/*- * See the file LICENSE for redistribution information. * * Copyright (c) 1996, 1997, 1998, 1999 * Sleepycat Software. All rights reserved. */ /* * Copyright (c) 1990, 1993, 1994, 1995, 1996 * Keith Bostic. All rights reserved. */ /* * Copyright (c) 1990, 1993, 1994, 1995 * The Regents of the University of California. All rights reserved. * * This code is derived from software contributed to Berkeley by * Mike Olson. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * @(#)btree.h 11.8 (Sleepycat) 9/20/99 */ /* Forward structure declarations. */ struct __btree; typedef struct __btree BTREE; struct __cursor; typedef struct __cursor BTREE_CURSOR; struct __epg; typedef struct __epg EPG; struct __recno; typedef struct __recno RECNO; #define DEFMINKEYPAGE (2) #define ISINTERNAL(p) (TYPE(p) == P_IBTREE || TYPE(p) == P_IRECNO) #define ISLEAF(p) (TYPE(p) == P_LBTREE || TYPE(p) == P_LRECNO) /* * Flags to __bam_search() and __bam_rsearch(). * * Note, internal page searches must find the largest record less than key in * the tree so that descents work. Leaf page searches must find the smallest * record greater than key so that the returned index is the record's correct * position for insertion. * * The flags parameter to the search routines describes three aspects of the * search: the type of locking required (including if we're locking a pair of * pages), the item to return in the presence of duplicates and whether or not * to return deleted entries. To simplify both the mnemonic representation * and the code that checks for various cases, we construct a set of bitmasks. */ #define S_READ 0x00001 /* Read locks. */ #define S_WRITE 0x00002 /* Write locks. */ #define S_APPEND 0x00040 /* Append to the tree. */ #define S_DELNO 0x00080 /* Don't return deleted items. */ #define S_DUPFIRST 0x00100 /* Return first duplicate. */ #define S_DUPLAST 0x00200 /* Return last duplicate. */ #define S_EXACT 0x00400 /* Exact items only. */ #define S_PARENT 0x00800 /* Lock page pair. */ #define S_STACK 0x01000 /* Need a complete stack. */ #define S_PAST_EOF 0x02000 /* If doing insert search (or keyfirst * or keylast operations), or a split * on behalf of an insert, it's okay to * return an entry one past end-of-page. */ #define S_DELETE (S_WRITE | S_DUPFIRST | S_DELNO | S_EXACT | S_STACK) #define S_FIND (S_READ | S_DUPFIRST | S_DELNO) #define S_FIND_WR (S_WRITE | S_DUPFIRST | S_DELNO) #define S_INSERT (S_WRITE | S_DUPLAST | S_PAST_EOF | S_STACK) #define S_KEYFIRST (S_WRITE | S_DUPFIRST | S_PAST_EOF | S_STACK) #define S_KEYLAST (S_WRITE | S_DUPLAST | S_PAST_EOF | S_STACK) #define S_WRPAIR (S_WRITE | S_DUPLAST | S_PAST_EOF | S_PARENT) /* * Flags to __bam_iitem(). */ #define BI_DELETED 0x01 /* Key/data pair only placeholder. */ /* * Various routines pass around page references. A page reference is * a pointer to the page, and the indx indicates an item on the page. * Each page reference may include a lock. */ struct __epg { PAGE *page; /* The page. */ db_indx_t indx; /* The index on the page. */ DB_LOCK lock; /* The page's lock. */ db_lockmode_t lock_mode; /* The lock mode. */ }; /* * We maintain a stack of the pages that we're locking in the tree. Btree's * (currently) only save two levels of the tree at a time, so the default * stack is always large enough. Recno trees have to lock the entire tree to * do inserts/deletes, however. Grow the stack