diff options
author | Ulrich Drepper <drepper@redhat.com> | 1997-08-27 20:26:10 +0000 |
---|---|---|
committer | Ulrich Drepper <drepper@redhat.com> | 1997-08-27 20:26:10 +0000 |
commit | 92f1da4da04a7a86ddee91be5eaf0b10c333ac64 (patch) | |
tree | 2a10ce9e4e407e7e5b5ca092ca0947d234b5ff60 /db2/include/db_page.h | |
parent | 22be878ecbc66606371bd33258f56e6711e6ba7a (diff) | |
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Update.cvs/libc-ud-970827
1997-08-10 19:17 Philip Blundell <Philip.Blundell@pobox.com>
* nss/nss_db/db-XXX.c: Include <db_185.h> not <db.h>. Somebody
should update this to use the new db API.
* nss/nss_db/db-netgrp.c: Likewise.
* nss/nss_db/db-alias.c: Likewise.
* db2/Makefile: Makefile for db-2.x in glibc.
1997-08-27 21:20 Ulrich Drepper <drepper@cygnus.com>
* csu/Makefile (before-compile): New goal. Make sure abi-tag.h
is generated.
[$(elf)=yes] (asm-CPPFLAGS): Make sure abi-tag.h file can be found.
* Makeconfig [$(build-omitfp)=yes] (CFLAGS-.o): Add
-D__USE_STRING_INLINES.
* string/string.f: Move strnlen optimization after inclusion of
<bits/string.h>. Include <bits/string.h> only if __USE_STRING_INLINES
is defined.
* sysdeps/generic/memcpy.c: Undef memcpy to allow macro of this name
in <bits/string.h>.
* sysdeps/generic/memset.c: Likewise.
* sysdeps/i386/string.h: i386 optimized string functions.
* sysdeps/i386/i486string.h: i486+ optimized string functions.
* Makefile (subdirs): Change db to db2.
* shlib-versions: Bump libdb verion number to 3.
* include/db.h: Include from db2 directory.
* include/db_185.h: New file.
* sysdeps/i386/Makefile [$(subdirs)=db2] (CPPFLAGS): Add macros
to provide spinlock information for db2.
* sysdeps/m68k/m68020/Makefile: New file. Likewise.
* sysdeps/sparc/Makefile: New file. Likewise.
* sysdeps/unix/sysv/linux/Makefile [$(subdirs)=db2] (CPPFLAGS):
Add -DHAVE_LLSEEK.
* db2/config.h: Hand-edited config file for db2 in glibc.
* db2/compat.h: New file from db-2.3.4.
* db2/db.h: Likewise.
* db2/db_185.h: Likewise.
* db2/db_int.h: Likewise.
* db2/makedb.c: Likewise.
* db2/btree/bt_close.c: Likewise.
* db2/btree/bt_compare.c: Likewise.
* db2/btree/bt_conv.c: Likewise.
* db2/btree/bt_cursor.c: Likewise.
* db2/btree/bt_delete.c: Likewise.
* db2/btree/bt_open.c: Likewise.
* db2/btree/bt_page.c: Likewise.
* db2/btree/bt_put.c: Likewise.
* db2/btree/bt_rec.c: Likewise.
* db2/btree/bt_recno.c: Likewise.
* db2/btree/btree_auto.c: Likewise.
* db2/btree/bt_rsearch.c: Likewise.
* db2/btree/bt_search.c: Likewise.
* db2/btree/bt_split.c: Likewise.
* db2/btree/bt_stat.c: Likewise.
* db2/btree/btree.src: Likewise.
* db2/common/db_appinit.c: Likewise.
* db2/common/db_err.c: Likewise.
* db2/common/db_byteorder.c: Likewise.
* db2/common/db_apprec.c: Likewise.
* db2/common/db_salloc.c: Likewise.
* db2/common/db_log2.c: Likewise.
* db2/common/db_region.c: Likewise.
* db2/common/db_shash.c: Likewise.
* db2/db/db.c: Likewise.
* db2/db/db.src: Likewise.
* db2/db/db_conv.c: Likewise.
* db2/db/db_dispatch.c: Likewise.
* db2/db/db_dup.c: Likewise.
* db2/db/db_overflow.c: Likewise.
* db2/db/db_pr.c: Likewise.
* db2/db/db_rec.c: Likewise.
* db2/db/db_ret.c: Likewise.
* db2/db/db_thread.c: Likewise.
