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1/* vi: set sw=4 ts=4: */
2/*
3 * Mini cpio implementation for busybox
4 *
5 * Copyright (C) 2001 by Glenn McGrath
6 *
7 * Licensed under GPLv2 or later, see file LICENSE in this source tree.
8 *
9 * Limitations:
10 * Doesn't check CRC's
11 * Only supports new ASCII and CRC formats
12 */
13#include "libbb.h"
14#include "bb_archive.h"
15
16//config:config CPIO
17//config: bool "cpio"
18//config: default y
19//config: help
20//config: cpio is an archival utility program used to create, modify, and
21//config: extract contents from archives.
22//config: cpio has 110 bytes of overheads for every stored file.
23//config:
24//config: This implementation of cpio can extract cpio archives created in the
25//config: "newc" or "crc" format, it cannot create or modify them.
26//config:
27//config: Unless you have a specific application which requires cpio, you
28//config: should probably say N here.
29//config:
30//config:config FEATURE_CPIO_O
31//config: bool "Support for archive creation"
32//config: default y
33//config: depends on CPIO
34//config: help
35//config: This implementation of cpio can create cpio archives in the "newc"
36//config: format only.
37//config:
38//config:config FEATURE_CPIO_P
39//config: bool "Support for passthrough mode"
40//config: default y
41//config: depends on FEATURE_CPIO_O
42//config: help
43//config: Passthrough mode. Rarely used.
44
45//applet:IF_CPIO(APPLET(cpio, BB_DIR_BIN, BB_SUID_DROP))
46//kbuild:lib-$(CONFIG_CPIO) += cpio.o
47
48//usage:#define cpio_trivial_usage
49//usage: "[-dmvu] [-F FILE]" IF_FEATURE_CPIO_O(" [-H newc]")
50//usage: " [-ti"IF_FEATURE_CPIO_O("o")"]" IF_FEATURE_CPIO_P(" [-p DIR]")
51//usage: " [EXTR_FILE]..."
52//usage:#define cpio_full_usage "\n\n"
53//usage: "Extract or list files from a cpio archive"
54//usage: IF_FEATURE_CPIO_O(", or"
55//usage: "\ncreate an archive" IF_FEATURE_CPIO_P(" (-o) or copy files (-p)")
56//usage: " using file list on stdin"
57//usage: )
58//usage: "\n"
59//usage: "\nMain operation mode:"
60//usage: "\n -t List"
61//usage: "\n -i Extract EXTR_FILEs (or all)"
62//usage: IF_FEATURE_CPIO_O(
63//usage: "\n -o Create (requires -H newc)"
64//usage: )
65//usage: IF_FEATURE_CPIO_P(
66//usage: "\n -p DIR Copy files to DIR"
67//usage: )
68//usage: "\n -d Make leading directories"
69//usage: "\n -m Preserve mtime"
70//usage: "\n -v Verbose"
71//usage: "\n -u Overwrite"
72//usage: "\n -F FILE Input (-t,-i,-p) or output (-o) file"
73//usage: IF_FEATURE_CPIO_O(
74//usage: "\n -H newc Archive format"
75//usage: )
76
77/* GNU cpio 2.9 --help (abridged):
78
79 Modes:
80 -t, --list List the archive
81 -i, --extract Extract files from an archive
82 -o, --create Create the archive
83 -p, --pass-through Copy-pass mode
84
85 Options valid in any mode:
86 --block-size=SIZE I/O block size = SIZE * 512 bytes
87 -B I/O block size = 5120 bytes
88 -c Use the old portable (ASCII) archive format
89 -C, --io-size=NUMBER I/O block size in bytes
90 -f, --nonmatching Only copy files that do not match given pattern
91 -F, --file=FILE Use FILE instead of standard input or output
92 -H, --format=FORMAT Use given archive FORMAT
93 -M, --message=STRING Print STRING when the end of a volume of the
94 backup media is reached
