diff options
Diffstat (limited to 'e2fsprogs/old_e2fsprogs/ext2fs/flushb.c')
-rw-r--r-- | e2fsprogs/old_e2fsprogs/ext2fs/flushb.c | 83 |
1 files changed, 83 insertions, 0 deletions
diff --git a/e2fsprogs/old_e2fsprogs/ext2fs/flushb.c b/e2fsprogs/old_e2fsprogs/ext2fs/flushb.c new file mode 100644 index 0000000..e429826 --- /dev/null +++ b/e2fsprogs/old_e2fsprogs/ext2fs/flushb.c @@ -0,0 +1,83 @@ +/* vi: set sw=4 ts=4: */ +/* + * flushb.c --- Hides system-dependent information for both syncing a + * device to disk and to flush any buffers from disk cache. + * + * Copyright (C) 2000 Theodore Ts'o. + * + * %Begin-Header% + * This file may be redistributed under the terms of the GNU Public + * License. + * %End-Header% + */ + +#include <stdio.h> +#if HAVE_ERRNO_H +#include <errno.h> +#endif +#if HAVE_UNISTD_H +#include <unistd.h> +#endif +#if HAVE_SYS_IOCTL_H +#include <sys/ioctl.h> +#endif +#if HAVE_SYS_MOUNT_H +#include <sys/param.h> +#include <sys/mount.h> /* This may define BLKFLSBUF */ +#endif + +#include "ext2_fs.h" +#include "ext2fs.h" + +/* + * For Linux, define BLKFLSBUF and FDFLUSH if necessary, since + * not all portable header file does so for us. This really should be + * fixed in the glibc header files. (Recent glibcs appear to define + * BLKFLSBUF in sys/mount.h, but FDFLUSH still doesn't seem to be + * defined anywhere portable.) Until then.... + */ +#ifdef __linux__ +#ifndef BLKFLSBUF +#define BLKFLSBUF _IO(0x12,97) /* flush buffer cache */ +#endif +#ifndef FDFLUSH +#define FDFLUSH _IO(2,0x4b) /* flush floppy disk */ +#endif +#endif + +/* + * This function will sync a device/file, and optionally attempt to + * flush the buffer cache. The latter is basically only useful for + * system benchmarks and for torturing systems in burn-in tests. :) + */ +errcode_t ext2fs_sync_device(int fd, int flushb) +{ + /* + * We always sync the device in case we're running on old + * kernels for which we can lose data if we don't. (There + * still is a race condition for those kernels, but this + * reduces it greatly.) + */ + if (fsync (fd) == -1) + return errno; + + if (flushb) { + +#ifdef BLKFLSBUF + if (ioctl (fd, BLKFLSBUF, 0) == 0) + return 0; +#else +#ifdef __GNUC__ +# warning BLKFLSBUF not defined +#endif /* __GNUC__ */ +#endif +#ifdef FDFLUSH + ioctl (fd, FDFLUSH, 0); /* In case this is a floppy */ +#else +#ifdef __GNUC__ +# warning FDFLUSH not defined +#endif /* __GNUC__ */ +#endif + } + return 0; +} |