数据库系统

开发平台：

C/C++

vdbe.c.svn-base：源码内容

/*
** 2001 September 15
**
** 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.
**
*************************************************************************
** The code in this file implements execution method of the
** Virtual Database Engine (VDBE). A separate file ("vdbeaux.c")
** handles housekeeping details such as creating and deleting
** VDBE instances. This file is solely interested in executing
** the VDBE program.
**
** In the external interface, an "sqlite3_stmt*" is an opaque pointer
** to a VDBE.
**
** The SQL parser generates a program which is then executed by
** the VDBE to do the work of the SQL statement. VDBE programs are
** similar in form to assembly language. The program consists of
** a linear sequence of operations. Each operation has an opcode
** and 5 operands. Operands P1, P2, and P3 are integers. Operand P4
** is a null-terminated string. Operand P5 is an unsigned character.
** Few opcodes use all 5 operands.
**
** Computation results are stored on a set of registers numbered beginning
** with 1 and going up to Vdbe.nMem. Each register can store
** either an integer, a null-terminated string, a floating point
** number, or the SQL "NULL" value. An inplicit conversion from one
** type to the other occurs as necessary.
**
** Most of the code in this file is taken up by the sqlite3VdbeExec()
** function which does the work of interpreting a VDBE program.
** But other routines are also provided to help in building up
** a program instruction by instruction.
**
** Various scripts scan this source file in order to generate HTML
** documentation, headers files, or other derived files. The formatting
** of the code in this file is, therefore, important. See other comments
** in this file for details. If in doubt, do not deviate from existing
** commenting and indentation practices when changing or adding code.
**
** $Id: vdbe.c,v 1.730 2008/04/15 12:14:22 drh Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>
#include "vdbeInt.h"
/*
** The following global variable is incremented every time a cursor
** moves, either by the OP_MoveXX, OP_Next, or OP_Prev opcodes. The test
** procedures use this information to make sure that indices are
** working correctly. This variable has no function other than to
** help verify the correct operation of the library.
*/
#ifdef SQLITE_TEST
int sqlite3_search_count = 0;
#endif
/*
** When this global variable is positive, it gets decremented once before
** each instruction in the VDBE. When reaches zero, the u1.isInterrupted
** field of the sqlite3 structure is set in order to simulate and interrupt.
**
** This facility is used for testing purposes only. It does not function
** in an ordinary build.
*/
#ifdef SQLITE_TEST
int sqlite3_interrupt_count = 0;
#endif
/*
** The next global variable is incremented each type the OP_Sort opcode
** is executed. The test procedures use this information to make sure that
** sorting is occurring or not occuring at appropriate times. This variable
** has no function other than to help verify the correct operation of the
** library.
*/
#ifdef SQLITE_TEST
int sqlite3_sort_count = 0;
#endif
/*
** The next global variable records the size of the largest MEM_Blob
** or MEM_Str that has been used by a VDBE opcode. The test procedures
** use this information to make sure that the zero-blob functionality
** is working correctly. This variable has no function other than to
** help verify the correct operation of the library.
*/
#ifdef SQLITE_TEST
int sqlite3_max_blobsize = 0;
static void updateMaxBlobsize(Mem *p){
if( (p->flags & (MEM_Str|MEM_Blob))!=0 && p->n>sqlite3_max_blobsize ){
sqlite3_max_blobsize = p->n;
}
}
#endif
/*
** Test a register to see if it exceeds the current maximum blob size.
** If it does, record the new maximum blob size.
*/
#if defined(SQLITE_TEST) && !defined(SQLITE_OMIT_BUILTIN_TEST)
# define UPDATE_MAX_BLOBSIZE(P) updateMaxBlobsize(P)
#else
# define UPDATE_MAX_BLOBSIZE(P)
#endif
/*
** Release the memory associated with a register. This
** leaves the Mem.flags field in an inconsistent state.
*/
#define Release(P) if((P)->flags&MEM_Dyn){ sqlite3VdbeMemRelease(P); }
/*
** Convert the given register into a string if it isn't one
** already. Return non-zero if a malloc() fails.
*/
#define Stringify(P, enc)
if(((P)->flags&(MEM_Str|MEM_Blob))==0 && sqlite3VdbeMemStringify(P,enc))
{ goto no_mem; }
/*
** 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))
/*
** An ephemeral string value (signified by the MEM_Ephem flag) contains
** a pointer to a dynamically allocated string where some other entity
** is responsible for deallocating that string. Because the register
** does not control the string, it might be deleted without the register
** knowing it.
**
** This routine converts an ephemeral string into a dynamically allocated
** string that the register itself controls. In other words, it
** converts an MEM_Ephem string into an MEM_Dyn string.
*/
#define Deephemeralize(P)
if( ((P)->flags&MEM_Ephem)!=0
&& sqlite3VdbeMemMakeWriteable(P) ){ goto no_mem;}
/*
** Call sqlite3VdbeMemExpandBlob() on the supplied value (type Mem*)
** P if required.
*/
#define ExpandBlob(P) (((P)->flags&MEM_Zero)?sqlite3VdbeMemExpandBlob(P):0)
/*
** Argument pMem points at a regiser that will be passed to a
** user-defined function or returned to the user as the result of a query.
** The second argument, 'db_enc' is the text encoding used by the vdbe for
** register variables. This routine sets the pMem->enc and pMem->type
** variables used by the sqlite3_value_*() routines.
*/
#define storeTypeInfo(A,B) _storeTypeInfo(A)
static void _storeTypeInfo(Mem *pMem){
int flags = pMem->flags;
if( flags & MEM_Null ){
pMem->type = SQLITE_NULL;
}
else if( flags & MEM_Int ){
pMem->type = SQLITE_INTEGER;
}
else if( flags & MEM_Real ){
pMem->type = SQLITE_FLOAT;
}
else if( flags & MEM_Str ){
pMem->type = SQLITE_TEXT;
}else{
pMem->type = SQLITE_BLOB;
}
}
/*
** Properties of opcodes. The OPFLG_INITIALIZER macro is
** created by mkopcodeh.awk during compilation. Data is obtained
** from the comments following the "case OP_xxxx:" statements in
** this file.
*/
static unsigned char opcodeProperty[] = OPFLG_INITIALIZER;
/*
** Return true if an opcode has any of the OPFLG_xxx properties
** specified by mask.
*/
int sqlite3VdbeOpcodeHasProperty(int opcode, int mask){
assert( opcode>0 && opcode<sizeof(opcodeProperty) );
return (opcodeProperty[opcode]&mask)!=0;
}
/*
** Allocate cursor number iCur. Return a pointer to it. Return NULL
** if we run out of memory.
*/
static Cursor *allocateCursor(
Vdbe *p,
int iCur,
Op *pOp,
int iDb,
int isBtreeCursor
){
/* Find the memory cell that will be used to store the blob of memory
** required for this Cursor structure. It is convenient to use a
** vdbe memory cell to manage the memory allocation required for a
** Cursor structure for the following reasons:
**
** * Sometimes cursor numbers are used for a couple of different
** purposes in a vdbe program. The different uses might require
** different sized allocations. Memory cells provide growable
** allocations.
**
** * When using ENABLE_MEMORY_MANAGEMENT, memory cell buffers can
** be freed lazily via the sqlite3_release_memory() API. This
** minimizes the number of malloc calls made by the system.
**
** Memory cells for cursors are allocated at the top of the address
** space. Memory cell (p->nMem) corresponds to cursor 0. Space for
** cursor 1 is managed by memory cell (p->nMem-1), etc.
*/
Mem *pMem = &p->aMem[p->nMem-iCur];
int nByte;
Cursor *pCx = 0;
/* If the opcode of pOp is OP_SetNumColumns, then pOp->p2 contains
** the number of fields in the records contained in the table or
** index being opened. Use this to reserve space for the
** Cursor.aType[] array.
*/
int nField = 0;
if( pOp->opcode==OP_SetNumColumns || pOp->opcode==OP_OpenEphemeral ){
nField = pOp->p2;
}
nByte =
sizeof(Cursor) +
(isBtreeCursor?sqlite3BtreeCursorSize():0) +
2*nField*sizeof(u32);
assert( iCur<p->nCursor );
if( p->apCsr[iCur] ){
sqlite3VdbeFreeCursor(p, p->apCsr[iCur]);
p->apCsr[iCur] = 0;
}
if( SQLITE_OK==sqlite3VdbeMemGrow(pMem, nByte, 0) ){
p->apCsr[iCur] = pCx = (Cursor *)pMem->z;
memset(pMem->z, 0, nByte);
pCx->iDb = iDb;
pCx->nField = nField;
if( nField ){
pCx->aType = (u32 *)&pMem->z[sizeof(Cursor)];
}
if( isBtreeCursor ){
pCx->pCursor = (BtCursor *)&pMem->z[sizeof(Cursor)+2*nField*sizeof(u32)];
}
}
return pCx;
}
/*
** Try to convert a value into a numeric representation if we can
** do so without loss of information. In other words, if the string
** looks like a number, convert it into a number. If it does not
** look like a number, leave it alone.
*/
static void applyNumericAffinity(Mem *pRec){
if( (pRec->flags & (MEM_Real|MEM_Int))==0 ){
int realnum;
sqlite3VdbeMemNulTerminate(pRec);
if( (pRec->flags&MEM_Str)
&& sqlite3IsNumber(pRec->z, &realnum, pRec->enc) ){
i64 value;
sqlite3VdbeChangeEncoding(pRec, SQLITE_UTF8);
if( !realnum && sqlite3Atoi64(pRec->z, &value) ){
pRec->u.i = value;
MemSetTypeFlag(pRec, MEM_Int);
}else{
sqlite3VdbeMemRealify(pRec);
