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cobalt / cobalt / d2bc3b69d823bbaf46d1c4355b23486a85a6d791 / . / third_party / sqlite / src / src / vdbeaux.c
blob: 4d4bb224f93d8ce16b7b653344164df9a026f624 [file] [log] [blame]
/*
** 2003 September 6
**
** The author disclaims copyright to this source code. In place of
** a legal notice, here is a blessing:
**
** May you do good and not evil.
** May you find forgiveness for yourself and forgive others.
** May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains code used for creating, destroying, and populating
** a VDBE (or an "sqlite3_stmt" as it is known to the outside world.) Prior
** to version 2.8.7, all this code was combined into the vdbe.c source file.
** But that file was getting too big so this subroutines were split out.
*/
#include "sqliteInt.h"
#include "vdbeInt.h"
/*
** When debugging the code generator in a symbolic debugger, one can
** set the sqlite3VdbeAddopTrace to 1 and all opcodes will be printed
** as they are added to the instruction stream.
*/
#ifdef SQLITE_DEBUG
int sqlite3VdbeAddopTrace = 0;
#endif
/*
** Create a new virtual database engine.
*/
Vdbe *sqlite3VdbeCreate(sqlite3 *db){
Vdbe *p;
p = sqlite3DbMallocZero(db, sizeof(Vdbe) );
if( p==0 ) return 0;
p->db = db;
if( db->pVdbe ){
db->pVdbe->pPrev = p;
}
p->pNext = db->pVdbe;
p->pPrev = 0;
db->pVdbe = p;
p->magic = VDBE_MAGIC_INIT;
return p;
}
/*
** Remember the SQL string for a prepared statement.
*/
void sqlite3VdbeSetSql(Vdbe *p, const char *z, int n, int isPrepareV2){
assert( isPrepareV2==1 || isPrepareV2==0 );
if( p==0 ) return;
#ifdef SQLITE_OMIT_TRACE
if( !isPrepareV2 ) return;
#endif
assert( p->zSql==0 );
p->zSql = sqlite3DbStrNDup(p->db, z, n);
p->isPrepareV2 = (u8)isPrepareV2;
}
/*
** Return the SQL associated with a prepared statement
*/
const char *sqlite3_sql(sqlite3_stmt *pStmt){
Vdbe *p = (Vdbe *)pStmt;
return (p && p->isPrepareV2) ? p->zSql : 0;
}
/*
** Swap all content between two VDBE structures.
*/
void sqlite3VdbeSwap(Vdbe *pA, Vdbe *pB){
Vdbe tmp, *pTmp;
char *zTmp;
tmp = *pA;
*pA = *pB;
*pB = tmp;
pTmp = pA->pNext;
pA->pNext = pB->pNext;
pB->pNext = pTmp;
pTmp = pA->pPrev;
pA->pPrev = pB->pPrev;
pB->pPrev = pTmp;
zTmp = pA->zSql;
pA->zSql = pB->zSql;
pB->zSql = zTmp;
pB->isPrepareV2 = pA->isPrepareV2;
}
#ifdef SQLITE_DEBUG
/*
** Turn tracing on or off
*/
void sqlite3VdbeTrace(Vdbe *p, FILE *trace){
p->trace = trace;
}
#endif
/*
** Resize the Vdbe.aOp array so that it is at least one op larger than
** it was.
**
** If an out-of-memory error occurs while resizing the array, return
** SQLITE_NOMEM. In this case Vdbe.aOp and Vdbe.nOpAlloc remain
** unchanged (this is so that any opcodes already allocated can be
** correctly deallocated along with the rest of the Vdbe).
*/
static int growOpArray(Vdbe *p){
VdbeOp *pNew;
int nNew = (p->nOpAlloc ? p->nOpAlloc*2 : (int)(1024/sizeof(Op)));
pNew = sqlite3DbRealloc(p->db, p->aOp, nNew*sizeof(Op));
if( pNew ){
p->nOpAlloc = sqlite3DbMallocSize(p->db, pNew)/sizeof(Op);
p->aOp = pNew;
}
return (pNew ? SQLITE_OK : SQLITE_NOMEM);
}
/*
** Add a new instruction to the list of instructions current in the
** VDBE. Return the address of the new instruction.
**
** Parameters:
**
** p Pointer to the VDBE
**
** op The opcode for this instruction
**
** p1, p2, p3 Operands
**
** Use the sqlite3VdbeResolveLabel() function to fix an address and
** the sqlite3VdbeChangeP4() function to change the value of the P4
** operand.
*/
int sqlite3VdbeAddOp3(Vdbe *p, int op, int p1, int p2, int p3){
int i;
VdbeOp *pOp;
i = p->nOp;
assert( p->magic==VDBE_MAGIC_INIT );
assert( op>0 && op<0xff );
if( p->nOpAlloc<=i ){
if( growOpArray(p) ){
return 1;
}
}
p->nOp++;
pOp = &p->aOp[i];
pOp->opcode = (u8)op;
pOp->p5 = 0;
pOp->p1 = p1;
pOp->p2 = p2;
pOp->p3 = p3;
pOp->p4.p = 0;
pOp->p4type = P4_NOTUSED;
p->expired = 0;
if( op==OP_ParseSchema ){
/* Any program that uses the OP_ParseSchema opcode needs to lock
** all btrees. */
int j;
for(j=0; j<p->db->nDb; j++) sqlite3VdbeUsesBtree(p, j);
}
#ifdef SQLITE_DEBUG
pOp->zComment = 0;
if( sqlite3VdbeAddopTrace ) sqlite3VdbePrintOp(0, i, &p->aOp[i]);
#endif
#ifdef VDBE_PROFILE
pOp->cycles = 0;
pOp->cnt = 0;
#endif
return i;
}
int sqlite3VdbeAddOp0(Vdbe *p, int op){
return sqlite3VdbeAddOp3(p, op, 0, 0, 0);
}
int sqlite3VdbeAddOp1(Vdbe *p, int op, int p1){
return sqlite3VdbeAddOp3(p, op, p1, 0, 0);
}
int sqlite3VdbeAddOp2(Vdbe *p, int op, int p1, int p2){
return sqlite3VdbeAddOp3(p, op, p1, p2, 0);
}
/*
** Add an opcode that includes the p4 value as a pointer.
*/
int sqlite3VdbeAddOp4(
Vdbe *p, /* Add the opcode to this VM */
int op, /* The new opcode */
int p1, /* The P1 operand */
int p2, /* The P2 operand */
int p3, /* The P3 operand */
const char *zP4, /* The P4 operand */
int p4type /* P4 operand type */
){
int addr = sqlite3VdbeAddOp3(p, op, p1, p2, p3);
sqlite3VdbeChangeP4(p, addr, zP4, p4type);
return addr;
}
/*
** Add an opcode that includes the p4 value as an integer.
*/
int sqlite3VdbeAddOp4Int(
Vdbe *p, /* Add the opcode to this VM */
int op, /* The new opcode */
int p1, /* The P1 operand */
int p2, /* The P2 operand */
int p3, /* The P3 operand */
int p4 /* The P4 operand as an integer */
){
int addr = sqlite3VdbeAddOp3(p, op, p1, p2, p3);
sqlite3VdbeChangeP4(p, addr, SQLITE_INT_TO_PTR(p4), P4_INT32);
return addr;
}
/*
** Create a new symbolic label for an instruction that has yet to be
** coded. The symbolic label is really just a negative number. The
** label can be used as the P2 value of an operation. Later, when
** the label is resolved to a specific address, the VDBE will scan
** through its operation list and change all values of P2 which match
** the label into the resolved address.
**
** The VDBE knows that a P2 value is a label because labels are
** always negative and P2 values are suppose to be non-negative.
** Hence, a negative P2 value is a label that has yet to be resolved.
**
** Zero is returned if a malloc() fails.
*/
int sqlite3VdbeMakeLabel(Vdbe *p){
int i;
i = p->nLabel++;
assert( p->magic==VDBE_MAGIC_INIT );
if( i>=p->nLabelAlloc ){
int n = p->nLabelAlloc*2 + 5;
p->aLabel = sqlite3DbReallocOrFree(p->db, p->aLabel,
n*sizeof(p->aLabel[0]));
p->nLabelAlloc = sqlite3DbMallocSize(p->db, p->aLabel)/sizeof(p->aLabel[0]);
}
if( p->aLabel ){
p->aLabel[i] = -1;
}
return -1-i;
}
/*
** Resolve label "x" to be the address of the next instruction to
** be inserted. The parameter "x" must have been obtained from
** a prior call to sqlite3VdbeMakeLabel().
*/
void sqlite3VdbeResolveLabel(Vdbe *p, int x){
int j = -1-x;
assert( p->magic==VDBE_MAGIC_INIT );
assert( j>=0 && j<p->nLabel );
if( p->aLabel ){
p->aLabel[j] = p->nOp;
}
}
/*
** Mark the VDBE as one that can only be run one time.
*/
void sqlite3VdbeRunOnlyOnce(Vdbe *p){
p->runOnlyOnce = 1;
}
#ifdef SQLITE_DEBUG /* sqlite3AssertMayAbort() logic */
/*
** The following type and function are used to iterate through all opcodes
** in a Vdbe main program and each of the sub-programs (triggers) it may
** invoke directly or indirectly. It should be used as follows:
**
** Op *pOp;
** VdbeOpIter sIter;
**
** memset(&sIter, 0, sizeof(sIter));
** sIter.v = v; // v is of type Vdbe*
** while( (pOp = opIterNext(&sIter)) ){
** // Do something with pOp
** }
** sqlite3DbFree(v->db, sIter.apSub);
**
*/
typedef struct VdbeOpIter VdbeOpIter;
struct VdbeOpIter {
Vdbe *v; /* Vdbe to iterate through the opcodes of */
SubProgram **apSub; /* Array of subprograms */
int nSub; /* Number of entries in apSub */
int iAddr; /* Address of next instruction to return */
int iSub; /* 0 = main program, 1 = first sub-program etc. */
};
static Op *opIterNext(VdbeOpIter *p){
Vdbe *v = p->v;
Op *pRet = 0;
Op *aOp;
int nOp;
if( p->iSub<=p->nSub ){
if( p->iSub==0 ){
aOp = v->aOp;
nOp = v->nOp;
}else{
aOp = p->apSub[p->iSub-1]->aOp;
nOp = p->apSub[p->iSub-1]->nOp;
}
assert( p->iAddr<nOp );
pRet = &aOp[p->iAddr];
p->iAddr++;
if( p->iAddr==nOp ){
p->iSub++;
p->iAddr = 0;
}
if( pRet->p4type==P4_SUBPROGRAM ){
int nByte = (p->nSub+1)*sizeof(SubProgram*);
int j;
for(j=0; j<p->nSub; j++){
if( p->apSub[j]==pRet->p4.pProgram ) break;
}
if( j==p->nSub ){
p->apSub = sqlite3DbReallocOrFree(v->db, p->apSub, nByte);
if( !p->apSub ){
pRet = 0;
}else{
p->apSub[p->nSub++] = pRet->p4.pProgram;
}
}
}
}
return pRet;
}
/*
** Check if the program stored in the VM associated with pParse may
** throw an ABORT exception (causing the statement, but not entire transaction
** to be rolled back). This condition is true if the main program or any
** sub-programs contains any of the following:
**
** * OP_Halt with P1=SQLITE_CONSTRAINT and P2=OE_Abort.
** * OP_HaltIfNull with P1=SQLITE_CONSTRAINT and P2=OE_Abort.
** * OP_Destroy
** * OP_VUpdate
** * OP_VRename
** * OP_FkCounter with P2==0 (immediate foreign key constraint)
**
** Then check that the value of Parse.mayAbort is true if an
** ABORT may be thrown, or false otherwise. Return true if it does
** match, or false otherwise. This function is intended to be used as
** part of an assert statement in the compiler. Similar to:
**
** assert( sqlite3VdbeAssertMayAbort(pParse->pVdbe, pParse->mayAbort) );
*/
int sqlite3VdbeAssertMayAbort(Vdbe *v, int mayAbort){
int hasAbort = 0;
Op *pOp;
VdbeOpIter sIter;
memset(&sIter, 0, sizeof(sIter));
sIter.v = v;
while( (pOp = opIterNext(&sIter))!=0 ){
int opcode = pOp->opcode;
if( opcode==OP_Destroy || opcode==OP_VUpdate || opcode==OP_VRename
#ifndef SQLITE_OMIT_FOREIGN_KEY
|| (opcode==OP_FkCounter && pOp->p1==0 && pOp->p2==1)
#endif
|| ((opcode==OP_Halt || opcode==OP_HaltIfNull)
&& (pOp->p1==SQLITE_CONSTRAINT && pOp->p2==OE_Abort))
){
hasAbort = 1;
break;
}
}
sqlite3DbFree(v->db, sIter.apSub);
/* Return true if hasAbort==mayAbort. Or if a malloc failure occured.
