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-rw-r--r--db2/log/log_put.c484
1 files changed, 484 insertions, 0 deletions
diff --git a/db2/log/log_put.c b/db2/log/log_put.c
new file mode 100644
index 0000000000..db31f9b0e1
--- /dev/null
+++ b/db2/log/log_put.c
@@ -0,0 +1,484 @@
+/*-
+ * See the file LICENSE for redistribution information.
+ *
+ * Copyright (c) 1996, 1997
+ * Sleepycat Software. All rights reserved.
+ */
+#include "config.h"
+
+#ifndef lint
+static const char sccsid[] = "@(#)log_put.c 10.12 (Sleepycat) 8/20/97";
+#endif /* not lint */
+
+#ifndef NO_SYSTEM_INCLUDES
+#include <sys/types.h>
+
+#include <errno.h>
+#include <fcntl.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+#include <unistd.h>
+#endif
+
+#include "db_int.h"
+#include "shqueue.h"
+#include "db_page.h"
+#include "log.h"
+#include "hash.h"
+#include "common_ext.h"
+
+static int __log_fill __P((DB_LOG *, void *, u_int32_t));
+static int __log_newfd __P((DB_LOG *));
+static int __log_write __P((DB_LOG *, void *, u_int32_t));
+static int __log_putr __P((DB_LOG *, const DBT *, u_int32_t));
+
+/*
+ * log_put --
+ * Write a log record.
+ */
+int
+log_put(dblp, lsn, dbt, flags)
+ DB_LOG *dblp;
+ DB_LSN *lsn;
+ const DBT *dbt;
+ int flags;
+{
+ int ret;
+
+ /* Validate arguments. */
+#define OKFLAGS (DB_CHECKPOINT | DB_FLUSH)
+ if (flags != 0) {
+ if ((ret =
+ __db_fchk(dblp->dbenv, "log_put", flags, OKFLAGS)) != 0)
+ return (ret);
+ switch (flags) {
+ case DB_CHECKPOINT:
+ case DB_FLUSH:
+ case 0:
+ break;
+ default:
+ return (__db_ferr(dblp->dbenv, "log_put", 1));
+ }
+ }
+
+ LOCK_LOGREGION(dblp);
+
+ ret = __log_put(dblp, lsn, dbt, flags);
+
+ UNLOCK_LOGREGION(dblp);
+
+ return (ret);
+}
+
+/*
+ * __log_put --
+ * Write a log record; internal version.
+ *
+ * PUBLIC: int __log_put __P((DB_LOG *, DB_LSN *, const DBT *, int));
+ */
+int
+__log_put(dblp, lsn, dbt, flags)
+ DB_LOG *dblp;
+ DB_LSN *lsn;
+ const DBT *dbt;
+ int flags;
+{
+ DBT t;
+ DBT fid_dbt;
+ DB_LSN r_unused;
+ FNAME *fnp;
+ LOG *lp;
+ u_int32_t lastoff;
+ int ret;
+
+ lp = dblp->lp;
+
+ /* If this information won't fit in the file, swap files. */
+ if (lp->lsn.offset + sizeof(HDR) + dbt->size > lp->persist.lg_max) {
+ if (sizeof(HDR) +
+ sizeof(LOGP) + dbt->size > lp->persist.lg_max) {
+ __db_err(dblp->dbenv,
+ "log_put: record larger than maximum file size");
+ return (EINVAL);
+ }
+ if (lp->b_off != 0) {
+ if ((ret = __log_write(dblp, lp->buf, lp->b_off)) != 0)
+ return (ret);
+ if ((ret = __db_fsync(dblp->lfd)) != 0)
+ return (ret);
+ lp->s_lsn.file = lp->lsn.file;
+ lp->s_lsn.offset = lp->lsn.offset - 1;
+ }
+
+ /*
+ * Save the last known offset from the previous file, we'll
+ * need it to initialize the persistent header information.
