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authorUlrich Drepper <drepper@redhat.com>1997-08-27 20:26:10 +0000
committerUlrich Drepper <drepper@redhat.com>1997-08-27 20:26:10 +0000
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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.h535
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
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--- /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_ */