** If malloc failed, then the while() loop above may not have iterated
** through all opcodes and hasAbort may be set incorrectly. Return
** true for this case to prevent the assert() in the callers frame
** from failing. */
return ( v->db->mallocFailed || hasAbort==mayAbort );
}
#endif /* SQLITE_DEBUG - the sqlite3AssertMayAbort() function */
/*
** Loop through the program looking for P2 values that are negative
** on jump instructions. Each such value is a label. Resolve the
** label by setting the P2 value to its correct non-zero value.
**
** This routine is called once after all opcodes have been inserted.
**
** Variable *pMaxFuncArgs is set to the maximum value of any P2 argument
** to an OP_Function, OP_AggStep or OP_VFilter opcode. This is used by
** sqlite3VdbeMakeReady() to size the Vdbe.apArg[] array.
**
** The Op.opflags field is set on all opcodes.
*/
static void resolveP2Values(Vdbe *p, int *pMaxFuncArgs){
int i;
int nMaxArgs = *pMaxFuncArgs;
Op *pOp;
int *aLabel = p->aLabel;
p->readOnly = 1;
for(pOp=p->aOp, i=p->nOp-1; i>=0; i--, pOp++){
u8 opcode = pOp->opcode;
pOp->opflags = sqlite3OpcodeProperty[opcode];
if( opcode==OP_Function || opcode==OP_AggStep ){
if( pOp->p5>nMaxArgs ) nMaxArgs = pOp->p5;
}else if( (opcode==OP_Transaction && pOp->p2!=0) || opcode==OP_Vacuum ){
p->readOnly = 0;
#ifndef SQLITE_OMIT_VIRTUALTABLE
}else if( opcode==OP_VUpdate ){
if( pOp->p2>nMaxArgs ) nMaxArgs = pOp->p2;
}else if( opcode==OP_VFilter ){
int n;
assert( p->nOp - i >= 3 );
assert( pOp[-1].opcode==OP_Integer );
n = pOp[-1].p1;
if( n>nMaxArgs ) nMaxArgs = n;
#endif
}
if( (pOp->opflags & OPFLG_JUMP)!=0 && pOp->p2<0 ){
assert( -1-pOp->p2<p->nLabel );
pOp->p2 = aLabel[-1-pOp->p2];
}
}
sqlite3DbFree(p->db, p->aLabel);
p->aLabel = 0;
*pMaxFuncArgs = nMaxArgs;
}
/*
** Return the address of the next instruction to be inserted.
*/
int sqlite3VdbeCurrentAddr(Vdbe *p){
assert( p->magic==VDBE_MAGIC_INIT );
return p->nOp;
}
/*
** This function returns a pointer to the array of opcodes associated with
** the Vdbe passed as the first argument. It is the callers responsibility
** to arrange for the returned array to be eventually freed using the
** vdbeFreeOpArray() function.
**
** Before returning, *pnOp is set to the number of entries in the returned
** array. Also, *pnMaxArg is set to the larger of its current value and
** the number of entries in the Vdbe.apArg[] array required to execute the
** returned program.
*/
VdbeOp *sqlite3VdbeTakeOpArray(Vdbe *p, int *pnOp, int *pnMaxArg){
VdbeOp *aOp = p->aOp;
assert( aOp && !p->db->mallocFailed );
/* Check that sqlite3VdbeUsesBtree() was not called on this VM */
assert( p->btreeMask==0 );
resolveP2Values(p, pnMaxArg);
*pnOp = p->nOp;
p->aOp = 0;
return aOp;
}
/*
** Add a whole list of operations to the operation stack. Return the
** address of the first operation added.
*/
int sqlite3VdbeAddOpList(Vdbe *p, int nOp, VdbeOpList const *aOp){
int addr;
assert( p->magic==VDBE_MAGIC_INIT );
if( p->nOp + nOp > p->nOpAlloc && growOpArray(p) ){
return 0;
}
addr = p->nOp;
if( ALWAYS(nOp>0) ){
int i;
VdbeOpList const *pIn = aOp;
for(i=0; i<nOp; i++, pIn++){
int p2 = pIn->p2;
VdbeOp *pOut = &p->aOp[i+addr];
pOut->opcode = pIn->opcode;
pOut->p1 = pIn->p1;
if( p2<0 && (sqlite3OpcodeProperty[pOut->opcode] & OPFLG_JUMP)!=0 ){
pOut->p2 = addr + ADDR(p2);
}else{
pOut->p2 = p2;
}
pOut->p3 = pIn->p3;
pOut->p4type = P4_NOTUSED;
pOut->p4.p = 0;
pOut->p5 = 0;
#ifdef SQLITE_DEBUG
pOut->zComment = 0;
if( sqlite3VdbeAddopTrace ){
sqlite3VdbePrintOp(0, i+addr, &p->aOp[i+addr]);
}
#endif
}
p->nOp += nOp;
}
return addr;
}
/*
** Change the value of the P1 operand for a specific instruction.
** This routine is useful when a large program is loaded from a
** static array using sqlite3VdbeAddOpList but we want to make a
** few minor changes to the program.
*/
void sqlite3VdbeChangeP1(Vdbe *p, int addr, int val){
assert( p!=0 );
assert( addr>=0 );
if( p->nOp>addr ){
p->aOp[addr].p1 = val;
}
}
/*
** Change the value of the P2 operand for a specific instruction.
** This routine is useful for setting a jump destination.
*/
void sqlite3VdbeChangeP2(Vdbe *p, int addr, int val){
assert( p!=0 );
assert( addr>=0 );
if( p->nOp>addr ){
p->aOp[addr].p2 = val;
}
}
/*
** Change the value of the P3 operand for a specific instruction.
*/
void sqlite3VdbeChangeP3(Vdbe *p, int addr, int val){
assert( p!=0 );
assert( addr>=0 );
if( p->nOp>addr ){
p->aOp[addr].p3 = val;
}
}
/*
** Change the value of the P5 operand for the most recently
** added operation.
*/
void sqlite3VdbeChangeP5(Vdbe *p, u8 val){
assert( p!=0 );
if( p->aOp ){
assert( p->nOp>0 );
p->aOp[p->nOp-1].p5 = val;
}
}
/*
** Change the P2 operand of instruction addr so that it points to
** the address of the next instruction to be coded.
*/
void sqlite3VdbeJumpHere(Vdbe *p, int addr){
assert( addr>=0 );
sqlite3VdbeChangeP2(p, addr, p->nOp);
}
/*
** If the input FuncDef structure is ephemeral, then free it. If
** the FuncDef is not ephermal, then do nothing.
*/
static void freeEphemeralFunction(sqlite3 *db, FuncDef *pDef){
if( ALWAYS(pDef) && (pDef->flags & SQLITE_FUNC_EPHEM)!=0 ){
sqlite3DbFree(db, pDef);
}
}
static void vdbeFreeOpArray(sqlite3 *, Op *, int);
/*
** Delete a P4 value if necessary.
*/
static void freeP4(sqlite3 *db, int p4type, void *p4){
if( p4 ){
assert( db );
switch( p4type ){
case P4_REAL:
case P4_INT64:
case P4_DYNAMIC:
case P4_KEYINFO:
case P4_INTARRAY:
case P4_KEYINFO_HANDOFF: {
sqlite3DbFree(db, p4);
break;
}
case P4_MPRINTF: {
if( db->pnBytesFreed==0 ) sqlite3_free(p4);
break;
}
case P4_VDBEFUNC: {
VdbeFunc *pVdbeFunc = (VdbeFunc *)p4;
freeEphemeralFunction(db, pVdbeFunc->pFunc);
if( db->pnBytesFreed==0 ) sqlite3VdbeDeleteAuxData(pVdbeFunc, 0);
sqlite3DbFree(db, pVdbeFunc);
break;
}
case P4_FUNCDEF: {
freeEphemeralFunction(db, (FuncDef*)p4);
break;
}
case P4_MEM: {
if( db->pnBytesFreed==0 ){
sqlite3ValueFree((sqlite3_value*)p4);
}else{
Mem *p = (Mem*)p4;
sqlite3DbFree(db, p->zMalloc);
sqlite3DbFree(db, p);
}
break;
}
case P4_VTAB : {
if( db->pnBytesFreed==0 ) sqlite3VtabUnlock((VTable *)p4);
break;
}
}
}
}
/*
** Free the space allocated for aOp and any p4 values allocated for the
** opcodes contained within. If aOp is not NULL it is assumed to contain
** nOp entries.
*/
static void vdbeFreeOpArray(sqlite3 *db, Op *aOp, int nOp){
if( aOp ){
Op *pOp;
for(pOp=aOp; pOp<&aOp[nOp]; pOp++){
freeP4(db, pOp->p4type, pOp->p4.p);
#ifdef SQLITE_DEBUG
sqlite3DbFree(db, pOp->zComment);
#endif
}
}
sqlite3DbFree(db, aOp);
}
/*
** Link the SubProgram object passed as the second argument into the linked
** list at Vdbe.pSubProgram. This list is used to delete all sub-program
** objects when the VM is no longer required.
*/
void sqlite3VdbeLinkSubProgram(Vdbe *pVdbe, SubProgram *p){
p->pNext = pVdbe->pProgram;
pVdbe->pProgram = p;
}
/*
** Change N opcodes starting at addr to No-ops.
*/
void sqlite3VdbeChangeToNoop(Vdbe *p, int addr, int N){
if( p->aOp ){
VdbeOp *pOp = &p->aOp[addr];
sqlite3 *db = p->db;
while( N-- ){
freeP4(db, pOp->p4type, pOp->p4.p);
memset(pOp, 0, sizeof(pOp[0]));
pOp->opcode = OP_Noop;
pOp++;
}
}
}
/*
** Change the value of the P4 operand for a specific instruction.
** This routine is useful when a large program is loaded from a
** static array using sqlite3VdbeAddOpList but we want to make a
** few minor changes to the program.
**
** If n>=0 then the P4 operand is dynamic, meaning that a copy of
** the string is made into memory obtained from sqlite3_malloc().
** A value of n==0 means copy bytes of zP4 up to and including the
** first null byte. If n>0 then copy n+1 bytes of zP4.
**
** If n==P4_KEYINFO it means that zP4 is a pointer to a KeyInfo structure.
** A copy is made of the KeyInfo structure into memory obtained from
** sqlite3_malloc, to be freed when the Vdbe is finalized.
** n==P4_KEYINFO_HANDOFF indicates that zP4 points to a KeyInfo structure
** stored in memory that the caller has obtained from sqlite3_malloc. The
** caller should not free the allocation, it will be freed when the Vdbe is
** finalized.
**
** Other values of n (P4_STATIC, P4_COLLSEQ etc.) indicate that zP4 points
** to a string or structure that is guaranteed to exist for the lifetime of
** the Vdbe. In these cases we can just copy the pointer.
**
** If addr<0 then change P4 on the most recently inserted instruction.
*/
void sqlite3VdbeChangeP4(Vdbe *p, int addr, const char *zP4, int n){
Op *pOp;
sqlite3 *db;
assert( p!=0 );
db = p->db;
assert( p->magic==VDBE_MAGIC_INIT );
if( p->aOp==0 || db->mallocFailed ){
if ( n!=P4_KEYINFO && n!=P4_VTAB ) {
freeP4(db, n, (void*)*(char**)&zP4);
}
return;
}
assert( p->nOp>0 );
assert( addr<p->nOp );
if( addr<0 ){
addr = p->nOp - 1;
}
pOp = &p->aOp[addr];
freeP4(db, pOp->p4type, pOp->p4.p);
pOp->p4.p = 0;
if( n==P4_INT32 ){
/* Note: this cast is safe, because the origin data point was an int
** that was cast to a (const char *). */
pOp->p4.i = SQLITE_PTR_TO_INT(zP4);
pOp->p4type = P4_INT32;
}else if( zP4==0 ){
pOp->p4.p = 0;
pOp->p4type = P4_NOTUSED;
}else if( n==P4_KEYINFO ){
KeyInfo *pKeyInfo;
int nField, nByte;
nField = ((KeyInfo*)zP4)->nField;
nByte = sizeof(*pKeyInfo) + (nField-1)*sizeof(pKeyInfo->aColl[0]) + nField;
pKeyInfo = sqlite3DbMallocRaw(0, nByte);
pOp->p4.pKeyInfo = pKeyInfo;
if( pKeyInfo ){
u8 *aSortOrder;
memcpy((char*)pKeyInfo, zP4, nByte - nField);
aSortOrder = pKeyInfo->aSortOrder;
if( aSortOrder ){
pKeyInfo->aSortOrder = (unsigned char*)&pKeyInfo->aColl[nField];
memcpy(pKeyInfo->aSortOrder, aSortOrder, nField);
}
pOp->p4type = P4_KEYINFO;
}else{
p->db->mallocFailed = 1;
pOp->p4type = P4_NOTUSED;
}
}else if( n==P4_KEYINFO_HANDOFF ){
pOp->p4.p = (void*)zP4;
pOp->p4type = P4_KEYINFO;
}else if( n==P4_VTAB ){
pOp->p4.p = (void*)zP4;
pOp->p4type = P4_VTAB;
sqlite3VtabLock((VTable *)zP4);
assert( ((VTable *)zP4)->db==p->db );
}else if( n<0 ){
pOp->p4.p = (void*)zP4;
pOp->p4type = (signed char)n;
}else{
if( n==0 ) n = sqlite3Strlen30(zP4);
pOp->p4.z = sqlite3DbStrNDup(p->db, zP4, n);
pOp->p4type = P4_DYNAMIC;
}
}
#ifndef NDEBUG
/*
** Change the comment on the the most recently coded instruction. Or
** insert a No-op and add the comment to that new instruction. This
** makes the code easier to read during debugging. None of this happens
** in a production build.
*/
void sqlite3VdbeComment(Vdbe *p, const char *zFormat, ...){
va_list ap;
if( !p ) return;
assert( p->nOp>0 || p->aOp==0 );
assert( p->aOp==0 || p->aOp[p->nOp-1].zComment==0 || p->db->mallocFailed );
if( p->nOp ){
char **pz = &p->aOp[p->nOp-1].zComment;
va_start(ap, zFormat);
sqlite3DbFree(p->db, *pz);
*pz = sqlite3VMPrintf(p->db, zFormat, ap);
va_end(ap);
}
}
void sqlite3VdbeNoopComment(Vdbe *p, const char *zFormat, ...){
va_list ap;
if( !p ) return;
sqlite3VdbeAddOp0(p, OP_Noop);
assert( p->nOp>0 || p->aOp==0 );
assert( p->aOp==0 || p->aOp[p->nOp-1].zComment==0 || p->db->mallocFailed );
if( p->nOp ){
char **pz = &p->aOp[p->nOp-1].zComment;
va_start(ap, zFormat);
sqlite3DbFree(p->db, *pz);
*pz = sqlite3VMPrintf(p->db, zFormat, ap);
va_end(ap);
