Annotation of embedaddon/sqlite3/src/vdbeaux.c, revision 1.1.1.1
1.1 misho 1: /*
2: ** 2003 September 6
3: **
4: ** The author disclaims copyright to this source code. In place of
5: ** a legal notice, here is a blessing:
6: **
7: ** May you do good and not evil.
8: ** May you find forgiveness for yourself and forgive others.
9: ** May you share freely, never taking more than you give.
10: **
11: *************************************************************************
12: ** This file contains code used for creating, destroying, and populating
13: ** a VDBE (or an "sqlite3_stmt" as it is known to the outside world.) Prior
14: ** to version 2.8.7, all this code was combined into the vdbe.c source file.
15: ** But that file was getting too big so this subroutines were split out.
16: */
17: #include "sqliteInt.h"
18: #include "vdbeInt.h"
19:
20:
21:
22: /*
23: ** When debugging the code generator in a symbolic debugger, one can
24: ** set the sqlite3VdbeAddopTrace to 1 and all opcodes will be printed
25: ** as they are added to the instruction stream.
26: */
27: #ifdef SQLITE_DEBUG
28: int sqlite3VdbeAddopTrace = 0;
29: #endif
30:
31:
32: /*
33: ** Create a new virtual database engine.
34: */
35: Vdbe *sqlite3VdbeCreate(sqlite3 *db){
36: Vdbe *p;
37: p = sqlite3DbMallocZero(db, sizeof(Vdbe) );
38: if( p==0 ) return 0;
39: p->db = db;
40: if( db->pVdbe ){
41: db->pVdbe->pPrev = p;
42: }
43: p->pNext = db->pVdbe;
44: p->pPrev = 0;
45: db->pVdbe = p;
46: p->magic = VDBE_MAGIC_INIT;
47: return p;
48: }
49:
50: /*
51: ** Remember the SQL string for a prepared statement.
52: */
53: void sqlite3VdbeSetSql(Vdbe *p, const char *z, int n, int isPrepareV2){
54: assert( isPrepareV2==1 || isPrepareV2==0 );
55: if( p==0 ) return;
56: #ifdef SQLITE_OMIT_TRACE
57: if( !isPrepareV2 ) return;
58: #endif
59: assert( p->zSql==0 );
60: p->zSql = sqlite3DbStrNDup(p->db, z, n);
61: p->isPrepareV2 = (u8)isPrepareV2;
62: }
63:
64: /*
65: ** Return the SQL associated with a prepared statement
66: */
67: const char *sqlite3_sql(sqlite3_stmt *pStmt){
68: Vdbe *p = (Vdbe *)pStmt;
69: return (p && p->isPrepareV2) ? p->zSql : 0;
70: }
71:
72: /*
73: ** Swap all content between two VDBE structures.
74: */
75: void sqlite3VdbeSwap(Vdbe *pA, Vdbe *pB){
76: Vdbe tmp, *pTmp;
77: char *zTmp;
78: tmp = *pA;
79: *pA = *pB;
80: *pB = tmp;
81: pTmp = pA->pNext;
82: pA->pNext = pB->pNext;
83: pB->pNext = pTmp;
84: pTmp = pA->pPrev;
85: pA->pPrev = pB->pPrev;
86: pB->pPrev = pTmp;
87: zTmp = pA->zSql;
88: pA->zSql = pB->zSql;
89: pB->zSql = zTmp;
90: pB->isPrepareV2 = pA->isPrepareV2;
91: }
92:
93: #ifdef SQLITE_DEBUG
94: /*
95: ** Turn tracing on or off
96: */
97: void sqlite3VdbeTrace(Vdbe *p, FILE *trace){
98: p->trace = trace;
99: }
100: #endif
101:
102: /*
103: ** Resize the Vdbe.aOp array so that it is at least one op larger than
104: ** it was.
105: **
106: ** If an out-of-memory error occurs while resizing the array, return
107: ** SQLITE_NOMEM. In this case Vdbe.aOp and Vdbe.nOpAlloc remain
108: ** unchanged (this is so that any opcodes already allocated can be
109: ** correctly deallocated along with the rest of the Vdbe).
110: */
111: static int growOpArray(Vdbe *p){
112: VdbeOp *pNew;
113: int nNew = (p->nOpAlloc ? p->nOpAlloc*2 : (int)(1024/sizeof(Op)));
114: pNew = sqlite3DbRealloc(p->db, p->aOp, nNew*sizeof(Op));
115: if( pNew ){
116: p->nOpAlloc = sqlite3DbMallocSize(p->db, pNew)/sizeof(Op);
117: p->aOp = pNew;
118: }
119: return (pNew ? SQLITE_OK : SQLITE_NOMEM);
120: }
121:
122: /*
123: ** Add a new instruction to the list of instructions current in the
124: ** VDBE. Return the address of the new instruction.
125: **
126: ** Parameters:
127: **
128: ** p Pointer to the VDBE
129: **
130: ** op The opcode for this instruction
131: **
132: ** p1, p2, p3 Operands
133: **
134: ** Use the sqlite3VdbeResolveLabel() function to fix an address and
135: ** the sqlite3VdbeChangeP4() function to change the value of the P4
136: ** operand.
137: */
138: int sqlite3VdbeAddOp3(Vdbe *p, int op, int p1, int p2, int p3){
139: int i;
140: VdbeOp *pOp;
141:
142: i = p->nOp;
143: assert( p->magic==VDBE_MAGIC_INIT );
144: assert( op>0 && op<0xff );
145: if( p->nOpAlloc<=i ){
146: if( growOpArray(p) ){
147: return 1;
148: }
149: }
150: p->nOp++;
151: pOp = &p->aOp[i];
152: pOp->opcode = (u8)op;
153: pOp->p5 = 0;
154: pOp->p1 = p1;
155: pOp->p2 = p2;
156: pOp->p3 = p3;
157: pOp->p4.p = 0;
158: pOp->p4type = P4_NOTUSED;
159: #ifdef SQLITE_DEBUG
160: pOp->zComment = 0;
161: if( sqlite3VdbeAddopTrace ) sqlite3VdbePrintOp(0, i, &p->aOp[i]);
162: #endif
163: #ifdef VDBE_PROFILE
164: pOp->cycles = 0;
165: pOp->cnt = 0;
166: #endif
167: return i;
168: }
169: int sqlite3VdbeAddOp0(Vdbe *p, int op){
170: return sqlite3VdbeAddOp3(p, op, 0, 0, 0);
171: }
172: int sqlite3VdbeAddOp1(Vdbe *p, int op, int p1){
173: return sqlite3VdbeAddOp3(p, op, p1, 0, 0);
174: }
175: int sqlite3VdbeAddOp2(Vdbe *p, int op, int p1, int p2){
176: return sqlite3VdbeAddOp3(p, op, p1, p2, 0);
177: }
178:
179:
180: /*
181: ** Add an opcode that includes the p4 value as a pointer.
182: */
183: int sqlite3VdbeAddOp4(
184: Vdbe *p, /* Add the opcode to this VM */
185: int op, /* The new opcode */
186: int p1, /* The P1 operand */
187: int p2, /* The P2 operand */
188: int p3, /* The P3 operand */
189: const char *zP4, /* The P4 operand */
190: int p4type /* P4 operand type */
191: ){
192: int addr = sqlite3VdbeAddOp3(p, op, p1, p2, p3);
193: sqlite3VdbeChangeP4(p, addr, zP4, p4type);
194: return addr;
195: }
196:
197: /*
198: ** Add an OP_ParseSchema opcode. This routine is broken out from
199: ** sqlite3VdbeAddOp4() since it needs to also needs to mark all btrees
200: ** as having been used.
201: **
202: ** The zWhere string must have been obtained from sqlite3_malloc().
203: ** This routine will take ownership of the allocated memory.
204: */
205: void sqlite3VdbeAddParseSchemaOp(Vdbe *p, int iDb, char *zWhere){
206: int j;
207: int addr = sqlite3VdbeAddOp3(p, OP_ParseSchema, iDb, 0, 0);
208: sqlite3VdbeChangeP4(p, addr, zWhere, P4_DYNAMIC);
209: for(j=0; j<p->db->nDb; j++) sqlite3VdbeUsesBtree(p, j);
210: }
211:
212: /*
213: ** Add an opcode that includes the p4 value as an integer.
214: */
215: int sqlite3VdbeAddOp4Int(
216: Vdbe *p, /* Add the opcode to this VM */
217: int op, /* The new opcode */
218: int p1, /* The P1 operand */
219: int p2, /* The P2 operand */
220: int p3, /* The P3 operand */
221: int p4 /* The P4 operand as an integer */
222: ){
223: int addr = sqlite3VdbeAddOp3(p, op, p1, p2, p3);
224: sqlite3VdbeChangeP4(p, addr, SQLITE_INT_TO_PTR(p4), P4_INT32);
225: return addr;
226: }
227:
228: /*
229: ** Create a new symbolic label for an instruction that has yet to be
230: ** coded. The symbolic label is really just a negative number. The
231: ** label can be used as the P2 value of an operation. Later, when
232: ** the label is resolved to a specific address, the VDBE will scan
233: ** through its operation list and change all values of P2 which match
234: ** the label into the resolved address.
235: **
236: ** The VDBE knows that a P2 value is a label because labels are
237: ** always negative and P2 values are suppose to be non-negative.
238: ** Hence, a negative P2 value is a label that has yet to be resolved.
239: **
240: ** Zero is returned if a malloc() fails.
241: */
242: int sqlite3VdbeMakeLabel(Vdbe *p){
243: int i;
244: i = p->nLabel++;
245: assert( p->magic==VDBE_MAGIC_INIT );
246: if( i>=p->nLabelAlloc ){
247: int n = p->nLabelAlloc*2 + 5;
248: p->aLabel = sqlite3DbReallocOrFree(p->db, p->aLabel,
249: n*sizeof(p->aLabel[0]));
250: p->nLabelAlloc = sqlite3DbMallocSize(p->db, p->aLabel)/sizeof(p->aLabel[0]);
251: }
252: if( p->aLabel ){
253: p->aLabel[i] = -1;
254: }
255: return -1-i;
256: }
257:
258: /*
259: ** Resolve label "x" to be the address of the next instruction to
260: ** be inserted. The parameter "x" must have been obtained from
261: ** a prior call to sqlite3VdbeMakeLabel().
262: */
263: void sqlite3VdbeResolveLabel(Vdbe *p, int x){
264: int j = -1-x;
265: assert( p->magic==VDBE_MAGIC_INIT );
266: assert( j>=0 && j<p->nLabel );
267: if( p->aLabel ){
268: p->aLabel[j] = p->nOp;
269: }
270: }
271:
272: /*
273: ** Mark the VDBE as one that can only be run one time.
274: */
275: void sqlite3VdbeRunOnlyOnce(Vdbe *p){
276: p->runOnlyOnce = 1;
277: }
278:
279: #ifdef SQLITE_DEBUG /* sqlite3AssertMayAbort() logic */
280:
281: /*
282: ** The following type and function are used to iterate through all opcodes
283: ** in a Vdbe main program and each of the sub-programs (triggers) it may
284: ** invoke directly or indirectly. It should be used as follows:
285: **
286: ** Op *pOp;
287: ** VdbeOpIter sIter;
288: **
289: ** memset(&sIter, 0, sizeof(sIter));
290: ** sIter.v = v; // v is of type Vdbe*
291: ** while( (pOp = opIterNext(&sIter)) ){
292: ** // Do something with pOp
293: ** }
294: ** sqlite3DbFree(v->db, sIter.apSub);
295: **
296: */
297: typedef struct VdbeOpIter VdbeOpIter;
298: struct VdbeOpIter {
299: Vdbe *v; /* Vdbe to iterate through the opcodes of */
300: SubProgram **apSub; /* Array of subprograms */
301: int nSub; /* Number of entries in apSub */
302: int iAddr; /* Address of next instruction to return */
303: int iSub; /* 0 = main program, 1 = first sub-program etc. */
304: };
305: static Op *opIterNext(VdbeOpIter *p){
306: Vdbe *v = p->v;
307: Op *pRet = 0;
308: Op *aOp;
309: int nOp;
310:
311: if( p->iSub<=p->nSub ){
312:
313: if( p->iSub==0 ){
314: aOp = v->aOp;
315: nOp = v->nOp;
316: }else{
317: aOp = p->apSub[p->iSub-1]->aOp;
318: nOp = p->apSub[p->iSub-1]->nOp;
319: }
320: assert( p->iAddr<nOp );
321:
322: pRet = &aOp[p->iAddr];
323: p->iAddr++;
324: if( p->iAddr==nOp ){
325: p->iSub++;
326: p->iAddr = 0;
327: }
328:
329: if( pRet->p4type==P4_SUBPROGRAM ){
330: int nByte = (p->nSub+1)*sizeof(SubProgram*);
331: int j;
332: for(j=0; j<p->nSub; j++){
333: if( p->apSub[j]==pRet->p4.pProgram ) break;
334: }
335: if( j==p->nSub ){
336: p->apSub = sqlite3DbReallocOrFree(v->db, p->apSub, nByte);
337: if( !p->apSub ){
338: pRet = 0;
339: }else{
340: p->apSub[p->nSub++] = pRet->p4.pProgram;
341: }
342: }
343: }
344: }
345:
346: return pRet;
347: }
348:
349: /*
350: ** Check if the program stored in the VM associated with pParse may
351: ** throw an ABORT exception (causing the statement, but not entire transaction
352: ** to be rolled back). This condition is true if the main program or any
353: ** sub-programs contains any of the following:
354: **
355: ** * OP_Halt with P1=SQLITE_CONSTRAINT and P2=OE_Abort.
356: ** * OP_HaltIfNull with P1=SQLITE_CONSTRAINT and P2=OE_Abort.
357: ** * OP_Destroy
358: ** * OP_VUpdate
359: ** * OP_VRename
360: ** * OP_FkCounter with P2==0 (immediate foreign key constraint)
361: **
362: ** Then check that the value of Parse.mayAbort is true if an
363: ** ABORT may be thrown, or false otherwise. Return true if it does
364: ** match, or false otherwise. This function is intended to be used as
365: ** part of an assert statement in the compiler. Similar to:
366: **
367: ** assert( sqlite3VdbeAssertMayAbort(pParse->pVdbe, pParse->mayAbort) );
368: */
369: int sqlite3VdbeAssertMayAbort(Vdbe *v, int mayAbort){
370: int hasAbort = 0;
371: Op *pOp;
372: VdbeOpIter sIter;
373: memset(&sIter, 0, sizeof(sIter));
374: sIter.v = v;
375:
376: while( (pOp = opIterNext(&sIter))!=0 ){
377: int opcode = pOp->opcode;
378: if( opcode==OP_Destroy || opcode==OP_VUpdate || opcode==OP_VRename
379: #ifndef SQLITE_OMIT_FOREIGN_KEY
380: || (opcode==OP_FkCounter && pOp->p1==0 && pOp->p2==1)
381: #endif
382: || ((opcode==OP_Halt || opcode==OP_HaltIfNull)
383: && (pOp->p1==SQLITE_CONSTRAINT && pOp->p2==OE_Abort))
384: ){
385: hasAbort = 1;
386: break;
387: }
388: }
389: sqlite3DbFree(v->db, sIter.apSub);
390:
391: /* Return true if hasAbort==mayAbort. Or if a malloc failure occured.
392: ** If malloc failed, then the while() loop above may not have iterated
393: ** through all opcodes and hasAbort may be set incorrectly. Return
394: ** true for this case to prevent the assert() in the callers frame
395: ** from failing. */
396: return ( v->db->mallocFailed || hasAbort==mayAbort );
397: }
398: #endif /* SQLITE_DEBUG - the sqlite3AssertMayAbort() function */
399:
400: /*
401: ** Loop through the program looking for P2 values that are negative
402: ** on jump instructions. Each such value is a label. Resolve the
403: ** label by setting the P2 value to its correct non-zero value.
404: **
405: ** This routine is called once after all opcodes have been inserted.
406: **
407: ** Variable *pMaxFuncArgs is set to the maximum value of any P2 argument
408: ** to an OP_Function, OP_AggStep or OP_VFilter opcode. This is used by
409: ** sqlite3VdbeMakeReady() to size the Vdbe.apArg[] array.
410: **
411: ** The Op.opflags field is set on all opcodes.
412: */
413: static void resolveP2Values(Vdbe *p, int *pMaxFuncArgs){
414: int i;
415: int nMaxArgs = *pMaxFuncArgs;
416: Op *pOp;
417: int *aLabel = p->aLabel;
418: p->readOnly = 1;
419: for(pOp=p->aOp, i=p->nOp-1; i>=0; i--, pOp++){
420: u8 opcode = pOp->opcode;
421:
422: pOp->opflags = sqlite3OpcodeProperty[opcode];
423: if( opcode==OP_Function || opcode==OP_AggStep ){
424: if( pOp->p5>nMaxArgs ) nMaxArgs = pOp->p5;
425: }else if( (opcode==OP_Transaction && pOp->p2!=0) || opcode==OP_Vacuum ){
426: p->readOnly = 0;
427: #ifndef SQLITE_OMIT_VIRTUALTABLE
428: }else if( opcode==OP_VUpdate ){
429: if( pOp->p2>nMaxArgs ) nMaxArgs = pOp->p2;
430: }else if( opcode==OP_VFilter ){
431: int n;
432: assert( p->nOp - i >= 3 );
433: assert( pOp[-1].opcode==OP_Integer );
434: n = pOp[-1].p1;
435: if( n>nMaxArgs ) nMaxArgs = n;
436: #endif
437: }else if( opcode==OP_Next || opcode==OP_SorterNext ){
438: pOp->p4.xAdvance = sqlite3BtreeNext;
439: pOp->p4type = P4_ADVANCE;
440: }else if( opcode==OP_Prev ){
441: pOp->p4.xAdvance = sqlite3BtreePrevious;
442: pOp->p4type = P4_ADVANCE;
443: }
444:
445: if( (pOp->opflags & OPFLG_JUMP)!=0 && pOp->p2<0 ){
446: assert( -1-pOp->p2<p->nLabel );
447: pOp->p2 = aLabel[-1-pOp->p2];
448: }
449: }
450: sqlite3DbFree(p->db, p->aLabel);
451: p->aLabel = 0;
452:
453: *pMaxFuncArgs = nMaxArgs;
454: }
455:
456: /*
457: ** Return the address of the next instruction to be inserted.