* db2/db/db_auto.c: Likewise.
* db2/db185/db185.c: Likewise.
* db2/db185/db185_int.h: Likewise.
* db2/dbm/dbm.c: Likewise.
* db2/hash/hash.c: Likewise.
* db2/hash/hash.src: Likewise.
* db2/hash/hash_page.c: Likewise.
* db2/hash/hash_conv.c: Likewise.
* db2/hash/hash_debug.c: Likewise.
* db2/hash/hash_stat.c: Likewise.
* db2/hash/hash_rec.c: Likewise.
* db2/hash/hash_dup.c: Likewise.
* db2/hash/hash_func.c: Likewise.
* db2/hash/hash_auto.c: Likewise.
* db2/include/mp.h: Likewise.
* db2/include/btree.h: Likewise.
* db2/include/db.h.src: Likewise.
* db2/include/db_int.h.src: Likewise.
* db2/include/db_shash.h: Likewise.
* db2/include/db_swap.h: Likewise.
* db2/include/db_185.h.src: Likewise.
* db2/include/txn.h: Likewise.
* db2/include/db_am.h: Likewise.
* db2/include/shqueue.h: Likewise.
* db2/include/hash.h: Likewise.
* db2/include/db_dispatch.h: Likewise.
* db2/include/lock.h: Likewise.
* db2/include/db_page.h: Likewise.
* db2/include/log.h: Likewise.
* db2/include/db_auto.h: Likewise.
* db2/include/btree_auto.h: Likewise.
* db2/include/hash_auto.h: Likewise.
* db2/include/log_auto.h: Likewise.
* db2/include/txn_auto.h: Likewise.
* db2/include/db_ext.h: Likewise.
* db2/include/btree_ext.h: Likewise.
* db2/include/clib_ext.h: Likewise.
* db2/include/common_ext.h: Likewise.
* db2/include/hash_ext.h: Likewise.
* db2/include/lock_ext.h: Likewise.
* db2/include/log_ext.h: Likewise.
* db2/include/mp_ext.h: Likewise.
* db2/include/mutex_ext.h: Likewise.
* db2/include/os_ext.h: Likewise.
* db2/include/txn_ext.h: Likewise.
* db2/include/cxx_int.h: Likewise.
* db2/include/db_cxx.h: Likewise.
* db2/include/queue.h: Likewise.
* db2/lock/lock.c: Likewise.
* db2/lock/lock_conflict.c: Likewise.
* db2/lock/lock_util.c: Likewise.
* db2/lock/lock_deadlock.c: Likewise.
* db2/log/log.c: Likewise.
* db2/log/log_get.c: Likewise.
* db2/log/log.src: Likewise.
* db2/log/log_compare.c: Likewise.
* db2/log/log_put.c: Likewise.
* db2/log/log_rec.c: Likewise.
* db2/log/log_archive.c: Likewise.
* db2/log/log_register.c: Likewise.
* db2/log/log_auto.c: Likewise.
* db2/log/log_findckp.c: Likewise.
* db2/mp/mp_bh.c: Likewise.
* db2/mp/mp_fget.c: Likewise.
* db2/mp/mp_fopen.c: Likewise.
* db2/mp/mp_fput.c: Likewise.
* db2/mp/mp_fset.c: Likewise.
* db2/mp/mp_open.c: Likewise.
* db2/mp/mp_region.c: Likewise.
* db2/mp/mp_pr.c: Likewise.
* db2/mp/mp_sync.c: Likewise.
* db2/mutex/68020.gcc: Likewise.
* db2/mutex/mutex.c: Likewise.
* db2/mutex/README: Likewise.
* db2/mutex/x86.gcc: Likewise.
* db2/mutex/sparc.gcc: Likewise.
* db2/mutex/uts4.cc.s: Likewise.
* db2/mutex/alpha.dec: Likewise.
* db2/mutex/alpha.gcc: Likewise.
* db2/mutex/parisc.gcc: Likewise.
* db2/mutex/parisc.hp: Likewise.
* db2/os/db_os_abs.c: Likewise.
* db2/os/db_os_dir.c: Likewise.
* db2/os/db_os_fid.c: Likewise.
* db2/os/db_os_lseek.c: Likewise.
* db2/os/db_os_mmap.c: Likewise.
* db2/os/db_os_open.c: Likewise.
* db2/os/db_os_rw.c: Likewise.
* db2/os/db_os_sleep.c: Likewise.
