cd024b1807bce4ba71f5e00b693be2aa80fd560e
[wimlib] / src / wim.c
1 /*
2  * wim.c
3  */
4
5 /*
6  * Copyright (C) 2010 Carl Thijssen
7  * Copyright (C) 2012 Eric Biggers
8  *
9  * wimlib - Library for working with WIM files
10  *
11  * This file is part of wimlib, a library for working with WIM files.
12  *
13  * wimlib is free software; you can redistribute it and/or modify it under the
14  * terms of the GNU General Public License as published by the Free
15  * Software Foundation; either version 3 of the License, or (at your option)
16  * any later version.
17  *
18  * wimlib is distributed in the hope that it will be useful, but WITHOUT ANY
19  * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
20  * A PARTICULAR PURPOSE. See the GNU General Public License for more
21  * details.
22  *
23  * You should have received a copy of the GNU General Public License
24  * along with wimlib; if not, see http://www.gnu.org/licenses/.
25  */
26
27 #include "config.h"
28 #include <limits.h>
29 #include <stdlib.h>
30 #include <stdarg.h>
31
32 #include "dentry.h"
33 #include <unistd.h>
34 #include <fcntl.h>
35
36 #ifdef WITH_NTFS_3G
37 #include <time.h>
38 #include <ntfs-3g/volume.h>
39 #endif
40
41 #include "wimlib_internal.h"
42 #include "io.h"
43 #include "lookup_table.h"
44 #include "xml.h"
45
46 static int print_metadata(WIMStruct *w)
47 {
48         DEBUG("Printing metadata for image %d", w->current_image);
49         print_security_data(wim_security_data(w));
50         return for_dentry_in_tree(wim_root_dentry(w), print_dentry,
51                                   w->lookup_table);
52 }
53
54
55 static int print_files(WIMStruct *w)
56 {
57         return for_dentry_in_tree(wim_root_dentry(w), print_dentry_full_path,
58                                   NULL);
59 }
60
61 WIMStruct *new_wim_struct()
62 {
63         WIMStruct *w = CALLOC(1, sizeof(WIMStruct));
64 #ifdef WITH_FUSE
65         if (pthread_mutex_init(&w->fp_tab_mutex, NULL) != 0) {
66                 ERROR_WITH_ERRNO("Failed to initialize mutex");
67                 FREE(w);
68                 w = NULL;
69         }
70 #endif
71         return w;
72
73 }
74
75 /*
76  * Calls a function on images in the WIM.  If @image is WIMLIB_ALL_IMAGES, @visitor
77  * is called on the WIM once for each image, with each image selected as the
78  * current image in turn.  If @image is a certain image, @visitor is called on
79  * the WIM only once, with that image selected.
80  */
81 int for_image(WIMStruct *w, int image, int (*visitor)(WIMStruct *))
82 {
83         int ret;
84         int start;
85         int end;
86         int i;
87
88         if (image == WIMLIB_ALL_IMAGES) {
89                 start = 1;
90                 end = w->hdr.image_count;
91         } else if (image >= 1 && image <= w->hdr.image_count) {
92                 start = image;
93                 end = image;
94         } else {
95                 return WIMLIB_ERR_INVALID_IMAGE;
96         }
97         for (i = start; i <= end; i++) {
98                 ret = select_wim_image(w, i);
99                 if (ret != 0)
100                         return ret;
101                 ret = visitor(w);
102                 if (ret != 0)
103                         return ret;
104         }
105         return 0;
106 }
107
108 static int sort_image_metadata_by_position(const void *p1, const void *p2)
109 {
110         const struct image_metadata *imd1 = p1;
111         const struct image_metadata *imd2 = p2;
112         u64 offset1 = imd1->metadata_lte->resource_entry.offset;
113         u64 offset2 = imd2->metadata_lte->resource_entry.offset;
114         if (offset1 < offset2)
115                 return -1;
116         else if (offset1 > offset2)
117                 return 1;
118         else
119                 return 0;
120 }
121
122 /*
123  * If @lte points to a metadata resource, append it to the list of metadata
124  * resources in the WIMStruct.  Otherwise, do nothing.