95 -n, --numeric-uid-gid If -v, show numeric UID and GID
96 --quiet Do not print the number of blocks copied
97 --rsh-command=COMMAND Use remote COMMAND instead of rsh
98 -v, --verbose Verbosely list the files processed
99 -V, --dot Print a "." for each file processed
100 -W, --warning=FLAG Control warning display: 'none','truncate','all';
101 multiple options accumulate
102
103 Options valid only in --extract mode:
104 -b, --swap Swap both halfwords of words and bytes of
105 halfwords in the data (equivalent to -sS)
106 -r, --rename Interactively rename files
107 -s, --swap-bytes Swap the bytes of each halfword in the files
108 -S, --swap-halfwords Swap the halfwords of each word (4 bytes)
109 --to-stdout Extract files to standard output
110 -E, --pattern-file=FILE Read additional patterns specifying filenames to
111 extract or list from FILE
112 --only-verify-crc Verify CRC's, don't actually extract the files
113
114 Options valid only in --create mode:
115 -A, --append Append to an existing archive
116 -O FILE File to use instead of standard output
117
118 Options valid only in --pass-through mode:
119 -l, --link Link files instead of copying them, when possible
120
121 Options valid in --extract and --create modes:
122 --absolute-filenames Do not strip file system prefix components from
123 the file names
124 --no-absolute-filenames Create all files relative to the current dir
125
126 Options valid in --create and --pass-through modes:
127 -0, --null A list of filenames is terminated by a NUL
128 -a, --reset-access-time Reset the access times of files after reading them
129 -I FILE File to use instead of standard input
130 -L, --dereference Dereference symbolic links (copy the files
131 that they point to instead of copying the links)
132 -R, --owner=[USER][:.][GROUP] Set owner of created files
133
134 Options valid in --extract and --pass-through modes:
135 -d, --make-directories Create leading directories where needed
136 -m, --preserve-modification-time Retain mtime when creating files
137 --no-preserve-owner Do not change the ownership of the files
138 --sparse Write files with blocks of zeros as sparse files
139 -u, --unconditional Replace all files unconditionally
140 */
141
142enum {
143 OPT_EXTRACT = (1 << 0),
144 OPT_TEST = (1 << 1),
145 OPT_NUL_TERMINATED = (1 << 2),
146 OPT_UNCONDITIONAL = (1 << 3),
147 OPT_VERBOSE = (1 << 4),
148 OPT_CREATE_LEADING_DIR = (1 << 5),
149 OPT_PRESERVE_MTIME = (1 << 6),
150 OPT_DEREF = (1 << 7),
151 OPT_FILE = (1 << 8),
152 OPTBIT_FILE = 8,
153 IF_FEATURE_CPIO_O(OPTBIT_CREATE ,)
154 IF_FEATURE_CPIO_O(OPTBIT_FORMAT ,)
155 IF_FEATURE_CPIO_P(OPTBIT_PASSTHROUGH,)
156 IF_LONG_OPTS( OPTBIT_QUIET ,)
157 IF_LONG_OPTS( OPTBIT_2STDOUT ,)
158 OPT_CREATE = IF_FEATURE_CPIO_O((1 << OPTBIT_CREATE )) + 0,
159 OPT_FORMAT = IF_FEATURE_CPIO_O((1 << OPTBIT_FORMAT )) + 0,
160 OPT_PASSTHROUGH = IF_FEATURE_CPIO_P((1 << OPTBIT_PASSTHROUGH)) + 0,
161 OPT_QUIET = IF_LONG_OPTS( (1 << OPTBIT_QUIET )) + 0,
162 OPT_2STDOUT = IF_LONG_OPTS( (1 << OPTBIT_2STDOUT )) + 0,
163};
164
165#define OPTION_STR "it0uvdmLF:"
166
167#if ENABLE_FEATURE_CPIO_O
168static off_t cpio_pad4(off_t size)
169{
170 int i;
171
172 i = (- size) & 3;
173 size += i;
174 while (--i >= 0)
175 bb_putchar('\0');
176 return size;
177}
178
179/* Return value will become exit code.