* db2/os/db_os_stat.c: Likewise.
* db2/os/db_os_unlink.c: Likewise.
* db2/txn/txn.c: Likewise.
* db2/txn/txn.src: Likewise.
* db2/txn/txn_rec.c: Likewise.
* db2/txn/txn_auto.c: Likewise.
* db2/clib/getlong.c: Likewise.
* db2/progs/db_archive/db_archive.c: Likewise.
* db2/progs/db_checkpoint/db_checkpoint.c: Likewise.
* db2/progs/db_deadlock/db_deadlock.c: Likewise.
* db2/progs/db_dump/db_dump.c: Likewise.
* db2/progs/db_dump185/db_dump185.c: Likewise.
* db2/progs/db_load/db_load.c: Likewise.
* db2/progs/db_printlog/db_printlog.c: Likewise.
* db2/progs/db_recover/db_recover.c: Likewise.
* db2/progs/db_stat/db_stat.c: Likewise.
* libio/stdio.h [__cplusplus] (__STDIO_INLINE): Define as inline.
* po/de.po, po/sv.po: Update from 2.0.5 translations.
* sysdeps/unix/sysv/linux/netinet/tcp.h: Pretty print.
* sunrpc/rpc/xdr.h (XDR): Don't define argument of x_destroy callback
as const.
* sunrpc/xdr_mem.c (xdrmem_destroy): Don't define argument as const.
* sunrpx/xdr_rec.c (xdrrec_destroy): Likewise.
* sunrpx/xdr_stdio.c (xdrstdio_destroy): Likewise.
1997-08-27 18:47 Ulrich Drepper <drepper@cygnus.com>
* sysdeps/unix/sysv/linux/if_index.c: Include <errno.h>.
Reported by Benjamin Kosnik <bkoz@cygnus.com>.
1997-08-27 02:27 Roland McGrath <roland@baalperazim.frob.com>
* abi-tags: New file.
* csu/Makefile (distribute): Remove abi-tag.h.
($(objpfx)abi-tag.h): New target.
* Makefile (distribute): Add abi-tags.
* sysdeps/unix/sysv/linux/abi-tag.h: File removed.
* sysdeps/mach/hurd/abi-tag.h: File removed.
* sysdeps/stub/abi-tag.h: File removed.
1997-08-25 Andreas Schwab <schwab@issan.informatik.uni-dortmund.de>
* sysdeps/unix/make-syscalls.sh: Change output so that it
generates compilation rules only for the currently selected object
suffixes.
1997-08-25 Andreas Schwab <schwab@issan.informatik.uni-dortmund.de>
* sysdeps/m68k/dl-machine.h (RTLD_START): Switch back to previous
section to avoid confusing the compiler.
* sysdeps/alpha/dl-machine.h (RTLD_START): Likewise.
* sysdeps/i386/dl-machine.h (RTLD_START): Likewise.
* sysdeps/mips/dl-machine.h (RTLD_START): Likewise.
* sysdeps/mips/mips64/dl-machine.h (RTLD_START): Likewise.
* sysdeps/sparc/sparc32/dl-machine.h (RTLD_START): Likewise.
* sysdeps/m68k/dl-machine.h (elf_machine_load_address): Use a GOT
relocation instead of a constant to avoid text relocation.
(ELF_MACHINE_BEFORE_RTLD_RELOC): Removed.
(RTLD_START): Declare global labels as functions and add size
directive.
1997-08-25 17:01 Ulrich Drepper <drepper@cygnus.com>
* sysdeps/i386/bits/select.h: Correct assembler versions to work even
for descriptors >= 32.
* stdlib/alloca.h: Don't define alloca to __alloca since if gcc
is used __alloca is not defined to __builtin_alloca and so might
not be available.
Reported by Uwe Ohse <uwe@ohse.de>.
* sysdeps/unix/sysv/linux/sys/sysmacros.h: Define macros in a special
way if gcc is not used and so dev_t is an array.
Reported by Uwe Ohse <uwe@ohse.de>.
1997-08-23 Andreas Schwab <schwab@issan.informatik.uni-dortmund.de>
* manual/libc.texinfo: Reorder chapters to match logical order.
1997-08-25 12:22 Ulrich Drepper <drepper@cygnus.com>
* sunrpc/rpc/xdr.h: Change name of parameters in prototypes of
xdr_reference, xdrmem_create, and xdrstdio_create because of clash
with g++ internal symbols.
