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** 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.
** Header file for the Virtual DataBase Engine (VDBE)
** This header defines the interface to the virtual database engine
** or VDBE. The VDBE implements an abstract machine that runs a
** simple program to access and modify the underlying database.
#ifndef _SQLITE_VDBE_H_
#define _SQLITE_VDBE_H_
#include <stdio.h>
** A single VDBE is an opaque structure named "Vdbe". Only routines
** in the source file sqliteVdbe.c are allowed to see the insides
** of this structure.
typedef struct Vdbe Vdbe;
** The names of the following types declared in vdbeInt.h are required
** for the VdbeOp definition.
typedef struct VdbeFunc VdbeFunc;
typedef struct Mem Mem;
typedef struct SubProgram SubProgram;
** A single instruction of the virtual machine has an opcode
** and as many as three operands. The instruction is recorded
** as an instance of the following structure:
struct VdbeOp {
u8 opcode; /* What operation to perform */
signed char p4type; /* One of the P4_xxx constants for p4 */
u8 opflags; /* Mask of the OPFLG_* flags in opcodes.h */
u8 p5; /* Fifth parameter is an unsigned character */
int p1; /* First operand */
int p2; /* Second parameter (often the jump destination) */
int p3; /* The third parameter */
union { /* fourth parameter */
int i; /* Integer value if p4type==P4_INT32 */
void *p; /* Generic pointer */
char *z; /* Pointer to data for string (char array) types */
i64 *pI64; /* Used when p4type is P4_INT64 */
double *pReal; /* Used when p4type is P4_REAL */
FuncDef *pFunc; /* Used when p4type is P4_FUNCDEF */
VdbeFunc *pVdbeFunc; /* Used when p4type is P4_VDBEFUNC */
CollSeq *pColl; /* Used when p4type is P4_COLLSEQ */
Mem *pMem; /* Used when p4type is P4_MEM */
VTable *pVtab; /* Used when p4type is P4_VTAB */
KeyInfo *pKeyInfo; /* Used when p4type is P4_KEYINFO */
int *ai; /* Used when p4type is P4_INTARRAY */
SubProgram *pProgram; /* Used when p4type is P4_SUBPROGRAM */
} p4;
char *zComment; /* Comment to improve readability */
int cnt; /* Number of times this instruction was executed */
u64 cycles; /* Total time spent executing this instruction */
typedef struct VdbeOp VdbeOp;
** A sub-routine used to implement a trigger program.
struct SubProgram {
VdbeOp *aOp; /* Array of opcodes for sub-program */
int nOp; /* Elements in aOp[] */
int nMem; /* Number of memory cells required */
int nCsr; /* Number of cursors required */
void *token; /* id that may be used to recursive triggers */
SubProgram *pNext; /* Next sub-program already visited */
** A smaller version of VdbeOp used for the VdbeAddOpList() function because
** it takes up less space.
struct VdbeOpList {
u8 opcode; /* What operation to perform */
signed char p1; /* First operand */
signed char p2; /* Second parameter (often the jump destination) */
signed char p3; /* Third parameter */
typedef struct VdbeOpList VdbeOpList;
