xref: /sqlite-3.40.0/src/vdbe.h (revision e995d2c2)
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 sqlite3_value 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   u16 p5;             /* Fifth parameter is an unsigned 16-bit integer */
45   int p1;             /* First operand */
46   int p2;             /* Second parameter (often the jump destination) */
47   int p3;             /* The third parameter */
48   union p4union {     /* fourth parameter */
49     int i;                 /* Integer value if p4type==P4_INT32 */
50     void *p;               /* Generic pointer */
51     char *z;               /* Pointer to data for string (char array) types */
52     i64 *pI64;             /* Used when p4type is P4_INT64 */
53     double *pReal;         /* Used when p4type is P4_REAL */
54     FuncDef *pFunc;        /* Used when p4type is P4_FUNCDEF */
55     sqlite3_context *pCtx; /* Used when p4type is P4_FUNCCTX */
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     u32 *ai;               /* Used when p4type is P4_INTARRAY */
61     SubProgram *pProgram;  /* Used when p4type is P4_SUBPROGRAM */
62     Table *pTab;           /* Used when p4type is P4_TABLE */
63 #ifdef SQLITE_ENABLE_CURSOR_HINTS
64     Expr *pExpr;           /* Used when p4type is P4_EXPR */
65 #endif
66   } p4;
67 #ifdef SQLITE_ENABLE_EXPLAIN_COMMENTS
68   char *zComment;          /* Comment to improve readability */
69 #endif
70 #ifdef VDBE_PROFILE
71   u32 cnt;                 /* Number of times this instruction was executed */
72   u64 cycles;              /* Total time spent executing this instruction */
73 #endif
74 #ifdef SQLITE_VDBE_COVERAGE
75   u32 iSrcLine;            /* Source-code line that generated this opcode
76                            ** with flags in the upper 8 bits */
77 #endif
78 };
79 typedef struct VdbeOp VdbeOp;
80 
81 
82 /*
83 ** A sub-routine used to implement a trigger program.
84 */
85 struct SubProgram {
86   VdbeOp *aOp;                  /* Array of opcodes for sub-program */
87   int nOp;                      /* Elements in aOp[] */
88   int nMem;                     /* Number of memory cells required */
89   int nCsr;                     /* Number of cursors required */
90   u8 *aOnce;                    /* Array of OP_Once flags */
91   void *token;                  /* id that may be used to recursive triggers */
92   SubProgram *pNext;            /* Next sub-program already visited */
93 };
94 
95 /*
96 ** A smaller version of VdbeOp used for the VdbeAddOpList() function because
97 ** it takes up less space.
98 */
99 struct VdbeOpList {
100   u8 opcode;          /* What operation to perform */
101   signed char p1;     /* First operand */
102   signed char p2;     /* Second parameter (often the jump destination) */
103   signed char p3;     /* Third parameter */
104 };
105 typedef struct VdbeOpList VdbeOpList;
106 
107 /*
108 ** Allowed values of VdbeOp.p4type
109 */
110 #define P4_NOTUSED      0   /* The P4 parameter is not used */
111 #define P4_TRANSIENT    0   /* P4 is a pointer to a transient string */
112 #define P4_STATIC     (-1)  /* Pointer to a static string */
113 #define P4_COLLSEQ    (-2)  /* P4 is a pointer to a CollSeq structure */
114 #define P4_INT32      (-3)  /* P4 is a 32-bit signed integer */
115 #define P4_SUBPROGRAM (-4)  /* P4 is a pointer to a SubProgram structure */
116 #define P4_TABLE      (-5)  /* P4 is a pointer to a Table structure */
117 /* Above do not own any resources.  Must free those below */
118 #define P4_FREE_IF_LE (-6)
119 #define P4_DYNAMIC    (-6)  /* Pointer to memory from sqliteMalloc() */
120 #define P4_FUNCDEF    (-7)  /* P4 is a pointer to a FuncDef structure */
121 #define P4_KEYINFO    (-8)  /* P4 is a pointer to a KeyInfo structure */
122 #define P4_EXPR       (-9) /* P4 is a pointer to an Expr tree */
123 #define P4_MEM        (-10) /* P4 is a pointer to a Mem*    structure */
124 #define P4_VTAB       (-11) /* P4 is a pointer to an sqlite3_vtab structure */
125 #define P4_REAL       (-12) /* P4 is a 64-bit floating point value */
126 #define P4_INT64      (-13) /* P4 is a 64-bit signed integer */
127 #define P4_INTARRAY   (-14) /* P4 is a vector of 32-bit integers */
128 #define P4_FUNCCTX    (-15) /* P4 is a pointer to an sqlite3_context object */
129 
130 /* Error message codes for OP_Halt */
131 #define P5_ConstraintNotNull 1
132 #define P5_ConstraintUnique  2
133 #define P5_ConstraintCheck   3
134 #define P5_ConstraintFK      4
135 
136 /*
137 ** The Vdbe.aColName array contains 5n Mem structures, where n is the
138 ** number of columns of data returned by the statement.