125  */
126 static int append_metadata_resource_entry(struct lookup_table_entry *lte,
127                                           void *wim_p)
128 {
129         WIMStruct *w = wim_p;
130         int ret = 0;
131
132         if (lte->resource_entry.flags & WIM_RESHDR_FLAG_METADATA) {
133                 if (w->current_image == w->hdr.image_count) {
134                         ERROR("The WIM header says there are %u images in the WIM,\n"
135                               "        but we found more metadata resources than this",
136                               w->hdr.image_count);
137                         ret = WIMLIB_ERR_IMAGE_COUNT;
138                 } else {
139                         DEBUG("Found metadata resource for image %u at "
140                               "offset %"PRIu64".",
141                               w->current_image + 1,
142                               lte->resource_entry.offset);
143                         w->image_metadata[
144                                 w->current_image++].metadata_lte = lte;
145                 }
146         }
147         return ret;
148 }
149
150 /* Returns the compression type given in the flags of a WIM header. */
151 int wim_hdr_flags_compression_type(int wim_hdr_flags)
152 {
153         if (wim_hdr_flags & WIM_HDR_FLAG_COMPRESSION) {
154                 if (wim_hdr_flags & WIM_HDR_FLAG_COMPRESS_LZX)
155                         return WIMLIB_COMPRESSION_TYPE_LZX;
156                 else if (wim_hdr_flags & WIM_HDR_FLAG_COMPRESS_XPRESS)
157                         return WIMLIB_COMPRESSION_TYPE_XPRESS;
158                 else
159                         return WIMLIB_COMPRESSION_TYPE_INVALID;
160         } else {
161                 return WIMLIB_COMPRESSION_TYPE_NONE;
162         }
163 }
164
165 /*
166  * Creates a WIMStruct for a new WIM file.
167  */
168 WIMLIBAPI int wimlib_create_new_wim(int ctype, WIMStruct **w_ret)
169 {
170         WIMStruct *w;
171         struct lookup_table *table;
172         int ret;
173
174         DEBUG("Creating new WIM with %s compression.",
175               wimlib_get_compression_type_string(ctype));
176
177         /* Allocate the WIMStruct. */
178         w = new_wim_struct();
179         if (!w)
180                 return WIMLIB_ERR_NOMEM;
181
182         ret = init_header(&w->hdr, ctype);
183         if (ret != 0)
184                 goto out_free;
185
186         table = new_lookup_table(9001);
187         if (!table) {
188                 ret = WIMLIB_ERR_NOMEM;
189                 goto out_free;
190         }
191         w->lookup_table = table;
192         *w_ret = w;
193         return 0;
194 out_free:
195         FREE(w);
196         return ret;
197 }
198
199 WIMLIBAPI int wimlib_get_num_images(const WIMStruct *w)
200 {
201         return w->hdr.image_count;
202 }
203
204 int select_wim_image(WIMStruct *w, int image)
205 {
206         struct image_metadata *imd;
207
208         DEBUG("Selecting image %d", image);
209
210         if (image == w->current_image)
211                 return 0;
212
213         if (image < 1 || image > w->hdr.image_count) {
214                 ERROR("Cannot select image %d: There are only %u images",
215                       image, w->hdr.image_count);
216                 return WIMLIB_ERR_INVALID_IMAGE;
217         }
218
219         /* If a valid image is currently selected, it can be freed if it is not
220          * modified.  */
221         if (w->current_image != WIMLIB_NO_IMAGE) {
222                 imd = wim_get_current_image_metadata(w);
223                 if (!imd->modified) {
224                         DEBUG("Freeing image %u", w->current_image);
225                         destroy_image_metadata(imd, NULL);
226                         imd->root_dentry = NULL;
227                         imd->security_data = NULL;
228                         INIT_HLIST_HEAD(&imd->inode_list);
229                 }
230         }
231
232         w->current_image = image;
233         imd = wim_get_current_image_metadata(w);
234
235         if (imd->root_dentry) {
236                 return 0;
237         } else {
238                 #ifdef ENABLE_DEBUG
239                 DEBUG("Reading metadata resource specified by the following "
240                       "lookup table entry:");
241                 print_lookup_table_entry(imd->metadata_lte);
242                 #endif
243                 return read_metadata_resource(w, imd);
244         }
245 }
246
247
248 /* Returns the compression type of the WIM file. */
249 WIMLIBAPI int wimlib_get_compression_type(const WIMStruct *w)
250 {
251         return wim_hdr_flags_compression_type(w->hdr.flags);
252 }
253
254 WIMLIBAPI const char *wimlib_get_compression_type_string(int ctype)
255 {
256         switch (ctype) {
257                 case WIMLIB_COMPRESSION_TYPE_NONE:
258                         return "None";
259                 case WIMLIB_COMPRESSION_TYPE_LZX:
260                         return "LZX";
261                 case WIMLIB_COMPRESSION_TYPE_XPRESS:
262                         return "XPRESS";
263                 default:
264                         return "Invalid";
265         }
266 }
267
268 /*
269  * Returns the number of an image in the WIM file, given a string that is either
270  * the number of the image, or the name of the image.  The images are numbered
271  * starting at 1.
