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53db145800a848b195c931eae71a173973f91620
sqlite/src/vdbeaux.c
T
drh 53db145800 sqlite3MemCompare now takes a CollSeq* argument. (CVS 1419) 
FossilOrigin-Name: 5c1e47a25244eacc69b688f5f4e62cec9f09665a
2004-05-20 13:54:53 +00:00

1762 lines
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C
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/*
** 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 "sqlite_vm" 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 "os.h"
#include <ctype.h>
#include "vdbeInt.h"
/*
** When debugging the code generator in a symbolic debugger, one can
** set the sqlite3_vdbe_addop_trace to 1 and all opcodes will be printed
** as they are added to the instruction stream.
*/
#ifndef NDEBUG
int sqlite3_vdbe_addop_trace = 0;
#endif
/*
** Create a new virtual database engine.
*/
Vdbe *sqlite3VdbeCreate(sqlite *db){
Vdbe *p;
p = sqliteMalloc( 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;
}
/*
** Turn tracing on or off
*/
void sqlite3VdbeTrace(Vdbe *p, FILE *trace){
p->trace = trace;
}
/*
** 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 First two of the three possible operands.
**
** Use the sqlite3VdbeResolveLabel() function to fix an address and
** the sqlite3VdbeChangeP3() function to change the value of the P3
** operand.
*/
int sqlite3VdbeAddOp(Vdbe *p, int op, int p1, int p2){
int i;
VdbeOp *pOp;
i = p->nOp;
p->nOp++;
assert( p->magic==VDBE_MAGIC_INIT );
if( i>=p->nOpAlloc ){
int oldSize = p->nOpAlloc;
Op *aNew;
p->nOpAlloc = p->nOpAlloc*2 + 100;
aNew = sqliteRealloc(p->aOp, p->nOpAlloc*sizeof(Op));
if( aNew==0 ){
p->nOpAlloc = oldSize;
return 0;
}
p->aOp = aNew;
memset(&p->aOp[oldSize], 0, (p->nOpAlloc-oldSize)*sizeof(Op));
}
pOp = &p->aOp[i];
pOp->opcode = op;
pOp->p1 = p1;
if( p2<0 && (-1-p2)<p->nLabel && p->aLabel[-1-p2]>=0 ){
p2 = p->aLabel[-1-p2];
}
pOp->p2 = p2;
pOp->p3 = 0;
pOp->p3type = P3_NOTUSED;
#ifndef NDEBUG
if( sqlite3_vdbe_addop_trace ) sqlite3VdbePrintOp(0, i, &p->aOp[i]);
#endif
return i;
}
/*
** Add an opcode that includes the p3 value.
*/
int sqlite3VdbeOp3(Vdbe *p, int op, int p1, int p2, const char *zP3, int p3type){
int addr = sqlite3VdbeAddOp(p, op, p1, p2);
sqlite3VdbeChangeP3(p, addr, zP3, p3type);
return addr;
}
/*
** Add multiple opcodes. The list is terminated by an opcode of 0.
*/
int sqlite3VdbeCode(Vdbe *p, ...){
int addr;
va_list ap;
int opcode, p1, p2;
va_start(ap, p);
addr = p->nOp;
while( (opcode = va_arg(ap,int))!=0 ){
p1 = va_arg(ap,int);
p2 = va_arg(ap,int);
sqlite3VdbeAddOp(p, opcode, p1, p2);
}
va_end(ap);
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.
*/
int sqlite3VdbeMakeLabel(Vdbe *p){
int i;
i = p->nLabel++;
assert( p->magic==VDBE_MAGIC_INIT );
if( i>=p->nLabelAlloc ){
int *aNew;
p->nLabelAlloc = p->nLabelAlloc*2 + 10;
aNew = sqliteRealloc( p->aLabel, p->nLabelAlloc*sizeof(p->aLabel[0]));
if( aNew==0 ){
sqliteFree(p->aLabel);
}
p->aLabel = aNew;
}
if( p->aLabel==0 ){
p->nLabel = 0;
p->nLabelAlloc = 0;
return 0;
}
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;
assert( p->magic==VDBE_MAGIC_INIT );
if( x<0 && (-x)<=p->nLabel && p->aOp ){
if( p->aLabel[-1-x]==p->nOp ) return;
assert( p->aLabel[-1-x]<0 );
p->aLabel[-1-x] = p->nOp;
for(j=0; j<p->nOp; j++){
if( p->aOp[j].p2==x ) p->aOp[j].p2 = p->nOp;
}
}
}
/*
** Return the address of the next instruction to be inserted.
*/
int sqlite3VdbeCurrentAddr(Vdbe *p){
assert( p->magic==VDBE_MAGIC_INIT );
return p->nOp;
}
/*
** 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 ){
int oldSize = p->nOpAlloc;
Op *aNew;
p->nOpAlloc = p->nOpAlloc*2 + nOp + 10;
aNew = sqliteRealloc(p->aOp, p->nOpAlloc*sizeof(Op));
if( aNew==0 ){
p->nOpAlloc = oldSize;
return 0;
}
p->aOp = aNew;
memset(&p->aOp[oldSize], 0, (p->nOpAlloc-oldSize)*sizeof(Op));
}
addr = p->nOp;
if( 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;
pOut->p2 = p2<0 ? addr + ADDR(p2) : p2;
pOut->p3 = pIn->p3;
pOut->p3type = pIn->p3 ? P3_STATIC : P3_NOTUSED;
#ifndef NDEBUG
if( sqlite3_vdbe_addop_trace ){
sqlite3VdbePrintOp(0, i+addr, &p->aOp[i+addr]);
}
#endif
}
p->nOp += nOp;
}
return addr;
}
/*
** Change the value of the P1 operand for a specific instruction.
** This routine is useful when a large program is loaded from a
** static array using sqlite3VdbeAddOpList but we want to make a
** few minor changes to the program.
*/
void sqlite3VdbeChangeP1(Vdbe *p, int addr, int val){
assert( p->magic==VDBE_MAGIC_INIT );
if( p && addr>=0 && p->nOp>addr && p->aOp ){
p->aOp[addr].p1 = val;
