src/vdbeInt.h

   1 /*
   2 ** 2003 September 6
   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 ** This is the header file for information that is private to the
  13 ** VDBE.  This information used to all be at the top of the single
  14 ** source code file "vdbe.c".  When that file became too big (over
  15 ** 6000 lines long) it was split up into several smaller files and
  16 ** this header information was factored out.
  17 */
  18 #ifndef _VDBEINT_H_
  19 #define _VDBEINT_H_
  20
  21 /*
  22 ** The maximum number of times that a statement will try to reparse
  23 ** itself before giving up and returning SQLITE_SCHEMA.
  24 */
  25 #ifndef SQLITE_MAX_SCHEMA_RETRY
  26 # define SQLITE_MAX_SCHEMA_RETRY 50
  27 #endif
  28
  29 /*
  30 ** SQL is translated into a sequence of instructions to be
  31 ** executed by a virtual machine.  Each instruction is an instance
  32 ** of the following structure.
  33 */
  34 typedef struct VdbeOp Op;
  35
  36 /*
  37 ** Boolean values
  38 */
  39 typedef unsigned char Bool;
  40
  41 /* Opaque type used by code in vdbesort.c */
  42 typedef struct VdbeSorter VdbeSorter;
  43
  44 /* Opaque type used by the explainer */
  45 typedef struct Explain Explain;
  46
  47 /*
  48 ** A cursor is a pointer into a single BTree within a database file.
  49 ** The cursor can seek to a BTree entry with a particular key, or
  50 ** loop over all entries of the Btree.  You can also insert new BTree
  51 ** entries or retrieve the key or data from the entry that the cursor
  52 ** is currently pointing to.
  53 **
  54 ** Every cursor that the virtual machine has open is represented by an
  55 ** instance of the following structure.
  56 */
  57 struct VdbeCursor {
  58   BtCursor *pCursor;    /* The cursor structure of the backend */
  59   Btree *pBt;           /* Separate file holding temporary table */
  60   KeyInfo *pKeyInfo;    /* Info about index keys needed by index cursors */
  61   int iDb;              /* Index of cursor database in db->aDb[] (or -1) */
  62   int pseudoTableReg;   /* Register holding pseudotable content. */
  63   int nField;           /* Number of fields in the header */
  64   Bool zeroed;          /* True if zeroed out and ready for reuse */
  65   Bool rowidIsValid;    /* True if lastRowid is valid */
  66   Bool atFirst;         /* True if pointing to first entry */
  67   Bool useRandomRowid;  /* Generate new record numbers semi-randomly */
  68   Bool nullRow;         /* True if pointing to a row with no data */
  69   Bool deferredMoveto;  /* A call to sqlite3BtreeMoveto() is needed */
  70   Bool isTable;         /* True if a table requiring integer keys */
  71   Bool isIndex;         /* True if an index containing keys only - no data */
  72   Bool isOrdered;       /* True if the underlying table is BTREE_UNORDERED */
  73   Bool isSorter;        /* True if a new-style sorter */
  74   Bool multiPseudo;     /* Multi-register pseudo-cursor */
  75   sqlite3_vtab_cursor *pVtabCursor;  /* The cursor for a virtual table */
  76   const sqlite3_module *pModule;     /* Module for cursor pVtabCursor */
  77   i64 seqCount;         /* Sequence counter */
  78   i64 movetoTarget;     /* Argument to the deferred sqlite3BtreeMoveto() */
  79   i64 lastRowid;        /* Last rowid from a Next or NextIdx operation */
  80   VdbeSorter *pSorter;  /* Sorter object for OP_SorterOpen cursors */
  81
  82   /* Result of last sqlite3BtreeMoveto() done by an OP_NotExists or
  83   ** OP_IsUnique opcode on this cursor. */
  84   int seekResult;
  85
  86   /* Cached information about the header for the data record that the
  87   ** cursor is currently pointing to.  Only valid if cacheStatus matches
  88   ** Vdbe.cacheCtr.  Vdbe.cacheCtr will never take on the value of
  89   ** CACHE_STALE and so setting cacheStatus=CACHE_STALE guarantees that
  90   ** the cache is out of date.
  91   **
  92   ** aRow might point to (ephemeral) data for the current row, or it might
  93   ** be NULL.
