--- /dev/null
+/* Copying of files.
+ Copyright (C) 2001-2003 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 2, 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, write to the Free Software Foundation,
+ Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
+
+
+#ifdef HAVE_CONFIG_H
+# include "config.h"
+#endif
+
+/* Specification. */
+#include "copy-file.h"
+
+#include <errno.h>
+#include <fcntl.h>
+#include <sys/stat.h>
+
+#ifdef HAVE_UNISTD_H
+# include <unistd.h>
+#endif
+
+#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 "binary-io.h"
+#include "exit.h"
+#include "gettext.h"
+
+#define _(str) gettext (str)
+
+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[4096];
+ const int buf_size = sizeof (buf);
+
+ 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, buf_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);
+ }
+
+ 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);
+
+ /* 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
+
+ /* Preserve the owner and group. */
+ chown (dest_filename, statbuf.st_uid, statbuf.st_gid);
+
+ /* Preserve the access permissions. */
+ chmod (dest_filename, mode);
+}
--- /dev/null
+/* Copying of files.
+ Copyright (C) 2001-2003 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 2, 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, write to the Free Software Foundation,
+ Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
+
+/* Copy a regular file: from src_filename to dest_filename.
+ The destination file is assumed to be a backup file.
+ Modification times, owner, group and access permissions are preserved as
+ far as possible.
+ Exit upon failure. */
+extern void copy_file_preserving (const char *src_filename, const char *dest_filename);
--- /dev/null
+# copy-file.m4 serial 1
+dnl Copyright (C) 2003 Free Software Foundation, Inc.
+dnl This file is free software, distributed under the terms of the GNU
+dnl General Public License. As a special exception to the GNU General
+dnl Public License, this file may be distributed as part of a program
+dnl that contains a configuration script generated by Autoconf, under
+dnl the same distribution terms as the rest of that program.
+
+AC_DEFUN([gl_COPY_FILE],
+[
+ AC_CHECK_HEADERS_ONCE(unistd.h utime.h)
+ AC_CHECK_FUNCS(utime utimes)
+])