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 (dereference_option
,
142 current_stat_info
.file_name
, &s
) == 0)
144 if (S_ISDIR (s
.st_mode
))
148 int fd
= openat (chdir_fd
, name
->name
,
149 open_read_flags
| O_DIRECTORY
);
151 open_error (name
->name
);
152 else if (! ((stream
= fdopendir (fd
))
153 && (dirp
= streamsavedir (stream
))))
154 savedir_error (name
->name
);
157 namebuf_t nbuf
= namebuf_create (name
->name
);
159 for (p
= dirp
; *p
; p
+= strlen (p
) + 1)
160 addname (namebuf_name (nbuf
, p
),
170 ? closedir (stream
) != 0
171 : 0 <= fd
&& close (fd
) != 0)
172 savedir_error (name
->name
);
174 else if (tar_timespec_cmp (get_stat_mtime (&s
),
175 current_stat_info
.mtime
)
185 case HEADER_ZERO_BLOCK
:
186 current_block
= current_header
;
190 case HEADER_END_OF_FILE
:
195 set_next_block_after (current_header
);
196 switch (previous_status
)
198 case HEADER_STILL_UNREAD
:
199 WARN ((0, 0, _("This does not look like a tar archive")));
203 case HEADER_ZERO_BLOCK
:
204 ERROR ((0, 0, _("Skipping to next header")));
210 case HEADER_END_OF_FILE
:
211 case HEADER_SUCCESS_EXTENDED
:
217 tar_stat_destroy (¤t_stat_info
);
218 previous_status
= status
;
222 time_to_start_writing
= true;
223 output_start
= current_block
->buffer
;
226 struct name
const *p
;
227 while ((p
= name_from_list ()) != NULL
)
229 char *file_name
= p
->name
;
230 if (excluded_name (file_name
))
232 if (interactive_option
&& !confirm ("add", file_name
))
234 if (subcommand_option
== CAT_SUBCOMMAND
)
235 append_file (file_name
);
237 dump_file (0, file_name
, file_name
);
243 finish_deferred_unlinks ();