}
}
/*
** Change the value of the P2 operand for a specific instruction.
** This routine is useful for setting a jump destination.
*/
void sqlite3VdbeChangeP2(Vdbe *p, int addr, int val){
assert( val>=0 );
assert( p->magic==VDBE_MAGIC_INIT );
if( p && addr>=0 && p->nOp>addr && p->aOp ){
p->aOp[addr].p2 = val;
}
}
/*
** Change the value of the P3 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 P3 operand is dynamic, meaning that a copy of
** the string is made into memory obtained from sqliteMalloc().
** A value of n==0 means copy bytes of zP3 up to and including the
** first null byte. If n>0 then copy n+1 bytes of zP3.
**
** If n==P3_STATIC it means that zP3 is a pointer to a constant static
** string and we can just copy the pointer. n==P3_POINTER means zP3 is
** a pointer to some object other than a string.
**
** If addr<0 then change P3 on the most recently inserted instruction.
*/
void sqlite3VdbeChangeP3(Vdbe *p, int addr, const char *zP3, int n){
Op *pOp;
assert( p->magic==VDBE_MAGIC_INIT );
if( p==0 || p->aOp==0 ) return;
if( addr<0 || addr>=p->nOp ){
addr = p->nOp - 1;
if( addr<0 ) return;
}
pOp = &p->aOp[addr];
if( pOp->p3 && pOp->p3type==P3_DYNAMIC ){
sqliteFree(pOp->p3);
pOp->p3 = 0;
}
if( zP3==0 ){
pOp->p3 = 0;
pOp->p3type = P3_NOTUSED;
}else if( n<0 ){
pOp->p3 = (char*)zP3;
pOp->p3type = n;
}else{
sqlite3SetNString(&pOp->p3, zP3, n, 0);
pOp->p3type = P3_DYNAMIC;
}
}
/*
** If the P3 operand to the specified instruction appears
** to be a quoted string token, then this procedure removes
** the quotes.
**
** The quoting operator can be either a grave ascent (ASCII 0x27)
** or a double quote character (ASCII 0x22). Two quotes in a row
** resolve to be a single actual quote character within the string.
*/
void sqlite3VdbeDequoteP3(Vdbe *p, int addr){
Op *pOp;
assert( p->magic==VDBE_MAGIC_INIT );
if( p->aOp==0 ) return;
if( addr<0 || addr>=p->nOp ){
addr = p->nOp - 1;
if( addr<0 ) return;
}
pOp = &p->aOp[addr];
if( pOp->p3==0 || pOp->p3[0]==0 ) return;
if( pOp->p3type==P3_POINTER ) return;
if( pOp->p3type!=P3_DYNAMIC ){
pOp->p3 = sqliteStrDup(pOp->p3);
pOp->p3type = P3_DYNAMIC;
}
sqlite3Dequote(pOp->p3);
}
/*
** On the P3 argument of the given instruction, change all
** strings of whitespace characters into a single space and
** delete leading and trailing whitespace.
*/
void sqlite3VdbeCompressSpace(Vdbe *p, int addr){
unsigned char *z;
int i, j;
Op *pOp;
assert( p->magic==VDBE_MAGIC_INIT );
if( p->aOp==0 || addr<0 || addr>=p->nOp ) return;
pOp = &p->aOp[addr];
if( pOp->p3type==P3_POINTER ){
return;
}
if( pOp->p3type!=P3_DYNAMIC ){
pOp->p3 = sqliteStrDup(pOp->p3);
pOp->p3type = P3_DYNAMIC;
}
z = (unsigned char*)pOp->p3;
if( z==0 ) return;
i = j = 0;
while( isspace(z[i]) ){ i++; }
while( z[i] ){
if( isspace(z[i]) ){
z[j++] = ' ';
while( isspace(z[++i]) ){}
}else{
z[j++] = z[i++];
}
}
while( j>0 && isspace(z[j-1]) ){ j--; }
z[j] = 0;
}
/*
** Search the current program starting at instruction addr for the given
** opcode and P2 value. Return the address plus 1 if found and 0 if not
** found.
*/
int sqlite3VdbeFindOp(Vdbe *p, int addr, int op, int p2){
int i;
assert( p->magic==VDBE_MAGIC_INIT );
for(i=addr; i<p->nOp; i++){
if( p->aOp[i].opcode==op && p->aOp[i].p2==p2 ) return i+1;
}
return 0;
}
/*
** Return the opcode for a given address.
*/
VdbeOp *sqlite3VdbeGetOp(Vdbe *p, int addr){
assert( p->magic==VDBE_MAGIC_INIT );
assert( addr>=0 && addr<p->nOp );
return &p->aOp[addr];
}
/*
** The following group or routines are employed by installable functions
** to return their results.
**
** The sqlite3_set_result_string() routine can be used to return a string
** value or to return a NULL. To return a NULL, pass in NULL for zResult.
** A copy is made of the string before this routine returns so it is safe
** to pass in an ephemeral string.
**
** sqlite3_set_result_error() works like sqlite3_set_result_string() except
** that it signals a fatal error. The string argument, if any, is the
** error message. If the argument is NULL a generic substitute error message
** is used.
**
** The sqlite3_set_result_int() and sqlite3_set_result_double() set the return
** value of the user function to an integer or a double.
**
** These routines are defined here in vdbe.c because they depend on knowing
** the internals of the sqlite_func structure which is only defined in
** this source file.
*/
char *sqlite3_set_result_string(sqlite_func *p, const char *zResult, int n){
assert( !p->isStep );
if( p->s.flags & MEM_Dyn ){
sqliteFree(p->s.z);
}
if( zResult==0 ){
p->s.flags = MEM_Null;
n = 0;
p->s.z = 0;
p->s.n = 0;
}else{
if( n<0 ) n = strlen(zResult);
if( n<NBFS-1 ){
memcpy(p->s.zShort, zResult, n);
p->s.zShort[n] = 0;
p->s.flags = MEM_Str | MEM_Short;
p->s.z = p->s.zShort;
}else{
p->s.z = sqliteMallocRaw( n+1 );
if( p->s.z ){
memcpy(p->s.z, zResult, n);
p->s.z[n] = 0;
}
p->s.flags = MEM_Str | MEM_Dyn;
}
p->s.n = n+1;
}
return p->s.z;
}
void sqlite3_set_result_int(sqlite_func *p, int iResult){
assert( !p->isStep );
if( p->s.flags & MEM_Dyn ){
sqliteFree(p->s.z);
}
p->s.i = iResult;
p->s.flags = MEM_Int;
}
void sqlite3_set_result_double(sqlite_func *p, double rResult){
assert( !p->isStep );
if( p->s.flags & MEM_Dyn ){
sqliteFree(p->s.z);
}
p->s.r = rResult;
p->s.flags = MEM_Real;
}
void sqlite3_set_result_error(sqlite_func *p, const char *zMsg, int n){
assert( !p->isStep );
sqlite3_set_result_string(p, zMsg, n);
p->isError = 1;
