root/campo-sirio
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity
campo-sirio/sqlite/vdbeaux.c
guy e883f21fe8 Patch level : 2.2 
Files correlati     : sqlite
Ricompilazione Demo : [ ]
Commento            :
Passaggio da Sqlite 2 a Sqlite 3.3.5


git-svn-id: svn://10.65.10.50/trunk@13902 c028cbd2-c16b-5b4b-a496-9718f37d4682
2006-04-13 12:44:29 +00:00

1976 lines
57 KiB
C
Executable File
Raw Blame History

/*
** 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 "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.
*/
#ifdef SQLITE_DEBUG
int sqlite3_vdbe_addop_trace = 0;
#endif
/*
** Create a new virtual database engine.
*/
Vdbe *sqlite3VdbeCreate(sqlite3 *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;
}
/*
** Resize the Vdbe.aOp array so that it contains at least N
** elements. If the Vdbe is in VDBE_MAGIC_RUN state, then
** the Vdbe.aOp array will be sized to contain exactly N
** elements. Vdbe.nOpAlloc is set to reflect the new size of
** the array.
**
** If an out-of-memory error occurs while resizing the array,
** 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 void resizeOpArray(Vdbe *p, int N){
int runMode = p->magic==VDBE_MAGIC_RUN;
if( runMode || p->nOpAlloc<N ){
VdbeOp *pNew;
int nNew = N + 100*(!runMode);
int oldSize = p->nOpAlloc;
pNew = sqliteRealloc(p->aOp, nNew*sizeof(Op));
if( pNew ){
p->nOpAlloc = nNew;
p->aOp = pNew;
if( nNew>oldSize ){
memset(&p->aOp[oldSize], 0, (nNew-oldSize)*sizeof(Op));
}
}
}
}
/*
** 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( p->nOpAlloc<=i ){
resizeOpArray(p, i+1);
if( sqlite3MallocFailed() ){
return 0;
}
}
pOp = &p->aOp[i];
pOp->opcode = op;
pOp->p1 = p1;
pOp->p2 = p2;
pOp->p3 = 0;
pOp->p3type = P3_NOTUSED;
p->expired = 0;
#ifdef SQLITE_DEBUG
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;
}
/*
** 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 ){
p->nLabelAlloc = p->nLabelAlloc*2 + 10;
sqliteReallocOrFree((void**)&p->aLabel,
p->nLabelAlloc*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;
}
}
/*
** Return non-zero if opcode 'op' is guarenteed not to push more values
** onto the VDBE stack than it pops off.
*/
static int opcodeNoPush(u8 op){
/* The 10 NOPUSH_MASK_n constants are defined in the automatically
** generated header file opcodes.h. Each is a 16-bit bitmask, one
** bit corresponding to each opcode implemented by the virtual
** machine in vdbe.c. The bit is true if the word "no-push" appears
** in a comment on the same line as the "case OP_XXX:" in
** sqlite3VdbeExec() in vdbe.c.
**
** If the bit is true, then the corresponding opcode is guarenteed not
** to grow the stack when it is executed. Otherwise, it may grow the
** stack by at most one entry.
**
** NOPUSH_MASK_0 corresponds to opcodes 0 to 15. NOPUSH_MASK_1 contains
** one bit for opcodes 16 to 31, and so on.
**
** 16-bit bitmasks (rather than 32-bit) are specified in opcodes.h
** because the file is generated by an awk program. Awk manipulates
** all numbers as floating-point and we don't want to risk a rounding
** error if someone builds with an awk that uses (for example) 32-bit
** IEEE floats.
*/
static const u32 masks[5] = {
NOPUSH_MASK_0 + (((unsigned)NOPUSH_MASK_1)<<16),
NOPUSH_MASK_2 + (((unsigned)NOPUSH_MASK_3)<<16),
NOPUSH_MASK_4 + (((unsigned)NOPUSH_MASK_5)<<16),
NOPUSH_MASK_6 + (((unsigned)NOPUSH_MASK_7)<<16),
NOPUSH_MASK_8 + (((unsigned)NOPUSH_MASK_9)<<16)
};
assert( op<32*5 );
return (masks[op>>5] & (1<<(op&0x1F)));
}
#ifndef NDEBUG
int sqlite3VdbeOpcodeNoPush(u8 op){
return opcodeNoPush(op);
}
#endif
/*
** Loop through the program looking for P2 values that are negative.
** 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 or OP_AggStep opcode. This is used by
** sqlite3VdbeMakeReady() to size the Vdbe.apArg[] array.
**
** The integer *pMaxStack is set to the maximum number of vdbe stack
** entries that static analysis reveals this program might need.
**
** This routine also does the following optimization: It scans for
** Halt instructions where P1==SQLITE_CONSTRAINT or P2==OE_Abort or for
** IdxInsert instructions where P2!=0. If no such instruction is
** found, then every Statement instruction is changed to a Noop. In
** this way, we avoid creating the statement journal file unnecessarily.
*/
static void resolveP2Values(Vdbe *p, int *pMaxFuncArgs, int *pMaxStack){
int i;
int nMaxArgs = 0;
int nMaxStack = p->nOp;
Op *pOp;
int *aLabel = p->aLabel;
int doesStatementRollback = 0;
int hasStatementBegin = 0;
for(pOp=p->aOp, i=p->nOp-1; i>=0; i--, pOp++){
u8 opcode = pOp->opcode;
if( opcode==OP_Function || opcode==OP_AggStep ){
if( pOp->p2>nMaxArgs ) nMaxArgs = pOp->p2;
}else if( opcode==OP_Halt ){
if( pOp->p1==SQLITE_CONSTRAINT && pOp->p2==OE_Abort ){
doesStatementRollback = 1;
}
}else if( opcode==OP_IdxInsert ){
if( pOp->p2 ){
doesStatementRollback = 1;
}
}else if( opcode==OP_Statement ){
hasStatementBegin = 1;
}
if( opcodeNoPush(opcode) ){
nMaxStack--;
}
if( pOp->p2>=0 ) continue;
assert( -1-pOp->p2<p->nLabel );
pOp->p2 = aLabel[-1-pOp->p2];
}
sqliteFree(p->aLabel);
p->aLabel = 0;
*pMaxFuncArgs = nMaxArgs;
*pMaxStack = nMaxStack;
