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Diffstat (limited to 'main/db1-ast/btree/btree.h')
| -rw-r--r-- | main/db1-ast/btree/btree.h | 391 |
1 files changed, 0 insertions, 391 deletions
diff --git a/main/db1-ast/btree/btree.h b/main/db1-ast/btree/btree.h deleted file mode 100644 index 1f4a9ec91..000000000 --- a/main/db1-ast/btree/btree.h +++ /dev/null @@ -1,391 +0,0 @@ -/*- - * Copyright (c) 1991, 1993, 1994 - * 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. All advertising materials mentioning features or use of this software - * must display the following acknowledgement: - * This product includes software developed by the University of - * California, Berkeley and its contributors. - * 4. 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 8.11 (Berkeley) 8/17/94 - */ - -/* Macros to set/clear/test flags. */ -#define F_SET(p, f) (p)->flags |= (f) -#define F_CLR(p, f) (p)->flags &= ~(f) -#define F_ISSET(p, f) ((p)->flags & (f)) - -#include <mpool.h> - -#define mpool_open __mpool_open -#define mpool_filter __mpool_filter -#define mpool_new __mpool_new -#define mpool_get __mpool_get -#define mpool_put __mpool_put -#define mpool_sync __mpool_sync -#define mpool_close __mpool_close - -#define DEFMINKEYPAGE (2) /* Minimum keys per page */ -#define MINCACHE (5) /* Minimum cached pages */ -#define MINPSIZE (512) /* Minimum page size */ - -/* - * Page 0 of a btree file contains a copy of the meta-data. This page is also - * used as an out-of-band page, i.e. page pointers that point to nowhere point - * to page 0. Page 1 is the root of the btree. - */ -#define P_INVALID 0 /* Invalid tree page number. */ -#define P_META 0 /* Tree metadata page number. */ -#define P_ROOT 1 /* Tree root page number. */ - -/* - * There are five page layouts in the btree: btree internal pages (BINTERNAL), - * btree leaf pages (BLEAF), recno internal pages (RINTERNAL), recno leaf pages - * (RLEAF) and overflow pages. All five page types have a page header (PAGE). - * This implementation requires that values within structures NOT be padded. - * (ANSI C permits random padding.) If your compiler pads randomly you'll have - * to do some work to get this package to run. - */ -typedef struct _page { - pgno_t pgno; /* this page's page number */ - pgno_t prevpg; /* left sibling */ - pgno_t nextpg; /* right sibling */ - -#define P_BINTERNAL 0x01 /* btree internal page */ -#define P_BLEAF 0x02 /* leaf page */ -#define P_OVERFLOW 0x04 /* overflow page */ -#define P_RINTERNAL 0x08 /* recno internal page */ -#define P_RLEAF 0x10 /* leaf page */ -#define P_TYPE 0x1f /* type mask */ -#define P_PRESERVE 0x20 /* never delete this chain of pages */ - u_int32_t flags; - - indx_t lower; /* lower bound of free space on page */ - indx_t upper; /* upper bound of free space on page */ - indx_t linp[1]; /* indx_t-aligned VAR. LENGTH DATA */ -} PAGE; - -/* First and next index. */ -#define BTDATAOFF \ - (sizeof(pgno_t) + sizeof(pgno_t) + sizeof(pgno_t) + \ - sizeof(u_int32_t) + sizeof(indx_t) + sizeof(indx_t)) -#define NEXTINDEX(p) (((p)->lower - BTDATAOFF) / sizeof(indx_t)) - -/* - * For pages other than overflow pages, there is an array of offsets into the - * rest of the page immediately following the page header. Each offset is to - * an item which is unique to the type of page. The h_lower offset is just - * past the last filled-in index. The h_upper offset is the first item on the - * page. Offsets are from the beginning of the page. - * - * If an item is too big to store on a single page, a flag is set and the item - * is a { page, size } pair such that the page is the first page of an overflow - * chain with size bytes of item. Overflow pages are simply bytes without any - * external structure. - * - * The page number and size fields in the items are pgno_t-aligned so they can - * be manipulated without copying. (This presumes that 32 bit items can be - * manipulated on this system.) - */ -#define LALIGN(n) (((n) + sizeof(pgno_t) - 1) & ~(sizeof(pgno_t) - 1)) -#define NOVFLSIZE (sizeof(pgno_t) + sizeof(u_int32_t)) - -/* - * For the btree internal pages, the item is a key. BINTERNALs are {key, pgno} - * pairs, such that the key compares less than or equal to all of the records - * on that page. For a tree without duplicate keys, an internal page with two - * consecutive keys, a and b, will have all records greater than or equal to a - * and less than b stored on the page associated with a. Duplicate keys are - * somewhat special and can cause duplicate internal and leaf page records and - * some minor modifications of the above rule. - */ -typedef struct _binternal { - u_int32_t ksize; /* key size */ - pgno_t pgno; /* page number stored on */ -#define P_BIGDATA 0x01 /* overflow data */ -#define P_BIGKEY 0x02 /* overflow key */ - u_char flags; - char bytes[1]; /* data */ -} BINTERNAL; - -/* Get the page's BINTERNAL structure at index indx. */ -#define GETBINTERNAL(pg, indx) \ - ((BINTERNAL *)((char *)(pg) + (pg)->linp[indx])) - -/* Get the number of bytes in the entry. */ -#define NBINTERNAL(len) \ - LALIGN(sizeof(u_int32_t) + sizeof(pgno_t) + sizeof(u_char) + (len)) - -/* Copy a BINTERNAL entry to the page. */ -#define WR_BINTERNAL(p, size, pgno, flags) { \ - *(u_int32_t *)p = size; \ - p += sizeof(u_int32_t); \ - *(pgno_t *)p = pgno; \ - p += sizeof(pgno_t); \ - *(u_char *)p = flags; \ - p += sizeof(u_char); \ -} - -/* - * For the recno internal pages, the item is a page number with the number of - * keys found on that page and below. - */ -typedef struct _rinternal { - recno_t nrecs; /* number of records */ - pgno_t pgno; /* page number stored below */ -} RINTERNAL; - -/* Get the page's RINTERNAL structure at index indx. */ -#define GETRINTERNAL(pg, indx) \ - ((RINTERNAL *)((char *)(pg) + (pg)->linp[indx])) - -/* Get the number of bytes in the entry. */ -#define NRINTERNAL \ - LALIGN(sizeof(recno_t) + sizeof(pgno_t)) - -/* Copy a RINTERNAL entry to the page. */ -#define WR_RINTERNAL(p, nrecs, pgno) { \ - *(recno_t *)p = nrecs; \ - p += sizeof(recno_t); \ - *(pgno_t *)p = pgno; \ -} - -/* For the btree leaf pages, the item is a key and data pair. */ -typedef struct _bleaf { - u_int32_t ksize; /* size of key */ - u_int32_t dsize; /* size of data */ - u_char flags; /* P_BIGDATA, P_BIGKEY */ - char bytes[1]; /* data */ -} BLEAF; - -/* Get the page's BLEAF structure at index indx. */ -#define GETBLEAF(pg, indx) \ - ((BLEAF *)((char *)(pg) + (pg)->linp[indx])) - -/* Get the number of bytes in the entry. */ -#define NBLEAF(p) NBLEAFDBT((p)->ksize, (p)->dsize) - -/* Get the number of bytes in the user's key/data pair. */ -#define NBLEAFDBT(ksize, dsize) \ - LALIGN(sizeof(u_int32_t) + sizeof(u_int32_t) + sizeof(u_char) + \ - (ksize) + (dsize)) - -/* Copy a BLEAF entry to the page. */ -#define WR_BLEAF(p, key, data, flags) { \ - *(u_int32_t *)p = key->size; \ - p += sizeof(u_int32_t); \ - *(u_int32_t *)p = data->size; \ - p += sizeof(u_int32_t); \ - *(u_char *)p = flags; \ - p += sizeof(u_char); \ - memmove(p, key->data, key->size); \ - p += key->size; \ - memmove(p, data->data, data->size); \ -} - -/* For the recno leaf pages, the item is a data entry. */ -typedef struct _rleaf { - u_int32_t dsize; /* size of data */ - u_char flags; /* P_BIGDATA */ - char bytes[1]; -} RLEAF; - -/* Get the page's RLEAF structure at index indx. */ -#define GETRLEAF(pg, indx) \ - ((RLEAF *)((char *)(pg) + (pg)->linp[indx])) - -/* Get the number of bytes in the entry. */ -#define NRLEAF(p) NRLEAFDBT((p)->dsize) - -/* Get the number of bytes from the user's data. */ -#define NRLEAFDBT(dsize) \ - LALIGN(sizeof(u_int32_t) + sizeof(u_char) + (dsize)) - -/* Copy a RLEAF entry to the page. */ -#define WR_RLEAF(p, data, flags) { \ - *(u_int32_t *)p = data->size; \ - p += sizeof(u_int32_t); \ - *(u_char *)p = flags; \ - p += sizeof(u_char); \ - memmove(p, data->data, data->size); \ -} - -/* - * A record in the tree is either a pointer to a page and an index in the page - * or a page number and an index. These structures are used as a cursor, stack - * entry and search returns as well as to pass records to other routines. - * - * One comment about searches. 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. - */ -typedef struct _epgno { - pgno_t pgno; /* the page number */ - indx_t index; /* the index on the page */ -} EPGNO; - -typedef struct _epg { - PAGE *page; /* the (pinned) page */ - indx_t index; /* the index on the page */ -} EPG; - -/* - * About cursors. The cursor (and the page that contained the key/data pair - * that it referenced) can be deleted, which makes things a bit tricky. If - * there are no duplicates of the cursor key in the tree (i.e. B_NODUPS is set - * or there simply aren't any duplicates of the key) we copy the key that it - * referenced when it's deleted, and reacquire a new cursor key if the cursor - * is used again. If there are duplicates keys, we move to the next/previous - * key, and set a flag