}
}
#endif /* NDEBUG */
/*
** Return the opcode for a given address. If the address is -1, then
** return the most recently inserted opcode.
**
** If a memory allocation error has occurred prior to the calling of this
** routine, then a pointer to a dummy VdbeOp will be returned. That opcode
** is readable but not writable, though it is cast to a writable value.
** The return of a dummy opcode allows the call to continue functioning
** after a OOM fault without having to check to see if the return from
** this routine is a valid pointer. But because the dummy.opcode is 0,
** dummy will never be written to. This is verified by code inspection and
** by running with Valgrind.
**
** About the #ifdef SQLITE_OMIT_TRACE: Normally, this routine is never called
** unless p->nOp>0. This is because in the absense of SQLITE_OMIT_TRACE,
** an OP_Trace instruction is always inserted by sqlite3VdbeGet() as soon as
** a new VDBE is created. So we are free to set addr to p->nOp-1 without
** having to double-check to make sure that the result is non-negative. But
** if SQLITE_OMIT_TRACE is defined, the OP_Trace is omitted and we do need to
** check the value of p->nOp-1 before continuing.
*/
VdbeOp *sqlite3VdbeGetOp(Vdbe *p, int addr){
/* C89 specifies that the constant "dummy" will be initialized to all
** zeros, which is correct. MSVC generates a warning, nevertheless. */
static const VdbeOp dummy; /* Ignore the MSVC warning about no initializer */
assert( p->magic==VDBE_MAGIC_INIT );
if( addr<0 ){
#ifdef SQLITE_OMIT_TRACE
if( p->nOp==0 ) return (VdbeOp*)&dummy;
#endif
addr = p->nOp - 1;
}
assert( (addr>=0 && addr<p->nOp) || p->db->mallocFailed );
if( p->db->mallocFailed ){
return (VdbeOp*)&dummy;
}else{
return &p->aOp[addr];
}
}
#if !defined(SQLITE_OMIT_EXPLAIN) || !defined(NDEBUG) \
|| defined(VDBE_PROFILE) || defined(SQLITE_DEBUG)
/*
** Compute a string that describes the P4 parameter for an opcode.
** Use zTemp for any required temporary buffer space.
*/
static char *displayP4(Op *pOp, char *zTemp, int nTemp){
char *zP4 = zTemp;
assert( nTemp>=20 );
switch( pOp->p4type ){
case P4_KEYINFO_STATIC:
case P4_KEYINFO: {
int i, j;
KeyInfo *pKeyInfo = pOp->p4.pKeyInfo;
sqlite3_snprintf(nTemp, zTemp, "keyinfo(%d", pKeyInfo->nField);
i = sqlite3Strlen30(zTemp);
for(j=0; j<pKeyInfo->nField; j++){
CollSeq *pColl = pKeyInfo->aColl[j];
if( pColl ){
int n = sqlite3Strlen30(pColl->zName);
if( i+n>nTemp-6 ){
memcpy(&zTemp[i],",...",4);
break;
}
zTemp[i++] = ',';
if( pKeyInfo->aSortOrder && pKeyInfo->aSortOrder[j] ){
zTemp[i++] = '-';
}
memcpy(&zTemp[i], pColl->zName,n+1);
i += n;
}else if( i+4<nTemp-6 ){
memcpy(&zTemp[i],",nil",4);
i += 4;
}
}
zTemp[i++] = ')';
zTemp[i] = 0;
assert( i<nTemp );
break;
}
case P4_COLLSEQ: {
CollSeq *pColl = pOp->p4.pColl;
sqlite3_snprintf(nTemp, zTemp, "collseq(%.20s)", pColl->zName);
break;
}
case P4_FUNCDEF: {
FuncDef *pDef = pOp->p4.pFunc;
sqlite3_snprintf(nTemp, zTemp, "%s(%d)", pDef->zName, pDef->nArg);
break;
}
case P4_INT64: {
sqlite3_snprintf(nTemp, zTemp, "%lld", *pOp->p4.pI64);
break;
}
case P4_INT32: {
sqlite3_snprintf(nTemp, zTemp, "%d", pOp->p4.i);
break;
}
case P4_REAL: {
sqlite3_snprintf(nTemp, zTemp, "%.16g", *pOp->p4.pReal);
break;
}
case P4_MEM: {
Mem *pMem = pOp->p4.pMem;
assert( (pMem->flags & MEM_Null)==0 );
if( pMem->flags & MEM_Str ){
zP4 = pMem->z;
}else if( pMem->flags & MEM_Int ){
sqlite3_snprintf(nTemp, zTemp, "%lld", pMem->u.i);
}else if( pMem->flags & MEM_Real ){
sqlite3_snprintf(nTemp, zTemp, "%.16g", pMem->r);
}else{
assert( pMem->flags & MEM_Blob );
zP4 = "(blob)";
}
break;
}
#ifndef SQLITE_OMIT_VIRTUALTABLE
case P4_VTAB: {
sqlite3_vtab *pVtab = pOp->p4.pVtab->pVtab;
sqlite3_snprintf(nTemp, zTemp, "vtab:%p:%p", pVtab, pVtab->pModule);
break;
}
#endif
case P4_INTARRAY: {
sqlite3_snprintf(nTemp, zTemp, "intarray");
break;
}
case P4_SUBPROGRAM: {
sqlite3_snprintf(nTemp, zTemp, "program");
break;
}
default: {
zP4 = pOp->p4.z;
if( zP4==0 ){
zP4 = zTemp;
zTemp[0] = 0;
}
}
}
assert( zP4!=0 );
return zP4;
}
#endif
/*
** Declare to the Vdbe that the BTree object at db->aDb[i] is used.
**
** The prepared statements need to know in advance the complete set of
** attached databases that they will be using. A mask of these databases
** is maintained in p->btreeMask and is used for locking and other purposes.
*/
void sqlite3VdbeUsesBtree(Vdbe *p, int i){
assert( i>=0 && i<p->db->nDb && i<(int)sizeof(yDbMask)*8 );
assert( i<(int)sizeof(p->btreeMask)*8 );
p->btreeMask |= ((yDbMask)1)<<i;
if( i!=1 && sqlite3BtreeSharable(p->db->aDb[i].pBt) ){
p->lockMask |= ((yDbMask)1)<<i;
}
}
#if !defined(SQLITE_OMIT_SHARED_CACHE) && SQLITE_THREADSAFE>0
/*
** If SQLite is compiled to support shared-cache mode and to be threadsafe,
** this routine obtains the mutex associated with each BtShared structure
** that may be accessed by the VM passed as an argument. In doing so it also
** sets the BtShared.db member of each of the BtShared structures, ensuring
** that the correct busy-handler callback is invoked if required.
**
** If SQLite is not threadsafe but does support shared-cache mode, then
** sqlite3BtreeEnter() is invoked to set the BtShared.db variables
** of all of BtShared structures accessible via the database handle
** associated with the VM.
**
** If SQLite is not threadsafe and does not support shared-cache mode, this
** function is a no-op.
**
** The p->btreeMask field is a bitmask of all btrees that the prepared
** statement p will ever use. Let N be the number of bits in p->btreeMask
** corresponding to btrees that use shared cache. Then the runtime of
** this routine is N*N. But as N is rarely more than 1, this should not
** be a problem.
*/
void sqlite3VdbeEnter(Vdbe *p){
int i;
yDbMask mask;
sqlite3 *db;
Db *aDb;
int nDb;
if( p->lockMask==0 ) return; /* The common case */
db = p->db;
aDb = db->aDb;
nDb = db->nDb;
for(i=0, mask=1; i<nDb; i++, mask += mask){
if( i!=1 && (mask & p->lockMask)!=0 && ALWAYS(aDb[i].pBt!=0) ){
sqlite3BtreeEnter(aDb[i].pBt);
}
}
}
#endif
#if !defined(SQLITE_OMIT_SHARED_CACHE) && SQLITE_THREADSAFE>0
/*
** Unlock all of the btrees previously locked by a call to sqlite3VdbeEnter().
*/
void sqlite3VdbeLeave(Vdbe *p){
int i;
yDbMask mask;
sqlite3 *db;
Db *aDb;
int nDb;
if( p->lockMask==0 ) return; /* The common case */
db = p->db;
aDb = db->aDb;
nDb = db->nDb;
for(i=0, mask=1; i<nDb; i++, mask += mask){
if( i!=1 && (mask & p->lockMask)!=0 && ALWAYS(aDb[i].pBt!=0) ){
sqlite3BtreeLeave(aDb[i].pBt);
}
}
}
#endif
#if defined(VDBE_PROFILE) || defined(SQLITE_DEBUG)
/*
** Print a single opcode. This routine is used for debugging only.
*/
void sqlite3VdbePrintOp(FILE *pOut, int pc, Op *pOp){
char *zP4;
char zPtr[50];
static const char *zFormat1 = "%4d %-13s %4d %4d %4d %-4s %.2X %s\n";
if( pOut==0 ) pOut = stdout;
zP4 = displayP4(pOp, zPtr, sizeof(zPtr));
fprintf(pOut, zFormat1, pc,
sqlite3OpcodeName(pOp->opcode), pOp->p1, pOp->p2, pOp->p3, zP4, pOp->p5,
#ifdef SQLITE_DEBUG
pOp->zComment ? pOp->zComment : ""
#else
""
#endif
);
fflush(pOut);
}
#endif
/*
** Release an array of N Mem elements
*/
static void releaseMemArray(Mem *p, int N){
if( p && N ){
Mem *pEnd;
sqlite3 *db = p->db;
u8 malloc_failed = db->mallocFailed;
if( db->pnBytesFreed ){
for(pEnd=&p[N]; p<pEnd; p++){
sqlite3DbFree(db, p->zMalloc);
}
return;
}
for(pEnd=&p[N]; p<pEnd; p++){
assert( (&p[1])==pEnd || p[0].db==p[1].db );
/* This block is really an inlined version of sqlite3VdbeMemRelease()
** that takes advantage of the fact that the memory cell value is
** being set to NULL after releasing any dynamic resources.
**
** The justification for duplicating code is that according to
** callgrind, this causes a certain test case to hit the CPU 4.7
** percent less (x86 linux, gcc version 4.1.2, -O6) than if
** sqlite3MemRelease() were called from here. With -O2, this jumps
** to 6.6 percent. The test case is inserting 1000 rows into a table
** with no indexes using a single prepared INSERT statement, bind()
** and reset(). Inserts are grouped into a transaction.
*/
if( p->flags&(MEM_Agg|MEM_Dyn|MEM_Frame|MEM_RowSet) ){
sqlite3VdbeMemRelease(p);
}else if( p->zMalloc ){
sqlite3DbFree(db, p->zMalloc);
p->zMalloc = 0;
}
p->flags = MEM_Null;
}
db->mallocFailed = malloc_failed;
}
}
/*
** Delete a VdbeFrame object and its contents. VdbeFrame objects are
** allocated by the OP_Program opcode in sqlite3VdbeExec().
*/
void sqlite3VdbeFrameDelete(VdbeFrame *p){
int i;
Mem *aMem = VdbeFrameMem(p);
VdbeCursor **apCsr = (VdbeCursor **)&aMem[p->nChildMem];
for(i=0; i<p->nChildCsr; i++){
sqlite3VdbeFreeCursor(p->v, apCsr[i]);
}
releaseMemArray(aMem, p->nChildMem);
sqlite3DbFree(p->v->db, p);
}
#ifndef SQLITE_OMIT_EXPLAIN
/*
** Give a listing of the program in the virtual machine.
**
** The interface is the same as sqlite3VdbeExec(). But instead of
** running the code, it invokes the callback once for each instruction.
** This feature is used to implement "EXPLAIN".
**
** When p->explain==1, each instruction is listed. When
** p->explain==2, only OP_Explain instructions are listed and these
** are shown in a different format. p->explain==2 is used to implement
** EXPLAIN QUERY PLAN.
**
** When p->explain==1, first the main program is listed, then each of
** the trigger subprograms are listed one by one.
*/
int sqlite3VdbeList(
Vdbe *p /* The VDBE */
){
int nRow; /* Stop when row count reaches this */
int nSub = 0; /* Number of sub-vdbes seen so far */
SubProgram **apSub = 0; /* Array of sub-vdbes */
Mem *pSub = 0; /* Memory cell hold array of subprogs */
sqlite3 *db = p->db; /* The database connection */
int i; /* Loop counter */
int rc = SQLITE_OK; /* Return code */
Mem *pMem = p->pResultSet = &p->aMem[1]; /* First Mem of result set */
assert( p->explain );
assert( p->magic==VDBE_MAGIC_RUN );
assert( p->rc==SQLITE_OK || p->rc==SQLITE_BUSY || p->rc==SQLITE_NOMEM );
/* Even though this opcode does not use dynamic strings for
** the result, result columns may become dynamic if the user calls
** sqlite3_column_text16(), causing a translation to UTF-16 encoding.
*/
releaseMemArray(pMem, 8);
if( p->rc==SQLITE_NOMEM ){
/* This happens if a malloc() inside a call to sqlite3_column_text() or
** sqlite3_column_text16() failed. */
db->mallocFailed = 1;
return SQLITE_ERROR;
}
/* When the number of output rows reaches nRow, that means the
** listing has finished and sqlite3_step() should return SQLITE_DONE.
** nRow is the sum of the number of rows in the main program, plus
** the sum of the number of rows in all trigger subprograms encountered
** so far. The nRow value will increase as new trigger subprograms are
** encountered, but p->pc will eventually catch up to nRow.
*/
nRow = p->nOp;
if( p->explain==1 ){
/* The first 8 memory cells are used for the result set. So we will
** commandeer the 9th cell to use as storage for an array of pointers
** to trigger subprograms. The VDBE is guaranteed to have at least 9
** cells. */
assert( p->nMem>9 );
pSub = &p->aMem[9];
if( pSub->flags&MEM_Blob ){
/* On the first call to sqlite3_step(), pSub will hold a NULL. It is
** initialized to a BLOB by the P4_SUBPROGRAM processing logic below */
nSub = pSub->n/sizeof(Vdbe*);
apSub = (SubProgram **)pSub->z;
}
for(i=0; i<nSub; i++){
nRow += apSub[i]->nOp;
}
}
do{
i = p->pc++;
}while( i<nRow && p->explain==2 && p->aOp[i].opcode!=OP_Explain );
if( i>=nRow ){
p->rc = SQLITE_OK;
rc = SQLITE_DONE;
}else if( db->u1.isInterrupted ){
p->rc = SQLITE_INTERRUPT;
rc = SQLITE_ERROR;
sqlite3SetString(&p->zErrMsg, db, "%s", sqlite3ErrStr(p->rc));
}else{
char *z;
Op *pOp;
if( i<p->nOp ){
/* The output line number is small enough that we are still in the
** main program. */
pOp = &p->aOp[i];
}else{
/* We are currently listing subprograms. Figure out which one and
** pick up the appropriate opcode. */
int j;
i -= p->nOp;
for(j=0; i>=apSub[j]->nOp; j++){
i -= apSub[j]->nOp;
}
pOp = &apSub[j]->aOp[i];
}
if( p->explain==1 ){
pMem->flags = MEM_Int;
pMem->type = SQLITE_INTEGER;
pMem->u.i = i; /* Program counter */
pMem++;
pMem->flags = MEM_Static|MEM_Str|MEM_Term;
pMem->z = (char*)sqlite3OpcodeName(pOp->opcode); /* Opcode */
assert( pMem->z!=0 );
pMem->n = sqlite3Strlen30(pMem->z);
pMem->type = SQLITE_TEXT;
pMem->enc = SQLITE_UTF8;
pMem++;
