1 /* Update a tar archive.
3 Copyright (C) 1988, 1992, 1994, 1996, 1997, 1999, 2000, 2001, 2003,
4 2004, 2005, 2007, 2010 Free Software Foundation, Inc.
6 This program is free software; you can redistribute it and/or modify it
7 under the terms of the GNU General Public License as published by the
8 Free Software Foundation; either version 3, or (at your option) any later
11 This program is distributed in the hope that it will be useful, but
12 WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
14 Public License for more details.
16 You should have received a copy of the GNU General Public License along
17 with this program; if not, write to the Free Software Foundation, Inc.,
18 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
20 /* Implement the 'r', 'u' and 'A' options for tar. 'A' means that the
21 file names are tar files, and they should simply be appended to the end
22 of the archive. No attempt is made to record the reads from the args; if
23 they're on raw tape or something like that, it'll probably lose... */
29 /* FIXME: This module should not directly handle the following variable,
30 instead, this should be done in buffer.c only. */
31 extern union block
*current_block
;
33 /* We've hit the end of the old stuff, and its time to start writing new
34 stuff to the tape. This involves seeking back one record and
35 re-writing the current record (which has been changed).
36 FIXME: Either eliminate it or move it to common.h.
38 bool time_to_start_writing
;
40 /* Pointer to where we started to write in the first record we write out.
41 This is used if we can't backspace the output and have to null out the
42 first part of the record. */
45 /* Catenate file FILE_NAME to the archive without creating a header for it.
46 It had better be a tar file or the archive is screwed. */
48 append_file (char *file_name
)
50 int handle
= openat (chdir_fd
, file_name
, O_RDONLY
| O_BINARY
);
51 struct stat stat_data
;
55 open_error (file_name
);
59 if (fstat (handle
, &stat_data
) != 0)
60 stat_error (file_name
);
63 off_t bytes_left
= stat_data
.st_size
;
65 while (bytes_left
> 0)
67 union block
*start
= find_next_block ();
68 size_t buffer_size
= available_space_after (start
);
70 char buf
[UINTMAX_STRSIZE_BOUND
];
72 if (bytes_left
< buffer_size
)
74 buffer_size
= bytes_left
;
75 status
= buffer_size
% BLOCKSIZE
;
77 memset (start
->buffer
+ bytes_left
, 0, BLOCKSIZE
- status
);
80 status
= safe_read (handle
, start
->buffer
, buffer_size
);
81 if (status
== SAFE_READ_ERROR
)
82 read_fatal_details (file_name
, stat_data
.st_size
- bytes_left
,
86 ngettext ("%s: File shrank by %s byte",
87 "%s: File shrank by %s bytes",
89 quotearg_colon (file_name
),
90 STRINGIFY_BIGINT (bytes_left
, buf
)));
94 set_next_block_after (start
+ (status
- 1) / BLOCKSIZE
);
98 if (close (handle
) != 0)
99 close_error (file_name
);
102 /* Implement the 'r' (add files to end of archive), and 'u' (add files
103 to end of archive if they aren't there, or are more up to date than
104 the version in the archive) commands. */
106 update_archive (void)
108 enum read_header previous_status
= HEADER_STILL_UNREAD
;
109 bool found_end
= false;
112 open_archive (ACCESS_UPDATE
);
113 buffer_write_global_xheader ();
117 enum read_header status
= read_header (¤t_header
,
123 case HEADER_STILL_UNREAD
:
124 case HEADER_SUCCESS_EXTENDED
:
131 decode_header (current_header
, ¤t_stat_info
,
133 archive_format
= current_format
;
135 if (subcommand_option
== UPDATE_SUBCOMMAND
136 && (name
= name_scan (current_stat_info
.file_name
)) != NULL
)
140 chdir_do (name
->change_dir
);
141 if (deref_stat (current_stat_info
.file_name
, &s
) == 0)
143 if (S_ISDIR (s
.st_mode
))
147 int fd
= openat (chdir_fd
, name
->name
,
148 open_read_flags
| O_DIRECTORY
);
150 open_error (name
->name
);
151 else if (! ((stream
= fdopendir (fd
))
152 && (dirp
= streamsavedir (stream
))))
153 savedir_error (name
->name
);
156 namebuf_t nbuf
= namebuf_create (name
->name
);
158 for (p
= dirp
; *p
; p
+= strlen (p
) + 1)
159 addname (namebuf_name (nbuf
, p
),
169 ? closedir (stream
) != 0
170 : 0 <= fd
&& close (fd
) != 0)
171 savedir_error (name
->name
);
173 else if (tar_timespec_cmp (get_stat_mtime (&s
),
174 current_stat_info
.mtime
)
184 case HEADER_ZERO_BLOCK
:
185 current_block
= current_header
;
189 case HEADER_END_OF_FILE
:
194 set_next_block_after (current_header
);
195 switch (previous_status
)
197 case HEADER_STILL_UNREAD
:
198 WARN ((0, 0, _("This does not look like a tar archive")));
202 case HEADER_ZERO_BLOCK
:
203 ERROR ((0, 0, _("Skipping to next header")));
209 case HEADER_END_OF_FILE
:
210 case HEADER_SUCCESS_EXTENDED
:
216 tar_stat_destroy (¤t_stat_info
);
217 previous_status
= status
;
221 time_to_start_writing
= true;
222 output_start
= current_block
->buffer
;
225 struct name
const *p
;
226 while ((p
= name_from_list ()) != NULL
)
228 char *file_name
= p
->name
;
229 if (excluded_name (file_name
))
231 if (interactive_option
&& !confirm ("add", file_name
))
233 if (subcommand_option
== CAT_SUBCOMMAND
)
234 append_file (file_name
);
236 dump_file (0, file_name
, file_name
);
242 finish_deferred_unlinks ();