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
|
/* Copying of files.
Copyright (C) 2001-2003, 2006-2007, 2009-2010 Free Software Foundation, Inc.
Written by Bruno Haible <haible@clisp.cons.org>, 2001.
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/>. */
#include <config.h>
/* Specification. */
#include "copy-file.h"
#include <errno.h>
#include <fcntl.h>
#include <stddef.h>
#include <stdlib.h>
#include <sys/stat.h>
#include <unistd.h>
#if HAVE_UTIME || HAVE_UTIMES
# if HAVE_UTIME_H
# include <utime.h>
# else
# include <sys/utime.h>
# endif
#endif
#include "error.h"
#include "safe-read.h"
#include "full-write.h"
#include "acl.h"
#include "binary-io.h"
#include "gettext.h"
#include "xalloc.h"
#define _(str) gettext (str)
/* The results of open() in this file are not used with fchdir,
therefore save some unnecessary work in fchdir.c. */
#undef open
#undef close
enum { IO_SIZE = 32 * 1024 };
void
copy_file_preserving (const char *src_filename, const char *dest_filename)
{
int src_fd;
struct stat statbuf;
int mode;
int dest_fd;
char *buf = xmalloc (IO_SIZE);
src_fd = open (src_filename, O_RDONLY | O_BINARY);
if (src_fd < 0 || fstat (src_fd, &statbuf) < 0)
error (EXIT_FAILURE, errno, _("error while opening \"%s\" for reading"),
src_filename);
mode = statbuf.st_mode & 07777;
dest_fd = open (dest_filename, O_WRONLY | O_CREAT | O_TRUNC | O_BINARY, 0600);
if (dest_fd < 0)
error (EXIT_FAILURE, errno, _("cannot open backup file \"%s\" for writing"),
dest_filename);
/* Copy the file contents. */
for (;;)
{
size_t n_read = safe_read (src_fd, buf, IO_SIZE);
if (n_read == SAFE_READ_ERROR)
error (EXIT_FAILURE, errno, _("error reading \"%s\""), src_filename);
if (n_read == 0)
break;
if (full_write (dest_fd, buf, n_read) < n_read)
error (EXIT_FAILURE, errno, _("error writing \"%s\""), dest_filename);
}
free (buf);
#if !USE_ACL
if (close (dest_fd) < 0)
error (EXIT_FAILURE, errno, _("error writing \"%s\""), dest_filename);
if (close (src_fd) < 0)
error (EXIT_FAILURE, errno, _("error after reading \"%s\""), src_filename);
#endif
/* Preserve the access and modification times. */
#if HAVE_UTIME
{
struct utimbuf ut;
ut.actime = statbuf.st_atime;
ut.modtime = statbuf.st_mtime;
utime (dest_filename, &ut);
}
#elif HAVE_UTIMES
{
struct timeval ut[2];
ut[0].tv_sec = statbuf.st_atime; ut[0].tv_usec = 0;
ut[1].tv_sec = statbuf.st_mtime; ut[1].tv_usec = 0;
utimes (dest_filename, &ut);
}
#endif
#if HAVE_CHOWN
/* Preserve the owner and group. */
chown (dest_filename, statbuf.st_uid, statbuf.st_gid);
#endif
/* Preserve the access permissions. */
#if USE_ACL
if (copy_acl (src_filename, src_fd, dest_filename, dest_fd, mode))
exit (EXIT_FAILURE);
#else
chmod (dest_filename, mode);
#endif
#if USE_ACL
if (close (dest_fd) < 0)
error (EXIT_FAILURE, errno, _("error writing \"%s\""), dest_filename);
if (close (src_fd) < 0)
error (EXIT_FAILURE, errno, _("error after reading \"%s\""), src_filename);
#endif
}
|
