1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
|
/* vi: set sw=4 ts=4: */
/*
* Mini swapon/swapoff implementation for busybox
*
* Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
*
* Licensed under GPLv2, see file LICENSE in this source tree.
*/
//usage:#define swapon_trivial_usage
//usage: "[-a]" IF_FEATURE_SWAPON_DISCARD(" [-d[POL]]") IF_FEATURE_SWAPON_PRI(" [-p PRI]") " [DEVICE]"
//usage:#define swapon_full_usage "\n\n"
//usage: "Start swapping on DEVICE\n"
//usage: "\n -a Start swapping on all swap devices"
//usage: IF_FEATURE_SWAPON_DISCARD(
//usage: "\n -d[POL] Discard blocks at swapon (POL=once),"
//usage: "\n as freed (POL=pages), or both (POL omitted)"
//usage: )
//usage: IF_FEATURE_SWAPON_PRI(
//usage: "\n -p PRI Set swap device priority"
//usage: )
//usage:
//usage:#define swapoff_trivial_usage
//usage: "[-a] [DEVICE]"
//usage:#define swapoff_full_usage "\n\n"
//usage: "Stop swapping on DEVICE\n"
//usage: "\n -a Stop swapping on all swap devices"
#include "libbb.h"
#include <mntent.h>
#ifndef __BIONIC__
# include <sys/swap.h>
#endif
#if ENABLE_FEATURE_MOUNT_LABEL
# include "volume_id.h"
#else
# define resolve_mount_spec(fsname) ((void)0)
#endif
#ifndef MNTTYPE_SWAP
# define MNTTYPE_SWAP "swap"
#endif
#if ENABLE_FEATURE_SWAPON_DISCARD
#ifndef SWAP_FLAG_DISCARD
#define SWAP_FLAG_DISCARD 0x10000
#endif
#ifndef SWAP_FLAG_DISCARD_ONCE
#define SWAP_FLAG_DISCARD_ONCE 0x20000
#endif
#ifndef SWAP_FLAG_DISCARD_PAGES
#define SWAP_FLAG_DISCARD_PAGES 0x40000
#endif
#define SWAP_FLAG_DISCARD_MASK \
(SWAP_FLAG_DISCARD | SWAP_FLAG_DISCARD_ONCE | SWAP_FLAG_DISCARD_PAGES)
#endif
#if ENABLE_FEATURE_SWAPON_DISCARD || ENABLE_FEATURE_SWAPON_PRI
struct globals {
int flags;
} FIX_ALIASING;
#define G (*(struct globals*)&bb_common_bufsiz1)
#define g_flags (G.flags)
#else
#define g_flags 0
#endif
#define INIT_G() do { } while (0)
static int swap_enable_disable(char *device)
{
int status;
struct stat st;
resolve_mount_spec(&device);
xstat(device, &st);
#if ENABLE_DESKTOP
/* test for holes */
if (S_ISREG(st.st_mode))
if (st.st_blocks * (off_t)512 < st.st_size)
bb_error_msg("warning: swap file has holes");
#endif
if (applet_name[5] == 'n')
status = swapon(device, g_flags);
else
status = swapoff(device);
if (status != 0) {
bb_simple_perror_msg(device);
return 1;
}
return 0;
}
static int do_em_all(void)
{
struct mntent *m;
FILE *f;
int err;
#ifdef G
int cl_flags = g_flags;
#endif
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) {
/* swapon -a should ignore entries with noauto,
* but swapoff -a should process them */
if (applet_name[5] != 'n'
|| hasmntopt(m, MNTOPT_NOAUTO) == NULL
) {
#if ENABLE_FEATURE_SWAPON_DISCARD || ENABLE_FEATURE_SWAPON_PRI
char *p;
g_flags = cl_flags; /* each swap space might have different flags */
#if ENABLE_FEATURE_SWAPON_DISCARD
p = hasmntopt(m, "discard");
if (p) {
if (p[7] == '=') {
if (strncmp(p + 8, "once", 4) == 0 && (p[12] == ',' || p[12] == '\0'))
g_flags = (g_flags & ~SWAP_FLAG_DISCARD_MASK) | SWAP_FLAG_DISCARD | SWAP_FLAG_DISCARD_ONCE;
else if (strncmp(p + 8, "pages", 5) == 0 && (p[13] == ',' || p[13] == '\0'))
g_flags = (g_flags & ~SWAP_FLAG_DISCARD_MASK) | SWAP_FLAG_DISCARD | SWAP_FLAG_DISCARD_PAGES;
}
else if (p[7] == ',' || p[7] == '\0')
g_flags = (g_flags & ~SWAP_FLAG_DISCARD_MASK) | SWAP_FLAG_DISCARD;
}
#endif
#if ENABLE_FEATURE_SWAPON_PRI
p = hasmntopt(m, "pri");
if (p) {
/* Max allowed 32767 (== SWAP_FLAG_PRIO_MASK) */
unsigned prio = bb_strtou(p + 4, NULL, 10);
/* We want to allow "NNNN,foo", thus errno == EINVAL is allowed too */
if (errno != ERANGE) {
g_flags = (g_flags & ~SWAP_FLAG_PRIO_MASK) | SWAP_FLAG_PREFER |
MIN(prio, SWAP_FLAG_PRIO_MASK);
}
}
#endif
#endif
err += swap_enable_disable(m->mnt_fsname);
}
}
}
if (ENABLE_FEATURE_CLEAN_UP)
endmntent(f);
return err;
}
int swap_on_off_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int swap_on_off_main(int argc UNUSED_PARAM, char **argv)
{
int ret;
#if ENABLE_FEATURE_SWAPON_DISCARD
char *discard = NULL;
#endif
#if ENABLE_FEATURE_SWAPON_PRI
unsigned prio;
#endif
INIT_G();
#if !ENABLE_FEATURE_SWAPON_DISCARD && !ENABLE_FEATURE_SWAPON_PRI
ret = getopt32(argv, "a");
#else
#if ENABLE_FEATURE_SWAPON_PRI
if (applet_name[5] == 'n')
opt_complementary = "p+";
#endif
ret = getopt32(argv, (applet_name[5] == 'n') ?
#if ENABLE_FEATURE_SWAPON_DISCARD
"d::"
#endif
#if ENABLE_FEATURE_SWAPON_PRI
"p:"
#endif
"a" : "a"
#if ENABLE_FEATURE_SWAPON_DISCARD
, &discard
#endif
#if ENABLE_FEATURE_SWAPON_PRI
, &prio
#endif
);
#endif
#if ENABLE_FEATURE_SWAPON_DISCARD
if (ret & 1) { // -d
if (!discard)
g_flags |= SWAP_FLAG_DISCARD;
else if (strcmp(discard, "once") == 0)
g_flags |= SWAP_FLAG_DISCARD | SWAP_FLAG_DISCARD_ONCE;
else if (strcmp(discard, "pages") == 0)
g_flags |= SWAP_FLAG_DISCARD | SWAP_FLAG_DISCARD_PAGES;
else
bb_show_usage();
}
ret >>= 1;
#endif
#if ENABLE_FEATURE_SWAPON_PRI
if (ret & 1) // -p
g_flags |= SWAP_FLAG_PREFER |
MIN(prio, SWAP_FLAG_PRIO_MASK);
ret >>= 1;
#endif
if (ret /* & 1: not needed */) // -a
return do_em_all();
argv += optind;
if (!*argv)
bb_show_usage();
/* ret = 0; redundant */
do {
ret += swap_enable_disable(*argv);
} while (*++argv);
return ret;
}
|