139 */
140 #define COLNAME_NAME     0
141 #define COLNAME_DECLTYPE 1
142 #define COLNAME_DATABASE 2
143 #define COLNAME_TABLE    3
144 #define COLNAME_COLUMN   4
145 #ifdef SQLITE_ENABLE_COLUMN_METADATA
146 # define COLNAME_N        5      /* Number of COLNAME_xxx symbols */
147 #else
148 # ifdef SQLITE_OMIT_DECLTYPE
149 #   define COLNAME_N      1      /* Store only the name */
150 # else
151 #   define COLNAME_N      2      /* Store the name and decltype */
152 # endif
153 #endif
154 
155 /*
156 ** The following macro converts a label returned by sqlite3VdbeMakeLabel()
157 ** into an index into the Parse.aLabel[] array that contains the resolved
158 ** address of that label.
159 */
160 #define ADDR(X)  (~(X))
161 
162 /*
163 ** The makefile scans the vdbe.c source file and creates the "opcodes.h"
164 ** header file that defines a number for each opcode used by the VDBE.
165 */
166 #include "opcodes.h"
167 
168 /*
169 ** Additional non-public SQLITE_PREPARE_* flags
170 */
171 #define SQLITE_PREPARE_SAVESQL  0x80  /* Preserve SQL text */
172 #define SQLITE_PREPARE_MASK     0x0f  /* Mask of public flags */
173 
174 /*
175 ** Prototypes for the VDBE interface.  See comments on the implementation
176 ** for a description of what each of these routines does.
177 */
178 Vdbe *sqlite3VdbeCreate(Parse*);
179 Parse *sqlite3VdbeParser(Vdbe*);
180 int sqlite3VdbeAddOp0(Vdbe*,int);
181 int sqlite3VdbeAddOp1(Vdbe*,int,int);
182 int sqlite3VdbeAddOp2(Vdbe*,int,int,int);
183 int sqlite3VdbeGoto(Vdbe*,int);
184 int sqlite3VdbeLoadString(Vdbe*,int,const char*);
185 void sqlite3VdbeMultiLoad(Vdbe*,int,const char*,...);
186 int sqlite3VdbeAddOp3(Vdbe*,int,int,int,int);
187 int sqlite3VdbeAddOp4(Vdbe*,int,int,int,int,const char *zP4,int);
188 int sqlite3VdbeAddOp4Dup8(Vdbe*,int,int,int,int,const u8*,int);
189 int sqlite3VdbeAddOp4Int(Vdbe*,int,int,int,int,int);
190 int sqlite3VdbeAddFunctionCall(Parse*,int,int,int,int,const FuncDef*,int);
191 void sqlite3VdbeEndCoroutine(Vdbe*,int);
192 #if defined(SQLITE_DEBUG) && !defined(SQLITE_TEST_REALLOC_STRESS)
193   void sqlite3VdbeVerifyNoMallocRequired(Vdbe *p, int N);
194   void sqlite3VdbeVerifyNoResultRow(Vdbe *p);
195 #else
196 # define sqlite3VdbeVerifyNoMallocRequired(A,B)
197 # define sqlite3VdbeVerifyNoResultRow(A)
198 #endif
199 #if defined(SQLITE_DEBUG)
200   void sqlite3VdbeVerifyAbortable(Vdbe *p, int);
201   void sqlite3VdbeNoJumpsOutsideSubrtn(Vdbe*,int,int,int);
202 #else
203 # define sqlite3VdbeVerifyAbortable(A,B)
204 # define sqlite3VdbeNoJumpsOutsideSubrtn(A,B,C,D)
205 #endif
206 VdbeOp *sqlite3VdbeAddOpList(Vdbe*, int nOp, VdbeOpList const *aOp,int iLineno);