}
}
}
}
/*
** Processing is determine by the affinity parameter:
**
** SQLITE_AFF_INTEGER:
** SQLITE_AFF_REAL:
** SQLITE_AFF_NUMERIC:
** Try to convert pRec to an integer representation or a
** floating-point representation if an integer representation
** is not possible. Note that the integer representation is
** always preferred, even if the affinity is REAL, because
** an integer representation is more space efficient on disk.
**
** SQLITE_AFF_TEXT:
** Convert pRec to a text representation.
**
** SQLITE_AFF_NONE:
** No-op. pRec is unchanged.
*/
static void applyAffinity(
Mem *pRec, /* The value to apply affinity to */
char affinity, /* The affinity to be applied */
u8 enc /* Use this text encoding */
){
if( affinity==SQLITE_AFF_TEXT ){
/* Only attempt the conversion to TEXT if there is an integer or real
** representation (blob and NULL do not get converted) but no string
** representation.
*/
if( 0==(pRec->flags&MEM_Str) && (pRec->flags&(MEM_Real|MEM_Int)) ){
sqlite3VdbeMemStringify(pRec, enc);
}
pRec->flags &= ~(MEM_Real|MEM_Int);
}else if( affinity!=SQLITE_AFF_NONE ){
assert( affinity==SQLITE_AFF_INTEGER || affinity==SQLITE_AFF_REAL
|| affinity==SQLITE_AFF_NUMERIC );
applyNumericAffinity(pRec);
if( pRec->flags & MEM_Real ){
sqlite3VdbeIntegerAffinity(pRec);
}
}
}
/*
** Try to convert the type of a function argument or a result column
** into a numeric representation. Use either INTEGER or REAL whichever
** is appropriate. But only do the conversion if it is possible without
** loss of information and return the revised type of the argument.
**
** This is an EXPERIMENTAL api and is subject to change or removal.
*/
int sqlite3_value_numeric_type(sqlite3_value *pVal){
Mem *pMem = (Mem*)pVal;
applyNumericAffinity(pMem);
storeTypeInfo(pMem, 0);
return pMem->type;
}
/*
** Exported version of applyAffinity(). This one works on sqlite3_value*,
** not the internal Mem* type.
*/
void sqlite3ValueApplyAffinity(
sqlite3_value *pVal,
u8 affinity,
u8 enc
){
applyAffinity((Mem *)pVal, affinity, enc);
}
#ifdef SQLITE_DEBUG
/*
** Write a nice string representation of the contents of cell pMem
** into buffer zBuf, length nBuf.
*/
void sqlite3VdbeMemPrettyPrint(Mem *pMem, char *zBuf){
char *zCsr = zBuf;
int f = pMem->flags;
static const char *const encnames[] = {"(X)", "(8)", "(16LE)", "(16BE)"};
if( f&MEM_Blob ){
int i;
char c;
if( f & MEM_Dyn ){
c = 'z';
assert( (f & (MEM_Static|MEM_Ephem))==0 );
}else if( f & MEM_Static ){
c = 't';
assert( (f & (MEM_Dyn|MEM_Ephem))==0 );
}else if( f & MEM_Ephem ){
c = 'e';
assert( (f & (MEM_Static|MEM_Dyn))==0 );
}else{
c = 's';
}
sqlite3_snprintf(100, zCsr, "%c", c);
zCsr += strlen(zCsr);
sqlite3_snprintf(100, zCsr, "%d[", pMem->n);
zCsr += strlen(zCsr);
for(i=0; i<16 && i<pMem->n; i++){
sqlite3_snprintf(100, zCsr, "%02X", ((int)pMem->z[i] & 0xFF));
zCsr += strlen(zCsr);
}
for(i=0; i<16 && i<pMem->n; i++){
char z = pMem->z[i];
if( z<32 || z>126 ) *zCsr++ = '.';
else *zCsr++ = z;
}
sqlite3_snprintf(100, zCsr, "]%s", encnames[pMem->enc]);
zCsr += strlen(zCsr);
if( f & MEM_Zero ){
sqlite3_snprintf(100, zCsr,"+%lldz",pMem->u.i);
zCsr += strlen(zCsr);
}
*zCsr = '';
}else if( f & MEM_Str ){
int j, k;
zBuf[0] = ' ';
if( f & MEM_Dyn ){
zBuf[1] = 'z';
assert( (f & (MEM_Static|MEM_Ephem))==0 );
}else if( f & MEM_Static ){
zBuf[1] = 't';
assert( (f & (MEM_Dyn|MEM_Ephem))==0 );
}else if( f & MEM_Ephem ){
zBuf[1] = 'e';
assert( (f & (MEM_Static|MEM_Dyn))==0 );
}else{
zBuf[1] = 's';
}
k = 2;
sqlite3_snprintf(100, &zBuf[k], "%d", pMem->n);
k += strlen(&zBuf[k]);
zBuf[k++] = '[';
for(j=0; j<15 && j<pMem->n; j++){
u8 c = pMem->z[j];
if( c>=0x20 && c<0x7f ){
zBuf[k++] = c;
}else{
zBuf[k++] = '.';
}
}
zBuf[k++] = ']';
sqlite3_snprintf(100,&zBuf[k], encnames[pMem->enc]);
k += strlen(&zBuf[k]);
zBuf[k++] = 0;
}
}
#endif
#ifdef SQLITE_DEBUG
/*
** Print the value of a register for tracing purposes:
*/
static void memTracePrint(FILE *out, Mem *p){
if( p->flags & MEM_Null ){
fprintf(out, " NULL");
}else if( (p->flags & (MEM_Int|MEM_Str))==(MEM_Int|MEM_Str) ){
fprintf(out, " si:%lld", p->u.i);
}else if( p->flags & MEM_Int ){
fprintf(out, " i:%lld", p->u.i);
}else if( p->flags & MEM_Real ){
fprintf(out, " r:%g", p->r);
}else{
char zBuf[200];
sqlite3VdbeMemPrettyPrint(p, zBuf);
fprintf(out, " ");
fprintf(out, "%s", zBuf);
}
}
static void registerTrace(FILE *out, int iReg, Mem *p){
fprintf(out, "REG[%d] = ", iReg);
memTracePrint(out, p);
fprintf(out, "n");
}
#endif
#ifdef SQLITE_DEBUG
# define REGISTER_TRACE(R,M) if(p->trace&&R>0)registerTrace(p->trace,R,M)
#else
# define REGISTER_TRACE(R,M)
#endif
#ifdef VDBE_PROFILE
/*
** The following routine only works on pentium-class processors.
** It uses the RDTSC opcode to read the cycle count value out of the
** processor and returns that value. This can be used for high-res
** profiling.
*/
__inline__ unsigned long long int hwtime(void){
unsigned int lo, hi;
/* We cannot use "=A", since this would use %rax on x86_64 */
__asm__ __volatile__ ("rdtsc" : "=a" (lo), "=d" (hi));
return (unsigned long long int)hi << 32 | lo;
}
#endif
/*
** The CHECK_FOR_INTERRUPT macro defined here looks to see if the
** sqlite3_interrupt() routine has been called. If it has been, then
** processing of the VDBE program is interrupted.
**
** This macro added to every instruction that does a jump in order to
** implement a loop. This test used to be on every single instruction,
** but that meant we more testing that we needed. By only testing the
** flag on jump instructions, we get a (small) speed improvement.
*/
#define CHECK_FOR_INTERRUPT
if( db->u1.isInterrupted ) goto abort_due_to_interrupt;
/*
** Execute as much of a VDBE program as we can then return.
**
** sqlite3VdbeMakeReady() must be called before this routine in order to
** close the program with a final OP_Halt and to set up the callbacks
** and the error message pointer.
**
** Whenever a row or result data is available, this routine will either
** invoke the result callback (if there is one) or return with
** SQLITE_ROW.
**
** If an attempt is made to open a locked database, then this routine
** will either invoke the busy callback (if there is one) or it will
** return SQLITE_BUSY.
**
** If an error occurs, an error message is written to memory obtained
** from sqlite3_malloc() and p->zErrMsg is made to point to that memory.
** The error code is stored in p->rc and this routine returns SQLITE_ERROR.
**
** If the callback ever returns non-zero, then the program exits
** immediately. There will be no error message but the p->rc field is
** set to SQLITE_ABORT and this routine will return SQLITE_ERROR.
**
** A memory allocation error causes p->rc to be set to SQLITE_NOMEM and this
** routine to return SQLITE_ERROR.
**
** Other fatal errors return SQLITE_ERROR.
**
** After this routine has finished, sqlite3VdbeFinalize() should be
** used to clean up the mess that was left behind.
*/
int sqlite3VdbeExec(
Vdbe *p /* The VDBE */
){
int pc; /* The program counter */
Op *pOp; /* Current operation */
int rc = SQLITE_OK; /* Value to return */
sqlite3 *db = p->db; /* The database */
u8 encoding = ENC(db); /* The database encoding */
Mem *pIn1, *pIn2, *pIn3; /* Input operands */
Mem *pOut; /* Output operand */
u8 opProperty;
#ifdef VDBE_PROFILE
unsigned long long start; /* CPU clock count at start of opcode */
int origPc; /* Program counter at start of opcode */
#endif
#ifndef SQLITE_OMIT_PROGRESS_CALLBACK
int nProgressOps = 0; /* Opcodes executed since progress callback. */
#endif
assert( p->magic==VDBE_MAGIC_RUN ); /* sqlite3_step() verifies this */
assert( db->magic==SQLITE_MAGIC_BUSY );
sqlite3BtreeMutexArrayEnter(&p->aMutex);
if( p->rc==SQLITE_NOMEM ){
/* This happens if a malloc() inside a call to sqlite3_column_text() or
** sqlite3_column_text16() failed. */
goto no_mem;
}
assert( p->rc==SQLITE_OK || p->rc==SQLITE_BUSY );
p->rc = SQLITE_OK;
assert( p->explain==0 );
p->pResultSet = 0;
db->busyHandler.nBusy = 0;
CHECK_FOR_INTERRUPT;
sqlite3VdbeIOTraceSql(p);
#ifdef SQLITE_DEBUG
sqlite3FaultBenign(-1, 1);
if( p->pc==0 && ((p->db->flags & SQLITE_VdbeListing)!=0
|| sqlite3OsAccess(db->pVfs, "vdbe_explain", SQLITE_ACCESS_EXISTS)==1 )
){
int i;
printf("VDBE Program Listing:n");
sqlite3VdbePrintSql(p);
for(i=0; i<p->nOp; i++){
sqlite3VdbePrintOp(stdout, i, &p->aOp[i]);
}
}
if( sqlite3OsAccess(db->pVfs, "vdbe_trace", SQLITE_ACCESS_EXISTS)==1 ){
p->trace = stdout;
}
sqlite3FaultBenign(-1, 0);
#endif
for(pc=p->pc; rc==SQLITE_OK; pc++){
assert( pc>=0 && pc<p->nOp );
if( db->mallocFailed ) goto no_mem;
#ifdef VDBE_PROFILE
origPc = pc;
start = hwtime();
#endif
pOp = &p->aOp[pc];
/* Only allow tracing if SQLITE_DEBUG is defined.
