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Diffstat (limited to 'chromium/third_party/sqlite/sqlite-src-3240000/src/btreeInt.h')
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diff --git a/chromium/third_party/sqlite/sqlite-src-3240000/src/btreeInt.h b/chromium/third_party/sqlite/sqlite-src-3240000/src/btreeInt.h deleted file mode 100644 index d1e2c08d18f..00000000000 --- a/chromium/third_party/sqlite/sqlite-src-3240000/src/btreeInt.h +++ /dev/null @@ -1,704 +0,0 @@ -/* -** 2004 April 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 file implements an external (disk-based) database using BTrees. -** For a detailed discussion of BTrees, refer to -** -** Donald E. Knuth, THE ART OF COMPUTER PROGRAMMING, Volume 3: -** "Sorting And Searching", pages 473-480. Addison-Wesley -** Publishing Company, Reading, Massachusetts. -** -** The basic idea is that each page of the file contains N database -** entries and N+1 pointers to subpages. -** -** ---------------------------------------------------------------- -** | Ptr(0) | Key(0) | Ptr(1) | Key(1) | ... | Key(N-1) | Ptr(N) | -** ---------------------------------------------------------------- -** -** All of the keys on the page that Ptr(0) points to have values less -** than Key(0). All of the keys on page Ptr(1) and its subpages have -** values greater than Key(0) and less than Key(1). All of the keys -** on Ptr(N) and its subpages have values greater than Key(N-1). And -** so forth. -** -** Finding a particular key requires reading O(log(M)) pages from the -** disk where M is the number of entries in the tree. -** -** In this implementation, a single file can hold one or more separate -** BTrees. Each BTree is identified by the index of its root page. The -** key and data for any entry are combined to form the "payload". A -** fixed amount of payload can be carried directly on the database -** page. If the payload is larger than the preset amount then surplus -** bytes are stored on overflow pages. The payload for an entry -** and the preceding pointer are combined to form a "Cell". Each -** page has a small header which contains the Ptr(N) pointer and other -** information such as the size of key and data. -** -** FORMAT DETAILS -** -** The file is divided into pages. The first page is called page 1, -** the second is page 2, and so forth. A page number of zero indicates -** "no such page". The page size can be any power of 2 between 512 and 65536. -** Each page can be either a btree page, a freelist page, an overflow -** page, or a pointer-map page. -** -** The first page is always a btree page. The first 100 bytes of the first -** page contain a special header (the "file header") that describes the file. -** The format of the file header is as follows: -** -** OFFSET SIZE DESCRIPTION -** 0 16 Header string: "SQLite format 3\000" -** 16 2 Page size in bytes. (1 means 65536) -** 18 1 File format write version -** 19 1 File format read version -** 20 1 Bytes of unused space at the end of each page -** 21 1 Max embedded payload fraction (must be 64) -** 22 1 Min embedded payload fraction (must be 32) -** 23 1 Min leaf payload fraction (must be 32) -** 24 4 File change counter -** 28 4 Reserved for future use -** 32 4 First freelist page -** 36 4 Number of freelist pages in the file -** 40 60 15 4-byte meta values passed to higher layers -** -** 40 4 Schema cookie -** 44 4 File format of schema layer -** 48 4 Size of page cache -** 52 4 Largest root-page (auto/incr_vacuum) -** 56 4 1=UTF-8 2=UTF16le 3=UTF16be -** 60 4 User version -** 64 4 Incremental vacuum mode -** 68 4 Application-ID -** 72 20 unused -** 92 4 The version-valid-for number -** 96 4 SQLITE_VERSION_NUMBER -** -** All of the integer values are big-endian (most significant byte first). -** -** The file change counter is incremented when the database is changed -** This