+ */
+ lastoff = lp->lsn.offset;
+
+ ++lp->lsn.file;
+ lp->lsn.offset = 0;
+ lp->w_off = 0;
+ } else
+ lastoff = 0;
+
+ /*
+ * Insert persistent information as the first record in every file.
+ * Note that the previous length is wrong for the very first record
+ * of the log, but that's okay, we check for it during retrieval.
+ */
+ if (lp->lsn.offset == 0) {
+ t.data = &lp->persist;
+ t.size = sizeof(LOGP);
+ if ((ret = __log_putr(dblp,
+ &t, lastoff == 0 ? 0 : lastoff - lp->len)) != 0)
+ return (ret);
+ }
+
+ /* Initialize the LSN information returned to the user. */
+ lsn->file = lp->lsn.file;
+ lsn->offset = lp->lsn.offset;
+
+ /* Put out the user's record. */
+ if ((ret = __log_putr(dblp, dbt, lp->lsn.offset - lp->len)) != 0)
+ return (ret);
+
+ /*
+ * On a checkpoint, we:
+ * Put out the checkpoint record (above).
+ * Save the LSN of the checkpoint in the shared region.
+ * Append the set of file name information into the log.
+ * Flush the current buffer contents to disk.
+ * Sync the log to disk.
+ * Save the time the checkpoint was written.
+ * Reset the bytes written since the last checkpoint.
+ */
+ if (flags == DB_CHECKPOINT) {
+ lp->c_lsn = *lsn;
+
+ for (fnp = SH_TAILQ_FIRST(&dblp->lp->fq, __fname);
+ fnp != NULL; fnp = SH_TAILQ_NEXT(fnp, q, __fname)) {
+ t.data = ADDR(dblp, fnp->name_off);
+ t.size = strlen(t.data) + 1;
+ memset(&fid_dbt, 0, sizeof(fid_dbt));
+ fid_dbt.data = ADDR(dblp, fnp->fileid_off);
+ fid_dbt.size = DB_FILE_ID_LEN;
+ if ((ret = __log_register_log(dblp, NULL, &r_unused,
+ 0, &t, &fid_dbt, fnp->id, fnp->s_type)) != 0)
+ return (ret);
+ }
+ if (lp->b_off != 0 &&
+ (ret = __log_write(dblp, lp->buf, lp->b_off)) != 0)
+ return (ret);
+ (void)time(&lp->chkpt);
+ lp->written = 0;
+
+ if ((ret = __db_fsync(dblp->lfd)) != 0)
+ return (ret);
+ lp->s_lsn.file = lp->lsn.file;
+ lp->s_lsn.offset = lp->lsn.offset - 1;
+ }
+
+ /* We always flush on a checkpoint. */
+ if (flags == DB_FLUSH || flags == DB_CHECKPOINT) {
+ if (lp->b_off != 0 &&
+ (ret = __log_write(dblp, lp->buf, lp->b_off)) != 0)
+ return (ret);
+
+ if ((ret = __db_fsync(dblp->lfd)) != 0)
+ return (ret);
+ lp->s_lsn.file = lp->lsn.file;
+ lp->s_lsn.offset = lp->lsn.offset - 1;
+ }
+
+ /*
+ * If we just did I/O, i.e., this LSN could have spanned the start of
+ * the in-core buffer, we remember it so that we can flush correctly
+ * during a sync.
+ */
+ if (lsn->offset < lp->w_off && lsn->offset + lp->len > lp->w_off)
+ lp->span_lsn = *lsn;
+ return (0);
+}
+
+/*
+ * __log_putr --
+ * Actually put a record into the log.
+ */
+static int
+__log_putr(dblp, dbt, prev)
+ DB_LOG *dblp;
+ const DBT *dbt;
+ u_int32_t prev;
+{
+ HDR hdr;
+ LOG *lp;
+ int ret;
+
+ lp = dblp->lp;
+
+ /*
+ * Initialize the header. If we just switched files, lsn.offset will
+ * be 0, and what we really want is the offset of the previous record
+ * in the previous file. Fortunately, prev holds the value we want.