}
/*
** Extract the user data from a sqlite_func structure and return a
** pointer to it.
*/
void *sqlite3_user_data(sqlite_func *p){
assert( p && p->pFunc );
return p->pFunc->pUserData;
}
/*
** Allocate or return the aggregate context for a user function. A new
** context is allocated on the first call. Subsequent calls return the
** same context that was returned on prior calls.
**
** This routine is defined here in vdbe.c because it depends on knowing
** the internals of the sqlite_func structure which is only defined in
** this source file.
*/
void *sqlite3_aggregate_context(sqlite_func *p, int nByte){
assert( p && p->pFunc && p->pFunc->xStep );
if( p->pAgg==0 ){
if( nByte<=NBFS ){
p->pAgg = (void*)p->s.z;
memset(p->pAgg, 0, nByte);
}else{
p->pAgg = sqliteMalloc( nByte );
}
}
return p->pAgg;
}
/*
** Return the number of times the Step function of a aggregate has been
** called.
**
** This routine is defined here in vdbe.c because it depends on knowing
** the internals of the sqlite_func structure which is only defined in
** this source file.
*/
int sqlite3_aggregate_count(sqlite_func *p){
assert( p && p->pFunc && p->pFunc->xStep );
return p->cnt;
}
#if !defined(NDEBUG) || defined(VDBE_PROFILE)
/*
** Print a single opcode. This routine is used for debugging only.
*/
void sqlite3VdbePrintOp(FILE *pOut, int pc, Op *pOp){
char *zP3;
char zPtr[40];
if( pOp->p3type==P3_POINTER ){
sprintf(zPtr, "ptr(%#x)", (int)pOp->p3);
zP3 = zPtr;
}else{
zP3 = pOp->p3;
}
if( pOut==0 ) pOut = stdout;
fprintf(pOut,"%4d %-12s %4d %4d %s\n",
pc, sqlite3OpcodeNames[pOp->opcode], pOp->p1, pOp->p2, zP3 ? zP3 : "");
fflush(pOut);
}
#endif
/*
** 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".
*/
int sqlite3VdbeList(
Vdbe *p /* The VDBE */
){
sqlite *db = p->db;
int i;
int rc = SQLITE_OK;
static char *azColumnNames[] = {
"addr", "opcode", "p1", "p2", "p3",
"int", "text", "int", "int", "text",
0
};
assert( p->popStack==0 );
assert( p->explain );
p->azColName = azColumnNames;
p->azResColumn = p->zArgv;
for(i=0; i<5; i++) p->zArgv[i] = p->aStack[i].zShort;
i = p->pc;
if( i>=p->nOp ){
p->rc = SQLITE_OK;
rc = SQLITE_DONE;
}else if( db->flags & SQLITE_Interrupt ){
db->flags &= ~SQLITE_Interrupt;
if( db->magic!=SQLITE_MAGIC_BUSY ){
p->rc = SQLITE_MISUSE;
}else{
p->rc = SQLITE_INTERRUPT;
}
rc = SQLITE_ERROR;
sqlite3SetString(&p->zErrMsg, sqlite3_error_string(p->rc), (char*)0);
}else{
sprintf(p->zArgv[0],"%d",i);
sprintf(p->zArgv[2],"%d", p->aOp[i].p1);
sprintf(p->zArgv[3],"%d", p->aOp[i].p2);
if( p->aOp[i].p3type==P3_POINTER ){
sprintf(p->aStack[4].zShort, "ptr(%#x)", (int)p->aOp[i].p3);
p->zArgv[4] = p->aStack[4].zShort;
}else{
p->zArgv[4] = p->aOp[i].p3;
}
p->zArgv[1] = sqlite3OpcodeNames[p->aOp[i].opcode];
p->pc = i+1;
p->azResColumn = p->zArgv;
p->nResColumn = 5;
p->rc = SQLITE_OK;
rc = SQLITE_ROW;
}
return rc;
}
/*
** Prepare a virtual machine for execution. This involves things such
** as allocating stack space and initializing the program counter.
** After the VDBE has be prepped, it can be executed by one or more
** calls to sqlite3VdbeExec().
*/
void sqlite3VdbeMakeReady(
Vdbe *p, /* The VDBE */
int nVar, /* Number of '?' see in the SQL statement */
int isExplain /* True if the EXPLAIN keywords is present */
){
int n;
assert( p!=0 );
assert( p->magic==VDBE_MAGIC_INIT );
/* Add a HALT instruction to the very end of the program.
*/
if( p->nOp==0 || (p->aOp && p->aOp[p->nOp-1].opcode!=OP_Halt) ){
sqlite3VdbeAddOp(p, OP_Halt, 0, 0);
}
/* No instruction ever pushes more than a single element onto the
** stack. And the stack never grows on successive executions of the
** same loop. So the total number of instructions is an upper bound
** on the maximum stack depth required.
**
** Allocation all the stack space we will ever need.
*/
if( p->aStack==0 ){
p->nVar = nVar;
assert( nVar>=0 );
n = isExplain ? 10 : p->nOp;
p->aStack = sqliteMalloc(
n*(sizeof(p->aStack[0]) + 2*sizeof(char*)) /* aStack and zArgv */
+ p->nVar*sizeof(Mem) /* apVar */
);
p->zArgv = (char**)&p->aStack[n];
p->azColName = (char**)&p->zArgv[n];
p->apVar = (Mem *)&p->azColName[n];
for(n=0; n<p->nVar; n++){
p->apVar[n].flags = MEM_Null;
}
}
sqlite3HashInit(&p->agg.hash, SQLITE_HASH_BINARY, 0);
p->agg.pSearch = 0;
#ifdef MEMORY_DEBUG
if( sqlite3OsFileExists("vdbe_trace") ){
p->trace = stdout;
}
#endif
p->pTos = &p->aStack[-1];
p->pc = 0;
p->rc = SQLITE_OK;
p->uniqueCnt = 0;
p->returnDepth = 0;
p->errorAction = OE_Abort;
p->undoTransOnError = 0;
p->popStack = 0;
p->explain |= isExplain;
p->magic = VDBE_MAGIC_RUN;
#ifdef VDBE_PROFILE
{
int i;
for(i=0; i<p->nOp; i++){
p->aOp[i].cnt = 0;
p->aOp[i].cycles = 0;