Patch by Sudish Joseph <sj@eng.mindspring.net>.
* elf/dl-deps.c: Implement handling of DT_FILTER.
Diffstat (limited to 'db2/include/db_page.h')
-rw-r--r-- | db2/include/db_page.h | 535 |
1 files changed, 535 insertions, 0 deletions
diff --git a/db2/include/db_page.h b/db2/include/db_page.h new file mode 100644 index 0000000000..9e78682c57 --- /dev/null +++ b/db2/include/db_page.h @@ -0,0 +1,535 @@ +/*- + * See the file LICENSE for redistribution information. + * + * Copyright (c) 1996, 1997 + * Sleepycat Software. All rights reserved. + * + * @(#)db_page.h 10.10 (Sleepycat) 8/18/97 + */ + +#ifndef _DB_PAGE_H_ +#define _DB_PAGE_H_ + +/* + * DB page formats. + * + * This implementation requires that values within the following structures + * NOT be padded -- note, ANSI C permits random padding within structures. + * If your compiler pads randomly you can just forget ever making DB run on + * your system. In addition, no data type can require larger alignment than + * its own size, e.g., a 4-byte data element may not require 8-byte alignment. + * + * Note that key/data lengths are often stored in db_indx_t's -- this is + * not accidental, nor does it limit the key/data size. If the key/data + * item fits on a page, it's guaranteed to be small enough to fit into a + * db_indx_t, and storing it in one saves space. + */ + +#define PGNO_METADATA 0 /* Metadata page number. */ +#define PGNO_INVALID 0 /* Metadata page number, therefore illegal. */ +#define PGNO_ROOT 1 /* Root is page #1. */ + +/************************************************************************ + BTREE METADATA PAGE LAYOUT + ************************************************************************/ + +/* + * Btree metadata page layout: + * + * +-----------------------------------+ + * | lsn | pgno | magic | + * +-----------------------------------+ + * | version | pagesize | free | + * +-----------------------------------+ + * | flags | unused ... | + * +-----------------------------------+ + */ +typedef struct _btmeta { + DB_LSN lsn; /* 00-07: LSN. */ + db_pgno_t pgno; /* 08-11: Current page number. */ + u_int32_t magic; /* 12-15: Magic number. */ + u_int32_t version; /* 16-19: Version. */ + u_int32_t pagesize; /* 20-23: Pagesize. */ + u_int32_t maxkey; /* 24-27: Btree: Maxkey. */ + u_int32_t minkey; /* 28-31: Btree: Minkey. */ + u_int32_t free; /* 32-35: Free list page number. */ +#define BTM_DUP 0x001 /* Duplicates. */ +#define BTM_RECNO 0x002 /* Recno tree. */ +#define BTM_RECNUM 0x004 /* Btree: maintain record count. */ +#define BTM_FIXEDLEN 0x008 /* Recno: fixed length records. */ +#define BTM_RENUMBER 0x010 /* Recno: renumber on insert/delete. */ +#define BTM_MASK 0x01f + u_int32_t flags; /* 36-39: Flags. */ + u_int32_t re_len; /* 40-43: Recno: fixed-length record length. */ + u_int32_t re_pad; /* 44-47: Recno: fixed-length record pad. */ + /* 48-67: Unique file ID. */ + u_int8_t uid[DB_FILE_ID_LEN]; + + u_int32_t spare[13]; /* 68-123: Save some room for growth. */ + + DB_BTREE_LSTAT stat; /* 124-163: Statistics. */ +} BTMETA; + +/************************************************************************ + HASH METADATA PAGE LAYOUT + ************************************************************************/ + +/* + * Hash metadata page layout: + * + * +-----------------------------------+ + * | lsn | magic | version | + * +-----------------------------------+ + * | pagesize | ovfl_point| last_freed| + * +-----------------------------------+ + * | max_bucket| high_mask | low_mask | + * +-----------------------------------+ + * | ffactor | nelem | charkey | + * +-----------------------------------+ + * | spares[32]| flags | unused | + * +-----------------------------------+ + */ +/* Hash Table Information */ +typedef struct hashhdr { /* Disk resident portion */ + DB_LSN lsn; /* 00-07: LSN of the header page */ + db_pgno_t pgno; /* 08-11: Page number (btree compatibility). */ + u_int32_t magic; /* 12-15: Magic NO for hash tables */ + u_int32_t version; /* 16-19: Version ID */ + u_int32_t pagesize; /* 20-23: Bucket/Page Size */ + u_int32_t ovfl_point; /* 24-27: Overflow page allocation location */ + u_int32_t last_freed; /* 28-31: Last freed overflow page pgno */ + u_int32_t max_bucket; /* 32-35: ID of Maximum bucket in use */ + u_int32_t high_mask; /* 36-39: Modulo mask into table */ + u_int32_t low_mask; /* 40-43: Modulo mask into table lower half */ + u_int32_t ffactor; /* 44-47: Fill factor */ + u_int32_t nelem; /* 48-51: Number of keys in hash table */ + u_int32_t h_charkey; /* 52-55: Value of hash(CHARKEY) */ +#define DB_HASH_DUP 0x01 + u_int32_t flags; /* 56-59: Allow duplicates. */ +#define NCACHED 32 /* number of spare points */ + /* 60-187: Spare pages for overflow */ + u_int32_t spares[NCACHED]; + /* 188-207: Unique file ID. */ + u_int8_t uid[DB_FILE_ID_LEN]; + + /* + * Minimum page size is 256. + */ +} HASHHDR; + +/************************************************************************ + MAIN PAGE LAYOUT + ************************************************************************/ + +/* + * +-----------------------------------+ + * | lsn | pgno | prev pgno | + * +-----------------------------------+ + * | next pgno | entries | hf offset | + * +-----------------------------------+ + * | level | type | index | + * +-----------------------------------+ + * | index | free --> | + * +-----------+-----------------------+ + * | F R E E A R E A | + * +-----------------------------------+ + * | <-- free | item | + * +-----------------------------------+ + * | item | item | item | + * +-----------------------------------+ + * + * sizeof(PAGE) == 26 bytes, and the following indices are guaranteed to be + * two-byte aligned. + * + * For hash and btree leaf pages, index items are paired, e.g., inp[0] is the + * key for inp[1]'s data. All other types of pages only contain single items. + */ +typedef struct _db_page { + DB_LSN lsn; /* 00-07: Log sequence number. */ + db_pgno_t pgno; /* 08-11: Current page number. */ + db_pgno_t prev_pgno; /* 12-15: Previous page number. */ + db_pgno_t next_pgno; /* 16-19: Next page number. */ + db_indx_t entries; /* 20-21: Number of item pairs on the page. */ + db_indx_t hf_offset; /* 22-23: High free byte page offset. */ + + /* + * The btree levels are numbered from the leaf to the root, starting + * with 1, so the leaf is level 1, its parent is level 2, and so on. + * We maintain this level on all btree pages, but the only place that + * we actually need it is on the root page. It would not be difficult + * to hide the byte on the root page once it becomes an internal page, + * so we could get this byte back if we needed it for something else. + */ +#define LEAFLEVEL 1 +#define MAXBTREELEVEL 255 + u_int8_t level; /* 24: Btree tree level. */ + +#define P_INVALID 0 /* Invalid page type. */ +#define P_DUPLICATE 1 /* Duplicate. */ +#define P_HASH 2 /* Hash. */ +#define P_IBTREE 3 /* Btree internal. */ +#define P_IRECNO 4 /* Recno internal. */ +#define P_LBTREE 5 /* Btree leaf. */ +#define P_LRECNO 6 /* Recno leaf. */ +#define P_OVERFLOW 7 /* Overflow. */ + u_int8_t type; /* 25: Page type. */ + db_indx_t inp[1]; /* Variable length index of items. */ +} PAGE; + +/* Element macros. */ +#define LSN(p) (((PAGE *)p)->lsn) +#define PGNO(p) (((PAGE *)p)->pgno) +#define PREV_PGNO(p) (((PAGE *)p)->prev_pgno) +#define NEXT_PGNO(p) (((PAGE *)p)->next_pgno) +#define NUM_ENT(p) (((PAGE *)p)->entries) +#define HOFFSET(p) (((PAGE *)p)->hf_offset) +#define LEVEL(p) (((PAGE *)p)->level) +#define TYPE(p) (((PAGE *)p)->type) + +/* + * !!! + * The next_pgno and prev_pgno fields are not maintained for btree and recno + * internal pages. It's a minor performance improvement, and