/* When an OP_Program opcode is encounter (the only opcode that has
** a P4_SUBPROGRAM argument), expand the size of the array of subprograms
** kept in p->aMem[9].z to hold the new program - assuming this subprogram
** has not already been seen.
*/
if( pOp->p4type==P4_SUBPROGRAM ){
int nByte = (nSub+1)*sizeof(SubProgram*);
int j;
for(j=0; j<nSub; j++){
if( apSub[j]==pOp->p4.pProgram ) break;
}
if( j==nSub && SQLITE_OK==sqlite3VdbeMemGrow(pSub, nByte, 1) ){
apSub = (SubProgram **)pSub->z;
apSub[nSub++] = pOp->p4.pProgram;
pSub->flags |= MEM_Blob;
pSub->n = nSub*sizeof(SubProgram*);
}
}
}
pMem->flags = MEM_Int;
pMem->u.i = pOp->p1; /* P1 */
pMem->type = SQLITE_INTEGER;
pMem++;
pMem->flags = MEM_Int;
pMem->u.i = pOp->p2; /* P2 */
pMem->type = SQLITE_INTEGER;
pMem++;
pMem->flags = MEM_Int;
pMem->u.i = pOp->p3; /* P3 */
pMem->type = SQLITE_INTEGER;
pMem++;
if( sqlite3VdbeMemGrow(pMem, 32, 0) ){ /* P4 */
assert( p->db->mallocFailed );
return SQLITE_ERROR;
}
pMem->flags = MEM_Dyn|MEM_Str|MEM_Term;
z = displayP4(pOp, pMem->z, 32);
if( z!=pMem->z ){
sqlite3VdbeMemSetStr(pMem, z, -1, SQLITE_UTF8, 0);
}else{
assert( pMem->z!=0 );
pMem->n = sqlite3Strlen30(pMem->z);
pMem->enc = SQLITE_UTF8;
}
pMem->type = SQLITE_TEXT;
pMem++;
if( p->explain==1 ){
if( sqlite3VdbeMemGrow(pMem, 4, 0) ){
assert( p->db->mallocFailed );
return SQLITE_ERROR;
}
pMem->flags = MEM_Dyn|MEM_Str|MEM_Term;
pMem->n = 2;
sqlite3_snprintf(3, pMem->z, "%.2x", pOp->p5); /* P5 */
pMem->type = SQLITE_TEXT;
pMem->enc = SQLITE_UTF8;
pMem++;
#ifdef SQLITE_DEBUG
if( pOp->zComment ){
pMem->flags = MEM_Str|MEM_Term;
pMem->z = pOp->zComment;
pMem->n = sqlite3Strlen30(pMem->z);
pMem->enc = SQLITE_UTF8;
pMem->type = SQLITE_TEXT;
}else
#endif
{
pMem->flags = MEM_Null; /* Comment */
pMem->type = SQLITE_NULL;
}
}
p->nResColumn = 8 - 4*(p->explain-1);
p->rc = SQLITE_OK;
rc = SQLITE_ROW;
}
return rc;
}
#endif /* SQLITE_OMIT_EXPLAIN */
#ifdef SQLITE_DEBUG
/*
** Print the SQL that was used to generate a VDBE program.
*/
void sqlite3VdbePrintSql(Vdbe *p){
int nOp = p->nOp;
VdbeOp *pOp;
if( nOp<1 ) return;
pOp = &p->aOp[0];
if( pOp->opcode==OP_Trace && pOp->p4.z!=0 ){
const char *z = pOp->p4.z;
while( sqlite3Isspace(*z) ) z++;
printf("SQL: [%s]\n", z);
}
}
#endif
#if !defined(SQLITE_OMIT_TRACE) && defined(SQLITE_ENABLE_IOTRACE)
/*
** Print an IOTRACE message showing SQL content.
*/
void sqlite3VdbeIOTraceSql(Vdbe *p){
int nOp = p->nOp;
VdbeOp *pOp;
if( sqlite3IoTrace==0 ) return;
if( nOp<1 ) return;
pOp = &p->aOp[0];
if( pOp->opcode==OP_Trace && pOp->p4.z!=0 ){
int i, j;
char z[1000];
sqlite3_snprintf(sizeof(z), z, "%s", pOp->p4.z);
for(i=0; sqlite3Isspace(z[i]); i++){}
for(j=0; z[i]; i++){
if( sqlite3Isspace(z[i]) ){
if( z[i-1]!=' ' ){
z[j++] = ' ';
}
}else{
z[j++] = z[i];
}
}
z[j] = 0;
sqlite3IoTrace("SQL %s\n", z);
}
}
#endif /* !SQLITE_OMIT_TRACE && SQLITE_ENABLE_IOTRACE */
/*
** Allocate space from a fixed size buffer and return a pointer to
** that space. If insufficient space is available, return NULL.
**
** The pBuf parameter is the initial value of a pointer which will
** receive the new memory. pBuf is normally NULL. If pBuf is not
** NULL, it means that memory space has already been allocated and that
** this routine should not allocate any new memory. When pBuf is not
** NULL simply return pBuf. Only allocate new memory space when pBuf
** is NULL.
**
** nByte is the number of bytes of space needed.
**
** *ppFrom points to available space and pEnd points to the end of the
** available space. When space is allocated, *ppFrom is advanced past
** the end of the allocated space.
**
** *pnByte is a counter of the number of bytes of space that have failed
** to allocate. If there is insufficient space in *ppFrom to satisfy the
** request, then increment *pnByte by the amount of the request.
*/
static void *allocSpace(
void *pBuf, /* Where return pointer will be stored */
int nByte, /* Number of bytes to allocate */
u8 **ppFrom, /* IN/OUT: Allocate from *ppFrom */
u8 *pEnd, /* Pointer to 1 byte past the end of *ppFrom buffer */
int *pnByte /* If allocation cannot be made, increment *pnByte */
){
assert( EIGHT_BYTE_ALIGNMENT(*ppFrom) );
if( pBuf ) return pBuf;
nByte = ROUND8(nByte);
if( &(*ppFrom)[nByte] <= pEnd ){
pBuf = (void*)*ppFrom;
*ppFrom += nByte;
}else{
*pnByte += nByte;
}
return pBuf;
}
/*
** Prepare a virtual machine for execution. This involves things such
** as allocating stack space and initializing the program counter.
** After the VDBE has be prepped, it can be executed by one or more
** calls to sqlite3VdbeExec().
**
** This is the only way to move a VDBE from VDBE_MAGIC_INIT to
** VDBE_MAGIC_RUN.
**
** This function may be called more than once on a single virtual machine.
** The first call is made while compiling the SQL statement. Subsequent
** calls are made as part of the process of resetting a statement to be
** re-executed (from a call to sqlite3_reset()). The nVar, nMem, nCursor
** and isExplain parameters are only passed correct values the first time
** the function is called. On subsequent calls, from sqlite3_reset(), nVar
** is passed -1 and nMem, nCursor and isExplain are all passed zero.
*/
void sqlite3VdbeMakeReady(
Vdbe *p, /* The VDBE */
int nVar, /* Number of '?' see in the SQL statement */
int nMem, /* Number of memory cells to allocate */
int nCursor, /* Number of cursors to allocate */
int nArg, /* Maximum number of args in SubPrograms */
int isExplain, /* True if the EXPLAIN keywords is present */
int usesStmtJournal /* True to set Vdbe.usesStmtJournal */
){
int n;
sqlite3 *db = p->db;
assert( p!=0 );
assert( p->magic==VDBE_MAGIC_INIT );
/* There should be at least one opcode.
*/
assert( p->nOp>0 );
/* Set the magic to VDBE_MAGIC_RUN sooner rather than later. */
p->magic = VDBE_MAGIC_RUN;
/* For each cursor required, also allocate a memory cell. Memory
** cells (nMem+1-nCursor)..nMem, inclusive, will never be used by
** the vdbe program. Instead they are used to allocate space for
** VdbeCursor/BtCursor structures. The blob of memory associated with
** cursor 0 is stored in memory cell nMem. Memory cell (nMem-1)
** stores the blob of memory associated with cursor 1, etc.
**
** See also: allocateCursor().
*/
nMem += nCursor;
/* Allocate space for memory registers, SQL variables, VDBE cursors and
** an array to marshal SQL function arguments in. This is only done the
** first time this function is called for a given VDBE, not when it is
** being called from sqlite3_reset() to reset the virtual machine.
*/
if( nVar>=0 && ALWAYS(db->mallocFailed==0) ){
u8 *zCsr = (u8 *)&p->aOp[p->nOp]; /* Memory avaliable for alloation */
u8 *zEnd = (u8 *)&p->aOp[p->nOpAlloc]; /* First byte past available mem */
int nByte; /* How much extra memory needed */
resolveP2Values(p, &nArg);
p->usesStmtJournal = (u8)usesStmtJournal;
if( isExplain && nMem<10 ){
nMem = 10;
}
memset(zCsr, 0, zEnd-zCsr);
zCsr += (zCsr - (u8*)0)&7;
assert( EIGHT_BYTE_ALIGNMENT(zCsr) );
/* Memory for registers, parameters, cursor, etc, is allocated in two
** passes. On the first pass, we try to reuse unused space at the
** end of the opcode array. If we are unable to satisfy all memory
** requirements by reusing the opcode array tail, then the second
** pass will fill in the rest using a fresh allocation.
**
** This two-pass approach that reuses as much memory as possible from
** the leftover space at the end of the opcode array can significantly
** reduce the amount of memory held by a prepared statement.
*/
do {
nByte = 0;
p->aMem = allocSpace(p->aMem, nMem*sizeof(Mem), &zCsr, zEnd, &nByte);
p->aVar = allocSpace(p->aVar, nVar*sizeof(Mem), &zCsr, zEnd, &nByte);
p->apArg = allocSpace(p->apArg, nArg*sizeof(Mem*), &zCsr, zEnd, &nByte);
p->azVar = allocSpace(p->azVar, nVar*sizeof(char*), &zCsr, zEnd, &nByte);
p->apCsr = allocSpace(p->apCsr, nCursor*sizeof(VdbeCursor*),
&zCsr, zEnd, &nByte);
if( nByte ){
p->pFree = sqlite3DbMallocZero(db, nByte);
}
zCsr = p->pFree;
zEnd = &zCsr[nByte];
}while( nByte && !db->mallocFailed );
p->nCursor = (u16)nCursor;
if( p->aVar ){
p->nVar = (ynVar)nVar;
for(n=0; n<nVar; n++){
p->aVar[n].flags = MEM_Null;
p->aVar[n].db = db;
}
}
if( p->aMem ){
p->aMem--; /* aMem[] goes from 1..nMem */
p->nMem = nMem; /* not from 0..nMem-1 */
for(n=1; n<=nMem; n++){
p->aMem[n].flags = MEM_Null;
p->aMem[n].db = db;
}
}
}
#ifdef SQLITE_DEBUG
for(n=1; n<p->nMem; n++){
assert( p->aMem[n].db==db );
}
#endif
p->pc = -1;
p->rc = SQLITE_OK;
p->errorAction = OE_Abort;
p->explain |= isExplain;
p->magic = VDBE_MAGIC_RUN;
p->nChange = 0;
p->cacheCtr = 1;
p->minWriteFileFormat = 255;
p->iStatement = 0;
p->nFkConstraint = 0;
#ifdef VDBE_PROFILE
{
int i;
for(i=0; i<p->nOp; i++){
p->aOp[i].cnt = 0;
p->aOp[i].cycles = 0;
}
}
#endif
}
/*
** Close a VDBE cursor and release all the resources that cursor
** happens to hold.
*/
void sqlite3VdbeFreeCursor(Vdbe *p, VdbeCursor *pCx){
if( pCx==0 ){
return;
}
if( pCx->pBt ){
sqlite3BtreeClose(pCx->pBt);
/* The pCx->pCursor will be close automatically, if it exists, by
** the call above. */
}else if( pCx->pCursor ){
sqlite3BtreeCloseCursor(pCx->pCursor);
}
#ifndef SQLITE_OMIT_VIRTUALTABLE
if( pCx->pVtabCursor ){
sqlite3_vtab_cursor *pVtabCursor = pCx->pVtabCursor;
const sqlite3_module *pModule = pCx->pModule;
p->inVtabMethod = 1;
pModule->xClose(pVtabCursor);
p->inVtabMethod = 0;
}
#endif
}
/*
** Copy the values stored in the VdbeFrame structure to its Vdbe. This
** is used, for example, when a trigger sub-program is halted to restore
** control to the main program.
*/
int sqlite3VdbeFrameRestore(VdbeFrame *pFrame){
Vdbe *v = pFrame->v;
v->aOp = pFrame->aOp;
v->nOp = pFrame->nOp;
v->aMem = pFrame->aMem;
v->nMem = pFrame->nMem;
v->apCsr = pFrame->apCsr;
v->nCursor = pFrame->nCursor;
v->db->lastRowid = pFrame->lastRowid;
v->nChange = pFrame->nChange;
return pFrame->pc;
}
/*
** Close all cursors.
**
** Also release any dynamic memory held by the VM in the Vdbe.aMem memory
** cell array. This is necessary as the memory cell array may contain
** pointers to VdbeFrame objects, which may in turn contain pointers to
** open cursors.
*/
static void closeAllCursors(Vdbe *p){
if( p->pFrame ){
VdbeFrame *pFrame;
for(pFrame=p->pFrame; pFrame->pParent; pFrame=pFrame->pParent);
sqlite3VdbeFrameRestore(pFrame);
}
p->pFrame = 0;
p->nFrame = 0;
if( p->apCsr ){
int i;
for(i=0; i<p->nCursor; i++){
VdbeCursor *pC = p->apCsr[i];
if( pC ){
sqlite3VdbeFreeCursor(p, pC);
p->apCsr[i] = 0;
}
}
}
if( p->aMem ){
releaseMemArray(&p->aMem[1], p->nMem);
}
while( p->pDelFrame ){
VdbeFrame *pDel = p->pDelFrame;
p->pDelFrame = pDel->pParent;
sqlite3VdbeFrameDelete(pDel);
