diff -r 5f8e5adbbed9 -r 29cda98b007e engine/sqlite/src/vdbeInt.h --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/engine/sqlite/src/vdbeInt.h Thu Feb 25 14:29:19 2010 +0000 @@ -0,0 +1,427 @@ +/* +** 2003 September 6 +** +** The author disclaims copyright to this source code. In place of +** a legal notice, here is a blessing: +** +** May you do good and not evil. +** May you find forgiveness for yourself and forgive others. +** May you share freely, never taking more than you give. +** +************************************************************************* +** This is the header file for information that is private to the +** VDBE. This information used to all be at the top of the single +** source code file "vdbe.c". When that file became too big (over +** 6000 lines long) it was split up into several smaller files and +** this header information was factored out. +*/ +#ifndef _VDBEINT_H_ +#define _VDBEINT_H_ + +/* +** intToKey() and keyToInt() used to transform the rowid. But with +** the latest versions of the design they are no-ops. +*/ +#define keyToInt(X) (X) +#define intToKey(X) (X) + + +/* +** SQL is translated into a sequence of instructions to be +** executed by a virtual machine. Each instruction is an instance +** of the following structure. +*/ +typedef struct VdbeOp Op; + +/* +** Boolean values +*/ +typedef unsigned char Bool; + +/* +** A cursor is a pointer into a single BTree within a database file. +** The cursor can seek to a BTree entry with a particular key, or +** loop over all entries of the Btree. You can also insert new BTree +** entries or retrieve the key or data from the entry that the cursor +** is currently pointing to. +** +** Every cursor that the virtual machine has open is represented by an +** instance of the following structure. +** +** If the Cursor.isTriggerRow flag is set it means that this cursor is +** really a single row that represents the NEW or OLD pseudo-table of +** a row trigger. The data for the row is stored in Cursor.pData and +** the rowid is in Cursor.iKey. +*/ +struct Cursor { + BtCursor *pCursor; /* The cursor structure of the backend */ + int iDb; /* Index of cursor database in db->aDb[] (or -1) */ + i64 lastRowid; /* Last rowid from a Next or NextIdx operation */ + i64 nextRowid; /* Next rowid returned by OP_NewRowid */ + Bool zeroed; /* True if zeroed out and ready for reuse */ + Bool rowidIsValid; /* True if lastRowid is valid */ + Bool atFirst; /* True if pointing to first entry */ + Bool useRandomRowid; /* Generate new record numbers semi-randomly */ + Bool nullRow; /* True if pointing to a row with no data */ + Bool nextRowidValid; /* True if the nextRowid field is valid */ + Bool pseudoTable; /* This is a NEW or OLD pseudo-tables of a trigger */ + Bool deferredMoveto; /* A call to sqlite3BtreeMoveto() is needed */ + Bool isTable; /* True if a table requiring integer keys */ + Bool isIndex; /* True if an index containing keys only - no data */ + u8 bogusIncrKey; /* Something for pIncrKey to point to if pKeyInfo==0 */ + i64 movetoTarget; /* Argument to the deferred sqlite3BtreeMoveto() */ + Btree *pBt; /* Separate file holding temporary table */ + int nData; /* Number of bytes in pData */ + char *pData; /* Data for a NEW or OLD pseudo-table */ + i64 iKey; /* Key for the NEW or OLD pseudo-table row */ + u8 *pIncrKey; /* Pointer to pKeyInfo->incrKey */ + KeyInfo *pKeyInfo; /* Info about index keys needed by index cursors */ + int nField; /* Number of fields in the header */ + i64 seqCount; /* Sequence counter */ + sqlite3_vtab_cursor *pVtabCursor; /* The cursor for a virtual table */ + const sqlite3_module *pModule; /* Module for cursor pVtabCursor */ + + /* Cached information about the header for the data record that the + ** cursor is currently pointing to. Only valid if cacheValid is true. + ** aRow might point to (ephemeral) data for the current row, or it might + ** be NULL. + */ + int cacheStatus; /* Cache is valid if this matches Vdbe.cacheCtr */ + int payloadSize; /* Total number of bytes in the record */ + u32 *aType; /* Type values for all entries in the record */ + u32 *aOffset; /* Cached offsets to the start of each columns data */ + u8 *aRow; /* Data for the current row, if all on one page */ +}; +typedef struct Cursor Cursor; + +/* +** Number of bytes of string storage space available to each stack +** layer without having to malloc. NBFS is short for Number of Bytes +** For Strings. +*/ +#define NBFS 32 + +/* +** A value for Cursor.cacheValid that means the cache is always invalid. +*/ +#define CACHE_STALE 0 + +/* +** Internally, the vdbe manipulates nearly all SQL values as Mem +** structures. Each Mem struct may cache multiple representations (string, +** integer etc.) of the same value. A value (and therefore Mem structure) +** has the following properties: +** +** Each value has a manifest type. The manifest type of the value stored +** in a Mem struct is returned by the MemType(Mem*) macro. The type is +** one of SQLITE_NULL, SQLITE_INTEGER, SQLITE_REAL, SQLITE_TEXT or +** SQLITE_BLOB. +*/ +struct Mem { + union { + i64 i; /* Integer value. Or FuncDef* when flags==MEM_Agg */ + FuncDef *pDef; /* Used only when flags==MEM_Agg */ + } u; + double r; /* Real value */ + sqlite3 *db; /* The associated database connection */ + char *z; /* String or BLOB value */ + int n; /* Number of characters in string value, including '\0' */ + u16 flags; /* Some combination of MEM_Null, MEM_Str, MEM_Dyn, etc. */ + u8 type; /* One of SQLITE_NULL, SQLITE_TEXT, SQLITE_INTEGER, etc */ + u8 enc; /* SQLITE_UTF8, SQLITE_UTF16BE, SQLITE_UTF16LE */ + void (*xDel)(void *); /* If not null, call this function to delete Mem.z */ + char zShort[NBFS]; /* Space for short strings */ +}; +typedef struct Mem Mem; + +/* One or more of the following flags are set to indicate the validOK +** representations of the value stored in the Mem struct. +** +** If the MEM_Null flag is set, then the value is an SQL NULL value. +** No other flags may be set in this case. +** +** If the MEM_Str flag is set then Mem.z points at a string representation. +** Usually this is encoded in the same unicode encoding as the main +** database (see below for exceptions). If the MEM_Term flag is also +** set, then the string is nul terminated. The MEM_Int and MEM_Real +** flags may coexist with the MEM_Str flag. +** +** Multiple of these values can appear in Mem.flags. But only one +** at a time can appear in Mem.type. +*/ +#define MEM_Null 0x0001 /* Value is NULL */ +#define MEM_Str 0x0002 /* Value is a string */ +#define MEM_Int 0x0004 /* Value is an integer */ +#define MEM_Real 0x0008 /* Value is a real number */ +#define MEM_Blob 0x0010 /* Value is a BLOB */ + +/* Whenever Mem contains a valid string or blob representation, one of +** the following flags must be set to determine the memory management +** policy for Mem.z. The MEM_Term flag tells us whether or not the +** string is \000 or \u0000 terminated +*/ +#define MEM_Term 0x0020 /* String rep is nul terminated */ +#define MEM_Dyn 0x0040 /* Need to call sqliteFree() on Mem.z */ +#define MEM_Static 0x0080 /* Mem.z points to a static string */ +#define MEM_Ephem 0x0100 /* Mem.z points to an ephemeral string */ +#define