as necessary. */ #define BT_STK_CLR(c) \ ((c)->csp = (c)->sp) #define BT_STK_ENTER(c, pagep, page_indx, lock, mode, ret) do { \ if ((ret = \ (c)->csp == (c)->esp ? __bam_stkgrow(c) : 0) == 0) { \ (c)->csp->page = pagep; \ (c)->csp->indx = page_indx; \ (c)->csp->lock = lock; \ (c)->csp->lock_mode = mode; \ } \ } while (0) #define BT_STK_PUSH(c, pagep, page_indx, lock, mode, ret) do { \ BT_STK_ENTER(c, pagep, page_indx, lock, mode, ret); \ ++(c)->csp; \ } while (0) #define BT_STK_POP(c) \ ((c)->csp == (c)->stack ? NULL : --(c)->csp) /* * Arguments passed to __bam_ca_replace(). */ typedef enum { REPLACE_SETUP, REPLACE_SUCCESS, REPLACE_FAILED } ca_replace_arg; /* Arguments passed to __ram_ca(). */ typedef enum { CA_DELETE, CA_IAFTER, CA_IBEFORE } ca_recno_arg; /* Btree/Recno cursor. */ struct __cursor { /* Per-thread information: shared by btree/recno. */ EPG *sp; /* Stack pointer. */ EPG *csp; /* Current stack entry. */ EPG *esp; /* End stack pointer. */ EPG stack[5]; /* Per-thread information: btree private. */ PAGE *page; /* Cursor page. */ db_pgno_t pgno; /* Page. */ db_indx_t indx; /* Page item ref'd by the cursor. */ db_pgno_t dpgno; /* Duplicate page. */ db_indx_t dindx; /* Page item ref'd by the cursor. */ DB_LOCK lock; /* Cursor lock. */ db_lockmode_t lock_mode; /* Lock mode. */ /* Per-thread information: recno private. */ db_recno_t recno; /* Current record number. */ /* * Btree: * We set a flag in the cursor structure if the underlying object has * been deleted. It's not strictly necessary, we could get the same * information by looking at the page itself. * * Recno: * When renumbering recno databases during deletes, cursors referencing * "deleted" records end up positioned between two records, and so must * be specially adjusted on the next operation. */ #define C_DELETED 0x0001 /* Record was deleted. */ u_int32_t flags; }; /* * The in-memory, per-tree btree/recno data structure. */ struct __btree { /* Btree access method. */ db_pgno_t bt_lpgno; /* Last insert location. */ db_indx_t bt_ovflsize; /* Maximum key/data on-page size. */ db_pgno_t bt_meta; /* Database meta-data page. */ db_pgno_t bt_root; /* Database root page. */ u_int32_t bt_maxkey; /* Maximum keys per page. */ u_int32_t bt_minkey; /* Minimum keys per page. */ /* Btree comparison function. */ int (*bt_compare) __P((const DBT *, const DBT *)); /* Prefix function. */ size_t (*bt_prefix) __P((const DBT *, const DBT *)); /* Recno access method. */ int re_pad; /* Fixed-length padding byte. */ int re_delim; /* Variable-length delimiting byte. */ u_int32_t re_len; /* Length for fixed-length records. */ char *re_source; /* Source file name. */ /* * !!! * These fields are ignored as far as multi-threading is concerned. * There are no transaction semantics associated with backing files, * nor is there any thread protection. */ DB_FH re_fh; /* Source file handle. */ db_recno_t re_last; /* Last record number read. */ void *re_cmap; /* Current point in mapped space. */ void *re_smap; /* Start of mapped space. */ void *re_emap; /* End of mapped space. */ size_t re_msize; /* Size of mapped region. */ /* Recno input function. */ int (*re_irec) __P((DBC *, db_recno_t)); #define RECNO_EOF 0x01 /* EOF on backing source file. */ #define RECNO_MODIFIED 0x02 /* Tree was modified. */ u_int32_t flags; }; #include "btree_auto.h" #include "btree_ext.h" #include "db_am.h"