}
}
/*
** Clean up the VM after execution.
**
** This routine will automatically close any cursors, lists, and/or
** sorters that were left open. It also deletes the values of
** variables in the aVar[] array.
*/
static void Cleanup(Vdbe *p){
sqlite3 *db = p->db;
#ifdef SQLITE_DEBUG
/* Execute assert() statements to ensure that the Vdbe.apCsr[] and
** Vdbe.aMem[] arrays have already been cleaned up. */
int i;
for(i=0; i<p->nCursor; i++) assert( p->apCsr==0 || p->apCsr[i]==0 );
for(i=1; i<=p->nMem; i++) assert( p->aMem==0 || p->aMem[i].flags==MEM_Null );
#endif
sqlite3DbFree(db, p->zErrMsg);
p->zErrMsg = 0;
p->pResultSet = 0;
}
/*
** Set the number of result columns that will be returned by this SQL
** statement. This is now set at compile time, rather than during
** execution of the vdbe program so that sqlite3_column_count() can
** be called on an SQL statement before sqlite3_step().
*/
void sqlite3VdbeSetNumCols(Vdbe *p, int nResColumn){
Mem *pColName;
int n;
sqlite3 *db = p->db;
releaseMemArray(p->aColName, p->nResColumn*COLNAME_N);
sqlite3DbFree(db, p->aColName);
n = nResColumn*COLNAME_N;
p->nResColumn = (u16)nResColumn;
p->aColName = pColName = (Mem*)sqlite3DbMallocZero(db, sizeof(Mem)*n );
if( p->aColName==0 ) return;
while( n-- > 0 ){
pColName->flags = MEM_Null;
pColName->db = p->db;
pColName++;
}
}
/*
** Set the name of the idx'th column to be returned by the SQL statement.
** zName must be a pointer to a nul terminated string.
**
** This call must be made after a call to sqlite3VdbeSetNumCols().
**
** The final parameter, xDel, must be one of SQLITE_DYNAMIC, SQLITE_STATIC
** or SQLITE_TRANSIENT. If it is SQLITE_DYNAMIC, then the buffer pointed
** to by zName will be freed by sqlite3DbFree() when the vdbe is destroyed.
*/
int sqlite3VdbeSetColName(
Vdbe *p, /* Vdbe being configured */
int idx, /* Index of column zName applies to */
int var, /* One of the COLNAME_* constants */
const char *zName, /* Pointer to buffer containing name */
void (*xDel)(void*) /* Memory management strategy for zName */
){
int rc;
Mem *pColName;
assert( idx<p->nResColumn );
assert( var<COLNAME_N );
if( p->db->mallocFailed ){
assert( !zName || xDel!=SQLITE_DYNAMIC );
return SQLITE_NOMEM;
}
assert( p->aColName!=0 );
pColName = &(p->aColName[idx+var*p->nResColumn]);
rc = sqlite3VdbeMemSetStr(pColName, zName, -1, SQLITE_UTF8, xDel);
assert( rc!=0 || !zName || (pColName->flags&MEM_Term)!=0 );
return rc;
}
/*
** A read or write transaction may or may not be active on database handle
** db. If a transaction is active, commit it. If there is a
** write-transaction spanning more than one database file, this routine
** takes care of the master journal trickery.
*/
static int vdbeCommit(sqlite3 *db, Vdbe *p){
int i;
int nTrans = 0; /* Number of databases with an active write-transaction */
int rc = SQLITE_OK;
int needXcommit = 0;
#ifdef SQLITE_OMIT_VIRTUALTABLE
/* With this option, sqlite3VtabSync() is defined to be simply
** SQLITE_OK so p is not used.
*/
UNUSED_PARAMETER(p);
#endif
/* Before doing anything else, call the xSync() callback for any
** virtual module tables written in this transaction. This has to
** be done before determining whether a master journal file is
** required, as an xSync() callback may add an attached database
** to the transaction.
*/
rc = sqlite3VtabSync(db, &p->zErrMsg);
/* This loop determines (a) if the commit hook should be invoked and
** (b) how many database files have open write transactions, not
** including the temp database. (b) is important because if more than
** one database file has an open write transaction, a master journal
** file is required for an atomic commit.
*/
for(i=0; rc==SQLITE_OK && i<db->nDb; i++){
Btree *pBt = db->aDb[i].pBt;
if( sqlite3BtreeIsInTrans(pBt) ){
needXcommit = 1;
if( i!=1 ) nTrans++;
rc = sqlite3PagerExclusiveLock(sqlite3BtreePager(pBt));
}
}
if( rc!=SQLITE_OK ){
return rc;
}
/* If there are any write-transactions at all, invoke the commit hook */
if( needXcommit && db->xCommitCallback ){
rc = db->xCommitCallback(db->pCommitArg);
if( rc ){
return SQLITE_CONSTRAINT;
}
}
/* The simple case - no more than one database file (not counting the
** TEMP database) has a transaction active. There is no need for the
** master-journal.
**
** If the return value of sqlite3BtreeGetFilename() is a zero length
** string, it means the main database is :memory: or a temp file. In
** that case we do not support atomic multi-file commits, so use the
** simple case then too.
*/
if( 0==sqlite3Strlen30(sqlite3BtreeGetFilename(db->aDb[0].pBt))
|| nTrans<=1
){
for(i=0; rc==SQLITE_OK && i<db->nDb; i++){
Btree *pBt = db->aDb[i].pBt;
if( pBt ){
rc = sqlite3BtreeCommitPhaseOne(pBt, 0);
}
}
/* Do the commit only if all databases successfully complete phase 1.
** If one of the BtreeCommitPhaseOne() calls fails, this indicates an
** IO error while deleting or truncating a journal file. It is unlikely,
** but could happen. In this case abandon processing and return the error.
*/
for(i=0; rc==SQLITE_OK && i<db->nDb; i++){
Btree *pBt = db->aDb[i].pBt;
if( pBt ){
rc = sqlite3BtreeCommitPhaseTwo(pBt, 0);
}
}
if( rc==SQLITE_OK ){
sqlite3VtabCommit(db);
}
}
/* The complex case - There is a multi-file write-transaction active.
** This requires a master journal file to ensure the transaction is
** committed atomicly.
*/
#ifndef SQLITE_OMIT_DISKIO
else{
sqlite3_vfs *pVfs = db->pVfs;
int needSync = 0;
char *zMaster = 0; /* File-name for the master journal */
char const *zMainFile = sqlite3BtreeGetFilename(db->aDb[0].pBt);
sqlite3_file *pMaster = 0;
i64 offset = 0;
int res;
/* Select a master journal file name */
do {
u32 iRandom;
sqlite3DbFree(db, zMaster);
sqlite3_randomness(sizeof(iRandom), &iRandom);
zMaster = sqlite3MPrintf(db, "%s-mj%08X", zMainFile, iRandom&0x7fffffff);
if( !zMaster ){
return SQLITE_NOMEM;
}
rc = sqlite3OsAccess(pVfs, zMaster, SQLITE_ACCESS_EXISTS, &res);
}while( rc==SQLITE_OK && res );
if( rc==SQLITE_OK ){
/* Open the master journal. */
rc = sqlite3OsOpenMalloc(pVfs, zMaster, &pMaster,
SQLITE_OPEN_READWRITE|SQLITE_OPEN_CREATE|
SQLITE_OPEN_EXCLUSIVE|SQLITE_OPEN_MASTER_JOURNAL, 0
);
}
if( rc!=SQLITE_OK ){
sqlite3DbFree(db, zMaster);
return rc;
}
/* Write the name of each database file in the transaction into the new
** master journal file. If an error occurs at this point close
** and delete the master journal file. All the individual journal files
** still have 'null' as the master journal pointer, so they will roll
** back independently if a failure occurs.
*/
for(i=0; i<db->nDb; i++){
Btree *pBt = db->aDb[i].pBt;
if( sqlite3BtreeIsInTrans(pBt) ){
char const *zFile = sqlite3BtreeGetJournalname(pBt);
if( zFile==0 ){
continue; /* Ignore TEMP and :memory: databases */
}
assert( zFile[0]!=0 );
if( !needSync && !sqlite3BtreeSyncDisabled(pBt) ){
needSync = 1;
}
rc = sqlite3OsWrite(pMaster, zFile, sqlite3Strlen30(zFile)+1, offset);
offset += sqlite3Strlen30(zFile)+1;
if( rc!=SQLITE_OK ){
sqlite3OsCloseFree(pMaster);
sqlite3OsDelete(pVfs, zMaster, 0);
sqlite3DbFree(db, zMaster);
return rc;
}
}
}
/* Sync the master journal file. If the IOCAP_SEQUENTIAL device
** flag is set this is not required.
*/
if( needSync
&& 0==(sqlite3OsDeviceCharacteristics(pMaster)&SQLITE_IOCAP_SEQUENTIAL)
&& SQLITE_OK!=(rc = sqlite3OsSync(pMaster, SQLITE_SYNC_NORMAL))
){
sqlite3OsCloseFree(pMaster);
sqlite3OsDelete(pVfs, zMaster, 0);
sqlite3DbFree(db, zMaster);
return rc;
}
/* Sync all the db files involved in the transaction. The same call
** sets the master journal pointer in each individual journal. If
** an error occurs here, do not delete the master journal file.
**
** If the error occurs during the first call to
** sqlite3BtreeCommitPhaseOne(), then there is a chance that the
** master journal file will be orphaned. But we cannot delete it,
** in case the master journal file name was written into the journal
** file before the failure occurred.
*/
for(i=0; rc==SQLITE_OK && i<db->nDb; i++){
Btree *pBt = db->aDb[i].pBt;
if( pBt ){
rc = sqlite3BtreeCommitPhaseOne(pBt, zMaster);
}
}
sqlite3OsCloseFree(pMaster);
assert( rc!=SQLITE_BUSY );
if( rc!=SQLITE_OK ){
sqlite3DbFree(db, zMaster);
return rc;
}
/* Delete the master journal file. This commits the transaction. After
** doing this the directory is synced again before any individual
** transaction files are deleted.
*/
rc = sqlite3OsDelete(pVfs, zMaster, 1);
sqlite3DbFree(db, zMaster);
zMaster = 0;
if( rc ){
return rc;
}
/* All files and directories have already been synced, so the following
** calls to sqlite3BtreeCommitPhaseTwo() are only closing files and
** deleting or truncating journals. If something goes wrong while
** this is happening we don't really care. The integrity of the
** transaction is already guaranteed, but some stray 'cold' journals
** may be lying around. Returning an error code won't help matters.
*/
disable_simulated_io_errors();
sqlite3BeginBenignMalloc();
for(i=0; i<db->nDb; i++){
Btree *pBt = db->aDb[i].pBt;
if( pBt ){
sqlite3BtreeCommitPhaseTwo(pBt, 1);
}
}
sqlite3EndBenignMalloc();
enable_simulated_io_errors();
sqlite3VtabCommit(db);
}
#endif
return rc;
}
/*
** This routine checks that the sqlite3.activeVdbeCnt count variable
** matches the number of vdbe's in the list sqlite3.pVdbe that are
** currently active. An assertion fails if the two counts do not match.
** This is an internal self-check only - it is not an essential processing
** step.
**
** This is a no-op if NDEBUG is defined.
*/
#ifndef NDEBUG
static void checkActiveVdbeCnt(sqlite3 *db){
Vdbe *p;
int cnt = 0;
int nWrite = 0;
p = db->pVdbe;
while( p ){
if( p->magic==VDBE_MAGIC_RUN && p->pc>=0 ){
cnt++;
if( p->readOnly==0 ) nWrite++;
}
p = p->pNext;
}
assert( cnt==db->activeVdbeCnt );
assert( nWrite==db->writeVdbeCnt );
}
#else
#define checkActiveVdbeCnt(x)
#endif
/*
** For every Btree that in database connection db which
** has been modified, "trip" or invalidate each cursor in
** that Btree might have been modified so that the cursor
** can never be used again. This happens when a rollback
*** occurs. We have to trip all the other cursors, even
** cursor from other VMs in different database connections,
** so that none of them try to use the data at which they
** were pointing and which now may have been changed due
** to the rollback.
**
** Remember that a rollback can delete tables complete and
** reorder rootpages. So it is not sufficient just to save
** the state of the cursor. We have to invalidate the cursor
** so that it is never used again.
*/
static void invalidateCursorsOnModifiedBtrees(sqlite3 *db){
int i;
for(i=0; i<db->nDb; i++){
Btree *p = db->aDb[i].pBt;
if( p && sqlite3BtreeIsInTrans(p) ){
sqlite3BtreeTripAllCursors(p, SQLITE_ABORT);
}
}
}
/*
** If the Vdbe passed as the first argument opened a statement-transaction,
** close it now. Argument eOp must be either SAVEPOINT_ROLLBACK or
** SAVEPOINT_RELEASE. If it is SAVEPOINT_ROLLBACK, then the statement
** transaction is rolled back. If eOp is SAVEPOINT_RELEASE, then the
** statement transaction is commtted.
**
** If an IO error occurs, an SQLITE_IOERR_XXX error code is returned.
** Otherwise SQLITE_OK.
*/
int sqlite3VdbeCloseStatement(Vdbe *p, int eOp){
sqlite3 *const db = p->db;
int rc = SQLITE_OK;
/* If p->iStatement is greater than zero, then this Vdbe opened a
** statement transaction that should be closed here. The only exception
** is that an IO error may have occured, causing an emergency rollback.
** In this case (db->nStatement==0), and there is nothing to do.
*/
if( db->nStatement && p->iStatement ){
int i;
const int iSavepoint = p->iStatement-1;
assert( eOp==SAVEPOINT_ROLLBACK || eOp==SAVEPOINT_RELEASE);
assert( db->nStatement>0 );
assert( p->iStatement==(db->nStatement+db->nSavepoint) );
for(i=0; i<db->nDb; i++){
int rc2 = SQLITE_OK;
Btree *pBt = db->aDb[i].pBt;
if( pBt ){
if( eOp==SAVEPOINT_ROLLBACK ){
rc2 = sqlite3BtreeSavepoint(pBt, SAVEPOINT_ROLLBACK, iSavepoint);
}
if( rc2==SQLITE_OK ){
rc2 = sqlite3BtreeSavepoint(pBt, SAVEPOINT_RELEASE, iSavepoint);
}
if( rc==SQLITE_OK ){
rc = rc2;
}
}
}
db->nStatement--;
p->iStatement = 0;
/* If the statement transaction is being rolled back, also restore the
** database handles deferred constraint counter to the value it had when
** the statement transaction was opened. */
if( eOp==SAVEPOINT_ROLLBACK ){
db->nDeferredCons = p->nStmtDefCons;
}
}
return rc;
