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Diffstat (limited to 'src/vdbeaux.c')
-rw-r--r-- | src/vdbeaux.c | 3254 |
1 files changed, 3254 insertions, 0 deletions
diff --git a/src/vdbeaux.c b/src/vdbeaux.c new file mode 100644 index 0000000..75250238 --- /dev/null +++ b/src/vdbeaux.c @@ -0,0 +1,3254 @@ +/* +** 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; +#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 OP_ParseSchema opcode. This routine is broken out from +** sqlite3VdbeAddOp4() since it needs to also local all btrees. +** +** The zWhere string must have been obtained from sqlite3_malloc(). +** This routine will take ownership of the allocated memory. +*/ +void sqlite3VdbeAddParseSchemaOp(Vdbe *p, int iDb, char *zWhere){ + int j; + int addr = sqlite3VdbeAddOp3(p, OP_ParseSchema, iDb, 0, 0); + sqlite3VdbeChangeP4(p, addr, zWhere, P4_DYNAMIC); + for(j=0; j<p->db->nDb; j++) sqlite3VdbeUsesBtree(p, j); +} + +/* +** 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 + }else if( opcode==OP_Next || opcode==OP_SorterNext ){ + pOp->p4.xAdvance = sqlite3BtreeNext; + pOp->p4type = P4_ADVANCE; + }else if( opcode==OP_Prev ){ + pOp->p4.xAdvance = sqlite3BtreePrevious; + pOp->p4type = P4_ADVANCE; + } + + 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, u32 addr, int val){ + assert( p!=0 ); + if( ((u32)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, u32 addr, int val){ + assert( p!=0 ); + if( ((u32)p->nOp)>addr ){ + p->aOp[addr].p2 = val; + } +} + +/* +** Change the value of the P3 operand for a specific instruction. +*/ +void sqlite3VdbeChangeP3(Vdbe *p, u32 addr, int val){ + assert( p!=0 ); + if( ((u32)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 || p->db->mallocFailed ); + if( 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 the opcode at addr into OP_Noop +*/ +void sqlite3VdbeChangeToNoop(Vdbe *p, int addr){ + if( p->aOp ){ + VdbeOp *pOp = &p->aOp[addr]; + sqlite3 *db = p->db; + freeP4(db, pOp->p4type, pOp->p4.p); + memset(pOp, 0, sizeof(pOp[0])); + pOp->opcode = OP_Noop; + } +} + +/* +** 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. +*/ +static void vdbeVComment(Vdbe *p, const char *zFormat, va_list ap){ + assert( p->nOp>0 || p->aOp==0 ); + assert( p->aOp==0 || p->aOp[p->nOp-1].zComment==0 || p->db->mallocFailed ); + if( p->nOp ){ + assert( p->aOp ); + sqlite3DbFree(p->db, p->aOp[p->nOp-1].zComment); + p->aOp[p->nOp-1].zComment = sqlite3VMPrintf(p->db, zFormat, ap); + } +} +void sqlite3VdbeComment(Vdbe *p, const char *zFormat, ...){ + va_list ap; + if( p ){ + va_start(ap, zFormat); + vdbeVComment(p, zFormat, ap); + va_end(ap); + } +} +void sqlite3VdbeNoopComment(Vdbe *p, const char *zFormat, ...){ + va_list ap; + if( p ){ + sqlite3VdbeAddOp0(p, OP_Noop); + va_start(ap, zFormat); + vdbeVComment(p, 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 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; + } + case P4_ADVANCE: { + zTemp[0] = 0; + 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->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); + p->pResultSet = 0; + + 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->pResultSet = &p->aMem[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; +} + +/* +** Rewind the VDBE back to the beginning in preparation for +** running it. +*/ +void sqlite3VdbeRewind(Vdbe *p){ +#if defined(SQLITE_DEBUG) || defined(VDBE_PROFILE) + int i; +#endif + 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; + +#ifdef SQLITE_DEBUG + for(i=1; i<p->nMem; i++){ + assert( p->aMem[i].db==p->db ); + } +#endif + p->pc = -1; + p->rc = SQLITE_OK; + p->errorAction = OE_Abort; + p->magic = VDBE_MAGIC_RUN; + p->nChange = 0; + p->cacheCtr = 1; + p->minWriteFileFormat = 255; + p->iStatement = 0; + p->nFkConstraint = 0; +#ifdef VDBE_PROFILE + for(i=0; i<p->nOp; i++){ + p->aOp[i].cnt = 0; + p->aOp[i].cycles = 0; + } +#endif +} + +/* +** Prepare a virtual machine for execution for the first time after +** creating the virtual machine. 