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Diffstat (limited to 'db-4.8.30/os/os_seek.c')
-rw-r--r--db-4.8.30/os/os_seek.c64
1 files changed, 64 insertions, 0 deletions
diff --git a/db-4.8.30/os/os_seek.c b/db-4.8.30/os/os_seek.c
new file mode 100644
index 0000000..7c9c9e9
--- /dev/null
+++ b/db-4.8.30/os/os_seek.c
@@ -0,0 +1,64 @@
+/*-
+ * See the file LICENSE for redistribution information.
+ *
+ * Copyright (c) 1997-2009 Oracle. All rights reserved.
+ *
+ * $Id$
+ */
+
+#include "db_config.h"
+
+#include "db_int.h"
+
+/*
+ * __os_seek --
+ * Seek to a page/byte offset in the file.
+ *
+ * PUBLIC: int __os_seek __P((ENV *,
+ * PUBLIC: DB_FH *, db_pgno_t, u_int32_t, u_int32_t));
+ */
+int
+__os_seek(env, fhp, pgno, pgsize, relative)
+ ENV *env;
+ DB_FH *fhp;
+ db_pgno_t pgno;
+ u_int32_t pgsize;
+ u_int32_t relative;
+{
+ DB_ENV *dbenv;
+ off_t offset;
+ int ret;
+
+ dbenv = env == NULL ? NULL : env->dbenv;
+
+ DB_ASSERT(env, F_ISSET(fhp, DB_FH_OPENED) && fhp->fd != -1);
+
+#if defined(HAVE_STATISTICS)
+ ++fhp->seek_count;
+#endif
+
+ offset = (off_t)pgsize * pgno + relative;
+
+ if (dbenv != NULL && FLD_ISSET(dbenv->verbose, DB_VERB_FILEOPS_ALL))
+ __db_msg(env,
+ "fileops: seek %s to %lu", fhp->name, (u_long)offset);
+
+ if (DB_GLOBAL(j_seek) != NULL)
+ ret = DB_GLOBAL(j_seek)(fhp->fd, offset, SEEK_SET);
+ else
+ RETRY_CHK((lseek(
+ fhp->fd, offset, SEEK_SET) == -1 ? 1 : 0), ret);
+
+ if (ret == 0) {
+ fhp->pgsize = pgsize;
+ fhp->pgno = pgno;
+ fhp->offset = relative;
+ } else {
+ __db_syserr(env, ret,
+ "seek: %lu: (%lu * %lu) + %lu", (u_long)offset,
+ (u_long)pgno, (u_long)pgsize, (u_long)relative);
+ ret = __os_posix_err(ret);
+ }
+
+ return (ret);
+}