458: */
459: int sqlite3VdbeCurrentAddr(Vdbe *p){
460: assert( p->magic==VDBE_MAGIC_INIT );
461: return p->nOp;
462: }
463:
464: /*
465: ** This function returns a pointer to the array of opcodes associated with
466: ** the Vdbe passed as the first argument. It is the callers responsibility
467: ** to arrange for the returned array to be eventually freed using the
468: ** vdbeFreeOpArray() function.
469: **
470: ** Before returning, *pnOp is set to the number of entries in the returned
471: ** array. Also, *pnMaxArg is set to the larger of its current value and
472: ** the number of entries in the Vdbe.apArg[] array required to execute the
473: ** returned program.
474: */
475: VdbeOp *sqlite3VdbeTakeOpArray(Vdbe *p, int *pnOp, int *pnMaxArg){
476: VdbeOp *aOp = p->aOp;
477: assert( aOp && !p->db->mallocFailed );
478:
479: /* Check that sqlite3VdbeUsesBtree() was not called on this VM */
480: assert( p->btreeMask==0 );
481:
482: resolveP2Values(p, pnMaxArg);
483: *pnOp = p->nOp;
484: p->aOp = 0;
485: return aOp;
486: }
487:
488: /*
489: ** Add a whole list of operations to the operation stack. Return the
490: ** address of the first operation added.
491: */
492: int sqlite3VdbeAddOpList(Vdbe *p, int nOp, VdbeOpList const *aOp){
493: int addr;
494: assert( p->magic==VDBE_MAGIC_INIT );
495: if( p->nOp + nOp > p->nOpAlloc && growOpArray(p) ){
496: return 0;
497: }
498: addr = p->nOp;
499: if( ALWAYS(nOp>0) ){
500: int i;
501: VdbeOpList const *pIn = aOp;
502: for(i=0; i<nOp; i++, pIn++){
503: int p2 = pIn->p2;
504: VdbeOp *pOut = &p->aOp[i+addr];
505: pOut->opcode = pIn->opcode;
506: pOut->p1 = pIn->p1;
507: if( p2<0 && (sqlite3OpcodeProperty[pOut->opcode] & OPFLG_JUMP)!=0 ){
508: pOut->p2 = addr + ADDR(p2);
509: }else{
510: pOut->p2 = p2;
511: }
512: pOut->p3 = pIn->p3;
513: pOut->p4type = P4_NOTUSED;
514: pOut->p4.p = 0;
515: pOut->p5 = 0;
516: #ifdef SQLITE_DEBUG
517: pOut->zComment = 0;
518: if( sqlite3VdbeAddopTrace ){
519: sqlite3VdbePrintOp(0, i+addr, &p->aOp[i+addr]);
520: }
521: #endif
522: }
523: p->nOp += nOp;
524: }
525: return addr;
526: }
527:
528: /*
529: ** Change the value of the P1 operand for a specific instruction.
530: ** This routine is useful when a large program is loaded from a
531: ** static array using sqlite3VdbeAddOpList but we want to make a
532: ** few minor changes to the program.
533: */
534: void sqlite3VdbeChangeP1(Vdbe *p, u32 addr, int val){
535: assert( p!=0 );
536: if( ((u32)p->nOp)>addr ){
537: p->aOp[addr].p1 = val;
538: }
539: }
540:
541: /*
542: ** Change the value of the P2 operand for a specific instruction.
543: ** This routine is useful for setting a jump destination.
544: */
545: void sqlite3VdbeChangeP2(Vdbe *p, u32 addr, int val){
546: assert( p!=0 );
547: if( ((u32)p->nOp)>addr ){
548: p->aOp[addr].p2 = val;
549: }
550: }
551:
552: /*
553: ** Change the value of the P3 operand for a specific instruction.
554: */
555: void sqlite3VdbeChangeP3(Vdbe *p, u32 addr, int val){
556: assert( p!=0 );
557: if( ((u32)p->nOp)>addr ){
558: p->aOp[addr].p3 = val;
559: }
560: }
561:
562: /*
563: ** Change the value of the P5 operand for the most recently
564: ** added operation.
565: */
566: void sqlite3VdbeChangeP5(Vdbe *p, u8 val){
567: assert( p!=0 );
568: if( p->aOp ){
569: assert( p->nOp>0 );
570: p->aOp[p->nOp-1].p5 = val;
571: }
572: }
573:
574: /*
575: ** Change the P2 operand of instruction addr so that it points to
576: ** the address of the next instruction to be coded.
577: */
578: void sqlite3VdbeJumpHere(Vdbe *p, int addr){
579: assert( addr>=0 || p->db->mallocFailed );
580: if( addr>=0 ) sqlite3VdbeChangeP2(p, addr, p->nOp);
581: }
582:
583:
584: /*
585: ** If the input FuncDef structure is ephemeral, then free it. If
586: ** the FuncDef is not ephermal, then do nothing.
587: */
588: static void freeEphemeralFunction(sqlite3 *db, FuncDef *pDef){
589: if( ALWAYS(pDef) && (pDef->flags & SQLITE_FUNC_EPHEM)!=0 ){
590: sqlite3DbFree(db, pDef);
591: }
592: }
593:
594: static void vdbeFreeOpArray(sqlite3 *, Op *, int);
595:
596: /*
597: ** Delete a P4 value if necessary.
598: */
599: static void freeP4(sqlite3 *db, int p4type, void *p4){
600: if( p4 ){
601: assert( db );
602: switch( p4type ){
603: case P4_REAL:
604: case P4_INT64:
605: case P4_DYNAMIC:
606: case P4_KEYINFO:
607: case P4_INTARRAY:
608: case P4_KEYINFO_HANDOFF: {
609: sqlite3DbFree(db, p4);
610: break;
611: }
612: case P4_MPRINTF: {
613: if( db->pnBytesFreed==0 ) sqlite3_free(p4);
614: break;
615: }
616: case P4_VDBEFUNC: {
617: VdbeFunc *pVdbeFunc = (VdbeFunc *)p4;
618: freeEphemeralFunction(db, pVdbeFunc->pFunc);
619: if( db->pnBytesFreed==0 ) sqlite3VdbeDeleteAuxData(pVdbeFunc, 0);
620: sqlite3DbFree(db, pVdbeFunc);
621: break;
622: }
623: case P4_FUNCDEF: {
624: freeEphemeralFunction(db, (FuncDef*)p4);
625: break;
626: }
627: case P4_MEM: {
628: if( db->pnBytesFreed==0 ){
629: sqlite3ValueFree((sqlite3_value*)p4);
630: }else{
631: Mem *p = (Mem*)p4;
632: sqlite3DbFree(db, p->zMalloc);
633: sqlite3DbFree(db, p);
634: }
635: break;
636: }
637: case P4_VTAB : {
638: if( db->pnBytesFreed==0 ) sqlite3VtabUnlock((VTable *)p4);
639: break;
640: }
641: }
642: }
643: }
644:
645: /*
646: ** Free the space allocated for aOp and any p4 values allocated for the
647: ** opcodes contained within. If aOp is not NULL it is assumed to contain
648: ** nOp entries.
649: */
650: static void vdbeFreeOpArray(sqlite3 *db, Op *aOp, int nOp){
651: if( aOp ){
652: Op *pOp;
653: for(pOp=aOp; pOp<&aOp[nOp]; pOp++){
654: freeP4(db, pOp->p4type, pOp->p4.p);
655: #ifdef SQLITE_DEBUG
656: sqlite3DbFree(db, pOp->zComment);
657: #endif
658: }
659: }
660: sqlite3DbFree(db, aOp);
661: }
662:
663: /*
664: ** Link the SubProgram object passed as the second argument into the linked
665: ** list at Vdbe.pSubProgram. This list is used to delete all sub-program
666: ** objects when the VM is no longer required.
667: */
668: void sqlite3VdbeLinkSubProgram(Vdbe *pVdbe, SubProgram *p){
669: p->pNext = pVdbe->pProgram;
670: pVdbe->pProgram = p;
671: }
672:
673: /*
674: ** Change the opcode at addr into OP_Noop
675: */
676: void sqlite3VdbeChangeToNoop(Vdbe *p, int addr){
677: if( p->aOp ){
678: VdbeOp *pOp = &p->aOp[addr];
679: sqlite3 *db = p->db;
680: freeP4(db, pOp->p4type, pOp->p4.p);
681: memset(pOp, 0, sizeof(pOp[0]));
682: pOp->opcode = OP_Noop;
683: }
684: }
685:
686: /*
687: ** Change the value of the P4 operand for a specific instruction.
688: ** This routine is useful when a large program is loaded from a
689: ** static array using sqlite3VdbeAddOpList but we want to make a
690: ** few minor changes to the program.
691: **
692: ** If n>=0 then the P4 operand is dynamic, meaning that a copy of
693: ** the string is made into memory obtained from sqlite3_malloc().
694: ** A value of n==0 means copy bytes of zP4 up to and including the
695: ** first null byte. If n>0 then copy n+1 bytes of zP4.
696: **
697: ** If n==P4_KEYINFO it means that zP4 is a pointer to a KeyInfo structure.
698: ** A copy is made of the KeyInfo structure into memory obtained from
699: ** sqlite3_malloc, to be freed when the Vdbe is finalized.
700: ** n==P4_KEYINFO_HANDOFF indicates that zP4 points to a KeyInfo structure
701: ** stored in memory that the caller has obtained from sqlite3_malloc. The
702: ** caller should not free the allocation, it will be freed when the Vdbe is
703: ** finalized.
704: **
705: ** Other values of n (P4_STATIC, P4_COLLSEQ etc.) indicate that zP4 points
706: ** to a string or structure that is guaranteed to exist for the lifetime of
707: ** the Vdbe. In these cases we can just copy the pointer.
708: **
709: ** If addr<0 then change P4 on the most recently inserted instruction.
710: */
711: void sqlite3VdbeChangeP4(Vdbe *p, int addr, const char *zP4, int n){
712: Op *pOp;
713: sqlite3 *db;
714: assert( p!=0 );
715: db = p->db;
716: assert( p->magic==VDBE_MAGIC_INIT );
717: if( p->aOp==0 || db->mallocFailed ){
718: if ( n!=P4_KEYINFO && n!=P4_VTAB ) {
719: freeP4(db, n, (void*)*(char**)&zP4);
720: }
721: return;
722: }
723: assert( p->nOp>0 );
724: assert( addr<p->nOp );
725: if( addr<0 ){
726: addr = p->nOp - 1;
727: }
728: pOp = &p->aOp[addr];
729: freeP4(db, pOp->p4type, pOp->p4.p);
730: pOp->p4.p = 0;
731: if( n==P4_INT32 ){
732: /* Note: this cast is safe, because the origin data point was an int
733: ** that was cast to a (const char *). */
734: pOp->p4.i = SQLITE_PTR_TO_INT(zP4);
735: pOp->p4type = P4_INT32;
736: }else if( zP4==0 ){
737: pOp->p4.p = 0;
738: pOp->p4type = P4_NOTUSED;
739: }else if( n==P4_KEYINFO ){
740: KeyInfo *pKeyInfo;
741: int nField, nByte;
742:
743: nField = ((KeyInfo*)zP4)->nField;
744: nByte = sizeof(*pKeyInfo) + (nField-1)*sizeof(pKeyInfo->aColl[0]) + nField;
745: pKeyInfo = sqlite3DbMallocRaw(0, nByte);
746: pOp->p4.pKeyInfo = pKeyInfo;
747: if( pKeyInfo ){
748: u8 *aSortOrder;
749: memcpy((char*)pKeyInfo, zP4, nByte - nField);
750: aSortOrder = pKeyInfo->aSortOrder;
751: if( aSortOrder ){
752: pKeyInfo->aSortOrder = (unsigned char*)&pKeyInfo->aColl[nField];
753: memcpy(pKeyInfo->aSortOrder, aSortOrder, nField);
754: }
755: pOp->p4type = P4_KEYINFO;
756: }else{
757: p->db->mallocFailed = 1;
758: pOp->p4type = P4_NOTUSED;
759: }
760: }else if( n==P4_KEYINFO_HANDOFF ){
761: pOp->p4.p = (void*)zP4;
762: pOp->p4type = P4_KEYINFO;
763: }else if( n==P4_VTAB ){
764: pOp->p4.p = (void*)zP4;
765: pOp->p4type = P4_VTAB;
766: sqlite3VtabLock((VTable *)zP4);
767: assert( ((VTable *)zP4)->db==p->db );
768: }else if( n<0 ){
769: pOp->p4.p = (void*)zP4;
770: pOp->p4type = (signed char)n;
771: }else{
772: if( n==0 ) n = sqlite3Strlen30(zP4);
773: pOp->p4.z = sqlite3DbStrNDup(p->db, zP4, n);
774: pOp->p4type = P4_DYNAMIC;
775: }
776: }
777:
778: #ifndef NDEBUG
779: /*
780: ** Change the comment on the the most recently coded instruction. Or
781: ** insert a No-op and add the comment to that new instruction. This
782: ** makes the code easier to read during debugging. None of this happens
783: ** in a production build.
784: */
785: static void vdbeVComment(Vdbe *p, const char *zFormat, va_list ap){
786: assert( p->nOp>0 || p->aOp==0 );
787: assert( p->aOp==0 || p->aOp[p->nOp-1].zComment==0 || p->db->mallocFailed );
788: if( p->nOp ){
789: assert( p->aOp );
790: sqlite3DbFree(p->db, p->aOp[p->nOp-1].zComment);
791: p->aOp[p->nOp-1].zComment = sqlite3VMPrintf(p->db, zFormat, ap);
792: }
793: }
794: void sqlite3VdbeComment(Vdbe *p, const char *zFormat, ...){
795: va_list ap;
796: if( p ){
797: va_start(ap, zFormat);
798: vdbeVComment(p, zFormat, ap);
799: va_end(ap);
800: }
801: }
802: void sqlite3VdbeNoopComment(Vdbe *p, const char *zFormat, ...){
803: va_list ap;
804: if( p ){
805: sqlite3VdbeAddOp0(p, OP_Noop);
806: va_start(ap, zFormat);
807: vdbeVComment(p, zFormat, ap);
808: va_end(ap);
809: }
810: }
811: #endif /* NDEBUG */
812:
813: /*
814: ** Return the opcode for a given address. If the address is -1, then
815: ** return the most recently inserted opcode.
816: **
817: ** If a memory allocation error has occurred prior to the calling of this
818: ** routine, then a pointer to a dummy VdbeOp will be returned. That opcode
819: ** is readable but not writable, though it is cast to a writable value.
820: ** The return of a dummy opcode allows the call to continue functioning
821: ** after a OOM fault without having to check to see if the return from
822: ** this routine is a valid pointer. But because the dummy.opcode is 0,
823: ** dummy will never be written to. This is verified by code inspection and
824: ** by running with Valgrind.
825: **
826: ** About the #ifdef SQLITE_OMIT_TRACE: Normally, this routine is never called
827: ** unless p->nOp>0. This is because in the absense of SQLITE_OMIT_TRACE,
828: ** an OP_Trace instruction is always inserted by sqlite3VdbeGet() as soon as
829: ** a new VDBE is created. So we are free to set addr to p->nOp-1 without
830: ** having to double-check to make sure that the result is non-negative. But
831: ** if SQLITE_OMIT_TRACE is defined, the OP_Trace is omitted and we do need to
832: ** check the value of p->nOp-1 before continuing.
833: */
834: VdbeOp *sqlite3VdbeGetOp(Vdbe *p, int addr){
835: /* C89 specifies that the constant "dummy" will be initialized to all
836: ** zeros, which is correct. MSVC generates a warning, nevertheless. */
837: static VdbeOp dummy; /* Ignore the MSVC warning about no initializer */
838: assert( p->magic==VDBE_MAGIC_INIT );
839: if( addr<0 ){
840: #ifdef SQLITE_OMIT_TRACE
841: if( p->nOp==0 ) return (VdbeOp*)&dummy;
842: #endif
843: addr = p->nOp - 1;
844: }
845: assert( (addr>=0 && addr<p->nOp) || p->db->mallocFailed );
846: if( p->db->mallocFailed ){
847: return (VdbeOp*)&dummy;
848: }else{
849: return &p->aOp[addr];
850: }
851: }
852:
853: #if !defined(SQLITE_OMIT_EXPLAIN) || !defined(NDEBUG) \
854: || defined(VDBE_PROFILE) || defined(SQLITE_DEBUG)
855: /*
856: ** Compute a string that describes the P4 parameter for an opcode.
857: ** Use zTemp for any required temporary buffer space.