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 function may be called exact once on a each virtual machine. +** After this routine is called the VM has been "packaged" and is ready +** to run. After this routine is called, futher calls to +** sqlite3VdbeAddOp() functions are prohibited. This routine disconnects +** the Vdbe from the Parse object that helped generate it so that the +** the Vdbe becomes an independent entity and the Parse object can be +** destroyed. +** +** Use the sqlite3VdbeRewind() procedure to restore a virtual machine back +** to its initial state after it has been run. +*/ +void sqlite3VdbeMakeReady( + Vdbe *p, /* The VDBE */ + Parse *pParse /* Parsing context */ +){ + sqlite3 *db; /* The database connection */ + int nVar; /* Number of parameters */ + int nMem; /* Number of VM memory registers */ + int nCursor; /* Number of cursors required */ + int nArg; /* Number of arguments in subprograms */ + int n; /* Loop counter */ + u8 *zCsr; /* Memory available for allocation */ + u8 *zEnd; /* First byte past allocated memory */ + int nByte; /* How much extra memory is needed */ + + assert( p!=0 ); + assert( p->nOp>0 ); + assert( pParse!=0 ); + assert( p->magic==VDBE_MAGIC_INIT ); + db = p->db; + assert( db->mallocFailed==0 ); + nVar = pParse->nVar; + nMem = pParse->nMem; + nCursor = pParse->nTab; + nArg = pParse->nMaxArg; + + /* 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. + */ + zCsr = (u8*)&p->aOp[p->nOp]; /* Memory avaliable for allocation */ + zEnd = (u8*)&p->aOp[p->nOpAlloc]; /* First byte past end of zCsr[] */ + + resolveP2Values(p, &nArg); + p->usesStmtJournal = (u8)(pParse->isMultiWrite && pParse->mayAbort); + if( pParse->explain && nMem<10 ){ + nMem = 10; + } + memset(zCsr, 0, zEnd-zCsr); + zCsr += (zCsr - (u8*)0)&7; + assert( EIGHT_BYTE_ALIGNMENT(zCsr) ); + p->expired = 0; + + /* 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->azVar ){ + p->nzVar = pParse->nzVar; + memcpy(p->azVar, pParse->azVar, p->nzVar*sizeof(p->azVar[0])); + memset(pParse->azVar, 0, pParse->nzVar*sizeof(pParse->azVar[0])); + } + 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; + } + } + p->explain = pParse->explain; + sqlite3VdbeRewind(p); +} + +/* +** Close a VDBE cursor and release all the resources that cursor +** happens to hold. +*/ +void sqlite3VdbeFreeCursor(Vdbe *p, VdbeCursor *pCx){ + if( pCx==0 ){ + return; + } + sqlite3VdbeSorterClose(p->db, pCx); + 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; + } + sqlite3FileSuffix3(zMainFile, zMaster); + 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( rc==SQLITE_OK ){ + if( eOp==SAVEPOINT_ROLLBACK ){ + rc = sqlite3VtabSavepoint(db, SAVEPOINT_ROLLBACK, iSavepoint); + } + if( rc==SQLITE_OK ){ + rc = sqlite3VtabSavepoint(db, SAVEPOINT_RELEASE, iSavepoint); + } + } + + /* 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. + */ + if( eStatementOp ){ + rc = sqlite3VdbeCloseStatement(p, eStatementOp); + if( rc ){ + if( 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; +} + +/* +** Copy the error code and error message belonging to the VDBE passed +** as the first argument to its database handle (so that they will be +** returned by calls to sqlite3_errcode() and sqlite3_errmsg()). +** +** This function does not clear the VDBE