}
}
#endif
}
/*
** Remove any elements that remain on the sorter for the VDBE given.
*/
void sqlite3VdbeSorterReset(Vdbe *p){
while( p->pSort ){
Sorter *pSorter = p->pSort;
p->pSort = pSorter->pNext;
sqliteFree(pSorter->zKey);
sqliteFree(pSorter->pData);
sqliteFree(pSorter);
}
}
/*
** Reset an Agg structure. Delete all its contents.
**
** For installable aggregate functions, if the step function has been
** called, make sure the finalizer function has also been called. The
** finalizer might need to free memory that was allocated as part of its
** private context. If the finalizer has not been called yet, call it
** now.
*/
void sqlite3VdbeAggReset(Agg *pAgg){
int i;
HashElem *p;
for(p = sqliteHashFirst(&pAgg->hash); p; p = sqliteHashNext(p)){
AggElem *pElem = sqliteHashData(p);
assert( pAgg->apFunc!=0 );
for(i=0; i<pAgg->nMem; i++){
Mem *pMem = &pElem->aMem[i];
if( pAgg->apFunc[i] && (pMem->flags & MEM_AggCtx)!=0 ){
sqlite_func ctx;
ctx.pFunc = pAgg->apFunc[i];
ctx.s.flags = MEM_Null;
ctx.pAgg = pMem->z;
ctx.cnt = pMem->i;
ctx.isStep = 0;
ctx.isError = 0;
(*pAgg->apFunc[i]->xFinalize)(&ctx);
if( pMem->z!=0 && pMem->z!=pMem->zShort ){
sqliteFree(pMem->z);
}
if( ctx.s.flags & MEM_Dyn ){
sqliteFree(ctx.s.z);
}
}else if( pMem->flags & MEM_Dyn ){
sqliteFree(pMem->z);
}
}
sqliteFree(pElem);
}
sqlite3HashClear(&pAgg->hash);
sqliteFree(pAgg->apFunc);
pAgg->apFunc = 0;
pAgg->pCurrent = 0;
pAgg->pSearch = 0;
pAgg->nMem = 0;
}
/*
** Delete a keylist
*/
void sqlite3VdbeKeylistFree(Keylist *p){
while( p ){
Keylist *pNext = p->pNext;
sqliteFree(p);
p = pNext;
}
}
/*
** Close a cursor and release all the resources that cursor happens
** to hold.
*/
void sqlite3VdbeCleanupCursor(Cursor *pCx){
if( pCx->pCursor ){
sqlite3BtreeCloseCursor(pCx->pCursor);
}
if( pCx->pBt ){
sqlite3BtreeClose(pCx->pBt);
}
sqliteFree(pCx->pData);
sqliteFree(pCx->aType);
memset(pCx, 0, sizeof(*pCx));
}
/*
** Close all cursors
*/
static void closeAllCursors(Vdbe *p){
int i;
for(i=0; i<p->nCursor; i++){
Cursor *pC = p->apCsr[i];
sqlite3VdbeCleanupCursor(pC);
sqliteFree(pC);
}
sqliteFree(p->apCsr);
p->apCsr = 0;
p->nCursor = 0;
}
/*
** 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){
int i;
if( p->aStack ){
Mem *pTos = p->pTos;
while( pTos>=p->aStack ){
if( pTos->flags & MEM_Dyn ){
sqliteFree(pTos->z);
}
pTos--;
}
p->pTos = pTos;
}
closeAllCursors(p);
if( p->aMem ){
for(i=0; i<p->nMem; i++){
if( p->aMem[i].flags & MEM_Dyn ){
sqliteFree(p->aMem[i].z);
}
}
}
sqliteFree(p->aMem);
p->aMem = 0;
p->nMem = 0;
if( p->pList ){
sqlite3VdbeKeylistFree(p->pList);
p->pList = 0;
}
sqlite3VdbeSorterReset(p);
if( p->pFile ){
if( p->pFile!=stdin ) fclose(p->pFile);
p->pFile = 0;
}
if( p->azField ){
sqliteFree(p->azField);
p->azField = 0;
}
p->nField = 0;
if( p->zLine ){
sqliteFree(p->zLine);
p->zLine = 0;
}
p->nLineAlloc = 0;
sqlite3VdbeAggReset(&p->agg);
if( p->aSet ){
for(i=0; i<p->nSet; i++){
sqlite3HashClear(&p->aSet[i].hash);
}
}
sqliteFree(p->aSet);
p->aSet = 0;
p->nSet = 0;
if( p->keylistStack ){
int ii;
for(ii = 0; ii < p->keylistStackDepth; ii++){
sqlite3VdbeKeylistFree(p->keylistStack[ii]);
}
sqliteFree(p->keylistStack);
p->keylistStackDepth = 0;
p->keylistStack = 0;
}
sqliteFree(p->contextStack);
p->contextStack = 0;
sqliteFree(p->zErrMsg);
p->zErrMsg = 0;