counter allows other processes to know when the file has changed -** and thus when they need to flush their cache. -** -** The max embedded payload fraction is the amount of the total usable -** space in a page that can be consumed by a single cell for standard -** B-tree (non-LEAFDATA) tables. A value of 255 means 100%. The default -** is to limit the maximum cell size so that at least 4 cells will fit -** on one page. Thus the default max embedded payload fraction is 64. -** -** If the payload for a cell is larger than the max payload, then extra -** payload is spilled to overflow pages. Once an overflow page is allocated, -** as many bytes as possible are moved into the overflow pages without letting -** the cell size drop below the min embedded payload fraction. -** -** The min leaf payload fraction is like the min embedded payload fraction -** except that it applies to leaf nodes in a LEAFDATA tree. The maximum -** payload fraction for a LEAFDATA tree is always 100% (or 255) and it -** not specified in the header. -** -** Each btree pages is divided into three sections: The header, the -** cell pointer array, and the cell content area. Page 1 also has a 100-byte -** file header that occurs before the page header. -** -** |----------------| -** | file header | 100 bytes. Page 1 only. -** |----------------| -** | page header | 8 bytes for leaves. 12 bytes for interior nodes -** |----------------| -** | cell pointer | | 2 bytes per cell. Sorted order. -** | array | | Grows downward -** | | v -** |----------------| -** | unallocated | -** | space | -** |----------------| ^ Grows upwards -** | cell content | | Arbitrary order interspersed with freeblocks. -** | area | | and free space fragments. -** |----------------| -** -** The page headers looks like this: -** -** OFFSET SIZE DESCRIPTION -** 0 1 Flags. 1: intkey, 2: zerodata, 4: leafdata, 8: leaf -** 1 2 byte offset to the first freeblock -** 3 2 number of cells on this page -** 5 2 first byte of the cell content area -** 7 1 number of fragmented free bytes -** 8 4 Right child (the Ptr(N) value). Omitted on leaves. -** -** The flags define the format of this btree page. The leaf flag means that -** this page has no children. The zerodata flag means that this page carries -** only keys and no data. The intkey flag means that the key is an integer -** which is stored in the key size entry of the cell header rather than in -** the payload area. -** -** The cell pointer array begins on the first byte after the page header. -** The cell pointer array contains zero or more 2-byte numbers which are -** offsets from the beginning of the page to the cell content in the cell -** content area. The cell pointers occur in sorted order. The system strives -** to keep free space after the last cell pointer so that new cells can -** be easily added without having to defragment the page. -** -** Cell content is stored at the very end of the page and grows toward the -** beginning of the page. -** -** Unused space within the cell content area is collected into a linked list of -** freeblocks. Each freeblock is at least 4 bytes in size. The byte offset -** to the first freeblock is given in the header. Freeblocks occur in -** increasing order. Because a freeblock must be at least 4 bytes in size, -** any group of 3 or fewer unused bytes in the cell content area cannot -** exist on the freeblock chain. A group of 3 or fewer free bytes is called -** a fragment. The total number of bytes in all fragments is recorded. -** in the page header at offset 7. -** -** SIZE DESCRIPTION -** 2 Byte offset of the next freeblock -** 2 Bytes in this freeblock -** -** Cells are of variable length. Cells are stored in the cell content area at -** the end of the page. Pointers to the cells are in the cell pointer array -** that immediately follows the page header. Cells is not