1 /*
2 * e2initrd_helper.c - Get the filesystem table
3 *
4 * Copyright 2004 by Theodore Ts'o.
5 *
6 * %Begin-Header%
7 * This file may be redistributed under the terms of the GNU Public
8 * License.
9 * %End-Header%
10 */
11
12 #include <stdio.h>
13 #include <unistd.h>
14 #ifdef HAVE_STDLIB_H
15 #include <stdlib.h>
16 #endif
17 #include <ctype.h>
18 #include <string.h>
19 #include <time.h>
20 #ifdef HAVE_ERRNO_H
21 #include <errno.h>
22 #endif
23 #include <sys/types.h>
24 #include <sys/stat.h>
25 #include <fcntl.h>
26 #include <utime.h>
27 #ifdef HAVE_GETOPT_H
28 #include <getopt.h>
29 #else
30 extern int optind;
31 extern char *optarg;
32 #endif
33
34 #include "ext2fs/ext2_fs.h"
35 #include "ext2fs/ext2fs.h"
36 #include "blkid/blkid.h"
37
38 #include "../version.h"
39 #include "nls-enable.h"
40
41 const char * program_name = "get_fstab";
42 char * device_name;
43 static int open_flag;
44 static int root_type;
45 static blkid_cache cache = NULL;
46
47 struct mem_file {
48 char *buf;
49 int size;
50 int ptr;
51 };
52
53 struct fs_info {
54 char *device;
55 char *mountpt;
56 char *type;
57 char *opts;
58 int freq;
59 int passno;
60 int flags;
61 struct fs_info *next;
62 };
63
usage(void)64 static void usage(void)
65 {
66 fprintf(stderr,
67 _("Usage: %s -r device\n"), program_name);
68 exit (1);
69 }
70
get_file(ext2_filsys fs,const char * filename,struct mem_file * ret_file)71 static errcode_t get_file(ext2_filsys fs, const char * filename,
72 struct mem_file *ret_file)
73 {
74 errcode_t retval;
75 char *buf;
76 ext2_file_t e2_file;
77 unsigned int got;
78 struct ext2_inode inode;
79 ext2_ino_t ino;
80
81 ret_file->buf = 0;
82 ret_file->size = 0;
83 ret_file->ptr = 0;
84
85 retval = ext2fs_namei(fs, EXT2_ROOT_INO, EXT2_ROOT_INO,
86 filename, &ino);
87 if (retval)
88 return retval;
89
90 retval = ext2fs_read_inode(fs, ino, &inode);
91 if (retval)
92 return retval;
93
94 if (inode.i_size_high || (inode.i_size > 65536))
95 return EFBIG;
96
97 buf = malloc(inode.i_size + 1);
98 if (!buf)
99 return ENOMEM;
100 memset(buf, 0, inode.i_size+1);
101
102 retval = ext2fs_file_open(fs, ino, 0, &e2_file);
103 if (retval)
104 return retval;
105
106 retval = ext2fs_file_read(e2_file, buf, inode.i_size, &got);
107 if (retval)
108 goto errout;
109
110 retval = ext2fs_file_close(e2_file);
111 if (retval)
112 return retval;
113
114 ret_file->buf = buf;
115 ret_file->size = (int) got;
116
117 errout:
118 ext2fs_file_close(e2_file);
119 return retval;
120 }
121
get_line(struct mem_file * file)122 static char *get_line(struct mem_file *file)
123 {
124 char *cp, *ret;
125 int s = 0;
126
127 cp = file->buf + file->ptr;
128 while (*cp && *cp != '\n') {
129 cp++;
130 s++;
131 }
132 ret = malloc(s+1);
133 if (!ret)
134 return 0;
135 ret[s]=0;
136 memcpy(ret, file->buf + file->ptr, s);
137 while (*cp && (*cp == '\n' || *cp == '\r')) {
138 cp++;
139 s++;
140 }
141 file->ptr += s;
142 return ret;
143 }
144
mem_file_eof(struct mem_file * file)145 static int mem_file_eof(struct mem_file *file)
146 {
147 return (file->ptr >= file->size);
148 }
149
150 /*
151 * fstab parsing code
152 */
string_copy(const char * s)153 static char *string_copy(const char *s)
154 {
155 char *ret;
156
157 if (!s)
158 return 0;
159 ret = malloc(strlen(s)+1);
160 if (ret)
161 strcpy(ret, s);
162 return ret;
163 }
164
skip_over_blank(char * cp)165 static char *skip_over_blank(char *cp)
166 {
167 while (*cp && isspace(*cp))
168 cp++;
169 return cp;
170 }
171
skip_over_word(char * cp)172 static char *skip_over_word(char *cp)
173 {
174 while (*cp && !isspace(*cp))
175 cp++;
176 return cp;
177 }
178
parse_word(char ** buf)179 static char *parse_word(char **buf)
180 {
181 char *word, *next;
182
183 word = *buf;
184 if (*word == 0)
185 return 0;
186
187 word = skip_over_blank(word);
188 next = skip_over_word(word);
189 if (*next)
190 *next++ = 0;
191 *buf = next;
192 return word;
193 }
194
parse_escape(char * word)195 static void parse_escape(char *word)
196 {
197 char *p, *q;
198 int ac, i;
199
200 if (!word)
201 return;