207 #ifndef SQLITE_OMIT_EXPLAIN
208   void sqlite3VdbeExplain(Parse*,u8,const char*,...);
209   void sqlite3VdbeExplainPop(Parse*);
210   int sqlite3VdbeExplainParent(Parse*);
211 # define ExplainQueryPlan(P)        sqlite3VdbeExplain P
212 # define ExplainQueryPlanPop(P)     sqlite3VdbeExplainPop(P)
213 # define ExplainQueryPlanParent(P)  sqlite3VdbeExplainParent(P)
214 #else
215 # define ExplainQueryPlan(P)
216 # define ExplainQueryPlanPop(P)
217 # define ExplainQueryPlanParent(P) 0
218 # define sqlite3ExplainBreakpoint(A,B) /*no-op*/
219 #endif
220 #if defined(SQLITE_DEBUG) && !defined(SQLITE_OMIT_EXPLAIN)
221   void sqlite3ExplainBreakpoint(const char*,const char*);
222 #else
223 # define sqlite3ExplainBreakpoint(A,B) /*no-op*/
224 #endif
225 void sqlite3VdbeAddParseSchemaOp(Vdbe*, int, char*, u16);
226 void sqlite3VdbeChangeOpcode(Vdbe*, int addr, u8);
227 void sqlite3VdbeChangeP1(Vdbe*, int addr, int P1);
228 void sqlite3VdbeChangeP2(Vdbe*, int addr, int P2);
229 void sqlite3VdbeChangeP3(Vdbe*, int addr, int P3);
230 void sqlite3VdbeChangeP5(Vdbe*, u16 P5);
231 void sqlite3VdbeTypeofColumn(Vdbe*, int);
232 void sqlite3VdbeJumpHere(Vdbe*, int addr);
233 void sqlite3VdbeJumpHereOrPopInst(Vdbe*, int addr);
234 int sqlite3VdbeChangeToNoop(Vdbe*, int addr);
235 int sqlite3VdbeDeletePriorOpcode(Vdbe*, u8 op);
236 #ifdef SQLITE_DEBUG
237   void sqlite3VdbeReleaseRegisters(Parse*,int addr, int n, u32 mask, int);
238 #else
239 # define sqlite3VdbeReleaseRegisters(P,A,N,M,F)
240 #endif
241 void sqlite3VdbeChangeP4(Vdbe*, int addr, const char *zP4, int N);
242 void sqlite3VdbeAppendP4(Vdbe*, void *pP4, int p4type);
243 void sqlite3VdbeSetP4KeyInfo(Parse*, Index*);
244 void sqlite3VdbeUsesBtree(Vdbe*, int);
245 VdbeOp *sqlite3VdbeGetOp(Vdbe*, int);
246 VdbeOp *sqlite3VdbeGetLastOp(Vdbe*);
247 int sqlite3VdbeMakeLabel(Parse*);
248 void sqlite3VdbeRunOnlyOnce(Vdbe*);
249 void sqlite3VdbeReusable(Vdbe*);
250 void sqlite3VdbeDelete(Vdbe*);
251 void sqlite3VdbeMakeReady(Vdbe*,Parse*);
252 int sqlite3VdbeFinalize(Vdbe*);
253 void sqlite3VdbeResolveLabel(Vdbe*, int);
254 int sqlite3VdbeCurrentAddr(Vdbe*);
255 #ifdef SQLITE_DEBUG
256   int sqlite3VdbeAssertMayAbort(Vdbe *, int);
257 #endif
258 void sqlite3VdbeResetStepResult(Vdbe*);
259 void sqlite3VdbeRewind(Vdbe*);
260 int sqlite3VdbeReset(Vdbe*);
261 void sqlite3VdbeSetNumCols(Vdbe*,int);
262 int sqlite3VdbeSetColName(Vdbe*, int, int, const char *, void(*)(void*));
263 void sqlite3VdbeCountChanges(Vdbe*);
264 sqlite3 *sqlite3VdbeDb(Vdbe*);
265 u8 sqlite3VdbePrepareFlags(Vdbe*);
