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 */ 27 typedef struct Vdbe Vdbe; 28 29 /* 30 ** The names of the following types declared in vdbeInt.h are required 31 ** for the VdbeOp definition. 32 */ 33 typedef struct Mem Mem; 34 typedef struct SubProgram SubProgram; 35 36 /* 37 ** A single instruction of the virtual machine has an opcode 38 ** and as many as three operands. The instruction is recorded 39 ** as an instance of the following structure: 40 */ 41 struct VdbeOp { 42 u8 opcode; /* What operation to perform */ 43 signed char p4type; /* One of the P4_xxx constants for p4 */ 44 u8 opflags; /* Mask of the OPFLG_* flags in opcodes.h */ 45 u8 p5; /* Fifth parameter is an unsigned character */ 46 int p1; /* First operand */ 47 int p2; /* Second parameter (often the jump destination) */ 48 int p3; /* The third parameter */ 49 union { /* fourth parameter */ 50 int i; /* Integer value if p4type==P4_INT32 */ 51 void *p; /* Generic pointer */ 52 char *z; /* Pointer to data for string (char array) types */ 53 i64 *pI64; /* Used when p4type is P4_INT64 */ 54 double *pReal; /* Used when p4type is P4_REAL */ 55 FuncDef *pFunc; /* Used when p4type is P4_FUNCDEF */ 56 CollSeq *pColl; /* Used when p4type is P4_COLLSEQ */ 57 Mem *pMem; /* Used when p4type is P4_MEM */ 58 VTable *pVtab; /* Used when p4type is P4_VTAB */ 59 KeyInfo *pKeyInfo; /* Used when p4type is P4_KEYINFO */ 60 int *ai; /* Used when p4type is P4_INTARRAY */ 61 SubProgram *pProgram; /* Used when p4type is P4_SUBPROGRAM */ 62 int (*xAdvance)(BtCursor *, int *); 63 } p4; 64 #ifdef SQLITE_ENABLE_EXPLAIN_COMMENTS 65 char *zComment; /* Comment to improve readability */ 66 #endif 67 #ifdef VDBE_PROFILE 68 int cnt; /* Number of times this instruction was executed */ 69 u64 cycles; /* Total time spent executing this instruction */ 70 #endif 71 }; 72 typedef struct VdbeOp VdbeOp; 73 74 75 /* 76 ** A sub-routine used to implement a trigger program. 77 */ 78 struct SubProgram { 79 VdbeOp *aOp; /* Array of opcodes for sub-program */ 80 int nOp; /* Elements in aOp[] */ 81 int nMem; /* Number of memory cells required */ 82 int nCsr; /* Number of cursors required */ 83 int nOnce; /* Number of OP_Once instructions */ 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 */ 92 struct 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 }; 98 typedef 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_MEM (-8) /* P4 is a pointer to a Mem* structure */ 110 #define P4_TRANSIENT 0 /* P4 is a pointer to a transient string */ 111 #define P4_VTAB (-10) /* P4 is a pointer to an sqlite3_vtab structure */ 112 #define P4_MPRINTF (-11) /* P4 is a string obtained from sqlite3_mprintf() */ 113 #define P4_REAL (-12) /* P4 is a 64-bit floating point value */ 114 #define P4_INT64 (-13) /* P4 is a 64-bit signed integer */ 115 #define P4_INT32 (-14) /* P4 is a 32-bit signed integer */ 116 #define P4_INTARRAY (-15) /* P4 is a vector of 32-bit integers */ 117 #define P4_SUBPROGRAM (-18) /* P4 is a pointer to a SubProgram structure */ 118 #define P4_ADVANCE (-19) /* P4 is a pointer to BtreeNext() or BtreePrev() */ 119 120 /* Error message codes for OP_Halt */ 121 #define P5_ConstraintNotNull 1 122 #define P5_ConstraintUnique 2 123 #define P5_ConstraintCheck 3 124 #define P5_ConstraintFK 4 125 126 /* 127 ** The Vdbe.aColName array contains 5n Mem structures, where n is the 128 ** number of columns of data returned by the statement. 129 */ 130 #define COLNAME_NAME 0 131 #define COLNAME_DECLTYPE 1 132 #define COLNAME_DATABASE 2 133 #define COLNAME_TABLE 3 134 #define COLNAME_COLUMN 4 135 #ifdef SQLITE_ENABLE_COLUMN_METADATA 136 # define COLNAME_N 5 /* Number of COLNAME_xxx symbols */ 137 #else 138 # ifdef SQLITE_OMIT_DECLTYPE 139 # define COLNAME_N 1 /* Store only the name */ 140 # else 141 # define COLNAME_N 2 /* Store the name and decltype */ 142 # endif 143 #endif 144 145 /* 146 ** The following macro converts a relative address in the p2 field 147 ** of a VdbeOp structure into a negative number so that 148 ** sqlite3VdbeAddOpList() knows that the address is relative. Calling 149 ** the macro again restores the address. 