  94   */
  95   u32 cacheStatus;      /* Cache is valid if this matches Vdbe.cacheCtr */
  96   int payloadSize;      /* Total number of bytes in the record */
  97   u32 *aType;           /* Type values for all entries in the record */
  98   u32 *aOffset;         /* Cached offsets to the start of each columns data */
  99   u8 *aRow;             /* Data for the current row, if all on one page */
 100 };
 101 typedef struct VdbeCursor VdbeCursor;
 102
 103 /*
 104 ** When a sub-program is executed (OP_Program), a structure of this type
 105 ** is allocated to store the current value of the program counter, as
 106 ** well as the current memory cell array and various other frame specific
 107 ** values stored in the Vdbe struct. When the sub-program is finished,
 108 ** these values are copied back to the Vdbe from the VdbeFrame structure,
 109 ** restoring the state of the VM to as it was before the sub-program
 110 ** began executing.
 111 **
 112 ** The memory for a VdbeFrame object is allocated and managed by a memory
 113 ** cell in the parent (calling) frame. When the memory cell is deleted or
 114 ** overwritten, the VdbeFrame object is not freed immediately. Instead, it
 115 ** is linked into the Vdbe.pDelFrame list. The contents of the Vdbe.pDelFrame
 116 ** list is deleted when the VM is reset in VdbeHalt(). The reason for doing
 117 ** this instead of deleting the VdbeFrame immediately is to avoid recursive
 118 ** calls to sqlite3VdbeMemRelease() when the memory cells belonging to the
 119 ** child frame are released.
 120 **
 121 ** The currently executing frame is stored in Vdbe.pFrame. Vdbe.pFrame is
 122 ** set to NULL if the currently executing frame is the main program.
 123 */
 124 typedef struct VdbeFrame VdbeFrame;
 125 struct VdbeFrame {
 126   Vdbe *v;                /* VM this frame belongs to */
 127   VdbeFrame *pParent;     /* Parent of this frame, or NULL if parent is main */
 128   Op *aOp;                /* Program instructions for parent frame */
 129   Mem *aMem;              /* Array of memory cells for parent frame */
 130   u8 *aOnceFlag;          /* Array of OP_Once flags for parent frame */
 131   VdbeCursor **apCsr;     /* Array of Vdbe cursors for parent frame */
 132   void *token;            /* Copy of SubProgram.token */
 133   i64 lastRowid;          /* Last insert rowid (sqlite3.lastRowid) */
 134   int nCursor;            /* Number of entries in apCsr */
 135   int pc;                 /* Program Counter in parent (calling) frame */
 136   int nOp;                /* Size of aOp array */
 137   int nMem;               /* Number of entries in aMem */
 138   int nOnceFlag;          /* Number of entries in aOnceFlag */
 139   int nChildMem;          /* Number of memory cells for child frame */
 140   int nChildCsr;          /* Number of cursors for child frame */
 141   int nChange;            /* Statement changes (Vdbe.nChanges)     */
 142 };
 143
 144 #define VdbeFrameMem(p) ((Mem *)&((u8 *)p)[ROUND8(sizeof(VdbeFrame))])
 145
 146 /*
 147 ** A value for VdbeCursor.cacheValid that means the cache is always invalid.
 148 */
 149 #define CACHE_STALE 0
 150
 151 /*
 152 ** Internally, the vdbe manipulates nearly all SQL values as Mem
 153 ** structures. Each Mem struct may cache multiple representations (string,
 154 ** integer etc.) of the same value.
 155 */
 156 struct Mem {
 157   sqlite3 *db;        /* The associated database connection */
 158   char *z;            /* String or BLOB value */
 159   double r;           /* Real value */
 160   union {
 161     i64 i;              /* Integer value used when MEM_Int is set in flags */
 162     int nZero;          /* Used when bit MEM_Zero is set in flags */
 163     FuncDef *pDef;      /* Used only when flags==MEM_Agg */
 164     RowSet *pRowSet;    /* Used only when flags==MEM_RowSet */
 165     VdbeFrame *pFrame;  /* Used when flags==MEM_Frame */
 166   } u;
 167   int n;              /* Number of characters in string value, excluding '\0' */
 168   u16 flags;          /* Some combination of MEM_Null, MEM_Str, MEM_Dyn, etc. */
 169   u8  type;           /* One of SQLITE_NULL, SQLITE_TEXT, SQLITE_INTEGER, etc */
 170   u8  enc;            /* SQLITE_UTF8, SQLITE_UTF16BE, SQLITE_UTF16LE */
 171 #ifdef SQLITE_DEBUG
 172   Mem *pScopyFrom;    /* This Mem is a shallow copy of pScopyFrom */
 173   void *pFiller;      /* So that sizeof(Mem) is a multiple of 8 */
 174 #endif
 175   void (*xDel)(void *);  /* If not null, call this function to delete Mem.z */
 176   char *zMalloc;      /* Dynamic buffer allocated by sqlite3_malloc() */
 177 };
 178
 179 /* One or more of the following flags are set to indicate the validOK
 180 ** representations of the value stored in the Mem struct.
