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Diffstat (limited to 'db/include/log.h')
| -rw-r--r-- | db/include/log.h | 208 |
1 files changed, 208 insertions, 0 deletions
diff --git a/db/include/log.h b/db/include/log.h new file mode 100644 index 000000000..08c2b8076 --- /dev/null +++ b/db/include/log.h @@ -0,0 +1,208 @@ +/*- + * See the file LICENSE for redistribution information. + * + * Copyright (c) 1996, 1997, 1998, 1999, 2000 + * Sleepycat Software. All rights reserved. + * + * $Id: log.h,v 11.19 2001/01/11 18:19:52 bostic Exp $ + */ + +#ifndef _LOG_H_ +#define _LOG_H_ + +struct __db_log; typedef struct __db_log DB_LOG; +struct __fname; typedef struct __fname FNAME; +struct __hdr; typedef struct __hdr HDR; +struct __log; typedef struct __log LOG; +struct __log_persist; typedef struct __log_persist LOGP; + +#define LFPREFIX "log." /* Log file name prefix. */ +#define LFNAME "log.%010d" /* Log file name template. */ +#define LFNAME_V1 "log.%05d" /* Log file name template, rev 1. */ + +#define LG_MAX_DEFAULT (10 * MEGABYTE) /* 10 MB. */ +#define LG_BSIZE_DEFAULT (32 * 1024) /* 32 KB. */ +#define LG_BASE_REGION_SIZE (60 * 1024) /* 60 KB. */ + +/* + * The per-process table that maps log file-id's to DB structures. + */ +typedef struct __db_entry { + TAILQ_HEAD(dblist, __db) dblist; /* Associated DB structures. */ + u_int32_t refcount; /* Reference counted. */ + u_int32_t count; /* Number of ops on a deleted db. */ + int deleted; /* File was not found during open. */ +} DB_ENTRY; + +/* + * DB_LOG + * Per-process log structure. + */ +struct __db_log { +/* + * These fields need to be protected for multi-threaded support. + * + * !!! + * As this structure is allocated in per-process memory, the mutex may need + * to be stored elsewhere on architectures unable to support mutexes in heap + * memory, e.g., HP/UX 9. + */ + MUTEX *mutexp; /* Mutex for thread protection. */ + + DB_ENTRY *dbentry; /* Recovery file-id mapping. */ +#define DB_GROW_SIZE 64 + int32_t dbentry_cnt; /* Entries. Grows by DB_GROW_SIZE. */ + +/* + * These fields are always accessed while the region lock is held, so they do + * not have to be protected by the thread lock as well, OR, they are only used + * when threads are not being used, i.e. most cursor operations are disallowed + * on threaded logs. + */ + u_int32_t lfname; /* Log file "name". */ + DB_FH lfh; /* Log file handle. */ + + DB_LSN c_lsn; /* Cursor: current LSN. */ + DBT c_dbt; /* Cursor: return DBT structure. */ + DB_FH c_fh; /* Cursor: file handle. */ + FILE *c_fp; /* Cursor: file pointer. */ + u_int32_t c_off; /* Cursor: previous record offset. */ + u_int32_t c_len; /* Cursor: current record length. */ + u_int32_t r_file; /* Cursor: current read file */ + u_int32_t r_off; /* Cursor: offset of read buffer. */ + u_int32_t r_size; /* Cursor: size of data in read buf. */ + + u_int8_t *bufp; /* Region buffer. */ + u_int8_t *readbufp; /* Read buffer. */ + +/* These fields are not protected. */ + DB_ENV *dbenv; /* Reference to error information. */ + REGINFO reginfo; /* Region information. */ + +/* + * These fields are used by XA; since XA forbids threaded execution, these + * do not have to be protected. + */ + void *xa_info; /* Committed transaction list that + * has to be carried between calls + * to xa_recover. */ + DB_LSN xa_lsn; /* Position of an XA recovery scan. */ + DB_LSN xa_first; /* LSN to which we need to roll back + for this XA recovery scan. */ + +#define DBLOG_RECOVER 0x01 /* We are in recovery. */ +#define DBLOG_FORCE_OPEN 0x02 /* Force the db open even + * if it appears to be deleted. + */ + u_int32_t flags; +}; + +/* + * HDR -- + * Log record header. + */ +struct __hdr { + u_int32_t prev; /* Previous offset. */ + u_int32_t cksum; /* Current checksum. */ + u_int32_t len; /* Current length. */ +}; + +struct __log_persist { + u_int32_t magic; /* DB_LOGMAGIC */ + u_int32_t version; /* DB_LOGVERSION */ + + u_int32_t lg_max; /* Maximum file size. */ + int mode; /* Log file mode. */ +}; + +/* + * LOG -- + * Shared log region. One of these is allocated in shared memory, + * and describes the log. + */ +struct __log { + LOGP persist; /* Persistent information. */ + + SH_TAILQ_HEAD(__fq) fq; /* List of file names. */ + + /* + * The lsn LSN is the file offset that we're about to write and which + * we will return to the user. + */ + DB_LSN lsn; /* LSN at current file offset. */ + + /* + * The s_lsn LSN is the last LSN that we know is on disk, not just + * written, but synced. + */ + DB_LSN s_lsn; /* LSN of the last sync. */ + + u_int32_t len; /* Length of the last record. */ + + u_int32_t w_off; /* Current write offset in the file. */ + + DB_LSN chkpt_lsn; /* LSN of the last checkpoint. */ + time_t chkpt; /* Time of the last checkpoint. */ + + DB_LOG_STAT stat; /* Log statistics. */ + + /* + * The f_lsn LSN is the LSN (returned to the user) that "owns" the + * first byte of the buffer. If the record associated with the LSN + * spans buffers, it may not reflect the physical file location of + * the first byte of the buffer. + */ + DB_LSN f_lsn; /* LSN of first byte in the buffer. */ + size_t b_off; /* Current offset in the buffer. */ + + roff_t buffer_off; /* Log buffer offset. */ + u_int32_t buffer_size; /* Log buffer size. */ +}; + +/* + * FNAME -- + * File name and id. + */ +struct __fname { + SH_TAILQ_ENTRY q; /* File name queue. */ + + u_int16_t ref; /* Reference count. */ + u_int16_t locked; /* Table is locked. */ + + int32_t id; /* Logging file id. */ + DBTYPE s_type; /* Saved DB type. */ + + roff_t name_off; /* Name offset. */ + db_pgno_t meta_pgno; /* Page number of the meta page. */ + u_int8_t ufid[DB_FILE_ID_LEN]; /* Unique file id. */ +}; + +/* File open/close register log record opcodes. */ +#define LOG_CHECKPOINT 1 /* Checkpoint: file name/id dump. */ +#define LOG_CLOSE 2 /* File close. */ +#define LOG_OPEN 3 /* File open. */ + +#define CHECK_LSN(redo, cmp, lsn, prev) \ + DB_ASSERT(!DB_REDO(redo) || (cmp) >= 0); \ + if (DB_REDO(redo) && (cmp) < 0) { \ + __db_err(dbenv, \ + "Log sequence error: page LSN %lu:%lu; previous LSN %lu %lu", \ + (u_long)(lsn)->file, (u_long)(lsn)->offset, \ + (u_long)(prev)->file, (u_long)(prev)->offset); \ + goto out; \ + } + +/* + * Status codes indicating the validity of a log file examined by + * __log_valid(). + */ +typedef enum { + DB_LV_INCOMPLETE, + DB_LV_NORMAL, + DB_LV_OLD_READABLE, + DB_LV_OLD_UNREADABLE +} logfile_validity; + +#include "log_auto.h" +#include "log_ext.h" +#endif /* _LOG_H_ */ |