src/btree.h

   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 ** This header file defines the interface that the sqlite B-Tree file
  13 ** subsystem.  See comments in the source code for a detailed description
  14 ** of what each interface routine does.
  15 */
  16 #ifndef _BTREE_H_
  17 #define _BTREE_H_
  18
  19 /* TODO: This definition is just included so other modules compile. It
  20 ** needs to be revisited.
  21 */
  22 #define SQLITE_N_BTREE_META 10
  23
  24 /*
  25 ** If defined as non-zero, auto-vacuum is enabled by default. Otherwise
  26 ** it must be turned on for each database using "PRAGMA auto_vacuum = 1".
  27 */
  28 #ifndef SQLITE_DEFAULT_AUTOVACUUM
  29   #define SQLITE_DEFAULT_AUTOVACUUM 0
  30 #endif
  31
  32 #define BTREE_AUTOVACUUM_NONE 0        /* Do not do auto-vacuum */
  33 #define BTREE_AUTOVACUUM_FULL 1        /* Do full auto-vacuum */
  34 #define BTREE_AUTOVACUUM_INCR 2        /* Incremental vacuum */
  35
  36 /*
  37 ** Forward declarations of structure
  38 */
  39 typedef struct Btree Btree;
  40 typedef struct BtCursor BtCursor;
  41 typedef struct BtShared BtShared;
  42
  43
  44 int sqlite3BtreeOpen(
  45   sqlite3_vfs *pVfs,       /* VFS to use with this b-tree */
  46   const char *zFilename,   /* Name of database file to open */
  47   sqlite3 *db,             /* Associated database connection */
  48   Btree **ppBtree,         /* Return open Btree* here */
  49   int flags,               /* Flags */
  50   int vfsFlags             /* Flags passed through to VFS open */
  51 );
  52
  53 /* The flags parameter to sqlite3BtreeOpen can be the bitwise or of the
  54 ** following values.
  55 **
  56 ** NOTE:  These values must match the corresponding PAGER_ values in
  57 ** pager.h.
  58 */
  59 #define BTREE_OMIT_JOURNAL  1  /* Do not create or use a rollback journal */
  60 #define BTREE_MEMORY        2  /* This is an in-memory DB */
  61 #define BTREE_SINGLE        4  /* The file contains at most 1 b-tree */
  62 #define BTREE_UNORDERED     8  /* Use of a hash implementation is OK */
  63
  64 int sqlite3BtreeClose(Btree*);
  65 int sqlite3BtreeSetCacheSize(Btree*,int);
  66 int sqlite3BtreeSetMmapLimit(Btree*,sqlite3_int64);
  67 int sqlite3BtreeSetSafetyLevel(Btree*,int,int,int);
  68 int sqlite3BtreeSyncDisabled(Btree*);
  69 int sqlite3BtreeSetPageSize(Btree *p, int nPagesize, int nReserve, int eFix);
  70 int sqlite3BtreeGetPageSize(Btree*);
  71 int sqlite3BtreeMaxPageCount(Btree*,int);
  72 u32 sqlite3BtreeLastPage(Btree*);
  73 int sqlite3BtreeSecureDelete(Btree*,int);
  74 int sqlite3BtreeGetReserve(Btree*);
  75 #if defined(SQLITE_HAS_CODEC) || defined(SQLITE_DEBUG)
  76 int sqlite3BtreeGetReserveNoMutex(Btree *p);
  77 #endif
  78 int sqlite3BtreeSetAutoVacuum(Btree *, int);
  79 int sqlite3BtreeGetAutoVacuum(Btree *);
  80 int sqlite3BtreeBeginTrans(Btree*,int);
  81 int sqlite3BtreeCommitPhaseOne(Btree*, const char *zMaster);
  82 int sqlite3BtreeCommitPhaseTwo(Btree*, int);
  83 int sqlite3BtreeCommit(Btree*);
  84 int sqlite3BtreeRollback(Btree*,int);
  85 int sqlite3BtreeBeginStmt(Btree*,int);
  86 int sqlite3BtreeCreateTable(Btree*, int*, int flags);
  87 int sqlite3BtreeIsInTrans(Btree*);
  88 int sqlite3BtreeIsInReadTrans(Btree*);
  89 int sqlite3BtreeIsInBackup(Btree*);
  90 void *sqlite3BtreeSchema(Btree *, int, void(*)(void *));
  91 int sqlite3BtreeSchemaLocked(Btree *pBtree);
  92 int sqlite3BtreeLockTable(Btree *pBtree, int iTab, u8 isWriteLock);
  93 int sqlite3BtreeSavepoint(Btree *, int, int);
  94
  95 const char *sqlite3BtreeGetFilename(Btree *);
  96 const char *sqlite3BtreeGetJournalname(Btree *);
  97 int sqlite3BtreeCopyFile(Btree *, Btree *);
  98
  99 int sqlite3BtreeIncrVacuum(Btree *);
 100
 101 /* The flags parameter to sqlite3BtreeCreateTable can be the bitwise OR
 102 ** of the flags shown below.
