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 ** $Id: vdbe.h,v 1.130 2008/04/11 14:56:53 drh Exp $ 19 */ 20 #ifndef _SQLITE_VDBE_H_ 21 #define _SQLITE_VDBE_H_ 22 #include <stdio.h> 23 24 /* 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 27 ** of this structure. 28 */ 29 typedef struct Vdbe Vdbe; 30 31 /* 32 ** The names of the following types declared in vdbeInt.h are required 33 ** for the VdbeOp definition. 34 */ 35 typedef struct VdbeFunc VdbeFunc; 36 typedef struct Mem Mem; 37 typedef struct UnpackedRecord UnpackedRecord; 38 39 /* 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: 43 */ 44 struct VdbeOp { 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 } 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 long long cycles; /* Total time spend executing this instruction */ 71 #endif 72 }; 73 typedef struct VdbeOp VdbeOp; 74 75 /* 76 ** A smaller version of VdbeOp used for the VdbeAddOpList() function because 77 ** it takes up less space. 78 */ 79 struct VdbeOpList { 80 u8 opcode; /* What operation to perform */ 81 signed char p1; /* First operand */ 82 signed char p2; /* Second parameter (often the jump destination) */ 83 signed char p3; /* Third parameter */ 84 }; 85 typedef struct VdbeOpList VdbeOpList; 86 87 /* 88 ** Allowed values of VdbeOp.p3type 89 */ 90 #define P4_NOTUSED 0 /* The P4 parameter is not used */ 91 #define P4_DYNAMIC (-1) /* Pointer to a string obtained from sqliteMalloc() */ 92 #define P4_STATIC (-2) /* Pointer to a static string */ 93 #define P4_COLLSEQ (-4) /* P4 is a pointer to a CollSeq structure */ 94 #define P4_FUNCDEF (-5) /* P4 is a pointer to a FuncDef structure */ 95 #define P4_KEYINFO (-6) /* P4 is a pointer to a KeyInfo structure */ 96 #define P4_VDBEFUNC (-7) /* P4 is a pointer to a VdbeFunc structure */ 97 #define P4_MEM (-8) /* P4 is a pointer to a Mem* structure */ 98 #define P4_TRANSIENT (-9) /* P4 is a pointer to a transient string */ 99 #define P4_VTAB (-10) /* P4 is a pointer to an sqlite3_vtab structure */ 100 #define P4_MPRINTF (-11) /* P4 is a string obtained from sqlite3_mprintf() */ 101 #define P4_REAL (-12) /* P4 is a 64-bit floating point value */ 102 #define P4_INT64 (-13) /* P4 is a 64-bit signed integer */ 103 #define P4_INT32 (-14) /* P4 is a 32-bit signed integer */ 104 105 /* When adding a P4 argument using P4_KEYINFO, a copy of the KeyInfo structure 106 ** is made. That copy is freed when the Vdbe is finalized. But if the 107 ** argument is P4_KEYINFO_HANDOFF, the passed in pointer is used. It still 108 ** gets freed when the Vdbe is finalized so it still should be obtained 109 ** from a single sqliteMalloc(). But no copy is made and the calling 110 ** function should *not* try to free the KeyInfo. 111 */ 112 #define P4_KEYINFO_HANDOFF (-9) 113 114 /* 115 ** The Vdbe.aColName array contains 5n Mem structures, where n is the 116 ** number of columns of data returned by the statement. 