error code or message, just +** copies them to the database handle. +*/ +int sqlite3VdbeTransferError(Vdbe *p){ + sqlite3 *db = p->db; + int rc = p->rc; + if( p->zErrMsg ){ + u8 mallocFailed = db->mallocFailed; + sqlite3BeginBenignMalloc(); + sqlite3ValueSetStr(db->pErr, -1, p->zErrMsg, SQLITE_UTF8, SQLITE_TRANSIENT); + sqlite3EndBenignMalloc(); + db->mallocFailed = mallocFailed; + db->errCode = rc; + }else{ + sqlite3Error(db, rc, 0); + } + return rc; +} + +/* +** 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 ){ + sqlite3VdbeTransferError(p); + sqlite3DbFree(db, p->zErrMsg); + p->zErrMsg = 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; + int i; + 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); + } + for(i=p->nzVar-1; i>=0; i--) sqlite3DbFree(db, p->azVar[i]); + 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; +} + +/* +** This routine is used to allocate sufficient space for an UnpackedRecord +** structure large enough to be used with sqlite3VdbeRecordUnpack() if +** the first argument is a pointer to KeyInfo structure pKeyInfo. +** +** The space is either allocated using sqlite3DbMallocRaw() or from within +** the unaligned buffer passed via the second and third arguments (presumably +** stack space). If the former, then *ppFree is set to a pointer that should +** be eventually freed by the caller using sqlite3DbFree(). Or, if the +** allocation comes from the pSpace/szSpace buffer, *ppFree is set to NULL +** before returning. +** +** If an OOM error occurs, NULL is returned. +*/ +UnpackedRecord *sqlite3VdbeAllocUnpackedRecord( + KeyInfo *pKeyInfo, /* Description of the record */ + char *pSpace, /* Unaligned space available */ + int szSpace, /* Size of pSpace[] in bytes */ + char **ppFree /* OUT: Caller should free this pointer */ +){ + UnpackedRecord *p; /* Unpacked record to return */ + int nOff; /* Increment pSpace by nOff to align it */ + int nByte; /* Number of bytes required for *p */ + + /* 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; + nByte = ROUND8(sizeof(UnpackedRecord)) + sizeof(Mem)*(pKeyInfo->nField+1); + if( nByte>szSpace+nOff ){ + p = (UnpackedRecord *)sqlite3DbMallocRaw(pKeyInfo->db, nByte); + *ppFree = (char *)p; + if( !p ) return 0; + }else{ + p = (UnpackedRecord*)&pSpace[nOff]; + *ppFree = 0; + } + + p->aMem = (Mem*)&((char*)p)[ROUND8(sizeof(UnpackedRecord))]; + p->pKeyInfo = pKeyInfo; + p->nField = pKeyInfo->nField + 1; + return p; +} + +/* +** Given the nKey-byte encoding of a record in pKey[], populate the +** UnpackedRecord structure indicated by the fourth argument with the +** contents of the decoded record. +*/ +void sqlite3VdbeRecordUnpack( + KeyInfo *pKeyInfo, /* Information about the record format */ + int nKey, /* Size of the binary record */ + const void *pKey, /* The binary record */ + UnpackedRecord *p /* Populate this structure before returning. */ +){ + const unsigned char *aKey = (const unsigned char *)pKey; + int d; + u32 idx; /* Offset in aKey[] to read from */ + u16 u; /* Unsigned loop counter */ + u32 szHdr; + Mem *pMem = p->aMem; + + p->flags = 0; + 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; // sqlite3VdbeSerialGet() will set this for us */ + pMem->zMalloc = 0; + d += sqlite3VdbeSerialGet(&aKey[d], serial_type, pMem); + pMem++; + u++; + } + assert( u<=pKeyInfo->nField + 1 ); + p->nField = u; +} + +/* +** 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 uninitialized, 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) ); + VVA_ONLY(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) ); + VVA_ONLY(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)); + } +} |