1/*
2** 2001 September 15
3**
4** The author disclaims copyright to this source code.  In place of
5** a legal notice, here is a blessing:
6**
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.
10**
11*************************************************************************
12** Header file for the Virtual DataBase Engine (VDBE)
13**
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.
17*/
18#ifndef _SQLITE_VDBE_H_
19#define _SQLITE_VDBE_H_
20#include <stdio.h>
21
22/*
23** A single VDBE is an opaque structure named "Vdbe".  Only routines
24** in the source file sqliteVdbe.c are allowed to see the insides
25** of this structure.
26*/
27typedef struct Vdbe Vdbe;
28
29/*
30** The names of the following types declared in vdbeInt.h are required
31** for the VdbeOp definition.
32*/
33typedef struct VdbeFunc VdbeFunc;
34typedef struct Mem Mem;
35typedef struct SubProgram SubProgram;
36
37/*
38** A single instruction of the virtual machine has an opcode
39** and as many as three operands.  The instruction is recorded
40** as an instance of the following structure:
41*/
42struct VdbeOp {
43  u8 opcode;          /* What operation to perform */
44  signed char p4type; /* One of the P4_xxx constants for p4 */
45  u8 opflags;         /* Mask of the OPFLG_* flags in opcodes.h */
46  u8 p5;              /* Fifth parameter is an unsigned character */
47  int p1;             /* First operand */
48  int p2;             /* Second parameter (often the jump destination) */
49  int p3;             /* The third parameter */
50  union {             /* fourth parameter */
51    int i;                 /* Integer value if p4type==P4_INT32 */
52    void *p;               /* Generic pointer */
53    char *z;               /* Pointer to data for string (char array) types */
54    i64 *pI64;             /* Used when p4type is P4_INT64 */
55    double *pReal;         /* Used when p4type is P4_REAL */
56    FuncDef *pFunc;        /* Used when p4type is P4_FUNCDEF */
57    VdbeFunc *pVdbeFunc;   /* Used when p4type is P4_VDBEFUNC */
58    CollSeq *pColl;        /* Used when p4type is P4_COLLSEQ */
59    Mem *pMem;             /* Used when p4type is P4_MEM */
60    VTable *pVtab;         /* Used when p4type is P4_VTAB */
61    KeyInfo *pKeyInfo;     /* Used when p4type is P4_KEYINFO */
62    int *ai;               /* Used when p4type is P4_INTARRAY */
63    SubProgram *pProgram;  /* Used when p4type is P4_SUBPROGRAM */
64  } p4;
65#ifdef SQLITE_DEBUG
66  char *zComment;          /* Comment to improve readability */
67#endif
68#ifdef VDBE_PROFILE
69  int cnt;                 /* Number of times this instruction was executed */
70  u64 cycles;              /* Total time spent executing this instruction */
71#endif
72};
73typedef struct VdbeOp VdbeOp;
74
75
76/*
77** A sub-routine used to implement a trigger program.
78*/
79struct SubProgram {
80  VdbeOp *aOp;                  /* Array of opcodes for sub-program */
81  int nOp;                      /* Elements in aOp[] */
82  int nMem;                     /* Number of memory cells required */
83  int nCsr;                     /* Number of cursors required */
84  void *token;                  /* id that may be used to recursive triggers */
85  SubProgram *pNext;            /* Next sub-program already visited */
86};
87
88/*
89** A smaller version of VdbeOp used for the VdbeAddOpList() function because
90** it takes up less space.
91*/
92struct VdbeOpList {
93  u8 opcode;          /* What operation to perform */
94  signed char p1;     /* First operand */
95  signed char p2;     /* Second parameter (often the jump destination) */
96  signed char p3;     /* Third parameter */
97};
98typedef struct VdbeOpList VdbeOpList;
99
100/*
101** Allowed values of VdbeOp.p4type
102*/
103#define P4_NOTUSED    0   /* The P4 parameter is not used */
104#define P4_DYNAMIC  (-1)  /* Pointer to a string obtained from sqliteMalloc() */
105#define P4_STATIC   (-2)  /* Pointer to a static string */
106#define P4_COLLSEQ  (-4)  /* P4 is a pointer to a CollSeq structure */
107#define P4_FUNCDEF  (-5)  /* P4 is a pointer to a FuncDef structure */
108#define P4_KEYINFO  (-6)  /* P4 is a pointer to a KeyInfo structure */
109#define P4_VDBEFUNC (-7)  /* P4 is a pointer to a VdbeFunc structure */
110#define P4_MEM      (-8)  /* P4 is a pointer to a Mem*    structure */
111#define P4_TRANSIENT  0   /* P4 is a pointer to a transient string */
112#define P4_VTAB     (-10) /* P4 is a pointer to an sqlite3_vtab structure */
113#define P4_MPRINTF  (-11) /* P4 is a string obtained from sqlite3_mprintf() */
114#define P4_REAL     (-12) /* P4 is a 64-bit floating point value */
115#define P4_INT64    (-13) /* P4 is a 64-bit signed integer */
116#define P4_INT32    (-14) /* P4 is a 32-bit signed integer */
117#define P4_INTARRAY (-15) /* P4 is a vector of 32-bit integers */
118#define P4_SUBPROGRAM  (-18) /* P4 is a pointer to a SubProgram structure */
119
120/* When adding a P4 argument using P4_KEYINFO, a copy of the KeyInfo structure
121** is made.  That copy is freed when the Vdbe is finalized.  But if the
122** argument is P4_KEYINFO_HANDOFF, the passed in pointer is used.  It still
123** gets freed when the Vdbe is finalized so it still should be obtained
124** from a single sqliteMalloc().  But no copy is made and the calling
125** function should *not* try to free the KeyInfo.