858: */
859: static char *displayP4(Op *pOp, char *zTemp, int nTemp){
860: char *zP4 = zTemp;
861: assert( nTemp>=20 );
862: switch( pOp->p4type ){
863: case P4_KEYINFO_STATIC:
864: case P4_KEYINFO: {
865: int i, j;
866: KeyInfo *pKeyInfo = pOp->p4.pKeyInfo;
867: sqlite3_snprintf(nTemp, zTemp, "keyinfo(%d", pKeyInfo->nField);
868: i = sqlite3Strlen30(zTemp);
869: for(j=0; j<pKeyInfo->nField; j++){
870: CollSeq *pColl = pKeyInfo->aColl[j];
871: if( pColl ){
872: int n = sqlite3Strlen30(pColl->zName);
873: if( i+n>nTemp-6 ){
874: memcpy(&zTemp[i],",...",4);
875: break;
876: }
877: zTemp[i++] = ',';
878: if( pKeyInfo->aSortOrder && pKeyInfo->aSortOrder[j] ){
879: zTemp[i++] = '-';
880: }
881: memcpy(&zTemp[i], pColl->zName,n+1);
882: i += n;
883: }else if( i+4<nTemp-6 ){
884: memcpy(&zTemp[i],",nil",4);
885: i += 4;
886: }
887: }
888: zTemp[i++] = ')';
889: zTemp[i] = 0;
890: assert( i<nTemp );
891: break;
892: }
893: case P4_COLLSEQ: {
894: CollSeq *pColl = pOp->p4.pColl;
895: sqlite3_snprintf(nTemp, zTemp, "collseq(%.20s)", pColl->zName);
896: break;
897: }
898: case P4_FUNCDEF: {
899: FuncDef *pDef = pOp->p4.pFunc;
900: sqlite3_snprintf(nTemp, zTemp, "%s(%d)", pDef->zName, pDef->nArg);
901: break;
902: }
903: case P4_INT64: {
904: sqlite3_snprintf(nTemp, zTemp, "%lld", *pOp->p4.pI64);
905: break;
906: }
907: case P4_INT32: {
908: sqlite3_snprintf(nTemp, zTemp, "%d", pOp->p4.i);
909: break;
910: }
911: case P4_REAL: {
912: sqlite3_snprintf(nTemp, zTemp, "%.16g", *pOp->p4.pReal);
913: break;
914: }
915: case P4_MEM: {
916: Mem *pMem = pOp->p4.pMem;
917: if( pMem->flags & MEM_Str ){
918: zP4 = pMem->z;
919: }else if( pMem->flags & MEM_Int ){
920: sqlite3_snprintf(nTemp, zTemp, "%lld", pMem->u.i);
921: }else if( pMem->flags & MEM_Real ){
922: sqlite3_snprintf(nTemp, zTemp, "%.16g", pMem->r);
923: }else if( pMem->flags & MEM_Null ){
924: sqlite3_snprintf(nTemp, zTemp, "NULL");
925: }else{
926: assert( pMem->flags & MEM_Blob );
927: zP4 = "(blob)";
928: }
929: break;
930: }
931: #ifndef SQLITE_OMIT_VIRTUALTABLE
932: case P4_VTAB: {
933: sqlite3_vtab *pVtab = pOp->p4.pVtab->pVtab;
934: sqlite3_snprintf(nTemp, zTemp, "vtab:%p:%p", pVtab, pVtab->pModule);
935: break;
936: }
937: #endif
938: case P4_INTARRAY: {
939: sqlite3_snprintf(nTemp, zTemp, "intarray");
940: break;
941: }
942: case P4_SUBPROGRAM: {
943: sqlite3_snprintf(nTemp, zTemp, "program");
944: break;
945: }
946: case P4_ADVANCE: {
947: zTemp[0] = 0;
948: break;
949: }
950: default: {
951: zP4 = pOp->p4.z;
952: if( zP4==0 ){
953: zP4 = zTemp;
954: zTemp[0] = 0;
955: }
956: }
957: }
958: assert( zP4!=0 );
959: return zP4;
960: }
961: #endif
962:
963: /*
964: ** Declare to the Vdbe that the BTree object at db->aDb[i] is used.
965: **
966: ** The prepared statements need to know in advance the complete set of
967: ** attached databases that will be use. A mask of these databases
968: ** is maintained in p->btreeMask. The p->lockMask value is the subset of
969: ** p->btreeMask of databases that will require a lock.
970: */
971: void sqlite3VdbeUsesBtree(Vdbe *p, int i){
972: assert( i>=0 && i<p->db->nDb && i<(int)sizeof(yDbMask)*8 );
973: assert( i<(int)sizeof(p->btreeMask)*8 );
974: p->btreeMask |= ((yDbMask)1)<<i;
975: if( i!=1 && sqlite3BtreeSharable(p->db->aDb[i].pBt) ){
976: p->lockMask |= ((yDbMask)1)<<i;
977: }
978: }
979:
980: #if !defined(SQLITE_OMIT_SHARED_CACHE) && SQLITE_THREADSAFE>0
981: /*
982: ** If SQLite is compiled to support shared-cache mode and to be threadsafe,
983: ** this routine obtains the mutex associated with each BtShared structure
984: ** that may be accessed by the VM passed as an argument. In doing so it also
985: ** sets the BtShared.db member of each of the BtShared structures, ensuring
986: ** that the correct busy-handler callback is invoked if required.
987: **
988: ** If SQLite is not threadsafe but does support shared-cache mode, then
989: ** sqlite3BtreeEnter() is invoked to set the BtShared.db variables
990: ** of all of BtShared structures accessible via the database handle
991: ** associated with the VM.
992: **
993: ** If SQLite is not threadsafe and does not support shared-cache mode, this
994: ** function is a no-op.
995: **
996: ** The p->btreeMask field is a bitmask of all btrees that the prepared
997: ** statement p will ever use. Let N be the number of bits in p->btreeMask
998: ** corresponding to btrees that use shared cache. Then the runtime of
999: ** this routine is N*N. But as N is rarely more than 1, this should not
1000: ** be a problem.
1001: */
1002: void sqlite3VdbeEnter(Vdbe *p){
1003: int i;
1004: yDbMask mask;
1005: sqlite3 *db;
1006: Db *aDb;
1007: int nDb;
1008: if( p->lockMask==0 ) return; /* The common case */
1009: db = p->db;
1010: aDb = db->aDb;
1011: nDb = db->nDb;
1012: for(i=0, mask=1; i<nDb; i++, mask += mask){
1013: if( i!=1 && (mask & p->lockMask)!=0 && ALWAYS(aDb[i].pBt!=0) ){
1014: sqlite3BtreeEnter(aDb[i].pBt);
1015: }
1016: }
1017: }
1018: #endif
1019:
1020: #if !defined(SQLITE_OMIT_SHARED_CACHE) && SQLITE_THREADSAFE>0
1021: /*
1022: ** Unlock all of the btrees previously locked by a call to sqlite3VdbeEnter().
1023: */
1024: void sqlite3VdbeLeave(Vdbe *p){
1025: int i;
1026: yDbMask mask;
1027: sqlite3 *db;
1028: Db *aDb;
1029: int nDb;
1030: if( p->lockMask==0 ) return; /* The common case */
1031: db = p->db;
1032: aDb = db->aDb;
1033: nDb = db->nDb;
1034: for(i=0, mask=1; i<nDb; i++, mask += mask){
1035: if( i!=1 && (mask & p->lockMask)!=0 && ALWAYS(aDb[i].pBt!=0) ){
1036: sqlite3BtreeLeave(aDb[i].pBt);
1037: }
1038: }
1039: }
1040: #endif
1041:
1042: #if defined(VDBE_PROFILE) || defined(SQLITE_DEBUG)
1043: /*
1044: ** Print a single opcode. This routine is used for debugging only.
1045: */
1046: void sqlite3VdbePrintOp(FILE *pOut, int pc, Op *pOp){
1047: char *zP4;
1048: char zPtr[50];
1049: static const char *zFormat1 = "%4d %-13s %4d %4d %4d %-4s %.2X %s\n";
1050: if( pOut==0 ) pOut = stdout;
1051: zP4 = displayP4(pOp, zPtr, sizeof(zPtr));
1052: fprintf(pOut, zFormat1, pc,
1053: sqlite3OpcodeName(pOp->opcode), pOp->p1, pOp->p2, pOp->p3, zP4, pOp->p5,
1054: #ifdef SQLITE_DEBUG
1055: pOp->zComment ? pOp->zComment : ""
1056: #else
1057: ""
1058: #endif
1059: );
1060: fflush(pOut);
1061: }
1062: #endif
1063:
1064: /*
1065: ** Release an array of N Mem elements
1066: */
1067: static void releaseMemArray(Mem *p, int N){
1068: if( p && N ){
1069: Mem *pEnd;
1070: sqlite3 *db = p->db;
1071: u8 malloc_failed = db->mallocFailed;
1072: if( db->pnBytesFreed ){
1073: for(pEnd=&p[N]; p<pEnd; p++){
1074: sqlite3DbFree(db, p->zMalloc);
1075: }
1076: return;
1077: }
1078: for(pEnd=&p[N]; p<pEnd; p++){
1079: assert( (&p[1])==pEnd || p[0].db==p[1].db );
1080:
1081: /* This block is really an inlined version of sqlite3VdbeMemRelease()
1082: ** that takes advantage of the fact that the memory cell value is
1083: ** being set to NULL after releasing any dynamic resources.
1084: **
1085: ** The justification for duplicating code is that according to
1086: ** callgrind, this causes a certain test case to hit the CPU 4.7
1087: ** percent less (x86 linux, gcc version 4.1.2, -O6) than if
1088: ** sqlite3MemRelease() were called from here. With -O2, this jumps
1089: ** to 6.6 percent. The test case is inserting 1000 rows into a table
1090: ** with no indexes using a single prepared INSERT statement, bind()
1091: ** and reset(). Inserts are grouped into a transaction.
1092: */
1093: if( p->flags&(MEM_Agg|MEM_Dyn|MEM_Frame|MEM_RowSet) ){
1094: sqlite3VdbeMemRelease(p);
1095: }else if( p->zMalloc ){
1096: sqlite3DbFree(db, p->zMalloc);
1097: p->zMalloc = 0;
1098: }
1099:
1100: p->flags = MEM_Invalid;
1101: }
1102: db->mallocFailed = malloc_failed;
1103: }
1104: }
1105:
1106: /*
1107: ** Delete a VdbeFrame object and its contents. VdbeFrame objects are
1108: ** allocated by the OP_Program opcode in sqlite3VdbeExec().
1109: */
1110: void sqlite3VdbeFrameDelete(VdbeFrame *p){
1111: int i;
1112: Mem *aMem = VdbeFrameMem(p);
1113: VdbeCursor **apCsr = (VdbeCursor **)&aMem[p->nChildMem];
1114: for(i=0; i<p->nChildCsr; i++){
1115: sqlite3VdbeFreeCursor(p->v, apCsr[i]);
1116: }
1117: releaseMemArray(aMem, p->nChildMem);
1118: sqlite3DbFree(p->v->db, p);
1119: }
1120:
1121: #ifndef SQLITE_OMIT_EXPLAIN
1122: /*
1123: ** Give a listing of the program in the virtual machine.
1124: **
1125: ** The interface is the same as sqlite3VdbeExec(). But instead of
1126: ** running the code, it invokes the callback once for each instruction.
1127: ** This feature is used to implement "EXPLAIN".
1128: **
1129: ** When p->explain==1, each instruction is listed. When
1130: ** p->explain==2, only OP_Explain instructions are listed and these
1131: ** are shown in a different format. p->explain==2 is used to implement
1132: ** EXPLAIN QUERY PLAN.
1133: **
1134: ** When p->explain==1, first the main program is listed, then each of
1135: ** the trigger subprograms are listed one by one.
1136: */
1137: int sqlite3VdbeList(
1138: Vdbe *p /* The VDBE */
1139: ){
1140: int nRow; /* Stop when row count reaches this */
1141: int nSub = 0; /* Number of sub-vdbes seen so far */
1142: SubProgram **apSub = 0; /* Array of sub-vdbes */
1143: Mem *pSub = 0; /* Memory cell hold array of subprogs */
1144: sqlite3 *db = p->db; /* The database connection */
1145: int i; /* Loop counter */
1146: int rc = SQLITE_OK; /* Return code */
1147: Mem *pMem = &p->aMem[1]; /* First Mem of result set */
1148:
1149: assert( p->explain );
1150: assert( p->magic==VDBE_MAGIC_RUN );
1151: assert( p->rc==SQLITE_OK || p->rc==SQLITE_BUSY || p->rc==SQLITE_NOMEM );
1152:
1153: /* Even though this opcode does not use dynamic strings for
1154: ** the result, result columns may become dynamic if the user calls
1155: ** sqlite3_column_text16(), causing a translation to UTF-16 encoding.
1156: */
1157: releaseMemArray(pMem, 8);
1158: p->pResultSet = 0;
1159:
1160: if( p->rc==SQLITE_NOMEM ){
1161: /* This happens if a malloc() inside a call to sqlite3_column_text() or
1162: ** sqlite3_column_text16() failed. */
1163: db->mallocFailed = 1;
1164: return SQLITE_ERROR;
1165: }
1166:
1167: /* When the number of output rows reaches nRow, that means the
1168: ** listing has finished and sqlite3_step() should return SQLITE_DONE.
1169: ** nRow is the sum of the number of rows in the main program, plus
1170: ** the sum of the number of rows in all trigger subprograms encountered
1171: ** so far. The nRow value will increase as new trigger subprograms are
1172: ** encountered, but p->pc will eventually catch up to nRow.
1173: */
1174: nRow = p->nOp;
1175: if( p->explain==1 ){
1176: /* The first 8 memory cells are used for the result set. So we will
1177: ** commandeer the 9th cell to use as storage for an array of pointers
1178: ** to trigger subprograms. The VDBE is guaranteed to have at least 9
1179: ** cells. */
1180: assert( p->nMem>9 );
1181: pSub = &p->aMem[9];
1182: if( pSub->flags&MEM_Blob ){
1183: /* On the first call to sqlite3_step(), pSub will hold a NULL. It is
1184: ** initialized to a BLOB by the P4_SUBPROGRAM processing logic below */
1185: nSub = pSub->n/sizeof(Vdbe*);
1186: apSub = (SubProgram **)pSub->z;
1187: }
1188: for(i=0; i<nSub; i++){
1189: nRow += apSub[i]->nOp;
1190: }
1191: }
1192:
1193: do{
1194: i = p->pc++;
1195: }while( i<nRow && p->explain==2 && p->aOp[i].opcode!=OP_Explain );
1196: if( i>=nRow ){
1197: p->rc = SQLITE_OK;
1198: rc = SQLITE_DONE;
1199: }else if( db->u1.isInterrupted ){
1200: p->rc = SQLITE_INTERRUPT;
1201: rc = SQLITE_ERROR;
1202: sqlite3SetString(&p->zErrMsg, db, "%s", sqlite3ErrStr(p->rc));
1203: }else{
1204: char *z;
1205: Op *pOp;
1206: if( i<p->nOp ){
1207: /* The output line number is small enough that we are still in the
1208: ** main program. */
1209: pOp = &p->aOp[i];
1210: }else{
1211: /* We are currently listing subprograms. Figure out which one and
1212: ** pick up the appropriate opcode. */
1213: int j;
1214: i -= p->nOp;
1215: for(j=0; i>=apSub[j]->nOp; j++){
1216: i -= apSub[j]->nOp;
1217: }
1218: pOp = &apSub[j]->aOp[i];
1219: }
1220: if( p->explain==1 ){
1221: pMem->flags = MEM_Int;
1222: pMem->type = SQLITE_INTEGER;
1223: pMem->u.i = i; /* Program counter */
1224: pMem++;
1225:
1226: pMem->flags = MEM_Static|MEM_Str|MEM_Term;
1227: pMem->z = (char*)sqlite3OpcodeName(pOp->opcode); /* Opcode */
1228: assert( pMem->z!=0 );
1229: pMem->n = sqlite3Strlen30(pMem->z);
1230: pMem->type = SQLITE_TEXT;
1231: pMem->enc = SQLITE_UTF8;
1232: pMem++;
1233:
1234: /* When an OP_Program opcode is encounter (the only opcode that has
1235: ** a P4_SUBPROGRAM argument), expand the size of the array of subprograms
1236: ** kept in p->aMem[9].z to hold the new program - assuming this subprogram
1237: ** has not already been seen.