180 * It's ok to exit instead of return. */
181static NOINLINE int cpio_o(void)
182{
183 static const char trailer[] ALIGN1 = "TRAILER!!!";
184 struct name_s {
185 struct name_s *next;
186 char name[1];
187 };
188 struct inodes_s {
189 struct inodes_s *next;
190 struct name_s *names;
191 struct stat st;
192 };
193
194 struct inodes_s *links = NULL;
195 off_t bytes = 0; /* output bytes count */
196
197 while (1) {
198 const char *name;
199 char *line;
200 struct stat st;
201
202 line = (option_mask32 & OPT_NUL_TERMINATED)
203 ? bb_get_chunk_from_file(stdin, NULL)
204 : xmalloc_fgetline(stdin);
205
206 if (line) {
207 /* Strip leading "./[./]..." from the filename */
208 name = line;
209 while (name[0] == '.' && name[1] == '/') {
210 while (*++name == '/')
211 continue;
212 }
213 if (!*name) { /* line is empty */
214 free(line);
215 continue;
216 }
217 if ((option_mask32 & OPT_DEREF)
218 ? stat(name, &st)
219 : lstat(name, &st)
220 ) {
221 abort_cpio_o:
222 bb_simple_perror_msg_and_die(name);
223 }
224
225 if (!(S_ISLNK(st.st_mode) || S_ISREG(st.st_mode)))
226 st.st_size = 0; /* paranoia */
227
228 /* Store hardlinks for later processing, dont output them */
229 if (!S_ISDIR(st.st_mode) && st.st_nlink > 1) {
230 struct name_s *n;
231 struct inodes_s *l;
232
233 /* Do we have this hardlink remembered? */
234 l = links;
235 while (1) {
236 if (l == NULL) {
237 /* Not found: add new item to "links" list */
238 l = xzalloc(sizeof(*l));
239 l->st = st;
240 l->next = links;
241 links = l;
242 break;
243 }
244 if (l->st.st_ino == st.st_ino) {
245 /* found */
246 break;
247 }
248 l = l->next;
249 }
250 /* Add new name to "l->names" list */
251 n = xmalloc(sizeof(*n) + strlen(name));
252 strcpy(n->name, name);
253 n->next = l->names;
254 l->names = n;
255
256 free(line);
257 continue;
258 }
259
260 } else { /* line == NULL: EOF */
261 next_link:
262 if (links) {
263 /* Output hardlink's data */
264 st = links->st;
265 name = links->names->name;
266 links->names = links->names->next;
267 /* GNU cpio is reported to emit file data
268 * only for the last instance. Mimic that. */
269 if (links->names == NULL)
270 links = links->next;
271 else
272 st.st_size = 0;
273 /* NB: we leak links->names and/or links,
274 * this is intended (we exit soon anyway) */
275 } else {
276 /* If no (more) hardlinks to output,
277 * output "trailer" entry */
278 name = trailer;
279 /* st.st_size == 0 is a must, but for uniformity
280 * in the output, we zero out everything */
281 memset(&st, 0, sizeof(st));
282 /* st.st_nlink = 1; - GNU cpio does this */
283 }
284 }
285
286 bytes += printf("070701"
287 "%08X%08X%08X%08X%08X%08X%08X"
288 "%08X%08X%08X%08X" /* GNU cpio uses uppercase hex */
289 /* strlen+1: */ "%08X"
290 /* chksum: */ "00000000" /* (only for "070702" files) */
291 /* name,NUL: */ "%s%c",
292 (unsigned)(uint32_t) st.st_ino,
293 (unsigned)(uint32_t) st.st_mode,
294 (unsigned)(uint32_t) st.st_uid,
