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
|
/* sync - update the super block
Copyright (C) 1994-2015 Free Software Foundation, Inc.
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 3 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, see <http://www.gnu.org/licenses/>. */
/* Written by Jim Meyering */
#include <config.h>
#include <assert.h>
#include <getopt.h>
#include <stdio.h>
#include <sys/types.h>
#include "system.h"
#include "error.h"
#include "quote.h"
/* The official name of this program (e.g., no 'g' prefix). */
#define PROGRAM_NAME "sync"
#define AUTHORS \
proper_name ("Jim Meyering"), \
proper_name ("Giuseppe Scrivano")
#ifndef HAVE_SYNCFS
# define HAVE_SYNCFS 0
#endif
enum sync_mode
{
MODE_FILE,
MODE_DATA,
MODE_FILE_SYSTEM,
MODE_SYNC
};
static struct option const long_options[] =
{
{"data", no_argument, NULL, 'd'},
{"file-system", no_argument, NULL, 'f'},
{GETOPT_HELP_OPTION_DECL},
{GETOPT_VERSION_OPTION_DECL},
{NULL, 0, NULL, 0}
};
void
usage (int status)
{
if (status != EXIT_SUCCESS)
emit_try_help ();
else
{
printf (_("Usage: %s [OPTION] [FILE]...\n"), program_name);
fputs (_("\
Synchronize cached writes to persistent storage\n\
\n\
If one or more files are specified, sync only them,\n\
or their containing file systems.\n\
\n\
"), stdout);
fputs (_("\
-d, --data sync only file data, no unneeded metadata\n\
"), stdout);
fputs (_("\
-f, --file-system sync the file systems that contain the files\n\
"), stdout);
fputs (HELP_OPTION_DESCRIPTION, stdout);
fputs (VERSION_OPTION_DESCRIPTION, stdout);
emit_ancillary_info (PROGRAM_NAME);
}
exit (status);
}
/* Sync the specified FILE, or file systems associated with FILE.
Return 1 on success. */
static bool
sync_arg (enum sync_mode mode, char const *file)
{
bool ret = true;
int fd;
/* Note O_PATH might be supported with syncfs(),
though as of Linux 3.18 is not. */
if ((fd = open (file, O_RDONLY | O_NONBLOCK)) < 0)
{
/* Use the O_RDONLY errno, which is significant
with directories for example. */
int rd_errno = errno;
if ((fd = open (file, O_WRONLY | O_NONBLOCK)) < 0)
error (0, rd_errno, _("error opening %s"), quote (file));
return false;
}
/* We used O_NONBLOCK above to not hang with fifos,
so reset that here. */
int fdflags;
if ((fdflags = fcntl (fd, F_GETFL)) == -1
|| fcntl (fd, F_SETFL, fdflags & ~O_NONBLOCK) < 0)
{
error (0, errno, _("couldn't reset non-blocking mode %s"), quote (file));
ret = false;
}
if (ret == true)
{
int sync_status = -1;
switch (mode)
{
case MODE_DATA:
sync_status = fdatasync (fd);
break;
case MODE_FILE:
sync_status = fsync (fd);
break;
#if HAVE_SYNCFS
case MODE_FILE_SYSTEM:
sync_status = syncfs (fd);
break;
#endif
default:
assert ("invalid sync_mode");
}
if (sync_status < 0)
{
error (0, errno, _("error syncing %s"), quote (file));
ret = false;
}
}
if (close (fd) < 0)
{
error (0, errno, _("failed to close %s"), quote (file));
ret = false;
}
return ret;
}
int
main (int argc, char **argv)
{
int c;
bool args_specified;
bool arg_data = false, arg_file_system = false;
enum sync_mode mode;
bool ok = true;
initialize_main (&argc, &argv);
set_program_name (argv[0]);
setlocale (LC_ALL, "");
bindtextdomain (PACKAGE, LOCALEDIR);
textdomain (PACKAGE);
atexit (close_stdout);
while ((c = getopt_long (argc, argv, "df", long_options, NULL))
!= -1)
{
switch (c)
{
case 'd':
arg_data = true;
break;
case 'f':
arg_file_system = true;
break;
case_GETOPT_HELP_CHAR;
case_GETOPT_VERSION_CHAR (PROGRAM_NAME, AUTHORS);
default:
usage (EXIT_FAILURE);
}
}
args_specified = optind < argc;
if (arg_data && arg_file_system)
{
error (EXIT_FAILURE, 0,
_("cannot specify both --data and --file-system"));
}
if (!args_specified && arg_data)
error (EXIT_FAILURE, 0, _("--data needs at least one argument"));
if (! args_specified || (arg_file_system && ! HAVE_SYNCFS))
mode = MODE_SYNC;
else if (arg_file_system)
mode = MODE_FILE_SYSTEM;
else if (! arg_data)
mode = MODE_FILE;
else
mode = MODE_DATA;
if (mode == MODE_SYNC)
sync ();
else
{
for (; optind < argc; optind++)
ok &= sync_arg (mode, argv[optind]);
}
return ok ? EXIT_SUCCESS : EXIT_FAILURE;
}
|