1238: */
1239: if( pOp->p4type==P4_SUBPROGRAM ){
1240: int nByte = (nSub+1)*sizeof(SubProgram*);
1241: int j;
1242: for(j=0; j<nSub; j++){
1243: if( apSub[j]==pOp->p4.pProgram ) break;
1244: }
1245: if( j==nSub && SQLITE_OK==sqlite3VdbeMemGrow(pSub, nByte, 1) ){
1246: apSub = (SubProgram **)pSub->z;
1247: apSub[nSub++] = pOp->p4.pProgram;
1248: pSub->flags |= MEM_Blob;
1249: pSub->n = nSub*sizeof(SubProgram*);
1250: }
1251: }
1252: }
1253:
1254: pMem->flags = MEM_Int;
1255: pMem->u.i = pOp->p1; /* P1 */
1256: pMem->type = SQLITE_INTEGER;
1257: pMem++;
1258:
1259: pMem->flags = MEM_Int;
1260: pMem->u.i = pOp->p2; /* P2 */
1261: pMem->type = SQLITE_INTEGER;
1262: pMem++;
1263:
1264: pMem->flags = MEM_Int;
1265: pMem->u.i = pOp->p3; /* P3 */
1266: pMem->type = SQLITE_INTEGER;
1267: pMem++;
1268:
1269: if( sqlite3VdbeMemGrow(pMem, 32, 0) ){ /* P4 */
1270: assert( p->db->mallocFailed );
1271: return SQLITE_ERROR;
1272: }
1273: pMem->flags = MEM_Dyn|MEM_Str|MEM_Term;
1274: z = displayP4(pOp, pMem->z, 32);
1275: if( z!=pMem->z ){
1276: sqlite3VdbeMemSetStr(pMem, z, -1, SQLITE_UTF8, 0);
1277: }else{
1278: assert( pMem->z!=0 );
1279: pMem->n = sqlite3Strlen30(pMem->z);
1280: pMem->enc = SQLITE_UTF8;
1281: }
1282: pMem->type = SQLITE_TEXT;
1283: pMem++;
1284:
1285: if( p->explain==1 ){
1286: if( sqlite3VdbeMemGrow(pMem, 4, 0) ){
1287: assert( p->db->mallocFailed );
1288: return SQLITE_ERROR;
1289: }
1290: pMem->flags = MEM_Dyn|MEM_Str|MEM_Term;
1291: pMem->n = 2;
1292: sqlite3_snprintf(3, pMem->z, "%.2x", pOp->p5); /* P5 */
1293: pMem->type = SQLITE_TEXT;
1294: pMem->enc = SQLITE_UTF8;
1295: pMem++;
1296:
1297: #ifdef SQLITE_DEBUG
1298: if( pOp->zComment ){
1299: pMem->flags = MEM_Str|MEM_Term;
1300: pMem->z = pOp->zComment;
1301: pMem->n = sqlite3Strlen30(pMem->z);
1302: pMem->enc = SQLITE_UTF8;
1303: pMem->type = SQLITE_TEXT;
1304: }else
1305: #endif
1306: {
1307: pMem->flags = MEM_Null; /* Comment */
1308: pMem->type = SQLITE_NULL;
1309: }
1310: }
1311:
1312: p->nResColumn = 8 - 4*(p->explain-1);
1313: p->pResultSet = &p->aMem[1];
1314: p->rc = SQLITE_OK;
1315: rc = SQLITE_ROW;
1316: }
1317: return rc;
1318: }
1319: #endif /* SQLITE_OMIT_EXPLAIN */
1320:
1321: #ifdef SQLITE_DEBUG
1322: /*
1323: ** Print the SQL that was used to generate a VDBE program.
1324: */
1325: void sqlite3VdbePrintSql(Vdbe *p){
1326: int nOp = p->nOp;
1327: VdbeOp *pOp;
1328: if( nOp<1 ) return;
1329: pOp = &p->aOp[0];
1330: if( pOp->opcode==OP_Trace && pOp->p4.z!=0 ){
1331: const char *z = pOp->p4.z;
1332: while( sqlite3Isspace(*z) ) z++;
1333: printf("SQL: [%s]\n", z);
1334: }
1335: }
1336: #endif
1337:
1338: #if !defined(SQLITE_OMIT_TRACE) && defined(SQLITE_ENABLE_IOTRACE)
1339: /*
1340: ** Print an IOTRACE message showing SQL content.
1341: */
1342: void sqlite3VdbeIOTraceSql(Vdbe *p){
1343: int nOp = p->nOp;
1344: VdbeOp *pOp;
1345: if( sqlite3IoTrace==0 ) return;
1346: if( nOp<1 ) return;
1347: pOp = &p->aOp[0];
1348: if( pOp->opcode==OP_Trace && pOp->p4.z!=0 ){
1349: int i, j;
1350: char z[1000];
1351: sqlite3_snprintf(sizeof(z), z, "%s", pOp->p4.z);
1352: for(i=0; sqlite3Isspace(z[i]); i++){}
1353: for(j=0; z[i]; i++){
1354: if( sqlite3Isspace(z[i]) ){
1355: if( z[i-1]!=' ' ){
1356: z[j++] = ' ';
1357: }
1358: }else{
1359: z[j++] = z[i];
1360: }
1361: }
1362: z[j] = 0;
1363: sqlite3IoTrace("SQL %s\n", z);
1364: }
1365: }
1366: #endif /* !SQLITE_OMIT_TRACE && SQLITE_ENABLE_IOTRACE */
1367:
1368: /*
1369: ** Allocate space from a fixed size buffer and return a pointer to
1370: ** that space. If insufficient space is available, return NULL.
1371: **
1372: ** The pBuf parameter is the initial value of a pointer which will
1373: ** receive the new memory. pBuf is normally NULL. If pBuf is not
1374: ** NULL, it means that memory space has already been allocated and that
1375: ** this routine should not allocate any new memory. When pBuf is not
1376: ** NULL simply return pBuf. Only allocate new memory space when pBuf
1377: ** is NULL.
1378: **
1379: ** nByte is the number of bytes of space needed.
1380: **
1381: ** *ppFrom points to available space and pEnd points to the end of the
1382: ** available space. When space is allocated, *ppFrom is advanced past
1383: ** the end of the allocated space.
1384: **
1385: ** *pnByte is a counter of the number of bytes of space that have failed
1386: ** to allocate. If there is insufficient space in *ppFrom to satisfy the
1387: ** request, then increment *pnByte by the amount of the request.
1388: */
1389: static void *allocSpace(
1390: void *pBuf, /* Where return pointer will be stored */
1391: int nByte, /* Number of bytes to allocate */
1392: u8 **ppFrom, /* IN/OUT: Allocate from *ppFrom */
1393: u8 *pEnd, /* Pointer to 1 byte past the end of *ppFrom buffer */
1394: int *pnByte /* If allocation cannot be made, increment *pnByte */
1395: ){
1396: assert( EIGHT_BYTE_ALIGNMENT(*ppFrom) );
1397: if( pBuf ) return pBuf;
1398: nByte = ROUND8(nByte);
1399: if( &(*ppFrom)[nByte] <= pEnd ){
1400: pBuf = (void*)*ppFrom;
1401: *ppFrom += nByte;
1402: }else{
1403: *pnByte += nByte;
1404: }
1405: return pBuf;
1406: }
1407:
1408: /*
1409: ** Rewind the VDBE back to the beginning in preparation for
1410: ** running it.
1411: */
1412: void sqlite3VdbeRewind(Vdbe *p){
1413: #if defined(SQLITE_DEBUG) || defined(VDBE_PROFILE)
1414: int i;
1415: #endif
1416: assert( p!=0 );
1417: assert( p->magic==VDBE_MAGIC_INIT );
1418:
1419: /* There should be at least one opcode.
1420: */
1421: assert( p->nOp>0 );
1422:
1423: /* Set the magic to VDBE_MAGIC_RUN sooner rather than later. */
1424: p->magic = VDBE_MAGIC_RUN;
1425:
1426: #ifdef SQLITE_DEBUG
1427: for(i=1; i<p->nMem; i++){
1428: assert( p->aMem[i].db==p->db );
1429: }
1430: #endif
1431: p->pc = -1;
1432: p->rc = SQLITE_OK;
1433: p->errorAction = OE_Abort;
1434: p->magic = VDBE_MAGIC_RUN;
1435: p->nChange = 0;
1436: p->cacheCtr = 1;
1437: p->minWriteFileFormat = 255;
1438: p->iStatement = 0;
1439: p->nFkConstraint = 0;
1440: #ifdef VDBE_PROFILE
1441: for(i=0; i<p->nOp; i++){
1442: p->aOp[i].cnt = 0;
1443: p->aOp[i].cycles = 0;
1444: }
1445: #endif
1446: }
1447:
1448: /*
1449: ** Prepare a virtual machine for execution for the first time after
1450: ** creating the virtual machine. This involves things such
1451: ** as allocating stack space and initializing the program counter.
1452: ** After the VDBE has be prepped, it can be executed by one or more
1453: ** calls to sqlite3VdbeExec().
1454: **
1455: ** This function may be called exact once on a each virtual machine.
1456: ** After this routine is called the VM has been "packaged" and is ready
1457: ** to run. After this routine is called, futher calls to
1458: ** sqlite3VdbeAddOp() functions are prohibited. This routine disconnects
1459: ** the Vdbe from the Parse object that helped generate it so that the
1460: ** the Vdbe becomes an independent entity and the Parse object can be
1461: ** destroyed.
1462: **
1463: ** Use the sqlite3VdbeRewind() procedure to restore a virtual machine back
1464: ** to its initial state after it has been run.
1465: */
1466: void sqlite3VdbeMakeReady(
1467: Vdbe *p, /* The VDBE */
1468: Parse *pParse /* Parsing context */
1469: ){
1470: sqlite3 *db; /* The database connection */
1471: int nVar; /* Number of parameters */
1472: int nMem; /* Number of VM memory registers */
1473: int nCursor; /* Number of cursors required */
1474: int nArg; /* Number of arguments in subprograms */
1475: int nOnce; /* Number of OP_Once instructions */
1476: int n; /* Loop counter */
1477: u8 *zCsr; /* Memory available for allocation */
1478: u8 *zEnd; /* First byte past allocated memory */
1479: int nByte; /* How much extra memory is needed */
1480:
1481: assert( p!=0 );
1482: assert( p->nOp>0 );
1483: assert( pParse!=0 );
1484: assert( p->magic==VDBE_MAGIC_INIT );
1485: db = p->db;
1486: assert( db->mallocFailed==0 );
1487: nVar = pParse->nVar;
1488: nMem = pParse->nMem;
1489: nCursor = pParse->nTab;
1490: nArg = pParse->nMaxArg;
1491: nOnce = pParse->nOnce;
1492: if( nOnce==0 ) nOnce = 1; /* Ensure at least one byte in p->aOnceFlag[] */
1493:
1494: /* For each cursor required, also allocate a memory cell. Memory
1495: ** cells (nMem+1-nCursor)..nMem, inclusive, will never be used by
1496: ** the vdbe program. Instead they are used to allocate space for
1497: ** VdbeCursor/BtCursor structures. The blob of memory associated with
1498: ** cursor 0 is stored in memory cell nMem. Memory cell (nMem-1)
1499: ** stores the blob of memory associated with cursor 1, etc.
1500: **
1501: ** See also: allocateCursor().
1502: */
1503: nMem += nCursor;
1504:
1505: /* Allocate space for memory registers, SQL variables, VDBE cursors and
1506: ** an array to marshal SQL function arguments in.
1507: */
1508: zCsr = (u8*)&p->aOp[p->nOp]; /* Memory avaliable for allocation */
1509: zEnd = (u8*)&p->aOp[p->nOpAlloc]; /* First byte past end of zCsr[] */
1510:
1511: resolveP2Values(p, &nArg);
1512: p->usesStmtJournal = (u8)(pParse->isMultiWrite && pParse->mayAbort);
1513: if( pParse->explain && nMem<10 ){
1514: nMem = 10;
1515: }
1516: memset(zCsr, 0, zEnd-zCsr);
1517: zCsr += (zCsr - (u8*)0)&7;
1518: assert( EIGHT_BYTE_ALIGNMENT(zCsr) );
1519: p->expired = 0;
1520:
1521: /* Memory for registers, parameters, cursor, etc, is allocated in two
1522: ** passes. On the first pass, we try to reuse unused space at the
1523: ** end of the opcode array. If we are unable to satisfy all memory
1524: ** requirements by reusing the opcode array tail, then the second
1525: ** pass will fill in the rest using a fresh allocation.
1526: **
1527: ** This two-pass approach that reuses as much memory as possible from
1528: ** the leftover space at the end of the opcode array can significantly
1529: ** reduce the amount of memory held by a prepared statement.
1530: */
1531: do {
1532: nByte = 0;
1533: p->aMem = allocSpace(p->aMem, nMem*sizeof(Mem), &zCsr, zEnd, &nByte);
1534: p->aVar = allocSpace(p->aVar, nVar*sizeof(Mem), &zCsr, zEnd, &nByte);
1535: p->apArg = allocSpace(p->apArg, nArg*sizeof(Mem*), &zCsr, zEnd, &nByte);
1536: p->azVar = allocSpace(p->azVar, nVar*sizeof(char*), &zCsr, zEnd, &nByte);
1537: p->apCsr = allocSpace(p->apCsr, nCursor*sizeof(VdbeCursor*),
1538: &zCsr, zEnd, &nByte);
1539: p->aOnceFlag = allocSpace(p->aOnceFlag, nOnce, &zCsr, zEnd, &nByte);
1540: if( nByte ){
1541: p->pFree = sqlite3DbMallocZero(db, nByte);
1542: }
1543: zCsr = p->pFree;
1544: zEnd = &zCsr[nByte];
1545: }while( nByte && !db->mallocFailed );
1546:
1547: p->nCursor = (u16)nCursor;
1548: p->nOnceFlag = nOnce;
1549: if( p->aVar ){
1550: p->nVar = (ynVar)nVar;
1551: for(n=0; n<nVar; n++){
1552: p->aVar[n].flags = MEM_Null;
1553: p->aVar[n].db = db;
1554: }
1555: }
1556: if( p->azVar ){
1557: p->nzVar = pParse->nzVar;
1558: memcpy(p->azVar, pParse->azVar, p->nzVar*sizeof(p->azVar[0]));
1559: memset(pParse->azVar, 0, pParse->nzVar*sizeof(pParse->azVar[0]));
1560: }
1561: if( p->aMem ){
1562: p->aMem--; /* aMem[] goes from 1..nMem */
1563: p->nMem = nMem; /* not from 0..nMem-1 */
1564: for(n=1; n<=nMem; n++){
1565: p->aMem[n].flags = MEM_Invalid;
1566: p->aMem[n].db = db;
1567: }
1568: }
1569: p->explain = pParse->explain;
1570: sqlite3VdbeRewind(p);
1571: }
1572:
1573: /*
1574: ** Close a VDBE cursor and release all the resources that cursor
1575: ** happens to hold.
1576: */
1577: void sqlite3VdbeFreeCursor(Vdbe *p, VdbeCursor *pCx){
1578: if( pCx==0 ){
1579: return;
1580: }
1581: sqlite3VdbeSorterClose(p->db, pCx);
1582: if( pCx->pBt ){
1583: sqlite3BtreeClose(pCx->pBt);
1584: /* The pCx->pCursor will be close automatically, if it exists, by
1585: ** the call above. */
1586: }else if( pCx->pCursor ){
1587: sqlite3BtreeCloseCursor(pCx->pCursor);
1588: }
1589: #ifndef SQLITE_OMIT_VIRTUALTABLE
1590: if( pCx->pVtabCursor ){
1591: sqlite3_vtab_cursor *pVtabCursor = pCx->pVtabCursor;
1592: const sqlite3_module *pModule = pCx->pModule;
1593: p->inVtabMethod = 1;
1594: pModule->xClose(pVtabCursor);
1595: p->inVtabMethod = 0;
1596: }
1597: #endif
1598: }
1599:
1600: /*
1601: ** Copy the values stored in the VdbeFrame structure to its Vdbe. This
1602: ** is used, for example, when a trigger sub-program is halted to restore
1603: ** control to the main program.
1604: */
1605: int sqlite3VdbeFrameRestore(VdbeFrame *pFrame){
1606: Vdbe *v = pFrame->v;
1607: v->aOnceFlag = pFrame->aOnceFlag;
1608: v->nOnceFlag = pFrame->nOnceFlag;
1609: v->aOp = pFrame->aOp;
1610: v->nOp = pFrame->nOp;
1611: v->aMem = pFrame->aMem;
1612: v->nMem = pFrame->nMem;
1613: v->apCsr = pFrame->apCsr;
1614: v->nCursor = pFrame->nCursor;
1615: v->db->lastRowid = pFrame->lastRowid;
1616: v->nChange = pFrame->nChange;
1617: return pFrame->pc;
1618: }
1619:
1620: /*
1621: ** Close all cursors.
1622: **
1623: ** Also release any dynamic memory held by the VM in the Vdbe.aMem memory
1624: ** cell array. This is necessary as the memory cell array may contain
1625: ** pointers to VdbeFrame objects, which may in turn contain pointers to
1626: ** open cursors.
1627: */
1628: static void closeAllCursors(Vdbe *p){
1629: if( p->pFrame ){
1630: VdbeFrame *pFrame;
1631: for(pFrame=p->pFrame; pFrame->pParent; pFrame=pFrame->pParent);
1632: sqlite3VdbeFrameRestore(pFrame);
1633: }
1634: p->pFrame = 0;
1635: p->nFrame = 0;
1636:
1637: if( p->apCsr ){
1638: int i;
1639: for(i=0; i<p->nCursor; i++){
1640: VdbeCursor *pC = p->apCsr[i];
1641: if( pC ){
1642: sqlite3VdbeFreeCursor(p, pC);
1643: p->apCsr[i] = 0;
1644: }
1645: }
1646: }
1647: if( p->aMem ){
1648: releaseMemArray(&p->aMem[1], p->nMem);
1649: }
1650: while( p->pDelFrame ){
1651: VdbeFrame *pDel = p->pDelFrame;
1652: p->pDelFrame = pDel->pParent;
1653: sqlite3VdbeFrameDelete(pDel);
1654: }
1655: }
1656:
1657: /*
1658: ** Clean up the VM after execution.
1659: **
1660: ** This routine will automatically close any cursors, lists, and/or
1661: ** sorters that were left open. It also deletes the values of
1662: ** variables in the aVar[] array.