/* If we never rollback a statement transaction, then statement
** transactions are not needed. So change every OP_Statement
** opcode into an OP_Noop. This avoid a call to sqlite3OsOpenExclusive()
** which can be expensive on some platforms.
*/
if( hasStatementBegin && !doesStatementRollback ){
for(pOp=p->aOp, i=p->nOp-1; i>=0; i--, pOp++){
if( pOp->opcode==OP_Statement ){
pOp->opcode = OP_Noop;
}
}
}
}
/*
** 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 );
resizeOpArray(p, p->nOp + nOp);
if( sqlite3MallocFailed() ){
return 0;
}
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;
#ifdef SQLITE_DEBUG
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==0 || 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==0 || p->magic==VDBE_MAGIC_INIT );
if( p && addr>=0 && p->nOp>addr && p->aOp ){
p->aOp[addr].p2 = 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){
sqlite3VdbeChangeP2(p, addr, p->nOp);
}
/*
** Delete a P3 value if necessary.
*/
static void freeP3(int p3type, void *p3){
if( p3 ){
switch( p3type ){
case P3_DYNAMIC:
case P3_KEYINFO:
case P3_KEYINFO_HANDOFF: {
sqliteFree(p3);
break;
}
case P3_VDBEFUNC: {
VdbeFunc *pVdbeFunc = (VdbeFunc *)p3;
sqlite3VdbeDeleteAuxData(pVdbeFunc, 0);
sqliteFree(pVdbeFunc);
break;
}
case P3_MEM: {
sqlite3ValueFree((sqlite3_value*)p3);
break;
}
}
}
}
/*
** Change N opcodes starting at addr to No-ops.
*/
void sqlite3VdbeChangeToNoop(Vdbe *p, int addr, int N){
VdbeOp *pOp = &p->aOp[addr];
while( N-- ){
freeP3(pOp->p3type, pOp->p3);
memset(pOp, 0, sizeof(pOp[0]));
pOp->opcode = OP_Noop;
pOp++;
}
}
/*
** 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_KEYINFO it means that zP3 is a pointer to a KeyInfo structure.
** A copy is made of the KeyInfo structure into memory obtained from
** sqliteMalloc, to be freed when the Vdbe is finalized.
** n==P3_KEYINFO_HANDOFF indicates that zP3 points to a KeyInfo structure
** stored in memory that the caller has obtained from sqliteMalloc. The
** caller should not free the allocation, it will be freed when the Vdbe is
** finalized.
**
** Other values of n (P3_STATIC, P3_COLLSEQ etc.) indicate that zP3 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 P3 on the most recently inserted instruction.
*/
void sqlite3VdbeChangeP3(Vdbe *p, int addr, const char *zP3, int n){
Op *pOp;
assert( p==0 || p->magic==VDBE_MAGIC_INIT );
if( p==0 || p->aOp==0 || sqlite3MallocFailed() ){
if (n != P3_KEYINFO) {
freeP3(n, (void*)*(char**)&zP3);
}
return;
}
if( addr<0 || addr>=p->nOp ){
addr = p->nOp - 1;
if( addr<0 ) return;
}
pOp = &p->aOp[addr];
freeP3(pOp->p3type, pOp->p3);
pOp->p3 = 0;
if( zP3==0 ){
pOp->p3 = 0;
pOp->p3type = P3_NOTUSED;
}else if( n==P3_KEYINFO ){
KeyInfo *pKeyInfo;
int nField, nByte;
nField = ((KeyInfo*)zP3)->nField;
nByte = sizeof(*pKeyInfo) + (nField-1)*sizeof(pKeyInfo->aColl[0]) + nField;
pKeyInfo = sqliteMallocRaw( nByte );
pOp->p3 = (char*)pKeyInfo;
if( pKeyInfo ){
unsigned char *aSortOrder;
memcpy(pKeyInfo, zP3, nByte);
aSortOrder = pKeyInfo->aSortOrder;
if( aSortOrder ){
pKeyInfo->aSortOrder = (unsigned char*)&pKeyInfo->aColl[nField];
memcpy(pKeyInfo->aSortOrder, aSortOrder, nField);
}
pOp->p3type = P3_KEYINFO;
}else{
pOp->p3type = P3_NOTUSED;
}
}else if( n==P3_KEYINFO_HANDOFF ){
pOp->p3 = (char*)zP3;
pOp->p3type = P3_KEYINFO;
}else if( n<0 ){
pOp->p3 = (char*)zP3;
pOp->p3type = n;
}else{
if( n==0 ) n = strlen(zP3);
pOp->p3 = sqliteStrNDup(zP3, n);
pOp->p3type = P3_DYNAMIC;
}
}
#ifndef NDEBUG
/*
** Replace the P3 field of the most recently coded instruction with
** comment text.
*/
void sqlite3VdbeComment(Vdbe *p, const char *zFormat, ...){
va_list ap;
assert( p->nOp>0 );
assert( p->aOp==0 || p->aOp[p->nOp-1].p3==0
|| sqlite3MallocFailed() );
va_start(ap, zFormat);
sqlite3VdbeChangeP3(p, -1, sqlite3VMPrintf(zFormat, ap), P3_DYNAMIC);
va_end(ap);
}
#endif
/*
** 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];
}
#if !defined(SQLITE_OMIT_EXPLAIN) || !defined(NDEBUG) \
|| defined(VDBE_PROFILE) || defined(SQLITE_DEBUG)