+ */
+ hdr.prev = prev;
+ hdr.len = sizeof(HDR) + dbt->size;
+ hdr.cksum = __ham_func4(dbt->data, dbt->size);
+
+ if ((ret = __log_fill(dblp, &hdr, sizeof(HDR))) != 0)
+ return (ret);
+ lp->lsn.offset += sizeof(HDR);
+
+ if ((ret = __log_fill(dblp, dbt->data, dbt->size)) != 0)
+ return (ret);
+ lp->lsn.offset += dbt->size;
+
+ lp->len = sizeof(HDR) + dbt->size;
+ return (0);
+}
+
+/*
+ * log_flush --
+ * Write all records less than or equal to the specified LSN.
+ */
+int
+log_flush(dblp, lsn)
+ DB_LOG *dblp;
+ const DB_LSN *lsn;
+{
+ DB_LSN t_lsn;
+ LOG *lp;
+ int ret;
+
+ ret = 0;
+ lp = dblp->lp;
+
+ LOCK_LOGREGION(dblp);
+
+ /* If no LSN specified, flush the entire log. */
+ if (lsn == NULL) {
+ t_lsn.file = lp->lsn.file;
+ t_lsn.offset = lp->lsn.offset - lp->len;
+ lsn = &t_lsn;
+ }
+
+ /* If it's a non-existent record, it's an error. */
+ if (lsn->file > lp->lsn.file ||
+ (lsn->file == lp->lsn.file && lsn->offset > lp->lsn.offset)) {
+ __db_err(dblp->dbenv, "log_flush: LSN past current end-of-log");
+ ret = EINVAL;
+ goto ret1;
+ }
+
+ /*
+ * If it's from a previous file, we're done because we sync each
+ * file when we move to a new one.
+ */
+ if (lsn->file < lp->lsn.file)
+ goto ret1;
+
+ /*
+ * If it's less than the last-sync'd offset, we've already sync'd
+ * this LSN.
+ */
+ if (lsn->offset <= lp->s_lsn.offset)
+ goto ret1;
+
+ /*
+ * We may need to write the current buffer. We have to write the
+ * current buffer if the sync LSN is greater than or equal to the
+ * saved spanning-LSN.
+ */
+ if (lsn->file >= lp->span_lsn.file &&
+ lsn->offset >= lp->span_lsn.offset)
+ if ((ret = __log_write(dblp, lp->buf, lp->b_off)) != 0)
+ goto ret1;
+
+ /* Acquire a file descriptor if we don't have one. */
+ if (dblp->lfname != dblp->lp->lsn.file &&
+ (ret = __log_newfd(dblp)) != 0)
+ goto ret1;
+
+ if ((ret = __db_fsync(dblp->lfd)) != 0)
+ goto ret1;
+
+ lp->s_lsn.file = lp->lsn.file;
+ lp->s_lsn.offset = lsn->offset;
+
+ret1: UNLOCK_LOGREGION(dblp);
+ return (ret);
+}
+
+/*
+ * __log_fill --
+ * Write information into the log.
+ */
+static int
+__log_fill(dblp, addr, len)
+ DB_LOG *dblp;
+ void *addr;
+ u_int32_t len;
+{
+ LOG *lp;
+ u_int32_t nrec;
+ size_t nw, remain;
+ int ret;
+
+ /* Copy out the data. */
+ for (lp = dblp->lp; len > 0;) {
+ /*
+ * If we're on a buffer boundary and the data is big enough,
+ * copy as many records as we can directly from the data.
+ */
+ if (lp->b_off == 0 && len >= sizeof(lp->buf)) {
+ nrec = len / sizeof(lp->buf);
+ if ((ret = __log_write(dblp,
+ addr, nrec * sizeof(lp->buf))) != 0)
+ return (ret);
+ addr = (u_int8_t *)addr + nrec * sizeof(lp->buf);
+ len -= nrec * sizeof(lp->buf);
+ continue;
+ }
+
+ /* Figure out how many bytes we can copy this time. */
+ remain = sizeof(lp->buf) - lp->b_off;
+ nw = remain > len ? len : remain;
+ memcpy(lp->buf + lp->b_off, addr, nw);
+ addr = (u_int8_t *)addr + nw;
+ len -= nw;
+ lp->b_off += nw;
+
+ /* If we fill the buffer, flush it. */
+ if (lp->b_off == sizeof(lp->buf) &&
+ (ret = __log_write(dblp, lp->buf, sizeof(lp->buf))) != 0)
+ return (ret);
+ }
+ return (0);
+}
+
+/*
+ * __log_write --
+ * Write the log buffer to disk.