272  */
273 WIMLIBAPI int wimlib_resolve_image(WIMStruct *w, const char *image_name_or_num)
274 {
275         char *p;
276         int image;
277         int i;
278
279         if (!image_name_or_num || !*image_name_or_num)
280                 return WIMLIB_NO_IMAGE;
281
282         if (strcmp(image_name_or_num, "all") == 0
283             || strcmp(image_name_or_num, "*") == 0)
284                 return WIMLIB_ALL_IMAGES;
285         image = strtol(image_name_or_num, &p, 10);
286         if (p != image_name_or_num && *p == '\0' && image > 0) {
287                 if (image > w->hdr.image_count)
288                         return WIMLIB_NO_IMAGE;
289                 return image;
290         } else {
291                 for (i = 1; i <= w->hdr.image_count; i++) {
292                         if (strcmp(image_name_or_num,
293                                    wimlib_get_image_name(w, i)) == 0)
294                                 return i;
295                 }
296                 return WIMLIB_NO_IMAGE;
297         }
298 }
299
300
301 /* Prints some basic information about a WIM file. */
302 WIMLIBAPI void wimlib_print_wim_information(const WIMStruct *w)
303 {
304         const struct wim_header *hdr;
305
306         hdr = &w->hdr;
307         puts("WIM Information:");
308         puts("----------------");
309         printf("Path:           %s\n", w->filename);
310         fputs ("GUID:           0x", stdout);
311         print_byte_field(hdr->guid, WIM_GID_LEN);
312         putchar('\n');
313         printf("Image Count:    %d\n", hdr->image_count);
314         printf("Compression:    %s\n", wimlib_get_compression_type_string(
315                                                 wimlib_get_compression_type(w)));
316         printf("Part Number:    %d/%d\n", hdr->part_number, hdr->total_parts);
317         printf("Boot Index:     %d\n", hdr->boot_idx);
318         printf("Size:           %"PRIu64" bytes\n",
319                                 wim_info_get_total_bytes(w->wim_info));
320         printf("Integrity Info: %s\n", (w->hdr.integrity.size != 0) ? "yes" : "no");
321         putchar('\n');
322 }
323
324 WIMLIBAPI bool wimlib_has_integrity_table(const WIMStruct *w)
325 {
326         return w->hdr.integrity.size != 0;
327 }
328
329 WIMLIBAPI void wimlib_print_available_images(const WIMStruct *w, int image)
330 {
331         int first;
332         int last;
333         int i;
334         int n;
335         if (image == WIMLIB_ALL_IMAGES) {
336                 n = printf("Available Images:\n");
337                 first = 1;
338                 last = w->hdr.image_count;
339         } else if (image >= 1 && image <= w->hdr.image_count) {
340                 n = printf("Information for Image %d\n", image);
341                 first = image;
342                 last = image;
343         } else {
344                 printf("wimlib_print_available_images(): Invalid image %d",
345                        image);
346                 return;
347         }
348         for (i = 0; i < n - 1; i++)
349                 putchar('-');
350         putchar('\n');
351         for (i = first; i <= last; i++)
352                 print_image_info(w->wim_info, i);
353 }
354
355
356 /* Prints the metadata for the specified image, which may be WIMLIB_ALL_IMAGES, but
357  * not WIMLIB_NO_IMAGE. */
358 WIMLIBAPI int wimlib_print_metadata(WIMStruct *w, int image)
359 {
360         if (!w)