295 (unsigned)(uint32_t) st.st_gid,
296 (unsigned)(uint32_t) st.st_nlink,
297 (unsigned)(uint32_t) st.st_mtime,
298 (unsigned)(uint32_t) st.st_size,
299 (unsigned)(uint32_t) major(st.st_dev),
300 (unsigned)(uint32_t) minor(st.st_dev),
301 (unsigned)(uint32_t) major(st.st_rdev),
302 (unsigned)(uint32_t) minor(st.st_rdev),
303 (unsigned)(strlen(name) + 1),
304 name, '\0');
305 bytes = cpio_pad4(bytes);
306
307 if (st.st_size) {
308 if (S_ISLNK(st.st_mode)) {
309 char *lpath = xmalloc_readlink_or_warn(name);
310 if (!lpath)
311 goto abort_cpio_o;
312 bytes += printf("%s", lpath);
313 free(lpath);
314 } else { /* S_ISREG */
315 int fd = xopen(name, O_RDONLY);
316 fflush_all();
317 /* We must abort if file got shorter too! */
318 bb_copyfd_exact_size(fd, STDOUT_FILENO, st.st_size);
319 bytes += st.st_size;
320 close(fd);
321 }
322 bytes = cpio_pad4(bytes);
323 }
324
325 if (!line) {
326 if (name != trailer)
327 goto next_link;
328 /* TODO: GNU cpio pads trailer to 512 bytes, do we want that? */
329 return EXIT_SUCCESS;
330 }
331
332 free(line);
333 } /* end of "while (1)" */
334}
335#endif
336
337int cpio_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
338int cpio_main(int argc UNUSED_PARAM, char **argv)
339{
340 archive_handle_t *archive_handle;
341 char *cpio_filename;
342 IF_FEATURE_CPIO_O(const char *cpio_fmt = "";)
343 unsigned opt;
344
345#if ENABLE_LONG_OPTS
346 applet_long_options =
347 "extract\0" No_argument "i"
348 "list\0" No_argument "t"
349#if ENABLE_FEATURE_CPIO_O
350 "create\0" No_argument "o"
351 "format\0" Required_argument "H"
352#if ENABLE_FEATURE_CPIO_P
353 "pass-through\0" No_argument "p"
354#endif
355#endif
356 "verbose\0" No_argument "v"
357 "quiet\0" No_argument "\xff"
358 "to-stdout\0" No_argument "\xfe"
359 ;
360#endif
361
362 archive_handle = init_handle();
363 /* archive_handle->src_fd = STDIN_FILENO; - done by init_handle */
364 archive_handle->ah_flags = ARCHIVE_EXTRACT_NEWER;
365
366 /* As of now we do not enforce this: */
367 /* -i,-t,-o,-p are mutually exclusive */
368 /* -u,-d,-m make sense only with -i or -p */
369 /* -L makes sense only with -o or -p */
370
371#if !ENABLE_FEATURE_CPIO_O
372 opt = getopt32(argv, OPTION_STR, &cpio_filename);
373 argv += optind;
374 if (opt & OPT_FILE) { /* -F */
375 xmove_fd(xopen(cpio_filename, O_RDONLY), STDIN_FILENO);
376 }
377#else
378 opt = getopt32(argv, OPTION_STR "oH:" IF_FEATURE_CPIO_P("p"), &cpio_filename, &cpio_fmt);
379 argv += optind;
380 if ((opt & (OPT_FILE|OPT_CREATE)) == OPT_FILE) { /* -F without -o */
381 xmove_fd(xopen(cpio_filename, O_RDONLY), STDIN_FILENO);
382 }
383 if (opt & OPT_PASSTHROUGH) {
384 pid_t pid;
385 struct fd_pair pp;
386
387 if (argv[0] == NULL)
388 bb_show_usage();
389 if (opt & OPT_CREATE_LEADING_DIR)
390 mkdir(argv[0], 0777);
391 /* Crude existence check:
392 * close(xopen(argv[0], O_RDONLY | O_DIRECTORY));
393 * We can also xopen, fstat, IS_DIR, later fchdir.
