an opcode.
sl@0	627	** Use zTemp for any required temporary buffer space.
sl@0	628	*/
sl@0	629	static char displayP4(Op pOp, char *zTemp, int nTemp){
sl@0	630	char *zP4 = zTemp;
sl@0	631	assert( nTemp>=20 );
sl@0	632	switch( pOp->p4type ){
sl@0	633	case P4_KEYINFO_STATIC:
sl@0	634	case P4_KEYINFO: {
sl@0	635	int i, j;
sl@0	636	KeyInfo *pKeyInfo = pOp->p4.pKeyInfo;
sl@0	637	sqlite3_snprintf(nTemp, zTemp, "keyinfo(%d", pKeyInfo->nField);
sl@0	638	i = strlen(zTemp);
sl@0	639	for(j=0; j<pKeyInfo->nField; j++){
sl@0	640	CollSeq *pColl = pKeyInfo->aColl[j];
sl@0	641	if( pColl ){
sl@0	642	int n = strlen(pColl->zName);
sl@0	643	if( i+n>nTemp-6 ){
sl@0	644	memcpy(&zTemp[i],",...",4);
sl@0	645	break;
sl@0	646	}
sl@0	647	zTemp[i++] = ',';
sl@0	648	if( pKeyInfo->aSortOrder && pKeyInfo->aSortOrder[j] ){
sl@0	649	zTemp[i++] = '-';
sl@0	650	}
sl@0	651	memcpy(&zTemp[i], pColl->zName,n+1);
sl@0	652	i += n;
sl@0	653	}else if( i+4<nTemp-6 ){
sl@0	654	memcpy(&zTemp[i],",nil",4);
sl@0	655	i += 4;
sl@0	656	}
sl@0	657	}
sl@0	658	zTemp[i++] = ')';
sl@0	659	zTemp[i] = 0;
sl@0	660	assert( i<nTemp );
sl@0	661	break;
sl@0	662	}
sl@0	663	case P4_COLLSEQ: {
sl@0	664	CollSeq *pColl = pOp->p4.pColl;
sl@0	665	sqlite3_snprintf(nTemp, zTemp, "collseq(%.20s)", pColl->zName);
sl@0	666	break;
sl@0	667	}
sl@0	668	case P4_FUNCDEF: {
sl@0	669	FuncDef *pDef = pOp->p4.pFunc;
sl@0	670	sqlite3_snprintf(nTemp, zTemp, "%s(%d)", pDef->zName, pDef->nArg);
sl@0	671	break;
sl@0	672	}
sl@0	673	case P4_INT64: {
sl@0	674	sqlite3_snprintf(nTemp, zTemp, "%lld", *pOp->p4.pI64);
sl@0	675	break;
sl@0	676	}
sl@0	677	case P4_INT32: {
sl@0	678	sqlite3_snprintf(nTemp, zTemp, "%d", pOp->p4.i);
sl@0	679	break;
sl@0	680	}
sl@0	681	case P4_REAL: {
sl@0	682	sqlite3_snprintf(nTemp, zTemp, "%.16g", *pOp->p4.pReal);
sl@0	683	break;
sl@0	684	}
sl@0	685	case P4_MEM: {
sl@0	686	Mem *pMem = pOp->p4.pMem;
sl@0	687	assert( (pMem->flags & MEM_Null)==0 );
sl@0	688	if( pMem->flags & MEM_Str ){
sl@0	689	zP4 = pMem->z;
sl@0	690	}else if( pMem->flags & MEM_Int ){
sl@0	691	sqlite3_snprintf(nTemp, zTemp, "%lld", pMem->u.i);
sl@0	692	}else if( pMem->flags & MEM_Real ){
sl@0	693	sqlite3_snprintf(nTemp, zTemp, "%.16g", pMem->r);
sl@0	694	}
sl@0	695	break;
sl@0	696	}
sl@0	697	#ifndef SQLITE_OMIT_VIRTUALTABLE
sl@0	698	case P4_VTAB: {
sl@0	699	sqlite3_vtab *pVtab = pOp->p4.pVtab;
sl@0	700	sqlite3_snprintf(nTemp, zTemp, "vtab:%p:%p", pVtab, pVtab->pModule);
sl@0	701	break;
sl@0	702	}
sl@0	703	#endif
sl@0	704	case P4_INTARRAY: {
sl@0	705	sqlite3_snprintf(nTemp, zTemp, "intarray");
sl@0	706	break;
sl@0	707	}
sl@0	708	default: {
sl@0	709	zP4 = pOp->p4.z;
sl@0	710	if( zP4==0 ){
sl@0	711	zP4 = zTemp;
sl@0	712	zTemp[0] = 0;
sl@0	713	}
sl@0	714	}
sl@0	715	}
sl@0	716	assert( zP4!=0 );
sl@0	717	return zP4;
sl@0	718	}
sl@0	719	#endif
sl@0	720
sl@0	721	/*
sl@0	722	** Declare to the Vdbe that the BTree object at db->aDb[i] is used.
sl@0	723	**
sl@0	724	*/
sl@0	725	void sqlite3VdbeUsesBtree(Vdbe *p, int i){
sl@0	726	int mask;
sl@0	727	assert( i>=0 && i<p->db->nDb );
sl@0	728	assert( i<sizeof(p->btreeMask)*8 );
sl@0	729	mask = 1<<i;
sl@0	730	if( (p->btreeMask & mask)==0 ){
sl@0	731	p->btreeMask \|= mask;
sl@0	732	sqlite3BtreeMutexArrayInsert(&p->aMutex, p->db->aDb[i].pBt);
sl@0	733	}
sl@0	734	}
sl@0	735
sl@0	736
sl@0	737	#if defined(VDBE_PROFILE) \|\| defined(SQLITE_DEBUG)
sl@0	738	/*
sl@0	739	** Print a single opcode. This routine is used for debugging only.
sl@0	740	*/
sl@0	741	void sqlite3VdbePrintOp(FILE pOut, int pc, Op pOp){
sl@0	742	char *zP4;
sl@0	743	char zPtr[50];
sl@0	744	static const char *zFormat1 = "%4d %-13s %4d %4d %4d %-4s %.2X %s\n";
sl@0	745	if( pOut==0 ) pOut = stdout;
sl@0	746	zP4 = displayP4(pOp, zPtr, sizeof(zPtr));
sl@0	747	fprintf(pOut, zFormat1, pc,
sl@0	748	sqlite3OpcodeName(pOp->opcode), pOp->p1, pOp->p2, pOp->p3, zP4, pOp->p5,
sl@0	749	#ifdef SQLITE_DEBUG
sl@0	750	pOp->zComment ? pOp->zComment : ""
sl@0	751	#else
sl@0	752	""
sl@0	753	#endif
sl@0	754	);
sl@0	755	fflush(pOut);
sl@0	756	}
sl@0	757	#endif
sl@0	758
sl@0	759	/*
sl@0	760	** Release an array of N Mem elements
sl@0	761	*/
sl@0	762	static void releaseMemArray(Mem *p, int N){
sl@0	763	if( p && N ){
sl@0	764	Mem *pEnd;
sl@0	765	sqlite3 *db = p->db;
sl@0	766	int malloc_failed = db->mallocFailed;
sl@0	767	for(pEnd=&p[N]; p<pEnd; p++){
sl@0	768	assert( (&p[1])==pEnd \|\| p[0].db==p[1].db );
sl@0	769
sl@0	770	/* This block is really an inlined version of sqlite3VdbeMemRelease()
sl@0	771	** that takes advantage of the fact that the memory cell value is
sl@0	772	** being set to NULL after releasing any dynamic resources.
sl@0	773	**
sl@0	774	** The justification for duplicating code is that according to
sl@0	775	** callgrind, this causes a certain test case to hit the CPU 4.7
sl@0	776	** percent less (x86 linux, gcc version 4.1.2, -O6) than if
sl@0	777	** sqlite3MemRelease() were called from here. With -O2, this jumps
sl@0	778	** to 6.6 percent. The test case is inserting 1000 rows into a table
sl@0	779	** with no indexes using a single prepared INSERT statement, bind()
sl@0	780	** and reset(). Inserts are grouped into a transaction.
sl@0	781	*/
sl@0	782	if( p->flags&(MEM_Agg\|MEM_Dyn) ){
sl@0	783	sqlite3VdbeMemRelease(p);
sl@0	784	}else if( p->zMalloc ){
sl@0	785	sqlite3DbFree(db, p->zMalloc);
sl@0	786	p->zMalloc = 0;
sl@0	787	}
sl@0	788
sl@0	789	p->flags = MEM_Null;
sl@0	790	}
sl@0	791	db->mallocFailed = malloc_failed;
sl@0	792	}
sl@0	793	}
sl@0	794
sl@0	795	#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
sl@0	796	int sqlite3VdbeReleaseBuffers(Vdbe *p){
sl@0	797	int ii;
sl@0	798	int nFree = 0;
sl@0	799	assert( sqlite3_mutex_held(p->db->mutex) );
sl@0	800	for(ii=1; ii<=p->nMem; ii++){
sl@0	801	Mem *pMem = &p->aMem[ii];
sl@0	802	if( pMem->z && pMem->flags&MEM_Dyn ){
sl@0	803	assert( !pMem->xDel );
sl@0	804	nFree += sqlite3DbMallocSize(pMem->db, pMem->z);
sl@0	805	sqlite3VdbeMemRelease(pMem);
sl@0	806	}
sl@0	807	}
sl@0	808	return nFree;
sl@0	809	}
sl@0	810	#endif
sl@0	811
sl@0	812	#ifndef SQLITE_OMIT_EXPLAIN
sl@0	813	/*
sl@0	814	** Give a listing of the program in the virtual machine.
sl@0	815	**
sl@0	816	** The interface is the same as sqlite3VdbeExec(). But instead of
sl@0	817	** running the code, it invokes the callback once for each instruction.
sl@0	818	** This feature is used to implement "EXPLAIN".
sl@0	819	**
sl@0	820	** When p->explain==1, each instruction is listed. When
sl@0	821	** p->explain==2, only OP_Explain instructions are listed and these
sl@0	822	** are shown in a different format. p->explain==2 is used to implement
sl@0	823	** EXPLAIN QUERY PLAN.
sl@0	824	*/
sl@0	825	int sqlite3VdbeList(
sl@0	826	Vdbe p / The VDBE */
sl@0	827	){
sl@0	828	sqlite3 *db = p->db;
sl@0	829	int i;
sl@0	830	int rc = SQLITE_OK;
sl@0	831	Mem *pMem = p->pResultSet = &p->aMem[1];
sl@0	832
sl@0	833	assert( p->explain );
sl@0	834	if( p->magic!=VDBE_MAGIC_RUN ) return SQLITE_MISUSE;
sl@0	835	assert( db->magic==SQLITE_MAGIC_BUSY );
sl@0	836	assert( p->rc==SQLITE_OK \|\| p->rc==SQLITE_BUSY );
sl@0	837
sl@0	838	/* Even though this opcode does not use dynamic strings for
sl@0	839	** the result, result columns may become dynamic if the user calls
sl@0	840	** sqlite3_column_text16(), causing a translation to UTF-16 encoding.