necessarily -** contiguous or in order, but cell pointers are contiguous and in order. -** -** Cell content makes use of variable length integers. A variable -** length integer is 1 to 9 bytes where the lower 7 bits of each -** byte are used. The integer consists of all bytes that have bit 8 set and -** the first byte with bit 8 clear. The most significant byte of the integer -** appears first. A variable-length integer may not be more than 9 bytes long. -** As a special case, all 8 bytes of the 9th byte are used as data. This -** allows a 64-bit integer to be encoded in 9 bytes. -** -** 0x00 becomes 0x00000000 -** 0x7f becomes 0x0000007f -** 0x81 0x00 becomes 0x00000080 -** 0x82 0x00 becomes 0x00000100 -** 0x80 0x7f becomes 0x0000007f -** 0x8a 0x91 0xd1 0xac 0x78 becomes 0x12345678 -** 0x81 0x81 0x81 0x81 0x01 becomes 0x10204081 -** -** Variable length integers are used for rowids and to hold the number of -** bytes of key and data in a btree cell. -** -** The content of a cell looks like this: -** -** SIZE DESCRIPTION -** 4 Page number of the left child. Omitted if leaf flag is set. -** var Number of bytes of data. Omitted if the zerodata flag is set. -** var Number of bytes of key. Or the key itself if intkey flag is set. -** * Payload -** 4 First page of the overflow chain. Omitted if no overflow -** -** Overflow pages form a linked list. Each page except the last is completely -** filled with data (pagesize - 4 bytes). The last page can have as little -** as 1 byte of data. -** -** SIZE DESCRIPTION -** 4 Page number of next overflow page -** * Data -** -** Freelist pages come in two subtypes: trunk pages and leaf pages. The -** file header points to the first in a linked list of trunk page. Each trunk -** page points to multiple leaf pages. The content of a leaf page is -** unspecified. A trunk page looks like this: -** -** SIZE DESCRIPTION -** 4 Page number of next trunk page -** 4 Number of leaf pointers on this page -** * zero or more pages numbers of leaves -*/ -#include "sqliteInt.h" - - -/* The following value is the maximum cell size assuming a maximum page -** size give above. -*/ -#define MX_CELL_SIZE(pBt) ((int)(pBt->pageSize-8)) - -/* The maximum number of cells on a single page of the database. This -** assumes a minimum cell size of 6 bytes (4 bytes for the cell itself -** plus 2 bytes for the index to the cell in the page header). Such -** small cells will be rare, but they are possible. -*/ -#define MX_CELL(pBt) ((pBt->pageSize-8)/6) - -/* Forward declarations */ -typedef struct MemPage MemPage; -typedef struct BtLock BtLock; -typedef struct CellInfo CellInfo; - -/* -** This is a magic string that appears at the beginning of every -** SQLite database in order to identify the file as a real database. -** -** You can change this value at compile-time by specifying a -** -DSQLITE_FILE_HEADER="..." on the compiler command-line. The -** header must be exactly 16 bytes including the zero-terminator so -** the string itself should be 15 characters long. If you change -** the header, then your custom library will not be able to read -** databases generated by the standard tools and the standard tools -** will not be able to read databases created by your custom library. -*/ -#ifndef SQLITE_FILE_HEADER /* 123456789 123456 */ -# define SQLITE_FILE_HEADER "SQLite format 3" -#endif - -/* -** Page type flags. An ORed combination of these flags appear as the -** first byte of on-disk image of every BTree page. -*/ -#define PTF_INTKEY 0x01 -#define PTF_ZERODATA 0x02 -#define PTF_LEAFDATA 0x04 -#define PTF_LEAF 0x08 - -/* -** An instance of this object stores information about each a single database -** page that has been loaded into memory. The information in this object -** is derived from the raw on-disk page content. -** -** As each database page is loaded into memory, the pager allocats an -** instance of this object and zeros the first 8 bytes. (This is the -** "extra" information associated with each page of the pager.) -** -** Access to all fields of this structure is controlled by the mutex -** stored in MemPage.pBt->mutex. -*/ -struct MemPage { - u8 isInit; /* True if previously initialized. MUST BE FIRST! */ - u8 bBusy; /* Prevent endless loops on corrupt database files */ - u8 intKey; /* True if table b-trees. False for index b-trees */ - u8 intKeyLeaf; /* True if the leaf of an intKey table */ - Pgno pgno; /* Page number for this page */ - /* Only the first 8 bytes (above) are zeroed by pager.c when a new page - ** is allocated. All fields that follow must be initialized before use */ - u8 leaf; /* True if a leaf page */ - u8 hdrOffset; /* 100 for page 1. 0 otherwise */ - u8 childPtrSize; /* 0 if leaf==1. 4 if leaf==0 */ - u8 max1bytePayload; /* min(maxLocal,127) */ - u8 nOverflow; /* Number of overflow cell bodies in aCell[] */ - u16 maxLocal; /* Copy of BtShared.maxLocal or BtShared.maxLeaf */ - u16 minLocal; /* Copy of BtShared.minLocal or BtShared.minLeaf */ - u16 cellOffset; /* Index in aData of first cell pointer */ - u16 nFree; /* Number of free bytes on the page */ - u16 nCell; /* Number of cells on this page, local and ovfl */ - u16 maskPage; /* Mask for page offset */ - u16 aiOvfl[4]; /* Insert the i-th overflow cell before the aiOvfl-th - ** non-overflow cell */ - u8 *apOvfl[4]; /* Pointers to the body of overflow cells */ - BtShared *pBt; /* Pointer to BtShared that this page is part of */ - u8 *aData; /* Pointer to disk image of the page data */ - u8 *aDataEnd; /* One byte past the end of usable data */ - u8 *aCellIdx; /* The cell index area */ - u8 *aDataOfst; /* Same as aData for leaves. aData+4 for interior */ - DbPage *pDbPage; /* Pager page handle */ - u16 (*xCellSize)(MemPage*,u8*); /* cellSizePtr method */ - void (*xParseCell)(MemPage*,u8*,CellInfo*); /* btreeParseCell method */ -}; - -/* -** A linked list of the following structures is stored at BtShared.pLock. -** Locks are added (or upgraded from READ_LOCK to WRITE_LOCK) when a cursor -** is opened on the table with root page BtShared.iTable. Locks are removed -** from this list when a transaction is committed or rolled back, or when -** a btree handle is closed. -*/ -struct BtLock { - Btree *pBtree; /* Btree handle holding this lock */ - Pgno iTable; /* Root page of table */ - u8 eLock; /* READ_LOCK or WRITE_LOCK */ - BtLock *pNext; /* Next in BtShared.pLock list */ -}; - -/* Candidate values for BtLock.eLock */ -#define READ_LOCK 1 -#define WRITE_LOCK 2 - -/* A Btree handle -** -** A database connection contains a pointer to an instance of -** this object for every database file that it has open. This structure -** is opaque to the database connection. The database connection cannot -** see the internals of this structure and only deals with pointers to -** this structure. -** -** For some database files, the same underlying database cache might be -** shared between multiple connections. In that case, each connection -** has it own instance of this object. But each instance of this object -** points to the same BtShared object. The database cache and the -** schema associated with the database file are all contained within -** the BtShared object. -** -** All fields in this structure are accessed under sqlite3.mutex. -** The pBt pointer itself may not be changed while there exists cursors -** in the referenced BtShared that point back to this Btree since those -** cursors have to go through this Btree to find their BtShared and -** they often do so without holding sqlite3.mutex. -*/ -struct Btree { - sqlite3 *db; /* The database connection holding this btree */ - BtShared *pBt; /* Sharable content of this btree */ - u8 inTrans; /* TRANS_NONE, TRANS_READ or TRANS_WRITE */ - u8 sharable; /* True if we