*/
#ifdef SQLITE_DEBUG
if( p->trace ){
if( pc==0 ){
printf("VDBE Execution Trace:n");
sqlite3VdbePrintSql(p);
}
sqlite3VdbePrintOp(p->trace, pc, pOp);
}
if( p->trace==0 && pc==0 ){
sqlite3FaultBenign(-1, 1);
if( sqlite3OsAccess(db->pVfs, "vdbe_sqltrace", SQLITE_ACCESS_EXISTS)==1 ){
sqlite3VdbePrintSql(p);
}
sqlite3FaultBenign(-1, 0);
}
#endif
/* Check to see if we need to simulate an interrupt. This only happens
** if we have a special test build.
*/
#ifdef SQLITE_TEST
if( sqlite3_interrupt_count>0 ){
sqlite3_interrupt_count--;
if( sqlite3_interrupt_count==0 ){
sqlite3_interrupt(db);
}
}
#endif
#ifndef SQLITE_OMIT_PROGRESS_CALLBACK
/* Call the progress callback if it is configured and the required number
** of VDBE ops have been executed (either since this invocation of
** sqlite3VdbeExec() or since last time the progress callback was called).
** If the progress callback returns non-zero, exit the virtual machine with
** a return code SQLITE_ABORT.
*/
if( db->xProgress ){
if( db->nProgressOps==nProgressOps ){
int prc;
if( sqlite3SafetyOff(db) ) goto abort_due_to_misuse;
prc =db->xProgress(db->pProgressArg);
if( sqlite3SafetyOn(db) ) goto abort_due_to_misuse;
if( prc!=0 ){
rc = SQLITE_INTERRUPT;
goto vdbe_error_halt;
}
nProgressOps = 0;
}
nProgressOps++;
}
#endif
/* Do common setup processing for any opcode that is marked
** with the "out2-prerelease" tag. Such opcodes have a single
** output which is specified by the P2 parameter. The P2 register
** is initialized to a NULL.
*/
opProperty = opcodeProperty[pOp->opcode];
if( (opProperty & OPFLG_OUT2_PRERELEASE)!=0 ){
assert( pOp->p2>0 );
assert( pOp->p2<=p->nMem );
pOut = &p->aMem[pOp->p2];
sqlite3VdbeMemReleaseExternal(pOut);
pOut->flags = MEM_Null;
}else
/* Do common setup for opcodes marked with one of the following
** combinations of properties.
**
** in1
** in1 in2
** in1 in2 out3
** in1 in3
**
** Variables pIn1, pIn2, and pIn3 are made to point to appropriate
** registers for inputs. Variable pOut points to the output register.
*/
if( (opProperty & OPFLG_IN1)!=0 ){
assert( pOp->p1>0 );
assert( pOp->p1<=p->nMem );
pIn1 = &p->aMem[pOp->p1];
REGISTER_TRACE(pOp->p1, pIn1);
if( (opProperty & OPFLG_IN2)!=0 ){
assert( pOp->p2>0 );
assert( pOp->p2<=p->nMem );
pIn2 = &p->aMem[pOp->p2];
REGISTER_TRACE(pOp->p2, pIn2);
if( (opProperty & OPFLG_OUT3)!=0 ){
assert( pOp->p3>0 );
assert( pOp->p3<=p->nMem );
pOut = &p->aMem[pOp->p3];
}
}else if( (opProperty & OPFLG_IN3)!=0 ){
assert( pOp->p3>0 );
assert( pOp->p3<=p->nMem );
pIn3 = &p->aMem[pOp->p3];
REGISTER_TRACE(pOp->p3, pIn3);
}
}else if( (opProperty & OPFLG_IN2)!=0 ){
assert( pOp->p2>0 );
assert( pOp->p2<=p->nMem );
pIn2 = &p->aMem[pOp->p2];
REGISTER_TRACE(pOp->p2, pIn2);
}else if( (opProperty & OPFLG_IN3)!=0 ){
assert( pOp->p3>0 );
assert( pOp->p3<=p->nMem );
pIn3 = &p->aMem[pOp->p3];
REGISTER_TRACE(pOp->p3, pIn3);
}
switch( pOp->opcode ){
/*****************************************************************************
** What follows is a massive switch statement where each case implements a
** separate instruction in the virtual machine. If we follow the usual
** indentation conventions, each case should be indented by 6 spaces. But
** that is a lot of wasted space on the left margin. So the code within
** the switch statement will break with convention and be flush-left. Another
** big comment (similar to this one) will mark the point in the code where
** we transition back to normal indentation.
**
** The formatting of each case is important. The makefile for SQLite
** generates two C files "opcodes.h" and "opcodes.c" by scanning this
** file looking for lines that begin with "case OP_". The opcodes.h files
** will be filled with #defines that give unique integer values to each
** opcode and the opcodes.c file is filled with an array of strings where
** each string is the symbolic name for the corresponding opcode. If the
** case statement is followed by a comment of the form "/# same as ... #/"
** that comment is used to determine the particular value of the opcode.
**
** Other keywords in the comment that follows each case are used to
** construct the OPFLG_INITIALIZER value that initializes opcodeProperty[].
** Keywords include: in1, in2, in3, out2_prerelease, out2, out3. See
** the mkopcodeh.awk script for additional information.
**
** Documentation about VDBE opcodes is generated by scanning this file
** for lines of that contain "Opcode:". That line and all subsequent
** comment lines are used in the generation of the opcode.html documentation
** file.
**
** SUMMARY:
**
** Formatting is important to scripts that scan this file.
** Do not deviate from the formatting style currently in use.
**
*****************************************************************************/
/* Opcode: Goto * P2 * * *
**
** An unconditional jump to address P2.
** The next instruction executed will be
** the one at index P2 from the beginning of
** the program.
*/
case OP_Goto: { /* jump */
CHECK_FOR_INTERRUPT;
pc = pOp->p2 - 1;
break;
}
/* Opcode: Gosub * P2 * * *
**
** Push the current address plus 1 onto the return address stack
** and then jump to address P2.
**
** The return address stack is of limited depth. If too many
** OP_Gosub operations occur without intervening OP_Returns, then
** the return address stack will fill up and processing will abort
** with a fatal error.
*/
case OP_Gosub: { /* jump */
assert( p->returnDepth<sizeof(p->returnStack)/sizeof(p->returnStack[0]) );
p->returnStack[p->returnDepth++] = pc+1;
pc = pOp->p2 - 1;
break;
}
/* Opcode: Return * * * * *
**
** Jump immediately to the next instruction after the last unreturned
** OP_Gosub. If an OP_Return has occurred for all OP_Gosubs, then
** processing aborts with a fatal error.
*/
case OP_Return: {
assert( p->returnDepth>0 );
p->returnDepth--;
pc = p->returnStack[p->returnDepth] - 1;
break;
}
/* Opcode: Halt P1 P2 * P4 *
**
** Exit immediately. All open cursors, Fifos, etc are closed
** automatically.
**
** P1 is the result code returned by sqlite3_exec(), sqlite3_reset(),
** or sqlite3_finalize(). For a normal halt, this should be SQLITE_OK (0).
** For errors, it can be some other value. If P1!=0 then P2 will determine
** whether or not to rollback the current transaction. Do not rollback
** if P2==OE_Fail. Do the rollback if P2==OE_Rollback. If P2==OE_Abort,
** then back out all changes that have occurred during this execution of the
** VDBE, but do not rollback the transaction.
**
** If P4 is not null then it is an error message string.
**
** There is an implied "Halt 0 0 0" instruction inserted at the very end of
** every program. So a jump past the last instruction of the program
** is the same as executing Halt.
*/
case OP_Halt: {
p->rc = pOp->p1;
p->pc = pc;
p->errorAction = pOp->p2;
if( pOp->p4.z ){
sqlite3SetString(&p->zErrMsg, pOp->p4.z, (char*)0);
}
rc = sqlite3VdbeHalt(p);
assert( rc==SQLITE_BUSY || rc==SQLITE_OK );
if( rc==SQLITE_BUSY ){
p->rc = rc = SQLITE_BUSY;
}else{
rc = p->rc ? SQLITE_ERROR : SQLITE_DONE;
}
goto vdbe_return;
}
/* Opcode: Integer P1 P2 * * *
**
** The 32-bit integer value P1 is written into register P2.
*/
case OP_Integer: { /* out2-prerelease */
pOut->flags = MEM_Int;
pOut->u.i = pOp->p1;
break;
}
/* Opcode: Int64 * P2 * P4 *
**
** P4 is a pointer to a 64-bit integer value.
** Write that value into register P2.
*/
case OP_Int64: { /* out2-prerelease */
assert( pOp->p4.pI64!=0 );
pOut->flags = MEM_Int;
pOut->u.i = *pOp->p4.pI64;
break;
}
/* Opcode: Real * P2 * P4 *
**
** P4 is a pointer to a 64-bit floating point value.
** Write that value into register P2.
*/
case OP_Real: { /* same as TK_FLOAT, out2-prerelease */
pOut->flags = MEM_Real;
pOut->r = *pOp->p4.pReal;
break;
}
/* Opcode: String8 * P2 * P4 *
**
** P4 points to a nul terminated UTF-8 string. This opcode is transformed
** into an OP_String before it is executed for the first time.
*/
case OP_String8: { /* same as TK_STRING, out2-prerelease */
assert( pOp->p4.z!=0 );
pOp->opcode = OP_String;
pOp->p1 = strlen(pOp->p4.z);
#ifndef SQLITE_OMIT_UTF16
if( encoding!=SQLITE_UTF8 ){
sqlite3VdbeMemSetStr(pOut, pOp->p4.z, -1, SQLITE_UTF8, SQLITE_STATIC);
if( SQLITE_OK!=sqlite3VdbeChangeEncoding(pOut, encoding) ) goto no_mem;
if( SQLITE_OK!=sqlite3VdbeMemDynamicify(pOut) ) goto no_mem;
pOut->zMalloc = 0;
pOut->flags |= MEM_Static;
pOut->flags &= ~MEM_Dyn;
if( pOp->p4type==P4_DYNAMIC ){
sqlite3_free(pOp->p4.z);
}
pOp->p4type = P4_DYNAMIC;
pOp->p4.z = pOut->z;
pOp->p1 = pOut->n;
if( pOp->p1>db->aLimit[SQLITE_LIMIT_LENGTH] ){
goto too_big;
}
UPDATE_MAX_BLOBSIZE(pOut);
break;
}
#endif
if( pOp->p1>db->aLimit[SQLITE_LIMIT_LENGTH] ){
goto too_big;
}
/* Fall through to the next case, OP_String */
}
/* Opcode: String P1 P2 * P4 *
**
** The string value P4 of length P1 (bytes) is stored in register P2.
*/
case OP_String: { /* out2-prerelease */
assert( pOp->p4.z!=0 );
pOut->flags = MEM_Str|MEM_Static|MEM_Term;
pOut->z = pOp->p4.z;
pOut->n = pOp->p1;
pOut->enc = encoding;
UPDATE_MAX_BLOBSIZE(pOut);
break;
}
/* Opcode: Null * P2 * * *
**
** Write a NULL into register P2.
*/
case OP_Null: { /* out2-prerelease */
break;
}
#ifndef SQLITE_OMIT_BLOB_LITERAL
/* Opcode: Blob P1 P2 * P4
**
** P4 points to a blob of data P1 bytes long. Store this
** blob in register P2. This instruction is not coded directly
** by the compiler. Instead, the compiler layer specifies
** an OP_HexBlob opcode, with the hex string representation of
** the blob as P4. This opcode is transformed to an OP_Blob
** the first time it is executed.
*/
case OP_Blob: { /* out2-prerelease */
assert( pOp->p1 <= SQLITE_MAX_LENGTH );
sqlite3VdbeMemSetStr(pOut, pOp->p4.z, pOp->p1, 0, 0);
pOut->enc = encoding;
UPDATE_MAX_BLOBSIZE(pOut);
break;