 181 **
 182 ** If the MEM_Null flag is set, then the value is an SQL NULL value.
 183 ** No other flags may be set in this case.
 184 **
 185 ** If the MEM_Str flag is set then Mem.z points at a string representation.
 186 ** Usually this is encoded in the same unicode encoding as the main
 187 ** database (see below for exceptions). If the MEM_Term flag is also
 188 ** set, then the string is nul terminated. The MEM_Int and MEM_Real
 189 ** flags may coexist with the MEM_Str flag.
 190 */
 191 #define MEM_Null      0x0001   /* Value is NULL */
 192 #define MEM_Str       0x0002   /* Value is a string */
 193 #define MEM_Int       0x0004   /* Value is an integer */
 194 #define MEM_Real      0x0008   /* Value is a real number */
 195 #define MEM_Blob      0x0010   /* Value is a BLOB */
 196 #define MEM_RowSet    0x0020   /* Value is a RowSet object */
 197 #define MEM_Frame     0x0040   /* Value is a VdbeFrame object */
 198 #define MEM_Invalid   0x0080   /* Value is undefined */
 199 #define MEM_Cleared   0x0100   /* NULL set by OP_Null, not from data */
 200 #define MEM_TypeMask  0x01ff   /* Mask of type bits */
 201
 202
 203 /* Whenever Mem contains a valid string or blob representation, one of
 204 ** the following flags must be set to determine the memory management
 205 ** policy for Mem.z.  The MEM_Term flag tells us whether or not the
 206 ** string is \000 or \u0000 terminated
 207 */
 208 #define MEM_Term      0x0200   /* String rep is nul terminated */
 209 #define MEM_Dyn       0x0400   /* Need to call sqliteFree() on Mem.z */
 210 #define MEM_Static    0x0800   /* Mem.z points to a static string */
 211 #define MEM_Ephem     0x1000   /* Mem.z points to an ephemeral string */
 212 #define MEM_Agg       0x2000   /* Mem.z points to an agg function context */
 213 #define MEM_Zero      0x4000   /* Mem.i contains count of 0s appended to blob */
 214 #ifdef SQLITE_OMIT_INCRBLOB
 215   #undef MEM_Zero
 216   #define MEM_Zero 0x0000
 217 #endif
 218
 219 /*
 220 ** Clear any existing type flags from a Mem and replace them with f
 221 */
 222 #define MemSetTypeFlag(p, f) \
 223    ((p)->flags = ((p)->flags&~(MEM_TypeMask|MEM_Zero))|f)
 224
 225 /*
 226 ** Return true if a memory cell is not marked as invalid.  This macro
 227 ** is for use inside assert() statements only.
 228 */
 229 #ifdef SQLITE_DEBUG
 230 #define memIsValid(M)  ((M)->flags & MEM_Invalid)==0
 231 #endif
 232
 233
 234 /* A VdbeFunc is just a FuncDef (defined in sqliteInt.h) that contains
 235 ** additional information about auxiliary information bound to arguments
 236 ** of the function.  This is used to implement the sqlite3_get_auxdata()
 237 ** and sqlite3_set_auxdata() APIs.  The "auxdata" is some auxiliary data
 238 ** that can be associated with a constant argument to a function.  This
 239 ** allows functions such as "regexp" to compile their constant regular
 240 ** expression argument once and reused the compiled code for multiple
 241 ** invocations.
 242 */
 243 struct VdbeFunc {
 244   FuncDef *pFunc;               /* The definition of the function */
 245   int nAux;                     /* Number of entries allocated for apAux[] */
 246   struct AuxData {
 247     void *pAux;                   /* Aux data for the i-th argument */
 248     void (*xDelete)(void *);      /* Destructor for the aux data */
 249   } apAux[1];                   /* One slot for each function argument */
 250 };
 251
 252 /*
 253 ** The "context" argument for a installable function.  A pointer to an
 254 ** instance of this structure is the first argument to the routines used
 255 ** implement the SQL functions.
 256 **
 257 ** There is a typedef for this structure in sqlite.h.  So all routines,
 258 ** even the public interface to SQLite, can use a pointer to this structure.