266 void sqlite3VdbeSetSql(Vdbe*, const char *z, int n, u8);
267 #ifdef SQLITE_ENABLE_NORMALIZE
268 void sqlite3VdbeAddDblquoteStr(sqlite3*,Vdbe*,const char*);
269 int sqlite3VdbeUsesDoubleQuotedString(Vdbe*,const char*);
270 #endif
271 void sqlite3VdbeSwap(Vdbe*,Vdbe*);
272 VdbeOp *sqlite3VdbeTakeOpArray(Vdbe*, int*, int*);
273 sqlite3_value *sqlite3VdbeGetBoundValue(Vdbe*, int, u8);
274 void sqlite3VdbeSetVarmask(Vdbe*, int);
275 #ifndef SQLITE_OMIT_TRACE
276   char *sqlite3VdbeExpandSql(Vdbe*, const char*);
277 #endif
278 int sqlite3MemCompare(const Mem*, const Mem*, const CollSeq*);
279 int sqlite3BlobCompare(const Mem*, const Mem*);
280 
281 void sqlite3VdbeRecordUnpack(KeyInfo*,int,const void*,UnpackedRecord*);
282 int sqlite3VdbeRecordCompare(int,const void*,UnpackedRecord*);
283 int sqlite3VdbeRecordCompareWithSkip(int, const void *, UnpackedRecord *, int);
284 UnpackedRecord *sqlite3VdbeAllocUnpackedRecord(KeyInfo*);
285 
286 typedef int (*RecordCompare)(int,const void*,UnpackedRecord*);
287 RecordCompare sqlite3VdbeFindCompare(UnpackedRecord*);
288 
289 void sqlite3VdbeLinkSubProgram(Vdbe *, SubProgram *);
290 int sqlite3VdbeHasSubProgram(Vdbe*);
291 
292 int sqlite3NotPureFunc(sqlite3_context*);
293 #ifdef SQLITE_ENABLE_BYTECODE_VTAB
294 int sqlite3VdbeBytecodeVtabInit(sqlite3*);
295 #endif
296 
297 /* Use SQLITE_ENABLE_COMMENTS to enable generation of extra comments on
298 ** each VDBE opcode.
299 **
300 ** Use the SQLITE_ENABLE_MODULE_COMMENTS macro to see some extra no-op
301 ** comments in VDBE programs that show key decision points in the code
302 ** generator.
303 */
304 #ifdef SQLITE_ENABLE_EXPLAIN_COMMENTS
305   void sqlite3VdbeComment(Vdbe*, const char*, ...);
306 # define VdbeComment(X)  sqlite3VdbeComment X
307   void sqlite3VdbeNoopComment(Vdbe*, const char*, ...);
308 # define VdbeNoopComment(X)  sqlite3VdbeNoopComment X
309 # ifdef SQLITE_ENABLE_MODULE_COMMENTS
310 #   define VdbeModuleComment(X)  sqlite3VdbeNoopComment X
311 # else
312 #   define VdbeModuleComment(X)
313 # endif
314 #else
315 # define VdbeComment(X)
316 # define VdbeNoopComment(X)
317 # define VdbeModuleComment(X)
318 #endif
319 
320 /*
321 ** The VdbeCoverage macros are used to set a coverage testing point
322 ** for VDBE branch instructions.  The coverage testing points are line
323 ** numbers in the sqlite3.c source file.  VDBE branch coverage testing
324 ** only works with an amalagmation build.  That's ok since a VDBE branch
325 ** coverage build designed for testing the test suite only.  No application
326 ** should ever ship with VDBE branch coverage measuring turned on.