}
#endif /* SQLITE_OMIT_BLOB_LITERAL */
/* Opcode: Variable P1 P2 * * *
**
** The value of variable P1 is written into register P2. A variable is
** an unknown in the original SQL string as handed to sqlite3_compile().
** Any occurance of the '?' character in the original SQL is considered
** a variable. Variables in the SQL string are number from left to
** right beginning with 1. The values of variables are set using the
** sqlite3_bind() API.
*/
case OP_Variable: { /* out2-prerelease */
int j = pOp->p1 - 1;
Mem *pVar;
assert( j>=0 && j<p->nVar );
pVar = &p->aVar[j];
if( sqlite3VdbeMemTooBig(pVar) ){
goto too_big;
}
sqlite3VdbeMemShallowCopy(pOut, &p->aVar[j], MEM_Static);
UPDATE_MAX_BLOBSIZE(pOut);
break;
}
/* Opcode: Move P1 P2 * * *
**
** Move the value in register P1 over into register P2. Register P1
** is left holding a NULL. It is an error for P1 and P2 to be the
** same register.
*/
case OP_Move: {
char *zMalloc;
assert( pOp->p1>0 );
assert( pOp->p1<=p->nMem );
pIn1 = &p->aMem[pOp->p1];
REGISTER_TRACE(pOp->p1, pIn1);
assert( pOp->p2>0 );
assert( pOp->p2<=p->nMem );
pOut = &p->aMem[pOp->p2];
assert( pOut!=pIn1 );
zMalloc = pOut->zMalloc;
pOut->zMalloc = 0;
sqlite3VdbeMemMove(pOut, pIn1);
pIn1->zMalloc = zMalloc;
REGISTER_TRACE(pOp->p2, pOut);
break;
}
/* Opcode: Copy P1 P2 * * *
**
** Make a copy of register P1 into register P2.
**
** This instruction makes a deep copy of the value. A duplicate
** is made of any string or blob constant. See also OP_SCopy.
*/
case OP_Copy: {
assert( pOp->p1>0 );
assert( pOp->p1<=p->nMem );
pIn1 = &p->aMem[pOp->p1];
REGISTER_TRACE(pOp->p1, pIn1);
assert( pOp->p2>0 );
assert( pOp->p2<=p->nMem );
pOut = &p->aMem[pOp->p2];
assert( pOut!=pIn1 );
sqlite3VdbeMemShallowCopy(pOut, pIn1, MEM_Ephem);
Deephemeralize(pOut);
REGISTER_TRACE(pOp->p2, pOut);
break;
}
/* Opcode: SCopy P1 P2 * * *
**
** Make a shallow copy of register P1 into register P2.
**
** This instruction makes a shallow copy of the value. If the value
** is a string or blob, then the copy is only a pointer to the
** original and hence if the original changes so will the copy.
** Worse, if the original is deallocated, the copy becomes invalid.
** Thus the program must guarantee that the original will not change
** during the lifetime of the copy. Use OP_Copy to make a complete
** copy.
*/
case OP_SCopy: {
assert( pOp->p1>0 );
assert( pOp->p1<=p->nMem );
pIn1 = &p->aMem[pOp->p1];
REGISTER_TRACE(pOp->p1, pIn1);
assert( pOp->p2>0 );
assert( pOp->p2<=p->nMem );
pOut = &p->aMem[pOp->p2];
assert( pOut!=pIn1 );
sqlite3VdbeMemShallowCopy(pOut, pIn1, MEM_Ephem);
REGISTER_TRACE(pOp->p2, pOut);
break;
}
/* Opcode: ResultRow P1 P2 * * *
**
** The registers P1 throught P1+P2-1 contain a single row of
** results. This opcode causes the sqlite3_step() call to terminate
** with an SQLITE_ROW return code and it sets up the sqlite3_stmt
** structure to provide access to the top P1 values as the result
** row.
*/
case OP_ResultRow: {
Mem *pMem;
int i;
assert( p->nResColumn==pOp->p2 );
assert( pOp->p1>0 );
assert( pOp->p1+pOp->p2<=p->nMem );
/* Invalidate all ephemeral cursor row caches */
p->cacheCtr = (p->cacheCtr + 2)|1;
/* Make sure the results of the current row are 00 terminated
** and have an assigned type. The results are deephemeralized as
** as side effect.
*/
pMem = p->pResultSet = &p->aMem[pOp->p1];
for(i=0; i<pOp->p2; i++){
sqlite3VdbeMemNulTerminate(&pMem[i]);
storeTypeInfo(&pMem[i], encoding);
}
if( db->mallocFailed ) goto no_mem;
/* Return SQLITE_ROW
*/
p->nCallback++;
p->pc = pc + 1;
rc = SQLITE_ROW;
goto vdbe_return;
}
/* Opcode: Concat P1 P2 P3 * *
**
** Add the text in register P1 onto the end of the text in
** register P2 and store the result in register P3.
** If either the P1 or P2 text are NULL then store NULL in P3.
**
** P3 = P2 || P1
**
** It is illegal for P1 and P3 to be the same register. Sometimes,
** if P3 is the same register as P2, the implementation is able
** to avoid a memcpy().
*/
case OP_Concat: { /* same as TK_CONCAT, in1, in2, out3 */
i64 nByte;
assert( pIn1!=pOut );
if( (pIn1->flags | pIn2->flags) & MEM_Null ){
sqlite3VdbeMemSetNull(pOut);
break;
}
ExpandBlob(pIn1);
Stringify(pIn1, encoding);
ExpandBlob(pIn2);
Stringify(pIn2, encoding);
nByte = pIn1->n + pIn2->n;
if( nByte>db->aLimit[SQLITE_LIMIT_LENGTH] ){
goto too_big;
}
MemSetTypeFlag(pOut, MEM_Str);
if( sqlite3VdbeMemGrow(pOut, nByte+2, pOut==pIn2) ){
goto no_mem;
}
if( pOut!=pIn2 ){
memcpy(pOut->z, pIn2->z, pIn2->n);
}
memcpy(&pOut->z[pIn2->n], pIn1->z, pIn1->n);
pOut->z[nByte] = 0;
pOut->z[nByte+1] = 0;
pOut->flags |= MEM_Term;
pOut->n = nByte;
pOut->enc = encoding;
UPDATE_MAX_BLOBSIZE(pOut);
break;
}
/* Opcode: Add P1 P2 P3 * *
**
** Add the value in register P1 to the value in register P2
** and store the result in regiser P3.
** If either input is NULL, the result is NULL.
*/
/* Opcode: Multiply P1 P2 P3 * *
**
**
** Multiply the value in regiser P1 by the value in regiser P2
** and store the result in register P3.
** If either input is NULL, the result is NULL.
*/
/* Opcode: Subtract P1 P2 P3 * *
**
** Subtract the value in register P1 from the value in register P2
** and store the result in register P3.
** If either input is NULL, the result is NULL.
*/
/* Opcode: Divide P1 P2 P3 * *
**
** Divide the value in register P1 by the value in register P2
** and store the result in register P3. If the value in register P2
** is zero, then the result is NULL.
** If either input is NULL, the result is NULL.
*/
/* Opcode: Remainder P1 P2 P3 * *
**
** Compute the remainder after integer division of the value in
** register P1 by the value in register P2 and store the result in P3.
** If the value in register P2 is zero the result is NULL.
** If either operand is NULL, the result is NULL.
*/
case OP_Add: /* same as TK_PLUS, in1, in2, out3 */
case OP_Subtract: /* same as TK_MINUS, in1, in2, out3 */
case OP_Multiply: /* same as TK_STAR, in1, in2, out3 */
case OP_Divide: /* same as TK_SLASH, in1, in2, out3 */
case OP_Remainder: { /* same as TK_REM, in1, in2, out3 */
int flags;
flags = pIn1->flags | pIn2->flags;
if( (flags & MEM_Null)!=0 ) goto arithmetic_result_is_null;
if( (pIn1->flags & pIn2->flags & MEM_Int)==MEM_Int ){
i64 a, b;
a = pIn1->u.i;
b = pIn2->u.i;
switch( pOp->opcode ){
case OP_Add: b += a; break;
case OP_Subtract: b -= a; break;
case OP_Multiply: b *= a; break;
case OP_Divide: {
if( a==0 ) goto arithmetic_result_is_null;
/* Dividing the largest possible negative 64-bit integer (1<<63) by
** -1 returns an integer to large to store in a 64-bit data-type. On
** some architectures, the value overflows to (1<<63). On others,
** a SIGFPE is issued. The following statement normalizes this
** behaviour so that all architectures behave as if integer
** overflow occured.
*/
if( a==-1 && b==(((i64)1)<<63) ) a = 1;
b /= a;
break;
}
default: {
if( a==0 ) goto arithmetic_result_is_null;
if( a==-1 ) a = 1;
b %= a;
break;
}
}
pOut->u.i = b;
MemSetTypeFlag(pOut, MEM_Int);
}else{
double a, b;
a = sqlite3VdbeRealValue(pIn1);
b = sqlite3VdbeRealValue(pIn2);
switch( pOp->opcode ){
case OP_Add: b += a; break;
case OP_Subtract: b -= a; break;
case OP_Multiply: b *= a; break;
case OP_Divide: {
if( a==0.0 ) goto arithmetic_result_is_null;
b /= a;
break;
}
default: {
i64 ia = (i64)a;
i64 ib = (i64)b;
if( ia==0 ) goto arithmetic_result_is_null;
if( ia==-1 ) ia = 1;
b = ib % ia;
break;
}
}
if( sqlite3_isnan(b) ){
goto arithmetic_result_is_null;
}
pOut->r = b;
MemSetTypeFlag(pOut, MEM_Real);
if( (flags & MEM_Real)==0 ){
sqlite3VdbeIntegerAffinity(pOut);
}
}
break;
arithmetic_result_is_null:
sqlite3VdbeMemSetNull(pOut);
break;
}
/* Opcode: CollSeq * * P4
**
** P4 is a pointer to a CollSeq struct. If the next call to a user function
** or aggregate calls sqlite3GetFuncCollSeq(), this collation sequence will
** be returned. This is used by the built-in min(), max() and nullif()
** functions.
**
** The interface used by the implementation of the aforementioned functions
** to retrieve the collation sequence set by this opcode is not available
** publicly, only to user functions defined in func.c.
*/
case OP_CollSeq: {
assert( pOp->p4type==P4_COLLSEQ );
break;