sl@0	841	*/
sl@0	842	releaseMemArray(pMem, p->nMem);
sl@0	843
sl@0	844	do{
sl@0	845	i = p->pc++;
sl@0	846	}while( i<p->nOp && p->explain==2 && p->aOp[i].opcode!=OP_Explain );
sl@0	847	if( i>=p->nOp ){
sl@0	848	p->rc = SQLITE_OK;
sl@0	849	rc = SQLITE_DONE;
sl@0	850	}else if( db->u1.isInterrupted ){
sl@0	851	p->rc = SQLITE_INTERRUPT;
sl@0	852	rc = SQLITE_ERROR;
sl@0	853	sqlite3SetString(&p->zErrMsg, db, "%s", sqlite3ErrStr(p->rc));
sl@0	854	}else{
sl@0	855	char *z;
sl@0	856	Op *pOp = &p->aOp[i];
sl@0	857	if( p->explain==1 ){
sl@0	858	pMem->flags = MEM_Int;
sl@0	859	pMem->type = SQLITE_INTEGER;
sl@0	860	pMem->u.i = i; /* Program counter */
sl@0	861	pMem++;
sl@0	862
sl@0	863	pMem->flags = MEM_Static\|MEM_Str\|MEM_Term;
sl@0	864	pMem->z = (char)sqlite3OpcodeName(pOp->opcode); / Opcode */
sl@0	865	assert( pMem->z!=0 );
sl@0	866	pMem->n = strlen(pMem->z);
sl@0	867	pMem->type = SQLITE_TEXT;
sl@0	868	pMem->enc = SQLITE_UTF8;
sl@0	869	pMem++;
sl@0	870	}
sl@0	871
sl@0	872	pMem->flags = MEM_Int;
sl@0	873	pMem->u.i = pOp->p1; /* P1 */
sl@0	874	pMem->type = SQLITE_INTEGER;
sl@0	875	pMem++;
sl@0	876
sl@0	877	pMem->flags = MEM_Int;
sl@0	878	pMem->u.i = pOp->p2; /* P2 */
sl@0	879	pMem->type = SQLITE_INTEGER;
sl@0	880	pMem++;
sl@0	881
sl@0	882	if( p->explain==1 ){
sl@0	883	pMem->flags = MEM_Int;
sl@0	884	pMem->u.i = pOp->p3; /* P3 */
sl@0	885	pMem->type = SQLITE_INTEGER;
sl@0	886	pMem++;
sl@0	887	}
sl@0	888
sl@0	889	if( sqlite3VdbeMemGrow(pMem, 32, 0) ){ /* P4 */
sl@0	890	p->db->mallocFailed = 1;
sl@0	891	return SQLITE_NOMEM;
sl@0	892	}
sl@0	893	pMem->flags = MEM_Dyn\|MEM_Str\|MEM_Term;
sl@0	894	z = displayP4(pOp, pMem->z, 32);
sl@0	895	if( z!=pMem->z ){
sl@0	896	sqlite3VdbeMemSetStr(pMem, z, -1, SQLITE_UTF8, 0);
sl@0	897	}else{
sl@0	898	assert( pMem->z!=0 );
sl@0	899	pMem->n = strlen(pMem->z);
sl@0	900	pMem->enc = SQLITE_UTF8;
sl@0	901	}
sl@0	902	pMem->type = SQLITE_TEXT;
sl@0	903	pMem++;
sl@0	904
sl@0	905	if( p->explain==1 ){
sl@0	906	if( sqlite3VdbeMemGrow(pMem, 4, 0) ){
sl@0	907	p->db->mallocFailed = 1;
sl@0	908	return SQLITE_NOMEM;
sl@0	909	}
sl@0	910	pMem->flags = MEM_Dyn\|MEM_Str\|MEM_Term;
sl@0	911	pMem->n = 2;
sl@0	912	sqlite3_snprintf(3, pMem->z, "%.2x", pOp->p5); /* P5 */
sl@0	913	pMem->type = SQLITE_TEXT;
sl@0	914	pMem->enc = SQLITE_UTF8;
sl@0	915	pMem++;
sl@0	916
sl@0	917	#ifdef SQLITE_DEBUG
sl@0	918	if( pOp->zComment ){
sl@0	919	pMem->flags = MEM_Str\|MEM_Term;
sl@0	920	pMem->z = pOp->zComment;
sl@0	921	pMem->n = strlen(pMem->z);
sl@0	922	pMem->enc = SQLITE_UTF8;
sl@0	923	pMem->type = SQLITE_TEXT;
sl@0	924	}else
sl@0	925	#endif
sl@0	926	{
sl@0	927	pMem->flags = MEM_Null; /* Comment */
sl@0	928	pMem->type = SQLITE_NULL;
sl@0	929	}
sl@0	930	}
sl@0	931
sl@0	932	p->nResColumn = 8 - 5*(p->explain-1);
sl@0	933	p->rc = SQLITE_OK;
sl@0	934	rc = SQLITE_ROW;
sl@0	935	}
sl@0	936	return rc;
sl@0	937	}
sl@0	938	#endif /* SQLITE_OMIT_EXPLAIN */
sl@0	939
sl@0	940	#ifdef SQLITE_DEBUG
sl@0	941	/*
sl@0	942	** Print the SQL that was used to generate a VDBE program.
sl@0	943	*/
sl@0	944	void sqlite3VdbePrintSql(Vdbe *p){
sl@0	945	int nOp = p->nOp;
sl@0	946	VdbeOp *pOp;
sl@0	947	if( nOp<1 ) return;
sl@0	948	pOp = &p->aOp[0];
sl@0	949	if( pOp->opcode==OP_Trace && pOp->p4.z!=0 ){
sl@0	950	const char *z = pOp->p4.z;
sl@0	951	while( isspace((u8)z) ) z++;
sl@0	952	printf("SQL: [%s]\n", z);
sl@0	953	}
sl@0	954	}
sl@0	955	#endif
sl@0	956
sl@0	957	#if !defined(SQLITE_OMIT_TRACE) && defined(SQLITE_ENABLE_IOTRACE)
sl@0	958	/*
sl@0	959	** Print an IOTRACE message showing SQL content.
sl@0	960	*/
sl@0	961	void sqlite3VdbeIOTraceSql(Vdbe *p){
sl@0	962	int nOp = p->nOp;
sl@0	963	VdbeOp *pOp;
sl@0	964	if( sqlite3IoTrace==0 ) return;
sl@0	965	if( nOp<1 ) return;
sl@0	966	pOp = &p->aOp[0];
sl@0	967	if( pOp->opcode==OP_Trace && pOp->p4.z!=0 ){
sl@0	968	int i, j;
sl@0	969	char z[1000];
sl@0	970	sqlite3_snprintf(sizeof(z), z, "%s", pOp->p4.z);
sl@0	971	for(i=0; isspace((unsigned char)z[i]); i++){}
sl@0	972	for(j=0; z[i]; i++){
sl@0	973	if( isspace((unsigned char)z[i]) ){
sl@0	974	if( z[i-1]!=' ' ){
sl@0	975	z[j++] = ' ';
sl@0	976	}
sl@0	977	}else{
sl@0	978	z[j++] = z[i];
sl@0	979	}
sl@0	980	}
sl@0	981	z[j] = 0;
sl@0	982	sqlite3IoTrace("SQL %s\n", z);
sl@0	983	}
sl@0	984	}
sl@0	985	#endif /* !SQLITE_OMIT_TRACE && SQLITE_ENABLE_IOTRACE */
sl@0	986
sl@0	987
sl@0	988	/*
sl@0	989	** Prepare a virtual machine for execution. This involves things such
sl@0	990	** as allocating stack space and initializing the program counter.
sl@0	991	** After the VDBE has be prepped, it can be executed by one or more
sl@0	992	** calls to sqlite3VdbeExec().
sl@0	993	**
sl@0	994	** This is the only way to move a VDBE from VDBE_MAGIC_INIT to
sl@0	995	** VDBE_MAGIC_RUN.
sl@0	996	*/
sl@0	997	void sqlite3VdbeMakeReady(
sl@0	998	Vdbe p, / The VDBE */
sl@0	999	int nVar, /* Number of '?' see in the SQL statement */
sl@0	1000	int nMem, /* Number of memory cells to allocate */
sl@0	1001	int nCursor, /* Number of cursors to allocate */
sl@0	1002	int isExplain /* True if the EXPLAIN keywords is present */
sl@0	1003	){
sl@0	1004	int n;
sl@0	1005	sqlite3 *db = p->db;
sl@0	1006
sl@0	1007	assert( p!=0 );
sl@0	1008	assert( p->magic==VDBE_MAGIC_INIT );
sl@0	1009
sl@0	1010	/* There should be at least one opcode.
sl@0	1011	*/
sl@0	1012	assert( p->nOp>0 );
sl@0	1013
sl@0	1014	/* Set the magic to VDBE_MAGIC_RUN sooner rather than later. This
sl@0	1015	* is because the call to resizeOpArray() below may shrink the
sl@0	1016	* p->aOp[] array to save memory if called when in VDBE_MAGIC_RUN
sl@0	1017	* state.
sl@0	1018	*/
sl@0	1019	p->magic = VDBE_MAGIC_RUN;
sl@0	1020
sl@0	1021	/* For each cursor required, also allocate a memory cell. Memory
sl@0	1022	** cells (nMem+1-nCursor)..nMem, inclusive, will never be used by
sl@0	1023	** the vdbe program. Instead they are used to allocate space for
sl@0	1024	** Cursor/BtCursor structures. The blob of memory associated with
sl@0	1025	** cursor 0 is stored in memory cell nMem. Memory cell (nMem-1)
sl@0	1026	** stores the blob of memory associated with cursor 1, etc.
sl@0	1027	**
sl@0	1028	** See also: allocateCursor().
sl@0	1029	*/
sl@0	1030	nMem += nCursor;
sl@0	1031
sl@0	1032	/*
sl@0	1033	** Allocation space for registers.
sl@0	1034	*/
sl@0	1035	if( p->aMem==0 ){
sl@0	1036	int nArg; /* Maximum number of args passed to a user function. */
sl@0	1037	resolveP2Values(p, &nArg);
sl@0	1038	/resizeOpArray(p, p->nOp);/
sl@0	1039	assert( nVar>=0 );
sl@0	1040	if( isExplain && nMem<10 ){
sl@0	1041	p->nMem = nMem = 10;
sl@0	1042	}
sl@0	1043	p->aMem = sqlite3DbMallocZero(db,
sl@0	1044	nMemsizeof(Mem) / aMem */
sl@0	1045	+ nVarsizeof(Mem) / aVar */
sl@0	1046	+ nArgsizeof(Mem) /* apArg */
sl@0	1047	+ nVarsizeof(char) /* azVar */
sl@0	1048	+ nCursorsizeof(Cursor) + 1 /* apCsr */
sl@0	1049	);
sl@0	1050	if( !db->mallocFailed ){
sl@0	1051	p->aMem--; /* aMem[] goes from 1..nMem */
sl@0	1052	p->nMem = nMem; /* not from 0..nMem-1 */
sl@0	1053	p->aVar = &p->aMem[nMem+1];
sl@0	1054	p->nVar = nVar;
sl@0	1055	p->okVar = 0;
sl@0	1056	p->apArg = (Mem**)&p->aVar[nVar];
sl@0	1057	p->azVar = (char**)&p->apArg[nArg];
sl@0	1058	p->apCsr = (Cursor**)&p->azVar[nVar];
sl@0	1059	p->nCursor = nCursor;
sl@0	1060	for(n=0; n<nVar; n++){
sl@0	1061	p->aVar[n].flags = MEM_Null;
sl@0	1062	p->aVar[n].db = db;
sl@0	1063	}
sl@0	1064	for(n=1; n<=nMem; n++){
sl@0	1065	p->aMem[n].flags = MEM_Null;
sl@0	1066	p->aMem[n].db = db;
sl@0	1067	}
sl@0	1068	}
sl@0	1069	}
sl@0	1070	#ifdef SQLITE_DEBUG
sl@0	1071	for(n=1; n<p->nMem; n++){
sl@0	1072	assert( p->aMem[n].db==db );
sl@0	1073	}
sl@0	1074	#endif
sl@0	1075
sl@0	1076	p->pc = -1;
sl@0	1077	p->rc = SQLITE_OK;
sl@0	1078	p->uniqueCnt = 0;
sl@0	1079	p->errorAction = OE_Abort;
sl@0	1080	p->explain \|= isExplain;
sl@0	1081	p->magic = VDBE_MAGIC_RUN;
sl@0	1082	p->nChange = 0;
sl@0	1083	p->cacheCtr = 1;
sl@0	1084	p->minWriteFileFormat = 255;
sl@0	1085	p->openedStatement = 0;
sl@0	1086	#ifdef VDBE_PROFILE
sl@0	1087	{
sl@0	1088	int i;
sl@0	1089	for(i=0; i<p->nOp; i++){
sl@0	1090	p->aOp[i].cnt = 0;
sl@0	1091	p->aOp[i].cycles = 0;
sl@0	1092	}
sl@0	1093	}
sl@0	1094	#endif
sl@0	1095	}
sl@0	1096
sl@0	1097	/*
sl@0	1098	** Close a VDBE cursor and release all the resources that cursor
sl@0	1099	** happens to hold.