361                 return WIMLIB_ERR_INVALID_PARAM;
362         if (w->hdr.part_number != 1) {
363                 ERROR("Cannot show the metadata from part %hu of a %hu-part split WIM!",
364                        w->hdr.part_number, w->hdr.total_parts);
365                 ERROR("Select the first part of the split WIM to see the metadata.");
366                 return WIMLIB_ERR_SPLIT_UNSUPPORTED;
367         }
368         return for_image(w, image, print_metadata);
369 }
370
371 WIMLIBAPI int wimlib_print_files(WIMStruct *w, int image)
372 {
373         if (!w)
374                 return WIMLIB_ERR_INVALID_PARAM;
375         if (w->hdr.part_number != 1) {
376                 ERROR("Cannot list the files from part %hu of a %hu-part split WIM!",
377                        w->hdr.part_number, w->hdr.total_parts);
378                 ERROR("Select the first part of the split WIM if you'd like to list the files.");
379                 return WIMLIB_ERR_SPLIT_UNSUPPORTED;
380         }
381         return for_image(w, image, print_files);
382 }
383
384 /* Sets the index of the bootable image. */
385 WIMLIBAPI int wimlib_set_boot_idx(WIMStruct *w, int boot_idx)
386 {
387         if (!w)
388                 return WIMLIB_ERR_INVALID_PARAM;
389         if (w->hdr.total_parts != 1) {
390                 ERROR("Cannot modify the boot index of a split WIM!");
391                 return WIMLIB_ERR_SPLIT_UNSUPPORTED;
392         }
393         if (boot_idx < 0 || boot_idx > w->hdr.image_count)
394                 return WIMLIB_ERR_INVALID_IMAGE;
395         w->hdr.boot_idx = boot_idx;
396
397         if (boot_idx == 0) {
398                 memset(&w->hdr.boot_metadata_res_entry, 0,
399                        sizeof(struct resource_entry));
400         } else {
401                 memcpy(&w->hdr.boot_metadata_res_entry,
402                        &w->image_metadata[
403                           boot_idx - 1].metadata_lte->resource_entry,
404                        sizeof(struct resource_entry));
405         }
406
407         return 0;
408 }
409
410 WIMLIBAPI int wimlib_get_part_number(const WIMStruct *w, int *total_parts_ret)
411 {
412         if (total_parts_ret)
413                 *total_parts_ret = w->hdr.total_parts;
414         return w->hdr.part_number;
415 }
416
417
418 WIMLIBAPI int wimlib_get_boot_idx(const WIMStruct *w)
419 {
420         return w->hdr.boot_idx;
421 }
422
423 /*
424  * Begins the reading of a WIM file; opens the file and reads its header and
425  * lookup table, and optionally checks the integrity.
426  */
427 static int begin_read(WIMStruct *w, const char *in_wim_path, int open_flags,
428                       wimlib_progress_func_t progress_func)
429 {
430         int ret;
431         uint xml_num_images;
432
433         DEBUG("Reading the WIM file `%s'", in_wim_path);
434
435         w->fp = fopen(in_wim_path, "rb");
436         if (!w->fp) {
437                 ERROR_WITH_ERRNO("Failed to open `%s' for reading",
438                                  in_wim_path);
439                 return WIMLIB_ERR_OPEN;
440         }
441
442         /* The absolute path to the WIM is requested so that wimlib_overwrite()
443          * still works even if the process changes its working directory.  This
444          * actually happens if a WIM is mounted read-write, since the FUSE
445          * thread changes directory to "/", and it needs to be able to find the
446          * WIM file again.