1663: */
1664: static void Cleanup(Vdbe *p){
1665: sqlite3 *db = p->db;
1666:
1667: #ifdef SQLITE_DEBUG
1668: /* Execute assert() statements to ensure that the Vdbe.apCsr[] and
1669: ** Vdbe.aMem[] arrays have already been cleaned up. */
1670: int i;
1671: if( p->apCsr ) for(i=0; i<p->nCursor; i++) assert( p->apCsr[i]==0 );
1672: if( p->aMem ){
1673: for(i=1; i<=p->nMem; i++) assert( p->aMem[i].flags==MEM_Invalid );
1674: }
1675: #endif
1676:
1677: sqlite3DbFree(db, p->zErrMsg);
1678: p->zErrMsg = 0;
1679: p->pResultSet = 0;
1680: }
1681:
1682: /*
1683: ** Set the number of result columns that will be returned by this SQL
1684: ** statement. This is now set at compile time, rather than during
1685: ** execution of the vdbe program so that sqlite3_column_count() can
1686: ** be called on an SQL statement before sqlite3_step().
1687: */
1688: void sqlite3VdbeSetNumCols(Vdbe *p, int nResColumn){
1689: Mem *pColName;
1690: int n;
1691: sqlite3 *db = p->db;
1692:
1693: releaseMemArray(p->aColName, p->nResColumn*COLNAME_N);
1694: sqlite3DbFree(db, p->aColName);
1695: n = nResColumn*COLNAME_N;
1696: p->nResColumn = (u16)nResColumn;
1697: p->aColName = pColName = (Mem*)sqlite3DbMallocZero(db, sizeof(Mem)*n );
1698: if( p->aColName==0 ) return;
1699: while( n-- > 0 ){
1700: pColName->flags = MEM_Null;
1701: pColName->db = p->db;
1702: pColName++;
1703: }
1704: }
1705:
1706: /*
1707: ** Set the name of the idx'th column to be returned by the SQL statement.
1708: ** zName must be a pointer to a nul terminated string.
1709: **
1710: ** This call must be made after a call to sqlite3VdbeSetNumCols().
1711: **
1712: ** The final parameter, xDel, must be one of SQLITE_DYNAMIC, SQLITE_STATIC
1713: ** or SQLITE_TRANSIENT. If it is SQLITE_DYNAMIC, then the buffer pointed
1714: ** to by zName will be freed by sqlite3DbFree() when the vdbe is destroyed.
1715: */
1716: int sqlite3VdbeSetColName(
1717: Vdbe *p, /* Vdbe being configured */
1718: int idx, /* Index of column zName applies to */
1719: int var, /* One of the COLNAME_* constants */
1720: const char *zName, /* Pointer to buffer containing name */
1721: void (*xDel)(void*) /* Memory management strategy for zName */
1722: ){
1723: int rc;
1724: Mem *pColName;
1725: assert( idx<p->nResColumn );
1726: assert( var<COLNAME_N );
1727: if( p->db->mallocFailed ){
1728: assert( !zName || xDel!=SQLITE_DYNAMIC );
1729: return SQLITE_NOMEM;
1730: }
1731: assert( p->aColName!=0 );
1732: pColName = &(p->aColName[idx+var*p->nResColumn]);
1733: rc = sqlite3VdbeMemSetStr(pColName, zName, -1, SQLITE_UTF8, xDel);
1734: assert( rc!=0 || !zName || (pColName->flags&MEM_Term)!=0 );
1735: return rc;
1736: }
1737:
1738: /*
1739: ** A read or write transaction may or may not be active on database handle
1740: ** db. If a transaction is active, commit it. If there is a
1741: ** write-transaction spanning more than one database file, this routine
1742: ** takes care of the master journal trickery.
1743: */
1744: static int vdbeCommit(sqlite3 *db, Vdbe *p){
1745: int i;
1746: int nTrans = 0; /* Number of databases with an active write-transaction */
1747: int rc = SQLITE_OK;
1748: int needXcommit = 0;
1749:
1750: #ifdef SQLITE_OMIT_VIRTUALTABLE
1751: /* With this option, sqlite3VtabSync() is defined to be simply
1752: ** SQLITE_OK so p is not used.
1753: */
1754: UNUSED_PARAMETER(p);
1755: #endif
1756:
1757: /* Before doing anything else, call the xSync() callback for any
1758: ** virtual module tables written in this transaction. This has to
1759: ** be done before determining whether a master journal file is
1760: ** required, as an xSync() callback may add an attached database
1761: ** to the transaction.
1762: */
1763: rc = sqlite3VtabSync(db, &p->zErrMsg);
1764:
1765: /* This loop determines (a) if the commit hook should be invoked and
1766: ** (b) how many database files have open write transactions, not
1767: ** including the temp database. (b) is important because if more than
1768: ** one database file has an open write transaction, a master journal
1769: ** file is required for an atomic commit.
1770: */
1771: for(i=0; rc==SQLITE_OK && i<db->nDb; i++){
1772: Btree *pBt = db->aDb[i].pBt;
1773: if( sqlite3BtreeIsInTrans(pBt) ){
1774: needXcommit = 1;
1775: if( i!=1 ) nTrans++;
1776: rc = sqlite3PagerExclusiveLock(sqlite3BtreePager(pBt));
1777: }
1778: }
1779: if( rc!=SQLITE_OK ){
1780: return rc;
1781: }
1782:
1783: /* If there are any write-transactions at all, invoke the commit hook */
1784: if( needXcommit && db->xCommitCallback ){
1785: rc = db->xCommitCallback(db->pCommitArg);
1786: if( rc ){
1787: return SQLITE_CONSTRAINT;
1788: }
1789: }
1790:
1791: /* The simple case - no more than one database file (not counting the
1792: ** TEMP database) has a transaction active. There is no need for the
1793: ** master-journal.
1794: **
1795: ** If the return value of sqlite3BtreeGetFilename() is a zero length
1796: ** string, it means the main database is :memory: or a temp file. In
1797: ** that case we do not support atomic multi-file commits, so use the
1798: ** simple case then too.
1799: */
1800: if( 0==sqlite3Strlen30(sqlite3BtreeGetFilename(db->aDb[0].pBt))
1801: || nTrans<=1
1802: ){
1803: for(i=0; rc==SQLITE_OK && i<db->nDb; i++){
1804: Btree *pBt = db->aDb[i].pBt;
1805: if( pBt ){
1806: rc = sqlite3BtreeCommitPhaseOne(pBt, 0);
1807: }
1808: }
1809:
1810: /* Do the commit only if all databases successfully complete phase 1.
1811: ** If one of the BtreeCommitPhaseOne() calls fails, this indicates an
1812: ** IO error while deleting or truncating a journal file. It is unlikely,
1813: ** but could happen. In this case abandon processing and return the error.
1814: */
1815: for(i=0; rc==SQLITE_OK && i<db->nDb; i++){
1816: Btree *pBt = db->aDb[i].pBt;
1817: if( pBt ){
1818: rc = sqlite3BtreeCommitPhaseTwo(pBt, 0);
1819: }
1820: }
1821: if( rc==SQLITE_OK ){
1822: sqlite3VtabCommit(db);
1823: }
1824: }
1825:
1826: /* The complex case - There is a multi-file write-transaction active.
1827: ** This requires a master journal file to ensure the transaction is
1828: ** committed atomicly.
1829: */
1830: #ifndef SQLITE_OMIT_DISKIO
1831: else{
1832: sqlite3_vfs *pVfs = db->pVfs;
1833: int needSync = 0;
1834: char *zMaster = 0; /* File-name for the master journal */
1835: char const *zMainFile = sqlite3BtreeGetFilename(db->aDb[0].pBt);
1836: sqlite3_file *pMaster = 0;
1837: i64 offset = 0;
1838: int res;
1839: int retryCount = 0;
1840: int nMainFile;
1841:
1842: /* Select a master journal file name */
1843: nMainFile = sqlite3Strlen30(zMainFile);
1844: zMaster = sqlite3MPrintf(db, "%s-mjXXXXXX9XXz", zMainFile);
1845: if( zMaster==0 ) return SQLITE_NOMEM;
1846: do {
1847: u32 iRandom;
1848: if( retryCount ){
1849: if( retryCount>100 ){
1850: sqlite3_log(SQLITE_FULL, "MJ delete: %s", zMaster);
1851: sqlite3OsDelete(pVfs, zMaster, 0);
1852: break;
1853: }else if( retryCount==1 ){
1854: sqlite3_log(SQLITE_FULL, "MJ collide: %s", zMaster);
1855: }
1856: }
1857: retryCount++;
1858: sqlite3_randomness(sizeof(iRandom), &iRandom);
1859: sqlite3_snprintf(13, &zMaster[nMainFile], "-mj%06X9%02X",
1860: (iRandom>>8)&0xffffff, iRandom&0xff);
1861: /* The antipenultimate character of the master journal name must
1862: ** be "9" to avoid name collisions when using 8+3 filenames. */
1863: assert( zMaster[sqlite3Strlen30(zMaster)-3]=='9' );
1864: sqlite3FileSuffix3(zMainFile, zMaster);
1865: rc = sqlite3OsAccess(pVfs, zMaster, SQLITE_ACCESS_EXISTS, &res);
1866: }while( rc==SQLITE_OK && res );
1867: if( rc==SQLITE_OK ){
1868: /* Open the master journal. */
1869: rc = sqlite3OsOpenMalloc(pVfs, zMaster, &pMaster,
1870: SQLITE_OPEN_READWRITE|SQLITE_OPEN_CREATE|
1871: SQLITE_OPEN_EXCLUSIVE|SQLITE_OPEN_MASTER_JOURNAL, 0
1872: );
1873: }
1874: if( rc!=SQLITE_OK ){
1875: sqlite3DbFree(db, zMaster);
1876: return rc;
1877: }
1878:
1879: /* Write the name of each database file in the transaction into the new
1880: ** master journal file. If an error occurs at this point close
1881: ** and delete the master journal file. All the individual journal files
1882: ** still have 'null' as the master journal pointer, so they will roll
1883: ** back independently if a failure occurs.
1884: */
1885: for(i=0; i<db->nDb; i++){
1886: Btree *pBt = db->aDb[i].pBt;
1887: if( sqlite3BtreeIsInTrans(pBt) ){
1888: char const *zFile = sqlite3BtreeGetJournalname(pBt);
1889: if( zFile==0 ){
1890: continue; /* Ignore TEMP and :memory: databases */
1891: }
1892: assert( zFile[0]!=0 );
1893: if( !needSync && !sqlite3BtreeSyncDisabled(pBt) ){
1894: needSync = 1;
1895: }
1896: rc = sqlite3OsWrite(pMaster, zFile, sqlite3Strlen30(zFile)+1, offset);
1897: offset += sqlite3Strlen30(zFile)+1;
1898: if( rc!=SQLITE_OK ){
1899: sqlite3OsCloseFree(pMaster);
1900: sqlite3OsDelete(pVfs, zMaster, 0);
1901: sqlite3DbFree(db, zMaster);
1902: return rc;
1903: }
1904: }
1905: }
1906:
1907: /* Sync the master journal file. If the IOCAP_SEQUENTIAL device
1908: ** flag is set this is not required.
1909: */
1910: if( needSync
1911: && 0==(sqlite3OsDeviceCharacteristics(pMaster)&SQLITE_IOCAP_SEQUENTIAL)
1912: && SQLITE_OK!=(rc = sqlite3OsSync(pMaster, SQLITE_SYNC_NORMAL))
1913: ){
1914: sqlite3OsCloseFree(pMaster);
1915: sqlite3OsDelete(pVfs, zMaster, 0);
1916: sqlite3DbFree(db, zMaster);
1917: return rc;
1918: }
1919:
1920: /* Sync all the db files involved in the transaction. The same call
1921: ** sets the master journal pointer in each individual journal. If
1922: ** an error occurs here, do not delete the master journal file.
1923: **
1924: ** If the error occurs during the first call to
1925: ** sqlite3BtreeCommitPhaseOne(), then there is a chance that the
1926: ** master journal file will be orphaned. But we cannot delete it,
1927: ** in case the master journal file name was written into the journal
1928: ** file before the failure occurred.
1929: */
1930: for(i=0; rc==SQLITE_OK && i<db->nDb; i++){
1931: Btree *pBt = db->aDb[i].pBt;
1932: if( pBt ){
1933: rc = sqlite3BtreeCommitPhaseOne(pBt, zMaster);
1934: }
1935: }
1936: sqlite3OsCloseFree(pMaster);
1937: assert( rc!=SQLITE_BUSY );
1938: if( rc!=SQLITE_OK ){
1939: sqlite3DbFree(db, zMaster);
1940: return rc;
1941: }
1942:
1943: /* Delete the master journal file. This commits the transaction. After
1944: ** doing this the directory is synced again before any individual
1945: ** transaction files are deleted.
1946: */
1947: rc = sqlite3OsDelete(pVfs, zMaster, 1);
1948: sqlite3DbFree(db, zMaster);
1949: zMaster = 0;
1950: if( rc ){
1951: return rc;
1952: }
1953:
1954: /* All files and directories have already been synced, so the following
1955: ** calls to sqlite3BtreeCommitPhaseTwo() are only closing files and
1956: ** deleting or truncating journals. If something goes wrong while
1957: ** this is happening we don't really care. The integrity of the
1958: ** transaction is already guaranteed, but some stray 'cold' journals
1959: ** may be lying around. Returning an error code won't help matters.
1960: */
1961: disable_simulated_io_errors();
1962: sqlite3BeginBenignMalloc();
1963: for(i=0; i<db->nDb; i++){
1964: Btree *pBt = db->aDb[i].pBt;
1965: if( pBt ){
1966: sqlite3BtreeCommitPhaseTwo(pBt, 1);
1967: }
1968: }
1969: sqlite3EndBenignMalloc();
1970: enable_simulated_io_errors();
1971:
1972: sqlite3VtabCommit(db);
1973: }
1974: #endif
1975:
1976: return rc;
1977: }
1978:
1979: /*
1980: ** This routine checks that the sqlite3.activeVdbeCnt count variable
1981: ** matches the number of vdbe's in the list sqlite3.pVdbe that are
1982: ** currently active. An assertion fails if the two counts do not match.
1983: ** This is an internal self-check only - it is not an essential processing
1984: ** step.
1985: **
1986: ** This is a no-op if NDEBUG is defined.
1987: */
1988: #ifndef NDEBUG
1989: static void checkActiveVdbeCnt(sqlite3 *db){
1990: Vdbe *p;
1991: int cnt = 0;
1992: int nWrite = 0;
1993: p = db->pVdbe;
1994: while( p ){
1995: if( p->magic==VDBE_MAGIC_RUN && p->pc>=0 ){
1996: cnt++;
1997: if( p->readOnly==0 ) nWrite++;
1998: }
1999: p = p->pNext;
2000: }
2001: assert( cnt==db->activeVdbeCnt );
2002: assert( nWrite==db->writeVdbeCnt );
2003: }
2004: #else
2005: #define checkActiveVdbeCnt(x)
2006: #endif
2007:
2008: /*
2009: ** For every Btree that in database connection db which
2010: ** has been modified, "trip" or invalidate each cursor in
2011: ** that Btree might have been modified so that the cursor
2012: ** can never be used again. This happens when a rollback
2013: *** occurs. We have to trip all the other cursors, even
2014: ** cursor from other VMs in different database connections,
2015: ** so that none of them try to use the data at which they
2016: ** were pointing and which now may have been changed due
2017: ** to the rollback.
2018: **
2019: ** Remember that a rollback can delete tables complete and
2020: ** reorder rootpages. So it is not sufficient just to save
2021: ** the state of the cursor. We have to invalidate the cursor
2022: ** so that it is never used again.
2023: */
2024: static void invalidateCursorsOnModifiedBtrees(sqlite3 *db){
2025: int i;
2026: for(i=0; i<db->nDb; i++){
2027: Btree *p = db->aDb[i].pBt;
2028: if( p && sqlite3BtreeIsInTrans(p) ){
2029: sqlite3BtreeTripAllCursors(p, SQLITE_ABORT);
2030: }
2031: }
2032: }
2033:
2034: /*
2035: ** If the Vdbe passed as the first argument opened a statement-transaction,
2036: ** close it now. Argument eOp must be either SAVEPOINT_ROLLBACK or
2037: ** SAVEPOINT_RELEASE. If it is SAVEPOINT_ROLLBACK, then the statement
2038: ** transaction is rolled back. If eOp is SAVEPOINT_RELEASE, then the
2039: ** statement transaction is commtted.
2040: **
2041: ** If an IO error occurs, an SQLITE_IOERR_XXX error code is returned.
2042: ** Otherwise SQLITE_OK.
2043: */
2044: int sqlite3VdbeCloseStatement(Vdbe *p, int eOp){
2045: sqlite3 *const db = p->db;
2046: int rc = SQLITE_OK;
2047:
2048: /* If p->iStatement is greater than zero, then this Vdbe opened a
2049: ** statement transaction that should be closed here. The only exception
2050: ** is that an IO error may have occured, causing an emergency rollback.
2051: ** In this case (db->nStatement==0), and there is nothing to do.