}
/*
** This function is called when a transaction opened by the database
** handle associated with the VM passed as an argument is about to be
** committed. If there are outstanding deferred foreign key constraint
** violations, return SQLITE_ERROR. Otherwise, SQLITE_OK.
**
** If there are outstanding FK violations and this function returns
** SQLITE_ERROR, set the result of the VM to SQLITE_CONSTRAINT and write
** an error message to it. Then return SQLITE_ERROR.
*/
#ifndef SQLITE_OMIT_FOREIGN_KEY
int sqlite3VdbeCheckFk(Vdbe *p, int deferred){
sqlite3 *db = p->db;
if( (deferred && db->nDeferredCons>0) || (!deferred && p->nFkConstraint>0) ){
p->rc = SQLITE_CONSTRAINT;
p->errorAction = OE_Abort;
sqlite3SetString(&p->zErrMsg, db, "foreign key constraint failed");
return SQLITE_ERROR;
}
return SQLITE_OK;
}
#endif
/*
** This routine is called the when a VDBE tries to halt. If the VDBE
** has made changes and is in autocommit mode, then commit those
** changes. If a rollback is needed, then do the rollback.
**
** This routine is the only way to move the state of a VM from
** SQLITE_MAGIC_RUN to SQLITE_MAGIC_HALT. It is harmless to
** call this on a VM that is in the SQLITE_MAGIC_HALT state.
**
** Return an error code. If the commit could not complete because of
** lock contention, return SQLITE_BUSY. If SQLITE_BUSY is returned, it
** means the close did not happen and needs to be repeated.
*/
int sqlite3VdbeHalt(Vdbe *p){
int rc; /* Used to store transient return codes */
sqlite3 *db = p->db;
/* This function contains the logic that determines if a statement or
** transaction will be committed or rolled back as a result of the
** execution of this virtual machine.
**
** If any of the following errors occur:
**
** SQLITE_NOMEM
** SQLITE_IOERR
** SQLITE_FULL
** SQLITE_INTERRUPT
**
** Then the internal cache might have been left in an inconsistent
** state. We need to rollback the statement transaction, if there is
** one, or the complete transaction if there is no statement transaction.
*/
if( p->db->mallocFailed ){
p->rc = SQLITE_NOMEM;
}
closeAllCursors(p);
if( p->magic!=VDBE_MAGIC_RUN ){
return SQLITE_OK;
}
checkActiveVdbeCnt(db);
/* No commit or rollback needed if the program never started */
if( p->pc>=0 ){
int mrc; /* Primary error code from p->rc */
int eStatementOp = 0;
int isSpecialError; /* Set to true if a 'special' error */
/* Lock all btrees used by the statement */
sqlite3VdbeEnter(p);
/* Check for one of the special errors */
mrc = p->rc & 0xff;
assert( p->rc!=SQLITE_IOERR_BLOCKED ); /* This error no longer exists */
isSpecialError = mrc==SQLITE_NOMEM || mrc==SQLITE_IOERR
|| mrc==SQLITE_INTERRUPT || mrc==SQLITE_FULL;
if( isSpecialError ){
/* If the query was read-only and the error code is SQLITE_INTERRUPT,
** no rollback is necessary. Otherwise, at least a savepoint
** transaction must be rolled back to restore the database to a
** consistent state.
**
** Even if the statement is read-only, it is important to perform
** a statement or transaction rollback operation. If the error
** occured while writing to the journal, sub-journal or database
** file as part of an effort to free up cache space (see function
** pagerStress() in pager.c), the rollback is required to restore
** the pager to a consistent state.
*/
if( !p->readOnly || mrc!=SQLITE_INTERRUPT ){
if( (mrc==SQLITE_NOMEM || mrc==SQLITE_FULL) && p->usesStmtJournal ){
eStatementOp = SAVEPOINT_ROLLBACK;
}else{
/* We are forced to roll back the active transaction. Before doing
** so, abort any other statements this handle currently has active.
*/
invalidateCursorsOnModifiedBtrees(db);
sqlite3RollbackAll(db);
sqlite3CloseSavepoints(db);
db->autoCommit = 1;
}
}
}
/* Check for immediate foreign key violations. */
if( p->rc==SQLITE_OK ){
sqlite3VdbeCheckFk(p, 0);
}
/* If the auto-commit flag is set and this is the only active writer
** VM, then we do either a commit or rollback of the current transaction.
**
** Note: This block also runs if one of the special errors handled
** above has occurred.
*/
if( !sqlite3VtabInSync(db)
&& db->autoCommit
&& db->writeVdbeCnt==(p->readOnly==0)
){
if( p->rc==SQLITE_OK || (p->errorAction==OE_Fail && !isSpecialError) ){
rc = sqlite3VdbeCheckFk(p, 1);
if( rc!=SQLITE_OK ){
if( NEVER(p->readOnly) ){
sqlite3VdbeLeave(p);
return SQLITE_ERROR;
}
rc = SQLITE_CONSTRAINT;
}else{
/* The auto-commit flag is true, the vdbe program was successful
** or hit an 'OR FAIL' constraint and there are no deferred foreign
** key constraints to hold up the transaction. This means a commit
** is required. */
rc = vdbeCommit(db, p);
}
if( rc==SQLITE_BUSY && p->readOnly ){
sqlite3VdbeLeave(p);
return SQLITE_BUSY;
}else if( rc!=SQLITE_OK ){
p->rc = rc;
sqlite3RollbackAll(db);
}else{
db->nDeferredCons = 0;
sqlite3CommitInternalChanges(db);
}
}else{
sqlite3RollbackAll(db);
}
db->nStatement = 0;
}else if( eStatementOp==0 ){
if( p->rc==SQLITE_OK || p->errorAction==OE_Fail ){
eStatementOp = SAVEPOINT_RELEASE;
}else if( p->errorAction==OE_Abort ){
eStatementOp = SAVEPOINT_ROLLBACK;
}else{
invalidateCursorsOnModifiedBtrees(db);
sqlite3RollbackAll(db);
sqlite3CloseSavepoints(db);
db->autoCommit = 1;
}
}
/* If eStatementOp is non-zero, then a statement transaction needs to
** be committed or rolled back. Call sqlite3VdbeCloseStatement() to
** do so. If this operation returns an error, and the current statement
** error code is SQLITE_OK or SQLITE_CONSTRAINT, then promote the
** current statement error code.
**
** Note that sqlite3VdbeCloseStatement() can only fail if eStatementOp
** is SAVEPOINT_ROLLBACK. But if p->rc==SQLITE_OK then eStatementOp
** must be SAVEPOINT_RELEASE. Hence the NEVER(p->rc==SQLITE_OK) in
** the following code.
*/
if( eStatementOp ){
rc = sqlite3VdbeCloseStatement(p, eStatementOp);
if( rc ){
assert( eStatementOp==SAVEPOINT_ROLLBACK );
if( NEVER(p->rc==SQLITE_OK) || p->rc==SQLITE_CONSTRAINT ){
p->rc = rc;
sqlite3DbFree(db, p->zErrMsg);
p->zErrMsg = 0;
}
invalidateCursorsOnModifiedBtrees(db);
sqlite3RollbackAll(db);
sqlite3CloseSavepoints(db);
db->autoCommit = 1;
}
}
/* If this was an INSERT, UPDATE or DELETE and no statement transaction
** has been rolled back, update the database connection change-counter.
*/
if( p->changeCntOn ){
if( eStatementOp!=SAVEPOINT_ROLLBACK ){
sqlite3VdbeSetChanges(db, p->nChange);
}else{
sqlite3VdbeSetChanges(db, 0);
}
p->nChange = 0;
}
/* Rollback or commit any schema changes that occurred. */
if( p->rc!=SQLITE_OK && db->flags&SQLITE_InternChanges ){
sqlite3ResetInternalSchema(db, -1);
db->flags = (db->flags | SQLITE_InternChanges);
}
/* Release the locks */
sqlite3VdbeLeave(p);
}
/* We have successfully halted and closed the VM. Record this fact. */
if( p->pc>=0 ){
db->activeVdbeCnt--;
if( !p->readOnly ){
db->writeVdbeCnt--;
}
assert( db->activeVdbeCnt>=db->writeVdbeCnt );
}
p->magic = VDBE_MAGIC_HALT;
checkActiveVdbeCnt(db);
if( p->db->mallocFailed ){
p->rc = SQLITE_NOMEM;
}
/* If the auto-commit flag is set to true, then any locks that were held
** by connection db have now been released. Call sqlite3ConnectionUnlocked()
** to invoke any required unlock-notify callbacks.
*/
if( db->autoCommit ){
sqlite3ConnectionUnlocked(db);
}
assert( db->activeVdbeCnt>0 || db->autoCommit==0 || db->nStatement==0 );
return (p->rc==SQLITE_BUSY ? SQLITE_BUSY : SQLITE_OK);
}
/*
** Each VDBE holds the result of the most recent sqlite3_step() call
** in p->rc. This routine sets that result back to SQLITE_OK.
*/
void sqlite3VdbeResetStepResult(Vdbe *p){
p->rc = SQLITE_OK;
}
/*
** Clean up a VDBE after execution but do not delete the VDBE just yet.
** Write any error messages into *pzErrMsg. Return the result code.
**
** After this routine is run, the VDBE should be ready to be executed
** again.
**
** To look at it another way, this routine resets the state of the
** virtual machine from VDBE_MAGIC_RUN or VDBE_MAGIC_HALT back to
** VDBE_MAGIC_INIT.
*/
int sqlite3VdbeReset(Vdbe *p){
sqlite3 *db;
db = p->db;
/* If the VM did not run to completion or if it encountered an
** error, then it might not have been halted properly. So halt
** it now.
*/
sqlite3VdbeHalt(p);
/* If the VDBE has be run even partially, then transfer the error code
** and error message from the VDBE into the main database structure. But
** if the VDBE has just been set to run but has not actually executed any
** instructions yet, leave the main database error information unchanged.
*/
if( p->pc>=0 ){
if( p->zErrMsg ){
sqlite3BeginBenignMalloc();
sqlite3ValueSetStr(db->pErr,-1,p->zErrMsg,SQLITE_UTF8,SQLITE_TRANSIENT);
sqlite3EndBenignMalloc();
db->errCode = p->rc;
sqlite3DbFree(db, p->zErrMsg);
p->zErrMsg = 0;
}else if( p->rc ){
sqlite3Error(db, p->rc, 0);
}else{
sqlite3Error(db, SQLITE_OK, 0);
}
if( p->runOnlyOnce ) p->expired = 1;
}else if( p->rc && p->expired ){
/* The expired flag was set on the VDBE before the first call
** to sqlite3_step(). For consistency (since sqlite3_step() was
** called), set the database error in this case as well.
*/
sqlite3Error(db, p->rc, 0);
sqlite3ValueSetStr(db->pErr, -1, p->zErrMsg, SQLITE_UTF8, SQLITE_TRANSIENT);
sqlite3DbFree(db, p->zErrMsg);
p->zErrMsg = 0;
}
/* Reclaim all memory used by the VDBE
*/
Cleanup(p);
/* Save profiling information from this VDBE run.
*/
#ifdef VDBE_PROFILE
{
FILE *out = fopen("vdbe_profile.out", "a");
if( out ){
int i;
fprintf(out, "---- ");
for(i=0; i<p->nOp; i++){
fprintf(out, "%02x", p->aOp[i].opcode);
}
fprintf(out, "\n");
for(i=0; i<p->nOp; i++){
fprintf(out, "%6d %10lld %8lld ",
p->aOp[i].cnt,
p->aOp[i].cycles,
p->aOp[i].cnt>0 ? p->aOp[i].cycles/p->aOp[i].cnt : 0
);
sqlite3VdbePrintOp(out, i, &p->aOp[i]);
}
fclose(out);
}
}
#endif
p->magic = VDBE_MAGIC_INIT;
return p->rc & db->errMask;
}
/*
** Clean up and delete a VDBE after execution. Return an integer which is
** the result code. Write any error message text into *pzErrMsg.
*/
int sqlite3VdbeFinalize(Vdbe *p){
int rc = SQLITE_OK;
if( p->magic==VDBE_MAGIC_RUN || p->magic==VDBE_MAGIC_HALT ){
rc = sqlite3VdbeReset(p);
assert( (rc & p->db->errMask)==rc );
}
sqlite3VdbeDelete(p);
return rc;
}
/*
** Call the destructor for each auxdata entry in pVdbeFunc for which
** the corresponding bit in mask is clear. Auxdata entries beyond 31
** are always destroyed. To destroy all auxdata entries, call this
** routine with mask==0.
*/
void sqlite3VdbeDeleteAuxData(VdbeFunc *pVdbeFunc, int mask){
int i;
for(i=0; i<pVdbeFunc->nAux; i++){
struct AuxData *pAux = &pVdbeFunc->apAux[i];
if( (i>31 || !(mask&(((u32)1)<<i))) && pAux->pAux ){
if( pAux->xDelete ){
pAux->xDelete(pAux->pAux);
}
pAux->pAux = 0;
}
}
}
/*
** Free all memory associated with the Vdbe passed as the second argument.
** The difference between this function and sqlite3VdbeDelete() is that
** VdbeDelete() also unlinks the Vdbe from the list of VMs associated with
** the database connection.
*/
void sqlite3VdbeDeleteObject(sqlite3 *db, Vdbe *p){
SubProgram *pSub, *pNext;
assert( p->db==0 || p->db==db );
releaseMemArray(p->aVar, p->nVar);
releaseMemArray(p->aColName, p->nResColumn*COLNAME_N);
for(pSub=p->pProgram; pSub; pSub=pNext){
pNext = pSub->pNext;
vdbeFreeOpArray(db, pSub->aOp, pSub->nOp);
sqlite3DbFree(db, pSub);
}
vdbeFreeOpArray(db, p->aOp, p->nOp);
sqlite3DbFree(db, p->aLabel);
sqlite3DbFree(db, p->aColName);
sqlite3DbFree(db, p->zSql);
sqlite3DbFree(db, p->pFree);
sqlite3DbFree(db, p);