 259 ** But this file is the only place where the internal details of this
 260 ** structure are known.
 261 **
 262 ** This structure is defined inside of vdbeInt.h because it uses substructures
 263 ** (Mem) which are only defined there.
 264 */
 265 struct sqlite3_context {
 266   FuncDef *pFunc;       /* Pointer to function information.  MUST BE FIRST */
 267   VdbeFunc *pVdbeFunc;  /* Auxilary data, if created. */
 268   Mem s;                /* The return value is stored here */
 269   Mem *pMem;            /* Memory cell used to store aggregate context */
 270   CollSeq *pColl;       /* Collating sequence */
 271   int isError;          /* Error code returned by the function. */
 272   int skipFlag;         /* Skip skip accumulator loading if true */
 273 };
 274
 275 /*
 276 ** An Explain object accumulates indented output which is helpful
 277 ** in describing recursive data structures.
 278 */
 279 struct Explain {
 280   Vdbe *pVdbe;       /* Attach the explanation to this Vdbe */
 281   StrAccum str;      /* The string being accumulated */
 282   int nIndent;       /* Number of elements in aIndent */
 283   u16 aIndent[100];  /* Levels of indentation */
 284   char zBase[100];   /* Initial space */
 285 };
 286
 287 /* A bitfield type for use inside of structures.  Always follow with :N where
 288 ** N is the number of bits.
 289 */
 290 typedef unsigned bft;  /* Bit Field Type */
 291
 292 /*
 293 ** An instance of the virtual machine.  This structure contains the complete
 294 ** state of the virtual machine.
 295 **
 296 ** The "sqlite3_stmt" structure pointer that is returned by sqlite3_prepare()
 297 ** is really a pointer to an instance of this structure.
 298 **
 299 ** The Vdbe.inVtabMethod variable is set to non-zero for the duration of
 300 ** any virtual table method invocations made by the vdbe program. It is
 301 ** set to 2 for xDestroy method calls and 1 for all other methods. This
 302 ** variable is used for two purposes: to allow xDestroy methods to execute
 303 ** "DROP TABLE" statements and to prevent some nasty side effects of
 304 ** malloc failure when SQLite is invoked recursively by a virtual table
 305 ** method function.
 306 */
 307 struct Vdbe {
 308   sqlite3 *db;            /* The database connection that owns this statement */
 309   Op *aOp;                /* Space to hold the virtual machine's program */
 310   Mem *aMem;              /* The memory locations */
 311   Mem **apArg;            /* Arguments to currently executing user function */
 312   Mem *aColName;          /* Column names to return */
 313   Mem *pResultSet;        /* Pointer to an array of results */
 314   int nMem;               /* Number of memory locations currently allocated */
 315   int nOp;                /* Number of instructions in the program */
 316   int nOpAlloc;           /* Number of slots allocated for aOp[] */
 317   int nLabel;             /* Number of labels used */
 318   int *aLabel;            /* Space to hold the labels */
 319   u16 nResColumn;         /* Number of columns in one row of the result set */
 320   int nCursor;            /* Number of slots in apCsr[] */
 321   u32 magic;              /* Magic number for sanity checking */
 322   char *zErrMsg;          /* Error message written here */
 323   Vdbe *pPrev,*pNext;     /* Linked list of VDBEs with the same Vdbe.db */
 324   VdbeCursor **apCsr;     /* One element of this array for each open cursor */
 325   Mem *aVar;              /* Values for the OP_Variable opcode. */
 326   char **azVar;           /* Name of variables */