2052: */
2053: if( db->nStatement && p->iStatement ){
2054: int i;
2055: const int iSavepoint = p->iStatement-1;
2056:
2057: assert( eOp==SAVEPOINT_ROLLBACK || eOp==SAVEPOINT_RELEASE);
2058: assert( db->nStatement>0 );
2059: assert( p->iStatement==(db->nStatement+db->nSavepoint) );
2060:
2061: for(i=0; i<db->nDb; i++){
2062: int rc2 = SQLITE_OK;
2063: Btree *pBt = db->aDb[i].pBt;
2064: if( pBt ){
2065: if( eOp==SAVEPOINT_ROLLBACK ){
2066: rc2 = sqlite3BtreeSavepoint(pBt, SAVEPOINT_ROLLBACK, iSavepoint);
2067: }
2068: if( rc2==SQLITE_OK ){
2069: rc2 = sqlite3BtreeSavepoint(pBt, SAVEPOINT_RELEASE, iSavepoint);
2070: }
2071: if( rc==SQLITE_OK ){
2072: rc = rc2;
2073: }
2074: }
2075: }
2076: db->nStatement--;
2077: p->iStatement = 0;
2078:
2079: if( rc==SQLITE_OK ){
2080: if( eOp==SAVEPOINT_ROLLBACK ){
2081: rc = sqlite3VtabSavepoint(db, SAVEPOINT_ROLLBACK, iSavepoint);
2082: }
2083: if( rc==SQLITE_OK ){
2084: rc = sqlite3VtabSavepoint(db, SAVEPOINT_RELEASE, iSavepoint);
2085: }
2086: }
2087:
2088: /* If the statement transaction is being rolled back, also restore the
2089: ** database handles deferred constraint counter to the value it had when
2090: ** the statement transaction was opened. */
2091: if( eOp==SAVEPOINT_ROLLBACK ){
2092: db->nDeferredCons = p->nStmtDefCons;
2093: }
2094: }
2095: return rc;
2096: }
2097:
2098: /*
2099: ** This function is called when a transaction opened by the database
2100: ** handle associated with the VM passed as an argument is about to be
2101: ** committed. If there are outstanding deferred foreign key constraint
2102: ** violations, return SQLITE_ERROR. Otherwise, SQLITE_OK.
2103: **
2104: ** If there are outstanding FK violations and this function returns
2105: ** SQLITE_ERROR, set the result of the VM to SQLITE_CONSTRAINT and write
2106: ** an error message to it. Then return SQLITE_ERROR.
2107: */
2108: #ifndef SQLITE_OMIT_FOREIGN_KEY
2109: int sqlite3VdbeCheckFk(Vdbe *p, int deferred){
2110: sqlite3 *db = p->db;
2111: if( (deferred && db->nDeferredCons>0) || (!deferred && p->nFkConstraint>0) ){
2112: p->rc = SQLITE_CONSTRAINT;
2113: p->errorAction = OE_Abort;
2114: sqlite3SetString(&p->zErrMsg, db, "foreign key constraint failed");
2115: return SQLITE_ERROR;
2116: }
2117: return SQLITE_OK;
2118: }
2119: #endif
2120:
2121: /*
2122: ** This routine is called the when a VDBE tries to halt. If the VDBE
2123: ** has made changes and is in autocommit mode, then commit those
2124: ** changes. If a rollback is needed, then do the rollback.
2125: **
2126: ** This routine is the only way to move the state of a VM from
2127: ** SQLITE_MAGIC_RUN to SQLITE_MAGIC_HALT. It is harmless to
2128: ** call this on a VM that is in the SQLITE_MAGIC_HALT state.
2129: **
2130: ** Return an error code. If the commit could not complete because of
2131: ** lock contention, return SQLITE_BUSY. If SQLITE_BUSY is returned, it
2132: ** means the close did not happen and needs to be repeated.
2133: */
2134: int sqlite3VdbeHalt(Vdbe *p){
2135: int rc; /* Used to store transient return codes */
2136: sqlite3 *db = p->db;
2137:
2138: /* This function contains the logic that determines if a statement or
2139: ** transaction will be committed or rolled back as a result of the
2140: ** execution of this virtual machine.
2141: **
2142: ** If any of the following errors occur:
2143: **
2144: ** SQLITE_NOMEM
2145: ** SQLITE_IOERR
2146: ** SQLITE_FULL
2147: ** SQLITE_INTERRUPT
2148: **
2149: ** Then the internal cache might have been left in an inconsistent
2150: ** state. We need to rollback the statement transaction, if there is
2151: ** one, or the complete transaction if there is no statement transaction.
2152: */
2153:
2154: if( p->db->mallocFailed ){
2155: p->rc = SQLITE_NOMEM;
2156: }
2157: if( p->aOnceFlag ) memset(p->aOnceFlag, 0, p->nOnceFlag);
2158: closeAllCursors(p);
2159: if( p->magic!=VDBE_MAGIC_RUN ){
2160: return SQLITE_OK;
2161: }
2162: checkActiveVdbeCnt(db);
2163:
2164: /* No commit or rollback needed if the program never started */
2165: if( p->pc>=0 ){
2166: int mrc; /* Primary error code from p->rc */
2167: int eStatementOp = 0;
2168: int isSpecialError; /* Set to true if a 'special' error */
2169:
2170: /* Lock all btrees used by the statement */
2171: sqlite3VdbeEnter(p);
2172:
2173: /* Check for one of the special errors */
2174: mrc = p->rc & 0xff;
2175: assert( p->rc!=SQLITE_IOERR_BLOCKED ); /* This error no longer exists */
2176: isSpecialError = mrc==SQLITE_NOMEM || mrc==SQLITE_IOERR
2177: || mrc==SQLITE_INTERRUPT || mrc==SQLITE_FULL;
2178: if( isSpecialError ){
2179: /* If the query was read-only and the error code is SQLITE_INTERRUPT,
2180: ** no rollback is necessary. Otherwise, at least a savepoint
2181: ** transaction must be rolled back to restore the database to a
2182: ** consistent state.
2183: **
2184: ** Even if the statement is read-only, it is important to perform
2185: ** a statement or transaction rollback operation. If the error
2186: ** occured while writing to the journal, sub-journal or database
2187: ** file as part of an effort to free up cache space (see function
2188: ** pagerStress() in pager.c), the rollback is required to restore
2189: ** the pager to a consistent state.
2190: */
2191: if( !p->readOnly || mrc!=SQLITE_INTERRUPT ){
2192: if( (mrc==SQLITE_NOMEM || mrc==SQLITE_FULL) && p->usesStmtJournal ){
2193: eStatementOp = SAVEPOINT_ROLLBACK;
2194: }else{
2195: /* We are forced to roll back the active transaction. Before doing
2196: ** so, abort any other statements this handle currently has active.
2197: */
2198: invalidateCursorsOnModifiedBtrees(db);
2199: sqlite3RollbackAll(db);
2200: sqlite3CloseSavepoints(db);
2201: db->autoCommit = 1;
2202: }
2203: }
2204: }
2205:
2206: /* Check for immediate foreign key violations. */
2207: if( p->rc==SQLITE_OK ){
2208: sqlite3VdbeCheckFk(p, 0);
2209: }
2210:
2211: /* If the auto-commit flag is set and this is the only active writer
2212: ** VM, then we do either a commit or rollback of the current transaction.
2213: **
2214: ** Note: This block also runs if one of the special errors handled
2215: ** above has occurred.
2216: */
2217: if( !sqlite3VtabInSync(db)
2218: && db->autoCommit
2219: && db->writeVdbeCnt==(p->readOnly==0)
2220: ){
2221: if( p->rc==SQLITE_OK || (p->errorAction==OE_Fail && !isSpecialError) ){
2222: rc = sqlite3VdbeCheckFk(p, 1);
2223: if( rc!=SQLITE_OK ){
2224: if( NEVER(p->readOnly) ){
2225: sqlite3VdbeLeave(p);
2226: return SQLITE_ERROR;
2227: }
2228: rc = SQLITE_CONSTRAINT;
2229: }else{
2230: /* The auto-commit flag is true, the vdbe program was successful
2231: ** or hit an 'OR FAIL' constraint and there are no deferred foreign
2232: ** key constraints to hold up the transaction. This means a commit
2233: ** is required. */
2234: rc = vdbeCommit(db, p);
2235: }
2236: if( rc==SQLITE_BUSY && p->readOnly ){
2237: sqlite3VdbeLeave(p);
2238: return SQLITE_BUSY;
2239: }else if( rc!=SQLITE_OK ){
2240: p->rc = rc;
2241: sqlite3RollbackAll(db);
2242: }else{
2243: db->nDeferredCons = 0;
2244: sqlite3CommitInternalChanges(db);
2245: }
2246: }else{
2247: sqlite3RollbackAll(db);
2248: }
2249: db->nStatement = 0;
2250: }else if( eStatementOp==0 ){
2251: if( p->rc==SQLITE_OK || p->errorAction==OE_Fail ){
2252: eStatementOp = SAVEPOINT_RELEASE;
2253: }else if( p->errorAction==OE_Abort ){
2254: eStatementOp = SAVEPOINT_ROLLBACK;
2255: }else{
2256: invalidateCursorsOnModifiedBtrees(db);
2257: sqlite3RollbackAll(db);
2258: sqlite3CloseSavepoints(db);
2259: db->autoCommit = 1;
2260: }
2261: }
2262:
2263: /* If eStatementOp is non-zero, then a statement transaction needs to
2264: ** be committed or rolled back. Call sqlite3VdbeCloseStatement() to
2265: ** do so. If this operation returns an error, and the current statement
2266: ** error code is SQLITE_OK or SQLITE_CONSTRAINT, then promote the
2267: ** current statement error code.
2268: */
2269: if( eStatementOp ){
2270: rc = sqlite3VdbeCloseStatement(p, eStatementOp);
2271: if( rc ){
2272: if( p->rc==SQLITE_OK || p->rc==SQLITE_CONSTRAINT ){
2273: p->rc = rc;
2274: sqlite3DbFree(db, p->zErrMsg);
2275: p->zErrMsg = 0;
2276: }
2277: invalidateCursorsOnModifiedBtrees(db);
2278: sqlite3RollbackAll(db);
2279: sqlite3CloseSavepoints(db);
2280: db->autoCommit = 1;
2281: }
2282: }
2283:
2284: /* If this was an INSERT, UPDATE or DELETE and no statement transaction
2285: ** has been rolled back, update the database connection change-counter.
2286: */
2287: if( p->changeCntOn ){
2288: if( eStatementOp!=SAVEPOINT_ROLLBACK ){
2289: sqlite3VdbeSetChanges(db, p->nChange);
2290: }else{
2291: sqlite3VdbeSetChanges(db, 0);
2292: }
2293: p->nChange = 0;
2294: }
2295:
2296: /* Rollback or commit any schema changes that occurred. */
2297: if( p->rc!=SQLITE_OK && db->flags&SQLITE_InternChanges ){
2298: sqlite3ResetInternalSchema(db, -1);
2299: db->flags = (db->flags | SQLITE_InternChanges);
2300: }
2301:
2302: /* Release the locks */
2303: sqlite3VdbeLeave(p);
2304: }
2305:
2306: /* We have successfully halted and closed the VM. Record this fact. */
2307: if( p->pc>=0 ){
2308: db->activeVdbeCnt--;
2309: if( !p->readOnly ){
2310: db->writeVdbeCnt--;
2311: }
2312: assert( db->activeVdbeCnt>=db->writeVdbeCnt );
2313: }
2314: p->magic = VDBE_MAGIC_HALT;
2315: checkActiveVdbeCnt(db);
2316: if( p->db->mallocFailed ){
2317: p->rc = SQLITE_NOMEM;
2318: }
2319:
2320: /* If the auto-commit flag is set to true, then any locks that were held
2321: ** by connection db have now been released. Call sqlite3ConnectionUnlocked()
2322: ** to invoke any required unlock-notify callbacks.
2323: */
2324: if( db->autoCommit ){
2325: sqlite3ConnectionUnlocked(db);
2326: }
2327:
2328: assert( db->activeVdbeCnt>0 || db->autoCommit==0 || db->nStatement==0 );
2329: return (p->rc==SQLITE_BUSY ? SQLITE_BUSY : SQLITE_OK);
2330: }
2331:
2332:
2333: /*
2334: ** Each VDBE holds the result of the most recent sqlite3_step() call
2335: ** in p->rc. This routine sets that result back to SQLITE_OK.
2336: */
2337: void sqlite3VdbeResetStepResult(Vdbe *p){
2338: p->rc = SQLITE_OK;
2339: }
2340:
2341: /*
2342: ** Copy the error code and error message belonging to the VDBE passed
2343: ** as the first argument to its database handle (so that they will be
2344: ** returned by calls to sqlite3_errcode() and sqlite3_errmsg()).
2345: **
2346: ** This function does not clear the VDBE error code or message, just
2347: ** copies them to the database handle.
2348: */
2349: int sqlite3VdbeTransferError(Vdbe *p){
2350: sqlite3 *db = p->db;
2351: int rc = p->rc;
2352: if( p->zErrMsg ){
2353: u8 mallocFailed = db->mallocFailed;
2354: sqlite3BeginBenignMalloc();
2355: sqlite3ValueSetStr(db->pErr, -1, p->zErrMsg, SQLITE_UTF8, SQLITE_TRANSIENT);
2356: sqlite3EndBenignMalloc();
2357: db->mallocFailed = mallocFailed;
2358: db->errCode = rc;
2359: }else{
2360: sqlite3Error(db, rc, 0);
2361: }
2362: return rc;
2363: }
2364:
2365: /*
2366: ** Clean up a VDBE after execution but do not delete the VDBE just yet.
2367: ** Write any error messages into *pzErrMsg. Return the result code.
2368: **
2369: ** After this routine is run, the VDBE should be ready to be executed
2370: ** again.
2371: **
2372: ** To look at it another way, this routine resets the state of the
2373: ** virtual machine from VDBE_MAGIC_RUN or VDBE_MAGIC_HALT back to
2374: ** VDBE_MAGIC_INIT.
2375: */
2376: int sqlite3VdbeReset(Vdbe *p){
2377: sqlite3 *db;
2378: db = p->db;
2379:
2380: /* If the VM did not run to completion or if it encountered an
2381: ** error, then it might not have been halted properly. So halt
2382: ** it now.
2383: */
2384: sqlite3VdbeHalt(p);
2385:
2386: /* If the VDBE has be run even partially, then transfer the error code
2387: ** and error message from the VDBE into the main database structure. But
2388: ** if the VDBE has just been set to run but has not actually executed any
2389: ** instructions yet, leave the main database error information unchanged.
2390: */
2391: if( p->pc>=0 ){
2392: sqlite3VdbeTransferError(p);
2393: sqlite3DbFree(db, p->zErrMsg);
2394: p->zErrMsg = 0;
2395: if( p->runOnlyOnce ) p->expired = 1;
2396: }else if( p->rc && p->expired ){
2397: /* The expired flag was set on the VDBE before the first call
2398: ** to sqlite3_step(). For consistency (since sqlite3_step() was
2399: ** called), set the database error in this case as well.
2400: */
2401: sqlite3Error(db, p->rc, 0);
2402: sqlite3ValueSetStr(db->pErr, -1, p->zErrMsg, SQLITE_UTF8, SQLITE_TRANSIENT);
2403: sqlite3DbFree(db, p->zErrMsg);
2404: p->zErrMsg = 0;
2405: }
2406:
2407: /* Reclaim all memory used by the VDBE
2408: */
2409: Cleanup(p);
2410:
2411: /* Save profiling information from this VDBE run.
2412: */
2413: #ifdef VDBE_PROFILE
2414: {
2415: FILE *out = fopen("vdbe_profile.out", "a");
2416: if( out ){
2417: int i;
2418: fprintf(out, "---- ");
2419: for(i=0; i<p->nOp; i++){
2420: fprintf(out, "%02x", p->aOp[i].opcode);
2421: }
2422: fprintf(out, "\n");
2423: for(i=0; i<p->nOp; i++){
2424: fprintf(out, "%6d %10lld %8lld ",
2425: p->aOp[i].cnt,
2426: p->aOp[i].cycles,
2427: p->aOp[i].cnt>0 ? p->aOp[i].cycles/p->aOp[i].cnt : 0
2428: );
2429: sqlite3VdbePrintOp(out, i, &p->aOp[i]);
2430: }
2431: fclose(out);
2432: }
2433: }
2434: #endif
2435: p->magic = VDBE_MAGIC_INIT;
2436: return p->rc & db->errMask;
2437: }
2438:
2439: /*
2440: ** Clean up and delete a VDBE after execution. Return an integer which is
2441: ** the result code. Write any error message text into *pzErrMsg.
2442: */
2443: int sqlite3VdbeFinalize(Vdbe *p){
2444: int rc = SQLITE_OK;
2445: if( p->magic==VDBE_MAGIC_RUN || p->magic==VDBE_MAGIC_HALT ){
2446: rc = sqlite3VdbeReset(p);
2447: assert( (rc & p->db->errMask)==rc );
2448: }
2449: sqlite3VdbeDelete(p);
2450: return rc;
2451: }
2452:
2453: /*
2454: ** Call the destructor for each auxdata entry in pVdbeFunc for which
2455: ** the corresponding bit in mask is clear. Auxdata entries beyond 31
2456: ** are always destroyed. To destroy all auxdata entries, call this
2457: ** routine with mask==0.
2458: */
2459: void sqlite3VdbeDeleteAuxData(VdbeFunc *pVdbeFunc, int mask){
2460: int i;
2461: for(i=0; i<pVdbeFunc->nAux; i++){
2462: struct AuxData *pAux = &pVdbeFunc->apAux[i];
2463: if( (i>31 || !(mask&(((u32)1)<<i))) && pAux->pAux ){
2464: if( pAux->xDelete ){
2465: pAux->xDelete(pAux->pAux);
2466: }
2467: pAux->pAux = 0;
2468: }
2469: }
2470: }
2471:
2472: /*
2473: ** Free all memory associated with the Vdbe passed as the second argument.
2474: ** The difference between this function and sqlite3VdbeDelete() is that
2475: ** VdbeDelete() also unlinks the Vdbe from the list of VMs associated with
2476: ** the database connection.
