summaryrefslogtreecommitdiff
path: root/archival/cpio.c
blob: 0d06149321125dba09918e48ba7f41a8056eb749 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
/* vi: set sw=4 ts=4: */
/*
 * Mini cpio implementation for busybox
 *
 * Copyright (C) 2001 by Glenn McGrath 
 *
 * 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 of the License, 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
 *
 * Limitations:
 *		Doesn't check CRC's
 *		Only supports new ASCII and CRC formats
 *
 */
#include <fcntl.h>
#include <getopt.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "unarchive.h"
#include "busybox.h"

typedef struct hardlinks_s {
	file_header_t *entry;
	int inode;
	struct hardlinks_s *next;
} hardlinks_t;

extern int cpio_main(int argc, char **argv)
{
	archive_handle_t *archive_handle;
	int opt;

	/* Initialise */
	archive_handle = init_handle();
	archive_handle->src_fd = fileno(stdin);
	archive_handle->seek = seek_by_char;
	archive_handle->action_header = header_list;

	while ((opt = getopt(argc, argv, "idmuvtF:")) != -1) {
		switch (opt) {
		case 'i': /* extract */
			archive_handle->action_data = data_extract_all;
			break;
		case 'd': /* create _leading_ directories */
			archive_handle->flags |= ARCHIVE_CREATE_LEADING_DIRS;
			break;
		case 'm': /* preserve modification time */
			archive_handle->flags |= ARCHIVE_PRESERVE_DATE;
			break;
		case 'v': /* verbosly list files */
			archive_handle->action_header = header_verbose_list;
			break;
		case 'u': /* unconditional */
			archive_handle->flags |= ARCHIVE_EXTRACT_UNCONDITIONAL;
			break;
		case 't': /* list files */
			archive_handle->action_header = header_list;
			break;
		case 'F':
			archive_handle->src_fd = xopen(optarg, O_RDONLY);
			archive_handle->seek = seek_by_jump;
			break;
		default:
			show_usage();
		}
	}

	while (optind < argc) {
		archive_handle->filter = filter_accept_list;
		archive_handle->accept = add_to_list(archive_handle->accept, argv[optind]);
		optind++;
	}

	while (1) {
	 	static hardlinks_t *saved_hardlinks = NULL;
 		static unsigned short pending_hardlinks = 0;
		file_header_t *file_header = archive_handle->file_header;
		char cpio_header[110];
		int namesize;
 		char dummy[16];
 		int major, minor, nlink, inode;
		char extract_flag;

		if (pending_hardlinks) { /* Deal with any pending hardlinks */
			hardlinks_t *tmp;
			hardlinks_t *oldtmp;

			tmp = saved_hardlinks;
			oldtmp = NULL;

			while (tmp) {
				error_msg_and_die("need to fix this\n");
				if (tmp->entry->link_name) { /* Found a hardlink ready to be extracted */
					file_header = tmp->entry;
					if (oldtmp) {
						oldtmp->next = tmp->next; /* Remove item from linked list */
					} else {
						saved_hardlinks = tmp->next;
					}
					free(tmp);
					continue;
				}
				oldtmp = tmp;
				tmp = tmp->next;
			}
			pending_hardlinks = 0; /* No more pending hardlinks, read next file entry */
	}

		/* There can be padding before archive header */
		data_align(archive_handle, 4);

		if (archive_xread_all_eof(archive_handle, cpio_header, 110) == 0) {
			return(EXIT_FAILURE);
		}
		archive_handle->offset += 110;

		if (strncmp(&cpio_header[0], "07070", 5) != 0) {
			printf("cpio header is %x-%x-%x-%x-%x\n",
				cpio_header[0],
				cpio_header[1],
				cpio_header[2],
				cpio_header[3],
				cpio_header[4]);
			error_msg_and_die("Unsupported cpio format");
		}
		
		if ((cpio_header[5] != '1') && (cpio_header[5] != '2')) {
			error_msg_and_die("Unsupported cpio format, use newc or crc");
	}