can share pBt with another db */ - u8 locked; /* True if db currently has pBt locked */ - u8 hasIncrblobCur; /* True if there are one or more Incrblob cursors */ - int wantToLock; /* Number of nested calls to sqlite3BtreeEnter() */ - int nBackup; /* Number of backup operations reading this btree */ - u32 iDataVersion; /* Combines with pBt->pPager->iDataVersion */ - Btree *pNext; /* List of other sharable Btrees from the same db */ - Btree *pPrev; /* Back pointer of the same list */ -#ifndef SQLITE_OMIT_SHARED_CACHE - BtLock lock; /* Object used to lock page 1 */ -#endif -}; - -/* -** Btree.inTrans may take one of the following values. -** -** If the shared-data extension is enabled, there may be multiple users -** of the Btree structure. At most one of these may open a write transaction, -** but any number may have active read transactions. -*/ -#define TRANS_NONE 0 -#define TRANS_READ 1 -#define TRANS_WRITE 2 - -/* -** An instance of this object represents a single database file. -** -** A single database file can be in use at the same time by two -** or more database connections. When two or more connections are -** sharing the same database file, each connection has it own -** private Btree object for the file and each of those Btrees points -** to this one BtShared object. BtShared.nRef is the number of -** connections currently sharing this database file. -** -** Fields in this structure are accessed under the BtShared.mutex -** mutex, except for nRef and pNext which are accessed under the -** global SQLITE_MUTEX_STATIC_MASTER mutex. The pPager field -** may not be modified once it is initially set as long as nRef>0. -** The pSchema field may be set once under BtShared.mutex and -** thereafter is unchanged as long as nRef>0. -** -** isPending: -** -** If a BtShared client fails to obtain a write-lock on a database -** table (because there exists one or more read-locks on the table), -** the shared-cache enters 'pending-lock' state and isPending is -** set to true. -** -** The shared-cache leaves the 'pending lock' state when either of -** the following occur: -** -** 1) The current writer (BtShared.pWriter) concludes its transaction, OR -** 2) The number of locks held by other connections drops to zero. -** -** while in the 'pending-lock' state, no connection may start a new -** transaction. -** -** This feature is included to help prevent writer-starvation. -*/ -struct BtShared { - Pager *pPager; /* The page cache */ - sqlite3 *db; /* Database connection currently using this Btree */ - BtCursor *pCursor; /* A list of all open cursors */ - MemPage *pPage1; /* First page of the database */ - u8 openFlags; /* Flags to sqlite3BtreeOpen() */ -#ifndef SQLITE_OMIT_AUTOVACUUM - u8 autoVacuum; /* True if auto-vacuum is enabled */ - u8 incrVacuum; /* True if incr-vacuum is enabled */ - u8 bDoTruncate; /* True to truncate db on commit */ -#endif - u8 inTransaction; /* Transaction state */ - u8 max1bytePayload; /* Maximum first byte of cell for a 1-byte payload */ -#ifdef SQLITE_HAS_CODEC - u8 optimalReserve; /* Desired amount of reserved space per page */ -#endif - u16 btsFlags; /* Boolean parameters. See BTS_* macros below */ - u16 maxLocal; /* Maximum local payload in non-LEAFDATA tables */ - u16 minLocal; /* Minimum local payload in non-LEAFDATA tables */ - u16 maxLeaf; /* Maximum local payload in a LEAFDATA table */ - u16 minLeaf; /* Minimum local payload in a LEAFDATA table */ - u32 pageSize; /* Total number of bytes on a page */ - u32 usableSize; /* Number of usable bytes on each page */ - int nTransaction; /* Number of open transactions (read + write) */ - u32 nPage; /* Number of pages in the database */ - void *pSchema; /* Pointer to space allocated by sqlite3BtreeSchema() */ - void (*xFreeSchema)(void*); /* Destructor for BtShared.pSchema */ - sqlite3_mutex *mutex; /* Non-recursive mutex