1/*-
2 * This file is in the public domain.
3 * Do with it as you will.
4 */
5
6/*-
7 * This is a compact "tar" program whose primary goal is small size.
8 * Statically linked, it can be very small indeed.  This serves a number
9 * of goals:
10 *   o a testbed for libarchive (to check for link pollution),
11 *   o a useful tool for space-constrained systems (boot floppies, etc),
12 *   o a place to experiment with new implementation ideas for bsdtar,
13 *   o a small program to demonstrate libarchive usage.
14 *
15 * Use the following macros to suppress features:
16 *   NO_BZIP2 - Implies NO_BZIP2_CREATE and NO_BZIP2_EXTRACT
17 *   NO_BZIP2_CREATE - Suppress bzip2 compression support.
18 *   NO_BZIP2_EXTRACT - Suppress bzip2 auto-detection and decompression.
19 *   NO_COMPRESS - Implies NO_COMPRESS_CREATE and NO_COMPRESS_EXTRACT
20 *   NO_COMPRESS_CREATE - Suppress compress(1) compression support
21 *   NO_COMPRESS_EXTRACT - Suppress compress(1) auto-detect and decompression.
22 *   NO_CREATE - Suppress all archive creation support.
23 *   NO_CPIO_EXTRACT - Suppress auto-detect and dearchiving of cpio archives.
24 *   NO_GZIP - Implies NO_GZIP_CREATE and NO_GZIP_EXTRACT
25 *   NO_GZIP_CREATE - Suppress gzip compression support.
26 *   NO_GZIP_EXTRACT - Suppress gzip auto-detection and decompression.
27 *   NO_LOOKUP - Try to avoid getpw/getgr routines, which can be very large
28 *   NO_TAR_EXTRACT - Suppress tar extraction
29 *
30 * With all of the above macros defined (except NO_TAR_EXTRACT), you
31 * get a very small program that can recognize and extract essentially
32 * any uncompressed tar archive.  On FreeBSD 5.1, this minimal program
33 * is under 64k, statically linked, which compares rather favorably to
34 *         main(){printf("hello, world");}
35 * which is over 60k statically linked on the same operating system.
36 * Without any of the above macros, you get a static executable of
37 * about 180k with a lot of very sophisticated modern features.
38 * Obviously, it's trivial to add support for ISO, Zip, mtree,
39 * lzma/xz, etc.  Just fill in the appropriate setup calls.
40 */
41
42#include <sys/types.h>
43__FBSDID("$FreeBSD$");
44
45#include <sys/stat.h>
46
47#include <archive.h>
48#include <archive_entry.h>
49#include <fcntl.h>
50#include <stdio.h>
51#include <stdlib.h>
52#include <string.h>
53#include <unistd.h>
54
55#ifndef NO_CREATE
56#include "tree.h"
57#endif
58
59/*
60 * NO_CREATE implies NO_BZIP2_CREATE and NO_GZIP_CREATE and NO_COMPRESS_CREATE.
61 */
62#ifdef NO_CREATE
63#undef NO_BZIP2_CREATE
64#define NO_BZIP2_CREATE
65#undef NO_COMPRESS_CREATE
66#define	NO_COMPRESS_CREATE
67#undef NO_GZIP_CREATE
68#define NO_GZIP_CREATE
69#endif
70
71/*
72 * The combination of NO_BZIP2_CREATE and NO_BZIP2_EXTRACT is
73 * equivalent to NO_BZIP2.
74 */
75#ifdef NO_BZIP2_CREATE
76#ifdef NO_BZIP2_EXTRACT
77#undef NO_BZIP2
78#define NO_BZIP2
79#endif
80#endif
81
82#ifdef NO_BZIP2
83#undef NO_BZIP2_EXTRACT
84#define NO_BZIP2_EXTRACT
85#undef NO_BZIP2_CREATE
86#define NO_BZIP2_CREATE
87#endif
88
89/*
90 * The combination of NO_COMPRESS_CREATE and NO_COMPRESS_EXTRACT is
91 * equivalent to NO_COMPRESS.
92 */
93#ifdef NO_COMPRESS_CREATE
94#ifdef NO_COMPRESS_EXTRACT
95#undef NO_COMPRESS
96#define NO_COMPRESS
97#endif
98#endif
99
100#ifdef NO_COMPRESS
101#undef NO_COMPRESS_EXTRACT
102#define NO_COMPRESS_EXTRACT
103#undef NO_COMPRESS_CREATE
104#define NO_COMPRESS_CREATE
105#endif
106
107/*
108 * The combination of NO_GZIP_CREATE and NO_GZIP_EXTRACT is
109 * equivalent to NO_GZIP.