/*
** Compute a string that describes the P3 parameter for an opcode.
** Use zTemp for any required temporary buffer space.
*/
static char *displayP3(Op *pOp, char *zTemp, int nTemp){
char *zP3;
assert( nTemp>=20 );
switch( pOp->p3type ){
case P3_KEYINFO: {
int i, j;
KeyInfo *pKeyInfo = (KeyInfo*)pOp->p3;
sprintf(zTemp, "keyinfo(%d", pKeyInfo->nField);
i = strlen(zTemp);
for(j=0; j<pKeyInfo->nField; j++){
CollSeq *pColl = pKeyInfo->aColl[j];
if( pColl ){
int n = strlen(pColl->zName);
if( i+n>nTemp-6 ){
strcpy(&zTemp[i],",...");
break;
}
zTemp[i++] = ',';
if( pKeyInfo->aSortOrder && pKeyInfo->aSortOrder[j] ){
zTemp[i++] = '-';
}
strcpy(&zTemp[i], pColl->zName);
i += n;
}else if( i+4<nTemp-6 ){
strcpy(&zTemp[i],",nil");
i += 4;
}
}
zTemp[i++] = ')';
zTemp[i] = 0;
assert( i<nTemp );
zP3 = zTemp;
break;
}
case P3_COLLSEQ: {
CollSeq *pColl = (CollSeq*)pOp->p3;
sprintf(zTemp, "collseq(%.20s)", pColl->zName);
zP3 = zTemp;
break;
}
case P3_FUNCDEF: {
FuncDef *pDef = (FuncDef*)pOp->p3;
char zNum[30];
sprintf(zTemp, "%.*s", nTemp, pDef->zName);
sprintf(zNum,"(%d)", pDef->nArg);
if( strlen(zTemp)+strlen(zNum)+1<=nTemp ){
strcat(zTemp, zNum);
}
zP3 = zTemp;
break;
}
default: {
zP3 = pOp->p3;
if( zP3==0 || pOp->opcode==OP_Noop ){
zP3 = "";
}
}
}
return zP3;
}
#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 *zP3;
char zPtr[50];
static const char *zFormat1 = "%4d %-13s %4d %4d %s\n";
if( pOut==0 ) pOut = stdout;
zP3 = displayP3(pOp, zPtr, sizeof(zPtr));
fprintf(pOut, zFormat1,
pc, sqlite3OpcodeNames[pOp->opcode], pOp->p1, pOp->p2, zP3);
fflush(pOut);
}
#endif
/*
** Release an array of N Mem elements
*/
static void releaseMemArray(Mem *p, int N){
if( p ){
while( N-->0 ){
sqlite3VdbeMemRelease(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".
*/
int sqlite3VdbeList(
Vdbe *p /* The VDBE */
){
sqlite3 *db = p->db;
int i;
int rc = SQLITE_OK;
assert( p->explain );
if( p->magic!=VDBE_MAGIC_RUN ) return SQLITE_MISUSE;
assert( db->magic==SQLITE_MAGIC_BUSY );
assert( p->rc==SQLITE_OK || p->rc==SQLITE_BUSY );
/* Even though this opcode does not put dynamic strings onto the
** the stack, they may become dynamic if the user calls
** sqlite3_column_text16(), causing a translation to UTF-16 encoding.
*/
if( p->pTos==&p->aStack[4] ){
releaseMemArray(p->aStack, 5);
}
p->resOnStack = 0;
do{
i = p->pc++;
}while( i<p->nOp && p->explain==2 && p->aOp[i].opcode!=OP_Explain );
if( i>=p->nOp ){
p->rc = SQLITE_OK;
rc = SQLITE_DONE;
}else if( db->flags & SQLITE_Interrupt ){
db->flags &= ~SQLITE_Interrupt;
p->rc = SQLITE_INTERRUPT;
rc = SQLITE_ERROR;
sqlite3SetString(&p->zErrMsg, sqlite3ErrStr(p->rc), (char*)0);
}else{
Op *pOp = &p->aOp[i];
Mem *pMem = p->aStack;
pMem->flags = MEM_Int;
pMem->type = SQLITE_INTEGER;
pMem->i = i; /* Program counter */
pMem++;
pMem->flags = MEM_Static|MEM_Str|MEM_Term;
pMem->z = sqlite3OpcodeNames[pOp->opcode]; /* Opcode */
pMem->n = strlen(pMem->z);
pMem->type = SQLITE_TEXT;
pMem->enc = SQLITE_UTF8;
pMem++;
pMem->flags = MEM_Int;
pMem->i = pOp->p1; /* P1 */
pMem->type = SQLITE_INTEGER;
pMem++;
pMem->flags = MEM_Int;
pMem->i = pOp->p2; /* P2 */
pMem->type = SQLITE_INTEGER;
pMem++;
pMem->flags = MEM_Ephem|MEM_Str|MEM_Term; /* P3 */
pMem->z = displayP3(pOp, pMem->zShort, sizeof(pMem->zShort));
pMem->n = strlen(pMem->z);
pMem->type = SQLITE_TEXT;
pMem->enc = SQLITE_UTF8;
p->nResColumn = 5 - 2*(p->explain-1);
p->pTos = pMem;
p->rc = SQLITE_OK;
p->resOnStack = 1;
rc = SQLITE_ROW;
}
return rc;