required to access this object */ - Bitvec *pHasContent; /* Set of pages moved to free-list this transaction */ -#ifndef SQLITE_OMIT_SHARED_CACHE - int nRef; /* Number of references to this structure */ - BtShared *pNext; /* Next on a list of sharable BtShared structs */ - BtLock *pLock; /* List of locks held on this shared-btree struct */ - Btree *pWriter; /* Btree with currently open write transaction */ -#endif - u8 *pTmpSpace; /* Temp space sufficient to hold a single cell */ -}; - -/* -** Allowed values for BtShared.btsFlags -*/ -#define BTS_READ_ONLY 0x0001 /* Underlying file is readonly */ -#define BTS_PAGESIZE_FIXED 0x0002 /* Page size can no longer be changed */ -#define BTS_SECURE_DELETE 0x0004 /* PRAGMA secure_delete is enabled */ -#define BTS_OVERWRITE 0x0008 /* Overwrite deleted content with zeros */ -#define BTS_FAST_SECURE 0x000c /* Combination of the previous two */ -#define BTS_INITIALLY_EMPTY 0x0010 /* Database was empty at trans start */ -#define BTS_NO_WAL 0x0020 /* Do not open write-ahead-log files */ -#define BTS_EXCLUSIVE 0x0040 /* pWriter has an exclusive lock */ -#define BTS_PENDING 0x0080 /* Waiting for read-locks to clear */ - -/* -** An instance of the following structure is used to hold information -** about a cell. The parseCellPtr() function fills in this structure -** based on information extract from the raw disk page. -*/ -struct CellInfo { - i64 nKey; /* The key for INTKEY tables, or nPayload otherwise */ - u8 *pPayload; /* Pointer to the start of payload */ - u32 nPayload; /* Bytes of payload */ - u16 nLocal; /* Amount of payload held locally, not on overflow */ - u16 nSize; /* Size of the cell content on the main b-tree page */ -}; - -/* -** Maximum depth of an SQLite B-Tree structure. Any B-Tree deeper than -** this will be declared corrupt. This value is calculated based on a -** maximum database size of 2^31 pages a minimum fanout of 2 for a -** root-node and 3 for all other internal nodes. -** -** If a tree that appears to be taller than this is encountered, it is -** assumed that the database is corrupt. -*/ -#define BTCURSOR_MAX_DEPTH 20 - -/* -** A cursor is a pointer to a particular entry within a particular -** b-tree within a database file. -** -** The entry is identified by its MemPage and the index in -** MemPage.aCell[] of the entry. -** -** A single database file can be shared by two more database connections, -** but cursors cannot be shared. Each cursor is associated with a -** particular database connection identified BtCursor.pBtree.db. -** -** Fields in this structure are accessed under the BtShared.mutex -** found at self->pBt->mutex. -** -** skipNext meaning: -** eState==SKIPNEXT && skipNext>0: Next sqlite3BtreeNext() is no-op. -** eState==SKIPNEXT && skipNext<0: Next sqlite3BtreePrevious() is no-op. -** eState==FAULT: Cursor fault with skipNext as error code. -*/ -struct BtCursor { - u8 eState; /* One of the CURSOR_XXX constants (see below) */ - u8 curFlags; /* zero or more BTCF_* flags defined below */ - u8 curPagerFlags; /* Flags to send to sqlite3PagerGet() */ - u8 hints; /* As configured by CursorSetHints() */ - int skipNext; /* Prev() is noop if negative. Next() is noop if positive. - ** Error code if eState==CURSOR_FAULT */ - Btree *pBtree; /* The Btree to which this cursor belongs */ - Pgno *aOverflow; /* Cache of overflow page locations */ - void *pKey; /* Saved key that was cursor last known position */ - /* All fields above are zeroed when the cursor is allocated. See - ** sqlite3BtreeCursorZero(). Fields that follow must be manually - ** initialized. */ -#define BTCURSOR_FIRST_UNINIT pBt /* Name of first uninitialized field */ - BtShared *pBt; /* The BtShared this cursor points to */ - BtCursor *pNext; /* Forms a linked list of all cursors */ - CellInfo info; /* A parse of the cell we are pointing at */ - i64 nKey; /* Size of pKey, or