MEM_Short 0x0200 /* Mem.z points to Mem.zShort */ +#define MEM_Agg 0x0400 /* Mem.z points to an agg function context */ +#define MEM_Zero 0x0800 /* Mem.i contains count of 0s appended to blob */ + +#ifdef SQLITE_OMIT_INCRBLOB + #undef MEM_Zero + #define MEM_Zero 0x0000 +#endif + + +/* A VdbeFunc is just a FuncDef (defined in sqliteInt.h) that contains +** additional information about auxiliary information bound to arguments +** of the function. This is used to implement the sqlite3_get_auxdata() +** and sqlite3_set_auxdata() APIs. The "auxdata" is some auxiliary data +** that can be associated with a constant argument to a function. This +** allows functions such as "regexp" to compile their constant regular +** expression argument once and reused the compiled code for multiple +** invocations. +*/ +struct VdbeFunc { + FuncDef *pFunc; /* The definition of the function */ + int nAux; /* Number of entries allocated for apAux[] */ + struct AuxData { + void *pAux; /* Aux data for the i-th argument */ + void (*xDelete)(void *); /* Destructor for the aux data */ + } apAux[1]; /* One slot for each function argument */ +}; +typedef struct VdbeFunc VdbeFunc; + +/* +** The "context" argument for a installable function. A pointer to an +** instance of this structure is the first argument to the routines used +** implement the SQL functions. +** +** There is a typedef for this structure in sqlite.h. So all routines, +** even the public interface to SQLite, can use a pointer to this structure. +** But this file is the only place where the internal details of this +** structure are known. +** +** This structure is defined inside of vdbeInt.h because it uses substructures +** (Mem) which are only defined there. +*/ +struct sqlite3_context { + FuncDef *pFunc; /* Pointer to function information. MUST BE FIRST */ + VdbeFunc *pVdbeFunc; /* Auxilary data, if created. */ + Mem s; /* The return value is stored here */ + Mem *pMem; /* Memory cell used to store aggregate context */ + u8 isError; /* Set to true for an error */ + CollSeq *pColl; /* Collating sequence */ +}; + +/* +** A Set structure is used for quick testing to see if a value +** is part of a small set. Sets are used to implement code like +** this: +** x.y IN ('hi','hoo','hum') +*/ +typedef struct Set Set; +struct Set { + Hash hash; /* A set is just a hash table */ + HashElem *prev; /* Previously accessed hash elemen */ +}; + +/* +** A FifoPage structure holds a single page of valves. Pages are arranged +** in a list. +*/ +typedef struct FifoPage FifoPage; +struct FifoPage { + int nSlot; /* Number of entries aSlot[] */ + int iWrite; /* Push the next value into this entry in aSlot[] */ + int iRead; /* Read the next value from this entry in aSlot[] */ + FifoPage *pNext; /* Next page in the fifo */ + i64 aSlot[1]; /* One or more slots for rowid values */ +}; + +/* +** The Fifo structure is typedef-ed in vdbeInt.h. But the implementation +** of that structure is private to this file. +** +** The Fifo structure describes the entire fifo. +*/ +typedef struct Fifo Fifo; +struct Fifo { + int nEntry; /* Total number of entries */ + FifoPage *pFirst; /* First page on the list */ + FifoPage *pLast; /* Last page on the list */ +}; + +/* +** A Context stores the last insert rowid, the last statement change count, +** and the current statement change count (i.e. changes since last statement). +** The current keylist is also stored in the context. +** Elements of Context structure type make up the ContextStack, which is +** updated by the ContextPush and ContextPop opcodes (used by triggers). +** The context is pushed