}
/*
** 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.
*/
int sqlite3VdbeReset(Vdbe *p, char **pzErrMsg){
sqlite *db = p->db;
int i;
if( p->magic!=VDBE_MAGIC_RUN && p->magic!=VDBE_MAGIC_HALT ){
sqlite3SetString(pzErrMsg, sqlite3_error_string(SQLITE_MISUSE), (char*)0);
return SQLITE_MISUSE;
}
if( p->zErrMsg ){
if( pzErrMsg && *pzErrMsg==0 ){
*pzErrMsg = p->zErrMsg;
}else{
sqliteFree(p->zErrMsg);
}
p->zErrMsg = 0;
}else if( p->rc ){
sqlite3SetString(pzErrMsg, sqlite3_error_string(p->rc), (char*)0);
}
Cleanup(p);
if( p->rc!=SQLITE_OK ){
switch( p->errorAction ){
case OE_Abort: {
if( !p->undoTransOnError ){
for(i=0; i<db->nDb; i++){
if( db->aDb[i].pBt ){
sqlite3BtreeRollbackStmt(db->aDb[i].pBt);
}
}
break;
}
/* Fall through to ROLLBACK */
}
case OE_Rollback: {
sqlite3RollbackAll(db);
db->flags &= ~SQLITE_InTrans;
db->onError = OE_Default;
break;
}
default: {
if( p->undoTransOnError ){
sqlite3RollbackAll(db);
db->flags &= ~SQLITE_InTrans;
db->onError = OE_Default;
}
break;
}
}
sqlite3RollbackInternalChanges(db);
}
for(i=0; i<db->nDb; i++){
if( db->aDb[i].pBt && db->aDb[i].inTrans==2 ){
sqlite3BtreeCommitStmt(db->aDb[i].pBt);
db->aDb[i].inTrans = 1;
}
}
assert( p->pTos<&p->aStack[p->pc] || sqlite3_malloc_failed==1 );
#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;
}
/*
** 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, char **pzErrMsg){
int rc;
sqlite *db;
if( p->magic!=VDBE_MAGIC_RUN && p->magic!=VDBE_MAGIC_HALT ){
sqlite3SetString(pzErrMsg, sqlite3_error_string(SQLITE_MISUSE), (char*)0);
return SQLITE_MISUSE;
}
db = p->db;
rc = sqlite3VdbeReset(p, pzErrMsg);
sqlite3VdbeDelete(p);
if( db->want_to_close && db->pVdbe==0 ){
sqlite3_close(db);
}
if( rc==SQLITE_SCHEMA ){
sqlite3ResetInternalSchema(db, 0);
}
return rc;
}
/*
** Unbind the value bound to variable $i in virtual machine p. This is the
** the same as binding a NULL value to the column. If the "i" parameter is
** out of range, then SQLITE_RANGE is returned. Othewise SQLITE_OK.
**
** The error code stored in database p->db is overwritten with the return
** value in any case.
*/
static int vdbeUnbind(Vdbe *p, int i){
Mem *pVar;
if( p->magic!=VDBE_MAGIC_RUN || p->pc!=0 ){
sqlite3Error(p->db, SQLITE_MISUSE, 0);
return SQLITE_MISUSE;
}
if( i<1 || i>p->nVar ){
sqlite3Error(p->db, SQLITE_RANGE, 0);
return SQLITE_RANGE;
}
i--;
pVar = &p->apVar[i];
if( pVar->flags&MEM_Dyn ){
sqliteFree(pVar->z);
}
pVar->flags = MEM_Null;
sqlite3Error(p->db, SQLITE_OK, 0);
return SQLITE_OK;
}
/*
** This routine is used to bind text or blob data to an SQL variable (a ?).
** It may also be used to bind a NULL value, by setting zVal to 0. Any
** existing value is unbound.
**
** The error code stored in p->db is overwritten with the return value in
** all cases.
*/
static int vdbeBindBlob(
Vdbe *p, /* Virtual machine */
int i, /* Var number to bind (numbered from 1 upward) */
const char *zVal, /* Pointer to blob of data */
int bytes, /* Number of bytes to copy */
int copy, /* True to copy the memory, false to copy a pointer */
int flags /* Valid combination of MEM_Blob, MEM_Str, MEM_UtfXX */
){
Mem *pVar;
int rc;
rc = vdbeUnbind(p, i);
if( rc!=SQLITE_OK ){
return rc;
}
pVar = &p->apVar[i-1];
if( zVal ){
pVar->n = bytes;
pVar->flags = flags;
if( !copy ){
pVar->z = (char *)zVal;
pVar->flags |= MEM_Static;
}else{
if( bytes>NBFS ){
pVar->z = (char *)sqliteMalloc(bytes);
if( !pVar->z ){
sqlite3Error(p->db, SQLITE_NOMEM, 0);
return SQLITE_NOMEM;
}
pVar->flags |= MEM_Dyn;
}else{
pVar->z = pVar->zShort;
pVar->flags |= MEM_Short;
}
memcpy(pVar->z, zVal, bytes);
}
}
return SQLITE_OK;
}
/*
** Bind a 64 bit integer to an SQL statement variable.
*/
int sqlite3_bind_int64(sqlite3_stmt *p, int i, long long int iValue){
int rc;
Vdbe *v = (Vdbe *)p;
rc = vdbeUnbind(v, i);
if( rc==SQLITE_OK ){
Mem *pVar = &v->apVar[i-1];
pVar->flags = MEM_Int;
pVar->i = iValue;
}
return SQLITE_OK;
}
/*
** Bind a 32 bit integer to an SQL statement variable.
*/
int sqlite3_bind_int32(sqlite3_stmt *p, int i, int iValue){
return sqlite3_bind_int64(p, i, (long long int)iValue);
}
/*
** Bind a double (real) to an SQL statement variable.
*/
int sqlite3_bind_double(sqlite3_stmt *p, int i, double iValue){
int rc;
Vdbe *v = (Vdbe *)p;
rc = vdbeUnbind(v, i);
if( rc==SQLITE_OK ){
Mem *pVar = &v->apVar[i-1];
pVar->flags = MEM_Real;
pVar->r = iValue;
}
return SQLITE_OK;
}
/*
** Bind a NULL value to an SQL statement variable.
*/
int sqlite3_bind_null(sqlite3_stmt* p, int i){
return vdbeUnbind((Vdbe *)p, i);
}
/*
** Bind a UTF-8 text value to an SQL statement variable.
*/
int sqlite3_bind_text(
sqlite3_stmt *p,
int i,
const char *zData,
int nData,
int eCopy
){
int flags = MEM_Str|MEM_Utf8;
if( zData ){
if( nData<0 ){
nData = strlen(zData)+1;
flags |= MEM_Term;
}else if( !zData[nData-1] ){
flags |= MEM_Term;
}
}
return vdbeBindBlob((Vdbe *)p, i, zData, nData, eCopy, flags);
}
/*
** Bind a UTF-16 text value to an SQL statement variable.
*/
int sqlite3_bind_text16(
sqlite3_stmt *p,
int i,
const void *zData,
int nData,
int eCopy
){
int flags = MEM_Str|MEM_Utf16le|MEM_Utf16be;
if( zData ){
/* If nData is less than zero, measure the length of the string.