}
/* Opcode: Function P1 P2 P3 P4 P5
**
** Invoke a user function (P4 is a pointer to a Function structure that
** defines the function) with P5 arguments taken from register P2 and
** successors. The result of the function is stored in register P3.
** Register P3 must not be one of the function inputs.
**
** P1 is a 32-bit bitmask indicating whether or not each argument to the
** function was determined to be constant at compile time. If the first
** argument was constant then bit 0 of P1 is set. This is used to determine
** whether meta data associated with a user function argument using the
** sqlite3_set_auxdata() API may be safely retained until the next
** invocation of this opcode.
**
** See also: AggStep and AggFinal
*/
case OP_Function: {
int i;
Mem *pArg;
sqlite3_context ctx;
sqlite3_value **apVal;
int n = pOp->p5;
apVal = p->apArg;
assert( apVal || n==0 );
assert( n==0 || (pOp->p2>0 && pOp->p2+n<=p->nMem) );
assert( pOp->p3<pOp->p2 || pOp->p3>=pOp->p2+n );
pArg = &p->aMem[pOp->p2];
for(i=0; i<n; i++, pArg++){
apVal[i] = pArg;
storeTypeInfo(pArg, encoding);
REGISTER_TRACE(pOp->p2, pArg);
}
assert( pOp->p4type==P4_FUNCDEF || pOp->p4type==P4_VDBEFUNC );
if( pOp->p4type==P4_FUNCDEF ){
ctx.pFunc = pOp->p4.pFunc;
ctx.pVdbeFunc = 0;
}else{
ctx.pVdbeFunc = (VdbeFunc*)pOp->p4.pVdbeFunc;
ctx.pFunc = ctx.pVdbeFunc->pFunc;
}
assert( pOp->p3>0 && pOp->p3<=p->nMem );
pOut = &p->aMem[pOp->p3];
ctx.s.flags = MEM_Null;
ctx.s.db = db;
ctx.s.xDel = 0;
ctx.s.zMalloc = 0;
/* The output cell may already have a buffer allocated. Move
** the pointer to ctx.s so in case the user-function can use
** the already allocated buffer instead of allocating a new one.
*/
sqlite3VdbeMemMove(&ctx.s, pOut);
MemSetTypeFlag(&ctx.s, MEM_Null);
ctx.isError = 0;
if( ctx.pFunc->needCollSeq ){
assert( pOp>p->aOp );
assert( pOp[-1].p4type==P4_COLLSEQ );
assert( pOp[-1].opcode==OP_CollSeq );
ctx.pColl = pOp[-1].p4.pColl;
}
if( sqlite3SafetyOff(db) ) goto abort_due_to_misuse;
(*ctx.pFunc->xFunc)(&ctx, n, apVal);
if( sqlite3SafetyOn(db) ){
sqlite3VdbeMemRelease(&ctx.s);
goto abort_due_to_misuse;
}
if( db->mallocFailed ){
/* Even though a malloc() has failed, the implementation of the
** user function may have called an sqlite3_result_XXX() function
** to return a value. The following call releases any resources
** associated with such a value.
**
** Note: Maybe MemRelease() should be called if sqlite3SafetyOn()
** fails also (the if(...) statement above). But if people are
** misusing sqlite, they have bigger problems than a leaked value.
*/
sqlite3VdbeMemRelease(&ctx.s);
goto no_mem;
}
/* If any auxilary data functions have been called by this user function,
** immediately call the destructor for any non-static values.
*/
if( ctx.pVdbeFunc ){
sqlite3VdbeDeleteAuxData(ctx.pVdbeFunc, pOp->p1);
pOp->p4.pVdbeFunc = ctx.pVdbeFunc;
pOp->p4type = P4_VDBEFUNC;
}
/* If the function returned an error, throw an exception */
if( ctx.isError ){
sqlite3SetString(&p->zErrMsg, sqlite3_value_text(&ctx.s), (char*)0);
rc = ctx.isError;
}
/* Copy the result of the function into register P3 */
sqlite3VdbeChangeEncoding(&ctx.s, encoding);
sqlite3VdbeMemMove(pOut, &ctx.s);
if( sqlite3VdbeMemTooBig(pOut) ){
goto too_big;
}
REGISTER_TRACE(pOp->p3, pOut);
UPDATE_MAX_BLOBSIZE(pOut);
break;
}
/* Opcode: BitAnd P1 P2 P3 * *
**
** Take the bit-wise AND of the values in register P1 and P2 and
** store the result in register P3.
** If either input is NULL, the result is NULL.
*/
/* Opcode: BitOr P1 P2 P3 * *
**
** Take the bit-wise OR of the values in register P1 and P2 and
** store the result in register P3.
** If either input is NULL, the result is NULL.
*/
/* Opcode: ShiftLeft P1 P2 P3 * *
**
** Shift the integer value in register P2 to the left by the
** number of bits specified by the integer in regiser P1.
** Store the result in register P3.
** If either input is NULL, the result is NULL.
*/
/* Opcode: ShiftRight P1 P2 P3 * *
**
** Shift the integer value in register P2 to the right by the
** number of bits specified by the integer in register P1.
** Store the result in register P3.
** If either input is NULL, the result is NULL.
*/
case OP_BitAnd: /* same as TK_BITAND, in1, in2, out3 */
case OP_BitOr: /* same as TK_BITOR, in1, in2, out3 */
case OP_ShiftLeft: /* same as TK_LSHIFT, in1, in2, out3 */
case OP_ShiftRight: { /* same as TK_RSHIFT, in1, in2, out3 */
i64 a, b;
if( (pIn1->flags | pIn2->flags) & MEM_Null ){
sqlite3VdbeMemSetNull(pOut);
break;
}
a = sqlite3VdbeIntValue(pIn2);
b = sqlite3VdbeIntValue(pIn1);
switch( pOp->opcode ){
case OP_BitAnd: a &= b; break;
case OP_BitOr: a |= b; break;
case OP_ShiftLeft: a <<= b; break;
default: assert( pOp->opcode==OP_ShiftRight );
a >>= b; break;
}
pOut->u.i = a;
MemSetTypeFlag(pOut, MEM_Int);
break;
}
/* Opcode: AddImm P1 P2 * * *
**
** Add the constant P2 the value in register P1.
** The result is always an integer.
**
** To force any register to be an integer, just add 0.
*/
case OP_AddImm: { /* in1 */
sqlite3VdbeMemIntegerify(pIn1);
pIn1->u.i += pOp->p2;
break;
}
/* Opcode: ForceInt P1 P2 P3 * *
**
** Convert value in register P1 into an integer. If the value
** in P1 is not numeric (meaning that is is a NULL or a string that
** does not look like an integer or floating point number) then
** jump to P2. If the value in P1 is numeric then
** convert it into the least integer that is greater than or equal to its
** current value if P3==0, or to the least integer that is strictly
** greater than its current value if P3==1.
*/
case OP_ForceInt: { /* jump, in1 */
i64 v;
applyAffinity(pIn1, SQLITE_AFF_NUMERIC, encoding);
if( (pIn1->flags & (MEM_Int|MEM_Real))==0 ){
pc = pOp->p2 - 1;
break;
}
if( pIn1->flags & MEM_Int ){
v = pIn1->u.i + (pOp->p3!=0);
}else{
assert( pIn1->flags & MEM_Real );
v = (sqlite3_int64)pIn1->r;
if( pIn1->r>(double)v ) v++;
if( pOp->p3 && pIn1->r==(double)v ) v++;
}
pIn1->u.i = v;
MemSetTypeFlag(pIn1, MEM_Int);
break;
}
/* Opcode: MustBeInt P1 P2 * * *
**
** Force the value in register P1 to be an integer. If the value
** in P1 is not an integer and cannot be converted into an integer
** without data loss, then jump immediately to P2, or if P2==0
** raise an SQLITE_MISMATCH exception.
*/
case OP_MustBeInt: { /* jump, in1 */
applyAffinity(pIn1, SQLITE_AFF_NUMERIC, encoding);
if( (pIn1->flags & MEM_Int)==0 ){
if( pOp->p2==0 ){
rc = SQLITE_MISMATCH;
goto abort_due_to_error;
}else{
pc = pOp->p2 - 1;
}
}else{
MemSetTypeFlag(pIn1, MEM_Int);
}
break;
}
/* Opcode: RealAffinity P1 * * * *
**
** If register P1 holds an integer convert it to a real value.
**
** This opcode is used when extracting information from a column that
** has REAL affinity. Such column values may still be stored as
** integers, for space efficiency, but after extraction we want them
** to have only a real value.
*/
case OP_RealAffinity: { /* in1 */
if( pIn1->flags & MEM_Int ){
sqlite3VdbeMemRealify(pIn1);
}
break;
}
#ifndef SQLITE_OMIT_CAST
/* Opcode: ToText P1 * * * *
**
** Force the value in register P1 to be text.
** If the value is numeric, convert it to a string using the
** equivalent of printf(). Blob values are unchanged and
** are afterwards simply interpreted as text.
**
** A NULL value is not changed by this routine. It remains NULL.
*/
case OP_ToText: { /* same as TK_TO_TEXT, in1 */
if( pIn1->flags & MEM_Null ) break;
assert( MEM_Str==(MEM_Blob>>3) );
pIn1->flags |= (pIn1->flags&MEM_Blob)>>3;
applyAffinity(pIn1, SQLITE_AFF_TEXT, encoding);
rc = ExpandBlob(pIn1);
assert( pIn1->flags & MEM_Str || db->mallocFailed );
pIn1->flags &= ~(MEM_Int|MEM_Real|MEM_Blob);
UPDATE_MAX_BLOBSIZE(pIn1);
break;
}
/* Opcode: ToBlob P1 * * * *
**
** Force the value in register P1 to be a BLOB.
** If the value is numeric, convert it to a string first.
** Strings are simply reinterpreted as blobs with no change
** to the underlying data.
**
** A NULL value is not changed by this routine. It remains NULL.
*/
case OP_ToBlob: { /* same as TK_TO_BLOB, in1 */
if( pIn1->flags & MEM_Null ) break;
if( (pIn1->flags & MEM_Blob)==0 ){
applyAffinity(pIn1, SQLITE_AFF_TEXT, encoding);
assert( pIn1->flags & MEM_Str || db->mallocFailed );
}
MemSetTypeFlag(pIn1, MEM_Blob);
UPDATE_MAX_BLOBSIZE(pIn1);
break;
}
/* Opcode: ToNumeric P1 * * * *
**
** Force the value in register P1 to be numeric (either an
** integer or a floating-point number.)
** If the value is text or blob, try to convert it to an using the
** equivalent of atoi() or atof() and store 0 if no such conversion
** is possible.
**
** A NULL value is not changed by this routine. It remains NULL.
*/
case OP_ToNumeric: { /* same as TK_TO_NUMERIC, in1 */
if( (pIn1->flags & (MEM_Null|MEM_Int|MEM_Real))==0 ){
sqlite3VdbeMemNumerify(pIn1);
}
break;