before executing a trigger a popped when the +** trigger finishes. +*/ +typedef struct Context Context; +struct Context { + i64 lastRowid; /* Last insert rowid (sqlite3.lastRowid) */ + int nChange; /* Statement changes (Vdbe.nChanges) */ + Fifo sFifo; /* Records that will participate in a DELETE or UPDATE */ +}; + +/* +** An instance of the virtual machine. This structure contains the complete +** state of the virtual machine. +** +** The "sqlite3_stmt" structure pointer that is returned by sqlite3_compile() +** is really a pointer to an instance of this structure. +** +** The Vdbe.inVtabMethod variable is set to non-zero for the duration of +** any virtual table method invocations made by the vdbe program. It is +** set to 2 for xDestroy method calls and 1 for all other methods. This +** variable is used for two purposes: to allow xDestroy methods to execute +** "DROP TABLE" statements and to prevent some nasty side effects of +** malloc failure when SQLite is invoked recursively by a virtual table +** method function. +*/ +struct Vdbe { + sqlite3 *db; /* The whole database */ + Vdbe *pPrev,*pNext; /* Linked list of VDBEs with the same Vdbe.db */ + int nOp; /* Number of instructions in the program */ + int nOpAlloc; /* Number of slots allocated for aOp[] */ + Op *aOp; /* Space to hold the virtual machine's program */ + int nLabel; /* Number of labels used */ + int nLabelAlloc; /* Number of slots allocated in aLabel[] */ + int *aLabel; /* Space to hold the labels */ + Mem *aStack; /* The operand stack, except string values */ + Mem *pTos; /* Top entry in the operand stack */ + Mem **apArg; /* Arguments to currently executing user function */ + Mem *aColName; /* Column names to return */ + int nCursor; /* Number of slots in apCsr[] */ + Cursor **apCsr; /* One element of this array for each open cursor */ + int nVar; /* Number of entries in aVar[] */ + Mem *aVar; /* Values for the OP_Variable opcode. */ + char **azVar; /* Name of variables */ + int okVar; /* True if azVar[] has been initialized */ + int magic; /* Magic number for sanity checking */ + int nMem; /* Number of memory locations currently allocated */ + Mem *aMem; /* The memory locations */ + int nCallback; /* Number of callbacks invoked so far */ + int cacheCtr; /* Cursor row cache generation counter */ + Fifo sFifo; /* A list of ROWIDs */ + int contextStackTop; /* Index of top element in the context stack */ + int contextStackDepth; /* The size of the "context" stack */ + Context *contextStack; /* Stack used by opcodes ContextPush & ContextPop*/ + int pc; /* The program counter */ + int rc; /* Value to return */ + unsigned uniqueCnt; /* Used by OP_MakeRecord when P2!=0 */ + int errorAction; /* Recovery action to do in case of an error */ + int inTempTrans; /* True if temp database is transactioned */ + int returnStack[25]; /* Return address stack for OP_Gosub & OP_Return */ + int returnDepth; /* Next unused element in returnStack[] */ + int nResColumn; /* Number of columns in one row of the result set */ + char **azResColumn; /* Values for one row of result */ + int popStack; /* Pop the stack this much on entry to VdbeExec() */ + char *zErrMsg; /* Error message written here */ + u8 resOnStack; /* True if there are result values on the stack */ + u8 explain; /* True if EXPLAIN present on SQL command */ + u8 changeCntOn; /* True to update the change-counter */ + u8 aborted; /* True if ROLLBACK in another VM causes an abort */ + u8 expired; /* True if the VM needs to be recompiled */ + u8 minWriteFileFormat; /* Minimum file format for writable database files */ + u8 inVtabMethod; /* See comments