more, it's + * hard to do when deleting internal pages, and it decreases the chance of + * deadlock during deletes and splits. + * + * !!! + * The btree/recno access method needs db_recno_t bytes of space on the root + * page to specify how many records are stored in the tree. (The alternative + * is to store the number of records in the meta-data page, which will create + * a second hot spot in trees being actively modified, or recalculate it from + * the BINTERNAL fields on each access.) Overload the prev_pgno field. + */ +#define RE_NREC(p) \ + (TYPE(p) == P_LBTREE ? NUM_ENT(p) / 2 : \ + TYPE(p) == P_LRECNO ? NUM_ENT(p) : PREV_PGNO(p)) +#define RE_NREC_ADJ(p, adj) \ + PREV_PGNO(p) += adj; +#define RE_NREC_SET(p, num) \ + PREV_PGNO(p) = num; + +/* + * Initialize a page. + * + * !!! + * Don't modify the page's LSN, code depends on it being unchanged after a + * P_INIT call. + */ +#define P_INIT(pg, pg_size, n, pg_prev, pg_next, btl, pg_type) do { \ + PGNO(pg) = n; \ + PREV_PGNO(pg) = pg_prev; \ + NEXT_PGNO(pg) = pg_next; \ + NUM_ENT(pg) = 0; \ + HOFFSET(pg) = pg_size; \ + LEVEL(pg) = btl; \ + TYPE(pg) = pg_type; \ +} while (0) + +/* Page header length (offset to first index). */ +#define P_OVERHEAD (SSZA(PAGE, inp)) + +/* First free byte. */ +#define LOFFSET(pg) (P_OVERHEAD + NUM_ENT(pg) * sizeof(db_indx_t)) + +/* Free space on the page. */ +#define P_FREESPACE(pg) (HOFFSET(pg) - LOFFSET(pg)) + +/* Get a pointer to the bytes at a specific index. */ +#define P_ENTRY(pg, indx) ((u_int8_t *)pg + ((PAGE *)pg)->inp[indx]) + +/************************************************************************ + OVERFLOW PAGE LAYOUT + ************************************************************************/ + +/* + * Overflow items are referenced by HOFFPAGE and BOVERFLOW structures, which + * store a page number (the first page of the overflow item) and a length + * (the total length of the overflow item). The overflow item consists of + * some number of overflow pages, linked by the next_pgno field of the page. + * A next_pgno field of PGNO_INVALID flags the end of the overflow item. + * + * Overflow page overloads: + * The amount of overflow data stored on each page is stored in the + * hf_offset field. + * + * The implementation reference counts overflow items as it's possible + * for them to be promoted onto btree internal pages. The reference + * count is stored in the entries field. + */ +#define OV_LEN(p) (((PAGE *)p)->hf_offset) +#define OV_REF(p) (((PAGE *)p)->entries) + +/* Maximum number of bytes that you can put on an overflow page. */ +#define P_MAXSPACE(psize) ((psize) - P_OVERHEAD) + +/************************************************************************ + HASH PAGE LAYOUT + ************************************************************************/ + +/* Each index references a group of bytes on the page. */ +#define H_KEYDATA 1 /* Key/data item. */ +#define H_DUPLICATE 2 /* Duplicate key/data item. */ +#define H_OFFPAGE 3 /* Overflow key/data item. */ +#define H_OFFDUP 4 /* Overflow page of duplicates. */ + +/* + * The first and second types are H_KEYDATA and H_DUPLICATE, represented + * by the HKEYDATA structure: + * + * +-----------------------------------+ + * | type | key/data ... | + * +-----------------------------------+ + * + * For duplicates, the data field encodes duplicate elements in the data + * field: + * + * +---------------------------------------------------------------+ + * | type | len1 | element1 | len1 | len2 | element2 | len2 | + * +---------------------------------------------------------------+ + * + * Thus, by keeping track of the offset in the element, we can do both + * backward and forward traversal. + */ +typedef struct _hkeydata { + u_int8_t type; /* 00: Page type. */ + u_int8_t data[1]; /* Variable length key/data item. */ +} HKEYDATA; + +/* Get