sl@0	1100	*/
sl@0	1101	void sqlite3VdbeFreeCursor(Vdbe p, Cursor pCx){
sl@0	1102	if( pCx==0 ){
sl@0	1103	return;
sl@0	1104	}
sl@0	1105	if( pCx->pBt ){
sl@0	1106	sqlite3BtreeClose(pCx->pBt);
sl@0	1107	/* The pCx->pCursor will be close automatically, if it exists, by
sl@0	1108	** the call above. */
sl@0	1109	}else if( pCx->pCursor ){
sl@0	1110	sqlite3BtreeCloseCursor(pCx->pCursor);
sl@0	1111	}
sl@0	1112	#ifndef SQLITE_OMIT_VIRTUALTABLE
sl@0	1113	if( pCx->pVtabCursor ){
sl@0	1114	sqlite3_vtab_cursor *pVtabCursor = pCx->pVtabCursor;
sl@0	1115	const sqlite3_module *pModule = pCx->pModule;
sl@0	1116	p->inVtabMethod = 1;
sl@0	1117	(void)sqlite3SafetyOff(p->db);
sl@0	1118	pModule->xClose(pVtabCursor);
sl@0	1119	(void)sqlite3SafetyOn(p->db);
sl@0	1120	p->inVtabMethod = 0;
sl@0	1121	}
sl@0	1122	#endif
sl@0	1123	if( !pCx->ephemPseudoTable ){
sl@0	1124	sqlite3DbFree(p->db, pCx->pData);
sl@0	1125	}
sl@0	1126	}
sl@0	1127
sl@0	1128	/*
sl@0	1129	** Close all cursors except for VTab cursors that are currently
sl@0	1130	** in use.
sl@0	1131	*/
sl@0	1132	static void closeAllCursorsExceptActiveVtabs(Vdbe *p){
sl@0	1133	int i;
sl@0	1134	if( p->apCsr==0 ) return;
sl@0	1135	for(i=0; i<p->nCursor; i++){
sl@0	1136	Cursor *pC = p->apCsr[i];
sl@0	1137	if( pC && (!p->inVtabMethod \|\| !pC->pVtabCursor) ){
sl@0	1138	sqlite3VdbeFreeCursor(p, pC);
sl@0	1139	p->apCsr[i] = 0;
sl@0	1140	}
sl@0	1141	}
sl@0	1142	}
sl@0	1143
sl@0	1144	/*
sl@0	1145	** Clean up the VM after execution.
sl@0	1146	**
sl@0	1147	** This routine will automatically close any cursors, lists, and/or
sl@0	1148	** sorters that were left open. It also deletes the values of
sl@0	1149	** variables in the aVar[] array.
sl@0	1150	*/
sl@0	1151	static void Cleanup(Vdbe *p){
sl@0	1152	int i;
sl@0	1153	sqlite3 *db = p->db;
sl@0	1154	closeAllCursorsExceptActiveVtabs(p);
sl@0	1155	for(i=1; i<=p->nMem; i++){
sl@0	1156	MemSetTypeFlag(&p->aMem[i], MEM_Null);
sl@0	1157	}
sl@0	1158	releaseMemArray(&p->aMem[1], p->nMem);
sl@0	1159	sqlite3VdbeFifoClear(&p->sFifo);
sl@0	1160	if( p->contextStack ){
sl@0	1161	for(i=0; i<p->contextStackTop; i++){
sl@0	1162	sqlite3VdbeFifoClear(&p->contextStack[i].sFifo);
sl@0	1163	}
sl@0	1164	sqlite3DbFree(db, p->contextStack);
sl@0	1165	}
sl@0	1166	p->contextStack = 0;
sl@0	1167	p->contextStackDepth = 0;
sl@0	1168	p->contextStackTop = 0;
sl@0	1169	sqlite3DbFree(db, p->zErrMsg);
sl@0	1170	p->zErrMsg = 0;
sl@0	1171	p->pResultSet = 0;
sl@0	1172	}
sl@0	1173
sl@0	1174	/*
sl@0	1175	** Set the number of result columns that will be returned by this SQL
sl@0	1176	** statement. This is now set at compile time, rather than during
sl@0	1177	** execution of the vdbe program so that sqlite3_column_count() can
sl@0	1178	** be called on an SQL statement before sqlite3_step().
sl@0	1179	*/
sl@0	1180	void sqlite3VdbeSetNumCols(Vdbe *p, int nResColumn){
sl@0	1181	Mem *pColName;
sl@0	1182	int n;
sl@0	1183	sqlite3 *db = p->db;
sl@0	1184
sl@0	1185	releaseMemArray(p->aColName, p->nResColumn*COLNAME_N);
sl@0	1186	sqlite3DbFree(db, p->aColName);
sl@0	1187	n = nResColumn*COLNAME_N;
sl@0	1188	p->nResColumn = nResColumn;
sl@0	1189	p->aColName = pColName = (Mem)sqlite3DbMallocZero(db, sizeof(Mem)n );
sl@0	1190	if( p->aColName==0 ) return;
sl@0	1191	while( n-- > 0 ){
sl@0	1192	pColName->flags = MEM_Null;
sl@0	1193	pColName->db = p->db;
sl@0	1194	pColName++;
sl@0	1195	}
sl@0	1196	}
sl@0	1197
sl@0	1198	/*
sl@0	1199	** Set the name of the idx'th column to be returned by the SQL statement.
sl@0	1200	** zName must be a pointer to a nul terminated string.
sl@0	1201	**
sl@0	1202	** This call must be made after a call to sqlite3VdbeSetNumCols().
sl@0	1203	**
sl@0	1204	** If N==P4_STATIC it means that zName is a pointer to a constant static
sl@0	1205	** string and we can just copy the pointer. If it is P4_DYNAMIC, then
sl@0	1206	** the string is freed using sqlite3DbFree(db, ) when the vdbe is finished with
sl@0	1207	** it. Otherwise, N bytes of zName are copied.
sl@0	1208	*/
sl@0	1209	int sqlite3VdbeSetColName(Vdbe p, int idx, int var, const char zName, int N){
sl@0	1210	int rc;
sl@0	1211	Mem *pColName;
sl@0	1212	assert( idx<p->nResColumn );
sl@0	1213	assert( var<COLNAME_N );
sl@0	1214	if( p->db->mallocFailed ) return SQLITE_NOMEM;
sl@0	1215	assert( p->aColName!=0 );
sl@0	1216	pColName = &(p->aColName[idx+var*p->nResColumn]);
sl@0	1217	if( N==P4_DYNAMIC \|\| N==P4_STATIC ){
sl@0	1218	rc = sqlite3VdbeMemSetStr(pColName, zName, -1, SQLITE_UTF8, SQLITE_STATIC);
sl@0	1219	}else{
sl@0	1220	rc = sqlite3VdbeMemSetStr(pColName, zName, N, SQLITE_UTF8,SQLITE_TRANSIENT);
sl@0	1221	}
sl@0	1222	if( rc==SQLITE_OK && N==P4_DYNAMIC ){
sl@0	1223	pColName->flags &= (~MEM_Static);
sl@0	1224	pColName->zMalloc = pColName->z;
sl@0	1225	}
sl@0	1226	return rc;
sl@0	1227	}
sl@0	1228
sl@0	1229	/*
sl@0	1230	** A read or write transaction may or may not be active on database handle
sl@0	1231	** db. If a transaction is active, commit it. If there is a
sl@0	1232	** write-transaction spanning more than one database file, this routine
sl@0	1233	** takes care of the master journal trickery.
sl@0	1234	*/
sl@0	1235	static int vdbeCommit(sqlite3 db, Vdbe p){
sl@0	1236	int i;
sl@0	1237	int nTrans = 0; /* Number of databases with an active write-transaction */
sl@0	1238	int rc = SQLITE_OK;
sl@0	1239	int needXcommit = 0;
sl@0	1240
sl@0	1241	/* Before doing anything else, call the xSync() callback for any
sl@0	1242	** virtual module tables written in this transaction. This has to
sl@0	1243	** be done before determining whether a master journal file is
sl@0	1244	** required, as an xSync() callback may add an attached database
sl@0	1245	** to the transaction.
sl@0	1246	*/
sl@0	1247	rc = sqlite3VtabSync(db, &p->zErrMsg);
sl@0	1248	if( rc!=SQLITE_OK ){
sl@0	1249	return rc;
sl@0	1250	}
sl@0	1251
sl@0	1252	/* This loop determines (a) if the commit hook should be invoked and
sl@0	1253	** (b) how many database files have open write transactions, not
sl@0	1254	** including the temp database. (b) is important because if more than
sl@0	1255	** one database file has an open write transaction, a master journal
sl@0	1256	** file is required for an atomic commit.
sl@0	1257	*/
sl@0	1258	for(i=0; i<db->nDb; i++){
sl@0	1259	Btree *pBt = db->aDb[i].pBt;
sl@0	1260	if( sqlite3BtreeIsInTrans(pBt) ){
sl@0	1261	needXcommit = 1;
sl@0	1262	if( i!=1 ) nTrans++;
sl@0	1263	}
sl@0	1264	}
sl@0	1265
sl@0	1266	/* If there are any write-transactions at all, invoke the commit hook */
sl@0	1267	if( needXcommit && db->xCommitCallback ){
sl@0	1268	(void)sqlite3SafetyOff(db);
sl@0	1269	rc = db->xCommitCallback(db->pCommitArg);
sl@0	1270	(void)sqlite3SafetyOn(db);
sl@0	1271	if( rc ){
sl@0	1272	return SQLITE_CONSTRAINT;
sl@0	1273	}
sl@0	1274	}
sl@0	1275
sl@0	1276	/* The simple case - no more than one database file (not counting the
sl@0	1277	** TEMP database) has a transaction active. There is no need for the
sl@0	1278	** master-journal.
sl@0	1279	**
sl@0	1280	** If the return value of sqlite3BtreeGetFilename() is a zero length
sl@0	1281	** string, it means the main database is :memory: or a temp file. In
sl@0	1282	** that case we do not support atomic multi-file commits, so use the
sl@0	1283	** simple case then too.
sl@0	1284	*/
sl@0	1285	if( 0==strlen(sqlite3BtreeGetFilename(db->aDb[0].pBt)) \|\| nTrans<=1 ){
sl@0	1286	for(i=0; rc==SQLITE_OK && i<db->nDb; i++){
sl@0	1287	Btree *pBt = db->aDb[i].pBt;
sl@0	1288	if( pBt ){
sl@0	1289	rc = sqlite3BtreeCommitPhaseOne(pBt, 0);
sl@0	1290	}
sl@0	1291	}
sl@0	1292
sl@0	1293	/* Do the commit only if all databases successfully complete phase 1.
sl@0	1294	** If one of the BtreeCommitPhaseOne() calls fails, this indicates an
sl@0	1295	** IO error while deleting or truncating a journal file. It is unlikely,
sl@0	1296	** but could happen. In this case abandon processing and return the error.
sl@0	1297	*/
sl@0	1298	for(i=0; rc==SQLITE_OK && i<db->nDb; i++){
sl@0	1299	Btree *pBt = db->aDb[i].pBt;
sl@0	1300	if( pBt ){
sl@0	1301	rc = sqlite3BtreeCommitPhaseTwo(pBt);
sl@0	1302	}
sl@0	1303	}
sl@0	1304	if( rc==SQLITE_OK ){
sl@0	1305	sqlite3VtabCommit(db);
sl@0	1306	}
sl@0	1307	}
sl@0	1308
sl@0	1309	/* The complex case - There is a multi-file write-transaction active.
sl@0	1310	** This requires a master journal file to ensure the transaction is
sl@0	1311	** committed atomicly.
sl@0	1312	*/
sl@0	1313	#ifndef SQLITE_OMIT_DISKIO
sl@0	1314	else{
sl@0	1315	sqlite3_vfs *pVfs = db->pVfs;
sl@0	1316	int needSync = 0;
sl@0	1317	char zMaster = 0; / File-name for the master journal */
sl@0	1318	char const *zMainFile = sqlite3BtreeGetFilename(db->aDb[0].pBt);
sl@0	1319	sqlite3_file *pMaster = 0;
sl@0	1320	i64 offset = 0;
sl@0	1321	int res;
sl@0	1322
sl@0	1323	/* Select a master journal file name */
sl@0	1324	do {
sl@0	1325	u32 random;
sl@0	1326	sqlite3DbFree(db, zMaster);
sl@0	1327	sqlite3_randomness(sizeof(random), &random);
sl@0	1328	zMaster = sqlite3MPrintf(db, "%s-mj%08X", zMainFile, random&0x7fffffff);
sl@0	1329	if( !zMaster ){
sl@0	1330	return SQLITE_NOMEM;
sl@0	1331	}
sl@0	1332	rc = sqlite3OsAccess(pVfs, zMaster, SQLITE_ACCESS_EXISTS, &res);
sl@0	1333	}while( rc==SQLITE_OK && res );
sl@0	1334	if( rc==SQLITE_OK ){
sl@0	1335	/* Open the master journal. */
sl@0	1336	rc = sqlite3OsOpenMalloc(pVfs, zMaster, &pMaster,
sl@0	1337	SQLITE_OPEN_READWRITE\|SQLITE_OPEN_CREATE\|
sl@0	1338	SQLITE_OPEN_EXCLUSIVE\|SQLITE_OPEN_MASTER_JOURNAL, 0
sl@0	1339	);
sl@0	1340	}
sl@0	1341	if( rc!=SQLITE_OK ){
sl@0	1342	sqlite3DbFree(db, zMaster);
sl@0	1343	return rc;
sl@0	1344	}
sl@0	1345
sl@0	1346	/* Write the name of each database file in the transaction into the new
sl@0	1347	** master journal file. If an error occurs at this point close
sl@0	1348	** and delete the master journal file. All the individual journal files
sl@0	1349	** still have 'null' as the master journal pointer, so they will roll
sl@0	1350	** back independently if a failure occurs.