110 */
111#ifdef NO_GZIP_CREATE
112#ifdef NO_GZIP_EXTRACT
113#undef NO_GZIP
114#define NO_GZIP
115#endif
116#endif
117
118#ifdef NO_GZIP
119#undef NO_GZIP_EXTRACT
120#define NO_GZIP_EXTRACT
121#undef NO_GZIP_CREATE
122#define NO_GZIP_CREATE
123#endif
124
125#ifndef NO_CREATE
126static void	create(const char *filename, int compress, const char **argv);
127#endif
128static void	errmsg(const char *);
129static void	extract(const char *filename, int do_extract, int flags);
130static int	copy_data(struct archive *, struct archive *);
131static void	msg(const char *);
132static void	usage(void);
133
134static int verbose = 0;
135
136int
137main(int argc, const char **argv)
138{
139	const char *filename = NULL;
140	int compress, flags, mode, opt;
141
142	(void)argc;
143	mode = 'x';
144	verbose = 0;
145	compress = '\0';
146	flags = ARCHIVE_EXTRACT_TIME;
147
148	/* Among other sins, getopt(3) pulls in printf(3). */
149	while (*++argv != NULL && **argv == '-') {
150		const char *p = *argv + 1;
151
152		while ((opt = *p++) != '\0') {
153			switch (opt) {
154#ifndef NO_CREATE
155			case 'c':
156				mode = opt;
157				break;
158#endif
159			case 'f':
160				if (*p != '\0')
161					filename = p;
162				else
163					filename = *++argv;
164				p += strlen(p);
165				break;
166#ifndef NO_BZIP2_CREATE
167			case 'j':
168				compress = opt;
169				break;
170#endif
171			case 'p':
172				flags |= ARCHIVE_EXTRACT_PERM;
173				flags |= ARCHIVE_EXTRACT_ACL;
174				flags |= ARCHIVE_EXTRACT_FFLAGS;
175				break;
176			case 't':
177				mode = opt;
178				break;
179			case 'v':
180				verbose++;
181				break;
182			case 'x':
183				mode = opt;
184				break;
185#ifndef NO_BZIP2_CREATE
186			case 'y':
187				compress = opt;
188				break;
189#endif
190#ifndef NO_COMPRESS_CREATE
191			case 'Z':
192				compress = opt;
193				break;
194#endif
195#ifndef NO_GZIP_CREATE
196			case 'z':
197				compress = opt;
198				break;
199#endif
200			default:
201				usage();
202			}
203		}
204	}
205
206	switch (mode) {
207#ifndef NO_CREATE
208	case 'c':
209		create(filename, compress, argv);
210		break;
211#endif
212	case 't':
213		extract(filename, 0, flags);
214		break;
215	case 'x':
216		extract(filename, 1, flags);
217		break;
218	}
219
220	return (0);
221}
222
223
224#ifndef NO_CREATE
225static char buff[16384];
226
227static void
228create(const char *filename, int compress, const char **argv)
229{
230	struct archive *a;
231	struct archive *disk;
232	struct archive_entry *entry;
233	ssize_t len;
234	int fd;
235
236	a = archive_write_new();
237	switch (compress) {
238#ifndef NO_BZIP2_CREATE
239	case 'j': case 'y':
240		archive_write_set_compression_bzip2(a);
241		break;
242#endif
243#ifndef NO_COMPRESS_CREATE
244	case 'Z':
245		archive_write_set_compression_compress(a);
246		break;
247#endif
248#ifndef NO_GZIP_CREATE
249	case 'z':
250		archive_write_set_compression_gzip(a);
251		break;
252#endif
253	default:
254		archive_write_set_compression_none(a);
255		break;
256	}
257	archive_write_set_format_ustar(a);
258	if (strcmp(filename, "-") == 0)
259		filename = NULL;
260	archive_write_open_file(a, filename);
261
262	disk = archive_read_disk_new();
263#ifndef NO_LOOKUP
264	archive_read_disk_set_standard_lookup(disk);
265#endif
266	while (*argv != NULL) {
267		struct tree *t = tree_open(*argv);
268		while (tree_next(t)) {
269			entry = archive_entry_new();
270			archive_entry_set_pathname(entry, tree_current_path(t));