last integer key */ - Pgno pgnoRoot; /* The root page of this tree */ - i8 iPage; /* Index of current page in apPage */ - u8 curIntKey; /* Value of apPage[0]->intKey */ - u16 ix; /* Current index for apPage[iPage] */ - u16 aiIdx[BTCURSOR_MAX_DEPTH-1]; /* Current index in apPage[i] */ - struct KeyInfo *pKeyInfo; /* Arg passed to comparison function */ - MemPage *pPage; /* Current page */ - MemPage *apPage[BTCURSOR_MAX_DEPTH-1]; /* Stack of parents of current page */ -}; - -/* -** Legal values for BtCursor.curFlags -*/ -#define BTCF_WriteFlag 0x01 /* True if a write cursor */ -#define BTCF_ValidNKey 0x02 /* True if info.nKey is valid */ -#define BTCF_ValidOvfl 0x04 /* True if aOverflow is valid */ -#define BTCF_AtLast 0x08 /* Cursor is pointing ot the last entry */ -#define BTCF_Incrblob 0x10 /* True if an incremental I/O handle */ -#define BTCF_Multiple 0x20 /* Maybe another cursor on the same btree */ - -/* -** Potential values for BtCursor.eState. -** -** CURSOR_INVALID: -** Cursor does not point to a valid entry. This can happen (for example) -** because the table is empty or because BtreeCursorFirst() has not been -** called. -** -** CURSOR_VALID: -** Cursor points to a valid entry. getPayload() etc. may be called. -** -** CURSOR_SKIPNEXT: -** Cursor is valid except that the Cursor.skipNext field is non-zero -** indicating that the next sqlite3BtreeNext() or sqlite3BtreePrevious() -** operation should be a no-op. -** -** CURSOR_REQUIRESEEK: -** The table that this cursor was opened on still exists, but has been -** modified since the cursor was last used. The cursor position is saved -** in variables BtCursor.pKey and BtCursor.nKey. When a cursor is in -** this state, restoreCursorPosition() can be called to attempt to -** seek the cursor to the saved position. -** -** CURSOR_FAULT: -** An unrecoverable error (an I/O error or a malloc failure) has occurred -** on a different connection that shares the BtShared cache with this -** cursor. The error has left the cache in an inconsistent state. -** Do nothing else with this cursor. Any attempt to use the cursor -** should return the error code stored in BtCursor.skipNext -*/ -#define CURSOR_VALID 0 -#define CURSOR_INVALID 1 -#define CURSOR_SKIPNEXT 2 -#define CURSOR_REQUIRESEEK 3 -#define CURSOR_FAULT 4 - -/* -** The database page the PENDING_BYTE occupies. This page is never used. -*/ -# define PENDING_BYTE_PAGE(pBt) PAGER_MJ_PGNO(pBt) - -/* -** These macros define the location of the pointer-map entry for a -** database page. The first argument to each is the number of usable -** bytes on each page of the database (often 1024). The second is the -** page number to look up in the pointer map. -** -** PTRMAP_PAGENO returns the database page number of the pointer-map -** page that stores the required pointer. PTRMAP_PTROFFSET returns -** the offset of the requested map entry. -** -** If the pgno argument passed to PTRMAP_PAGENO is a pointer-map page, -** then pgno is returned. So (pgno==PTRMAP_PAGENO(pgsz, pgno)) can be -** used to test if pgno is a pointer-map page. PTRMAP_ISPAGE implements -** this test. -*/ -#define PTRMAP_PAGENO(pBt, pgno) ptrmapPageno(pBt, pgno) -#define PTRMAP_PTROFFSET(pgptrmap, pgno) (5*(pgno-pgptrmap-1)) -#define PTRMAP_ISPAGE(pBt, pgno) (PTRMAP_PAGENO((pBt),(pgno))==(pgno)) - -/* -** The pointer map is a lookup table that identifies the parent page for -** each child page in the database file. The parent page is the page that -** contains a pointer to the child. Every page in the database contains -** 0 or 1 parent pages. (In this context 'database page' refers -** to any page that is not part of the pointer map itself.) Each pointer map -** entry consists of a single byte 'type' and a 4 byte parent page number. -** The PTRMAP_XXX identifiers below are the valid types. -** -** The purpose of the pointer map is to