}
/*
** Delete an entire VDBE.
*/
void sqlite3VdbeDelete(Vdbe *p){
sqlite3 *db;
if( NEVER(p==0) ) return;
db = p->db;
if( p->pPrev ){
p->pPrev->pNext = p->pNext;
}else{
assert( db->pVdbe==p );
db->pVdbe = p->pNext;
}
if( p->pNext ){
p->pNext->pPrev = p->pPrev;
}
p->magic = VDBE_MAGIC_DEAD;
p->db = 0;
sqlite3VdbeDeleteObject(db, p);
}
/*
** Make sure the cursor p is ready to read or write the row to which it
** was last positioned. Return an error code if an OOM fault or I/O error
** prevents us from positioning the cursor to its correct position.
**
** If a MoveTo operation is pending on the given cursor, then do that
** MoveTo now. If no move is pending, check to see if the row has been
** deleted out from under the cursor and if it has, mark the row as
** a NULL row.
**
** If the cursor is already pointing to the correct row and that row has
** not been deleted out from under the cursor, then this routine is a no-op.
*/
int sqlite3VdbeCursorMoveto(VdbeCursor *p){
if( p->deferredMoveto ){
int res, rc;
#ifdef SQLITE_TEST
extern int sqlite3_search_count;
#endif
assert( p->isTable );
rc = sqlite3BtreeMovetoUnpacked(p->pCursor, 0, p->movetoTarget, 0, &res);
if( rc ) return rc;
p->lastRowid = p->movetoTarget;
if( res!=0 ) return SQLITE_CORRUPT_BKPT;
p->rowidIsValid = 1;
#ifdef SQLITE_TEST
sqlite3_search_count++;
#endif
p->deferredMoveto = 0;
p->cacheStatus = CACHE_STALE;
}else if( ALWAYS(p->pCursor) ){
int hasMoved;
int rc = sqlite3BtreeCursorHasMoved(p->pCursor, &hasMoved);
if( rc ) return rc;
if( hasMoved ){
p->cacheStatus = CACHE_STALE;
p->nullRow = 1;
}
}
return SQLITE_OK;
}
/*
** The following functions:
**
** sqlite3VdbeSerialType()
** sqlite3VdbeSerialTypeLen()
** sqlite3VdbeSerialLen()
** sqlite3VdbeSerialPut()
** sqlite3VdbeSerialGet()
**
** encapsulate the code that serializes values for storage in SQLite
** data and index records. Each serialized value consists of a
** 'serial-type' and a blob of data. The serial type is an 8-byte unsigned
** integer, stored as a varint.
**
** In an SQLite index record, the serial type is stored directly before
** the blob of data that it corresponds to. In a table record, all serial
** types are stored at the start of the record, and the blobs of data at
** the end. Hence these functions allow the caller to handle the
** serial-type and data blob seperately.
**
** The following table describes the various storage classes for data:
**
** serial type bytes of data type
** -------------- --------------- ---------------
** 0 0 NULL
** 1 1 signed integer
** 2 2 signed integer
** 3 3 signed integer
** 4 4 signed integer
** 5 6 signed integer
** 6 8 signed integer
** 7 8 IEEE float
** 8 0 Integer constant 0
** 9 0 Integer constant 1
** 10,11 reserved for expansion
** N>=12 and even (N-12)/2 BLOB
** N>=13 and odd (N-13)/2 text
**
** The 8 and 9 types were added in 3.3.0, file format 4. Prior versions
** of SQLite will not understand those serial types.
*/
/*
** Return the serial-type for the value stored in pMem.
*/
u32 sqlite3VdbeSerialType(Mem *pMem, int file_format){
int flags = pMem->flags;
int n;
if( flags&MEM_Null ){
return 0;
}
if( flags&MEM_Int ){
/* Figure out whether to use 1, 2, 4, 6 or 8 bytes. */
# define MAX_6BYTE ((((i64)0x00008000)<<32)-1)
i64 i = pMem->u.i;
u64 u;
if( file_format>=4 && (i&1)==i ){
return 8+(u32)i;
}
if( i<0 ){
if( i<(-MAX_6BYTE) ) return 6;
/* Previous test prevents: u = -(-9223372036854775808) */
u = -i;
}else{
u = i;
}
if( u<=127 ) return 1;
if( u<=32767 ) return 2;
if( u<=8388607 ) return 3;
if( u<=2147483647 ) return 4;
if( u<=MAX_6BYTE ) return 5;
return 6;
}
if( flags&MEM_Real ){
return 7;
}
assert( pMem->db->mallocFailed || flags&(MEM_Str|MEM_Blob) );
n = pMem->n;
if( flags & MEM_Zero ){
n += pMem->u.nZero;
}
assert( n>=0 );
return ((n*2) + 12 + ((flags&MEM_Str)!=0));
}
/*
** Return the length of the data corresponding to the supplied serial-type.
*/
u32 sqlite3VdbeSerialTypeLen(u32 serial_type){
if( serial_type>=12 ){
return (serial_type-12)/2;
}else{
static const u8 aSize[] = { 0, 1, 2, 3, 4, 6, 8, 8, 0, 0, 0, 0 };
return aSize[serial_type];
}
}
/*
** If we are on an architecture with mixed-endian floating
** points (ex: ARM7) then swap the lower 4 bytes with the
** upper 4 bytes. Return the result.
**
** For most architectures, this is a no-op.
**
** (later): It is reported to me that the mixed-endian problem
** on ARM7 is an issue with GCC, not with the ARM7 chip. It seems
** that early versions of GCC stored the two words of a 64-bit
** float in the wrong order. And that error has been propagated
** ever since. The blame is not necessarily with GCC, though.
** GCC might have just copying the problem from a prior compiler.
** I am also told that newer versions of GCC that follow a different
** ABI get the byte order right.
**
** Developers using SQLite on an ARM7 should compile and run their
** application using -DSQLITE_DEBUG=1 at least once. With DEBUG
** enabled, some asserts below will ensure that the byte order of
** floating point values is correct.
**
** (2007-08-30) Frank van Vugt has studied this problem closely
** and has send his findings to the SQLite developers. Frank
** writes that some Linux kernels offer floating point hardware
** emulation that uses only 32-bit mantissas instead of a full
** 48-bits as required by the IEEE standard. (This is the
** CONFIG_FPE_FASTFPE option.) On such systems, floating point
** byte swapping becomes very complicated. To avoid problems,
** the necessary byte swapping is carried out using a 64-bit integer
** rather than a 64-bit float. Frank assures us that the code here
** works for him. We, the developers, have no way to independently
** verify this, but Frank seems to know what he is talking about
** so we trust him.
*/
#ifdef SQLITE_MIXED_ENDIAN_64BIT_FLOAT
static u64 floatSwap(u64 in){
union {
u64 r;
u32 i[2];
} u;
u32 t;
u.r = in;
t = u.i[0];
u.i[0] = u.i[1];
u.i[1] = t;
return u.r;
}
# define swapMixedEndianFloat(X) X = floatSwap(X)
#else
# define swapMixedEndianFloat(X)
#endif
/*
** Write the serialized data blob for the value stored in pMem into
** buf. It is assumed that the caller has allocated sufficient space.
** Return the number of bytes written.
**
** nBuf is the amount of space left in buf[]. nBuf must always be
** large enough to hold the entire field. Except, if the field is
** a blob with a zero-filled tail, then buf[] might be just the right
** size to hold everything except for the zero-filled tail. If buf[]
** is only big enough to hold the non-zero prefix, then only write that
** prefix into buf[]. But if buf[] is large enough to hold both the
** prefix and the tail then write the prefix and set the tail to all
** zeros.
**
** Return the number of bytes actually written into buf[]. The number
** of bytes in the zero-filled tail is included in the return value only
** if those bytes were zeroed in buf[].
*/
u32 sqlite3VdbeSerialPut(u8 *buf, int nBuf, Mem *pMem, int file_format){
u32 serial_type = sqlite3VdbeSerialType(pMem, file_format);
u32 len;
/* Integer and Real */
if( serial_type<=7 && serial_type>0 ){
u64 v;
u32 i;
if( serial_type==7 ){
assert( sizeof(v)==sizeof(pMem->r) );
memcpy(&v, &pMem->r, sizeof(v));
swapMixedEndianFloat(v);
}else{
v = pMem->u.i;
}
len = i = sqlite3VdbeSerialTypeLen(serial_type);
assert( len<=(u32)nBuf );
while( i-- ){
buf[i] = (u8)(v&0xFF);
v >>= 8;
}
return len;
}
/* String or blob */
if( serial_type>=12 ){
assert( pMem->n + ((pMem->flags & MEM_Zero)?pMem->u.nZero:0)
== (int)sqlite3VdbeSerialTypeLen(serial_type) );
assert( pMem->n<=nBuf );
len = pMem->n;
memcpy(buf, pMem->z, len);
if( pMem->flags & MEM_Zero ){
len += pMem->u.nZero;
assert( nBuf>=0 );
if( len > (u32)nBuf ){
len = (u32)nBuf;
}
memset(&buf[pMem->n], 0, len-pMem->n);
}
return len;
}
/* NULL or constants 0 or 1 */
return 0;
}
/*
** Deserialize the data blob pointed to by buf as serial type serial_type
** and store the result in pMem. Return the number of bytes read.
*/
u32 sqlite3VdbeSerialGet(
const unsigned char *buf, /* Buffer to deserialize from */
u32 serial_type, /* Serial type to deserialize */
Mem *pMem /* Memory cell to write value into */
){
switch( serial_type ){
case 10: /* Reserved for future use */
case 11: /* Reserved for future use */
case 0: { /* NULL */
pMem->flags = MEM_Null;
break;
}
case 1: { /* 1-byte signed integer */
pMem->u.i = (signed char)buf[0];
pMem->flags = MEM_Int;
return 1;
}
case 2: { /* 2-byte signed integer */
pMem->u.i = (((signed char)buf[0])<<8) | buf[1];
pMem->flags = MEM_Int;
return 2;
}
case 3: { /* 3-byte signed integer */
pMem->u.i = (((signed char)buf[0])<<16) | (buf[1]<<8) | buf[2];
pMem->flags = MEM_Int;
return 3;
}
case 4: { /* 4-byte signed integer */
pMem->u.i = (buf[0]<<24) | (buf[1]<<16) | (buf[2]<<8) | buf[3];
pMem->flags = MEM_Int;
return 4;
}
case 5: { /* 6-byte signed integer */
u64 x = (((signed char)buf[0])<<8) | buf[1];
u32 y = (buf[2]<<24) | (buf[3]<<16) | (buf[4]<<8) | buf[5];
x = (x<<32) | y;
pMem->u.i = *(i64*)&x;
pMem->flags = MEM_Int;
return 6;
}
case 6: /* 8-byte signed integer */
case 7: { /* IEEE floating point */
u64 x;
u32 y;
#if !defined(NDEBUG) && !defined(SQLITE_OMIT_FLOATING_POINT)
/* Verify that integers and floating point values use the same
** byte order. Or, that if SQLITE_MIXED_ENDIAN_64BIT_FLOAT is
** defined that 64-bit floating point values really are mixed
** endian.
*/
static const u64 t1 = ((u64)0x3ff00000)<<32;
static const double r1 = 1.0;
u64 t2 = t1;
swapMixedEndianFloat(t2);
assert( sizeof(r1)==sizeof(t2) && memcmp(&r1, &t2, sizeof(r1))==0 );
#endif
x = (buf[0]<<24) | (buf[1]<<16) | (buf[2]<<8) | buf[3];
y = (buf[4]<<24) | (buf[5]<<16) | (buf[6]<<8) | buf[7];
x = (x<<32) | y;
if( serial_type==6 ){
pMem->u.i = *(i64*)&x;
pMem->flags = MEM_Int;
}else{
assert( sizeof(x)==8 && sizeof(pMem->r)==8 );
swapMixedEndianFloat(x);
memcpy(&pMem->r, &x, sizeof(x));
pMem->flags = sqlite3IsNaN(pMem->r) ? MEM_Null : MEM_Real;
}
return 8;
}
case 8: /* Integer 0 */
case 9: { /* Integer 1 */
pMem->u.i = serial_type-8;
pMem->flags = MEM_Int;
return 0;
}
default: {
u32 len = (serial_type-12)/2;
pMem->z = (char *)buf;
pMem->n = len;
pMem->xDel = 0;
if( serial_type&0x01 ){
pMem->flags = MEM_Str | MEM_Ephem;
}else{
pMem->flags = MEM_Blob | MEM_Ephem;
}
return len;
}
}
return 0;
}
/*
** Given the nKey-byte encoding of a record in pKey[], parse the
** record into a UnpackedRecord structure. Return a pointer to
** that structure.
**
** The calling function might provide szSpace bytes of memory
** space at pSpace. This space can be used to hold the returned
** VDbeParsedRecord structure if it is large enough. If it is
** not big enough, space is obtained from sqlite3_malloc().
**
** The returned structure should be closed by a call to
** sqlite3VdbeDeleteUnpackedRecord().
*/
UnpackedRecord *sqlite3VdbeRecordUnpack(
KeyInfo *pKeyInfo, /* Information about the record format */
int nKey, /* Size of the binary record */
const void *pKey, /* The binary record */
char *pSpace, /* Unaligned space available to hold the object */
int szSpace /* Size of pSpace[] in bytes */
){
const unsigned char *aKey = (const unsigned char *)pKey;
UnpackedRecord *p; /* The unpacked record that we will return */
int nByte; /* Memory space needed to hold p, in bytes */
int d;
u32 idx;
u16 u; /* Unsigned loop counter */
u32 szHdr;
Mem *pMem;