sl@0	1351	*/
sl@0	1352	for(i=0; i<db->nDb; i++){
sl@0	1353	Btree *pBt = db->aDb[i].pBt;
sl@0	1354	if( i==1 ) continue; /* Ignore the TEMP database */
sl@0	1355	if( sqlite3BtreeIsInTrans(pBt) ){
sl@0	1356	char const *zFile = sqlite3BtreeGetJournalname(pBt);
sl@0	1357	if( zFile[0]==0 ) continue; /* Ignore :memory: databases */
sl@0	1358	if( !needSync && !sqlite3BtreeSyncDisabled(pBt) ){
sl@0	1359	needSync = 1;
sl@0	1360	}
sl@0	1361	rc = sqlite3OsWrite(pMaster, zFile, strlen(zFile)+1, offset);
sl@0	1362	offset += strlen(zFile)+1;
sl@0	1363	if( rc!=SQLITE_OK ){
sl@0	1364	sqlite3OsCloseFree(pMaster);
sl@0	1365	sqlite3OsDelete(pVfs, zMaster, 0);
sl@0	1366	sqlite3DbFree(db, zMaster);
sl@0	1367	return rc;
sl@0	1368	}
sl@0	1369	}
sl@0	1370	}
sl@0	1371
sl@0	1372	/* Sync the master journal file. If the IOCAP_SEQUENTIAL device
sl@0	1373	** flag is set this is not required.
sl@0	1374	*/
sl@0	1375	zMainFile = sqlite3BtreeGetDirname(db->aDb[0].pBt);
sl@0	1376	if( (needSync
sl@0	1377	&& (0==(sqlite3OsDeviceCharacteristics(pMaster)&SQLITE_IOCAP_SEQUENTIAL))
sl@0	1378	&& (rc=sqlite3OsSync(pMaster, SQLITE_SYNC_NORMAL))!=SQLITE_OK) ){
sl@0	1379	sqlite3OsCloseFree(pMaster);
sl@0	1380	sqlite3OsDelete(pVfs, zMaster, 0);
sl@0	1381	sqlite3DbFree(db, zMaster);
sl@0	1382	return rc;
sl@0	1383	}
sl@0	1384
sl@0	1385	/* Sync all the db files involved in the transaction. The same call
sl@0	1386	** sets the master journal pointer in each individual journal. If
sl@0	1387	** an error occurs here, do not delete the master journal file.
sl@0	1388	**
sl@0	1389	** If the error occurs during the first call to
sl@0	1390	** sqlite3BtreeCommitPhaseOne(), then there is a chance that the
sl@0	1391	** master journal file will be orphaned. But we cannot delete it,
sl@0	1392	** in case the master journal file name was written into the journal
sl@0	1393	** file before the failure occured.
sl@0	1394	*/
sl@0	1395	for(i=0; rc==SQLITE_OK && i<db->nDb; i++){
sl@0	1396	Btree *pBt = db->aDb[i].pBt;
sl@0	1397	if( pBt ){
sl@0	1398	rc = sqlite3BtreeCommitPhaseOne(pBt, zMaster);
sl@0	1399	}
sl@0	1400	}
sl@0	1401	sqlite3OsCloseFree(pMaster);
sl@0	1402	if( rc!=SQLITE_OK ){
sl@0	1403	sqlite3DbFree(db, zMaster);
sl@0	1404	return rc;
sl@0	1405	}
sl@0	1406
sl@0	1407	/* Delete the master journal file. This commits the transaction. After
sl@0	1408	** doing this the directory is synced again before any individual
sl@0	1409	** transaction files are deleted.
sl@0	1410	*/
sl@0	1411	rc = sqlite3OsDelete(pVfs, zMaster, 1);
sl@0	1412	sqlite3DbFree(db, zMaster);
sl@0	1413	zMaster = 0;
sl@0	1414	if( rc ){
sl@0	1415	return rc;
sl@0	1416	}
sl@0	1417
sl@0	1418	/* All files and directories have already been synced, so the following
sl@0	1419	** calls to sqlite3BtreeCommitPhaseTwo() are only closing files and
sl@0	1420	** deleting or truncating journals. If something goes wrong while
sl@0	1421	** this is happening we don't really care. The integrity of the
sl@0	1422	** transaction is already guaranteed, but some stray 'cold' journals
sl@0	1423	** may be lying around. Returning an error code won't help matters.
sl@0	1424	*/
sl@0	1425	disable_simulated_io_errors();
sl@0	1426	sqlite3BeginBenignMalloc();
sl@0	1427	for(i=0; i<db->nDb; i++){
sl@0	1428	Btree *pBt = db->aDb[i].pBt;
sl@0	1429	if( pBt ){
sl@0	1430	sqlite3BtreeCommitPhaseTwo(pBt);
sl@0	1431	}
sl@0	1432	}
sl@0	1433	sqlite3EndBenignMalloc();
sl@0	1434	enable_simulated_io_errors();
sl@0	1435
sl@0	1436	sqlite3VtabCommit(db);
sl@0	1437	}
sl@0	1438	#endif
sl@0	1439
sl@0	1440	return rc;
sl@0	1441	}
sl@0	1442
sl@0	1443	/*
sl@0	1444	** This routine checks that the sqlite3.activeVdbeCnt count variable
sl@0	1445	** matches the number of vdbe's in the list sqlite3.pVdbe that are
sl@0	1446	** currently active. An assertion fails if the two counts do not match.
sl@0	1447	** This is an internal self-check only - it is not an essential processing
sl@0	1448	** step.
sl@0	1449	**
sl@0	1450	** This is a no-op if NDEBUG is defined.
sl@0	1451	*/
sl@0	1452	#ifndef NDEBUG
sl@0	1453	static void checkActiveVdbeCnt(sqlite3 *db){
sl@0	1454	Vdbe *p;
sl@0	1455	int cnt = 0;
sl@0	1456	p = db->pVdbe;
sl@0	1457	while( p ){
sl@0	1458	if( p->magic==VDBE_MAGIC_RUN && p->pc>=0 ){
sl@0	1459	cnt++;
sl@0	1460	}
sl@0	1461	p = p->pNext;
sl@0	1462	}
sl@0	1463	assert( cnt==db->activeVdbeCnt );
sl@0	1464	}
sl@0	1465	#else
sl@0	1466	#define checkActiveVdbeCnt(x)
sl@0	1467	#endif
sl@0	1468
sl@0	1469	/*
sl@0	1470	** For every Btree that in database connection db which
sl@0	1471	** has been modified, "trip" or invalidate each cursor in
sl@0	1472	** that Btree might have been modified so that the cursor
sl@0	1473	** can never be used again. This happens when a rollback
sl@0	1474	*** occurs. We have to trip all the other cursors, even
sl@0	1475	** cursor from other VMs in different database connections,
sl@0	1476	** so that none of them try to use the data at which they
sl@0	1477	** were pointing and which now may have been changed due
sl@0	1478	** to the rollback.
sl@0	1479	**
sl@0	1480	** Remember that a rollback can delete tables complete and
sl@0	1481	** reorder rootpages. So it is not sufficient just to save
sl@0	1482	** the state of the cursor. We have to invalidate the cursor
sl@0	1483	** so that it is never used again.
sl@0	1484	*/
sl@0	1485	static void invalidateCursorsOnModifiedBtrees(sqlite3 *db){
sl@0	1486	int i;
sl@0	1487	for(i=0; i<db->nDb; i++){
sl@0	1488	Btree *p = db->aDb[i].pBt;
sl@0	1489	if( p && sqlite3BtreeIsInTrans(p) ){
sl@0	1490	sqlite3BtreeTripAllCursors(p, SQLITE_ABORT);
sl@0	1491	}
sl@0	1492	}
sl@0	1493	}
sl@0	1494
sl@0	1495	/*
sl@0	1496	** This routine is called the when a VDBE tries to halt. If the VDBE
sl@0	1497	** has made changes and is in autocommit mode, then commit those
sl@0	1498	** changes. If a rollback is needed, then do the rollback.
sl@0	1499	**
sl@0	1500	** This routine is the only way to move the state of a VM from
sl@0	1501	** SQLITE_MAGIC_RUN to SQLITE_MAGIC_HALT. It is harmless to
sl@0	1502	** call this on a VM that is in the SQLITE_MAGIC_HALT state.
sl@0	1503	**
sl@0	1504	** Return an error code. If the commit could not complete because of
sl@0	1505	** lock contention, return SQLITE_BUSY. If SQLITE_BUSY is returned, it
sl@0	1506	** means the close did not happen and needs to be repeated.
sl@0	1507	*/
sl@0	1508	int sqlite3VdbeHalt(Vdbe *p){
sl@0	1509	sqlite3 *db = p->db;
sl@0	1510	int i;
sl@0	1511	int (xFunc)(Btree pBt) = 0; /* Function to call on each btree backend */
sl@0	1512	int isSpecialError; /* Set to true if SQLITE_NOMEM or IOERR */
sl@0	1513
sl@0	1514	/* This function contains the logic that determines if a statement or
sl@0	1515	** transaction will be committed or rolled back as a result of the
sl@0	1516	** execution of this virtual machine.
sl@0	1517	**
sl@0	1518	** If any of the following errors occur:
sl@0	1519	**
sl@0	1520	** SQLITE_NOMEM
sl@0	1521	** SQLITE_IOERR
sl@0	1522	** SQLITE_FULL
sl@0	1523	** SQLITE_INTERRUPT
sl@0	1524	**
sl@0	1525	** Then the internal cache might have been left in an inconsistent
sl@0	1526	** state. We need to rollback the statement transaction, if there is
sl@0	1527	** one, or the complete transaction if there is no statement transaction.
sl@0	1528	*/
sl@0	1529
sl@0	1530	if( p->db->mallocFailed ){
sl@0	1531	p->rc = SQLITE_NOMEM;
sl@0	1532	}
sl@0	1533	closeAllCursorsExceptActiveVtabs(p);
sl@0	1534	if( p->magic!=VDBE_MAGIC_RUN ){
sl@0	1535	return SQLITE_OK;
sl@0	1536	}
sl@0	1537	checkActiveVdbeCnt(db);
sl@0	1538
sl@0	1539	/* No commit or rollback needed if the program never started */
sl@0	1540	if( p->pc>=0 ){
sl@0	1541	int mrc; /* Primary error code from p->rc */
sl@0	1542
sl@0	1543	/* Lock all btrees used by the statement */
sl@0	1544	sqlite3BtreeMutexArrayEnter(&p->aMutex);
sl@0	1545
sl@0	1546	/* Check for one of the special errors */
sl@0	1547	mrc = p->rc & 0xff;
sl@0	1548	isSpecialError = mrc==SQLITE_NOMEM \|\| mrc==SQLITE_IOERR
sl@0	1549	\|\| mrc==SQLITE_INTERRUPT \|\| mrc==SQLITE_FULL;
sl@0	1550	if( isSpecialError ){
sl@0	1551	/* This loop does static analysis of the query to see which of the
sl@0	1552	** following three categories it falls into:
sl@0	1553	**
sl@0	1554	** Read-only
sl@0	1555	** Query with statement journal
sl@0	1556	** Query without statement journal
sl@0	1557	**
sl@0	1558	** We could do something more elegant than this static analysis (i.e.
sl@0	1559	** store the type of query as part of the compliation phase), but
sl@0	1560	** handling malloc() or IO failure is a fairly obscure edge case so
sl@0	1561	** this is probably easier. Todo: Might be an opportunity to reduce
sl@0	1562	** code size a very small amount though...
sl@0	1563	*/
sl@0	1564	int notReadOnly = 0;
sl@0	1565	int isStatement = 0;
sl@0	1566	assert(p->aOp \|\| p->nOp==0);
sl@0	1567	for(i=0; i<p->nOp; i++){
sl@0	1568	switch( p->aOp[i].opcode ){
sl@0	1569	case OP_Transaction:
sl@0	1570	notReadOnly \|= p->aOp[i].p2;
sl@0	1571	break;
sl@0	1572	case OP_Statement:
sl@0	1573	isStatement = 1;
sl@0	1574	break;
sl@0	1575	}
sl@0	1576	}
sl@0	1577
sl@0	1578
sl@0	1579	/* If the query was read-only, we need do no rollback at all. Otherwise,
sl@0	1580	** proceed with the special handling.