 103 **
 104 ** Every SQLite table must have either BTREE_INTKEY or BTREE_BLOBKEY set.
 105 ** With BTREE_INTKEY, the table key is a 64-bit integer and arbitrary data
 106 ** is stored in the leaves.  (BTREE_INTKEY is used for SQL tables.)  With
 107 ** BTREE_BLOBKEY, the key is an arbitrary BLOB and no content is stored
 108 ** anywhere - the key is the content.  (BTREE_BLOBKEY is used for SQL
 109 ** indices.)
 110 */
 111 #define BTREE_INTKEY     1    /* Table has only 64-bit signed integer keys */
 112 #define BTREE_BLOBKEY    2    /* Table has keys only - no data */
 113
 114 int sqlite3BtreeDropTable(Btree*, int, int*);
 115 int sqlite3BtreeClearTable(Btree*, int, int*);
 116 void sqlite3BtreeTripAllCursors(Btree*, int);
 117
 118 void sqlite3BtreeGetMeta(Btree *pBtree, int idx, u32 *pValue);
 119 int sqlite3BtreeUpdateMeta(Btree*, int idx, u32 value);
 120
 121 int sqlite3BtreeNewDb(Btree *p);
 122
 123 /*
 124 ** The second parameter to sqlite3BtreeGetMeta or sqlite3BtreeUpdateMeta
 125 ** should be one of the following values. The integer values are assigned
 126 ** to constants so that the offset of the corresponding field in an
 127 ** SQLite database header may be found using the following formula:
 128 **
 129 **   offset = 36 + (idx * 4)
 130 **
 131 ** For example, the free-page-count field is located at byte offset 36 of
 132 ** the database file header. The incr-vacuum-flag field is located at
 133 ** byte offset 64 (== 36+4*7).
 134 */
 135 #define BTREE_FREE_PAGE_COUNT     0
 136 #define BTREE_SCHEMA_VERSION      1
 137 #define BTREE_FILE_FORMAT         2
 138 #define BTREE_DEFAULT_CACHE_SIZE  3
 139 #define BTREE_LARGEST_ROOT_PAGE   4
 140 #define BTREE_TEXT_ENCODING       5
 141 #define BTREE_USER_VERSION        6
 142 #define BTREE_INCR_VACUUM         7
 143 #define BTREE_APPLICATION_ID      8
 144
 145 /*
 146 ** Values that may be OR'd together to form the second argument of an
 147 ** sqlite3BtreeCursorHints() call.
