don't whine if all we need to do is remove a bg job
[oweals/busybox.git] / swaponoff.c
1 /* vi: set sw=4 ts=4: */
2 /*
3  * Mini swapon/swapoff implementation for busybox
4  *
5  *
6  * Copyright (C) 1999,2000,2001 by Lineo, inc.
7  * Written by Erik Andersen <andersen@lineo.com>, <andersee@debian.org>
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License as published by
11  * the Free Software Foundation; either version 2 of the License, or
12  * (at your option) any later version.
13  *
14  * This program is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17  * General Public License for more details.
18  *
19  * You should have received a copy of the GNU General Public License
20  * along with this program; if not, write to the Free Software
21  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
22  *
23  */
24
25 #include <stdio.h>
26 #include <mntent.h>
27 #include <dirent.h>
28 #include <errno.h>
29 #include <string.h>
30 #include <stdlib.h>
31 #include <sys/mount.h>
32
33 #if __GNU_LIBRARY__ < 5
34 /* libc5 doesn't have sys/swap.h, define these here. */ 
35 extern int swapon (__const char *__path, int __flags);
36 extern int swapoff (__const char *__path);
37 #else
38 #include <sys/swap.h>
39 #endif
40
41 #include "busybox.h"
42
43 static int whichApp;
44
45 static const int SWAPON_APP = 1;
46 static const int SWAPOFF_APP = 2;
47
48
49 static void swap_enable_disable(char *device)
50 {
51         int status;
52
53         if (whichApp == SWAPON_APP)
54                 status = swapon(device, 0);
55         else
56                 status = swapoff(device);
57
58         if (status != 0)
59                 perror_msg_and_die(applet_name);
60 }
61
62 static void do_em_all()
63 {
64         struct mntent *m;
65         FILE *f = setmntent("/etc/fstab", "r");
66
67         if (f == NULL)
68                 perror_msg_and_die("/etc/fstab");
69         while ((m = getmntent(f)) != NULL) {
70                 if (strcmp(m->mnt_type, MNTTYPE_SWAP)==0) {
71                         swap_enable_disable(m->mnt_fsname);
72                 }
73         }
74         endmntent(f);
75         exit(EXIT_SUCCESS);
76 }
77
78
79 extern int swap_on_off_main(int argc, char **argv)
80 {
81         if (strcmp(applet_name, "swapon") == 0) {
82                 whichApp = SWAPON_APP;
83         } else {
84                 whichApp = SWAPOFF_APP;
85         }
86
87         if (argc != 2) {
88                 goto usage_and_exit;
89         }
90         argc--;
91         argv++;
92
93         /* Parse any options */
94         while (**argv == '-') {
95                 while (*++(*argv))
96                         switch (**argv) {
97                         case 'a':
98                                 {
99                                         struct stat statBuf;
100
101                                         if (stat("/etc/fstab", &statBuf) < 0)
102                                                 error_msg_and_die("/etc/fstab file missing");
103                                 }
104                                 do_em_all();
105                                 break;
106                         default:
107                                 goto usage_and_exit;
108                         }
109         }
110         swap_enable_disable(*argv);
111         return EXIT_SUCCESS;
112
113   usage_and_exit:
114         show_usage();
115 }