447          *
448          * This will break if the full path to the WIM changes in the
449          * intervening time...
450          */
451         w->filename = realpath(in_wim_path, NULL);
452         if (!w->filename) {
453                 ERROR_WITH_ERRNO("Failed to resolve WIM filename");
454                 ret = WIMLIB_ERR_NOMEM;
455                 goto out_close;
456         }
457
458         ret = read_header(w->fp, &w->hdr, open_flags);
459         if (ret != 0)
460                 goto out_close;
461
462         DEBUG("Wim file contains %u images", w->hdr.image_count);
463
464         /* If the boot index is invalid, print a warning and set it to 0 */
465         if (w->hdr.boot_idx > w->hdr.image_count) {
466                 WARNING("In `%s', image %u is marked as bootable, "
467                         "but there are only %u images in the WIM",
468                         in_wim_path, w->hdr.boot_idx, w->hdr.image_count);
469                 w->hdr.boot_idx = 0;
470         }
471
472         if (wimlib_get_compression_type(w) == WIMLIB_COMPRESSION_TYPE_INVALID) {
473                 ERROR("Invalid compression type (WIM header flags = %x)",
474                       w->hdr.flags);
475                 ret = WIMLIB_ERR_INVALID_COMPRESSION_TYPE;
476                 goto out_close;
477         }
478
479         if (open_flags & WIMLIB_OPEN_FLAG_CHECK_INTEGRITY) {
480                 ret = check_wim_integrity(w, progress_func);
481                 if (ret == WIM_INTEGRITY_NONEXISTENT) {
482                         WARNING("No integrity information for `%s'; skipping "
483                                 "integrity check.", w->filename);
484                 } else if (ret == WIM_INTEGRITY_NOT_OK) {
485                         ERROR("WIM is not intact! (Failed integrity check)");
486                         ret = WIMLIB_ERR_INTEGRITY;
487                         goto out_close;
488                 } else if (ret != 0) {
489                         goto out_close;
490                 }
491         }
492
493         if (resource_is_compressed(&w->hdr.lookup_table_res_entry)) {
494                 ERROR("Didn't expect a compressed lookup table!");
495                 ERROR("Ask the author to implement support for this.");
496                 ret = WIMLIB_ERR_COMPRESSED_LOOKUP_TABLE;
497                 goto out_close;
498         }
499
500         ret = read_lookup_table(w);
501         if (ret != 0)
502                 goto out_close;
503
504         w->image_metadata = CALLOC(w->hdr.image_count,
505                                    sizeof(struct image_metadata));
506
507         if (!w->image_metadata) {
508                 ERROR("Failed to allocate memory for %u metadata structures",
509                       w->hdr.image_count);
510                 ret = WIMLIB_ERR_NOMEM;
511                 goto out_free_lookup_table;
512         }
513         w->current_image = 0;
514
515         DEBUG("Looking for metadata resources in the lookup table.");
516
517         /* Find the images in the WIM by searching the lookup table. */
518         ret = for_lookup_table_entry(w->lookup_table,
519                                      append_metadata_resource_entry, w);
520
521         if (ret != 0)
522                 goto out_free_image_metadata;
523
524         /* Make sure all the expected images were found.  (We already have
525          * returned false if *extra* images were found) */
526         if (w->current_image != w->hdr.image_count &&
527             w->hdr.part_number == 1)
528         {
529                 ERROR("Only found %u images in WIM, but expected %u",
530                       w->current_image, w->hdr.image_count);
531                 ret = WIMLIB_ERR_IMAGE_COUNT;
532                 goto out_free_image_metadata;
533         }
534
535         /* Sort images by the position of their metadata resources.  I'm
536          * assuming that is what determines the other of the images in the WIM
537          * file, rather than their order in the lookup table, which is random
538          * because of hashing. */
539         qsort(w->image_metadata, w->current_image,
540               sizeof(struct image_metadata), sort_image_metadata_by_position);
541
542         w->current_image = WIMLIB_NO_IMAGE;
543
544         /* Read the XML data. */
545         ret = read_xml_data(w->fp, &w->hdr.xml_res_entry,
546                             &w->xml_data, &w->wim_info);
547
548         if (ret != 0)
549                 goto out_free_image_metadata;
550
551         xml_num_images = wim_info_get_num_images(w->wim_info);
552         if (xml_num_images != w->hdr.image_count) {
553                 ERROR("In the file `%s', there are %u <IMAGE> elements "
554                       "in the XML data,", in_wim_path, xml_num_images);
555                 ERROR("but %u images in the WIM!  There must be exactly one "
556                       "<IMAGE> element per image.", w->hdr.image_count);
557                 ret = WIMLIB_ERR_IMAGE_COUNT;
558                 goto out_free_xml_data;
559         }
560
561         DEBUG("Done beginning read of WIM file `%s'.", in_wim_path);
562         return 0;
563
564         //
565         // Everything is freed in wimlib_free() anyway, so no need to roll back
566         // changes here.