}
#endif /* SQLITE_OMIT_EXPLAIN */
/*
** Print the SQL that was used to generate a VDBE program.
*/
void sqlite3VdbePrintSql(Vdbe *p){
#ifdef SQLITE_DEBUG
int nOp = p->nOp;
VdbeOp *pOp;
if( nOp<1 ) return;
pOp = &p->aOp[nOp-1];
if( pOp->opcode==OP_Noop && pOp->p3!=0 ){
const char *z = pOp->p3;
while( isspace(*(u8*)z) ) z++;
printf("SQL: [%s]\n", z);
}
#endif
}
/*
** Prepare a virtual machine for execution. This involves things such
** as allocating stack space and initializing the program counter.
** After the VDBE has be prepped, it can be executed by one or more
** calls to sqlite3VdbeExec().
**
** This is the only way to move a VDBE from VDBE_MAGIC_INIT to
** VDBE_MAGIC_RUN.
*/
void sqlite3VdbeMakeReady(
Vdbe *p, /* The VDBE */
int nVar, /* Number of '?' see in the SQL statement */
int nMem, /* Number of memory cells to allocate */
int nCursor, /* Number of cursors to allocate */
int isExplain /* True if the EXPLAIN keywords is present */
){
int n;
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. This
* is because the call to resizeOpArray() below may shrink the
* p->aOp[] array to save memory if called when in VDBE_MAGIC_RUN
* state.
*/
p->magic = VDBE_MAGIC_RUN;
/* 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. (Added later:) The
** resolveP2Values() call computes a tighter upper bound on the
** stack size.
**
** Allocation all the stack space we will ever need.
*/
if( p->aStack==0 ){
int nArg; /* Maximum number of args passed to a user function. */
int nStack; /* Maximum number of stack entries required */
resolveP2Values(p, &nArg, &nStack);
resizeOpArray(p, p->nOp);
assert( nVar>=0 );
assert( nStack<p->nOp );
nStack = isExplain ? 10 : nStack;
p->aStack = sqliteMalloc(
nStack*sizeof(p->aStack[0]) /* aStack */
+ nArg*sizeof(Mem*) /* apArg */
+ nVar*sizeof(Mem) /* aVar */
+ nVar*sizeof(char*) /* azVar */
+ nMem*sizeof(Mem) /* aMem */
+ nCursor*sizeof(Cursor*) /* apCsr */
);
if( !sqlite3MallocFailed() ){
p->aMem = &p->aStack[nStack];
p->nMem = nMem;
p->aVar = &p->aMem[nMem];
p->nVar = nVar;
p->okVar = 0;
p->apArg = (Mem**)&p->aVar[nVar];
p->azVar = (char**)&p->apArg[nArg];
p->apCsr = (Cursor**)&p->azVar[nVar];
p->nCursor = nCursor;
for(n=0; n<nVar; n++){
p->aVar[n].flags = MEM_Null;
}
}
}
for(n=0; n<p->nMem; n++){
p->aMem[n].flags = MEM_Null;
}
#ifdef SQLITE_DEBUG
if( (p->db->flags & SQLITE_VdbeListing)!=0
|| sqlite3OsFileExists("vdbe_explain")
){
int i;
printf("VDBE Program Listing:\n");
sqlite3VdbePrintSql(p);
for(i=0; i<p->nOp; i++){
sqlite3VdbePrintOp(stdout, i, &p->aOp[i]);
}
}
if( sqlite3OsFileExists("vdbe_trace") ){
p->trace = stdout;
}
#endif
p->pTos = &p->aStack[-1];
p->pc = -1;
p->rc = SQLITE_OK;
p->uniqueCnt = 0;
p->returnDepth = 0;
p->errorAction = OE_Abort;
p->popStack = 0;
p->explain |= isExplain;
p->magic = VDBE_MAGIC_RUN;
p->nChange = 0;
p->cacheCtr = 1;
p->minWriteFileFormat = 255;
#ifdef VDBE_PROFILE
{
int i;
for(i=0; i<p->nOp; i++){
p->aOp[i].cnt = 0;
p->aOp[i].cycles = 0;
}
}
#endif
}
/*
** Close a cursor and release all the resources that cursor happens
** to hold.
*/
void sqlite3VdbeFreeCursor(Cursor *pCx){
if( pCx==0 ){
return;
}
if( pCx->pCursor ){
sqlite3BtreeCloseCursor(pCx->pCursor);
}
if( pCx->pBt ){
sqlite3BtreeClose(pCx->pBt);
}
sqliteFree(pCx->pData);
sqliteFree(pCx->aType);
sqliteFree(pCx);
}
/*
** Close all cursors
*/
static void closeAllCursors(Vdbe *p){
int i;
if( p->apCsr==0 ) return;
for(i=0; i<p->nCursor; i++){
sqlite3VdbeFreeCursor(p->apCsr[i]);
p->apCsr[i] = 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 ){
releaseMemArray(p->aStack, 1 + (p->pTos - p->aStack));
p->pTos = &p->aStack[-1];
}
closeAllCursors(p);
releaseMemArray(p->aMem, p->nMem);
sqlite3VdbeFifoClear(&p->sFifo);
if( p->contextStack ){
for(i=0; i<p->contextStackTop; i++){
sqlite3VdbeFifoClear(&p->contextStack[i].sFifo);
}
sqliteFree(p->contextStack);
}
p->contextStack = 0;
p->contextStackDepth = 0;
p->contextStackTop = 0;
sqliteFree(p->zErrMsg);
p->zErrMsg = 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;
releaseMemArray(p->aColName, p->nResColumn*COLNAME_N);
sqliteFree(p->aColName);
n = nResColumn*COLNAME_N;
p->nResColumn = nResColumn;
p->aColName = pColName = (Mem*)sqliteMalloc( sizeof(Mem)*n );
if( p->aColName==0 ) return;
while( n-- > 0 ){
(pColName++)->flags = MEM_Null;