sl@0	1581	*/
sl@0	1582	if( notReadOnly \|\| mrc!=SQLITE_INTERRUPT ){
sl@0	1583	if( p->rc==SQLITE_IOERR_BLOCKED && isStatement ){
sl@0	1584	xFunc = sqlite3BtreeRollbackStmt;
sl@0	1585	p->rc = SQLITE_BUSY;
sl@0	1586	} else if( (mrc==SQLITE_NOMEM \|\| mrc==SQLITE_FULL) && isStatement ){
sl@0	1587	xFunc = sqlite3BtreeRollbackStmt;
sl@0	1588	}else{
sl@0	1589	/* We are forced to roll back the active transaction. Before doing
sl@0	1590	** so, abort any other statements this handle currently has active.
sl@0	1591	*/
sl@0	1592	invalidateCursorsOnModifiedBtrees(db);
sl@0	1593	sqlite3RollbackAll(db);
sl@0	1594	db->autoCommit = 1;
sl@0	1595	}
sl@0	1596	}
sl@0	1597	}
sl@0	1598
sl@0	1599	/* If the auto-commit flag is set and this is the only active vdbe, then
sl@0	1600	** we do either a commit or rollback of the current transaction.
sl@0	1601	**
sl@0	1602	** Note: This block also runs if one of the special errors handled
sl@0	1603	** above has occured.
sl@0	1604	*/
sl@0	1605	if( db->autoCommit && db->activeVdbeCnt==1 ){
sl@0	1606	if( p->rc==SQLITE_OK \|\| (p->errorAction==OE_Fail && !isSpecialError) ){
sl@0	1607	/* The auto-commit flag is true, and the vdbe program was
sl@0	1608	** successful or hit an 'OR FAIL' constraint. This means a commit
sl@0	1609	** is required.
sl@0	1610	*/
sl@0	1611	int rc = vdbeCommit(db, p);
sl@0	1612	if( rc==SQLITE_BUSY ){
sl@0	1613	sqlite3BtreeMutexArrayLeave(&p->aMutex);
sl@0	1614	return SQLITE_BUSY;
sl@0	1615	}else if( rc!=SQLITE_OK ){
sl@0	1616	p->rc = rc;
sl@0	1617	sqlite3RollbackAll(db);
sl@0	1618	}else{
sl@0	1619	sqlite3CommitInternalChanges(db);
sl@0	1620	}
sl@0	1621	}else{
sl@0	1622	sqlite3RollbackAll(db);
sl@0	1623	}
sl@0	1624	}else if( !xFunc ){
sl@0	1625	if( p->rc==SQLITE_OK \|\| p->errorAction==OE_Fail ){
sl@0	1626	if( p->openedStatement ){
sl@0	1627	xFunc = sqlite3BtreeCommitStmt;
sl@0	1628	}
sl@0	1629	}else if( p->errorAction==OE_Abort ){
sl@0	1630	xFunc = sqlite3BtreeRollbackStmt;
sl@0	1631	}else{
sl@0	1632	invalidateCursorsOnModifiedBtrees(db);
sl@0	1633	sqlite3RollbackAll(db);
sl@0	1634	db->autoCommit = 1;
sl@0	1635	}
sl@0	1636	}
sl@0	1637
sl@0	1638	/* If xFunc is not NULL, then it is one of sqlite3BtreeRollbackStmt or
sl@0	1639	** sqlite3BtreeCommitStmt. Call it once on each backend. If an error occurs
sl@0	1640	** and the return code is still SQLITE_OK, set the return code to the new
sl@0	1641	** error value.
sl@0	1642	*/
sl@0	1643	assert(!xFunc \|\|
sl@0	1644	xFunc==sqlite3BtreeCommitStmt \|\|
sl@0	1645	xFunc==sqlite3BtreeRollbackStmt
sl@0	1646	);
sl@0	1647	for(i=0; xFunc && i<db->nDb; i++){
sl@0	1648	int rc;
sl@0	1649	Btree *pBt = db->aDb[i].pBt;
sl@0	1650	if( pBt ){
sl@0	1651	rc = xFunc(pBt);
sl@0	1652	if( rc && (p->rc==SQLITE_OK \|\| p->rc==SQLITE_CONSTRAINT) ){
sl@0	1653	p->rc = rc;
sl@0	1654	sqlite3DbFree(db, p->zErrMsg);
sl@0	1655	p->zErrMsg = 0;
sl@0	1656	}
sl@0	1657	}
sl@0	1658	}
sl@0	1659
sl@0	1660	/* If this was an INSERT, UPDATE or DELETE and the statement was committed,
sl@0	1661	** set the change counter.
sl@0	1662	*/
sl@0	1663	if( p->changeCntOn && p->pc>=0 ){
sl@0	1664	if( !xFunc \|\| xFunc==sqlite3BtreeCommitStmt ){
sl@0	1665	sqlite3VdbeSetChanges(db, p->nChange);
sl@0	1666	}else{
sl@0	1667	sqlite3VdbeSetChanges(db, 0);
sl@0	1668	}
sl@0	1669	p->nChange = 0;
sl@0	1670	}
sl@0	1671
sl@0	1672	/* Rollback or commit any schema changes that occurred. */
sl@0	1673	if( p->rc!=SQLITE_OK && db->flags&SQLITE_InternChanges ){
sl@0	1674	sqlite3ResetInternalSchema(db, 0);
sl@0	1675	db->flags = (db->flags \| SQLITE_InternChanges);
sl@0	1676	}
sl@0	1677
sl@0	1678	/* Release the locks */
sl@0	1679	sqlite3BtreeMutexArrayLeave(&p->aMutex);
sl@0	1680	}
sl@0	1681
sl@0	1682	/* We have successfully halted and closed the VM. Record this fact. */
sl@0	1683	if( p->pc>=0 ){
sl@0	1684	db->activeVdbeCnt--;
sl@0	1685	}
sl@0	1686	p->magic = VDBE_MAGIC_HALT;
sl@0	1687	checkActiveVdbeCnt(db);
sl@0	1688	if( p->db->mallocFailed ){
sl@0	1689	p->rc = SQLITE_NOMEM;
sl@0	1690	}
sl@0	1691
sl@0	1692	return SQLITE_OK;
sl@0	1693	}
sl@0	1694
sl@0	1695
sl@0	1696	/*
sl@0	1697	** Each VDBE holds the result of the most recent sqlite3_step() call
sl@0	1698	** in p->rc. This routine sets that result back to SQLITE_OK.
sl@0	1699	*/
sl@0	1700	void sqlite3VdbeResetStepResult(Vdbe *p){
sl@0	1701	p->rc = SQLITE_OK;
sl@0	1702	}
sl@0	1703
sl@0	1704	/*
sl@0	1705	** Clean up a VDBE after execution but do not delete the VDBE just yet.
sl@0	1706	** Write any error messages into *pzErrMsg. Return the result code.
sl@0	1707	**
sl@0	1708	** After this routine is run, the VDBE should be ready to be executed
sl@0	1709	** again.
sl@0	1710	**
sl@0	1711	** To look at it another way, this routine resets the state of the
sl@0	1712	** virtual machine from VDBE_MAGIC_RUN or VDBE_MAGIC_HALT back to
sl@0	1713	** VDBE_MAGIC_INIT.
sl@0	1714	*/
sl@0	1715	int sqlite3VdbeReset(Vdbe *p){
sl@0	1716	sqlite3 *db;
sl@0	1717	db = p->db;
sl@0	1718
sl@0	1719	/* If the VM did not run to completion or if it encountered an
sl@0	1720	** error, then it might not have been halted properly. So halt
sl@0	1721	** it now.
sl@0	1722	*/
sl@0	1723	(void)sqlite3SafetyOn(db);
sl@0	1724	sqlite3VdbeHalt(p);
sl@0	1725	(void)sqlite3SafetyOff(db);
sl@0	1726
sl@0	1727	/* If the VDBE has be run even partially, then transfer the error code
sl@0	1728	** and error message from the VDBE into the main database structure. But
sl@0	1729	** if the VDBE has just been set to run but has not actually executed any
sl@0	1730	** instructions yet, leave the main database error information unchanged.
sl@0	1731	*/
sl@0	1732	if( p->pc>=0 ){
sl@0	1733	if( p->zErrMsg ){
sl@0	1734	sqlite3BeginBenignMalloc();
sl@0	1735	sqlite3ValueSetStr(db->pErr,-1,p->zErrMsg,SQLITE_UTF8,SQLITE_TRANSIENT);
sl@0	1736	sqlite3EndBenignMalloc();
sl@0	1737	db->errCode = p->rc;
sl@0	1738	sqlite3DbFree(db, p->zErrMsg);
sl@0	1739	p->zErrMsg = 0;
sl@0	1740	}else if( p->rc ){
sl@0	1741	sqlite3Error(db, p->rc, 0);
sl@0	1742	}else{
sl@0	1743	sqlite3Error(db, SQLITE_OK, 0);
sl@0	1744	}
sl@0	1745	}else if( p->rc && p->expired ){
sl@0	1746	/* The expired flag was set on the VDBE before the first call
sl@0	1747	** to sqlite3_step(). For consistency (since sqlite3_step() was
sl@0	1748	** called), set the database error in this case as well.
sl@0	1749	*/
sl@0	1750	sqlite3Error(db, p->rc, 0);
sl@0	1751	sqlite3ValueSetStr(db->pErr, -1, p->zErrMsg, SQLITE_UTF8, SQLITE_TRANSIENT);
sl@0	1752	sqlite3DbFree(db, p->zErrMsg);
sl@0	1753	p->zErrMsg = 0;
sl@0	1754	}
sl@0	1755
sl@0	1756	/* Reclaim all memory used by the VDBE
sl@0	1757	*/
sl@0	1758	Cleanup(p);
sl@0	1759
sl@0	1760	/* Save profiling information from this VDBE run.
sl@0	1761	*/
sl@0	1762	#ifdef VDBE_PROFILE
sl@0	1763	{
sl@0	1764	FILE *out = fopen("vdbe_profile.out", "a");
sl@0	1765	if( out ){
sl@0	1766	int i;
sl@0	1767	fprintf(out, "---- ");
sl@0	1768	for(i=0; i<p->nOp; i++){
sl@0	1769	fprintf(out, "%02x", p->aOp[i].opcode);
sl@0	1770	}
sl@0	1771	fprintf(out, "\n");
sl@0	1772	for(i=0; i<p->nOp; i++){
sl@0	1773	fprintf(out, "%6d %10lld %8lld ",
sl@0	1774	p->aOp[i].cnt,
sl@0	1775	p->aOp[i].cycles,
sl@0	1776	p->aOp[i].cnt>0 ? p->aOp[i].cycles/p->aOp[i].cnt : 0
sl@0	1777	);
sl@0	1778	sqlite3VdbePrintOp(out, i, &p->aOp[i]);
sl@0	1779	}
sl@0	1780	fclose(out);
sl@0	1781	}
sl@0	1782	}
sl@0	1783	#endif
sl@0	1784	p->magic = VDBE_MAGIC_INIT;
sl@0	1785	return p->rc & db->errMask;
sl@0	1786	}
sl@0	1787
sl@0	1788	/*
sl@0	1789	** Clean up and delete a VDBE after execution. Return an integer which is
sl@0	1790	** the result code. Write any error message text into *pzErrMsg.
sl@0	1791	*/
sl@0	1792	int sqlite3VdbeFinalize(Vdbe *p){
sl@0	1793	int rc = SQLITE_OK;
sl@0	1794	if( p->magic==VDBE_MAGIC_RUN \|\| p->magic==VDBE_MAGIC_HALT ){
sl@0	1795	rc = sqlite3VdbeReset(p);
sl@0	1796	assert( (rc & p->db->errMask)==rc );
sl@0	1797	}else if( p->magic!=VDBE_MAGIC_INIT ){
sl@0	1798	return SQLITE_MISUSE;
sl@0	1799	}
sl@0	1800	sqlite3VdbeDelete(p);
sl@0	1801	return rc;
sl@0	1802	}
sl@0	1803
sl@0	1804	/*
sl@0	1805	** Call the destructor for each auxdata entry in pVdbeFunc for which
sl@0	1806	** the corresponding bit in mask is clear. Auxdata entries beyond 31
sl@0	1807	** are always destroyed. To destroy all auxdata entries, call this
sl@0	1808	** routine with mask==0.