a HKEYDATA item for a specific index. */ +#define GET_HKEYDATA(pg, indx) \ + ((HKEYDATA *)P_ENTRY(pg, indx)) + +/* + * The length of any HKEYDATA item. Note that indx is an element index, + * not a PAIR index. + */ +#define LEN_HITEM(pg, pgsize, indx) \ + (((indx) == 0 ? pgsize : pg->inp[indx - 1]) - pg->inp[indx]) + +#define LEN_HKEYDATA(pg, psize, indx) \ + (((indx) == 0 ? psize : pg->inp[indx - 1]) - \ + pg->inp[indx] - HKEYDATA_SIZE(0)) + +/* + * Page space required to add a new HKEYDATA item to the page, with and + * without the index value. + */ +#define HKEYDATA_SIZE(len) \ + ((len) + SSZA(HKEYDATA, data)) +#define HKEYDATA_PSIZE(len) \ + (HKEYDATA_SIZE(len) + sizeof(db_indx_t)) + +/* Put a HKEYDATA item at the location referenced by a page entry. */ +#define PUT_HKEYDATA(pe, kd, len, type) { \ + ((HKEYDATA *)pe)->type = type; \ + memcpy((u_int8_t *)pe + sizeof(u_int8_t), kd, len); \ +} + +/* + * Macros the describe the page layout in terms of key-data pairs. + * The use of "pindex" indicates that the argument is the index + * expressed in pairs instead of individual elements. + */ +#define H_NUMPAIRS(pg) (NUM_ENT(pg) / 2) +#define H_KEYINDEX(pindx) (2 * (pindx)) +#define H_DATAINDEX(pindx) ((2 * (pindx)) + 1) +#define H_PAIRKEY(pg, pindx) GET_HKEYDATA(pg, H_KEYINDEX(pindx)) +#define H_PAIRDATA(pg, pindx) GET_HKEYDATA(pg, H_DATAINDEX(pindx)) +#define H_PAIRSIZE(pg, psize, pindx) \ + (LEN_HITEM(pg, psize, H_KEYINDEX(pindx)) + \ + LEN_HITEM(pg, psize, H_DATAINDEX(pindx))) +#define LEN_HDATA(p, psize, pindx) LEN_HKEYDATA(p, psize, H_DATAINDEX(pindx)) +#define LEN_HKEY(p, psize, pindx) LEN_HKEYDATA(p, psize, H_KEYINDEX(pindx)) + +/* + * The third type is the H_OFFPAGE, represented by the HOFFPAGE structure: + * + * +-----------------------------------+ + * | type | pgno_t | total len | + * +-----------------------------------+ + */ +typedef struct _hoffpage { + u_int8_t type; /* 00: Page type and delete flag. */ + u_int8_t unused[3]; /* 01-03: Padding, unused. */ + db_pgno_t pgno; /* 04-07: Offpage page number. */ + u_int32_t tlen; /* 08-11: Total length of item. */ +} HOFFPAGE; + +/* Get a HOFFPAGE item for a specific index. */ +#define GET_HOFFPAGE(pg, indx) \ + ((HOFFPAGE *)P_ENTRY(pg, indx)) + +/* + * Page space required to add a new HOFFPAGE item to the page, with and + * without the index value. + */ +#define HOFFPAGE_SIZE (sizeof(HOFFPAGE)) +#define HOFFPAGE_PSIZE (HOFFPAGE_SIZE + sizeof(db_indx_t)) + +/* + * The fourth type is H_OFFDUP represented by the HOFFDUP structure: + * + * +-----------------------+ + * | type | pgno_t | + * +-----------------------+ + */ +typedef struct _hoffdup { + u_int8_t type; /* 00: Page type and delete flag. */ + u_int8_t unused[3]; /* 01-03: Padding, unused. */ + db_pgno_t pgno; /* 04-07: Offpage page number. */ +} HOFFDUP; + +/* Get a HOFFDUP item for a specific index. */ +#define GET_HOFFDUP(pg, indx) \ + ((HOFFDUP *)P_ENTRY(pg, indx)) + +/* + * Page space required to add a new HOFFDUP item to the page, with and + * without the index value. + */ +#define HOFFDUP_SIZE (sizeof(HOFFDUP)) +#define HOFFDUP_PSIZE (HOFFDUP_SIZE + sizeof(db_indx_t)) + +/************************************************************************ + BTREE PAGE LAYOUT + ************************************************************************/ + +/* Each index references a group of bytes on the page. */ +#define B_KEYDATA 1 /* Key/data item. */ +#define B_DUPLICATE 2 /* Duplicate key/data item. */ +#define B_OVERFLOW 3 /* Overflow key/data item. */ + +/* + * The first type is B_KEYDATA, represented by the BKEYDATA structure: + * + * +-----------------------------------+ + * | length | type | key/data | + * +-----------------------------------+ + */ +typedef struct _bkeydata { + db_indx_t len; /* 00-01: Key/data item length. */ + u_int deleted :1; /* 