}
}
/*
** 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().
**
** If N==P3_STATIC it means that zName is a pointer to a constant static
** string and we can just copy the pointer. If it is P3_DYNAMIC, then
** the string is freed using sqliteFree() when the vdbe is finished with
** it. Otherwise, N bytes of zName are copied.
*/
int sqlite3VdbeSetColName(Vdbe *p, int idx, int var, const char *zName, int N){
int rc;
Mem *pColName;
assert( idx<p->nResColumn );
assert( var<COLNAME_N );
if( sqlite3MallocFailed() ) return SQLITE_NOMEM;
assert( p->aColName!=0 );
pColName = &(p->aColName[idx+var*p->nResColumn]);
if( N==P3_DYNAMIC || N==P3_STATIC ){
rc = sqlite3VdbeMemSetStr(pColName, zName, -1, SQLITE_UTF8, SQLITE_STATIC);
}else{
rc = sqlite3VdbeMemSetStr(pColName, zName, N, SQLITE_UTF8,SQLITE_TRANSIENT);
}
if( rc==SQLITE_OK && N==P3_DYNAMIC ){
pColName->flags = (pColName->flags&(~MEM_Static))|MEM_Dyn;
pColName->xDel = 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){
int i;
int nTrans = 0; /* Number of databases with an active write-transaction */
int rc = SQLITE_OK;
int needXcommit = 0;
for(i=0; i<db->nDb; i++){
Btree *pBt = db->aDb[i].pBt;
if( pBt && sqlite3BtreeIsInTrans(pBt) ){
needXcommit = 1;
if( i!=1 ) nTrans++;
}
}
/* If there are any write-transactions at all, invoke the commit hook */
if( needXcommit && db->xCommitCallback ){
sqlite3SafetyOff(db);
rc = db->xCommitCallback(db->pCommitArg);
sqlite3SafetyOn(db);
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:. In that case we do
** not support atomic multi-file commits, so use the simple case then
** too.
*/
if( 0==strlen(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 = sqlite3BtreeSync(pBt, 0);
}
}
/* Do the commit only if all databases successfully synced */
if( rc==SQLITE_OK ){
for(i=0; i<db->nDb; i++){
Btree *pBt = db->aDb[i].pBt;
if( pBt ){
sqlite3BtreeCommit(pBt);
}
}
}
}
/* 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{
int needSync = 0;
char *zMaster = 0; /* File-name for the master journal */
char const *zMainFile = sqlite3BtreeGetFilename(db->aDb[0].pBt);
OsFile *master = 0;
/* Select a master journal file name */
do {
u32 random;
sqliteFree(zMaster);
sqlite3Randomness(sizeof(random), &random);
zMaster = sqlite3MPrintf("%s-mj%08X", zMainFile, random&0x7fffffff);
if( !zMaster ){
return SQLITE_NOMEM;
}
}while( sqlite3OsFileExists(zMaster) );
/* Open the master journal. */
rc = sqlite3OsOpenExclusive(zMaster, &master, 0);
if( rc!=SQLITE_OK ){
sqliteFree(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( i==1 ) continue; /* Ignore the TEMP database */
if( pBt && sqlite3BtreeIsInTrans(pBt) ){
char const *zFile = sqlite3BtreeGetJournalname(pBt);
if( zFile[0]==0 ) continue; /* Ignore :memory: databases */
if( !needSync && !sqlite3BtreeSyncDisabled(pBt) ){
needSync = 1;
}
rc = sqlite3OsWrite(master, zFile, strlen(zFile)+1);
if( rc!=SQLITE_OK ){
sqlite3OsClose(&master);
sqlite3OsDelete(zMaster);
sqliteFree(zMaster);
return rc;
}
}
}
/* Sync the master journal file. Before doing this, open the directory
** the master journal file is store in so that it gets synced too.
*/
zMainFile = sqlite3BtreeGetDirname(db->aDb[0].pBt);
rc = sqlite3OsOpenDirectory(master, zMainFile);
if( rc!=SQLITE_OK ||
(needSync && (rc=sqlite3OsSync(master,0))!=SQLITE_OK) ){
sqlite3OsClose(&master);
sqlite3OsDelete(zMaster);
sqliteFree(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 sqlite3BtreeSync(),
** 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
** occured.
*/
for(i=0; i<db->nDb; i++){
Btree *pBt = db->aDb[i].pBt;
if( pBt && sqlite3BtreeIsInTrans(pBt) ){
rc = sqlite3BtreeSync(pBt, zMaster);
if( rc!=SQLITE_OK ){
sqlite3OsClose(&master);
sqliteFree(zMaster);
return rc;
}
}
}
sqlite3OsClose(&master);
/* 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(zMaster);
assert( rc==SQLITE_OK );
sqliteFree(zMaster);
zMaster = 0;
rc = sqlite3OsSyncDirectory(zMainFile);
if( rc!=SQLITE_OK ){
/* This is not good. The master journal file has been deleted, but
** the directory sync failed. There is no completely safe course of
** action from here. The individual journals contain the name of the
** master journal file, but there is no way of knowing if that
** master journal exists now or if it will exist after the operating
** system crash that may follow the fsync() failure.
*/
return rc;
}
/* All files and directories have already been synced, so the following
** calls to sqlite3BtreeCommit() are only closing files and deleting
** 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.
*/
for(i=0; i<db->nDb; i++){
Btree *pBt = db->aDb[i].pBt;
if( pBt ){
sqlite3BtreeCommit(pBt);
}
}
}
#endif
return rc;
}
/*
** Find every active VM other than pVdbe and change its status to
** aborted. This happens when one VM causes a rollback due to an
** ON CONFLICT ROLLBACK clause (for example). The other VMs must be
** aborted so that they do not have data rolled out from underneath
** them leading to a segfault.
*/
void sqlite3AbortOtherActiveVdbes(sqlite3 *db, Vdbe *pExcept){
Vdbe *pOther;
for(pOther=db->pVdbe; pOther; pOther=pOther->pNext){
if( pOther==pExcept ) continue;
if( pOther->magic!=VDBE_MAGIC_RUN || pOther->pc<0 ) continue;
closeAllCursors(pOther);
pOther->aborted = 1;
}
}
/*
** 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;
p = db->pVdbe;
while( p ){
if( p->magic==VDBE_MAGIC_RUN && p->pc>=0 ){
cnt++;
}
p = p->pNext;
}
assert( cnt==db->activeVdbeCnt );
}
#else
#define checkActiveVdbeCnt(x)
#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.