int nOff; /* Increase pSpace by this much to 8-byte align it */
/*
** We want to shift the pointer pSpace up such that it is 8-byte aligned.
** Thus, we need to calculate a value, nOff, between 0 and 7, to shift
** it by. If pSpace is already 8-byte aligned, nOff should be zero.
*/
nOff = (8 - (SQLITE_PTR_TO_INT(pSpace) & 7)) & 7;
pSpace += nOff;
szSpace -= nOff;
nByte = ROUND8(sizeof(UnpackedRecord)) + sizeof(Mem)*(pKeyInfo->nField+1);
if( nByte>szSpace ){
p = sqlite3DbMallocRaw(pKeyInfo->db, nByte);
if( p==0 ) return 0;
p->flags = UNPACKED_NEED_FREE | UNPACKED_NEED_DESTROY;
}else{
p = (UnpackedRecord*)pSpace;
p->flags = UNPACKED_NEED_DESTROY;
}
p->pKeyInfo = pKeyInfo;
p->nField = pKeyInfo->nField + 1;
p->aMem = pMem = (Mem*)&((char*)p)[ROUND8(sizeof(UnpackedRecord))];
assert( EIGHT_BYTE_ALIGNMENT(pMem) );
idx = getVarint32(aKey, szHdr);
d = szHdr;
u = 0;
while( idx<szHdr && u<p->nField && d<=nKey ){
u32 serial_type;
idx += getVarint32(&aKey[idx], serial_type);
pMem->enc = pKeyInfo->enc;
pMem->db = pKeyInfo->db;
pMem->flags = 0;
pMem->zMalloc = 0;
d += sqlite3VdbeSerialGet(&aKey[d], serial_type, pMem);
pMem++;
u++;
}
assert( u<=pKeyInfo->nField + 1 );
p->nField = u;
return (void*)p;
}
/*
** This routine destroys a UnpackedRecord object.
*/
void sqlite3VdbeDeleteUnpackedRecord(UnpackedRecord *p){
int i;
Mem *pMem;
assert( p!=0 );
assert( p->flags & UNPACKED_NEED_DESTROY );
for(i=0, pMem=p->aMem; i<p->nField; i++, pMem++){
/* The unpacked record is always constructed by the
** sqlite3VdbeUnpackRecord() function above, which makes all
** strings and blobs static. And none of the elements are
** ever transformed, so there is never anything to delete.
*/
if( NEVER(pMem->zMalloc) ) sqlite3VdbeMemRelease(pMem);
}
if( p->flags & UNPACKED_NEED_FREE ){
sqlite3DbFree(p->pKeyInfo->db, p);
}
}
/*
** This function compares the two table rows or index records
** specified by {nKey1, pKey1} and pPKey2. It returns a negative, zero
** or positive integer if key1 is less than, equal to or
** greater than key2. The {nKey1, pKey1} key must be a blob
** created by th OP_MakeRecord opcode of the VDBE. The pPKey2
** key must be a parsed key such as obtained from
** sqlite3VdbeParseRecord.
**
** Key1 and Key2 do not have to contain the same number of fields.
** The key with fewer fields is usually compares less than the
** longer key. However if the UNPACKED_INCRKEY flags in pPKey2 is set
** and the common prefixes are equal, then key1 is less than key2.
** Or if the UNPACKED_MATCH_PREFIX flag is set and the prefixes are
** equal, then the keys are considered to be equal and
** the parts beyond the common prefix are ignored.
**
** If the UNPACKED_IGNORE_ROWID flag is set, then the last byte of
** the header of pKey1 is ignored. It is assumed that pKey1 is
** an index key, and thus ends with a rowid value. The last byte
** of the header will therefore be the serial type of the rowid:
** one of 1, 2, 3, 4, 5, 6, 8, or 9 - the integer serial types.
** The serial type of the final rowid will always be a single byte.
** By ignoring this last byte of the header, we force the comparison
** to ignore the rowid at the end of key1.
*/
int sqlite3VdbeRecordCompare(
int nKey1, const void *pKey1, /* Left key */
UnpackedRecord *pPKey2 /* Right key */
){
int d1; /* Offset into aKey[] of next data element */
u32 idx1; /* Offset into aKey[] of next header element */
u32 szHdr1; /* Number of bytes in header */
int i = 0;
int nField;
int rc = 0;
const unsigned char *aKey1 = (const unsigned char *)pKey1;
KeyInfo *pKeyInfo;
Mem mem1;
pKeyInfo = pPKey2->pKeyInfo;
mem1.enc = pKeyInfo->enc;
mem1.db = pKeyInfo->db;
/* mem1.flags = 0; // Will be initialized by sqlite3VdbeSerialGet() */
VVA_ONLY( mem1.zMalloc = 0; ) /* Only needed by assert() statements */
/* Compilers may complain that mem1.u.i is potentially uninitialized.
** We could initialize it, as shown here, to silence those complaints.
** But in fact, mem1.u.i will never actually be used initialized, and doing
** the unnecessary initialization has a measurable negative performance
** impact, since this routine is a very high runner. And so, we choose
** to ignore the compiler warnings and leave this variable uninitialized.
*/
/* mem1.u.i = 0; // not needed, here to silence compiler warning */
idx1 = getVarint32(aKey1, szHdr1);
d1 = szHdr1;
if( pPKey2->flags & UNPACKED_IGNORE_ROWID ){
szHdr1--;
}
nField = pKeyInfo->nField;
while( idx1<szHdr1 && i<pPKey2->nField ){
u32 serial_type1;
/* Read the serial types for the next element in each key. */
idx1 += getVarint32( aKey1+idx1, serial_type1 );
if( d1>=nKey1 && sqlite3VdbeSerialTypeLen(serial_type1)>0 ) break;
/* Extract the values to be compared.
*/
d1 += sqlite3VdbeSerialGet(&aKey1[d1], serial_type1, &mem1);
/* Do the comparison
*/
rc = sqlite3MemCompare(&mem1, &pPKey2->aMem[i],
i<nField ? pKeyInfo->aColl[i] : 0);
if( rc!=0 ){
assert( mem1.zMalloc==0 ); /* See comment below */
/* Invert the result if we are using DESC sort order. */
if( pKeyInfo->aSortOrder && i<nField && pKeyInfo->aSortOrder[i] ){
rc = -rc;
}
/* If the PREFIX_SEARCH flag is set and all fields except the final
** rowid field were equal, then clear the PREFIX_SEARCH flag and set
** pPKey2->rowid to the value of the rowid field in (pKey1, nKey1).
** This is used by the OP_IsUnique opcode.
*/
if( (pPKey2->flags & UNPACKED_PREFIX_SEARCH) && i==(pPKey2->nField-1) ){
assert( idx1==szHdr1 && rc );
assert( mem1.flags & MEM_Int );
pPKey2->flags &= ~UNPACKED_PREFIX_SEARCH;
pPKey2->rowid = mem1.u.i;
}
return rc;
}
i++;
}
/* No memory allocation is ever used on mem1. Prove this using
** the following assert(). If the assert() fails, it indicates a
** memory leak and a need to call sqlite3VdbeMemRelease(&mem1).
*/
assert( mem1.zMalloc==0 );
/* rc==0 here means that one of the keys ran out of fields and
** all the fields up to that point were equal. If the UNPACKED_INCRKEY
** flag is set, then break the tie by treating key2 as larger.
** If the UPACKED_PREFIX_MATCH flag is set, then keys with common prefixes
** are considered to be equal. Otherwise, the longer key is the
** larger. As it happens, the pPKey2 will always be the longer
** if there is a difference.
*/
assert( rc==0 );
if( pPKey2->flags & UNPACKED_INCRKEY ){
rc = -1;
}else if( pPKey2->flags & UNPACKED_PREFIX_MATCH ){
/* Leave rc==0 */
}else if( idx1<szHdr1 ){
rc = 1;
}
return rc;
}
/*
** pCur points at an index entry created using the OP_MakeRecord opcode.
** Read the rowid (the last field in the record) and store it in *rowid.
** Return SQLITE_OK if everything works, or an error code otherwise.
**
** pCur might be pointing to text obtained from a corrupt database file.
** So the content cannot be trusted. Do appropriate checks on the content.
*/
int sqlite3VdbeIdxRowid(sqlite3 *db, BtCursor *pCur, i64 *rowid){
i64 nCellKey = 0;
int rc;
u32 szHdr; /* Size of the header */
u32 typeRowid; /* Serial type of the rowid */
u32 lenRowid; /* Size of the rowid */
Mem m, v;
UNUSED_PARAMETER(db);
/* Get the size of the index entry. Only indices entries of less
** than 2GiB are support - anything large must be database corruption.
** Any corruption is detected in sqlite3BtreeParseCellPtr(), though, so
** this code can safely assume that nCellKey is 32-bits
*/
assert( sqlite3BtreeCursorIsValid(pCur) );
rc = sqlite3BtreeKeySize(pCur, &nCellKey);
assert( rc==SQLITE_OK ); /* pCur is always valid so KeySize cannot fail */
assert( (nCellKey & SQLITE_MAX_U32)==(u64)nCellKey );
/* Read in the complete content of the index entry */
memset(&m, 0, sizeof(m));
rc = sqlite3VdbeMemFromBtree(pCur, 0, (int)nCellKey, 1, &m);
if( rc ){
return rc;
}
/* The index entry must begin with a header size */
(void)getVarint32((u8*)m.z, szHdr);
testcase( szHdr==3 );
testcase( szHdr==m.n );
if( unlikely(szHdr<3 || (int)szHdr>m.n) ){
goto idx_rowid_corruption;
}
/* The last field of the index should be an integer - the ROWID.
** Verify that the last entry really is an integer. */
(void)getVarint32((u8*)&m.z[szHdr-1], typeRowid);
testcase( typeRowid==1 );
testcase( typeRowid==2 );
testcase( typeRowid==3 );
testcase( typeRowid==4 );
testcase( typeRowid==5 );
testcase( typeRowid==6 );
testcase( typeRowid==8 );
testcase( typeRowid==9 );
if( unlikely(typeRowid<1 || typeRowid>9 || typeRowid==7) ){
goto idx_rowid_corruption;
}
lenRowid = sqlite3VdbeSerialTypeLen(typeRowid);
testcase( (u32)m.n==szHdr+lenRowid );
if( unlikely((u32)m.n<szHdr+lenRowid) ){
goto idx_rowid_corruption;
}
/* Fetch the integer off the end of the index record */
sqlite3VdbeSerialGet((u8*)&m.z[m.n-lenRowid], typeRowid, &v);
*rowid = v.u.i;
sqlite3VdbeMemRelease(&m);
return SQLITE_OK;
/* Jump here if database corruption is detected after m has been
** allocated. Free the m object and return SQLITE_CORRUPT. */
idx_rowid_corruption:
testcase( m.zMalloc!=0 );
sqlite3VdbeMemRelease(&m);
return SQLITE_CORRUPT_BKPT;
}
/*
** Compare the key of the index entry that cursor pC is pointing to against
** the key string in pUnpacked. Write into *pRes a number
** that is negative, zero, or positive if pC is less than, equal to,
** or greater than pUnpacked. Return SQLITE_OK on success.
**
** pUnpacked is either created without a rowid or is truncated so that it
** omits the rowid at the end. The rowid at the end of the index entry
** is ignored as well. Hence, this routine only compares the prefixes
** of the keys prior to the final rowid, not the entire key.
*/
int sqlite3VdbeIdxKeyCompare(
VdbeCursor *pC, /* The cursor to compare against */
UnpackedRecord *pUnpacked, /* Unpacked version of key to compare against */
int *res /* Write the comparison result here */
){
i64 nCellKey = 0;
int rc;
BtCursor *pCur = pC->pCursor;
Mem m;
assert( sqlite3BtreeCursorIsValid(pCur) );
rc = sqlite3BtreeKeySize(pCur, &nCellKey);
assert( rc==SQLITE_OK ); /* pCur is always valid so KeySize cannot fail */
/* nCellKey will always be between 0 and 0xffffffff because of the say
** that btreeParseCellPtr() and sqlite3GetVarint32() are implemented */
if( nCellKey<=0 || nCellKey>0x7fffffff ){
*res = 0;
return SQLITE_CORRUPT_BKPT;
}
memset(&m, 0, sizeof(m));
rc = sqlite3VdbeMemFromBtree(pC->pCursor, 0, (int)nCellKey, 1, &m);
if( rc ){
return rc;
}
assert( pUnpacked->flags & UNPACKED_IGNORE_ROWID );
*res = sqlite3VdbeRecordCompare(m.n, m.z, pUnpacked);
sqlite3VdbeMemRelease(&m);
return SQLITE_OK;
}
/*
** This routine sets the value to be returned by subsequent calls to
** sqlite3_changes() on the database handle 'db'.
*/
void sqlite3VdbeSetChanges(sqlite3 *db, int nChange){
assert( sqlite3_mutex_held(db->mutex) );
db->nChange = nChange;
db->nTotalChange += nChange;
}
/*
** Set a flag in the vdbe to update the change counter when it is finalised
** or reset.
*/
void sqlite3VdbeCountChanges(Vdbe *v){
v->changeCntOn = 1;
}
/*
** Mark every prepared statement associated with a database connection
** as expired.
**
** An expired statement means that recompilation of the statement is
** recommend. Statements expire when things happen that make their
** programs obsolete. Removing user-defined functions or collating
** sequences, or changing an authorization function are the types of
** things that make prepared statements obsolete.
*/
void sqlite3ExpirePreparedStatements(sqlite3 *db){
Vdbe *p;
for(p = db->pVdbe; p; p=p->pNext){
p->expired = 1;
}
}
/*
** Return the database associated with the Vdbe.
*/
sqlite3 *sqlite3VdbeDb(Vdbe *v){
return v->db;
}
/*
** Return a pointer to an sqlite3_value structure containing the value bound
** parameter iVar of VM v. Except, if the value is an SQL NULL, return
** 0 instead. Unless it is NULL, apply affinity aff (one of the SQLITE_AFF_*
** constants) to the value before returning it.
**
** The returned value must be freed by the caller using sqlite3ValueFree().
*/
sqlite3_value *sqlite3VdbeGetValue(Vdbe *v, int iVar, u8 aff){
assert( iVar>0 );
if( v ){
Mem *pMem = &v->aVar[iVar-1];
if( 0==(pMem->flags & MEM_Null) ){
sqlite3_value *pRet = sqlite3ValueNew(v->db);
if( pRet ){
sqlite3VdbeMemCopy((Mem *)pRet, pMem);
sqlite3ValueApplyAffinity(pRet, aff, SQLITE_UTF8);
sqlite3VdbeMemStoreType((Mem *)pRet);
}
return pRet;
}
}
return 0;
}
/*
** Configure SQL variable iVar so that binding a new value to it signals
** to sqlite3_reoptimize() that re-preparing the statement may result
** in a better query plan.
*/
void sqlite3VdbeSetVarmask(Vdbe *v, int iVar){
assert( iVar>0 );
if( iVar>32 ){
v->expmask = 0xffffffff;
}else{
v->expmask |= ((u32)1 << (iVar-1));
}
}