202
203 for (p = word, q = word; *p; p++, q++) {
204 *q = *p;
205 if (*p != '\\')
206 continue;
207 if (*++p == 0)
208 break;
209 if (*p == 't') {
210 *q = '\t';
211 continue;
212 }
213 if (*p == 'n') {
214 *q = '\n';
215 continue;
216 }
217 if (!isdigit(*p)) {
218 *q = *p;
219 continue;
220 }
221 ac = 0;
222 for (i = 0; i < 3; i++, p++) {
223 if (!isdigit(*p))
224 break;
225 ac = (ac * 8) + (*p - '0');
226 }
227 *q = ac;
228 p--;
229 }
230 *q = 0;
231 }
232
parse_fstab_line(char * line,struct fs_info * fs)233 static int parse_fstab_line(char *line, struct fs_info *fs)
234 {
235 char *dev, *device, *mntpnt, *type, *opts, *freq, *passno, *cp;
236
237 if ((cp = strchr(line, '#')))
238 *cp = 0; /* Ignore everything after the comment char */
239 cp = line;
240
241 device = parse_word(&cp);
242 mntpnt = parse_word(&cp);
243 type = parse_word(&cp);
244 opts = parse_word(&cp);
245 freq = parse_word(&cp);
246 passno = parse_word(&cp);
247
248 if (!device)
249 return -1; /* Allow blank lines */
250
251 if (!mntpnt || !type)
252 return -1;
253
254 parse_escape(device);
255 parse_escape(mntpnt);
256 parse_escape(type);
257 parse_escape(opts);
258 parse_escape(freq);
259 parse_escape(passno);
260
261 dev = blkid_get_devname(cache, device, NULL);
262 if (dev)
263 device = dev;
264
265 if (strchr(type, ','))
266 type = 0;
267
268 fs->device = string_copy(device);
269 fs->mountpt = string_copy(mntpnt);
270 fs->type = string_copy(type);
271 fs->opts = string_copy(opts ? opts : "");
272 fs->freq = freq ? atoi(freq) : -1;
273 fs->passno = passno ? atoi(passno) : -1;
274 fs->flags = 0;
275 fs->next = NULL;
276
277 free(dev);
278
279 return 0;
280 }
281
free_fstab_line(struct fs_info * fs)282 static void free_fstab_line(struct fs_info *fs)
283 {
284 if (fs->device)
285 fs->device = 0;
286 if (fs->mountpt)
287 fs->mountpt = 0;
288 if (fs->type)
289 fs->type = 0;
290 if (fs->opts)
291 fs->opts = 0;
292 memset(fs, 0, sizeof(struct fs_info));
293 }
294
295
PRS(int argc,char ** argv)296 static void PRS(int argc, char **argv)
297 {
298 int c;
299
300 #ifdef ENABLE_NLS
301 setlocale(LC_MESSAGES, "");
302 setlocale(LC_CTYPE, "");
303 bindtextdomain(NLS_CAT_NAME, LOCALEDIR);
304 textdomain(NLS_CAT_NAME);
305 #endif
306
307 while ((c = getopt(argc, argv, "rv")) != EOF) {
308 switch (c) {
309 case 'r':
310 root_type++;
311 break;
312
313 case 'v':
314 printf("%s %s (%s)\n", program_name,
315 E2FSPROGS_VERSION, E2FSPROGS_DATE);
316 break;
317 default:
318 usage();
319 }
320 }
321 if (optind < argc - 1 || optind == argc)
322 usage();
323 device_name = blkid_get_devname(NULL, argv[optind], NULL);
324 if (!device_name) {
325 com_err("tune2fs", 0, _("Unable to resolve '%s'"),
326 argv[optind]);
327 exit(1);
328 }
329 }
330
get_root_type(ext2_filsys fs)331 static void get_root_type(ext2_filsys fs)
332 {
333 errcode_t retval;
334 struct mem_file file;
335 char *buf;
336 struct fs_info fs_info;
337 int ret;
338
339 retval = get_file(fs, "/etc/fstab", &file);
340
341 while (!mem_file_eof(&file)) {
342 buf = get_line(&file);
343 if (!buf)
344 continue;
345
346 ret = parse_fstab_line(buf, &fs_info);
347 if (ret < 0)
348 goto next_line;
349
350 if (!strcmp(fs_info.mountpt, "/"))
351 printf("%s\n", fs_info.type);
352
353 free_fstab_line(&fs_info);
354
355 next_line:
356 free(buf);
357 }
358 }
359
360
main(int argc,char ** argv)361 int main (int argc, char ** argv)
362 {
363 errcode_t retval;
364 ext2_filsys fs;
365 io_manager io_ptr;
366
367 add_error_table(&et_ext2_error_table);
368
369 blkid_get_cache(&cache, NULL);
370 PRS(argc, argv);
371
372 #ifdef CONFIG_TESTIO_DEBUG
373 if (getenv("TEST_IO_FLAGS") || getenv("TEST_IO_BLOCK")) {
374 io_ptr = test_io_manager;
375 test_io_backing_manager = unix_io_manager;
376 } else
377 #endif
378 io_ptr = unix_io_manager;
379 retval = ext2fs_open (device_name, open_flag, 0, 0, io_ptr, &fs);
380 if (retval)
381 exit(1);
382
383 if (root_type)
384 get_root_type(fs);
385
386 remove_error_table(&et_ext2_error_table);
387 return (ext2fs_close (fs) ? 1 : 0);
388 }
389