**
** 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){
sqlite3 *db = p->db;
int i;
int (*xFunc)(Btree *pBt) = 0; /* Function to call on each btree backend */
int isSpecialError; /* Set to true if SQLITE_NOMEM or IOERR */
/* 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.
**
** Special errors:
**
** If an SQLITE_NOMEM error has occured in a statement that writes to
** the database, then either a statement or transaction must be rolled
** back to ensure the tree-structures are in a consistent state. A
** statement transaction is rolled back if one is open, otherwise the
** entire transaction must be rolled back.
**
** If an SQLITE_IOERR error has occured in a statement that writes to
** the database, then the entire transaction must be rolled back. The
** I/O error may have caused garbage to be written to the journal
** file. Were the transaction to continue and eventually be rolled
** back that garbage might end up in the database file.
**
** In both of the above cases, the Vdbe.errorAction variable is
** ignored. If the sqlite3.autoCommit flag is false and a transaction
** is rolled back, it will be set to true.
**
** Other errors:
**
** No error:
**
*/
if( sqlite3MallocFailed() ){
p->rc = SQLITE_NOMEM;
}
if( p->magic!=VDBE_MAGIC_RUN ){
/* Already halted. Nothing to do. */
assert( p->magic==VDBE_MAGIC_HALT );
return SQLITE_OK;
}
closeAllCursors(p);
checkActiveVdbeCnt(db);
/* No commit or rollback needed if the program never started */
if( p->pc>=0 ){
/* Check for one of the special errors - SQLITE_NOMEM or SQLITE_IOERR */
isSpecialError = ((p->rc==SQLITE_NOMEM || p->rc==SQLITE_IOERR)?1:0);
if( isSpecialError ){
/* This loop does static analysis of the query to see which of the
** following three categories it falls into:
**
** Read-only
** Query with statement journal
** Query without statement journal
**
** We could do something more elegant than this static analysis (i.e.
** store the type of query as part of the compliation phase), but
** handling malloc() or IO failure is a fairly obscure edge case so
** this is probably easier. Todo: Might be an opportunity to reduce
** code size a very small amount though...
*/
int isReadOnly = 1;
int isStatement = 0;
assert(p->aOp || p->nOp==0);
for(i=0; i<p->nOp; i++){
switch( p->aOp[i].opcode ){
case OP_Transaction:
isReadOnly = 0;
break;
case OP_Statement:
isStatement = 1;
break;
}
}
/* If the query was read-only, we need do no rollback at all. Otherwise,
** proceed with the special handling.
*/
if( !isReadOnly ){
if( p->rc==SQLITE_NOMEM && isStatement ){
xFunc = sqlite3BtreeRollbackStmt;
}else{
/* We are forced to roll back the active transaction. Before doing
** so, abort any other statements this handle currently has active.
*/
sqlite3AbortOtherActiveVdbes(db, p);
sqlite3RollbackAll(db);
db->autoCommit = 1;
}
}
}
/* If the auto-commit flag is set and this is the only active vdbe, 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 occured.
*/
if( db->autoCommit && db->activeVdbeCnt==1 ){
if( p->rc==SQLITE_OK || (p->errorAction==OE_Fail && !isSpecialError) ){
/* The auto-commit flag is true, and the vdbe program was
** successful or hit an 'OR FAIL' constraint. This means a commit
** is required.
*/
int rc = vdbeCommit(db);
if( rc==SQLITE_BUSY ){
return SQLITE_BUSY;
}else if( rc!=SQLITE_OK ){
p->rc = rc;
sqlite3RollbackAll(db);
}else{
sqlite3CommitInternalChanges(db);
}
}else{
sqlite3RollbackAll(db);
}
}else if( !xFunc ){
if( p->rc==SQLITE_OK || p->errorAction==OE_Fail ){
xFunc = sqlite3BtreeCommitStmt;
}else if( p->errorAction==OE_Abort ){
xFunc = sqlite3BtreeRollbackStmt;
}else{
sqlite3AbortOtherActiveVdbes(db, p);
sqlite3RollbackAll(db);
db->autoCommit = 1;
}
}
/* If xFunc is not NULL, then it is one of sqlite3BtreeRollbackStmt or
** sqlite3BtreeCommitStmt. Call it once on each backend. If an error occurs
** and the return code is still SQLITE_OK, set the return code to the new
** error value.
*/
assert(!xFunc ||
xFunc==sqlite3BtreeCommitStmt ||
xFunc==sqlite3BtreeRollbackStmt
);
for(i=0; xFunc && i<db->nDb; i++){
int rc;
Btree *pBt = db->aDb[i].pBt;
if( pBt ){
rc = xFunc(pBt);
if( rc && (p->rc==SQLITE_OK || p->rc==SQLITE_CONSTRAINT) ){
p->rc = rc;
sqlite3SetString(&p->zErrMsg, 0);