 148 */
 149 #define BTREE_BULKLOAD 0x00000001
 150
 151 int sqlite3BtreeCursor(
 152   Btree*,                              /* BTree containing table to open */
 153   int iTable,                          /* Index of root page */
 154   int wrFlag,                          /* 1 for writing.  0 for read-only */
 155   struct KeyInfo*,                     /* First argument to compare function */
 156   BtCursor *pCursor                    /* Space to write cursor structure */
 157 );
 158 int sqlite3BtreeCursorSize(void);
 159 void sqlite3BtreeCursorZero(BtCursor*);
 160
 161 int sqlite3BtreeCloseCursor(BtCursor*);
 162 int sqlite3BtreeMovetoUnpacked(
 163   BtCursor*,
 164   UnpackedRecord *pUnKey,
 165   i64 intKey,
 166   int bias,
 167   int *pRes
 168 );
 169 int sqlite3BtreeCursorHasMoved(BtCursor*, int*);
 170 int sqlite3BtreeDelete(BtCursor*);
 171 int sqlite3BtreeInsert(BtCursor*, const void *pKey, i64 nKey,
 172                                   const void *pData, int nData,
 173                                   int nZero, int bias, int seekResult);
 174 int sqlite3BtreeFirst(BtCursor*, int *pRes);
 175 int sqlite3BtreeLast(BtCursor*, int *pRes);
 176 int sqlite3BtreeNext(BtCursor*, int *pRes);
 177 int sqlite3BtreeEof(BtCursor*);
 178 int sqlite3BtreePrevious(BtCursor*, int *pRes);
 179 int sqlite3BtreeKeySize(BtCursor*, i64 *pSize);
 180 int sqlite3BtreeKey(BtCursor*, u32 offset, u32 amt, void*);
 181 const void *sqlite3BtreeKeyFetch(BtCursor*, int *pAmt);
 182 const void *sqlite3BtreeDataFetch(BtCursor*, int *pAmt);
 183 int sqlite3BtreeDataSize(BtCursor*, u32 *pSize);
 184 int sqlite3BtreeData(BtCursor*, u32 offset, u32 amt, void*);
 185 void sqlite3BtreeSetCachedRowid(BtCursor*, sqlite3_int64);
 186 sqlite3_int64 sqlite3BtreeGetCachedRowid(BtCursor*);
 187
 188 char *sqlite3BtreeIntegrityCheck(Btree*, int *aRoot, int nRoot, int, int*);
 189 struct Pager *sqlite3BtreePager(Btree*);
 190
 191 int sqlite3BtreePutData(BtCursor*, u32 offset, u32 amt, void*);
 192 void sqlite3BtreeCacheOverflow(BtCursor *);
 193 void sqlite3BtreeClearCursor(BtCursor *);
 194 int sqlite3BtreeSetVersion(Btree *pBt, int iVersion);
 195 void sqlite3BtreeCursorHints(BtCursor *, unsigned int mask);
 196
 197 #ifndef NDEBUG
 198 int sqlite3BtreeCursorIsValid(BtCursor*);
 199 #endif
 200
 201 #ifndef SQLITE_OMIT_BTREECOUNT
 202 int sqlite3BtreeCount(BtCursor *, i64 *);
 203 #endif
 204
 205 #ifdef SQLITE_TEST
 206 int sqlite3BtreeCursorInfo(BtCursor*, int*, int);
 207 void sqlite3BtreeCursorList(Btree*);
 208 #endif
 209
 210 #ifndef SQLITE_OMIT_WAL
 211   int sqlite3BtreeCheckpoint(Btree*, int, int *, int *);
 212 #endif
 213
 214 /*
 215 ** If we are not using shared cache, then there is no need to
 216 ** use mutexes to access the BtShared structures.  So make the
 217 ** Enter and Leave procedures no-ops.
 218 */
 219 #ifndef SQLITE_OMIT_SHARED_CACHE
 220   void sqlite3BtreeEnter(Btree*);
 221   void sqlite3BtreeEnterAll(sqlite3*);
 222 #else
 223 # define sqlite3BtreeEnter(X)
 224 # define sqlite3BtreeEnterAll(X)
 225 #endif
 226
 227 #if !defined(SQLITE_OMIT_SHARED_CACHE) && SQLITE_THREADSAFE
 228   int sqlite3BtreeSharable(Btree*);
 229   void sqlite3BtreeLeave(Btree*);
 230   void sqlite3BtreeEnterCursor(BtCursor*);
 231   void sqlite3BtreeLeaveCursor(BtCursor*);
 232   void sqlite3BtreeLeaveAll(sqlite3*);
 233 #ifndef NDEBUG
 234   /* These routines are used inside assert() statements only. */
 235   int sqlite3BtreeHoldsMutex(Btree*);
 236   int sqlite3BtreeHoldsAllMutexes(sqlite3*);
 237   int sqlite3SchemaMutexHeld(sqlite3*,int,Schema*);
 238 #endif
 239 #else
 240
 241 # define sqlite3BtreeSharable(X) 0
 242 # define sqlite3BtreeLeave(X)
 243 # define sqlite3BtreeEnterCursor(X)
 244 # define sqlite3BtreeLeaveCursor(X)
 245 # define sqlite3BtreeLeaveAll(X)
 246
 247 # define sqlite3BtreeHoldsMutex(X) 1
 248 # define sqlite3BtreeHoldsAllMutexes(X) 1
 249 # define sqlite3SchemaMutexHeld(X,Y,Z) 1
 250 #endif
 251
 252
 253 #endif /* _BTREE_H_ */