117 */ 118 #define COLNAME_NAME 0 119 #define COLNAME_DECLTYPE 1 120 #define COLNAME_DATABASE 2 121 #define COLNAME_TABLE 3 122 #define COLNAME_COLUMN 4 123 #ifdef SQLITE_ENABLE_COLUMN_METADATA 124 # define COLNAME_N 5 /* Number of COLNAME_xxx symbols */ 125 #else 126 # ifdef SQLITE_OMIT_DECLTYPE 127 # define COLNAME_N 1 /* Store only the name */ 128 # else 129 # define COLNAME_N 2 /* Store the name and decltype */ 130 # endif 131 #endif 132 133 /* 134 ** The following macro converts a relative address in the p2 field 135 ** of a VdbeOp structure into a negative number so that 136 ** sqlite3VdbeAddOpList() knows that the address is relative. Calling 137 ** the macro again restores the address. 138 */ 139 #define ADDR(X) (-1-(X)) 140 141 /* 142 ** The makefile scans the vdbe.c source file and creates the "opcodes.h" 143 ** header file that defines a number for each opcode used by the VDBE. 144 */ 145 #include "opcodes.h" 146 147 /* 148 ** Prototypes for the VDBE interface. See comments on the implementation 149 ** for a description of what each of these routines does. 150 */ 151 Vdbe *sqlite3VdbeCreate(sqlite3*); 152 int sqlite3VdbeAddOp0(Vdbe*,int); 153 int sqlite3VdbeAddOp1(Vdbe*,int,int); 154 int sqlite3VdbeAddOp2(Vdbe*,int,int,int); 155 int sqlite3VdbeAddOp3(Vdbe*,int,int,int,int); 156 int sqlite3VdbeAddOp4(Vdbe*,int,int,int,int,const char *zP4,int); 157 int sqlite3VdbeAddOpList(Vdbe*, int nOp, VdbeOpList const *aOp); 158 void sqlite3VdbeChangeP1(Vdbe*, int addr, int P1); 159 void sqlite3VdbeChangeP2(Vdbe*, int addr, int P2); 160 void sqlite3VdbeChangeP3(Vdbe*, int addr, int P3); 161 void sqlite3VdbeChangeP5(Vdbe*, u8 P5); 162 void sqlite3VdbeJumpHere(Vdbe*, int addr); 163 void sqlite3VdbeChangeToNoop(Vdbe*, int addr, int N); 164 void sqlite3VdbeChangeP4(Vdbe*, int addr, const char *zP4, int N); 165 void sqlite3VdbeUsesBtree(Vdbe*, int); 166 VdbeOp *sqlite3VdbeGetOp(Vdbe*, int); 167 int sqlite3VdbeMakeLabel(Vdbe*); 168 void sqlite3VdbeDelete(Vdbe*); 169 void sqlite3VdbeMakeReady(Vdbe*,int,int,int,int); 170 int sqlite3VdbeFinalize(Vdbe*); 171 void sqlite3VdbeResolveLabel(Vdbe*, int); 172 int sqlite3VdbeCurrentAddr(Vdbe*); 173 #ifdef SQLITE_DEBUG 174 void sqlite3VdbeTrace(Vdbe*,FILE*); 175 #endif 176 void sqlite3VdbeResetStepResult(Vdbe*); 177 int sqlite3VdbeReset(Vdbe*, int); 178 void sqlite3VdbeSetNumCols(Vdbe*,int); 179 int sqlite3VdbeSetColName(Vdbe*, int, int, const char *, int); 180 void sqlite3VdbeCountChanges(Vdbe*); 181 sqlite3 *sqlite3VdbeDb(Vdbe*); 182 void sqlite3VdbeSetSql(Vdbe*, const char *z, int n); 183 void sqlite3VdbeSwap(Vdbe*,Vdbe*); 184 185 int sqlite3VdbeReleaseMemory(int); 186 UnpackedRecord *sqlite3VdbeRecordUnpack(KeyInfo*,int,const void*,void*,int); 187 void sqlite3VdbeDeleteUnpackedRecord(UnpackedRecord*); 188 int sqlite3VdbeRecordCompare(int,const void*,UnpackedRecord*); 189 190 191 #ifndef NDEBUG 192 void sqlite3VdbeComment(Vdbe*, const char*, ...); 193 # define VdbeComment(X) sqlite3VdbeComment X 194 #else 195 # define VdbeComment(X) 196 #endif 197 198 #endif 199