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-rw-r--r--db2/include/log.h157
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diff --git a/db2/include/log.h b/db2/include/log.h
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+/*-
+ * See the file LICENSE for redistribution information.
+ *
+ * Copyright (c) 1996, 1997
+ * Sleepycat Software. All rights reserved.
+ *
+ * @(#)log.h 10.8 (Sleepycat) 8/18/97
+ */
+
+#ifndef _LOG_H_
+#define _LOG_H_
+
+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 MAXLFNAME 99999 /* Maximum log file name. */
+#define LFNAME "log.%05d" /* Log file name template. */
+
+ /* Default log name. */
+#define DB_DEFAULT_LOG_FILE "__db_log.share"
+
+#define DEFAULT_MAX (10 * 1048576) /* 10 Mb. */
+
+/* Macros to return per-process address, offsets. */
+#define ADDR(base, offset) ((void *)((u_int8_t *)((base)->addr) + offset))
+#define OFFSET(base, p) ((u_int8_t *)(p) - (u_int8_t *)(base)->addr)
+
+/* Macros to lock/unlock the region and threads. */
+#define LOCK_LOGTHREAD(dblp) \
+ if (F_ISSET(dblp, DB_AM_THREAD)) \
+ (void)__db_mutex_lock(&(dblp)->mutex, -1, \
+ (dblp)->dbenv == NULL ? NULL : (dblp)->dbenv->db_yield)
+#define UNLOCK_LOGTHREAD(dblp) \
+ if (F_ISSET(dblp, DB_AM_THREAD)) \
+ (void)__db_mutex_unlock(&(dblp)->mutex, -1);
+#define LOCK_LOGREGION(dblp) \
+ (void)__db_mutex_lock(&((RLAYOUT *)(dblp)->lp)->lock, \
+ (dblp)->fd, (dblp)->dbenv == NULL ? NULL : (dblp)->dbenv->db_yield)
+#define UNLOCK_LOGREGION(dblp) \
+ (void)__db_mutex_unlock(&((RLAYOUT *)(dblp)->lp)->lock, (dblp)->fd)
+
+/*
+ * The per-process table that maps log file-id's to DB structures.
+ */
+typedef struct __db_entry {
+ DB *dbp; /* Associated DB structure. */
+ int refcount; /* Reference counted. */
+ 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. */
+ db_mutex_t mutex; /* Mutex for thread protection. */
+
+ DB_ENTRY *dbentry; /* Recovery file-id mapping. */
+#define DB_GROW_SIZE 64
+ u_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". */
+ int lfd; /* Log file descriptor. */
+
+ DB_LSN c_lsn; /* Cursor: current LSN. */
+ DBT c_dbt; /* Cursor: return DBT structure. */
+ int c_fd; /* Cursor: file descriptor. */
+ u_int32_t c_off; /* Cursor: previous record offset. */
+ u_int32_t c_len; /* Cursor: current record length. */
+
+/* These fields are not protected. */
+ LOG *lp; /* Address of the shared LOG. */
+
+ DB_ENV *dbenv; /* Reference to error information. */
+
+ void *maddr; /* Address of mmap'd region. */
+ void *addr; /* Address of shalloc() region. */
+ int fd; /* Region file descriptor. */
+
+ u_int32_t flags; /* Support the DB_AM_XXX 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 {
+ RLAYOUT rlayout; /* General region information. */
+
+ LOGP persist; /* Persistent information. */
+
+ SH_TAILQ_HEAD(__fq) fq; /* List of file names. */
+
+ DB_LSN lsn; /* LSN at current file offset. */
+ DB_LSN c_lsn; /* LSN of the last checkpoint. */
+ DB_LSN s_lsn; /* LSN of the last sync. */
+ DB_LSN span_lsn; /* LSN spanning buffer write. */
+
+ u_int32_t len; /* Length of the last record. */
+
+ size_t b_off; /* Current offset in the buffer. */
+ u_int32_t w_off; /* Current write offset in the file. */
+
+ time_t chkpt; /* Time of the last checkpoint. */
+ u_int32_t written; /* Bytes written since checkpoint. */
+
+ u_int8_t buf[4 * 1024]; /* Log buffer. */
+};
+
+/*
+ * FNAME --
+ * File name and id.
+ */
+struct __fname {
+ SH_TAILQ_ENTRY q; /* File name queue. */
+
+ u_int16_t ref; /* Reference count. */
+
+ u_int32_t id; /* Logging file id. */
+ DBTYPE s_type; /* Saved DB type. */
+
+ u_int32_t fileid_off; /* Unique file id offset. */
+
+ size_t name_off; /* Name offset. */
+};
+
+#include "log_auto.h"
+#include "log_ext.h"
+#endif /* _LOG_H_ */