 327   ynVar nVar;             /* Number of entries in aVar[] */
 328   ynVar nzVar;            /* Number of entries in azVar[] */
 329   u32 cacheCtr;           /* VdbeCursor row cache generation counter */
 330   int pc;                 /* The program counter */
 331   int rc;                 /* Value to return */
 332   u8 errorAction;         /* Recovery action to do in case of an error */
 333   u8 minWriteFileFormat;  /* Minimum file format for writable database files */
 334   bft explain:2;          /* True if EXPLAIN present on SQL command */
 335   bft inVtabMethod:2;     /* See comments above */
 336   bft changeCntOn:1;      /* True to update the change-counter */
 337   bft expired:1;          /* True if the VM needs to be recompiled */
 338   bft runOnlyOnce:1;      /* Automatically expire on reset */
 339   bft usesStmtJournal:1;  /* True if uses a statement journal */
 340   bft readOnly:1;         /* True for read-only statements */
 341   bft isPrepareV2:1;      /* True if prepared with prepare_v2() */
 342   bft doingRerun:1;       /* True if rerunning after an auto-reprepare */
 343   int nChange;            /* Number of db changes made since last reset */
 344   yDbMask btreeMask;      /* Bitmask of db->aDb[] entries referenced */
 345   yDbMask lockMask;       /* Subset of btreeMask that requires a lock */
 346   int iStatement;         /* Statement number (or 0 if has not opened stmt) */
 347   int aCounter[3];        /* Counters used by sqlite3_stmt_status() */
 348 #ifndef SQLITE_OMIT_TRACE
 349   i64 startTime;          /* Time when query started - used for profiling */
 350 #endif
 351   i64 nFkConstraint;      /* Number of imm. FK constraints this VM */
 352   i64 nStmtDefCons;       /* Number of def. constraints when stmt started */
 353   char *zSql;             /* Text of the SQL statement that generated this */
 354   void *pFree;            /* Free this when deleting the vdbe */
 355 #ifdef SQLITE_DEBUG
 356   FILE *trace;            /* Write an execution trace here, if not NULL */
 357 #endif
 358 #ifdef SQLITE_ENABLE_TREE_EXPLAIN
 359   Explain *pExplain;      /* The explainer */
 360   char *zExplain;         /* Explanation of data structures */
 361 #endif
 362   VdbeFrame *pFrame;      /* Parent frame */
 363   VdbeFrame *pDelFrame;   /* List of frame objects to free on VM reset */
 364   int nFrame;             /* Number of frames in pFrame list */
 365   u32 expmask;            /* Binding to these vars invalidates VM */
 366   SubProgram *pProgram;   /* Linked list of all sub-programs used by VM */
 367   int nOnceFlag;          /* Size of array aOnceFlag[] */
 368   u8 *aOnceFlag;          /* Flags for OP_Once */
 369 };
 370
 371 /*
 372 ** The following are allowed values for Vdbe.magic
 373 */
 374 #define VDBE_MAGIC_INIT     0x26bceaa5    /* Building a VDBE program */
 375 #define VDBE_MAGIC_RUN      0xbdf20da3    /* VDBE is ready to execute */
 376 #define VDBE_MAGIC_HALT     0x519c2973    /* VDBE has completed execution */
 377 #define VDBE_MAGIC_DEAD     0xb606c3c8    /* The VDBE has been deallocated */
 378
 379 /*
 380 ** Function prototypes
 381 */
 382 void sqlite3VdbeFreeCursor(Vdbe *, VdbeCursor*);
 383 void sqliteVdbePopStack(Vdbe*,int);
 384 int sqlite3VdbeCursorMoveto(VdbeCursor*);
 385 #if defined(SQLITE_DEBUG) || defined(VDBE_PROFILE)
 386 void sqlite3VdbePrintOp(FILE*, int, Op*);
 387 #endif
 388 u32 sqlite3VdbeSerialTypeLen(u32);
 389 u32 sqlite3VdbeSerialType(Mem*, int);
 390 u32 sqlite3VdbeSerialPut(unsigned char*, int, Mem*, int);
 391 u32 sqlite3VdbeSerialGet(const unsigned char*, u32, Mem*);