facility moving pages from one -** position in the file to another as part of autovacuum. When a page -** is moved, the pointer in its parent must be updated to point to the -** new location. The pointer map is used to locate the parent page quickly. -** -** PTRMAP_ROOTPAGE: The database page is a root-page. The page-number is not -** used in this case. -** -** PTRMAP_FREEPAGE: The database page is an unused (free) page. The page-number -** is not used in this case. -** -** PTRMAP_OVERFLOW1: The database page is the first page in a list of -** overflow pages. The page number identifies the page that -** contains the cell with a pointer to this overflow page. -** -** PTRMAP_OVERFLOW2: The database page is the second or later page in a list of -** overflow pages. The page-number identifies the previous -** page in the overflow page list. -** -** PTRMAP_BTREE: The database page is a non-root btree page. The page number -** identifies the parent page in the btree. -*/ -#define PTRMAP_ROOTPAGE 1 -#define PTRMAP_FREEPAGE 2 -#define PTRMAP_OVERFLOW1 3 -#define PTRMAP_OVERFLOW2 4 -#define PTRMAP_BTREE 5 - -/* A bunch of assert() statements to check the transaction state variables -** of handle p (type Btree*) are internally consistent. -*/ -#define btreeIntegrity(p) \ - assert( p->pBt->inTransaction!=TRANS_NONE || p->pBt->nTransaction==0 ); \ - assert( p->pBt->inTransaction>=p->inTrans ); - - -/* -** The ISAUTOVACUUM macro is used within balance_nonroot() to determine -** if the database supports auto-vacuum or not. Because it is used -** within an expression that is an argument to another macro -** (sqliteMallocRaw), it is not possible to use conditional compilation. -** So, this macro is defined instead. -*/ -#ifndef SQLITE_OMIT_AUTOVACUUM -#define ISAUTOVACUUM (pBt->autoVacuum) -#else -#define ISAUTOVACUUM 0 -#endif - - -/* -** This structure is passed around through all the sanity checking routines -** in order to keep track of some global state information. -** -** The aRef[] array is allocated so that there is 1 bit for each page in -** the database. As the integrity-check proceeds, for each page used in -** the database the corresponding bit is set. This allows integrity-check to -** detect pages that are used twice and orphaned pages (both of which -** indicate corruption). -*/ -typedef struct IntegrityCk IntegrityCk; -struct IntegrityCk { - BtShared *pBt; /* The tree being checked out */ - Pager *pPager; /* The associated pager. Also accessible by pBt->pPager */ - u8 *aPgRef; /* 1 bit per page in the db (see above) */ - Pgno nPage; /* Number of pages in the database */ - int mxErr; /* Stop accumulating errors when this reaches zero */ - int nErr; /* Number of messages written to zErrMsg so far */ - int mallocFailed; /* A memory allocation error has occurred */ - const char *zPfx; /* Error message prefix */ - int v1, v2; /* Values for up to two %d fields in zPfx */ - StrAccum errMsg; /* Accumulate the error message text here */ - u32 *heap; /* Min-heap used for analyzing cell coverage */ -}; - -/* -** Routines to read or write a two- and four-byte big-endian integer values. -*/ -#define get2byte(x) ((x)[0]<<8 | (x)[1]) -#define put2byte(p,v) ((p)[0] = (u8)((v)>>8), (p)[1] = (u8)(v)) -#define get4byte sqlite3Get4byte -#define put4byte sqlite3Put4byte - -/* -** get2byteAligned(), unlike get2byte(), requires that its argument point to a -** two-byte aligned address. get2bytea() is only used for accessing the -** cell addresses in a btree header. -*/ -#if SQLITE_BYTEORDER==4321 -# define get2byteAligned(x) (*(u16*)(x)) -#elif SQLITE_BYTEORDER==1234 && GCC_VERSION>=4008000 -# define get2byteAligned(x) __builtin_bswap16(*(u16*)(x)) -#elif SQLITE_BYTEORDER==1234 && MSVC_VERSION>=1300 -# define get2byteAligned(x) _byteswap_ushort(*(u16*)(x)) -#else -# define get2byteAligned(x) ((x)[0]<<8 | (x)[1]) -#endif |