567         //
568 out_free_xml_data:
569         /*FREE(w->xml_data);*/
570         /*w->xml_data = NULL;*/
571         /*free_wim_info(w->wim_info);*/
572         /*w->wim_info = NULL;*/
573 out_free_image_metadata:
574         /*FREE(w->image_metadata);*/
575         /*w->image_metadata = NULL;*/
576         /*w->current_image = WIMLIB_NO_IMAGE;*/
577 out_free_lookup_table:
578         /*free_lookup_table(w->lookup_table);*/
579         /*w->lookup_table = NULL;*/
580 out_close:
581         /*fclose(w->fp);*/
582         /*w->fp = NULL;*/
583 out:
584         return ret;
585 }
586
587
588 /*
589  * Opens a WIM file and creates a WIMStruct for it.
590  */
591 WIMLIBAPI int wimlib_open_wim(const char *wim_file, int open_flags,
592                               WIMStruct **w_ret,
593                               wimlib_progress_func_t progress_func)
594 {
595         WIMStruct *w;
596         int ret;
597
598         if (!wim_file || !w_ret)
599                 return WIMLIB_ERR_INVALID_PARAM;
600         w = new_wim_struct();
601         if (!w) {
602                 ERROR("Failed to allocate memory for WIMStruct");
603                 return WIMLIB_ERR_NOMEM;
604         }
605
606         ret = begin_read(w, wim_file, open_flags, progress_func);
607         if (ret == 0) {
608                 *w_ret = w;
609         } else {
610                 DEBUG("Could not begin reading the WIM file `%s'", wim_file);
611                 wimlib_free(w);
612         }
613         return ret;
614 }
615
616 /* Frees the memory for the WIMStruct, including all internal memory; also
617  * closes all files associated with the WIMStruct.  */
618 WIMLIBAPI void wimlib_free(WIMStruct *w)
619 {
620         DEBUG2("Freeing WIMStruct");
621
622         if (!w)
623                 return;
624         if (w->fp)
625                 fclose(w->fp);
626         if (w->out_fp)
627                 fclose(w->out_fp);
628
629 #ifdef WITH_FUSE
630         if (w->fp_tab) {
631                 for (size_t i = 0; i < w->num_allocated_fps; i++)
632                         if (w->fp_tab[i])
633                                 fclose(w->fp_tab[i]);
634                 FREE(w->fp_tab);
635         }
636         pthread_mutex_destroy(&w->fp_tab_mutex);
637 #endif
638
639         free_lookup_table(w->lookup_table);
640
641         FREE(w->filename);
642         FREE(w->xml_data);
643         free_wim_info(w->wim_info);
644         if (w->image_metadata) {
645                 for (uint i = 0; i < w->hdr.image_count; i++)
646                         destroy_image_metadata(&w->image_metadata[i], NULL);
647                 FREE(w->image_metadata);
648         }
649 #ifdef WITH_NTFS_3G
650         if (w->ntfs_vol) {
651                 DEBUG("Unmounting NTFS volume");
652                 ntfs_umount(w->ntfs_vol, FALSE);
653         }
654 #endif
655         FREE(w);
656 }