** manually. In this case the variable will always be null terminated.
*/
if( nData<0 ){
nData = sqlite3utf16ByteLen(zData, -1) + 2;
flags |= MEM_Term;
}else{
/* If nData is greater than zero, check if the final character appears
** to be a terminator.
*/
if( !(((u8 *)zData)[nData-1]) && !(((u8 *)zData)[nData-2]) ){
flags |= MEM_Term;
}
}
}
return vdbeBindBlob((Vdbe *)p, i, zData, nData, eCopy, flags);
}
/*
** Bind a blob value to an SQL statement variable.
*/
int sqlite3_bind_blob(
sqlite3_stmt *p,
int i,
const void *zData,
int nData,
int eCopy
){
return vdbeBindBlob((Vdbe *)p, i, zData, nData, eCopy, MEM_Blob);
}
/*
** Set the values of all variables. Variable $1 in the original SQL will
** be the string azValue[0]. $2 will have the value azValue[1]. And
** so forth. If a value is out of range (for example $3 when nValue==2)
** then its value will be NULL.
**
** This routine overrides any prior call.
*/
int sqlite3_bind(sqlite_vm *pVm, int i, const char *zVal, int len, int copy){
return sqlite3_bind_text(pVm, i, zVal, len, copy);
}
/*
** Delete an entire VDBE.
*/
void sqlite3VdbeDelete(Vdbe *p){
int i;
if( p==0 ) return;
Cleanup(p);
if( p->pPrev ){
p->pPrev->pNext = p->pNext;
}else{
assert( p->db->pVdbe==p );
p->db->pVdbe = p->pNext;
}
if( p->pNext ){
p->pNext->pPrev = p->pPrev;
}
p->pPrev = p->pNext = 0;
if( p->nOpAlloc==0 ){
p->aOp = 0;
p->nOp = 0;
}
for(i=0; i<p->nOp; i++){
if( p->aOp[i].p3type==P3_DYNAMIC ){
sqliteFree(p->aOp[i].p3);
}
}
for(i=0; i<p->nVar; i++){
if( p->apVar[i].flags&MEM_Dyn ){
sqliteFree(p->apVar[i].z);
}
}
sqliteFree(p->aOp);
sqliteFree(p->aLabel);
sqliteFree(p->aStack);
p->magic = VDBE_MAGIC_DEAD;
sqliteFree(p);
}
/*
** If a MoveTo operation is pending on the given cursor, then do that
** MoveTo now. Return an error code. If no MoveTo is pending, this
** routine does nothing and returns SQLITE_OK.
*/
int sqlite3VdbeCursorMoveto(Cursor *p){
if( p->deferredMoveto ){
int res;
extern int sqlite3_search_count;
assert( p->intKey );
if( p->intKey ){
sqlite3BtreeMoveto(p->pCursor, 0, p->movetoTarget, &res);
}else{
sqlite3BtreeMoveto(p->pCursor,(char*)&p->movetoTarget,sizeof(i64),&res);
}
p->incrKey = 0;
p->lastRecno = keyToInt(p->movetoTarget);
p->recnoIsValid = res==0;
if( res<0 ){
sqlite3BtreeNext(p->pCursor, &res);
}
sqlite3_search_count++;
p->deferredMoveto = 0;
p->cacheValid = 0;
}
return SQLITE_OK;
}
/*
** The following functions:
**
** sqlite3VdbeSerialType()
** sqlite3VdbeSerialTypeLen()
** sqlite3VdbeSerialRead()
** sqlite3VdbeSerialLen()
** sqlite3VdbeSerialWrite()
**
** 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 - Not a type.
** 1 1 signed integer
** 2 2 signed integer
** 3 4 signed integer
** 4 8 signed integer
** 5 8 IEEE float
** 6 0 NULL
** 7..11 reserved for expansion
** N>=12 and even (N-12)/2 BLOB
** N>=13 and odd (N-13)/2 text
**
*/
/*
** Return the serial-type for the value stored in pMem.
*/
u64 sqlite3VdbeSerialType(const Mem *pMem){
int flags = pMem->flags;
if( flags&MEM_Null ){
return 6;
}
if( flags&MEM_Int ){
/* Figure out whether to use 1, 2, 4 or 8 bytes. */
i64 i = pMem->i;
if( i>=-127 && i<=127 ) return 1;
if( i>=-32767 && i<=32767 ) return 2;
if( i>=-2147483647 && i<=2147483647 ) return 3;
return 4;
}
if( flags&MEM_Real ){
return 5;
}
if( flags&MEM_Str ){
/* We assume that the string is NULL-terminated. We don't store the
** NULL-terminator - it is implied by the string storage class.
*/
assert( pMem->n>0 );
assert( pMem->z[pMem->n-1]=='\0' );
return (pMem->n*2 + 11); /* (pMem->n-1)*2 + 13 */
}
if( flags&MEM_Blob ){
return (pMem->n*2 + 12);
}
return 0;
}
/*
** Return the length of the data corresponding to the supplied serial-type.
*/
int sqlite3VdbeSerialTypeLen(u64 serial_type){
assert( serial_type!=0 );
switch(serial_type){
case 6: return 0; /* NULL */
case 1: return 1; /* 1 byte integer */
case 2: return 2; /* 2 byte integer */
case 3: return 4; /* 4 byte integer */
case 4: return 8; /* 8 byte integer */
case 5: return 8; /* 8 byte float */
}
assert( serial_type>=12 );
return ((serial_type-12)>>1); /* text or blob */
}
/*
** 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.
*/
int sqlite3VdbeSerialPut(unsigned char *buf, const Mem *pMem){
u64 serial_type = sqlite3VdbeSerialType(pMem);
int len;
assert( serial_type!=0 );
/* NULL */
if( serial_type==6 ){
return 0;
}
/* Integer */
if( serial_type<5 ){
i64 i = pMem->i;
len = sqlite3VdbeSerialTypeLen(serial_type);
while( len-- ){
buf[len] = (i&0xFF);
i = i >> 8;
}
return sqlite3VdbeSerialTypeLen(serial_type);
}
/* Float */
if( serial_type==5 ){
/* TODO: byte ordering? */
assert( sizeof(double)==8 );
memcpy(buf, &pMem->r, 8);
return 8;
}
/* String or blob */
assert( serial_type>=12 );
len = sqlite3VdbeSerialTypeLen(serial_type);
memcpy(buf, pMem->z, len);
return len;