		sscanf(cpio_header, "%6c%8x%8x%8x%8x%8x%8lx%8lx%16c%8x%8x%8x%8c",
			dummy, &inode, (unsigned int*)&file_header->mode, 
			(unsigned int*)&file_header->uid, (unsigned int*)&file_header->gid,
			&nlink, &file_header->mtime, &file_header->size,
			dummy, &major, &minor, &namesize, dummy);

		file_header->name = (char *) xmalloc(namesize + 1);
		archive_xread_all(archive_handle, file_header->name, namesize); /* Read in filename */
		file_header->name[namesize] = '\0';
		archive_handle->offset += namesize;

		/* Update offset amount and skip padding before file contents */
		data_align(archive_handle, 4);

		if (strcmp(file_header->name, "TRAILER!!!") == 0) {
			printf("%d blocks\n", (int) (archive_handle->offset % 512 ? (archive_handle->offset / 512) + 1 : archive_handle->offset / 512)); /* Always round up */
			if (saved_hardlinks) { /* Bummer - we still have unresolved hardlinks */
				hardlinks_t *tmp = saved_hardlinks;
				hardlinks_t *oldtmp = NULL;
				while (tmp) {
					error_msg("%s not created: cannot resolve hardlink", tmp->entry->name);
					oldtmp = tmp;
					tmp = tmp->next;
					free (oldtmp->entry->name);
					free (oldtmp->entry);
					free (oldtmp);
				}
				saved_hardlinks = NULL;
				pending_hardlinks = 0;
	}
			return(EXIT_FAILURE);
		}

		if (S_ISLNK(file_header->mode)) {
			file_header->link_name = (char *) xmalloc(file_header->size + 1);
			archive_xread_all(archive_handle, file_header->link_name, file_header->size);
			file_header->link_name[file_header->size] = '\0';
			archive_handle->offset += file_header->size;
			file_header->size = 0; /* Stop possible seeks in future */
		}
		if (nlink > 1 && !S_ISDIR(file_header->mode)) {
			if (file_header->size == 0) { /* Put file on a linked list for later */
				hardlinks_t *new = xmalloc(sizeof(hardlinks_t));
				new->next = saved_hardlinks;
				new->inode = inode;
				new->entry = file_header;
				saved_hardlinks = new;
				continue;
			} else { /* Found the file with data in */
				hardlinks_t *tmp = saved_hardlinks;
				pending_hardlinks = 1;
				while (tmp) {
					if (tmp->inode == inode) {
						tmp->entry->link_name = xstrdup(file_header->name);
						nlink--;
					}
					tmp = tmp->next;
				}
				if (nlink > 1) {
					error_msg("error resolving hardlink: did you create the archive with GNU cpio 2.0-2.2?");
				}
			}
		}
		file_header->device = (major << 8) | minor;

		extract_flag = FALSE;
		if (archive_handle->filter(archive_handle->accept, archive_handle->reject, file_header->name) == EXIT_SUCCESS) {
			struct stat statbuf;

			extract_flag = TRUE;

			/* Check if the file already exists */
			if (lstat (file_header->name, &statbuf) == 0) {
				if ((archive_handle->flags & ARCHIVE_EXTRACT_UNCONDITIONAL) || (statbuf.st_mtime < file_header->mtime)) {
					/* Remove file if flag set or its older than the file to be extracted */
					if (unlink(file_header->name) == -1) {
						perror_msg_and_die("Couldnt remove old file");
					}
				} else {
					if (! archive_handle->flags & ARCHIVE_EXTRACT_QUIET) {
						error_msg("%s not created: newer or same age file exists", file_header->name);
					}
					extract_flag = FALSE;
				}
			}
			archive_handle->action_header(file_header);
		}

		archive_handle->action_header(file_header);
		if (extract_flag) {
			archive_handle->action_data(archive_handle);
		} else {
			data_skip(archive_handle);
		}
		archive_handle->offset += file_header->size;
	}

	return(EXIT_SUCCESS);
}