}
#endif /* SQLITE_OMIT_CAST */
/* Opcode: ToInt P1 * * * *
**
** Force the value in register P1 be an integer. If
** The value is currently a real number, drop its fractional part.
** If the value is text or blob, try to convert it to an integer using the
** equivalent of atoi() and store 0 if no such conversion is possible.
**
** A NULL value is not changed by this routine. It remains NULL.
*/
case OP_ToInt: { /* same as TK_TO_INT, in1 */
if( (pIn1->flags & MEM_Null)==0 ){
sqlite3VdbeMemIntegerify(pIn1);
}
break;
}
#ifndef SQLITE_OMIT_CAST
/* Opcode: ToReal P1 * * * *
**
** Force the value in register P1 to be a floating point number.
** If The value is currently an integer, convert it.
** If the value is text or blob, try to convert it to an integer using the
** equivalent of atoi() and store 0.0 if no such conversion is possible.
**
** A NULL value is not changed by this routine. It remains NULL.
*/
case OP_ToReal: { /* same as TK_TO_REAL, in1 */
if( (pIn1->flags & MEM_Null)==0 ){
sqlite3VdbeMemRealify(pIn1);
}
break;
}
#endif /* SQLITE_OMIT_CAST */
/* Opcode: Lt P1 P2 P3 P4 P5
**
** Compare the values in register P1 and P3. If reg(P3)<reg(P1) then
** jump to address P2.
**
** If the SQLITE_JUMPIFNULL bit of P5 is set and either reg(P1) or
** reg(P3) is NULL then take the jump. If the SQLITE_JUMPIFNULL
** bit is clear then fall thru if either operand is NULL.
**
** If the SQLITE_NULLEQUAL bit of P5 is set then treat NULL operands
** as being equal to one another. Normally NULLs are not equal to
** anything including other NULLs.
**
** The SQLITE_AFF_MASK portion of P5 must be an affinity character -
** SQLITE_AFF_TEXT, SQLITE_AFF_INTEGER, and so forth. An attempt is made
** to coerce both inputs according to this affinity before the
** comparison is made. If the SQLITE_AFF_MASK is 0x00, then numeric
** affinity is used. Note that the affinity conversions are stored
** back into the input registers P1 and P3. So this opcode can cause
** persistent changes to registers P1 and P3.
**
** Once any conversions have taken place, and neither value is NULL,
** the values are compared. If both values are blobs then memcmp() is
** used to determine the results of the comparison. If both values
** are text, then the appropriate collating function specified in
** P4 is used to do the comparison. If P4 is not specified then
** memcmp() is used to compare text string. If both values are
** numeric, then a numeric comparison is used. If the two values
** are of different types, then numbers are considered less than
** strings and strings are considered less than blobs.
**
** If the SQLITE_STOREP2 bit of P5 is set, then do not jump. Instead,
** store a boolean result (either 0, or 1, or NULL) in register P2.
*/
/* Opcode: Ne P1 P2 P3 P4 P5
**
** This works just like the Lt opcode except that the jump is taken if
** the operands in registers P1 and P3 are not equal. See the Lt opcode for
** additional information.
*/
/* Opcode: Eq P1 P2 P3 P4 P5
**
** This works just like the Lt opcode except that the jump is taken if
** the operands in registers P1 and P3 are equal.
** See the Lt opcode for additional information.
*/
/* Opcode: Le P1 P2 P3 P4 P5
**
** This works just like the Lt opcode except that the jump is taken if
** the content of register P3 is less than or equal to the content of
** register P1. See the Lt opcode for additional information.
*/
/* Opcode: Gt P1 P2 P3 P4 P5
**
** This works just like the Lt opcode except that the jump is taken if
** the content of register P3 is greater than the content of
** register P1. See the Lt opcode for additional information.
*/
/* Opcode: Ge P1 P2 P3 P4 P5
**
** This works just like the Lt opcode except that the jump is taken if
** the content of register P3 is greater than or equal to the content of
** register P1. See the Lt opcode for additional information.
*/
case OP_Eq: /* same as TK_EQ, jump, in1, in3 */
case OP_Ne: /* same as TK_NE, jump, in1, in3 */
case OP_Lt: /* same as TK_LT, jump, in1, in3 */
case OP_Le: /* same as TK_LE, jump, in1, in3 */
case OP_Gt: /* same as TK_GT, jump, in1, in3 */
case OP_Ge: { /* same as TK_GE, jump, in1, in3 */
int flags;
int res;
char affinity;
Mem x1, x3;
flags = pIn1->flags|pIn3->flags;
if( flags&MEM_Null ){
if( (pOp->p5 & SQLITE_NULLEQUAL)!=0 ){
/*
** When SQLITE_NULLEQUAL set and either operand is NULL
** then both operands are converted to integers prior to being
** passed down into the normal comparison logic below.
** NULL operands are converted to zero and non-NULL operands
** are converted to 1. Thus, for example, with SQLITE_NULLEQUAL
** set, NULL==NULL is true whereas it would normally NULL.
** Similarly, NULL!=123 is true.
*/
x1.flags = MEM_Int;
x1.u.i = (pIn1->flags & MEM_Null)==0;
pIn1 = &x1;
x3.flags = MEM_Int;
x3.u.i = (pIn3->flags & MEM_Null)==0;
pIn3 = &x3;
}else{
/* If the SQLITE_NULLEQUAL bit is clear and either operand is NULL then
** the result is always NULL. The jump is taken if the
** SQLITE_JUMPIFNULL bit is set.
*/
if( pOp->p5 & SQLITE_STOREP2 ){
pOut = &p->aMem[pOp->p2];
MemSetTypeFlag(pOut, MEM_Null);
REGISTER_TRACE(pOp->p2, pOut);
}else if( pOp->p5 & SQLITE_JUMPIFNULL ){
pc = pOp->p2-1;
}
break;
}
}
affinity = pOp->p5 & SQLITE_AFF_MASK;
if( affinity ){
applyAffinity(pIn1, affinity, encoding);
applyAffinity(pIn3, affinity, encoding);
}
assert( pOp->p4type==P4_COLLSEQ || pOp->p4.pColl==0 );
ExpandBlob(pIn1);
ExpandBlob(pIn3);
res = sqlite3MemCompare(pIn3, pIn1, pOp->p4.pColl);
switch( pOp->opcode ){
case OP_Eq: res = res==0; break;
case OP_Ne: res = res!=0; break;
case OP_Lt: res = res<0; break;
case OP_Le: res = res<=0; break;
case OP_Gt: res = res>0; break;
default: res = res>=0; break;
}
if( pOp->p5 & SQLITE_STOREP2 ){
pOut = &p->aMem[pOp->p2];
MemSetTypeFlag(pOut, MEM_Int);
pOut->u.i = res;
REGISTER_TRACE(pOp->p2, pOut);
}else if( res ){
pc = pOp->p2-1;
}
break;
}
/* Opcode: And P1 P2 P3 * *
**
** Take the logical AND of the values in registers P1 and P2 and
** write the result into register P3.
**
** If either P1 or P2 is 0 (false) then the result is 0 even if
** the other input is NULL. A NULL and true or two NULLs give
** a NULL output.
*/
/* Opcode: Or P1 P2 P3 * *
**
** Take the logical OR of the values in register P1 and P2 and
** store the answer in register P3.
**
** If either P1 or P2 is nonzero (true) then the result is 1 (true)
** even if the other input is NULL. A NULL and false or two NULLs
** give a NULL output.
*/
case OP_And: /* same as TK_AND, in1, in2, out3 */
case OP_Or: { /* same as TK_OR, in1, in2, out3 */
int v1, v2; /* 0==FALSE, 1==TRUE, 2==UNKNOWN or NULL */
if( pIn1->flags & MEM_Null ){
v1 = 2;
}else{
v1 = sqlite3VdbeIntValue(pIn1)!=0;
}
if( pIn2->flags & MEM_Null ){
v2 = 2;
}else{
v2 = sqlite3VdbeIntValue(pIn2)!=0;
}
if( pOp->opcode==OP_And ){
static const unsigned char and_logic[] = { 0, 0, 0, 0, 1, 2, 0, 2, 2 };
v1 = and_logic[v1*3+v2];
}else{
static const unsigned char or_logic[] = { 0, 1, 2, 1, 1, 1, 2, 1, 2 };
v1 = or_logic[v1*3+v2];
}
if( v1==2 ){
MemSetTypeFlag(pOut, MEM_Null);
}else{
pOut->u.i = v1;
MemSetTypeFlag(pOut, MEM_Int);
}
break;
}
/* Opcode: Not P1 * * * *
**
** Interpret the value in register P1 as a boolean value. Replace it
** with its complement. If the value in register P1 is NULL its value
** is unchanged.
*/
case OP_Not: { /* same as TK_NOT, in1 */
if( pIn1->flags & MEM_Null ) break; /* Do nothing to NULLs */
sqlite3VdbeMemIntegerify(pIn1);
pIn1->u.i = !pIn1->u.i;
assert( pIn1->flags&MEM_Int );
break;
}
/* Opcode: BitNot P1 * * * *
**
** Interpret the content of register P1 as an integer. Replace it
** with its ones-complement. If the value is originally NULL, leave
** it unchanged.
*/
case OP_BitNot: { /* same as TK_BITNOT, in1 */
if( pIn1->flags & MEM_Null ) break; /* Do nothing to NULLs */
sqlite3VdbeMemIntegerify(pIn1);
pIn1->u.i = ~pIn1->u.i;
assert( pIn1->flags&MEM_Int );
break;
}
/* Opcode: If P1 P2 P3 * *
**
** Jump to P2 if the value in register P1 is true. The value is
** is considered true if it is numeric and non-zero. If the value
** in P1 is NULL then take the jump if P3 is true.
*/
/* Opcode: IfNot P1 P2 P3 * *
**
** Jump to P2 if the value in register P1 is False. The value is
** is considered true if it has a numeric value of zero. If the value
** in P1 is NULL then take the jump if P3 is true.
*/
case OP_If: /* jump, in1 */
case OP_IfNot: { /* jump, in1 */
int c;
if( pIn1->flags & MEM_Null ){
c = pOp->p3;
}else{
#ifdef SQLITE_OMIT_FLOATING_POINT
c = sqlite3VdbeIntValue(pIn1);
#else
c = sqlite3VdbeRealValue(pIn1)!=0.0;
#endif
if( pOp->opcode==OP_IfNot ) c = !c;
}
if( c ){
pc = pOp->p2-1;
}
break;
}
/* Opcode: IsNull P1 P2 P3 * *
**
** Jump to P2 if the value in register P1 is NULL. If P3 is greater
** than zero, then check all values reg(P1), reg(P1+1),
** reg(P1+2), ..., reg(P1+P3-1).
*/
case OP_IsNull: { /* same as TK_ISNULL, jump, in1 */
int n = pOp->p3;
assert( pOp->p3==0 || pOp->p1>0 );
do{
if( (pIn1->flags & MEM_Null)!=0 ){
pc = pOp->p2 - 1;
break;
}
pIn1++;
}while( --n > 0 );
break;
}
/* Opcode: NotNull P1 P2 * * *
**
** Jump to P2 if the value in register P1 is not NULL.
*/
case OP_NotNull: { /* same as TK_NOTNULL, jump, in1 */
if( (pIn1->flags & MEM_Null)==0 ){
pc = pOp->p2 - 1;
}
break;
