/*- * See the file LICENSE for redistribution information. * * Copyright (c) 1996,2007 Oracle. All rights reserved. * * $Id: db_page.h,v 12.13 2007/05/17 15:15:05 bostic Exp $ */ #ifndef _DB_PAGE_H_ #define _DB_PAGE_H_ #if defined(__cplusplus) extern "C" { #endif /* * 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_INVALID 0 /* Invalid page number in any database. */ #define PGNO_BASE_MD 0 /* Base database: metadata page number. */ /* Page types. */ #define P_INVALID 0 /* Invalid page type. */ #define __P_DUPLICATE 1 /* Duplicate. DEPRECATED in 3.1 */ #define P_HASH_UNSORTED 2 /* Hash pages created pre 4.6. DEPRECATED */ #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. */ #define P_HASHMETA 8 /* Hash metadata page. */ #define P_BTREEMETA 9 /* Btree metadata page. */ #define P_QAMMETA 10 /* Queue metadata page. */ #define P_QAMDATA 11 /* Queue data page. */ #define P_LDUP 12 /* Off-page duplicate leaf. */ #define P_HASH 13 /* Sorted hash page. */ #define P_PAGETYPE_MAX 14 /* Flag to __db_new */ #define P_DONTEXTEND 0x8000 /* Don't allocate if there are no free pages. */ /* * When we create pages in mpool, we ask mpool to clear some number of bytes * in the header. This number must be at least as big as the regular page * headers and cover enough of the btree and hash meta-data pages to obliterate * the page type. */ #define DB_PAGE_DB_LEN 32 #define DB_PAGE_QUEUE_LEN 0 /************************************************************************ GENERIC METADATA PAGE HEADER * * !!! * The magic and version numbers have to be in the same place in all versions * of the metadata page as the application may not have upgraded the database. ************************************************************************/ typedef struct _dbmeta33 { 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_int8_t encrypt_alg; /* 24: Encryption algorithm. */ u_int8_t type; /* 25: Page type. */ #define DBMETA_CHKSUM 0x01 u_int8_t metaflags; /* 26: Meta-only flags */ u_int8_t unused1; /* 27: Unused. */ u_int32_t free; /* 28-31: Free list page number. */ db_pgno_t last_pgno; /* 32-35: Page number of last page in db. */ u_int32_t unused3; /* 36-39: Unused. */ u_int32_t key_count; /* 40-43: Cached key count. */ u_int32_t record_count; /* 44-47: Cached record count. */ u_int32_t flags; /* 48-51: Flags: unique to each AM. */ /* 52-71: Unique file ID. */ u_int8_t uid[DB_FILE_ID_LEN]; } DBMETA33, DBMETA; /************************************************************************ BTREE METADATA PAGE LAYOUT ************************************************************************/ typedef struct _btmeta33 { #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_SUBDB 0x020 /* Subdatabases. */ #define BTM_DUPSORT 0x040 /* Duplicates are sorted. */ #define BTM_MASK 0x07f DBMETA dbmeta; /* 00-71: Generic meta-data header. */ u_int32_t unused1; /* 72-75: Unused space. */ u_int32_t minkey; /* 76-79: Btree: Minkey. */ u_int32_t re_len; /* 80-83: Recno: fixed-length record length. */ u_int32_t re_pad; /* 84-87: Recno: fixed-length record pad. */ u_int32_t root; /* 88-91: Root page. */ u_int32_t unused2[92]; /* 92-459: Unused space. */ u_int32_t crypto_magic; /* 460-463: Crypto magic number */ u_int32_t trash[3]; /* 464-475: Trash space - Do not use */ u_int8_t