sl@0	1809	*/
sl@0	1810	void sqlite3VdbeDeleteAuxData(VdbeFunc *pVdbeFunc, int mask){
sl@0	1811	int i;
sl@0	1812	for(i=0; i<pVdbeFunc->nAux; i++){
sl@0	1813	struct AuxData *pAux = &pVdbeFunc->apAux[i];
sl@0	1814	if( (i>31 \|\| !(mask&(1<<i))) && pAux->pAux ){
sl@0	1815	if( pAux->xDelete ){
sl@0	1816	pAux->xDelete(pAux->pAux);
sl@0	1817	}
sl@0	1818	pAux->pAux = 0;
sl@0	1819	}
sl@0	1820	}
sl@0	1821	}
sl@0	1822
sl@0	1823	/*
sl@0	1824	** Delete an entire VDBE.
sl@0	1825	*/
sl@0	1826	void sqlite3VdbeDelete(Vdbe *p){
sl@0	1827	int i;
sl@0	1828	sqlite3 *db;
sl@0	1829
sl@0	1830	if( p==0 ) return;
sl@0	1831	db = p->db;
sl@0	1832	if( p->pPrev ){
sl@0	1833	p->pPrev->pNext = p->pNext;
sl@0	1834	}else{
sl@0	1835	assert( db->pVdbe==p );
sl@0	1836	db->pVdbe = p->pNext;
sl@0	1837	}
sl@0	1838	if( p->pNext ){
sl@0	1839	p->pNext->pPrev = p->pPrev;
sl@0	1840	}
sl@0	1841	if( p->aOp ){
sl@0	1842	Op *pOp = p->aOp;
sl@0	1843	for(i=0; i<p->nOp; i++, pOp++){
sl@0	1844	freeP4(db, pOp->p4type, pOp->p4.p);
sl@0	1845	#ifdef SQLITE_DEBUG
sl@0	1846	sqlite3DbFree(db, pOp->zComment);
sl@0	1847	#endif
sl@0	1848	}
sl@0	1849	sqlite3DbFree(db, p->aOp);
sl@0	1850	}
sl@0	1851	releaseMemArray(p->aVar, p->nVar);
sl@0	1852	sqlite3DbFree(db, p->aLabel);
sl@0	1853	if( p->aMem ){
sl@0	1854	sqlite3DbFree(db, &p->aMem[1]);
sl@0	1855	}
sl@0	1856	releaseMemArray(p->aColName, p->nResColumn*COLNAME_N);
sl@0	1857	sqlite3DbFree(db, p->aColName);
sl@0	1858	sqlite3DbFree(db, p->zSql);
sl@0	1859	p->magic = VDBE_MAGIC_DEAD;
sl@0	1860	sqlite3DbFree(db, p);
sl@0	1861	}
sl@0	1862
sl@0	1863	/*
sl@0	1864	** If a MoveTo operation is pending on the given cursor, then do that
sl@0	1865	** MoveTo now. Return an error code. If no MoveTo is pending, this
sl@0	1866	** routine does nothing and returns SQLITE_OK.
sl@0	1867	*/
sl@0	1868	int sqlite3VdbeCursorMoveto(Cursor *p){
sl@0	1869	if( p->deferredMoveto ){
sl@0	1870	int res, rc;
sl@0	1871	#ifdef SQLITE_TEST
sl@0	1872	extern int sqlite3_search_count;
sl@0	1873	#endif
sl@0	1874	assert( p->isTable );
sl@0	1875	rc = sqlite3BtreeMovetoUnpacked(p->pCursor, 0, p->movetoTarget, 0, &res);
sl@0	1876	if( rc ) return rc;
sl@0	1877	p->lastRowid = keyToInt(p->movetoTarget);
sl@0	1878	p->rowidIsValid = res==0;
sl@0	1879	if( res<0 ){
sl@0	1880	rc = sqlite3BtreeNext(p->pCursor, &res);
sl@0	1881	if( rc ) return rc;
sl@0	1882	}
sl@0	1883	#ifdef SQLITE_TEST
sl@0	1884	sqlite3_search_count++;
sl@0	1885	#endif
sl@0	1886	p->deferredMoveto = 0;
sl@0	1887	p->cacheStatus = CACHE_STALE;
sl@0	1888	}else if( p->pCursor ){
sl@0	1889	int hasMoved;
sl@0	1890	int rc = sqlite3BtreeCursorHasMoved(p->pCursor, &hasMoved);
sl@0	1891	if( rc ) return rc;
sl@0	1892	if( hasMoved ){
sl@0	1893	p->cacheStatus = CACHE_STALE;
sl@0	1894	p->nullRow = 1;
sl@0	1895	}
sl@0	1896	}
sl@0	1897	return SQLITE_OK;
sl@0	1898	}
sl@0	1899
sl@0	1900	/*
sl@0	1901	** The following functions:
sl@0	1902	**
sl@0	1903	** sqlite3VdbeSerialType()
sl@0	1904	** sqlite3VdbeSerialTypeLen()
sl@0	1905	** sqlite3VdbeSerialLen()
sl@0	1906	** sqlite3VdbeSerialPut()
sl@0	1907	** sqlite3VdbeSerialGet()
sl@0	1908	**
sl@0	1909	** encapsulate the code that serializes values for storage in SQLite
sl@0	1910	** data and index records. Each serialized value consists of a
sl@0	1911	** 'serial-type' and a blob of data. The serial type is an 8-byte unsigned
sl@0	1912	** integer, stored as a varint.
sl@0	1913	**
sl@0	1914	** In an SQLite index record, the serial type is stored directly before
sl@0	1915	** the blob of data that it corresponds to. In a table record, all serial
sl@0	1916	** types are stored at the start of the record, and the blobs of data at
sl@0	1917	** the end. Hence these functions allow the caller to handle the
sl@0	1918	** serial-type and data blob seperately.
sl@0	1919	**
sl@0	1920	** The following table describes the various storage classes for data:
sl@0	1921	**
sl@0	1922	** serial type bytes of data type
sl@0	1923	** -------------- --------------- ---------------
sl@0	1924	** 0 0 NULL
sl@0	1925	** 1 1 signed integer
sl@0	1926	** 2 2 signed integer
sl@0	1927	** 3 3 signed integer
sl@0	1928	** 4 4 signed integer
sl@0	1929	** 5 6 signed integer
sl@0	1930	** 6 8 signed integer
sl@0	1931	** 7 8 IEEE float
sl@0	1932	** 8 0 Integer constant 0
sl@0	1933	** 9 0 Integer constant 1
sl@0	1934	** 10,11 reserved for expansion
sl@0	1935	** N>=12 and even (N-12)/2 BLOB
sl@0	1936	** N>=13 and odd (N-13)/2 text
sl@0	1937	**
sl@0	1938	** The 8 and 9 types were added in 3.3.0, file format 4. Prior versions
sl@0	1939	** of SQLite will not understand those serial types.
sl@0	1940	*/
sl@0	1941
sl@0	1942	/*
sl@0	1943	** Return the serial-type for the value stored in pMem.
sl@0	1944	*/
sl@0	1945	u32 sqlite3VdbeSerialType(Mem *pMem, int file_format){
sl@0	1946	int flags = pMem->flags;
sl@0	1947	int n;
sl@0	1948
sl@0	1949	if( flags&MEM_Null ){
sl@0	1950	return 0;
sl@0	1951	}
sl@0	1952	if( flags&MEM_Int ){
sl@0	1953	/* Figure out whether to use 1, 2, 4, 6 or 8 bytes. */
sl@0	1954	# define MAX_6BYTE ((((i64)0x00008000)<<32)-1)
sl@0	1955	i64 i = pMem->u.i;
sl@0	1956	u64 u;
sl@0	1957	if( file_format>=4 && (i&1)==i ){
sl@0	1958	return 8+i;
sl@0	1959	}
sl@0	1960	u = i<0 ? -i : i;
sl@0	1961	if( u<=127 ) return 1;
sl@0	1962	if( u<=32767 ) return 2;
sl@0	1963	if( u<=8388607 ) return 3;
sl@0	1964	if( u<=2147483647 ) return 4;
sl@0	1965	if( u<=MAX_6BYTE ) return 5;
sl@0	1966	return 6;
sl@0	1967	}
sl@0	1968	if( flags&MEM_Real ){
sl@0	1969	return 7;
sl@0	1970	}
sl@0	1971	assert( flags&(MEM_Str\|MEM_Blob) );
sl@0	1972	n = pMem->n;
sl@0	1973	if( flags & MEM_Zero ){
sl@0	1974	n += pMem->u.i;
sl@0	1975	}
sl@0	1976	assert( n>=0 );
sl@0	1977	return ((n*2) + 12 + ((flags&MEM_Str)!=0));
sl@0	1978	}
sl@0	1979
sl@0	1980	/*
sl@0	1981	** Return the length of the data corresponding to the supplied serial-type.
sl@0	1982	*/
sl@0	1983	int sqlite3VdbeSerialTypeLen(u32 serial_type){
sl@0	1984	if( serial_type>=12 ){
sl@0	1985	return (serial_type-12)/2;
sl@0	1986	}else{
sl@0	1987	static const u8 aSize[] = { 0, 1, 2, 3, 4, 6, 8, 8, 0, 0, 0, 0 };
sl@0	1988	return aSize[serial_type];
sl@0	1989	}
sl@0	1990	}
sl@0	1991
sl@0	1992	/*
sl@0	1993	** If we are on an architecture with mixed-endian floating
sl@0	1994	** points (ex: ARM7) then swap the lower 4 bytes with the
sl@0	1995	** upper 4 bytes. Return the result.
sl@0	1996	**
sl@0	1997	** For most architectures, this is a no-op.
sl@0	1998	**
sl@0	1999	** (later): It is reported to me that the mixed-endian problem
sl@0	2000	** on ARM7 is an issue with GCC, not with the ARM7 chip. It seems
sl@0	2001	** that early versions of GCC stored the two words of a 64-bit
sl@0	2002	** float in the wrong order. And that error has been propagated
sl@0	2003	** ever since. The blame is not necessarily with GCC, though.
sl@0	2004	** GCC might have just copying the problem from a prior compiler.
sl@0	2005	** I am also told that newer versions of GCC that follow a different
sl@0	2006	** ABI get the byte order right.
sl@0	2007	**
sl@0	2008	** Developers using SQLite on an ARM7 should compile and run their
sl@0	2009	** application using -DSQLITE_DEBUG=1 at least once. With DEBUG
sl@0	2010	** enabled, some asserts below will ensure that the byte order of
sl@0	2011	** floating point values is correct.
sl@0	2012	**
sl@0	2013	** (2007-08-30) Frank van Vugt has studied this problem closely
sl@0	2014	** and has send his findings to the SQLite developers. Frank
sl@0	2015	** writes that some Linux kernels offer floating point hardware
sl@0	2016	** emulation that uses only 32-bit mantissas instead of a full
sl@0	2017	** 48-bits as required by the IEEE standard. (This is the
sl@0	2018	** CONFIG_FPE_FASTFPE option.) On such systems, floating point
sl@0	2019	** byte swapping becomes very complicated. To avoid problems,
sl@0	2020	** the necessary byte swapping is carried out using a 64-bit integer
sl@0	2021	** rather than a 64-bit float. Frank assures us that the code here
sl@0	2022	** works for him. We, the developers, have no way to independently
sl@0	2023	** verify this, but Frank seems to know what he is talking about
sl@0	2024	** so we trust him.
sl@0	2025	*/
sl@0	2026	#ifdef SQLITE_MIXED_ENDIAN_64BIT_FLOAT
sl@0	2027	static u64 floatSwap(u64 in){
sl@0	2028	union {
sl@0	2029	u64 r;
sl@0	2030	u32 i[2];
sl@0	2031	} u;
sl@0	2032	u32 t;
sl@0	2033
sl@0	2034	u.r = in;
sl@0	2035	t = u.i[0];
sl@0	2036	u.i[0] = u.i[1];
sl@0	2037	u.i[1] = t;
sl@0	2038	return u.r;
sl@0	2039	}
sl@0	2040	# define swapMixedEndianFloat(X) X = floatSwap(X)
sl@0	2041	#else
sl@0	2042	# define swapMixedEndianFloat(X)
sl@0	2043	#endif
sl@0	2044
sl@0	2045	/*
sl@0	2046	** Write the serialized data blob for the value stored in pMem into
sl@0	2047	** buf. It is assumed that the caller has allocated sufficient space.