}
/* Opcode: SetNumColumns * P2 * * *
**
** This opcode sets the number of columns for the cursor opened by the
** following instruction to P2.
**
** An OP_SetNumColumns is only useful if it occurs immediately before
** one of the following opcodes:
**
** OpenRead
** OpenWrite
** OpenPseudo
**
** If the OP_Column opcode is to be executed on a cursor, then
** this opcode must be present immediately before the opcode that
** opens the cursor.
*/
case OP_SetNumColumns: {
break;
}
/* Opcode: Column P1 P2 P3 P4 *
**
** Interpret the data that cursor P1 points to as a structure built using
** the MakeRecord instruction. (See the MakeRecord opcode for additional
** information about the format of the data.) Extract the P2-th column
** from this record. If there are less that (P2+1)
** values in the record, extract a NULL.
**
** The value extracted is stored in register P3.
**
** If the KeyAsData opcode has previously executed on this cursor, then the
** field might be extracted from the key rather than the data.
**
** If the column contains fewer than P2 fields, then extract a NULL. Or,
** if the P4 argument is a P4_MEM use the value of the P4 argument as
** the result.
*/
case OP_Column: {
u32 payloadSize; /* Number of bytes in the record */
int p1 = pOp->p1; /* P1 value of the opcode */
int p2 = pOp->p2; /* column number to retrieve */
Cursor *pC = 0; /* The VDBE cursor */
char *zRec; /* Pointer to complete record-data */
BtCursor *pCrsr; /* The BTree cursor */
u32 *aType; /* aType[i] holds the numeric type of the i-th column */
u32 *aOffset; /* aOffset[i] is offset to start of data for i-th column */
u32 nField; /* number of fields in the record */
int len; /* The length of the serialized data for the column */
int i; /* Loop counter */
char *zData; /* Part of the record being decoded */
Mem *pDest; /* Where to write the extracted value */
Mem sMem; /* For storing the record being decoded */
sMem.flags = 0;
sMem.db = 0;
sMem.zMalloc = 0;
assert( p1<p->nCursor );
assert( pOp->p3>0 && pOp->p3<=p->nMem );
pDest = &p->aMem[pOp->p3];
MemSetTypeFlag(pDest, MEM_Null);
/* This block sets the variable payloadSize to be the total number of
** bytes in the record.
**
** zRec is set to be the complete text of the record if it is available.
** The complete record text is always available for pseudo-tables
** If the record is stored in a cursor, the complete record text
** might be available in the pC->aRow cache. Or it might not be.
** If the data is unavailable, zRec is set to NULL.
**
** We also compute the number of columns in the record. For cursors,
** the number of columns is stored in the Cursor.nField element.
*/
pC = p->apCsr[p1];
assert( pC!=0 );
#ifndef SQLITE_OMIT_VIRTUALTABLE
assert( pC->pVtabCursor==0 );
#endif
if( pC->pCursor!=0 ){
/* The record is stored in a B-Tree */
rc = sqlite3VdbeCursorMoveto(pC);
if( rc ) goto abort_due_to_error;
zRec = 0;
pCrsr = pC->pCursor;
if( pC->nullRow ){
payloadSize = 0;
}else if( pC->cacheStatus==p->cacheCtr ){
payloadSize = pC->payloadSize;
zRec = (char*)pC->aRow;
}else if( pC->isIndex ){
i64 payloadSize64;
sqlite3BtreeKeySize(pCrsr, &payloadSize64);
payloadSize = payloadSize64;
}else{
sqlite3BtreeDataSize(pCrsr, &payloadSize);
}
nField = pC->nField;
}else{
assert( pC->pseudoTable );
/* The record is the sole entry of a pseudo-table */
payloadSize = pC->nData;
zRec = pC->pData;
pC->cacheStatus = CACHE_STALE;
assert( payloadSize==0 || zRec!=0 );
nField = pC->nField;
pCrsr = 0;
}
/* If payloadSize is 0, then just store a NULL */
if( payloadSize==0 ){
assert( pDest->flags&MEM_Null );
goto op_column_out;
}
if( payloadSize>db->aLimit[SQLITE_LIMIT_LENGTH] ){
goto too_big;
}
assert( p2<nField );
/* Read and parse the table header. Store the results of the parse
** into the record header cache fields of the cursor.
*/
aType = pC->aType;
if( pC->cacheStatus==p->cacheCtr ){
aOffset = pC->aOffset;
}else{
u8 *zIdx; /* Index into header */
u8 *zEndHdr; /* Pointer to first byte after the header */
u32 offset; /* Offset into the data */
int szHdrSz; /* Size of the header size field at start of record */
int avail; /* Number of bytes of available data */
assert(aType);
pC->aOffset = aOffset = &aType[nField];
pC->payloadSize = payloadSize;
pC->cacheStatus = p->cacheCtr;
/* Figure out how many bytes are in the header */
if( zRec ){
zData = zRec;
}else{
if( pC->isIndex ){
zData = (char*)sqlite3BtreeKeyFetch(pCrsr, &avail);
}else{
zData = (char*)sqlite3BtreeDataFetch(pCrsr, &avail);
}
/* If KeyFetch()/DataFetch() managed to get the entire payload,
** save the payload in the pC->aRow cache. That will save us from
** having to make additional calls to fetch the content portion of
** the record.
*/
if( avail>=payloadSize ){
zRec = zData;
pC->aRow = (u8*)zData;
}else{
pC->aRow = 0;
}
}
/* The following assert is true in all cases accept when
** the database file has been corrupted externally.
** assert( zRec!=0 || avail>=payloadSize || avail>=9 ); */
szHdrSz = GetVarint((u8*)zData, offset);
/* The KeyFetch() or DataFetch() above are fast and will get the entire
** record header in most cases. But they will fail to get the complete
** record header if the record header does not fit on a single page
** in the B-Tree. When that happens, use sqlite3VdbeMemFromBtree() to
** acquire the complete header text.
*/
if( !zRec && avail<offset ){
sMem.flags = 0;
sMem.db = 0;
rc = sqlite3VdbeMemFromBtree(pCrsr, 0, offset, pC->isIndex, &sMem);
if( rc!=SQLITE_OK ){
goto op_column_out;
}
zData = sMem.z;
}
zEndHdr = (u8 *)&zData[offset];
zIdx = (u8 *)&zData[szHdrSz];
/* Scan the header and use it to fill in the aType[] and aOffset[]
** arrays. aType[i] will contain the type integer for the i-th
** column and aOffset[i] will contain the offset from the beginning
** of the record to the start of the data for the i-th column
*/
for(i=0; i<nField; i++){
if( zIdx<zEndHdr ){
aOffset[i] = offset;
zIdx += GetVarint(zIdx, aType[i]);
offset += sqlite3VdbeSerialTypeLen(aType[i]);
}else{
/* If i is less that nField, then there are less fields in this
** record than SetNumColumns indicated there are columns in the
** table. Set the offset for any extra columns not present in
** the record to 0. This tells code below to store a NULL
** instead of deserializing a value from the record.
*/
aOffset[i] = 0;
}
}
sqlite3VdbeMemRelease(&sMem);
sMem.flags = MEM_Null;
/* If we have read more header data than was contained in the header,
** or if the end of the last field appears to be past the end of the
** record, then we must be dealing with a corrupt database.
*/
if( zIdx>zEndHdr || offset>payloadSize ){
rc = SQLITE_CORRUPT_BKPT;
goto op_column_out;
}
}
/* Get the column information. If aOffset[p2] is non-zero, then
** deserialize the value from the record. If aOffset[p2] is zero,
** then there are not enough fields in the record to satisfy the
** request. In this case, set the value NULL or to P4 if P4 is
** a pointer to a Mem object.
*/
if( aOffset[p2] ){
assert( rc==SQLITE_OK );
if( zRec ){
if( pDest->flags&MEM_Dyn ){
sqlite3VdbeSerialGet((u8 *)&zRec[aOffset[p2]], aType[p2], &sMem);
sMem.db = db;
rc = sqlite3VdbeMemCopy(pDest, &sMem);
assert( !(sMem.flags&MEM_Dyn) );
if( rc!=SQLITE_OK ){
goto op_column_out;
}
}else{
sqlite3VdbeSerialGet((u8 *)&zRec[aOffset[p2]], aType[p2], pDest);
}
}else{
len = sqlite3VdbeSerialTypeLen(aType[p2]);
sqlite3VdbeMemMove(&sMem, pDest);
rc = sqlite3VdbeMemFromBtree(pCrsr, aOffset[p2], len, pC->isIndex, &sMem);
if( rc!=SQLITE_OK ){
goto op_column_out;
}
zData = sMem.z;
sqlite3VdbeSerialGet((u8*)zData, aType[p2], pDest);
}
pDest->enc = encoding;
}else{
if( pOp->p4type==P4_MEM ){
sqlite3VdbeMemShallowCopy(pDest, pOp->p4.pMem, MEM_Static);
}else{
assert( pDest->flags&MEM_Null );
}
}
/* If we dynamically allocated space to hold the data (in the
** sqlite3VdbeMemFromBtree() call above) then transfer control of that
** dynamically allocated space over to the pDest structure.
** This prevents a memory copy.
*/
if( sMem.zMalloc ){
assert( sMem.z==sMem.zMalloc );
assert( !(pDest->flags & MEM_Dyn) );
assert( !(pDest->flags & (MEM_Blob|MEM_Str)) || pDest->z==sMem.z );
pDest->flags &= ~(MEM_Ephem|MEM_Static);
pDest->flags |= MEM_Term;
pDest->z = sMem.z;
pDest->zMalloc = sMem.zMalloc;
}
rc = sqlite3VdbeMemMakeWriteable(pDest);
op_column_out:
UPDATE_MAX_BLOBSIZE(pDest);
REGISTER_TRACE(pOp->p3, pDest);
break;
