1 /* vi: set sw=4 ts=4: */
3 * Mini swapon/swapoff implementation for busybox
5 * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
7 * Licensed under GPLv2, see file LICENSE in this source tree.
10 //usage:#define swapon_trivial_usage
11 //usage: "[-a]" IF_FEATURE_SWAPON_PRI(" [-p PRI]") " [DEVICE]"
12 //usage:#define swapon_full_usage "\n\n"
13 //usage: "Start swapping on DEVICE\n"
14 //usage: "\n -a Start swapping on all swap devices"
15 //usage: IF_FEATURE_SWAPON_PRI(
16 //usage: "\n -p PRI Set swap device priority"
19 //usage:#define swapoff_trivial_usage
20 //usage: "[-a] [DEVICE]"
21 //usage:#define swapoff_full_usage "\n\n"
22 //usage: "Stop swapping on DEVICE\n"
23 //usage: "\n -a Stop swapping on all swap devices"
28 # include <sys/swap.h>
31 #if ENABLE_FEATURE_MOUNT_LABEL
32 # include "volume_id.h"
34 # define resolve_mount_spec(fsname) ((void)0)
38 # define MNTTYPE_SWAP "swap"
41 #if ENABLE_FEATURE_SWAPON_PRI
45 #define G (*(struct globals*)&bb_common_bufsiz1)
46 #define g_flags (G.flags)
50 #define INIT_G() do { } while (0)
52 static int swap_enable_disable(char *device)
57 resolve_mount_spec(&device);
62 if (S_ISREG(st.st_mode))
63 if (st.st_blocks * (off_t)512 < st.st_size)
64 bb_error_msg("warning: swap file has holes");
67 if (applet_name[5] == 'n')
68 status = swapon(device, g_flags);
70 status = swapoff(device);
73 bb_simple_perror_msg(device);
80 static int do_em_all(void)
86 f = setmntent("/etc/fstab", "r");
88 bb_perror_msg_and_die("/etc/fstab");
91 while ((m = getmntent(f)) != NULL) {
92 if (strcmp(m->mnt_type, MNTTYPE_SWAP) == 0) {
93 /* swapon -a should ignore entries with noauto,
94 * but swapoff -a should process them */
95 if (applet_name[5] != 'n'
96 || hasmntopt(m, MNTOPT_NOAUTO) == NULL
98 #if ENABLE_FEATURE_SWAPON_PRI
100 g_flags = 0; /* each swap space might have different flags */
101 p = strstr(m->mnt_opts, "pri=");
103 /* Max allowed 32767 (==SWAP_FLAG_PRIO_MASK) */
104 int swap_prio = MIN(bb_strtoull(p + 4 , NULL, 10), SWAP_FLAG_PRIO_MASK);
105 /* We want to allow "NNNN,foo", thus errno == EINVAL is allowed too */
106 if (errno != ERANGE) {
107 g_flags = SWAP_FLAG_PREFER |
108 (swap_prio << SWAP_FLAG_PRIO_SHIFT);
112 err += swap_enable_disable(m->mnt_fsname);
117 if (ENABLE_FEATURE_CLEAN_UP)
123 int swap_on_off_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
124 int swap_on_off_main(int argc UNUSED_PARAM, char **argv)
130 #if !ENABLE_FEATURE_SWAPON_PRI
131 ret = getopt32(argv, "a");
133 if (applet_name[5] == 'n')
134 opt_complementary = "p+";
135 ret = getopt32(argv, (applet_name[5] == 'n') ? "ap:" : "a", &g_flags);
138 g_flags = SWAP_FLAG_PREFER |
139 ((g_flags & SWAP_FLAG_PRIO_MASK) << SWAP_FLAG_PRIO_SHIFT);
144 if (ret /* & 1: not needed */) // -a
151 /* ret = 0; redundant */
153 ret += swap_enable_disable(*argv);