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/* Copying of files.
Copyright (C) 2001-2003, 2006-2007, 2009 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
}
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