so that we know what happened. NOTE: if duplicate (to - * the cursor) keys are added to the tree during this process, it is undefined - * if they will be returned or not in a cursor scan. - * - * The flags determine the possible states of the cursor: - * - * CURS_INIT The cursor references *something*. - * CURS_ACQUIRE The cursor was deleted, and a key has been saved so that - * we can reacquire the right position in the tree. - * CURS_AFTER, CURS_BEFORE - * The cursor was deleted, and now references a key/data pair - * that has not yet been returned, either before or after the - * deleted key/data pair. - * XXX - * This structure is broken out so that we can eventually offer multiple - * cursors as part of the DB interface. - */ -typedef struct _cursor { - EPGNO pg; /* B: Saved tree reference. */ - DBT key; /* B: Saved key, or key.data == NULL. */ - recno_t rcursor; /* R: recno cursor (1-based) */ - -#define CURS_ACQUIRE 0x01 /* B: Cursor needs to be reacquired. */ -#define CURS_AFTER 0x02 /* B: Unreturned cursor after key. */ -#define CURS_BEFORE 0x04 /* B: Unreturned cursor before key. */ -#define CURS_INIT 0x08 /* RB: Cursor initialized. */ - u_int8_t flags; -} CURSOR; - -/* - * The metadata of the tree. The nrecs field is used only by the RECNO code. - * This is because the btree doesn't really need it and it requires that every - * put or delete call modify the metadata. - */ -typedef struct _btmeta { - u_int32_t magic; /* magic number */ - u_int32_t version; /* version */ - u_int32_t psize; /* page size */ - u_int32_t free; /* page number of first free page */ - u_int32_t nrecs; /* R: number of records */ - -#define SAVEMETA (B_NODUPS | R_RECNO) - u_int32_t flags; /* bt_flags & SAVEMETA */ -} BTMETA; - -/* The in-memory btree/recno data structure. */ -typedef struct _btree { - MPOOL *bt_mp; /* memory pool cookie */ - - DB *bt_dbp; /* pointer to enclosing DB */ - - EPG bt_cur; /* current (pinned) page */ - PAGE *bt_pinned; /* page pinned across calls */ - - CURSOR bt_cursor; /* cursor */ - -#define BT_PUSH(t, p, i) { \ - t->bt_sp->pgno = p; \ - t->bt_sp->index = i; \ - ++t->bt_sp; \ -} -#define BT_POP(t) (t->bt_sp == t->bt_stack ? NULL : --t->bt_sp) -#define BT_CLR(t) (t->bt_sp = t->bt_stack) - EPGNO bt_stack[50]; /* stack of parent pages */ - EPGNO *bt_sp; /* current stack pointer */ - - DBT bt_rkey; /* returned key */ - DBT bt_rdata; /* returned data */ - - int bt_fd; /* tree file descriptor */ - - pgno_t bt_free; /* next free page */ - u_int32_t bt_psize; /* page size */ - indx_t bt_ovflsize; /* cut-off for key/data overflow */ - int bt_lorder; /* byte order */ - /* sorted order */ - enum { NOT, BACK, FORWARD } bt_order; - EPGNO bt_last; /* last insert */ - - /* B: key comparison function */ - int (*bt_cmp) __P((const DBT *, const DBT *)); - /* B: prefix comparison function */ - size_t (*bt_pfx) __P((const DBT *, const DBT *)); - /* R: recno input function */ - int (*bt_irec) __P((struct _btree *, recno_t)); - - FILE *bt_rfp; /* R: record FILE pointer */ - int bt_rfd; /* R: record file descriptor */ - - caddr_t bt_cmap; /* R: current point in mapped space */ - caddr_t bt_smap; /* R: start of mapped space */ - caddr_t bt_emap; /* R: end of mapped space */ - size_t bt_msize; /* R: size of mapped region. */ - - recno_t bt_nrecs; /* R: number of records */ - size_t bt_reclen; /* R: fixed record length */ - u_char bt_bval; /* R: delimiting byte/pad character */ - -/* - * NB: - * B_NODUPS and R_RECNO are stored on disk, and may not be changed. - */ -#define B_INMEM 0x00001 /* in-memory tree */ -#define B_METADIRTY 0x00002 /* need to write metadata */ -#define B_MODIFIED 0x00004 /* tree modified */ -#define B_NEEDSWAP 0x00008 /* if byte order requires swapping */ -#define B_RDONLY 0x00010 /* read-only tree */ - -#define B_NODUPS 0x00020 /* no duplicate keys permitted */ -#define R_RECNO 0x00080 /* record oriented tree */ - -#define R_CLOSEFP 0x00040 /* opened a file pointer */ -#define R_EOF 0x00100 /* end of input file reached. */ -#define R_FIXLEN 0x00200 /* fixed length records */ -#define R_MEMMAPPED 0x00400 /* memory mapped file. */ -#define R_INMEM 0x00800 /* in-memory file */ -#define R_MODIFIED 0x01000 /* modified file */ -#define R_RDONLY 0x02000 /* read-only file */ - -#define B_DB_LOCK 0x04000 /* DB_LOCK specified. */ -#define B_DB_SHMEM 0x08000 /* DB_SHMEM specified. */ -#define B_DB_TXN 0x10000 /* DB_TXN specified. */ - u_int32_t flags; -} BTREE; - -#include "extern.h" |