create a document for mdev so people dont have to rtfs

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

diff --git a/util-linux/swaponoff.c b/util-linux/swaponoff.c
index bb8395fa4aa414c4cb185fb2faca23f23170f898..e1de4eb0ce9cbd8689ed0df3cfdc7d6b685bfd26 100644 (file)
--- a/util-linux/swaponoff.c
+++ b/util-linux/swaponoff.c
@@ -2,136 +2,77 @@
 /*
  * Mini swapon/swapoff implementation for busybox
  *
+ * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
  *
- * Copyright (C) 1999,2000 by Lineo, inc.
- * Written by Erik Andersen <andersen@lineo.com>, <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
- *
+ * Licensed under the GPL version 2, see the file LICENSE in this tarball.
  */
 
-#include "internal.h"
-#include <stdio.h>
-#include <sys/mount.h>
+#include "busybox.h"
 #include <mntent.h>
-#include <dirent.h>
-#include <errno.h>
-#include <sys/syscall.h>
-
-_syscall2(int, swapon, const char *, path, int, flags);
-_syscall1(int, swapoff, const char *, path);
-
-
-static int whichApp;
-static const char *appName;
-
-static const char swapoff_usage[] =
-       "swapoff [OPTION] [device]\n"
-#ifndef BB_FEATURE_TRIVIAL_HELP
-       "\nStop swapping virtual memory pages on the given device.\n\n"
-       "Options:\n"
-       "\t-a\tStop swapping on all swap devices\n"
-#endif
-       ;
-
-static const char swapon_usage[] =
-       "swapon [OPTION] [device]\n"
-#ifndef BB_FEATURE_TRIVIAL_HELP
-       "\nStart swapping virtual memory pages on the given device.\n\n"
-       "Options:\n"
-       "\t-a\tStart swapping on all swap devices\n"
-#endif
-       ;
-
-
-#define SWAPON_APP   1
-#define SWAPOFF_APP  2
+#include <sys/swap.h>
 
 
-static void swap_enable_disable(char *device)
+static int swap_enable_disable(char *device)
 {
        int status;
+       struct stat st;
 
-       if (whichApp == SWAPON_APP)
+       xstat(device, &st);
+
+       /* test for holes */
+       if (S_ISREG(st.st_mode))
+               if (st.st_blocks * 512 < st.st_size)
+                       bb_error_msg_and_die("swap file has holes");
+
+       if (applet_name[5] == 'n')
                status = swapon(device, 0);
        else
                status = swapoff(device);
 
        if (status != 0) {
-               perror(appName);
-               exit(FALSE);
+               bb_perror_msg("%s", device);
+               return 1;
        }
+
+       return 0;
 }
 
-static void do_em_all()
+static int do_em_all(void)
 {
        struct mntent *m;
-       FILE *f = setmntent("/etc/fstab", "r");
+       FILE *f;
+       int err;
+
+       f = setmntent("/etc/fstab", "r");
+       if (f == NULL)
+               bb_perror_msg_and_die("/etc/fstab");
+
+       err = 0;
+       while ((m = getmntent(f)) != NULL)
+               if (strcmp(m->mnt_type, MNTTYPE_SWAP) == 0)
+                       err += swap_enable_disable(m->mnt_fsname);
 
-       if (f == NULL) {
-               perror("/etc/fstab");
-               exit(FALSE);
-       }
-       while ((m = getmntent(f)) != NULL) {
-               if (strcmp(m->mnt_type, MNTTYPE_SWAP)==0) {
-                       swap_enable_disable(m->mnt_fsname);
-               }
-       }
        endmntent(f);
-       exit(TRUE);
+
+       return err;
 }
 
+#define DO_ALL    0x01
 
-extern int swap_on_off_main(int argc, char **argv)
+int swap_on_off_main(int argc, char **argv);
+int swap_on_off_main(int argc, char **argv)
 {
-       if (strcmp(*argv, "swapon") == 0) {
-               appName = *argv;
-               whichApp = SWAPON_APP;
+       int ret;
 
-       } else {
-               appName = *argv;
-               whichApp = SWAPOFF_APP;
-       }
+       if (argc == 1)
+               bb_show_usage();
 
-       if (argc != 2) {
-               goto usage_and_exit;
-       }
-       argc--;
-       argv++;
-
-       /* Parse any options */
-       while (**argv == '-') {
-               while (*++(*argv))
-                       switch (**argv) {
-                       case 'a':
-                               {
-                                       struct stat statBuf;
-
-                                       if (stat("/etc/fstab", &statBuf) < 0)
-                                               fatalError("/etc/fstab file missing\n");
-                               }
-                               do_em_all();
-                               break;
-                       default:
-                               goto usage_and_exit;
-                       }
-       }
-       swap_enable_disable(*argv);
-       exit(TRUE);
+       ret = getopt32(argc, argv, "a");
+       if (ret & DO_ALL)
+               return do_em_all();
 
-  usage_and_exit:
-       usage((whichApp == SWAPON_APP) ? swapon_usage : swapoff_usage);
-       exit(FALSE);
+       ret = 0;
+       while (*++argv)
+               ret += swap_enable_disable(*argv);
+       return ret;
 }