sl@0	2048	** Return the number of bytes written.
sl@0	2049	**
sl@0	2050	** nBuf is the amount of space left in buf[]. nBuf must always be
sl@0	2051	** large enough to hold the entire field. Except, if the field is
sl@0	2052	** a blob with a zero-filled tail, then buf[] might be just the right
sl@0	2053	** size to hold everything except for the zero-filled tail. If buf[]
sl@0	2054	** is only big enough to hold the non-zero prefix, then only write that
sl@0	2055	** prefix into buf[]. But if buf[] is large enough to hold both the
sl@0	2056	** prefix and the tail then write the prefix and set the tail to all
sl@0	2057	** zeros.
sl@0	2058	**
sl@0	2059	** Return the number of bytes actually written into buf[]. The number
sl@0	2060	** of bytes in the zero-filled tail is included in the return value only
sl@0	2061	** if those bytes were zeroed in buf[].
sl@0	2062	*/
sl@0	2063	int sqlite3VdbeSerialPut(u8 buf, int nBuf, Mem pMem, int file_format){
sl@0	2064	u32 serial_type = sqlite3VdbeSerialType(pMem, file_format);
sl@0	2065	int len;
sl@0	2066
sl@0	2067	/* Integer and Real */
sl@0	2068	if( serial_type<=7 && serial_type>0 ){
sl@0	2069	u64 v;
sl@0	2070	int i;
sl@0	2071	if( serial_type==7 ){
sl@0	2072	assert( sizeof(v)==sizeof(pMem->r) );
sl@0	2073	memcpy(&v, &pMem->r, sizeof(v));
sl@0	2074	swapMixedEndianFloat(v);
sl@0	2075	}else{
sl@0	2076	v = pMem->u.i;
sl@0	2077	}
sl@0	2078	len = i = sqlite3VdbeSerialTypeLen(serial_type);
sl@0	2079	assert( len<=nBuf );
sl@0	2080	while( i-- ){
sl@0	2081	buf[i] = (v&0xFF);
sl@0	2082	v >>= 8;
sl@0	2083	}
sl@0	2084	return len;
sl@0	2085	}
sl@0	2086
sl@0	2087	/* String or blob */
sl@0	2088	if( serial_type>=12 ){
sl@0	2089	assert( pMem->n + ((pMem->flags & MEM_Zero)?pMem->u.i:0)
sl@0	2090	== sqlite3VdbeSerialTypeLen(serial_type) );
sl@0	2091	assert( pMem->n<=nBuf );
sl@0	2092	len = pMem->n;
sl@0	2093	memcpy(buf, pMem->z, len);
sl@0	2094	if( pMem->flags & MEM_Zero ){
sl@0	2095	len += pMem->u.i;
sl@0	2096	if( len>nBuf ){
sl@0	2097	len = nBuf;
sl@0	2098	}
sl@0	2099	memset(&buf[pMem->n], 0, len-pMem->n);
sl@0	2100	}
sl@0	2101	return len;
sl@0	2102	}
sl@0	2103
sl@0	2104	/* NULL or constants 0 or 1 */
sl@0	2105	return 0;
sl@0	2106	}
sl@0	2107
sl@0	2108	/*
sl@0	2109	** Deserialize the data blob pointed to by buf as serial type serial_type
sl@0	2110	** and store the result in pMem. Return the number of bytes read.
sl@0	2111	*/
sl@0	2112	int sqlite3VdbeSerialGet(
sl@0	2113	const unsigned char buf, / Buffer to deserialize from */
sl@0	2114	u32 serial_type, /* Serial type to deserialize */
sl@0	2115	Mem pMem / Memory cell to write value into */
sl@0	2116	){
sl@0	2117	switch( serial_type ){
sl@0	2118	case 10: /* Reserved for future use */
sl@0	2119	case 11: /* Reserved for future use */
sl@0	2120	case 0: { /* NULL */
sl@0	2121	pMem->flags = MEM_Null;
sl@0	2122	break;
sl@0	2123	}
sl@0	2124	case 1: { /* 1-byte signed integer */
sl@0	2125	pMem->u.i = (signed char)buf[0];
sl@0	2126	pMem->flags = MEM_Int;
sl@0	2127	return 1;
sl@0	2128	}
sl@0	2129	case 2: { /* 2-byte signed integer */
sl@0	2130	pMem->u.i = (((signed char)buf[0])<<8) \| buf[1];
sl@0	2131	pMem->flags = MEM_Int;
sl@0	2132	return 2;
sl@0	2133	}
sl@0	2134	case 3: { /* 3-byte signed integer */
sl@0	2135	pMem->u.i = (((signed char)buf[0])<<16) \| (buf[1]<<8) \| buf[2];
sl@0	2136	pMem->flags = MEM_Int;
sl@0	2137	return 3;
sl@0	2138	}
sl@0	2139	case 4: { /* 4-byte signed integer */
sl@0	2140	pMem->u.i = (buf[0]<<24) \| (buf[1]<<16) \| (buf[2]<<8) \| buf[3];
sl@0	2141	pMem->flags = MEM_Int;
sl@0	2142	return 4;
sl@0	2143	}
sl@0	2144	case 5: { /* 6-byte signed integer */
sl@0	2145	u64 x = (((signed char)buf[0])<<8) \| buf[1];
sl@0	2146	u32 y = (buf[2]<<24) \| (buf[3]<<16) \| (buf[4]<<8) \| buf[5];
sl@0	2147	x = (x<<32) \| y;
sl@0	2148	pMem->u.i = (i64)&x;
sl@0	2149	pMem->flags = MEM_Int;
sl@0	2150	return 6;
sl@0	2151	}
sl@0	2152	case 6: /* 8-byte signed integer */
sl@0	2153	case 7: { /* IEEE floating point */
sl@0	2154	u64 x;
sl@0	2155	u32 y;
sl@0	2156	#if !defined(NDEBUG) && !defined(SQLITE_OMIT_FLOATING_POINT)
sl@0	2157	/* Verify that integers and floating point values use the same
sl@0	2158	** byte order. Or, that if SQLITE_MIXED_ENDIAN_64BIT_FLOAT is
sl@0	2159	** defined that 64-bit floating point values really are mixed
sl@0	2160	** endian.
sl@0	2161	*/
sl@0	2162	static const u64 t1 = ((u64)0x3ff00000)<<32;
sl@0	2163	static const double r1 = 1.0;
sl@0	2164	u64 t2 = t1;
sl@0	2165	swapMixedEndianFloat(t2);
sl@0	2166	assert( sizeof(r1)==sizeof(t2) && memcmp(&r1, &t2, sizeof(r1))==0 );
sl@0	2167	#endif
sl@0	2168
sl@0	2169	x = (buf[0]<<24) \| (buf[1]<<16) \| (buf[2]<<8) \| buf[3];
sl@0	2170	y = (buf[4]<<24) \| (buf[5]<<16) \| (buf[6]<<8) \| buf[7];
sl@0	2171	x = (x<<32) \| y;
sl@0	2172	if( serial_type==6 ){
sl@0	2173	pMem->u.i = (i64)&x;
sl@0	2174	pMem->flags = MEM_Int;
sl@0	2175	}else{
sl@0	2176	assert( sizeof(x)==8 && sizeof(pMem->r)==8 );
sl@0	2177	swapMixedEndianFloat(x);
sl@0	2178	memcpy(&pMem->r, &x, sizeof(x));
sl@0	2179	pMem->flags = sqlite3IsNaN(pMem->r) ? MEM_Null : MEM_Real;
sl@0	2180	}
sl@0	2181	return 8;
sl@0	2182	}
sl@0	2183	case 8: /* Integer 0 */
sl@0	2184	case 9: { /* Integer 1 */
sl@0	2185	pMem->u.i = serial_type-8;
sl@0	2186	pMem->flags = MEM_Int;
sl@0	2187	return 0;
sl@0	2188	}
sl@0	2189	default: {
sl@0	2190	int len = (serial_type-12)/2;
sl@0	2191	pMem->z = (char *)buf;
sl@0	2192	pMem->n = len;
sl@0	2193	pMem->xDel = 0;
sl@0	2194	if( serial_type&0x01 ){
sl@0	2195	pMem->flags = MEM_Str \| MEM_Ephem;
sl@0	2196	}else{
sl@0	2197	pMem->flags = MEM_Blob \| MEM_Ephem;
sl@0	2198	}
sl@0	2199	return len;
sl@0	2200	}
sl@0	2201	}
sl@0	2202	return 0;
sl@0	2203	}
sl@0	2204
sl@0	2205
sl@0	2206	/*
sl@0	2207	** Given the nKey-byte encoding of a record in pKey[], parse the
sl@0	2208	** record into a UnpackedRecord structure. Return a pointer to
sl@0	2209	** that structure.
sl@0	2210	**
sl@0	2211	** The calling function might provide szSpace bytes of memory
sl@0	2212	** space at pSpace. This space can be used to hold the returned
sl@0	2213	** VDbeParsedRecord structure if it is large enough. If it is
sl@0	2214	** not big enough, space is obtained from sqlite3_malloc().
sl@0	2215	**
sl@0	2216	** The returned structure should be closed by a call to
sl@0	2217	** sqlite3VdbeDeleteUnpackedRecord().
sl@0	2218	*/
sl@0	2219	UnpackedRecord *sqlite3VdbeRecordUnpack(
sl@0	2220	KeyInfo pKeyInfo, / Information about the record format */
sl@0	2221	int nKey, /* Size of the binary record */
sl@0	2222	const void pKey, / The binary record */
sl@0	2223	UnpackedRecord pSpace,/ Space available to hold resulting object */
sl@0	2224	int szSpace /* Size of pSpace[] in bytes */
sl@0	2225	){
sl@0	2226	const unsigned char aKey = (const unsigned char )pKey;
sl@0	2227	UnpackedRecord *p;
sl@0	2228	int nByte;
sl@0	2229	int idx, d;
sl@0	2230	u16 u; /* Unsigned loop counter */
sl@0	2231	u32 szHdr;
sl@0	2232	Mem *pMem;
sl@0	2233
sl@0	2234	assert( sizeof(Mem)>sizeof(*p) );
sl@0	2235	nByte = sizeof(Mem)*(pKeyInfo->nField+2);
sl@0	2236	if( nByte>szSpace ){
sl@0	2237	p = sqlite3DbMallocRaw(pKeyInfo->db, nByte);
sl@0	2238	if( p==0 ) return 0;
sl@0	2239	p->flags = UNPACKED_NEED_FREE \| UNPACKED_NEED_DESTROY;
sl@0	2240	}else{
sl@0	2241	p = pSpace;
sl@0	2242	p->flags = UNPACKED_NEED_DESTROY;
sl@0	2243	}
sl@0	2244	p->pKeyInfo = pKeyInfo;
sl@0	2245	p->nField = pKeyInfo->nField + 1;
sl@0	2246	p->aMem = pMem = &((Mem*)p)[1];
sl@0	2247	idx = getVarint32(aKey, szHdr);
sl@0	2248	d = szHdr;
sl@0	2249	u = 0;
sl@0	2250	while( idx<szHdr && u<p->nField ){
sl@0	2251	u32 serial_type;
sl@0	2252
sl@0	2253	idx += getVarint32( aKey+idx, serial_type);
sl@0	2254	if( d>=nKey && sqlite3VdbeSerialTypeLen(serial_type)>0 ) break;
sl@0	2255	pMem->enc = pKeyInfo->enc;
sl@0	2256	pMem->db = pKeyInfo->db;
sl@0	2257	pMem->flags = 0;
sl@0	2258	pMem->zMalloc = 0;
sl@0	2259	d += sqlite3VdbeSerialGet(&aKey[d], serial_type, pMem);
sl@0	2260	pMem++;
sl@0	2261	u++;
sl@0	2262	}
sl@0	2263	assert( u<=pKeyInfo->nField + 1 );
sl@0	2264	p->nField = u;
sl@0	2265	return (void*)p;
sl@0	2266	}
sl@0	2267
sl@0	2268	/*
sl@0	2269	** This routine destroys a UnpackedRecord object
sl@0	2270	*/
sl@0	2271	void sqlite3VdbeDeleteUnpackedRecord(UnpackedRecord *p){
sl@0	2272	if( p ){
sl@0	2273	if( p->flags & UNPACKED_NEED_DESTROY ){
sl@0	2274	int i;
sl@0	2275	Mem *pMem;
sl@0	2276	for(i=0, pMem=p->aMem; i<p->nField; i++, pMem++){
sl@0	2277	if( pMem->zMalloc ){
sl@0	2278	sqlite3VdbeMemRelease(pMem);
sl@0	2279	}
sl@0	2280	}
sl@0	2281	}
sl@0	2282	if( p->flags & UNPACKED_NEED_FREE ){
sl@0	2283	sqlite3DbFree(p->pKeyInfo->db, p);
sl@0	2284	}
sl@0	2285	}
sl@0	2286	}
sl@0	2287
sl@0	2288	/*
sl@0	2289	** This function compares the two table rows or index records
sl@0	2290	** specified by {nKey1, pKey1} and pPKey2. It returns a negative, zero
sl@0	2291	** or positive integer if key1 is less than, equal to or
sl@0	2292	** greater than key2. The {nKey1, pKey1} key must be a blob
sl@0	2293	** created by th OP_MakeRecord opcode of the VDBE. The pPKey2
sl@0	2294	** key must be a parsed key such as obtained from
sl@0	2295	** sqlite3VdbeParseRecord.
