4 ** The author disclaims copyright to this source code. In place of
5 ** a legal notice, here is a blessing:
7 ** May you do good and not evil.
8 ** May you find forgiveness for yourself and forgive others.
9 ** May you share freely, never taking more than you give.
11 *************************************************************************
12 ** Header file for the Virtual DataBase Engine (VDBE)
14 ** This header defines the interface to the virtual database engine
15 ** or VDBE. The VDBE implements an abstract machine that runs a
16 ** simple program to access and modify the underlying database.
18 ** $Id: vdbe.h,v 1.135 2008/08/01 20:10:08 drh Exp $
20 #ifndef _SQLITE_VDBE_H_
21 #define _SQLITE_VDBE_H_
25 ** A single VDBE is an opaque structure named "Vdbe". Only routines
26 ** in the source file sqliteVdbe.c are allowed to see the insides
29 typedef struct Vdbe Vdbe;
32 ** The names of the following types declared in vdbeInt.h are required
33 ** for the VdbeOp definition.
35 typedef struct VdbeFunc VdbeFunc;
36 typedef struct Mem Mem;
37 typedef struct UnpackedRecord UnpackedRecord;
40 ** A single instruction of the virtual machine has an opcode
41 ** and as many as three operands. The instruction is recorded
42 ** as an instance of the following structure:
45 u8 opcode; /* What operation to perform */
46 signed char p4type; /* One of the P4_xxx constants for p4 */
47 u8 opflags; /* Not currently used */
48 u8 p5; /* Fifth parameter is an unsigned character */
49 int p1; /* First operand */
50 int p2; /* Second parameter (often the jump destination) */
51 int p3; /* The third parameter */
52 union { /* forth parameter */
53 int i; /* Integer value if p4type==P4_INT32 */
54 void *p; /* Generic pointer */
55 char *z; /* Pointer to data for string (char array) types */
56 i64 *pI64; /* Used when p4type is P4_INT64 */
57 double *pReal; /* Used when p4type is P4_REAL */
58 FuncDef *pFunc; /* Used when p4type is P4_FUNCDEF */
59 VdbeFunc *pVdbeFunc; /* Used when p4type is P4_VDBEFUNC */
60 CollSeq *pColl; /* Used when p4type is P4_COLLSEQ */
61 Mem *pMem; /* Used when p4type is P4_MEM */
62 sqlite3_vtab *pVtab; /* Used when p4type is P4_VTAB */
63 KeyInfo *pKeyInfo; /* Used when p4type is P4_KEYINFO */
64 int *ai; /* Used when p4type is P4_INTARRAY */
67 char *zComment; /* Comment to improve readability */
70 int cnt; /* Number of times this instruction was executed */
71 u64 cycles; /* Total time spent executing this instruction */
74 typedef struct VdbeOp VdbeOp;
77 ** A smaller version of VdbeOp used for the VdbeAddOpList() function because
78 ** it takes up less space.
81 u8 opcode; /* What operation to perform */
82 signed char p1; /* First operand */
83 signed char p2; /* Second parameter (often the jump destination) */
84 signed char p3; /* Third parameter */
86 typedef struct VdbeOpList VdbeOpList;
89 ** Allowed values of VdbeOp.p3type
91 #define P4_NOTUSED 0 /* The P4 parameter is not used */
92 #define P4_DYNAMIC (-1) /* Pointer to a string obtained from sqliteMalloc() */
93 #define P4_STATIC (-2) /* Pointer to a static string */
94 #define P4_COLLSEQ (-4) /* P4 is a pointer to a CollSeq structure */
95 #define P4_FUNCDEF (-5) /* P4 is a pointer to a FuncDef structure */
96 #define P4_KEYINFO (-6) /* P4 is a pointer to a KeyInfo structure */
97 #define P4_VDBEFUNC (-7) /* P4 is a pointer to a VdbeFunc structure */
98 #define P4_MEM (-8) /* P4 is a pointer to a Mem* structure */
99 #define P4_TRANSIENT (-9) /* P4 is a pointer to a transient string */
100 #define P4_VTAB (-10) /* P4 is a pointer to an sqlite3_vtab structure */
101 #define P4_MPRINTF (-11) /* P4 is a string obtained from sqlite3_mprintf() */
102 #define P4_REAL (-12) /* P4 is a 64-bit floating point value */
103 #define P4_INT64 (-13) /* P4 is a 64-bit signed integer */
104 #define P4_INT32 (-14) /* P4 is a 32-bit signed integer */
105 #define P4_INTARRAY (-15) /* P4 is a vector of 32-bit integers */
107 /* When adding a P4 argument using P4_KEYINFO, a copy of the KeyInfo structure
108 ** is made. That copy is freed when the Vdbe is finalized. But if the
109 ** argument is P4_KEYINFO_HANDOFF, the passed in pointer is used. It still
110 ** gets freed when the Vdbe is finalized so it still should be obtained
111 ** from a single sqliteMalloc(). But no copy is made and the calling
112 ** function should *not* try to free the KeyInfo.