iv[DB_IV_BYTES]; /* 476-495: Crypto IV */ u_int8_t chksum[DB_MAC_KEY]; /* 496-511: Page chksum */ /* * Minimum page size is 512. */ } BTMETA33, BTMETA; /************************************************************************ HASH METADATA PAGE LAYOUT ************************************************************************/ typedef struct _hashmeta33 { #define DB_HASH_DUP 0x01 /* Duplicates. */ #define DB_HASH_SUBDB 0x02 /* Subdatabases. */ #define DB_HASH_DUPSORT 0x04 /* Duplicates are sorted. */ DBMETA dbmeta; /* 00-71: Generic meta-data page header. */ u_int32_t max_bucket; /* 72-75: ID of Maximum bucket in use */ u_int32_t high_mask; /* 76-79: Modulo mask into table */ u_int32_t low_mask; /* 80-83: Modulo mask into table lower half */ u_int32_t ffactor; /* 84-87: Fill factor */ u_int32_t nelem; /* 88-91: Number of keys in hash table */ u_int32_t h_charkey; /* 92-95: Value of hash(CHARKEY) */ #define NCACHED 32 /* number of spare points */ /* 96-223: Spare pages for overflow */ u_int32_t spares[NCACHED]; u_int32_t unused[59]; /* 224-459: Unused space */ u_int32_t crypto_magic; /* 460-463: Crypto magic number */ u_int32_t trash[3]; /* 464-475: Trash space - Do not use */ u_int8_t iv[DB_IV_BYTES]; /* 476-495: Crypto IV */ u_int8_t chksum[DB_MAC_KEY]; /* 496-511: Page chksum */ /* * Minimum page size is 512. */ } HMETA33, HMETA; /************************************************************************ QUEUE METADATA PAGE LAYOUT ************************************************************************/ /* * QAM Meta data page structure * */ typedef struct _qmeta33 { DBMETA dbmeta; /* 00-71: Generic meta-data header. */ u_int32_t first_recno; /* 72-75: First not deleted record. */ u_int32_t cur_recno; /* 76-79: Next recno to be allocated. */ u_int32_t re_len; /* 80-83: Fixed-length record length. */ u_int32_t re_pad; /* 84-87: Fixed-length record pad. */ u_int32_t rec_page; /* 88-91: Records Per Page. */ u_int32_t page_ext; /* 92-95: Pages per extent */ u_int32_t unused[91]; /* 96-459: Unused space */ u_int32_t crypto_magic; /* 460-463: Crypto magic number */ u_int32_t trash[3]; /* 464-475: Trash space - Do not use */ u_int8_t iv[DB_IV_BYTES]; /* 476-495: Crypto IV */ u_int8_t chksum[DB_MAC_KEY]; /* 496-511: Page chksum */ /* * Minimum page size is 512. */ } QMETA33, QMETA; /* * DBMETASIZE is a constant used by __db_file_setup and DB->verify * as a buffer which is guaranteed to be larger than any possible * metadata page size and smaller than any disk sector. */ #define DBMETASIZE 512 /************************************************************************ BTREE/HASH MAIN PAGE LAYOUT ************************************************************************/ /* * +-----------------------------------+ * | lsn | pgno | prev pgno | * +-----------------------------------+ * | next pgno | entries | hf offset | * +-----------------------------------+ * | level | type | chksum | * +-----------------------------------+ * | iv | index | free --> | * +-----------+-----------------------+ * | F R E E A R E A | * +-----------------------------------+ * | <-- free | item | * +-----------------------------------+ * | item | item | item | * +-----------------------------------+ * * sizeof(PAGE) == 26 bytes + possibly 20 bytes of checksum and possibly * 16 