+ */
+static int
+__log_write(dblp, addr, len)
+ DB_LOG *dblp;
+ void *addr;
+ u_int32_t len;
+{
+ LOG *lp;
+ ssize_t nw;
+ int ret;
+
+ /*
+ * If we haven't opened the log file yet or the current one
+ * has changed, acquire a new log file.
+ */
+ lp = dblp->lp;
+ if (dblp->lfd == -1 || dblp->lfname != lp->lsn.file)
+ if ((ret = __log_newfd(dblp)) != 0)
+ return (ret);
+
+ /*
+ * Seek to the offset in the file (someone may have written it
+ * since we last did).
+ */
+ if ((ret = __db_lseek(dblp->lfd, 0, 0, lp->w_off, SEEK_SET)) != 0)
+ return (ret);
+ if ((ret = __db_write(dblp->lfd, addr, len, &nw)) != 0)
+ return (ret);
+ if (nw != (int32_t)len)
+ return (EIO);
+
+ /* Update the seek offset and reset the buffer offset. */
+ lp->b_off = 0;
+ lp->w_off += len;
+ lp->written += len;
+
+ return (0);
+}
+
+/*
+ * log_file --
+ * Map a DB_LSN to a file name.
+ */
+int
+log_file(dblp, lsn, namep, len)
+ DB_LOG *dblp;
+ const DB_LSN *lsn;
+ char *namep;
+ size_t len;
+{
+ int ret;
+ char *p;
+
+ LOCK_LOGREGION(dblp);
+
+ ret = __log_name(dblp->dbenv, lsn->file, &p);
+
+ UNLOCK_LOGREGION(dblp);
+
+ if (ret != 0)
+ return (ret);
+
+ /* Check to make sure there's enough room and copy the name. */
+ if (len < strlen(p)) {
+ *namep = '\0';
+ return (ENOMEM);
+ }
+ (void)strcpy(namep, p);
+ free(p);
+
+ return (0);
+}
+
+/*
+ * __log_newfd --
+ * Acquire a file descriptor for the current log file.
+ */
+static int
+__log_newfd(dblp)
+ DB_LOG *dblp;
+{
+ int ret;
+ char *p;
+
+ /* Close any previous file descriptor. */
+ if (dblp->lfd != -1) {
+ (void)__db_close(dblp->lfd);
+ dblp->lfd = -1;
+ }
+
+ /* Get the path of the new file and open it. */
+ dblp->lfname = dblp->lp->lsn.file;
+ if ((ret = __log_name(dblp->dbenv, dblp->lfname, &p)) != 0)
+ return (ret);
+ if ((ret = __db_fdopen(p,
+ DB_CREATE | DB_SEQUENTIAL,
+ DB_CREATE | DB_SEQUENTIAL,
+ dblp->lp->persist.mode, &dblp->lfd)) != 0)
+ __db_err(dblp->dbenv,
+ "log_put: %s: %s", p, strerror(errno));
+ FREES(p);
+ return (ret);
+}
+
+/*
+ * __log_name --
+ * Return the log name for a particular file.
+ *
+ * PUBLIC: int __log_name __P((DB_ENV *, int, char **));
+ */
+int
+__log_name(dbenv, fn, np)
+ DB_ENV *dbenv;
+ int fn;
+ char **np;
+{
+ char name[sizeof(LFNAME) + 10];
+
+ (void)snprintf(name, sizeof(name), LFNAME, fn);
+ return (__db_appname(dbenv, DB_APP_LOG, NULL, name, NULL, np));
+}