** Allowed values of VdbeOp.p4type
#define P4_NOTUSED 0 /* The P4 parameter is not used */
#define P4_DYNAMIC (-1) /* Pointer to a string obtained from sqliteMalloc() */
#define P4_STATIC (-2) /* Pointer to a static string */
#define P4_COLLSEQ (-4) /* P4 is a pointer to a CollSeq structure */
#define P4_FUNCDEF (-5) /* P4 is a pointer to a FuncDef structure */
#define P4_KEYINFO (-6) /* P4 is a pointer to a KeyInfo structure */
#define P4_VDBEFUNC (-7) /* P4 is a pointer to a VdbeFunc structure */
#define P4_MEM (-8) /* P4 is a pointer to a Mem* structure */
#define P4_TRANSIENT 0 /* P4 is a pointer to a transient string */
#define P4_VTAB (-10) /* P4 is a pointer to an sqlite3_vtab structure */
#define P4_MPRINTF (-11) /* P4 is a string obtained from sqlite3_mprintf() */
#define P4_REAL (-12) /* P4 is a 64-bit floating point value */
#define P4_INT64 (-13) /* P4 is a 64-bit signed integer */
#define P4_INT32 (-14) /* P4 is a 32-bit signed integer */
#define P4_INTARRAY (-15) /* P4 is a vector of 32-bit integers */
#define P4_SUBPROGRAM (-18) /* P4 is a pointer to a SubProgram structure */
/* When adding a P4 argument using P4_KEYINFO, a copy of the KeyInfo structure
** is made. That copy is freed when the Vdbe is finalized. But if the
** argument is P4_KEYINFO_HANDOFF, the passed in pointer is used. It still
** gets freed when the Vdbe is finalized so it still should be obtained
** from a single sqliteMalloc(). But no copy is made and the calling
** function should *not* try to free the KeyInfo.
#define P4_KEYINFO_HANDOFF (-16)
#define P4_KEYINFO_STATIC (-17)
** The Vdbe.aColName array contains 5n Mem structures, where n is the
** number of columns of data returned by the statement.
#define COLNAME_NAME 0
# define COLNAME_N 5 /* Number of COLNAME_xxx symbols */
# define COLNAME_N 1 /* Store only the name */
# else
# define COLNAME_N 2 /* Store the name and decltype */
# endif
** The following macro converts a relative address in the p2 field
** of a VdbeOp structure into a negative number so that
** sqlite3VdbeAddOpList() knows that the address is relative. Calling
** the macro again restores the address.
#define ADDR(X) (-1-(X))
** The makefile scans the vdbe.c source file and creates the "opcodes.h"
** header file that defines a number for each opcode used by the VDBE.
#include "opcodes.h"
** Prototypes for the VDBE interface. See comments on the implementation
** for a description of what each of these routines does.
Vdbe *sqlite3VdbeCreate(sqlite3*);
int sqlite3VdbeAddOp0(Vdbe*,int);
int sqlite3VdbeAddOp1(Vdbe*,int,int);
int sqlite3VdbeAddOp2(Vdbe*,int,int,int);
int sqlite3VdbeAddOp3(Vdbe*,int,int,int,int);
int sqlite3VdbeAddOp4(Vdbe*,int,int,int,int,const char *zP4,int);
int sqlite3VdbeAddOp4Int(Vdbe*,int,int,int,int,int);
int sqlite3VdbeAddOpList(Vdbe*, int nOp, VdbeOpList const *aOp);
void sqlite3VdbeChangeP1(Vdbe*, int addr, int P1);
void sqlite3VdbeChangeP2(Vdbe*, int addr, int P2);
void sqlite3VdbeChangeP3(Vdbe*, int addr, int P3);
void sqlite3VdbeChangeP5(Vdbe*, u8 P5);
void sqlite3VdbeJumpHere(Vdbe*, int addr);
void sqlite3VdbeChangeToNoop(Vdbe*, int addr, int N);
void sqlite3VdbeChangeP4(Vdbe*, int addr, const char *zP4, int N);
void sqlite3VdbeUsesBtree(Vdbe*, int);
VdbeOp *sqlite3VdbeGetOp(Vdbe*, int);
int sqlite3VdbeMakeLabel(Vdbe*);
void sqlite3VdbeRunOnlyOnce(Vdbe*);
void sqlite3VdbeDelete(Vdbe*);
void sqlite3VdbeDeleteObject(sqlite3*,Vdbe*);
void sqlite3VdbeMakeReady(Vdbe*,int,int,int,int,int,int);
int sqlite3VdbeFinalize(Vdbe*);
void sqlite3VdbeResolveLabel(Vdbe*, int);
int sqlite3VdbeCurrentAddr(Vdbe*);
int sqlite3VdbeAssertMayAbort(Vdbe *, int);
void sqlite3VdbeTrace(Vdbe*,FILE*);
void sqlite3VdbeResetStepResult(Vdbe*);
int sqlite3VdbeReset(Vdbe*);
void sqlite3VdbeSetNumCols(Vdbe*,int);
int sqlite3VdbeSetColName(Vdbe*, int, int, const char *, void(*)(void*));
void sqlite3VdbeCountChanges(Vdbe*);
sqlite3 *sqlite3VdbeDb(Vdbe*);
void sqlite3VdbeSetSql(Vdbe*, const char *z, int n, int);
void sqlite3VdbeSwap(Vdbe*,Vdbe*);
VdbeOp *sqlite3VdbeTakeOpArray(Vdbe*, int*, int*);
sqlite3_value *sqlite3VdbeGetValue(Vdbe*, int, u8);
void sqlite3VdbeSetVarmask(Vdbe*, int);
char *sqlite3VdbeExpandSql(Vdbe*, const char*);
UnpackedRecord *sqlite3VdbeRecordUnpack(KeyInfo*,int,const void*,char*,int);
void sqlite3VdbeDeleteUnpackedRecord(UnpackedRecord*);
int sqlite3VdbeRecordCompare(int,const void*,UnpackedRecord*);
void sqlite3VdbeLinkSubProgram(Vdbe *, SubProgram *);
#ifndef NDEBUG
void sqlite3VdbeComment(Vdbe*, const char*, ...);
# define VdbeComment(X) sqlite3VdbeComment X
void sqlite3VdbeNoopComment(Vdbe*, const char*, ...);
# define VdbeNoopComment(X) sqlite3VdbeNoopComment X
# define VdbeComment(X)
# define VdbeNoopComment(X)