327 **
328 **    VdbeCoverage(v)                  // Mark the previously coded instruction
329 **                                     // as a branch
330 **
331 **    VdbeCoverageIf(v, conditional)   // Mark previous if conditional true
332 **
333 **    VdbeCoverageAlwaysTaken(v)       // Previous branch is always taken
334 **
335 **    VdbeCoverageNeverTaken(v)        // Previous branch is never taken
336 **
337 **    VdbeCoverageNeverNull(v)         // Previous three-way branch is only
338 **                                     // taken on the first two ways.  The
339 **                                     // NULL option is not possible
340 **
341 **    VdbeCoverageEqNe(v)              // Previous OP_Jump is only interested
342 **                                     // in distingishing equal and not-equal.
343 **
344 ** Every VDBE branch operation must be tagged with one of the macros above.
345 ** If not, then when "make test" is run with -DSQLITE_VDBE_COVERAGE and
346 ** -DSQLITE_DEBUG then an ALWAYS() will fail in the vdbeTakeBranch()
347 ** routine in vdbe.c, alerting the developer to the missed tag.
348 **
349 ** During testing, the test application will invoke
350 ** sqlite3_test_control(SQLITE_TESTCTRL_VDBE_COVERAGE,...) to set a callback
351 ** routine that is invoked as each bytecode branch is taken.  The callback
352 ** contains the sqlite3.c source line number ov the VdbeCoverage macro and
353 ** flags to indicate whether or not the branch was taken.  The test application
354 ** is responsible for keeping track of this and reporting byte-code branches
355 ** that are never taken.
356 **
357 ** See the VdbeBranchTaken() macro and vdbeTakeBranch() function in the
358 ** vdbe.c source file for additional information.
359 */
360 #ifdef SQLITE_VDBE_COVERAGE
361   void sqlite3VdbeSetLineNumber(Vdbe*,int);
362 # define VdbeCoverage(v) sqlite3VdbeSetLineNumber(v,__LINE__)
363 # define VdbeCoverageIf(v,x) if(x)sqlite3VdbeSetLineNumber(v,__LINE__)
364 # define VdbeCoverageAlwaysTaken(v) \
365          sqlite3VdbeSetLineNumber(v,__LINE__|0x5000000);
366 # define VdbeCoverageNeverTaken(v) \
367          sqlite3VdbeSetLineNumber(v,__LINE__|0x6000000);
368 # define VdbeCoverageNeverNull(v) \
369          sqlite3VdbeSetLineNumber(v,__LINE__|0x4000000);
370 # define VdbeCoverageNeverNullIf(v,x) \
371          if(x)sqlite3VdbeSetLineNumber(v,__LINE__|0x4000000);
372 # define VdbeCoverageEqNe(v) \
373          sqlite3VdbeSetLineNumber(v,__LINE__|0x8000000);
374 # define VDBE_OFFSET_LINENO(x) (__LINE__+x)
375 #else
376 # define VdbeCoverage(v)
377 # define VdbeCoverageIf(v,x)
378 # define VdbeCoverageAlwaysTaken(v)
379 # define VdbeCoverageNeverTaken(v)
380 # define VdbeCoverageNeverNull(v)
381 # define VdbeCoverageNeverNullIf(v,x)
382 # define VdbeCoverageEqNe(v)
383 # define VDBE_OFFSET_LINENO(x) 0
384 #endif
385 
386 #ifdef SQLITE_ENABLE_STMT_SCANSTATUS
387 void sqlite3VdbeScanStatus(Vdbe*, int, int, int, LogEst, const char*);
388 #else
389 # define sqlite3VdbeScanStatus(a,b,c,d,e)
390 #endif
391 
392 #if defined(SQLITE_DEBUG) || defined(VDBE_PROFILE)
393 void sqlite3VdbePrintOp(FILE*, int, VdbeOp*);
394 #endif
395 
396 #endif /* SQLITE_VDBE_H */
397