sl@0	2296	**
sl@0	2297	** Key1 and Key2 do not have to contain the same number of fields.
sl@0	2298	** The key with fewer fields is usually compares less than the
sl@0	2299	** longer key. However if the UNPACKED_INCRKEY flags in pPKey2 is set
sl@0	2300	** and the common prefixes are equal, then key1 is less than key2.
sl@0	2301	** Or if the UNPACKED_MATCH_PREFIX flag is set and the prefixes are
sl@0	2302	** equal, then the keys are considered to be equal and
sl@0	2303	** the parts beyond the common prefix are ignored.
sl@0	2304	**
sl@0	2305	** If the UNPACKED_IGNORE_ROWID flag is set, then the last byte of
sl@0	2306	** the header of pKey1 is ignored. It is assumed that pKey1 is
sl@0	2307	** an index key, and thus ends with a rowid value. The last byte
sl@0	2308	** of the header will therefore be the serial type of the rowid:
sl@0	2309	** one of 1, 2, 3, 4, 5, 6, 8, or 9 - the integer serial types.
sl@0	2310	** The serial type of the final rowid will always be a single byte.
sl@0	2311	** By ignoring this last byte of the header, we force the comparison
sl@0	2312	** to ignore the rowid at the end of key1.
sl@0	2313	*/
sl@0	2314	int sqlite3VdbeRecordCompare(
sl@0	2315	int nKey1, const void pKey1, / Left key */
sl@0	2316	UnpackedRecord pPKey2 / Right key */
sl@0	2317	){
sl@0	2318	u32 d1; /* Offset into aKey[] of next data element */
sl@0	2319	u32 idx1; /* Offset into aKey[] of next header element */
sl@0	2320	u32 szHdr1; /* Number of bytes in header */
sl@0	2321	int i = 0;
sl@0	2322	int nField;
sl@0	2323	int rc = 0;
sl@0	2324	const unsigned char aKey1 = (const unsigned char )pKey1;
sl@0	2325	KeyInfo *pKeyInfo;
sl@0	2326	Mem mem1;
sl@0	2327
sl@0	2328	pKeyInfo = pPKey2->pKeyInfo;
sl@0	2329	mem1.enc = pKeyInfo->enc;
sl@0	2330	mem1.db = pKeyInfo->db;
sl@0	2331	mem1.flags = 0;
sl@0	2332	mem1.zMalloc = 0;
sl@0	2333
sl@0	2334	idx1 = getVarint32(aKey1, szHdr1);
sl@0	2335	d1 = szHdr1;
sl@0	2336	if( pPKey2->flags & UNPACKED_IGNORE_ROWID ){
sl@0	2337	szHdr1--;
sl@0	2338	}
sl@0	2339	nField = pKeyInfo->nField;
sl@0	2340	while( idx1<szHdr1 && i<pPKey2->nField ){
sl@0	2341	u32 serial_type1;
sl@0	2342
sl@0	2343	/* Read the serial types for the next element in each key. */
sl@0	2344	idx1 += getVarint32( aKey1+idx1, serial_type1 );
sl@0	2345	if( d1>=nKey1 && sqlite3VdbeSerialTypeLen(serial_type1)>0 ) break;
sl@0	2346
sl@0	2347	/* Extract the values to be compared.
sl@0	2348	*/
sl@0	2349	d1 += sqlite3VdbeSerialGet(&aKey1[d1], serial_type1, &mem1);
sl@0	2350
sl@0	2351	/* Do the comparison
sl@0	2352	*/
sl@0	2353	rc = sqlite3MemCompare(&mem1, &pPKey2->aMem[i],
sl@0	2354	i<nField ? pKeyInfo->aColl[i] : 0);
sl@0	2355	if( rc!=0 ){
sl@0	2356	break;
sl@0	2357	}
sl@0	2358	i++;
sl@0	2359	}
sl@0	2360	if( mem1.zMalloc ) sqlite3VdbeMemRelease(&mem1);
sl@0	2361
sl@0	2362	if( rc==0 ){
sl@0	2363	/* rc==0 here means that one of the keys ran out of fields and
sl@0	2364	** all the fields up to that point were equal. If the UNPACKED_INCRKEY
sl@0	2365	** flag is set, then break the tie by treating key2 as larger.
sl@0	2366	** If the UPACKED_PREFIX_MATCH flag is set, then keys with common prefixes
sl@0	2367	** are considered to be equal. Otherwise, the longer key is the
sl@0	2368	** larger. As it happens, the pPKey2 will always be the longer
sl@0	2369	** if there is a difference.
sl@0	2370	*/
sl@0	2371	if( pPKey2->flags & UNPACKED_INCRKEY ){
sl@0	2372	rc = -1;
sl@0	2373	}else if( pPKey2->flags & UNPACKED_PREFIX_MATCH ){
sl@0	2374	/* Leave rc==0 */
sl@0	2375	}else if( idx1<szHdr1 ){
sl@0	2376	rc = 1;
sl@0	2377	}
sl@0	2378	}else if( pKeyInfo->aSortOrder && i<pKeyInfo->nField
sl@0	2379	&& pKeyInfo->aSortOrder[i] ){
sl@0	2380	rc = -rc;
sl@0	2381	}
sl@0	2382
sl@0	2383	return rc;
sl@0	2384	}
sl@0	2385
sl@0	2386
sl@0	2387	/*
sl@0	2388	** pCur points at an index entry created using the OP_MakeRecord opcode.
sl@0	2389	** Read the rowid (the last field in the record) and store it in *rowid.
sl@0	2390	** Return SQLITE_OK if everything works, or an error code otherwise.
sl@0	2391	*/
sl@0	2392	int sqlite3VdbeIdxRowid(BtCursor pCur, i64 rowid){
sl@0	2393	i64 nCellKey = 0;
sl@0	2394	int rc;
sl@0	2395	u32 szHdr; /* Size of the header */
sl@0	2396	u32 typeRowid; /* Serial type of the rowid */
sl@0	2397	u32 lenRowid; /* Size of the rowid */
sl@0	2398	Mem m, v;
sl@0	2399
sl@0	2400	sqlite3BtreeKeySize(pCur, &nCellKey);
sl@0	2401	if( nCellKey<=0 ){
sl@0	2402	return SQLITE_CORRUPT_BKPT;
sl@0	2403	}
sl@0	2404	m.flags = 0;
sl@0	2405	m.db = 0;
sl@0	2406	m.zMalloc = 0;
sl@0	2407	rc = sqlite3VdbeMemFromBtree(pCur, 0, nCellKey, 1, &m);
sl@0	2408	if( rc ){
sl@0	2409	return rc;
sl@0	2410	}
sl@0	2411	(void)getVarint32((u8*)m.z, szHdr);
sl@0	2412	(void)getVarint32((u8*)&m.z[szHdr-1], typeRowid);
sl@0	2413	lenRowid = sqlite3VdbeSerialTypeLen(typeRowid);
sl@0	2414	sqlite3VdbeSerialGet((u8*)&m.z[m.n-lenRowid], typeRowid, &v);
sl@0	2415	*rowid = v.u.i;
sl@0	2416	sqlite3VdbeMemRelease(&m);
sl@0	2417	return SQLITE_OK;
sl@0	2418	}
sl@0	2419
sl@0	2420	/*
sl@0	2421	** Compare the key of the index entry that cursor pC is point to against
sl@0	2422	** the key string in pKey (of length nKey). Write into *pRes a number
sl@0	2423	** that is negative, zero, or positive if pC is less than, equal to,
sl@0	2424	** or greater than pKey. Return SQLITE_OK on success.
sl@0	2425	**
sl@0	2426	** pKey is either created without a rowid or is truncated so that it
sl@0	2427	** omits the rowid at the end. The rowid at the end of the index entry
sl@0	2428	** is ignored as well. Hence, this routine only compares the prefixes
sl@0	2429	** of the keys prior to the final rowid, not the entire key.
sl@0	2430	**
sl@0	2431	** pUnpacked may be an unpacked version of pKey,nKey. If pUnpacked is
sl@0	2432	** supplied it is used in place of pKey,nKey.
sl@0	2433	*/
sl@0	2434	int sqlite3VdbeIdxKeyCompare(
sl@0	2435	Cursor pC, / The cursor to compare against */
sl@0	2436	UnpackedRecord pUnpacked, / Unpacked version of pKey and nKey */
sl@0	2437	int res / Write the comparison result here */
sl@0	2438	){
sl@0	2439	i64 nCellKey = 0;
sl@0	2440	int rc;
sl@0	2441	BtCursor *pCur = pC->pCursor;
sl@0	2442	Mem m;
sl@0	2443
sl@0	2444	sqlite3BtreeKeySize(pCur, &nCellKey);
sl@0	2445	if( nCellKey<=0 ){
sl@0	2446	*res = 0;
sl@0	2447	return SQLITE_OK;
sl@0	2448	}
sl@0	2449	m.db = 0;
sl@0	2450	m.flags = 0;
sl@0	2451	m.zMalloc = 0;
sl@0	2452	rc = sqlite3VdbeMemFromBtree(pC->pCursor, 0, nCellKey, 1, &m);
sl@0	2453	if( rc ){
sl@0	2454	return rc;
sl@0	2455	}
sl@0	2456	assert( pUnpacked->flags & UNPACKED_IGNORE_ROWID );
sl@0	2457	*res = sqlite3VdbeRecordCompare(m.n, m.z, pUnpacked);
sl@0	2458	sqlite3VdbeMemRelease(&m);
sl@0	2459	return SQLITE_OK;
sl@0	2460	}
sl@0	2461
sl@0	2462	/*
sl@0	2463	** This routine sets the value to be returned by subsequent calls to
sl@0	2464	** sqlite3_changes() on the database handle 'db'.
sl@0	2465	*/
sl@0	2466	void sqlite3VdbeSetChanges(sqlite3 *db, int nChange){
sl@0	2467	assert( sqlite3_mutex_held(db->mutex) );
sl@0	2468	db->nChange = nChange;
sl@0	2469	db->nTotalChange += nChange;
sl@0	2470	}
sl@0	2471
sl@0	2472	/*
sl@0	2473	** Set a flag in the vdbe to update the change counter when it is finalised
sl@0	2474	** or reset.
sl@0	2475	*/
sl@0	2476	void sqlite3VdbeCountChanges(Vdbe *v){
sl@0	2477	v->changeCntOn = 1;
sl@0	2478	}
sl@0	2479
sl@0	2480	/*
sl@0	2481	** Mark every prepared statement associated with a database connection
sl@0	2482	** as expired.
sl@0	2483	**
sl@0	2484	** An expired statement means that recompilation of the statement is
sl@0	2485	** recommend. Statements expire when things happen that make their
sl@0	2486	** programs obsolete. Removing user-defined functions or collating
sl@0	2487	** sequences, or changing an authorization function are the types of
sl@0	2488	** things that make prepared statements obsolete.
sl@0	2489	*/
sl@0	2490	void sqlite3ExpirePreparedStatements(sqlite3 *db){
sl@0	2491	Vdbe *p;
sl@0	2492	for(p = db->pVdbe; p; p=p->pNext){
sl@0	2493	p->expired = 1;
sl@0	2494	}
sl@0	2495	}
sl@0	2496
sl@0	2497	/*
sl@0	2498	** Return the database associated with the Vdbe.
sl@0	2499	*/
sl@0	2500	sqlite3 sqlite3VdbeDb(Vdbe v){
sl@0	2501	return v->db;
sl@0	2502	}

author	sl@SLION-WIN7.fritz.box
	Fri, 15 Jun 2012 03:10:57 +0200
changeset 0	bde4ae8d615e
permissions	-rw-r--r--