114 #define P4_KEYINFO_HANDOFF (-16)
115 #define P4_KEYINFO_STATIC (-17)
118 ** The Vdbe.aColName array contains 5n Mem structures, where n is the
119 ** number of columns of data returned by the statement.
121 #define COLNAME_NAME 0
122 #define COLNAME_DECLTYPE 1
123 #define COLNAME_DATABASE 2
124 #define COLNAME_TABLE 3
125 #define COLNAME_COLUMN 4
126 #ifdef SQLITE_ENABLE_COLUMN_METADATA
127 # define COLNAME_N 5 /* Number of COLNAME_xxx symbols */
129 # ifdef SQLITE_OMIT_DECLTYPE
130 # define COLNAME_N 1 /* Store only the name */
132 # define COLNAME_N 2 /* Store the name and decltype */
137 ** The following macro converts a relative address in the p2 field
138 ** of a VdbeOp structure into a negative number so that
139 ** sqlite3VdbeAddOpList() knows that the address is relative. Calling
140 ** the macro again restores the address.
142 #define ADDR(X) (-1-(X))
145 ** The makefile scans the vdbe.c source file and creates the "opcodes.h"
146 ** header file that defines a number for each opcode used by the VDBE.
151 ** Prototypes for the VDBE interface. See comments on the implementation
152 ** for a description of what each of these routines does.
154 Vdbe *sqlite3VdbeCreate(sqlite3*);
155 int sqlite3VdbeAddOp0(Vdbe*,int);
156 int sqlite3VdbeAddOp1(Vdbe*,int,int);
157 int sqlite3VdbeAddOp2(Vdbe*,int,int,int);
158 int sqlite3VdbeAddOp3(Vdbe*,int,int,int,int);
159 int sqlite3VdbeAddOp4(Vdbe*,int,int,int,int,const char *zP4,int);
160 int sqlite3VdbeAddOpList(Vdbe*, int nOp, VdbeOpList const *aOp);
161 void sqlite3VdbeChangeP1(Vdbe*, int addr, int P1);
162 void sqlite3VdbeChangeP2(Vdbe*, int addr, int P2);
163 void sqlite3VdbeChangeP3(Vdbe*, int addr, int P3);
164 void sqlite3VdbeChangeP5(Vdbe*, u8 P5);
165 void sqlite3VdbeJumpHere(Vdbe*, int addr);
166 void sqlite3VdbeChangeToNoop(Vdbe*, int addr, int N);
167 void sqlite3VdbeChangeP4(Vdbe*, int addr, const char *zP4, int N);
168 void sqlite3VdbeUsesBtree(Vdbe*, int);
169 VdbeOp *sqlite3VdbeGetOp(Vdbe*, int);
170 int sqlite3VdbeMakeLabel(Vdbe*);
171 void sqlite3VdbeDelete(Vdbe*);
172 void sqlite3VdbeMakeReady(Vdbe*,int,int,int,int);
173 int sqlite3VdbeFinalize(Vdbe*);
174 void sqlite3VdbeResolveLabel(Vdbe*, int);
175 int sqlite3VdbeCurrentAddr(Vdbe*);
177 void sqlite3VdbeTrace(Vdbe*,FILE*);
179 void sqlite3VdbeResetStepResult(Vdbe*);
180 int sqlite3VdbeReset(Vdbe*);
181 void sqlite3VdbeSetNumCols(Vdbe*,int);
182 int sqlite3VdbeSetColName(Vdbe*, int, int, const char *, int);
183 void sqlite3VdbeCountChanges(Vdbe*);
184 sqlite3 *sqlite3VdbeDb(Vdbe*);
185 void sqlite3VdbeSetSql(Vdbe*, const char *z, int n);
186 void sqlite3VdbeSwap(Vdbe*,Vdbe*);
188 #ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
189 int sqlite3VdbeReleaseMemory(int);
191 UnpackedRecord *sqlite3VdbeRecordUnpack(KeyInfo*,int,const void*,void*,int);
192 void sqlite3VdbeDeleteUnpackedRecord(UnpackedRecord*);
193 int sqlite3VdbeRecordCompare(int,const void*,UnpackedRecord*);
197 void sqlite3VdbeComment(Vdbe*, const char*, ...);
198 # define VdbeComment(X) sqlite3VdbeComment X
199 void sqlite3VdbeNoopComment(Vdbe*, const char*, ...);
200 # define VdbeNoopComment(X) sqlite3VdbeNoopComment X
202 # define VdbeComment(X)
203 # define VdbeNoopComment(X)