 392 void sqlite3VdbeDeleteAuxData(VdbeFunc*, int);
 393
 394 int sqlite2BtreeKeyCompare(BtCursor *, const void *, int, int, int *);
 395 int sqlite3VdbeIdxKeyCompare(VdbeCursor*,UnpackedRecord*,int*);
 396 int sqlite3VdbeIdxRowid(sqlite3*, BtCursor *, i64 *);
 397 int sqlite3MemCompare(const Mem*, const Mem*, const CollSeq*);
 398 int sqlite3VdbeExec(Vdbe*);
 399 int sqlite3VdbeList(Vdbe*);
 400 int sqlite3VdbeHalt(Vdbe*);
 401 int sqlite3VdbeChangeEncoding(Mem *, int);
 402 int sqlite3VdbeMemTooBig(Mem*);
 403 int sqlite3VdbeMemCopy(Mem*, const Mem*);
 404 void sqlite3VdbeMemShallowCopy(Mem*, const Mem*, int);
 405 void sqlite3VdbeMemMove(Mem*, Mem*);
 406 int sqlite3VdbeMemNulTerminate(Mem*);
 407 int sqlite3VdbeMemSetStr(Mem*, const char*, int, u8, void(*)(void*));
 408 void sqlite3VdbeMemSetInt64(Mem*, i64);
 409 #ifdef SQLITE_OMIT_FLOATING_POINT
 410 # define sqlite3VdbeMemSetDouble sqlite3VdbeMemSetInt64
 411 #else
 412   void sqlite3VdbeMemSetDouble(Mem*, double);
 413 #endif
 414 void sqlite3VdbeMemSetNull(Mem*);
 415 void sqlite3VdbeMemSetZeroBlob(Mem*,int);
 416 void sqlite3VdbeMemSetRowSet(Mem*);
 417 int sqlite3VdbeMemMakeWriteable(Mem*);
 418 int sqlite3VdbeMemStringify(Mem*, int);
 419 i64 sqlite3VdbeIntValue(Mem*);
 420 int sqlite3VdbeMemIntegerify(Mem*);
 421 double sqlite3VdbeRealValue(Mem*);
 422 void sqlite3VdbeIntegerAffinity(Mem*);
 423 int sqlite3VdbeMemRealify(Mem*);
 424 int sqlite3VdbeMemNumerify(Mem*);
 425 int sqlite3VdbeMemFromBtree(BtCursor*,int,int,int,Mem*);
 426 void sqlite3VdbeMemRelease(Mem *p);
 427 void sqlite3VdbeMemReleaseExternal(Mem *p);
 428 #define VdbeMemRelease(X)  \
 429   if((X)->flags&(MEM_Agg|MEM_Dyn|MEM_RowSet|MEM_Frame)) \
 430     sqlite3VdbeMemReleaseExternal(X);
 431 int sqlite3VdbeMemFinalize(Mem*, FuncDef*);
 432 const char *sqlite3OpcodeName(int);
 433 int sqlite3VdbeMemGrow(Mem *pMem, int n, int preserve);
 434 int sqlite3VdbeCloseStatement(Vdbe *, int);
 435 void sqlite3VdbeFrameDelete(VdbeFrame*);
 436 int sqlite3VdbeFrameRestore(VdbeFrame *);
 437 void sqlite3VdbeMemStoreType(Mem *pMem);
 438 int sqlite3VdbeTransferError(Vdbe *p);
 439
 440 int sqlite3VdbeSorterInit(sqlite3 *, VdbeCursor *);
 441 void sqlite3VdbeSorterClose(sqlite3 *, VdbeCursor *);
 442 int sqlite3VdbeSorterRowkey(const VdbeCursor *, Mem *);
 443 int sqlite3VdbeSorterNext(sqlite3 *, const VdbeCursor *, int *);
 444 int sqlite3VdbeSorterRewind(sqlite3 *, const VdbeCursor *, int *);
 445 int sqlite3VdbeSorterWrite(sqlite3 *, const VdbeCursor *, Mem *);
 446 int sqlite3VdbeSorterCompare(const VdbeCursor *, Mem *, int *);
 447
 448 #if !defined(SQLITE_OMIT_SHARED_CACHE) && SQLITE_THREADSAFE>0
 449   void sqlite3VdbeEnter(Vdbe*);
 450   void sqlite3VdbeLeave(Vdbe*);
 451 #else
 452 # define sqlite3VdbeEnter(X)
 453 # define sqlite3VdbeLeave(X)
 454 #endif
 455
 456 #ifdef SQLITE_DEBUG
 457 void sqlite3VdbeMemAboutToChange(Vdbe*,Mem*);
 458 #endif
 459
 460 #ifndef SQLITE_OMIT_FOREIGN_KEY
 461 int sqlite3VdbeCheckFk(Vdbe *, int);
 462 #else
 463 # define sqlite3VdbeCheckFk(p,i) 0
 464 #endif
 465
 466 int sqlite3VdbeMemTranslate(Mem*, u8);
 467 #ifdef SQLITE_DEBUG
 468   void sqlite3VdbePrintSql(Vdbe*);
 469   void sqlite3VdbeMemPrettyPrint(Mem *pMem, char *zBuf);
 470 #endif
 471 int sqlite3VdbeMemHandleBom(Mem *pMem);
 472
 473 #ifndef SQLITE_OMIT_INCRBLOB
 474   int sqlite3VdbeMemExpandBlob(Mem *);
 475   #define ExpandBlob(P) (((P)->flags&MEM_Zero)?sqlite3VdbeMemExpandBlob(P):0)
 476 #else
 477   #define sqlite3VdbeMemExpandBlob(x) SQLITE_OK
 478   #define ExpandBlob(P) SQLITE_OK
 479 #endif
 480
 481 #endif /* !defined(_VDBEINT_H_) */