02: Page type and delete flag. */ + u_int type :7; + u_int8_t data[1]; /* Variable length key/data item. */ +} BKEYDATA; + +/* Get a BKEYDATA item for a specific index. */ +#define GET_BKEYDATA(pg, indx) \ + ((BKEYDATA *)P_ENTRY(pg, indx)) + +/* + * Page space required to add a new BKEYDATA item to the page, with and + * without the index value. + */ +#define BKEYDATA_SIZE(len) \ + ALIGN((len) + SSZA(BKEYDATA, data), 4) +#define BKEYDATA_PSIZE(len) \ + (BKEYDATA_SIZE(len) + sizeof(db_indx_t)) + +/* + * The second and third types are B_DUPLICATE and B_OVERFLOW, represented + * by the BOVERFLOW structure: + * + * +-----------------------------------+ + * | total len | type | unused | + * +-----------------------------------+ + * | nxt: page | nxt: off | nxt: len | + * +-----------------------------------+ + */ +typedef struct _boverflow { + db_indx_t unused1; /* 00-01: Padding, unused. */ + u_int deleted :1; /* 02: Page type and delete flag. */ + u_int type :7; + u_int8_t unused2; /* 03: Padding, unused. */ + db_pgno_t pgno; /* 04-07: Next page number. */ + u_int32_t tlen; /* 08-11: Total length of item. */ +} BOVERFLOW; + +/* Get a BOVERFLOW item for a specific index. */ +#define GET_BOVERFLOW(pg, indx) \ + ((BOVERFLOW *)P_ENTRY(pg, indx)) + +/* + * Page space required to add a new BOVERFLOW item to the page, with and + * without the index value. + */ +#define BOVERFLOW_SIZE \ + ALIGN(sizeof(BOVERFLOW), 4) +#define BOVERFLOW_PSIZE \ + (BOVERFLOW_SIZE + sizeof(db_indx_t)) + +/* + * Btree leaf and hash page layouts group indices in sets of two, one + * for the key and one for the data. Everything else does it in sets + * of one to save space. I use the following macros so that it's real + * obvious what's going on... + */ +#define O_INDX 1 +#define P_INDX 2 + +/************************************************************************ + BTREE INTERNAL PAGE LAYOUT + ************************************************************************/ + +/* + * Btree internal entry. + * + * +-----------------------------------+ + * | leaf pgno | type | data ... | + * +-----------------------------------+ + */ +typedef struct _binternal { + db_indx_t len; /* 00-01: Key/data item length. */ + u_int deleted :1; /* 02: Page type and delete flag. */ + u_int type :7; + u_int8_t unused; /* 03: Padding, unused. */ + db_pgno_t pgno; /* 04-07: Page number of referenced page. */ + db_recno_t nrecs; /* 08-11: Subtree record count. */ + u_int8_t data[1]; /* Variable length key item. */ +} BINTERNAL; + +/* Get a BINTERNAL item for a specific index. */ +#define GET_BINTERNAL(pg, indx) \ + ((BINTERNAL *)P_ENTRY(pg, indx)) + +/* + * Page space required to add a new BINTERNAL item to the page, with and + * without the index value. + */ +#define BINTERNAL_SIZE(len) \ + ALIGN((len) + SSZA(BINTERNAL, data), 4) +#define BINTERNAL_PSIZE(len) \ + (BINTERNAL_SIZE(len) + sizeof(db_indx_t)) + +/************************************************************************ + RECNO INTERNAL PAGE LAYOUT + ************************************************************************/ + +/* + * The recno internal entry. + * + * +-----------------------+ + * | leaf pgno | # of recs | + * +-----------------------+ + * + * XXX + * Why not fold this into the db_indx_t structure, it's fixed length. + */ +typedef struct _rinternal { + db_pgno_t pgno; /* 00-03: Page number of referenced page. */ + db_recno_t nrecs; /* 04-07: Subtree record count. */ +} RINTERNAL; + +/* Get a RINTERNAL item for a specific index. */ +#define GET_RINTERNAL(pg, indx) \ + ((RINTERNAL *)P_ENTRY(pg, indx)) + +/* + * Page space required to add a new RINTERNAL item to the page, with and + * without the index value. + */ +#define RINTERNAL_SIZE \ + ALIGN(sizeof(RINTERNAL), 4) +#define RINTERNAL_PSIZE \ + (RINTERNAL_SIZE + sizeof(db_indx_t)) +#endif /* _DB_PAGE_H_ */ |