mount: make it more readable

[oweals/busybox.git] / util-linux / freeramdisk.c

diff --git a/util-linux/freeramdisk.c b/util-linux/freeramdisk.c
index 64915b313251dcdba33e6ccc094a1287d6bdbe28..bde6afc0a7914d2ef808a7321f5f6644235c7e77 100644 (file)
--- a/util-linux/freeramdisk.c
+++ b/util-linux/freeramdisk.c
@@ -1,64 +1,33 @@
 /* vi: set sw=4 ts=4: */
 /*
- * freeramdisk implementation for busybox
+ * freeramdisk and fdflush implementations for busybox
  *
  * Copyright (C) 2000 and written by Emanuele Caratti <wiz@iol.it>
- * Adjusted a bit by Erik Andersen <andersee@debian.org>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- * General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ * Adjusted a bit by Erik Andersen <andersen@codepoet.org>
+ * Unified with fdflush by Tito Ragusa <farmatito@tiscali.it>
  *
+ * Licensed under GPLv2, see file LICENSE in this tarball for details.
  */
 
-#include <stdio.h>
-#include <string.h>
-#include <sys/types.h>
-#include <fcntl.h>
-#include <sys/ioctl.h>
-#include <errno.h>
-#include "internal.h"
-
+#include "libbb.h"
 
-/* From linux/fs.h */
-#define BLKFLSBUF  _IO(0x12,97)        /* flush buffer cache */
+/* From <linux/fd.h> */
+#define FDFLUSH  _IO(2,0x4b)
 
-extern int
-freeramdisk_main(int argc, char **argv)
+int freeramdisk_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
+int freeramdisk_main(int argc, char **argv)
 {
-       int   f;
+       int fd;
 
-       if (argc != 2 || *argv[1] == '-') {
-               usage(freeramdisk_usage);
-       }
+       if (argc != 2) bb_show_usage();
 
-       if ((f = open(argv[1], O_RDWR)) == -1) {
-               fatalError( "cannot open %s: %s\n", argv[1], strerror(errno));
-       }
-       if (ioctl(f, BLKFLSBUF) < 0) {
-               fatalError( "failed ioctl on %s: %s\n", argv[1], strerror(errno));
-       }
-       /* Don't bother closing.  Exit does
-        * that, so we can save a few bytes */
-       /* close(f); */
-       return(TRUE);
-}
+       fd = xopen(argv[1], O_RDWR);
 
-/*
-Local Variables:
-c-file-style: "linux"
-c-basic-offset: 4
-tab-width: 4
-End:
-*/
+       // Act like freeramdisk, fdflush, or both depending on configuration.
+       ioctl_or_perror_and_die(fd, (ENABLE_FREERAMDISK && applet_name[1]=='r')
+                       || !ENABLE_FDFLUSH ? BLKFLSBUF : FDFLUSH, NULL, "%s", argv[1]);
 
+       if (ENABLE_FEATURE_CLEAN_UP) close(fd);
+
+       return EXIT_SUCCESS;
+}