394 * This would check for existence earlier and cleaner.
395 * As it stands now, if we fail xchdir later,
396 * child dies on EPIPE, unless it caught
397 * a diffrerent problem earlier.
398 * This is good enough for now.
399 */
400#if !BB_MMU
401 pp.rd = 3;
402 pp.wr = 4;
403 if (!re_execed) {
404 close(3);
405 close(4);
406 xpiped_pair(pp);
407 }
408#else
409 xpiped_pair(pp);
410#endif
411 pid = fork_or_rexec(argv - optind);
412 if (pid == 0) { /* child */
413 close(pp.rd);
414 xmove_fd(pp.wr, STDOUT_FILENO);
415 goto dump;
416 }
417 /* parent */
418 USE_FOR_NOMMU(argv[-optind][0] &= 0x7f); /* undo fork_or_rexec() damage */
419 xchdir(*argv++);
420 close(pp.wr);
421 xmove_fd(pp.rd, STDIN_FILENO);
422 //opt &= ~OPT_PASSTHROUGH;
423 opt |= OPT_EXTRACT;
424 goto skip;
425 }
426 /* -o */
427 if (opt & OPT_CREATE) {
428 if (cpio_fmt[0] != 'n') /* we _require_ "-H newc" */
429 bb_show_usage();
430 if (opt & OPT_FILE) {
431 xmove_fd(xopen(cpio_filename, O_WRONLY | O_CREAT | O_TRUNC), STDOUT_FILENO);
432 }
433 dump:
434 return cpio_o();
435 }
436 skip:
437#endif
438
439 /* One of either extract or test options must be given */
440 if ((opt & (OPT_TEST | OPT_EXTRACT)) == 0) {
441 bb_show_usage();
442 }
443
444 if (opt & OPT_TEST) {
445 /* if both extract and test options are given, ignore extract option */
446 opt &= ~OPT_EXTRACT;
447 archive_handle->action_header = header_list;
448 }
449 if (opt & OPT_EXTRACT) {
450 archive_handle->action_data = data_extract_all;
451 if (opt & OPT_2STDOUT)
452 archive_handle->action_data = data_extract_to_stdout;
453 }
454 if (opt & OPT_UNCONDITIONAL) {
455 archive_handle->ah_flags |= ARCHIVE_UNLINK_OLD;
456 archive_handle->ah_flags &= ~ARCHIVE_EXTRACT_NEWER;
457 }
458 if (opt & OPT_VERBOSE) {
459 if (archive_handle->action_header == header_list) {
460 archive_handle->action_header = header_verbose_list;
461 } else {
462 archive_handle->action_header = header_list;
463 }
464 }
465 if (opt & OPT_CREATE_LEADING_DIR) {
466 archive_handle->ah_flags |= ARCHIVE_CREATE_LEADING_DIRS;
467 }
468 if (opt & OPT_PRESERVE_MTIME) {
469 archive_handle->ah_flags |= ARCHIVE_RESTORE_DATE;
470 }
471
472 while (*argv) {
473 archive_handle->filter = filter_accept_list;
474 llist_add_to(&archive_handle->accept, *argv);
475 argv++;
476 }
477
478 /* see get_header_cpio */
479 archive_handle->cpio__blocks = (off_t)-1;
480 while (get_header_cpio(archive_handle) == EXIT_SUCCESS)
481 continue;
482
483 if ((off_t)archive_handle->cpio__blocks != (off_t)-1
484 && !(opt & OPT_QUIET)
485 ) {
486 fprintf(stderr, "%"OFF_FMT"u blocks\n", archive_handle->cpio__blocks);
487 }
488
489 return EXIT_SUCCESS;
490}
491
generated by cgit at 2024-05-15 08:37:53 (GMT)