126*/
127#define P4_KEYINFO_HANDOFF (-16)
128#define P4_KEYINFO_STATIC  (-17)
129
130/*
131** The Vdbe.aColName array contains 5n Mem structures, where n is the
132** number of columns of data returned by the statement.
133*/
134#define COLNAME_NAME     0
135#define COLNAME_DECLTYPE 1
136#define COLNAME_DATABASE 2
137#define COLNAME_TABLE    3
138#define COLNAME_COLUMN   4
139#ifdef SQLITE_ENABLE_COLUMN_METADATA
140# define COLNAME_N        5      /* Number of COLNAME_xxx symbols */
141#else
142# ifdef SQLITE_OMIT_DECLTYPE
143#   define COLNAME_N      1      /* Store only the name */
144# else
145#   define COLNAME_N      2      /* Store the name and decltype */
146# endif
147#endif
148
149/*
150** The following macro converts a relative address in the p2 field
151** of a VdbeOp structure into a negative number so that
152** sqlite3VdbeAddOpList() knows that the address is relative.  Calling
153** the macro again restores the address.
154*/
155#define ADDR(X)  (-1-(X))
156
157/*
158** The makefile scans the vdbe.c source file and creates the "opcodes.h"
159** header file that defines a number for each opcode used by the VDBE.
160*/
161#include "opcodes.h"
162
163/*
164** Prototypes for the VDBE interface.  See comments on the implementation
165** for a description of what each of these routines does.
166*/
167Vdbe *sqlite3VdbeCreate(sqlite3*);
168int sqlite3VdbeAddOp0(Vdbe*,int);
169int sqlite3VdbeAddOp1(Vdbe*,int,int);
170int sqlite3VdbeAddOp2(Vdbe*,int,int,int);
171int sqlite3VdbeAddOp3(Vdbe*,int,int,int,int);
172int sqlite3VdbeAddOp4(Vdbe*,int,int,int,int,const char *zP4,int);
173int sqlite3VdbeAddOp4Int(Vdbe*,int,int,int,int,int);
174int sqlite3VdbeAddOpList(Vdbe*, int nOp, VdbeOpList const *aOp);
175void sqlite3VdbeChangeP1(Vdbe*, int addr, int P1);
176void sqlite3VdbeChangeP2(Vdbe*, int addr, int P2);
177void sqlite3VdbeChangeP3(Vdbe*, int addr, int P3);
178void sqlite3VdbeChangeP5(Vdbe*, u8 P5);
179void sqlite3VdbeJumpHere(Vdbe*, int addr);
180void sqlite3VdbeChangeToNoop(Vdbe*, int addr, int N);
181void sqlite3VdbeChangeP4(Vdbe*, int addr, const char *zP4, int N);
182void sqlite3VdbeUsesBtree(Vdbe*, int);
183VdbeOp *sqlite3VdbeGetOp(Vdbe*, int);
184int sqlite3VdbeMakeLabel(Vdbe*);
185void sqlite3VdbeRunOnlyOnce(Vdbe*);
186void sqlite3VdbeDelete(Vdbe*);
187void sqlite3VdbeDeleteObject(sqlite3*,Vdbe*);
188void sqlite3VdbeMakeReady(Vdbe*,int,int,int,int,int,int);
189int sqlite3VdbeFinalize(Vdbe*);
190void sqlite3VdbeResolveLabel(Vdbe*, int);
191int sqlite3VdbeCurrentAddr(Vdbe*);
192#ifdef SQLITE_DEBUG
193  int sqlite3VdbeAssertMayAbort(Vdbe *, int);
194  void sqlite3VdbeTrace(Vdbe*,FILE*);
195#endif
196void sqlite3VdbeResetStepResult(Vdbe*);
197int sqlite3VdbeReset(Vdbe*);
198void sqlite3VdbeSetNumCols(Vdbe*,int);
199int sqlite3VdbeSetColName(Vdbe*, int, int, const char *, void(*)(void*));
200void sqlite3VdbeCountChanges(Vdbe*);
201sqlite3 *sqlite3VdbeDb(Vdbe*);
202void sqlite3VdbeSetSql(Vdbe*, const char *z, int n, int);
203void sqlite3VdbeSwap(Vdbe*,Vdbe*);
204VdbeOp *sqlite3VdbeTakeOpArray(Vdbe*, int*, int*);
205sqlite3_value *sqlite3VdbeGetValue(Vdbe*, int, u8);
206void sqlite3VdbeSetVarmask(Vdbe*, int);
207#ifndef SQLITE_OMIT_TRACE
208  char *sqlite3VdbeExpandSql(Vdbe*, const char*);
209#endif
210
211UnpackedRecord *sqlite3VdbeRecordUnpack(KeyInfo*,int,const void*,char*,int);
212void sqlite3VdbeDeleteUnpackedRecord(UnpackedRecord*);
213int sqlite3VdbeRecordCompare(int,const void*,UnpackedRecord*);
214
215#ifndef SQLITE_OMIT_TRIGGER
216void sqlite3VdbeLinkSubProgram(Vdbe *, SubProgram *);
217#endif
218
219
220#ifndef NDEBUG
221  void sqlite3VdbeComment(Vdbe*, const char*, ...);
222# define VdbeComment(X)  sqlite3VdbeComment X
223  void sqlite3VdbeNoopComment(Vdbe*, const char*, ...);
224# define VdbeNoopComment(X)  sqlite3VdbeNoopComment X
225#else
226# define VdbeComment(X)
227# define VdbeNoopComment(X)
228#endif
229
230#endif
231