--- /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_) */