271			archive_read_disk_entry_from_file(disk, entry, -1,
272			    tree_current_stat(t));
273			if (verbose) {
274				msg("a ");
275				msg(tree_current_path(t));
276			}
277			archive_write_header(a, entry);
278			fd = open(tree_current_access_path(t), O_RDONLY);
279			len = read(fd, buff, sizeof(buff));
280			while (len > 0) {
281				archive_write_data(a, buff, len);
282				len = read(fd, buff, sizeof(buff));
283			}
284			close(fd);
285			archive_entry_free(entry);
286			if (verbose)
287				msg("\n");
288		}
289		argv++;
290	}
291	archive_write_close(a);
292	archive_write_finish(a);
293}
294#endif
295
296static void
297extract(const char *filename, int do_extract, int flags)
298{
299	struct archive *a;
300	struct archive *ext;
301	struct archive_entry *entry;
302	int r;
303
304	a = archive_read_new();
305	ext = archive_write_disk_new();
306	archive_write_disk_set_options(ext, flags);
307#ifndef NO_BZIP2_EXTRACT
308	archive_read_support_compression_bzip2(a);
309#endif
310#ifndef NO_GZIP_EXTRACT
311	archive_read_support_compression_gzip(a);
312#endif
313#ifndef NO_COMPRESS_EXTRACT
314	archive_read_support_compression_compress(a);
315#endif
316#ifndef NO_TAR_EXTRACT
317	archive_read_support_format_tar(a);
318#endif
319#ifndef NO_CPIO_EXTRACT
320	archive_read_support_format_cpio(a);
321#endif
322#ifndef NO_LOOKUP
323	archive_write_disk_set_standard_lookup(ext);
324#endif
325	if (filename != NULL && strcmp(filename, "-") == 0)
326		filename = NULL;
327	if ((r = archive_read_open_file(a, filename, 10240))) {
328		errmsg(archive_error_string(a));
329		errmsg("\n");
330		exit(r);
331	}
332	for (;;) {
333		r = archive_read_next_header(a, &entry);
334		if (r == ARCHIVE_EOF)
335			break;
336		if (r != ARCHIVE_OK) {
337			errmsg(archive_error_string(a));
338			errmsg("\n");
339			exit(1);
340		}
341		if (verbose && do_extract)
342			msg("x ");
343		if (verbose || !do_extract)
344			msg(archive_entry_pathname(entry));
345		if (do_extract) {
346			r = archive_write_header(ext, entry);
347			if (r != ARCHIVE_OK)
348				errmsg(archive_error_string(a));
349			else
350				copy_data(a, ext);
351		}
352		if (verbose || !do_extract)
353			msg("\n");
354	}
355	archive_read_close(a);
356	archive_read_finish(a);
357	exit(0);
358}
359
360static int
361copy_data(struct archive *ar, struct archive *aw)
362{
363	int r;
364	const void *buff;
365	size_t size;
366	off_t offset;
367
368	for (;;) {
369		r = archive_read_data_block(ar, &buff, &size, &offset);
370		if (r == ARCHIVE_EOF) {
371			errmsg(archive_error_string(ar));
372			return (ARCHIVE_OK);
373		}
374		if (r != ARCHIVE_OK)
375			return (r);
376		r = archive_write_data_block(aw, buff, size, offset);
377		if (r != ARCHIVE_OK) {
378			errmsg(archive_error_string(ar));
379			return (r);
380		}
381	}
382}
383
384static void
385msg(const char *m)
386{
387	write(1, m, strlen(m));
388}
389
390static void
391errmsg(const char *m)
392{
393	write(2, m, strlen(m));
394}
395
396static void
397usage(void)
398{
399/* Many program options depend on compile options. */
400	const char *m = "Usage: minitar [-"
401#ifndef NO_CREATE
402	    "c"
403#endif
404#ifndef	NO_BZIP2
405	    "j"
406#endif
407	    "tvx"
408#ifndef NO_BZIP2
409	    "y"
410#endif
411#ifndef NO_COMPRESS
412	    "Z"
413#endif
414#ifndef NO_GZIP
415	    "z"
416#endif
417	    "] [-f file] [file]\n";
418
419	errmsg(m);
420	exit(1);
421}
422