}
/*
** 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.
*/
int sqlite3VdbeSerialGet(const unsigned char *buf, u64 serial_type, Mem *pMem){
int len;
assert( serial_type!=0 );
/* memset(pMem, 0, sizeof(pMem)); */
pMem->flags = 0;
pMem->z = 0;
/* NULL */
if( serial_type==6 ){
pMem->flags = MEM_Null;
return 0;
}
/* Integer */
if( serial_type<5 ){
i64 i = 0;
int n;
len = sqlite3VdbeSerialTypeLen(serial_type);
if( buf[0]&0x80 ){
for(n=0; n<(8-len); n++){
i = (i<<8)+0xFF;
}
}
for(n=0; n<len; n++){
i = i << 8;
i = i + buf[n];
}
pMem->flags = MEM_Int;
pMem->i = i;
return sqlite3VdbeSerialTypeLen(serial_type);
}
/* Float */
if( serial_type==5 ){
/* TODO: byte ordering? */
assert( sizeof(double)==8 );
memcpy(&pMem->r, buf, 8);
pMem->flags = MEM_Real;
return 8;
}
/* String or blob */
assert( serial_type>=12 );
len = sqlite3VdbeSerialTypeLen(serial_type);
if( serial_type&0x01 ){
pMem->flags = MEM_Str;
pMem->n = len+1;
}else{
pMem->flags = MEM_Blob;
pMem->n = len;
}
if( (pMem->n)>NBFS ){
pMem->z = sqliteMallocRaw( pMem->n );
if( !pMem->z ){
return -1;
}
pMem->flags |= MEM_Dyn;
}else{
pMem->z = pMem->zShort;
pMem->flags |= MEM_Short;
}
memcpy(pMem->z, buf, len);
if( pMem->flags&MEM_Str ){
pMem->z[len] = '\0';
}
return len;
}
/*
** Compare the values contained by the two memory cells, returning
** negative, zero or positive if pMem1 is less than, equal to, or greater
** than pMem2. Sorting order is NULL's first, followed by numbers (integers
** and reals) sorted numerically, followed by text ordered by memcmp() and
** finally blob's ordered by memcmp().
**
** Two NULL values are considered equal by this function.
*/
int sqlite3MemCompare(const Mem *pMem1, const Mem *pMem2, const CollSeq *pColl){
int rc;
int f1, f2;
int combined_flags;
/* Interchange pMem1 and pMem2 if the collating sequence specifies
** DESC order.
*/
if( pColl && pColl->reverseOrder ){
const Mem *pTemp = pMem1;
pMem1 = pMem2;
pMem2 = pTemp;
}
f1 = pMem1->flags;
f2 = pMem2->flags;
combined_flags = f1|f2;
/* If one value is NULL, it is less than the other. If both values
** are NULL, return 0.
*/
if( combined_flags&MEM_Null ){
return (f2&MEM_Null) - (f1&MEM_Null);
}
/* If one value is a number and the other is not, the number is less.
** If both are numbers, compare as reals if one is a real, or as integers
** if both values are integers.
*/
if( combined_flags&(MEM_Int|MEM_Real) ){
if( !(f1&(MEM_Int|MEM_Real)) ){
return 1;
}
if( !(f2&(MEM_Int|MEM_Real)) ){
return -1;
}
if( (f1 & f2 & MEM_Int)==0 ){
double r1, r2;
if( (f1&MEM_Real)==0 ){
r1 = pMem1->i;
}else{
r1 = pMem1->r;
}
if( (f2&MEM_Real)==0 ){
r2 = pMem2->i;
}else{
r2 = pMem2->r;
}
if( r1<r2 ) return -1;
if( r1>r2 ) return 1;
return 0;
}else{
assert( f1&MEM_Int );
assert( f2&MEM_Int );
if( pMem1->i < pMem2->i ) return -1;
if( pMem1->i > pMem2->i ) return 1;
return 0;
}
}
/* If one value is a string and the other is a blob, the string is less.
** If both are strings, compare using the collating functions.
*/
if( combined_flags&MEM_Str ){
if( (f1 & MEM_Str)==0 ){
return 1;
}
if( (f2 & MEM_Str)==0 ){
return -1;
}
if( pColl && pColl->xCmp ){
return pColl->xCmp(pColl->pUser, pMem1->n, pMem1->z, pMem2->n, pMem2->z);
}else{
/* If no collating sequence is defined, fall through into the
** blob case below and use memcmp() for the comparison. */
}
}
/* Both values must be blobs. Compare using memcmp().
*/
rc = memcmp(pMem1->z, pMem2->z, (pMem1->n>pMem2->n)?pMem2->n:pMem1->n);
if( rc==0 ){
rc = pMem1->n - pMem2->n;
}
return rc;
}
/*
** The following is the comparison function for (non-integer)
** keys in the btrees. This function returns negative, zero, or
** positive if the first key is less than, equal to, or greater than
** the second.
**
** This function assumes that each key consists of one or more type/blob
** pairs, encoded using the sqlite3VdbeSerialXXX() functions above.
**
** Following the type/blob pairs, each key may have a single 0x00 byte
** followed by a varint. A key may only have this traling 0x00/varint
** pair if it has at least as many type/blob pairs as the key it is being
** compared to.
*/
int sqlite3VdbeKeyCompare(
void *userData,
int nKey1, const void *pKey1,
int nKey2, const void *pKey2
){
Cursor *pC = (Cursor *)userData;
int offset1 = 0;
int offset2 = 0;
const unsigned char *aKey1 = (const unsigned char *)pKey1;
const unsigned char *aKey2 = (const unsigned char *)pKey2;
while( offset1<nKey1 && offset2<nKey2 ){
Mem mem1;
Mem mem2;
u64 serial_type1;
u64 serial_type2;
int rc;
/* Read the serial types for the next element in each key. */
offset1 += sqlite3GetVarint(&aKey1[offset1], &serial_type1);
offset2 += sqlite3GetVarint(&aKey2[offset2], &serial_type2);