150 */ 151 #define ADDR(X) (-1-(X)) 152 153 /* 154 ** The makefile scans the vdbe.c source file and creates the "opcodes.h" 155 ** header file that defines a number for each opcode used by the VDBE. 156 */ 157 #include "opcodes.h" 158 159 /* 160 ** Prototypes for the VDBE interface. See comments on the implementation 161 ** for a description of what each of these routines does. 162 */ 163 Vdbe *sqlite3VdbeCreate(Parse*); 164 int sqlite3VdbeAddOp0(Vdbe*,int); 165 int sqlite3VdbeAddOp1(Vdbe*,int,int); 166 int sqlite3VdbeAddOp2(Vdbe*,int,int,int); 167 int sqlite3VdbeAddOp3(Vdbe*,int,int,int,int); 168 int sqlite3VdbeAddOp4(Vdbe*,int,int,int,int,const char *zP4,int); 169 int sqlite3VdbeAddOp4Int(Vdbe*,int,int,int,int,int); 170 int sqlite3VdbeAddOpList(Vdbe*, int nOp, VdbeOpList const *aOp); 171 void sqlite3VdbeAddParseSchemaOp(Vdbe*,int,char*); 172 void sqlite3VdbeChangeP1(Vdbe*, u32 addr, int P1); 173 void sqlite3VdbeChangeP2(Vdbe*, u32 addr, int P2); 174 void sqlite3VdbeChangeP3(Vdbe*, u32 addr, int P3); 175 void sqlite3VdbeChangeP5(Vdbe*, u8 P5); 176 void sqlite3VdbeJumpHere(Vdbe*, int addr); 177 void sqlite3VdbeChangeToNoop(Vdbe*, int addr); 178 int sqlite3VdbeDeletePriorOpcode(Vdbe*, u8 op); 179 void sqlite3VdbeChangeP4(Vdbe*, int addr, const char *zP4, int N); 180 void sqlite3VdbeSetP4KeyInfo(Parse*, Index*); 181 void sqlite3VdbeUsesBtree(Vdbe*, int); 182 VdbeOp *sqlite3VdbeGetOp(Vdbe*, int); 183 int sqlite3VdbeMakeLabel(Vdbe*); 184 void sqlite3VdbeRunOnlyOnce(Vdbe*); 185 void sqlite3VdbeDelete(Vdbe*); 186 void sqlite3VdbeClearObject(sqlite3*,Vdbe*); 187 void sqlite3VdbeMakeReady(Vdbe*,Parse*); 188 int sqlite3VdbeFinalize(Vdbe*); 189 void sqlite3VdbeResolveLabel(Vdbe*, int); 190 int sqlite3VdbeCurrentAddr(Vdbe*); 191 #ifdef SQLITE_DEBUG 192 int sqlite3VdbeAssertMayAbort(Vdbe *, int); 193 #endif 194 void sqlite3VdbeResetStepResult(Vdbe*); 195 void sqlite3VdbeRewind(Vdbe*); 196 int sqlite3VdbeReset(Vdbe*); 197 void sqlite3VdbeSetNumCols(Vdbe*,int); 198 int sqlite3VdbeSetColName(Vdbe*, int, int, const char *, void(*)(void*)); 199 void sqlite3VdbeCountChanges(Vdbe*); 200 sqlite3 *sqlite3VdbeDb(Vdbe*); 201 void sqlite3VdbeSetSql(Vdbe*, const char *z, int n, int); 202 void sqlite3VdbeSwap(Vdbe*,Vdbe*); 203 VdbeOp *sqlite3VdbeTakeOpArray(Vdbe*, int*, int*); 204 sqlite3_value *sqlite3VdbeGetBoundValue(Vdbe*, int, u8); 205 void sqlite3VdbeSetVarmask(Vdbe*, int); 206 #ifndef SQLITE_OMIT_TRACE 207 char *sqlite3VdbeExpandSql(Vdbe*, const char*); 208 #endif 209 210 void sqlite3VdbeRecordUnpack(KeyInfo*,int,const void*,UnpackedRecord*); 211 int sqlite3VdbeRecordCompare(int,const void*,UnpackedRecord*); 212 UnpackedRecord *sqlite3VdbeAllocUnpackedRecord(KeyInfo *, char *, int, char **); 213 214 #ifndef SQLITE_OMIT_TRIGGER 215 void sqlite3VdbeLinkSubProgram(Vdbe *, SubProgram *); 216 #endif 217 218 /* Use SQLITE_ENABLE_COMMENTS to enable generation of extra comments on 219 ** each VDBE opcode. 220 ** 221 ** Use the SQLITE_ENABLE_MODULE_COMMENTS macro to see some extra no-op 222 ** comments in VDBE programs that show key decision points in the code 223 ** generator. 224 */ 225 #ifdef SQLITE_ENABLE_EXPLAIN_COMMENTS 226 void sqlite3VdbeComment(Vdbe*, const char*, ...); 227 # define VdbeComment(X) sqlite3VdbeComment X 228 void sqlite3VdbeNoopComment(Vdbe*, const char*, ...); 229 # define VdbeNoopComment(X) sqlite3VdbeNoopComment X 230 # ifdef SQLITE_ENABLE_MODULE_COMMENTS 231 # define VdbeModuleComment(X) sqlite3VdbeNoopComment X 232 # else 233 # define VdbeModuleComment(X) 234 # endif 235 #else 236 # define VdbeComment(X) 237 # define VdbeNoopComment(X) 238 # define VdbeModuleComment(X) 239 #endif 240 241 #endif 242