}
/* Opcode: MakeRecord P1 P2 P3 P4 *
**
** Convert P2 registers beginning with P1 into a single entry
** suitable for use as a data record in a database table or as a key
** in an index. The details of the format are irrelavant as long as
** the OP_Column opcode can decode the record later.
** Refer to source code comments for the details of the record
** format.
**
** P4 may be a string that is P1 characters long. The nth character of the
** string indicates the column affinity that should be used for the nth
** field of the index key.
**
** The mapping from character to affinity is given by the SQLITE_AFF_
** macros defined in sqliteInt.h.
**
** If P4 is NULL then all index fields have the affinity NONE.
*/
case OP_MakeRecord: {
/* Assuming the record contains N fields, the record format looks
** like this:
**
** ------------------------------------------------------------------------
** | hdr-size | type 0 | type 1 | ... | type N-1 | data0 | ... | data N-1 |
** ------------------------------------------------------------------------
**
** Data(0) is taken from register P1. Data(1) comes from register P1+1
** and so froth.
**
** Each type field is a varint representing the serial type of the
** corresponding data element (see sqlite3VdbeSerialType()). The
** hdr-size field is also a varint which is the offset from the beginning
** of the record to data0.
*/
u8 *zNewRecord; /* A buffer to hold the data for the new record */
Mem *pRec; /* The new record */
u64 nData = 0; /* Number of bytes of data space */
int nHdr = 0; /* Number of bytes of header space */
u64 nByte = 0; /* Data space required for this record */
int nZero = 0; /* Number of zero bytes at the end of the record */
int nVarint; /* Number of bytes in a varint */
u32 serial_type; /* Type field */
Mem *pData0; /* First field to be combined into the record */
Mem *pLast; /* Last field of the record */
int nField; /* Number of fields in the record */
char *zAffinity; /* The affinity string for the record */
int file_format; /* File format to use for encoding */
int i; /* Space used in zNewRecord[] */
nField = pOp->p1;
zAffinity = pOp->p4.z;
assert( nField>0 && pOp->p2>0 && pOp->p2+nField<=p->nMem );
pData0 = &p->aMem[nField];
nField = pOp->p2;
pLast = &pData0[nField-1];
file_format = p->minWriteFileFormat;
/* Loop through the elements that will make up the record to figure
** out how much space is required for the new record.
*/
for(pRec=pData0; pRec<=pLast; pRec++){
int len;
if( zAffinity ){
applyAffinity(pRec, zAffinity[pRec-pData0], encoding);
}
if( pRec->flags&MEM_Zero && pRec->n>0 ){
sqlite3VdbeMemExpandBlob(pRec);
}
serial_type = sqlite3VdbeSerialType(pRec, file_format);
len = sqlite3VdbeSerialTypeLen(serial_type);
nData += len;
nHdr += sqlite3VarintLen(serial_type);
if( pRec->flags & MEM_Zero ){
/* Only pure zero-filled BLOBs can be input to this Opcode.
** We do not allow blobs with a prefix and a zero-filled tail. */
nZero += pRec->u.i;
}else if( len ){
nZero = 0;
}
}
/* Add the initial header varint and total the size */
nHdr += nVarint = sqlite3VarintLen(nHdr);
if( nVarint<sqlite3VarintLen(nHdr) ){
nHdr++;
}
nByte = nHdr+nData-nZero;
if( nByte>db->aLimit[SQLITE_LIMIT_LENGTH] ){
goto too_big;
}
/* Make sure the output register has a buffer large enough to store
** the new record. The output register (pOp->p3) is not allowed to
** be one of the input registers (because the following call to
** sqlite3VdbeMemGrow() could clobber the value before it is used).
*/
assert( pOp->p3<pOp->p1 || pOp->p3>=pOp->p1+pOp->p2 );
pOut = &p->aMem[pOp->p3];
if( sqlite3VdbeMemGrow(pOut, nByte, 0) ){
goto no_mem;
}
zNewRecord = (u8 *)pOut->z;
/* Write the record */
i = sqlite3PutVarint32(zNewRecord, nHdr);
for(pRec=pData0; pRec<=pLast; pRec++){
serial_type = sqlite3VdbeSerialType(pRec, file_format);
i += sqlite3PutVarint32(&zNewRecord[i], serial_type); /* serial type */
}
for(pRec=pData0; pRec<=pLast; pRec++){ /* serial data */
i += sqlite3VdbeSerialPut(&zNewRecord[i], nByte-i, pRec, file_format);
}
assert( i==nByte );
assert( pOp->p3>0 && pOp->p3<=p->nMem );
pOut->n = nByte;
pOut->flags = MEM_Blob | MEM_Dyn;
pOut->xDel = 0;
if( nZero ){
pOut->u.i = nZero;
pOut->flags |= MEM_Zero;
}
pOut->enc = SQLITE_UTF8; /* In case the blob is ever converted to text */
REGISTER_TRACE(pOp->p3, pOut);
UPDATE_MAX_BLOBSIZE(pOut);
break;
}
/* Opcode: Statement P1 * * * *
**
** Begin an individual statement transaction which is part of a larger
** BEGIN..COMMIT transaction. This is needed so that the statement
** can be rolled back after an error without having to roll back the
** entire transaction. The statement transaction will automatically
** commit when the VDBE halts.
**
** The statement is begun on the database file with index P1. The main
** database file has an index of 0 and the file used for temporary tables
** has an index of 1.
*/
case OP_Statement: {
if( db->autoCommit==0 || db->activeVdbeCnt>1 ){
int i = pOp->p1;
Btree *pBt;
assert( i>=0 && i<db->nDb );
assert( db->aDb[i].pBt!=0 );
pBt = db->aDb[i].pBt;
assert( sqlite3BtreeIsInTrans(pBt) );
assert( (p->btreeMask & (1<<i))!=0 );
if( !sqlite3BtreeIsInStmt(pBt) ){
rc = sqlite3BtreeBeginStmt(pBt);
p->openedStatement = 1;
}
}
break;
}
/* Opcode: AutoCommit P1 P2 * * *
**
** Set the database auto-commit flag to P1 (1 or 0). If P2 is true, roll
** back any currently active btree transactions. If there are any active
** VMs (apart from this one), then the COMMIT or ROLLBACK statement fails.
**
** This instruction causes the VM to halt.
*/
case OP_AutoCommit: {
u8 i = pOp->p1;
u8 rollback = pOp->p2;
assert( i==1 || i==0 );
assert( i==1 || rollback==0 );
assert( db->activeVdbeCnt>0 ); /* At least this one VM is active */
if( db->activeVdbeCnt>1 && i && !db->autoCommit ){
/* If this instruction implements a COMMIT or ROLLBACK, other VMs are
** still running, and a transaction is active, return an error indicating
** that the other VMs must complete first.
*/
sqlite3SetString(&p->zErrMsg, "cannot ", rollback?"rollback":"commit",
" transaction - SQL statements in progress", (char*)0);
rc = SQLITE_ERROR;
}else if( i!=db->autoCommit ){
if( pOp->p2 ){
assert( i==1 );
sqlite3RollbackAll(db);
db->autoCommit = 1;
}else{
db->autoCommit = i;
if( sqlite3VdbeHalt(p)==SQLITE_BUSY ){
p->pc = pc;
db->autoCommit = 1-i;
p->rc = rc = SQLITE_BUSY;
goto vdbe_return;
}
}
if( p->rc==SQLITE_OK ){
rc = SQLITE_DONE;
}else{
rc = SQLITE_ERROR;
}
goto vdbe_return;
}else{
sqlite3SetString(&p->zErrMsg,
(!i)?"cannot start a transaction within a transaction":(
(rollback)?"cannot rollback - no transaction is active":
"cannot commit - no transaction is active"), (char*)0);
rc = SQLITE_ERROR;
}
break;
}
/* Opcode: Transaction P1 P2 * * *
**
** Begin a transaction. The transaction ends when a Commit or Rollback
** opcode is encountered. Depending on the ON CONFLICT setting, the
** transaction might also be rolled back if an error is encountered.
**
** P1 is the index of the database file on which the transaction is
** started. Index 0 is the main database file and index 1 is the
** file used for temporary tables. Indices of 2 or more are used for
** attached databases.
**
** If P2 is non-zero, then a write-transaction is started. A RESERVED lock is
** obtained on the database file when a write-transaction is started. No
** other process can start another write transaction while this transaction is
** underway. Starting a write transaction also creates a rollback journal. A
** write transaction must be started before any changes can be made to the
** database. If P2 is 2 or greater then an EXCLUSIVE lock is also obtained
** on the file.
**
** If P2 is zero, then a read-lock is obtained on the database file.
*/
case OP_Transaction: {
int i = pOp->p1;
Btree *pBt;
assert( i>=0 && i<db->nDb );
assert( (p->btreeMask & (1<<i))!=0 );
pBt = db->aDb[i].pBt;
if( pBt ){
rc = sqlite3BtreeBeginTrans(pBt, pOp->p2);
if( rc==SQLITE_BUSY ){
p->pc = pc;
p->rc = rc = SQLITE_BUSY;
goto vdbe_return;
}
if( rc!=SQLITE_OK && rc!=SQLITE_READONLY /* && rc!=SQLITE_BUSY */ ){
goto abort_due_to_error;
}
}
break;
}
/* Opcode: ReadCookie P1 P2 P3 * *
**
** Read cookie number P3 from database P1 and write it into register P2.
** P3==0 is the schema version. P3==1 is the database format.
** P3==2 is the recommended pager cache size, and so forth. P1==0 is
** the main database file and P1==1 is the database file used to store
** temporary tables.
**
** If P1 is negative, then this is a request to read the size of a
** databases free-list. P3 must be set to 1 in this case. The actual
** database accessed is ((P1+1)*-1). For example, a P1 parameter of -1
** corresponds to database 0 ("main"), a P1 of -2 is database 1 ("temp").
**
** There must be a read-lock on the database (either a transaction
** must be started or there must be an open cursor) before
** executing this instruction.
*/
case OP_ReadCookie: { /* out2-prerelease */
int iMeta;
int iDb = pOp->p1;
int iCookie = pOp->p3;
assert( pOp->p3<SQLITE_N_BTREE_META );
if( iDb<0 ){
iDb = (-1*(iDb+1));
iCookie *= -1;
}
assert( iDb>=0 && iDb<db->nDb );
assert( db->aDb[iDb].pBt!=0 );
assert( (p->btreeMask & (1<<iDb))!=0 );
/* The indexing of meta values at the schema layer is off by one from
** the indexing in the btree layer. The btree considers meta[0] to
** be the number of free pages in the database (a read-only value)
** and meta[1] to be the schema cookie. The schema layer considers
** meta[1] to be the schema cookie. So we have to shift the index
** by one in the following statement.
*/
rc = sqlite3BtreeGetMeta(db->aDb[iDb].pBt, 1 + iCookie, (u32 *)&iMeta);
pOut->u.i = iMeta;
MemSetTypeFlag(pOut, MEM_Int);
break;
}
/* Opcode: SetCookie P1 P2 P3 * *
**
** Write the content of register P3 (interpreted as an integer)
** into cookie number P2 of database P1.
** P2==0 is the schema version. P2==1 is the database format.
** P2==2 is the recommended pager cache size, and so forth. P1==0 is
** the main database file and P1==1 is the database file used to store
** temporary tables.
**
** A transaction must be started before executing this opcode.
*/
case OP_SetCookie: { /* in3 */
Db *pDb;
assert( pOp->p2<SQLITE_N_BTREE_META );
assert( pOp->p1>=0 && pOp->p1<db->nDb );
assert( (p->btreeMask & (1<<pOp->p1))!=0 );
pDb = &db->aDb[pOp->p1];
assert( pDb->pBt!=0 );
sqlite3VdbeMemIntegerify(pIn3);
/* See note about index shifting on OP_ReadCookie */
rc = sqlite3BtreeUpdateMeta(pDb->pBt, 1+pOp->p2, (int)pIn3->u.i);
if( pOp->p2==0 ){
/* When the schema cookie changes, record the new cookie internally */