/* If either of the varints just read in are 0 (not a type), then
** this is the end of the keys. The remaining data in each key is
** the varint rowid. Compare these as signed integers and return
** the result.
*/
if( !serial_type1 || !serial_type2 ){
assert( !serial_type1 && !serial_type2 );
assert( !pC || !pC->incrKey );
sqlite3GetVarint(&aKey1[offset1], &serial_type1);
sqlite3GetVarint(&aKey2[offset2], &serial_type2);
return ( (i64)serial_type1 - (i64)serial_type2 );
}
/* Assert that there is enough space left in each key for the blob of
** data to go with the serial type just read. This assert may fail if
** the file is corrupted. Then read the value from each key into mem1
** and mem2 respectively.
*/
offset1 += sqlite3VdbeSerialGet(&aKey1[offset1], serial_type1, &mem1);
offset2 += sqlite3VdbeSerialGet(&aKey2[offset2], serial_type2, &mem2);
rc = sqlite3MemCompare(&mem1, &mem2, 0);
if( mem1.flags&MEM_Dyn ){
sqliteFree(mem1.z);
}
if( mem2.flags&MEM_Dyn ){
sqliteFree(mem2.z);
}
if( rc!=0 ){
return rc;
}
}
/* One of the keys ran out of fields, but all the fields up to that point
** were equal. If the incrKey flag is true, then the second key is
** treated as larger.
*/
if( pC && pC->incrKey ){
assert( offset2==nKey2 );
return -1;
}
if( offset1<nKey1 ){
return 1;
}
if( offset2<nKey2 ){
return -1;
}
return 0;
}
/*
** This function compares the two table row records specified by
** {nKey1, pKey1} and {nKey2, pKey2}, returning a negative, zero
** or positive integer if {nKey1, pKey1} is less than, equal to or
** greater than {nKey2, pKey2}.
**
** This function is pretty inefficient and will probably be replaced
** by something else in the near future. It is currently required
** by compound SELECT operators.
*/
int sqlite3VdbeRowCompare(
void *userData,
int nKey1, const void *pKey1,
int nKey2, const void *pKey2
){
Cursor *pC = (Cursor *)userData;
int offset1 = 0;
int offset2 = 0;
int toffset1 = 0;
int toffset2 = 0;
int i;
const unsigned char *aKey1 = (const unsigned char *)pKey1;
const unsigned char *aKey2 = (const unsigned char *)pKey2;
assert( pC );
assert( pC->nField>0 );
for( i=0; i<pC->nField; i++ ){
u64 dummy;
offset1 += sqlite3GetVarint(&aKey1[offset1], &dummy);
offset2 += sqlite3GetVarint(&aKey1[offset1], &dummy);
}
for( i=0; i<pC->nField; i++ ){
Mem mem1;
Mem mem2;
u64 serial_type1;
u64 serial_type2;
int rc;
/* Read the serial types for the next element in each key. */
toffset1 += sqlite3GetVarint(&aKey1[toffset1], &serial_type1);
toffset2 += sqlite3GetVarint(&aKey2[toffset2], &serial_type2);
assert( serial_type1 && serial_type2 );
/* Assert that there is enough space left in each key for the blob of
** data to go with the serial type just read. This assert may fail if
** the file is corrupted. Then read the value from each key into mem1
** and mem2 respectively.
*/
offset1 += sqlite3VdbeSerialGet(&aKey1[offset1], serial_type1, &mem1);
offset2 += sqlite3VdbeSerialGet(&aKey2[offset2], serial_type2, &mem2);
rc = sqlite3MemCompare(&mem1, &mem2, 0);
if( mem1.flags&MEM_Dyn ){
sqliteFree(mem1.z);
}
if( mem2.flags&MEM_Dyn ){
sqliteFree(mem2.z);
}
if( rc!=0 ){
return rc;
}
}
return 0;
}
/*
** pCur points at an index entry. Read the rowid (varint occuring at
** the end of the entry and store it in *rowid. Return SQLITE_OK if
** everything works, or an error code otherwise.
*/
int sqlite3VdbeIdxRowid(BtCursor *pCur, i64 *rowid){
i64 sz;
int rc;
char buf[10];
int len;
u64 r;
rc = sqlite3BtreeKeySize(pCur, &sz);
if( rc!=SQLITE_OK ){
return rc;
}
len = ((sz>10)?10:sz);
/* If there are less than 2 bytes in the key, this cannot be
** a valid index entry. In practice this comes up for a query
** of the sort "SELECT max(x) FROM t1;" when t1 is an empty table
** with an index on x. In this case just call the rowid 0.
*/
if( len<2 ){
*rowid = 0;
return SQLITE_OK;
}
rc = sqlite3BtreeKey(pCur, sz-len, len, buf);
if( rc!=SQLITE_OK ){
return rc;
}
len--;
while( buf[len-1] && --len );
sqlite3GetVarint(&buf[len], &r);
*rowid = r;
return SQLITE_OK;
}
/*
** Compare the key of index entry that cursor pC is point to against
** the key string in pKey (of length nKey). Write into *pRes a number
** that is negative, zero, or positive if pC is less than, equal to,
** or greater than pKey. Return SQLITE_OK on success.
*/
int sqlite3VdbeIdxKeyCompare(
Cursor *pC, /* The cursor to compare against */
int nKey, const u8 *pKey, /* The key to compare */
int *res /* Write the comparison result here */
){
unsigned char *pCellKey;
u64 nCellKey;
int freeCellKey = 0;
int rc;
int len;
BtCursor *pCur = pC->pCursor;
sqlite3BtreeKeySize(pCur, &nCellKey);
if( nCellKey<=0 ){
*res = 0;
return SQLITE_OK;
}
pCellKey = (unsigned char *)sqlite3BtreeKeyFetch(pCur, nCellKey);
if( !pCellKey ){
pCellKey = (unsigned char *)sqliteMallocRaw(nCellKey);
if( !pCellKey ){
return SQLITE_NOMEM;
}
freeCellKey = 1;
rc = sqlite3BtreeKey(pCur, 0, nCellKey, pCellKey);
if( rc!=SQLITE_OK ){
sqliteFree(pCellKey);
return rc;
}
}
len = nCellKey-2;
while( pCellKey[len] && --len );
*res = sqlite3VdbeKeyCompare(pC, len, pCellKey, nKey, pKey);
if( freeCellKey ){
sqliteFree(pCellKey);
}
return SQLITE_OK;
}
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