}
}
}
/* If this was an INSERT, UPDATE or DELETE and the statement was committed,
** set the change counter.
*/
if( p->changeCntOn && p->pc>=0 ){
if( !xFunc || xFunc==sqlite3BtreeCommitStmt ){
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, 0);
db->flags = (db->flags | SQLITE_InternChanges);
}
}
/* We have successfully halted and closed the VM. Record this fact. */
if( p->pc>=0 ){
db->activeVdbeCnt--;
}
p->magic = VDBE_MAGIC_HALT;
checkActiveVdbeCnt(db);
return SQLITE_OK;
}
/*
** Clean up a VDBE after execution but do not delete the VDBE just yet.
** Write any error messages into *pzErrMsg. Return the result code.
**
** After this routine is run, the VDBE should be ready to be executed
** again.
**
** To look at it another way, this routine resets the state of the
** virtual machine from VDBE_MAGIC_RUN or VDBE_MAGIC_HALT back to
** VDBE_MAGIC_INIT.
*/
int sqlite3VdbeReset(Vdbe *p){
if( p->magic!=VDBE_MAGIC_RUN && p->magic!=VDBE_MAGIC_HALT ){
sqlite3Error(p->db, SQLITE_MISUSE, 0);
return SQLITE_MISUSE;
}
/* If the VM did not run to completion or if it encountered an
** error, then it might not have been halted properly. So halt
** it now.
*/
sqlite3VdbeHalt(p);
/* If the VDBE has be run even partially, then transfer the error code
** and error message from the VDBE into the main database structure. But
** if the VDBE has just been set to run but has not actually executed any
** instructions yet, leave the main database error information unchanged.
*/
if( p->pc>=0 ){
if( p->zErrMsg ){
sqlite3* db = p->db;
sqlite3ValueSetStr(db->pErr, -1, p->zErrMsg, SQLITE_UTF8, sqlite3FreeX);
db->errCode = p->rc;
p->zErrMsg = 0;
}else if( p->rc ){
sqlite3Error(p->db, p->rc, 0);
}else{
sqlite3Error(p->db, SQLITE_OK, 0);
}
}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(p->db, p->rc, 0);
}
/* Reclaim all memory used by the VDBE
*/
Cleanup(p);
/* Save profiling information from this VDBE run.
*/
assert( p->pTos<&p->aStack[p->pc<0?0:p->pc] || !p->aStack );
#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;
p->aborted = 0;
if( p->rc==SQLITE_SCHEMA ){
sqlite3ResetInternalSchema(p->db, 0);
}
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){
int rc = SQLITE_OK;
if( p->magic==VDBE_MAGIC_RUN || p->magic==VDBE_MAGIC_HALT ){
rc = sqlite3VdbeReset(p);
}else if( p->magic!=VDBE_MAGIC_INIT ){
return SQLITE_MISUSE;
}
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&(1<<i))) && pAux->pAux ){
if( pAux->xDelete ){
pAux->xDelete(pAux->pAux);
}
pAux->pAux = 0;
}
}
}
/*
** 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;
}
if( p->aOp ){
for(i=0; i<p->nOp; i++){
Op *pOp = &p->aOp[i];
freeP3(pOp->p3type, pOp->p3);
}
sqliteFree(p->aOp);
}
releaseMemArray(p->aVar, p->nVar);
sqliteFree(p->aLabel);
sqliteFree(p->aStack);
releaseMemArray(p->aColName, p->nResColumn*COLNAME_N);
sqliteFree(p->aColName);
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, rc;
extern int sqlite3_search_count;
assert( p->isTable );
if( p->isTable ){
rc = sqlite3BtreeMoveto(p->pCursor, 0, p->movetoTarget, &res);
}else{
rc = sqlite3BtreeMoveto(p->pCursor,(char*)&p->movetoTarget,
sizeof(i64),&res);
}
if( rc ) return rc;
*p->pIncrKey = 0;
p->lastRowid = keyToInt(p->movetoTarget);
p->rowidIsValid = res==0;
if( res<0 ){
rc = sqlite3BtreeNext(p->pCursor, &res);
if( rc ) return rc;
}
sqlite3_search_count++;
p->deferredMoveto = 0;
p->cacheStatus = CACHE_STALE;
}
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 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;
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)0x00001000)<<32)-1)
i64 i = pMem->i;
u64 u;
if( file_format>=4 && (i&1)==i ){
return 8+i;
}
u = i<0 ? -i : 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;
}
if( flags&MEM_Str ){
int n = pMem->n;
assert( n>=0 );
return ((n*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(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];
}
}
/*
** 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, Mem *pMem, int file_format){
u32 serial_type = sqlite3VdbeSerialType(pMem, file_format);
int len;
/* Integer and Real */
if( serial_type<=7 && serial_type>0 ){
u64 v;
int i;
if( serial_type==7 ){
v = *(u64*)&pMem->r;
}else{
v = *(u64*)&pMem->i;
}
len = i = sqlite3VdbeSerialTypeLen(serial_type);
while( i-- ){
buf[i] = (v&0xFF);
v >>= 8;
}
return len;
}
/* String or blob */
if( serial_type>=12 ){
len = sqlite3VdbeSerialTypeLen(serial_type);
memcpy(buf, pMem->z, len);
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.
*/
int 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->i = (signed char)buf[0];
pMem->flags = MEM_Int;
return 1;
}
case 2: { /* 2-byte signed integer */
pMem->i = (((signed char)buf[0])<<8) | buf[1];
pMem->flags = MEM_Int;
return 2;
}
case 3: { /* 3-byte signed integer */
pMem->i = (((signed char)buf[0])<<16) | (buf[1]<<8) | buf[2];
pMem->flags = MEM_Int;
return 3;
}
case 4: { /* 4-byte signed integer */
pMem->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->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. The byte order differs on some (broken) architectures.