above */ + int nChange; /* Number of db changes made since last reset */ + i64 startTime; /* Time when query started - used for profiling */ + int btreeMask; /* Bitmask of db->aDb[] entries referenced */ + BtreeMutexArray aMutex; /* An array of Btree used here and needing locks */ + int nSql; /* Number of bytes in zSql */ + char *zSql; /* Text of the SQL statement that generated this */ +#ifdef SQLITE_DEBUG + FILE *trace; /* Write an execution trace here, if not NULL */ +#endif + int openedStatement; /* True if this VM has opened a statement journal */ +#ifdef SQLITE_SSE + int fetchId; /* Statement number used by sqlite3_fetch_statement */ + int lru; /* Counter used for LRU cache replacement */ +#endif +}; + +/* +** The following are allowed values for Vdbe.magic +*/ +#define VDBE_MAGIC_INIT 0x26bceaa5 /* Building a VDBE program */ +#define VDBE_MAGIC_RUN 0xbdf20da3 /* VDBE is ready to execute */ +#define VDBE_MAGIC_HALT 0x519c2973 /* VDBE has completed execution */ +#define VDBE_MAGIC_DEAD 0xb606c3c8 /* The VDBE has been deallocated */ + +/* +** Function prototypes +*/ +void sqlite3VdbeFreeCursor(Vdbe *, Cursor*); +void sqliteVdbePopStack(Vdbe*,int); +int sqlite3VdbeCursorMoveto(Cursor*); +#if defined(SQLITE_DEBUG) || defined(VDBE_PROFILE) +void sqlite3VdbePrintOp(FILE*, int, Op*); +#endif +int sqlite3VdbeSerialTypeLen(u32); +u32 sqlite3VdbeSerialType(Mem*, int); +int sqlite3VdbeSerialPut(unsigned char*, int, Mem*, int); +int sqlite3VdbeSerialGet(const unsigned char*, u32, Mem*); +void sqlite3VdbeDeleteAuxData(VdbeFunc*, int); + +int sqlite2BtreeKeyCompare(BtCursor *, const void *, int, int, int *); +int sqlite3VdbeIdxKeyCompare(Cursor*,int,const unsigned char*,int*); +int sqlite3VdbeIdxRowid(BtCursor *, i64 *); +int sqlite3MemCompare(const Mem*, const Mem*, const CollSeq*); +int sqlite3VdbeRecordCompare(void*,int,const void*,int, const void*); +int sqlite3VdbeIdxRowidLen(const u8*); +int sqlite3VdbeExec(Vdbe*); +int sqlite3VdbeList(Vdbe*); +int sqlite3VdbeHalt(Vdbe*); +int sqlite3VdbeChangeEncoding(Mem *, int); +int sqlite3VdbeMemTooBig(Mem*); +int sqlite3VdbeMemCopy(Mem*, const Mem*); +void sqlite3VdbeMemShallowCopy(Mem*, const Mem*, int); +int sqlite3VdbeMemMove(Mem*, Mem*); +int sqlite3VdbeMemNulTerminate(Mem*); +int sqlite3VdbeMemSetStr(Mem*, const char*, int, u8, void(*)(void*)); +void sqlite3VdbeMemSetInt64(Mem*, i64); +void sqlite3VdbeMemSetDouble(Mem*, double); +void sqlite3VdbeMemSetNull(Mem*); +void sqlite3VdbeMemSetZeroBlob(Mem*,int); +int sqlite3VdbeMemMakeWriteable(Mem*); +int sqlite3VdbeMemDynamicify(Mem*); +int sqlite3VdbeMemStringify(Mem*, int); +i64 sqlite3VdbeIntValue(Mem*); +int sqlite3VdbeMemIntegerify(Mem*); +double sqlite3VdbeRealValue(Mem*); +void sqlite3VdbeIntegerAffinity(Mem*); +int sqlite3VdbeMemRealify(Mem*); +int sqlite3VdbeMemNumerify(Mem*); +int sqlite3VdbeMemFromBtree(BtCursor*,int,int,int,Mem*); +void sqlite3VdbeMemRelease(Mem *p); +int sqlite3VdbeMemFinalize(Mem*, FuncDef*); +const char *sqlite3OpcodeName(int); + +#ifndef NDEBUG + void sqlite3VdbeMemSanity(Mem*); + int sqlite3VdbeOpcodeNoPush(u8); +#endif +int sqlite3VdbeMemTranslate(Mem*, u8); +#ifdef SQLITE_DEBUG + void sqlite3VdbePrintSql(Vdbe*); + void sqlite3VdbeMemPrettyPrint(Mem *pMem, char *zBuf); +#endif +int sqlite3VdbeMemHandleBom(Mem *pMem); +void sqlite3VdbeFifoInit(Fifo*); +int sqlite3VdbeFifoPush(Fifo*, i64); +int sqlite3VdbeFifoPop(Fifo*, i64*); +void sqlite3VdbeFifoClear(Fifo*); + +#ifndef SQLITE_OMIT_INCRBLOB + int sqlite3VdbeMemExpandBlob(Mem *); +#else + #define sqlite3VdbeMemExpandBlob(x) SQLITE_OK +#endif + +#endif /* !defined(_VDBEINT_H_) */