2477: */
2478: void sqlite3VdbeDeleteObject(sqlite3 *db, Vdbe *p){
2479: SubProgram *pSub, *pNext;
2480: int i;
2481: assert( p->db==0 || p->db==db );
2482: releaseMemArray(p->aVar, p->nVar);
2483: releaseMemArray(p->aColName, p->nResColumn*COLNAME_N);
2484: for(pSub=p->pProgram; pSub; pSub=pNext){
2485: pNext = pSub->pNext;
2486: vdbeFreeOpArray(db, pSub->aOp, pSub->nOp);
2487: sqlite3DbFree(db, pSub);
2488: }
2489: for(i=p->nzVar-1; i>=0; i--) sqlite3DbFree(db, p->azVar[i]);
2490: vdbeFreeOpArray(db, p->aOp, p->nOp);
2491: sqlite3DbFree(db, p->aLabel);
2492: sqlite3DbFree(db, p->aColName);
2493: sqlite3DbFree(db, p->zSql);
2494: sqlite3DbFree(db, p->pFree);
2495: #if defined(SQLITE_ENABLE_TREE_EXPLAIN)
2496: sqlite3DbFree(db, p->zExplain);
2497: sqlite3DbFree(db, p->pExplain);
2498: #endif
2499: sqlite3DbFree(db, p);
2500: }
2501:
2502: /*
2503: ** Delete an entire VDBE.
2504: */
2505: void sqlite3VdbeDelete(Vdbe *p){
2506: sqlite3 *db;
2507:
2508: if( NEVER(p==0) ) return;
2509: db = p->db;
2510: if( p->pPrev ){
2511: p->pPrev->pNext = p->pNext;
2512: }else{
2513: assert( db->pVdbe==p );
2514: db->pVdbe = p->pNext;
2515: }
2516: if( p->pNext ){
2517: p->pNext->pPrev = p->pPrev;
2518: }
2519: p->magic = VDBE_MAGIC_DEAD;
2520: p->db = 0;
2521: sqlite3VdbeDeleteObject(db, p);
2522: }
2523:
2524: /*
2525: ** Make sure the cursor p is ready to read or write the row to which it
2526: ** was last positioned. Return an error code if an OOM fault or I/O error
2527: ** prevents us from positioning the cursor to its correct position.
2528: **
2529: ** If a MoveTo operation is pending on the given cursor, then do that
2530: ** MoveTo now. If no move is pending, check to see if the row has been
2531: ** deleted out from under the cursor and if it has, mark the row as
2532: ** a NULL row.
2533: **
2534: ** If the cursor is already pointing to the correct row and that row has
2535: ** not been deleted out from under the cursor, then this routine is a no-op.
2536: */
2537: int sqlite3VdbeCursorMoveto(VdbeCursor *p){
2538: if( p->deferredMoveto ){
2539: int res, rc;
2540: #ifdef SQLITE_TEST
2541: extern int sqlite3_search_count;
2542: #endif
2543: assert( p->isTable );
2544: rc = sqlite3BtreeMovetoUnpacked(p->pCursor, 0, p->movetoTarget, 0, &res);
2545: if( rc ) return rc;
2546: p->lastRowid = p->movetoTarget;
2547: if( res!=0 ) return SQLITE_CORRUPT_BKPT;
2548: p->rowidIsValid = 1;
2549: #ifdef SQLITE_TEST
2550: sqlite3_search_count++;
2551: #endif
2552: p->deferredMoveto = 0;
2553: p->cacheStatus = CACHE_STALE;
2554: }else if( ALWAYS(p->pCursor) ){
2555: int hasMoved;
2556: int rc = sqlite3BtreeCursorHasMoved(p->pCursor, &hasMoved);
2557: if( rc ) return rc;
2558: if( hasMoved ){
2559: p->cacheStatus = CACHE_STALE;
2560: p->nullRow = 1;
2561: }
2562: }
2563: return SQLITE_OK;
2564: }
2565:
2566: /*
2567: ** The following functions:
2568: **
2569: ** sqlite3VdbeSerialType()
2570: ** sqlite3VdbeSerialTypeLen()
2571: ** sqlite3VdbeSerialLen()
2572: ** sqlite3VdbeSerialPut()
2573: ** sqlite3VdbeSerialGet()
2574: **
2575: ** encapsulate the code that serializes values for storage in SQLite
2576: ** data and index records. Each serialized value consists of a
2577: ** 'serial-type' and a blob of data. The serial type is an 8-byte unsigned
2578: ** integer, stored as a varint.
2579: **
2580: ** In an SQLite index record, the serial type is stored directly before
2581: ** the blob of data that it corresponds to. In a table record, all serial
2582: ** types are stored at the start of the record, and the blobs of data at
2583: ** the end. Hence these functions allow the caller to handle the
2584: ** serial-type and data blob seperately.
2585: **
2586: ** The following table describes the various storage classes for data:
2587: **
2588: ** serial type bytes of data type
2589: ** -------------- --------------- ---------------
2590: ** 0 0 NULL
2591: ** 1 1 signed integer
2592: ** 2 2 signed integer
2593: ** 3 3 signed integer
2594: ** 4 4 signed integer
2595: ** 5 6 signed integer
2596: ** 6 8 signed integer
2597: ** 7 8 IEEE float
2598: ** 8 0 Integer constant 0
2599: ** 9 0 Integer constant 1
2600: ** 10,11 reserved for expansion
2601: ** N>=12 and even (N-12)/2 BLOB
2602: ** N>=13 and odd (N-13)/2 text
2603: **
2604: ** The 8 and 9 types were added in 3.3.0, file format 4. Prior versions
2605: ** of SQLite will not understand those serial types.
2606: */
2607:
2608: /*
2609: ** Return the serial-type for the value stored in pMem.
2610: */
2611: u32 sqlite3VdbeSerialType(Mem *pMem, int file_format){
2612: int flags = pMem->flags;
2613: int n;
2614:
2615: if( flags&MEM_Null ){
2616: return 0;
2617: }
2618: if( flags&MEM_Int ){
2619: /* Figure out whether to use 1, 2, 4, 6 or 8 bytes. */
2620: # define MAX_6BYTE ((((i64)0x00008000)<<32)-1)
2621: i64 i = pMem->u.i;
2622: u64 u;
2623: if( file_format>=4 && (i&1)==i ){
2624: return 8+(u32)i;
2625: }
2626: if( i<0 ){
2627: if( i<(-MAX_6BYTE) ) return 6;
2628: /* Previous test prevents: u = -(-9223372036854775808) */
2629: u = -i;
2630: }else{
2631: u = i;
2632: }
2633: if( u<=127 ) return 1;
2634: if( u<=32767 ) return 2;
2635: if( u<=8388607 ) return 3;
2636: if( u<=2147483647 ) return 4;
2637: if( u<=MAX_6BYTE ) return 5;
2638: return 6;
2639: }
2640: if( flags&MEM_Real ){
2641: return 7;
2642: }
2643: assert( pMem->db->mallocFailed || flags&(MEM_Str|MEM_Blob) );
2644: n = pMem->n;
2645: if( flags & MEM_Zero ){
2646: n += pMem->u.nZero;
2647: }
2648: assert( n>=0 );
2649: return ((n*2) + 12 + ((flags&MEM_Str)!=0));
2650: }
2651:
2652: /*
2653: ** Return the length of the data corresponding to the supplied serial-type.
2654: */
2655: u32 sqlite3VdbeSerialTypeLen(u32 serial_type){
2656: if( serial_type>=12 ){
2657: return (serial_type-12)/2;
2658: }else{
2659: static const u8 aSize[] = { 0, 1, 2, 3, 4, 6, 8, 8, 0, 0, 0, 0 };
2660: return aSize[serial_type];
2661: }
2662: }
2663:
2664: /*
2665: ** If we are on an architecture with mixed-endian floating
2666: ** points (ex: ARM7) then swap the lower 4 bytes with the
2667: ** upper 4 bytes. Return the result.
2668: **
2669: ** For most architectures, this is a no-op.
2670: **
2671: ** (later): It is reported to me that the mixed-endian problem
2672: ** on ARM7 is an issue with GCC, not with the ARM7 chip. It seems
2673: ** that early versions of GCC stored the two words of a 64-bit
2674: ** float in the wrong order. And that error has been propagated
2675: ** ever since. The blame is not necessarily with GCC, though.
2676: ** GCC might have just copying the problem from a prior compiler.
2677: ** I am also told that newer versions of GCC that follow a different
2678: ** ABI get the byte order right.
2679: **
2680: ** Developers using SQLite on an ARM7 should compile and run their
2681: ** application using -DSQLITE_DEBUG=1 at least once. With DEBUG
2682: ** enabled, some asserts below will ensure that the byte order of
2683: ** floating point values is correct.
2684: **
2685: ** (2007-08-30) Frank van Vugt has studied this problem closely
2686: ** and has send his findings to the SQLite developers. Frank
2687: ** writes that some Linux kernels offer floating point hardware
2688: ** emulation that uses only 32-bit mantissas instead of a full
2689: ** 48-bits as required by the IEEE standard. (This is the
2690: ** CONFIG_FPE_FASTFPE option.) On such systems, floating point
2691: ** byte swapping becomes very complicated. To avoid problems,
2692: ** the necessary byte swapping is carried out using a 64-bit integer
2693: ** rather than a 64-bit float. Frank assures us that the code here
2694: ** works for him. We, the developers, have no way to independently
2695: ** verify this, but Frank seems to know what he is talking about
2696: ** so we trust him.
2697: */
2698: #ifdef SQLITE_MIXED_ENDIAN_64BIT_FLOAT
2699: static u64 floatSwap(u64 in){
2700: union {
2701: u64 r;
2702: u32 i[2];
2703: } u;
2704: u32 t;
2705:
2706: u.r = in;
2707: t = u.i[0];
2708: u.i[0] = u.i[1];
2709: u.i[1] = t;
2710: return u.r;
2711: }
2712: # define swapMixedEndianFloat(X) X = floatSwap(X)
2713: #else
2714: # define swapMixedEndianFloat(X)
2715: #endif
2716:
2717: /*
2718: ** Write the serialized data blob for the value stored in pMem into
2719: ** buf. It is assumed that the caller has allocated sufficient space.
2720: ** Return the number of bytes written.
2721: **
2722: ** nBuf is the amount of space left in buf[]. nBuf must always be
2723: ** large enough to hold the entire field. Except, if the field is
2724: ** a blob with a zero-filled tail, then buf[] might be just the right
2725: ** size to hold everything except for the zero-filled tail. If buf[]
2726: ** is only big enough to hold the non-zero prefix, then only write that
2727: ** prefix into buf[]. But if buf[] is large enough to hold both the
2728: ** prefix and the tail then write the prefix and set the tail to all
2729: ** zeros.
2730: **
2731: ** Return the number of bytes actually written into buf[]. The number
2732: ** of bytes in the zero-filled tail is included in the return value only
2733: ** if those bytes were zeroed in buf[].
2734: */
2735: u32 sqlite3VdbeSerialPut(u8 *buf, int nBuf, Mem *pMem, int file_format){
2736: u32 serial_type = sqlite3VdbeSerialType(pMem, file_format);
2737: u32 len;
2738:
2739: /* Integer and Real */
2740: if( serial_type<=7 && serial_type>0 ){
2741: u64 v;
2742: u32 i;
2743: if( serial_type==7 ){
2744: assert( sizeof(v)==sizeof(pMem->r) );
2745: memcpy(&v, &pMem->r, sizeof(v));
2746: swapMixedEndianFloat(v);
2747: }else{
2748: v = pMem->u.i;
2749: }
2750: len = i = sqlite3VdbeSerialTypeLen(serial_type);
2751: assert( len<=(u32)nBuf );
2752: while( i-- ){
2753: buf[i] = (u8)(v&0xFF);
2754: v >>= 8;
2755: }
2756: return len;
2757: }
2758:
2759: /* String or blob */
2760: if( serial_type>=12 ){
2761: assert( pMem->n + ((pMem->flags & MEM_Zero)?pMem->u.nZero:0)
2762: == (int)sqlite3VdbeSerialTypeLen(serial_type) );
2763: assert( pMem->n<=nBuf );
2764: len = pMem->n;
2765: memcpy(buf, pMem->z, len);
2766: if( pMem->flags & MEM_Zero ){
2767: len += pMem->u.nZero;
2768: assert( nBuf>=0 );
2769: if( len > (u32)nBuf ){
2770: len = (u32)nBuf;
2771: }
2772: memset(&buf[pMem->n], 0, len-pMem->n);
2773: }
2774: return len;
2775: }
2776:
2777: /* NULL or constants 0 or 1 */
2778: return 0;
2779: }
2780:
2781: /*
2782: ** Deserialize the data blob pointed to by buf as serial type serial_type
2783: ** and store the result in pMem. Return the number of bytes read.
2784: */
2785: u32 sqlite3VdbeSerialGet(
2786: const unsigned char *buf, /* Buffer to deserialize from */
2787: u32 serial_type, /* Serial type to deserialize */
2788: Mem *pMem /* Memory cell to write value into */
2789: ){
2790: switch( serial_type ){
2791: case 10: /* Reserved for future use */
2792: case 11: /* Reserved for future use */
2793: case 0: { /* NULL */
2794: pMem->flags = MEM_Null;
2795: break;
2796: }
2797: case 1: { /* 1-byte signed integer */
2798: pMem->u.i = (signed char)buf[0];
2799: pMem->flags = MEM_Int;
2800: return 1;
2801: }
2802: case 2: { /* 2-byte signed integer */
2803: pMem->u.i = (((signed char)buf[0])<<8) | buf[1];
2804: pMem->flags = MEM_Int;
2805: return 2;
2806: }
2807: case 3: { /* 3-byte signed integer */
2808: pMem->u.i = (((signed char)buf[0])<<16) | (buf[1]<<8) | buf[2];
2809: pMem->flags = MEM_Int;
2810: return 3;
2811: }
2812: case 4: { /* 4-byte signed integer */
2813: pMem->u.i = (buf[0]<<24) | (buf[1]<<16) | (buf[2]<<8) | buf[3];
2814: pMem->flags = MEM_Int;
2815: return 4;
2816: }
2817: case 5: { /* 6-byte signed integer */
2818: u64 x = (((signed char)buf[0])<<8) | buf[1];
2819: u32 y = (buf[2]<<24) | (buf[3]<<16) | (buf[4]<<8) | buf[5];
2820: x = (x<<32) | y;
2821: pMem->u.i = *(i64*)&x;
2822: pMem->flags = MEM_Int;
2823: return 6;
2824: }
2825: case 6: /* 8-byte signed integer */
2826: case 7: { /* IEEE floating point */
2827: u64 x;
2828: u32 y;
2829: #if !defined(NDEBUG) && !defined(SQLITE_OMIT_FLOATING_POINT)
2830: /* Verify that integers and floating point values use the same
2831: ** byte order. Or, that if SQLITE_MIXED_ENDIAN_64BIT_FLOAT is
2832: ** defined that 64-bit floating point values really are mixed
2833: ** endian.
2834: */
2835: static const u64 t1 = ((u64)0x3ff00000)<<32;
2836: static const double r1 = 1.0;
2837: u64 t2 = t1;
2838: swapMixedEndianFloat(t2);
2839: assert( sizeof(r1)==sizeof(t2) && memcmp(&r1, &t2, sizeof(r1))==0 );
2840: #endif
2841:
2842: x = (buf[0]<<24) | (buf[1]<<16) | (buf[2]<<8) | buf[3];
2843: y = (buf[4]<<24) | (buf[5]<<16) | (buf[6]<<8) | buf[7];
2844: x = (x<<32) | y;
2845: if( serial_type==6 ){
2846: pMem->u.i = *(i64*)&x;
2847: pMem->flags = MEM_Int;
2848: }else{
2849: assert( sizeof(x)==8 && sizeof(pMem->r)==8 );
2850: swapMixedEndianFloat(x);
2851: memcpy(&pMem->r, &x, sizeof(x));
2852: pMem->flags = sqlite3IsNaN(pMem->r) ? MEM_Null : MEM_Real;
2853: }
2854: return 8;
2855: }
2856: case 8: /* Integer 0 */
2857: case 9: { /* Integer 1 */
2858: pMem->u.i = serial_type-8;
2859: pMem->flags = MEM_Int;
2860: return 0;
2861: }
2862: default: {
2863: u32 len = (serial_type-12)/2;
2864: pMem->z = (char *)buf;
2865: pMem->n = len;
2866: pMem->xDel = 0;
2867: if( serial_type&0x01 ){
2868: pMem->flags = MEM_Str | MEM_Ephem;
2869: }else{
2870: pMem->flags = MEM_Blob | MEM_Ephem;
2871: }
2872: return len;
2873: }
2874: }
2875: return 0;
2876: }
2877:
2878: /*
2879: ** This routine is used to allocate sufficient space for an UnpackedRecord
2880: ** structure large enough to be used with sqlite3VdbeRecordUnpack() if
2881: ** the first argument is a pointer to KeyInfo structure pKeyInfo.
2882: **
2883: ** The space is either allocated using sqlite3DbMallocRaw() or from within
2884: ** the unaligned buffer passed via the second and third arguments (presumably
2885: ** stack space). If the former, then *ppFree is set to a pointer that should
2886: ** be eventually freed by the caller using sqlite3DbFree(). Or, if the
2887: ** allocation comes from the pSpace/szSpace buffer, *ppFree is set to NULL
2888: ** before returning.
2889: **
2890: ** If an OOM error occurs, NULL is returned.