*/
static const u64 t1 = ((u64)0x3ff00000)<<32;
assert( 1.0==*(double*)&t1 );
#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->i = *(i64*)&x;
pMem->flags = MEM_Int;
}else{
pMem->r = *(double*)&x;
pMem->flags = MEM_Real;
}
return 8;
}
case 8: /* Integer 0 */
case 9: { /* Integer 1 */
pMem->i = serial_type-8;
pMem->flags = MEM_Int;
return 0;
}
default: {
int 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;
}
/*
** The header of a record consists of a sequence variable-length integers.
** These integers are almost always small and are encoded as a single byte.
** The following macro takes advantage this fact to provide a fast decode
** of the integers in a record header. It is faster for the common case
** where the integer is a single byte. It is a little slower when the
** integer is two or more bytes. But overall it is faster.
**
** The following expressions are equivalent:
**
** x = sqlite3GetVarint32( A, &B );
**
** x = GetVarint( A, B );
**
*/
#define GetVarint(A,B) ((B = *(A))<=0x7f ? 1 : sqlite3GetVarint32(A, &B))
/*
** This function compares the two table rows or index 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}. Both Key1 and Key2 must be byte strings
** composed by the OP_MakeRecord opcode of the VDBE.
*/
int sqlite3VdbeRecordCompare(
void *userData,
int nKey1, const void *pKey1,
int nKey2, const void *pKey2
){
KeyInfo *pKeyInfo = (KeyInfo*)userData;
u32 d1, d2; /* Offset into aKey[] of next data element */
u32 idx1, idx2; /* Offset into aKey[] of next header element */
u32 szHdr1, szHdr2; /* Number of bytes in header */
int i = 0;
int nField;
int rc = 0;
const unsigned char *aKey1 = (const unsigned char *)pKey1;
const unsigned char *aKey2 = (const unsigned char *)pKey2;
Mem mem1;
Mem mem2;
mem1.enc = pKeyInfo->enc;
mem2.enc = pKeyInfo->enc;
idx1 = GetVarint(aKey1, szHdr1);
d1 = szHdr1;
idx2 = GetVarint(aKey2, szHdr2);
d2 = szHdr2;
nField = pKeyInfo->nField;
while( idx1<szHdr1 && idx2<szHdr2 ){
u32 serial_type1;
u32 serial_type2;
/* Read the serial types for the next element in each key. */
idx1 += GetVarint( aKey1+idx1, serial_type1 );
if( d1>=nKey1 && sqlite3VdbeSerialTypeLen(serial_type1)>0 ) break;
idx2 += GetVarint( aKey2+idx2, serial_type2 );
if( d2>=nKey2 && sqlite3VdbeSerialTypeLen(serial_type2)>0 ) break;
/* 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.
*/
d1 += sqlite3VdbeSerialGet(&aKey1[d1], serial_type1, &mem1);
d2 += sqlite3VdbeSerialGet(&aKey2[d2], serial_type2, &mem2);
rc = sqlite3MemCompare(&mem1, &mem2, i<nField ? pKeyInfo->aColl[i] : 0);
if( mem1.flags & MEM_Dyn ) sqlite3VdbeMemRelease(&mem1);
if( mem2.flags & MEM_Dyn ) sqlite3VdbeMemRelease(&mem2);
if( rc!=0 ){
break;
}
i++;
}
/* 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( rc==0 ){
if( pKeyInfo->incrKey ){
rc = -1;
}else if( d1<nKey1 ){
rc = 1;
}else if( d2<nKey2 ){
rc = -1;
}
}else if( pKeyInfo->aSortOrder && i<pKeyInfo->nField
&& pKeyInfo->aSortOrder[i] ){
rc = -rc;
}
return rc;
}
/*
** The argument is an index entry composed using the OP_MakeRecord opcode.
** The last entry in this record should be an integer (specifically
** an integer rowid). This routine returns the number of bytes in
** that integer.
*/
int sqlite3VdbeIdxRowidLen(const u8 *aKey){
u32 szHdr; /* Size of the header */
u32 typeRowid; /* Serial type of the rowid */
sqlite3GetVarint32(aKey, &szHdr);
sqlite3GetVarint32(&aKey[szHdr-1], &typeRowid);
return sqlite3VdbeSerialTypeLen(typeRowid);
}
/*
** 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.
*/
int sqlite3VdbeIdxRowid(BtCursor *pCur, i64 *rowid){
i64 nCellKey;
int rc;
u32 szHdr; /* Size of the header */
u32 typeRowid; /* Serial type of the rowid */
u32 lenRowid; /* Size of the rowid */
Mem m, v;
sqlite3BtreeKeySize(pCur, &nCellKey);
if( nCellKey<=0 ){
return SQLITE_CORRUPT_BKPT;
}
rc = sqlite3VdbeMemFromBtree(pCur, 0, nCellKey, 1, &m);
if( rc ){
return rc;
}
sqlite3GetVarint32((u8*)m.z, &szHdr);
sqlite3GetVarint32((u8*)&m.z[szHdr-1], &typeRowid);
lenRowid = sqlite3VdbeSerialTypeLen(typeRowid);
sqlite3VdbeSerialGet((u8*)&m.z[m.n-lenRowid], typeRowid, &v);
*rowid = v.i;
sqlite3VdbeMemRelease(&m);
return SQLITE_OK;
}
/*
** Compare the key of the 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.
**
** pKey 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.
*/
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 */
){
i64 nCellKey;
int rc;
BtCursor *pCur = pC->pCursor;
int lenRowid;
Mem m;
sqlite3BtreeKeySize(pCur, &nCellKey);
if( nCellKey<=0 ){
*res = 0;
return SQLITE_OK;
}
rc = sqlite3VdbeMemFromBtree(pC->pCursor, 0, nCellKey, 1, &m);
if( rc ){
return rc;
}
lenRowid = sqlite3VdbeIdxRowidLen((u8*)m.z);
*res = sqlite3VdbeRecordCompare(pC->pKeyInfo, m.n-lenRowid, m.z, nKey, pKey);
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){
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;
}
Reference in New Issue View Git Blame Copy Permalink