bytes of IV (+ 2 bytes for alignment), and the following indices * are guaranteed to be two-byte aligned. If we aren't doing crypto or * checksumming the bytes are reclaimed for data storage. * * 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 __pg_chksum { u_int8_t unused[2]; /* 26-27: For alignment */ u_int8_t chksum[4]; /* 28-31: Checksum */ } PG_CHKSUM; typedef struct __pg_crypto { u_int8_t unused[2]; /* 26-27: For alignment */ u_int8_t chksum[DB_MAC_KEY]; /* 28-47: Checksum */ u_int8_t iv[DB_IV_BYTES]; /* 48-63: IV */ /* !!! * Must be 16-byte aligned for crypto */ } PG_CRYPTO; 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 items 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. */ u_int8_t type; /* 25: Page type. */ } PAGE; /* * With many compilers sizeof(PAGE) == 28, while SIZEOF_PAGE == 26. * We add in other things directly after the page header and need * the SIZEOF_PAGE. When giving the sizeof(), many compilers will * pad it out to the next 4-byte boundary. */ #define SIZEOF_PAGE 26 /* * !!! * DB_AM_ENCRYPT always implies DB_AM_CHKSUM so that must come first. */ #define P_INP(dbp, pg) \ ((db_indx_t *)((u_int8_t *)(pg) + SIZEOF_PAGE + \ (F_ISSET((dbp), DB_AM_ENCRYPT) ? sizeof(PG_CRYPTO) : \ (F_ISSET((dbp), DB_AM_CHKSUM) ? sizeof(PG_CHKSUM) : 0)))) #define P_IV(dbp, pg) \ (F_ISSET((dbp), DB_AM_ENCRYPT) ? ((u_int8_t *)(pg) + \ SIZEOF_PAGE + SSZA(PG_CRYPTO, iv)) \ : NULL) #define P_CHKSUM(dbp, pg) \ (F_ISSET((dbp), DB_AM_ENCRYPT) ? ((u_int8_t *)(pg) + \ SIZEOF_PAGE + SSZA(PG_CRYPTO, chksum)) : \ (F_ISSET((dbp), DB_AM_CHKSUM) ? ((u_int8_t *)(pg) + \ SIZEOF_PAGE + SSZA(PG_CHKSUM, chksum)) \ : NULL)) /* 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) /************************************************************************ QUEUE MAIN PAGE LAYOUT ************************************************************************/ /* * Sizes of page below. Used to reclaim space if not doing * crypto or checksumming. If you change the QPAGE below you * MUST adjust this too. */ #define QPAGE_NORMAL 28 #define QPAGE_CHKSUM 48 #define QPAGE_SEC 64 typedef struct _qpage { DB_LSN lsn; /* 00-07: Log sequence number. */ db_pgno_t pgno; /* 08-11: Current page number. */ u_int32_t unused0[3]; /* 12-23: Unused. */ u_int8_t unused1[1]; /* 24: Unused. */ u_int8_t type; /* 25: Page type. */ u_int8_t unused2[2]; /* 26-27: Unused. */ u_int8_t chksum[DB_MAC_KEY]; /* 28-47: Checksum */ u_int8_t iv[DB_IV_BYTES]; /* 48-63: IV */ } QPAGE; #define QPAGE_SZ(dbp) \ (F_ISSET((dbp), DB_AM_ENCRYPT) ? QPAGE_SEC : \ F_ISSET((dbp), DB_AM_CHKSUM) ? QPAGE_CHKSUM : QPAGE_NORMAL) /* * !!! * The next_pgno and prev_pgno fields are not maintained for btree and recno * internal pages. Doing so only provides a minor performance improvement, * it's hard to do when deleting internal pages, and it increases the chance * of deadlock during deletes and splits because we have to re-link pages at * more than the leaf level. * * !!! * 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_IBTREE || TYPE(p) == P_IRECNO) ? PREV_PGNO(p) : \ (db_pgno_t)(TYPE(p) == P_LBTREE ? NUM_ENT(p) / 2 : NUM_ENT(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) = (db_indx_t)(pg_size); \ LEVEL(pg) = (btl); \ TYPE(pg) = (pg_type); \ } while (0) /* Page header length (offset to first