2891: */
2892: UnpackedRecord *sqlite3VdbeAllocUnpackedRecord(
2893: KeyInfo *pKeyInfo, /* Description of the record */
2894: char *pSpace, /* Unaligned space available */
2895: int szSpace, /* Size of pSpace[] in bytes */
2896: char **ppFree /* OUT: Caller should free this pointer */
2897: ){
2898: UnpackedRecord *p; /* Unpacked record to return */
2899: int nOff; /* Increment pSpace by nOff to align it */
2900: int nByte; /* Number of bytes required for *p */
2901:
2902: /* We want to shift the pointer pSpace up such that it is 8-byte aligned.
2903: ** Thus, we need to calculate a value, nOff, between 0 and 7, to shift
2904: ** it by. If pSpace is already 8-byte aligned, nOff should be zero.
2905: */
2906: nOff = (8 - (SQLITE_PTR_TO_INT(pSpace) & 7)) & 7;
2907: nByte = ROUND8(sizeof(UnpackedRecord)) + sizeof(Mem)*(pKeyInfo->nField+1);
2908: if( nByte>szSpace+nOff ){
2909: p = (UnpackedRecord *)sqlite3DbMallocRaw(pKeyInfo->db, nByte);
2910: *ppFree = (char *)p;
2911: if( !p ) return 0;
2912: }else{
2913: p = (UnpackedRecord*)&pSpace[nOff];
2914: *ppFree = 0;
2915: }
2916:
2917: p->aMem = (Mem*)&((char*)p)[ROUND8(sizeof(UnpackedRecord))];
2918: p->pKeyInfo = pKeyInfo;
2919: p->nField = pKeyInfo->nField + 1;
2920: return p;
2921: }
2922:
2923: /*
2924: ** Given the nKey-byte encoding of a record in pKey[], populate the
2925: ** UnpackedRecord structure indicated by the fourth argument with the
2926: ** contents of the decoded record.
2927: */
2928: void sqlite3VdbeRecordUnpack(
2929: KeyInfo *pKeyInfo, /* Information about the record format */
2930: int nKey, /* Size of the binary record */
2931: const void *pKey, /* The binary record */
2932: UnpackedRecord *p /* Populate this structure before returning. */
2933: ){
2934: const unsigned char *aKey = (const unsigned char *)pKey;
2935: int d;
2936: u32 idx; /* Offset in aKey[] to read from */
2937: u16 u; /* Unsigned loop counter */
2938: u32 szHdr;
2939: Mem *pMem = p->aMem;
2940:
2941: p->flags = 0;
2942: assert( EIGHT_BYTE_ALIGNMENT(pMem) );
2943: idx = getVarint32(aKey, szHdr);
2944: d = szHdr;
2945: u = 0;
2946: while( idx<szHdr && u<p->nField && d<=nKey ){
2947: u32 serial_type;
2948:
2949: idx += getVarint32(&aKey[idx], serial_type);
2950: pMem->enc = pKeyInfo->enc;
2951: pMem->db = pKeyInfo->db;
2952: /* pMem->flags = 0; // sqlite3VdbeSerialGet() will set this for us */
2953: pMem->zMalloc = 0;
2954: d += sqlite3VdbeSerialGet(&aKey[d], serial_type, pMem);
2955: pMem++;
2956: u++;
2957: }
2958: assert( u<=pKeyInfo->nField + 1 );
2959: p->nField = u;
2960: }
2961:
2962: /*
2963: ** This function compares the two table rows or index records
2964: ** specified by {nKey1, pKey1} and pPKey2. It returns a negative, zero
2965: ** or positive integer if key1 is less than, equal to or
2966: ** greater than key2. The {nKey1, pKey1} key must be a blob
2967: ** created by th OP_MakeRecord opcode of the VDBE. The pPKey2
2968: ** key must be a parsed key such as obtained from
2969: ** sqlite3VdbeParseRecord.
2970: **
2971: ** Key1 and Key2 do not have to contain the same number of fields.
2972: ** The key with fewer fields is usually compares less than the
2973: ** longer key. However if the UNPACKED_INCRKEY flags in pPKey2 is set
2974: ** and the common prefixes are equal, then key1 is less than key2.
2975: ** Or if the UNPACKED_MATCH_PREFIX flag is set and the prefixes are
2976: ** equal, then the keys are considered to be equal and
2977: ** the parts beyond the common prefix are ignored.
2978: */
2979: int sqlite3VdbeRecordCompare(
2980: int nKey1, const void *pKey1, /* Left key */
2981: UnpackedRecord *pPKey2 /* Right key */
2982: ){
2983: int d1; /* Offset into aKey[] of next data element */
2984: u32 idx1; /* Offset into aKey[] of next header element */
2985: u32 szHdr1; /* Number of bytes in header */
2986: int i = 0;
2987: int nField;
2988: int rc = 0;
2989: const unsigned char *aKey1 = (const unsigned char *)pKey1;
2990: KeyInfo *pKeyInfo;
2991: Mem mem1;
2992:
2993: pKeyInfo = pPKey2->pKeyInfo;
2994: mem1.enc = pKeyInfo->enc;
2995: mem1.db = pKeyInfo->db;
2996: /* mem1.flags = 0; // Will be initialized by sqlite3VdbeSerialGet() */
2997: VVA_ONLY( mem1.zMalloc = 0; ) /* Only needed by assert() statements */
2998:
2999: /* Compilers may complain that mem1.u.i is potentially uninitialized.
3000: ** We could initialize it, as shown here, to silence those complaints.
3001: ** But in fact, mem1.u.i will never actually be used uninitialized, and doing
3002: ** the unnecessary initialization has a measurable negative performance
3003: ** impact, since this routine is a very high runner. And so, we choose
3004: ** to ignore the compiler warnings and leave this variable uninitialized.
3005: */
3006: /* mem1.u.i = 0; // not needed, here to silence compiler warning */
3007:
3008: idx1 = getVarint32(aKey1, szHdr1);
3009: d1 = szHdr1;
3010: nField = pKeyInfo->nField;
3011: while( idx1<szHdr1 && i<pPKey2->nField ){
3012: u32 serial_type1;
3013:
3014: /* Read the serial types for the next element in each key. */
3015: idx1 += getVarint32( aKey1+idx1, serial_type1 );
3016: if( d1>=nKey1 && sqlite3VdbeSerialTypeLen(serial_type1)>0 ) break;
3017:
3018: /* Extract the values to be compared.
3019: */
3020: d1 += sqlite3VdbeSerialGet(&aKey1[d1], serial_type1, &mem1);
3021:
3022: /* Do the comparison
3023: */
3024: rc = sqlite3MemCompare(&mem1, &pPKey2->aMem[i],
3025: i<nField ? pKeyInfo->aColl[i] : 0);
3026: if( rc!=0 ){
3027: assert( mem1.zMalloc==0 ); /* See comment below */
3028:
3029: /* Invert the result if we are using DESC sort order. */
3030: if( pKeyInfo->aSortOrder && i<nField && pKeyInfo->aSortOrder[i] ){
3031: rc = -rc;
3032: }
3033:
3034: /* If the PREFIX_SEARCH flag is set and all fields except the final
3035: ** rowid field were equal, then clear the PREFIX_SEARCH flag and set
3036: ** pPKey2->rowid to the value of the rowid field in (pKey1, nKey1).
3037: ** This is used by the OP_IsUnique opcode.
3038: */
3039: if( (pPKey2->flags & UNPACKED_PREFIX_SEARCH) && i==(pPKey2->nField-1) ){
3040: assert( idx1==szHdr1 && rc );
3041: assert( mem1.flags & MEM_Int );
3042: pPKey2->flags &= ~UNPACKED_PREFIX_SEARCH;
3043: pPKey2->rowid = mem1.u.i;
3044: }
3045:
3046: return rc;
3047: }
3048: i++;
3049: }
3050:
3051: /* No memory allocation is ever used on mem1. Prove this using
3052: ** the following assert(). If the assert() fails, it indicates a
3053: ** memory leak and a need to call sqlite3VdbeMemRelease(&mem1).
3054: */
3055: assert( mem1.zMalloc==0 );
3056:
3057: /* rc==0 here means that one of the keys ran out of fields and
3058: ** all the fields up to that point were equal. If the UNPACKED_INCRKEY
3059: ** flag is set, then break the tie by treating key2 as larger.
3060: ** If the UPACKED_PREFIX_MATCH flag is set, then keys with common prefixes
3061: ** are considered to be equal. Otherwise, the longer key is the
3062: ** larger. As it happens, the pPKey2 will always be the longer
3063: ** if there is a difference.
3064: */
3065: assert( rc==0 );
3066: if( pPKey2->flags & UNPACKED_INCRKEY ){
3067: rc = -1;
3068: }else if( pPKey2->flags & UNPACKED_PREFIX_MATCH ){
3069: /* Leave rc==0 */
3070: }else if( idx1<szHdr1 ){
3071: rc = 1;
3072: }
3073: return rc;
3074: }
3075:
3076:
3077: /*
3078: ** pCur points at an index entry created using the OP_MakeRecord opcode.
3079: ** Read the rowid (the last field in the record) and store it in *rowid.
3080: ** Return SQLITE_OK if everything works, or an error code otherwise.
3081: **
3082: ** pCur might be pointing to text obtained from a corrupt database file.
3083: ** So the content cannot be trusted. Do appropriate checks on the content.
3084: */
3085: int sqlite3VdbeIdxRowid(sqlite3 *db, BtCursor *pCur, i64 *rowid){
3086: i64 nCellKey = 0;
3087: int rc;
3088: u32 szHdr; /* Size of the header */
3089: u32 typeRowid; /* Serial type of the rowid */
3090: u32 lenRowid; /* Size of the rowid */
3091: Mem m, v;
3092:
3093: UNUSED_PARAMETER(db);
3094:
3095: /* Get the size of the index entry. Only indices entries of less
3096: ** than 2GiB are support - anything large must be database corruption.
3097: ** Any corruption is detected in sqlite3BtreeParseCellPtr(), though, so
3098: ** this code can safely assume that nCellKey is 32-bits
3099: */
3100: assert( sqlite3BtreeCursorIsValid(pCur) );
3101: VVA_ONLY(rc =) sqlite3BtreeKeySize(pCur, &nCellKey);
3102: assert( rc==SQLITE_OK ); /* pCur is always valid so KeySize cannot fail */
3103: assert( (nCellKey & SQLITE_MAX_U32)==(u64)nCellKey );
3104:
3105: /* Read in the complete content of the index entry */
3106: memset(&m, 0, sizeof(m));
3107: rc = sqlite3VdbeMemFromBtree(pCur, 0, (int)nCellKey, 1, &m);
3108: if( rc ){
3109: return rc;
3110: }
3111:
3112: /* The index entry must begin with a header size */
3113: (void)getVarint32((u8*)m.z, szHdr);
3114: testcase( szHdr==3 );
3115: testcase( szHdr==m.n );
3116: if( unlikely(szHdr<3 || (int)szHdr>m.n) ){
3117: goto idx_rowid_corruption;
3118: }
3119:
3120: /* The last field of the index should be an integer - the ROWID.
3121: ** Verify that the last entry really is an integer. */
3122: (void)getVarint32((u8*)&m.z[szHdr-1], typeRowid);
3123: testcase( typeRowid==1 );
3124: testcase( typeRowid==2 );
3125: testcase( typeRowid==3 );
3126: testcase( typeRowid==4 );
3127: testcase( typeRowid==5 );
3128: testcase( typeRowid==6 );
3129: testcase( typeRowid==8 );
3130: testcase( typeRowid==9 );
3131: if( unlikely(typeRowid<1 || typeRowid>9 || typeRowid==7) ){
3132: goto idx_rowid_corruption;
3133: }
3134: lenRowid = sqlite3VdbeSerialTypeLen(typeRowid);
3135: testcase( (u32)m.n==szHdr+lenRowid );
3136: if( unlikely((u32)m.n<szHdr+lenRowid) ){
3137: goto idx_rowid_corruption;
3138: }
3139:
3140: /* Fetch the integer off the end of the index record */
3141: sqlite3VdbeSerialGet((u8*)&m.z[m.n-lenRowid], typeRowid, &v);
3142: *rowid = v.u.i;
3143: sqlite3VdbeMemRelease(&m);
3144: return SQLITE_OK;
3145:
3146: /* Jump here if database corruption is detected after m has been
3147: ** allocated. Free the m object and return SQLITE_CORRUPT. */
3148: idx_rowid_corruption:
3149: testcase( m.zMalloc!=0 );
3150: sqlite3VdbeMemRelease(&m);
3151: return SQLITE_CORRUPT_BKPT;
3152: }
3153:
3154: /*
3155: ** Compare the key of the index entry that cursor pC is pointing to against
3156: ** the key string in pUnpacked. Write into *pRes a number
3157: ** that is negative, zero, or positive if pC is less than, equal to,
3158: ** or greater than pUnpacked. Return SQLITE_OK on success.
3159: **
3160: ** pUnpacked is either created without a rowid or is truncated so that it
3161: ** omits the rowid at the end. The rowid at the end of the index entry
3162: ** is ignored as well. Hence, this routine only compares the prefixes
3163: ** of the keys prior to the final rowid, not the entire key.
3164: */
3165: int sqlite3VdbeIdxKeyCompare(
3166: VdbeCursor *pC, /* The cursor to compare against */
3167: UnpackedRecord *pUnpacked, /* Unpacked version of key to compare against */
3168: int *res /* Write the comparison result here */
3169: ){
3170: i64 nCellKey = 0;
3171: int rc;
3172: BtCursor *pCur = pC->pCursor;
3173: Mem m;
3174:
3175: assert( sqlite3BtreeCursorIsValid(pCur) );
3176: VVA_ONLY(rc =) sqlite3BtreeKeySize(pCur, &nCellKey);
3177: assert( rc==SQLITE_OK ); /* pCur is always valid so KeySize cannot fail */
3178: /* nCellKey will always be between 0 and 0xffffffff because of the say
3179: ** that btreeParseCellPtr() and sqlite3GetVarint32() are implemented */
3180: if( nCellKey<=0 || nCellKey>0x7fffffff ){
3181: *res = 0;
3182: return SQLITE_CORRUPT_BKPT;
3183: }
3184: memset(&m, 0, sizeof(m));
3185: rc = sqlite3VdbeMemFromBtree(pC->pCursor, 0, (int)nCellKey, 1, &m);
3186: if( rc ){
3187: return rc;
3188: }
3189: assert( pUnpacked->flags & UNPACKED_PREFIX_MATCH );
3190: *res = sqlite3VdbeRecordCompare(m.n, m.z, pUnpacked);
3191: sqlite3VdbeMemRelease(&m);
3192: return SQLITE_OK;
3193: }
3194:
3195: /*
3196: ** This routine sets the value to be returned by subsequent calls to
3197: ** sqlite3_changes() on the database handle 'db'.
3198: */
3199: void sqlite3VdbeSetChanges(sqlite3 *db, int nChange){
3200: assert( sqlite3_mutex_held(db->mutex) );
3201: db->nChange = nChange;
3202: db->nTotalChange += nChange;
3203: }
3204:
3205: /*
3206: ** Set a flag in the vdbe to update the change counter when it is finalised
3207: ** or reset.
3208: */
3209: void sqlite3VdbeCountChanges(Vdbe *v){
3210: v->changeCntOn = 1;
3211: }
3212:
3213: /*
3214: ** Mark every prepared statement associated with a database connection
3215: ** as expired.
3216: **
3217: ** An expired statement means that recompilation of the statement is
3218: ** recommend. Statements expire when things happen that make their
3219: ** programs obsolete. Removing user-defined functions or collating
3220: ** sequences, or changing an authorization function are the types of
3221: ** things that make prepared statements obsolete.
3222: */
3223: void sqlite3ExpirePreparedStatements(sqlite3 *db){
3224: Vdbe *p;
3225: for(p = db->pVdbe; p; p=p->pNext){
3226: p->expired = 1;
3227: }
3228: }
3229:
3230: /*
3231: ** Return the database associated with the Vdbe.
3232: */
3233: sqlite3 *sqlite3VdbeDb(Vdbe *v){
3234: return v->db;
3235: }
3236:
3237: /*
3238: ** Return a pointer to an sqlite3_value structure containing the value bound
3239: ** parameter iVar of VM v. Except, if the value is an SQL NULL, return
3240: ** 0 instead. Unless it is NULL, apply affinity aff (one of the SQLITE_AFF_*
3241: ** constants) to the value before returning it.
3242: **
3243: ** The returned value must be freed by the caller using sqlite3ValueFree().
3244: */
3245: sqlite3_value *sqlite3VdbeGetValue(Vdbe *v, int iVar, u8 aff){
3246: assert( iVar>0 );
3247: if( v ){
3248: Mem *pMem = &v->aVar[iVar-1];
3249: if( 0==(pMem->flags & MEM_Null) ){
3250: sqlite3_value *pRet = sqlite3ValueNew(v->db);
3251: if( pRet ){
3252: sqlite3VdbeMemCopy((Mem *)pRet, pMem);
3253: sqlite3ValueApplyAffinity(pRet, aff, SQLITE_UTF8);
3254: sqlite3VdbeMemStoreType((Mem *)pRet);
3255: }
3256: return pRet;
3257: }
3258: }
3259: return 0;
3260: }
3261:
3262: /*
3263: ** Configure SQL variable iVar so that binding a new value to it signals
3264: ** to sqlite3_reoptimize() that re-preparing the statement may result
3265: ** in a better query plan.
3266: */
3267: void sqlite3VdbeSetVarmask(Vdbe *v, int iVar){
3268: assert( iVar>0 );
3269: if( iVar>32 ){
3270: v->expmask = 0xffffffff;
3271: }else{
3272: v->expmask |= ((u32)1 << (iVar-1));
3273: }
3274: }
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