index). */ #define P_OVERHEAD(dbp) P_TO_UINT16(P_INP(dbp, 0)) /* First free byte. */ #define LOFFSET(dbp, pg) \ (P_OVERHEAD(dbp) + NUM_ENT(pg) * sizeof(db_indx_t)) /* Free space on a regular page. */ #define P_FREESPACE(dbp, pg) (HOFFSET(pg) - LOFFSET(dbp, pg)) /* Get a pointer to the bytes at a specific index. */ #define P_ENTRY(dbp, pg, indx) ((u_int8_t *)pg + P_INP(dbp, pg)[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(dbp, psize) ((psize) - P_OVERHEAD(dbp)) /* Free space on an overflow page. */ #define P_OVFLSPACE(dbp, psize, pg) (P_MAXSPACE(dbp, psize) - HOFFSET(pg)) /************************************************************************ 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. */ /* * !!! * Items on hash pages are (potentially) unaligned, so we can never cast the * (page + offset) pointer to an HKEYDATA, HOFFPAGE or HOFFDUP structure, as * we do with B+tree on-page structures. Because we frequently want the type * field, it requires no alignment, and it's in the same location in all three * structures, there's a pair of macros. */ #define HPAGE_PTYPE(p) (*(u_int8_t *)p) #define HPAGE_TYPE(dbp, pg, indx) (*P_ENTRY(dbp, pg, indx)) /* * 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; #define HKEYDATA_DATA(p) (((u_int8_t *)p) + SSZA(HKEYDATA, data)) /* * The length of any HKEYDATA item. Note that indx is an element index, * not a PAIR index. */ #define LEN_HITEM(dbp, pg, pgsize, indx) \ (((indx) == 0 ? (pgsize) : \ (P_INP(dbp, pg)[(indx) - 1])) - (P_INP(dbp, pg)[indx])) #define LEN_HKEYDATA(dbp, pg, psize, indx) \ (db_indx_t)(LEN_HITEM(dbp, pg, psize, 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, etype) { \ ((HKEYDATA *)(pe))->type = etype; \ memcpy((u_int8_t *)(pe) + sizeof(u_int8_t), kd, len); \ } /* * Macros the describe the page layout in terms of key-data pairs. */ #define H_NUMPAIRS(pg) (NUM_ENT(pg) / 2) #define H_KEYINDEX(indx) (indx) #define H_DATAINDEX(indx) ((indx) + 1) #define H_PAIRKEY(dbp, pg, indx) P_ENTRY(dbp, pg, H_KEYINDEX(indx)) #define H_PAIRDATA(dbp, pg, indx) P_ENTRY(dbp, pg, H_DATAINDEX(indx)) #define H_PAIRSIZE(dbp, pg, psize, indx) \ (LEN_HITEM(dbp, pg, psize, H_KEYINDEX(indx)) + \ LEN_HITEM(dbp, pg, psize, H_DATAINDEX(indx))) #define LEN_HDATA(dbp, p, psize, indx) \ LEN_HKEYDATA(dbp, p, psize, H_DATAINDEX(indx)) #define LEN_HKEY(dbp, p, psize, indx) \ LEN_HKEYDATA(dbp, p, psize, H_KEYINDEX(indx)) /* * The third type is the H_OFFPAGE, represented by the HOFFPAGE structure: */ 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; #define HOFFPAGE_PGNO(p) (((u_int8_t *)p) + SSZ(HOFFPAGE, pgno)) #define HOFFPAGE_TLEN(p) (((u_int8_t *)p) + SSZ(HOFFPAGE, tlen)) /* * 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: */ 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; #define HOFFDUP_PGNO(p) (((u_int8_t *)p) + SSZ(HOFFDUP, pgno)) /* * Page space required to add a new HOFFDUP item to the page, with and * without the index value. */ #define HOFFDUP_SIZE (sizeof(HOFFDUP)) /************************************************************************ 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. */ /* * We have to store a deleted entry flag in the page. The reason is complex, * but the simple version is that we can't delete on-page items referenced by * a cursor -- the return order of subsequent insertions might be wrong. The * delete flag is an overload of the top bit of the type byte. */ #define B_DELETE (0x80) #define B_DCLR(t) (t) &= ~B_DELETE #define B_DSET(t) (t) |= B_DELETE #define B_DISSET(t) ((t) & B_DELETE) #define B_TYPE(t) ((t) & ~B_DELETE) #define B_TSET(t, type) ((t) = B_TYPE(type)) #define B_TSET_DELETED(t, type) ((t) = (type) | B_DELETE) /* * The first type is B_KEYDATA, represented by the BKEYDATA structure: */ typedef struct _bkeydata { db_indx_t len; /* 00-01: Key/data item length. */ u_int8_t type; /* 02: Page type AND DELETE FLAG. */ u_int8_t data[1]; /* Variable length key/data item. */ } BKEYDATA; /* Get a BKEYDATA item for a specific index. */ #define GET_BKEYDATA(dbp, pg, indx) \ ((BKEYDATA *)P_ENTRY(dbp, pg, indx)) /* * Page space required to add a new BKEYDATA item to the page, with and * without the index value. The (u_int16_t) cast avoids warnings: DB_ALIGN * casts to uintmax_t, the cast converts it to a small integral type so we * don't get complaints when we assign the final result to an integral type * smaller than uintmax_t. */ #define BKEYDATA_SIZE(len) \ (u_int16_t)DB_ALIGN((len) + SSZA(BKEYDATA, data), sizeof(u_int32_t)) #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. */ typedef struct _boverflow { db_indx_t unused1; /* 00-01: Padding, unused. */ u_int8_t type; /* 02: Page type AND DELETE FLAG. */ 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(dbp, pg, indx) \ ((BOVERFLOW *)P_ENTRY(dbp, pg, indx)) /* * Page space required to add a new BOVERFLOW item to the page, with and * without the index value. */ #define BOVERFLOW_SIZE \ ((u_int16_t)DB_ALIGN(sizeof(BOVERFLOW), sizeof(u_int32_t))) #define BOVERFLOW_PSIZE \ (BOVERFLOW_SIZE + sizeof(db_indx_t)) #define BITEM_SIZE(bk) \ (B_TYPE((bk)->type) != B_KEYDATA ? BOVERFLOW_SIZE : \ BKEYDATA_SIZE((bk)->len)) #define BITEM_PSIZE(bk) \ (B_TYPE((bk)->type) != B_KEYDATA ? BOVERFLOW_PSIZE : \ BKEYDATA_PSIZE((bk)->len)) /* * 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. 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. */ typedef struct _binternal { db_indx_t len; /* 00-01: Key/data item length. */ u_int8_t type; /* 02: Page type AND DELETE FLAG. */ 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(dbp, pg, indx) \ ((BINTERNAL *)P_ENTRY(dbp, pg, indx)) /* * Page space required to add a new BINTERNAL item to the page, with and * without the index value. */ #define BINTERNAL_SIZE(len) \ (u_int16_t)DB_ALIGN((len) + SSZA(BINTERNAL, data), sizeof(u_int32_t)) #define BINTERNAL_PSIZE(len) \ (BINTERNAL_SIZE(len) + sizeof(db_indx_t)) /************************************************************************ RECNO INTERNAL PAGE LAYOUT ************************************************************************/ /* * The recno internal entry. */ 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(dbp, pg, indx) \ ((RINTERNAL *)P_ENTRY(dbp, pg, indx)) /* * Page space required to add a new RINTERNAL item to the page, with and * without the index value. */ #define RINTERNAL_SIZE \ (u_int16_t)DB_ALIGN(sizeof(RINTERNAL), sizeof(u_int32_t)) #define RINTERNAL_PSIZE \ (RINTERNAL_SIZE + sizeof(db_indx_t)) struct pglist { db_pgno_t pgno; DB_LSN lsn; }; #if defined(__cplusplus) } #endif #endif /* !_DB_PAGE_H_ */