Fixes, comments
[wimlib] / src / export_image.c
1 /*
2  * export_image.c
3  */
4
5 /*
6  * Copyright (C) 2012, 2013 Eric Biggers
7  *
8  * This file is part of wimlib, a library for working with WIM files.
9  *
10  * wimlib is free software; you can redistribute it and/or modify it under the
11  * terms of the GNU General Public License as published by the Free
12  * Software Foundation; either version 3 of the License, or (at your option)
13  * any later version.
14  *
15  * wimlib is distributed in the hope that it will be useful, but WITHOUT ANY
16  * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
17  * A PARTICULAR PURPOSE. See the GNU General Public License for more
18  * details.
19  *
20  * You should have received a copy of the GNU General Public License
21  * along with wimlib; if not, see http://www.gnu.org/licenses/.
22  */
23
24 #include "wimlib_internal.h"
25 #include "dentry.h"
26 #include "lookup_table.h"
27 #include "xml.h"
28
29 static int
30 inode_allocate_needed_ltes(struct wim_inode *inode,
31                            struct wim_lookup_table *src_lookup_table,
32                            struct wim_lookup_table *dest_lookup_table,
33                            struct list_head *lte_list_head)
34 {
35         struct wim_lookup_table_entry *src_lte, *dest_lte;
36         unsigned i;
37
38         inode_unresolve_ltes(inode);
39         for (i = 0; i <= inode->i_num_ads; i++) {
40                 src_lte = inode_stream_lte_unresolved(inode, i,
41                                                       src_lookup_table);
42                 if (src_lte && src_lte->out_refcnt == 0) {
43                         src_lte->out_refcnt = 1;
44                         dest_lte = inode_stream_lte_unresolved(inode, i,
45                                                                dest_lookup_table);
46                         if (!dest_lte) {
47                                 dest_lte = clone_lookup_table_entry(src_lte);
48                                 if (!dest_lte)
49                                         return WIMLIB_ERR_NOMEM;
50                                 list_add_tail(&dest_lte->staging_list, lte_list_head);
51                         }
52                 }
53         }
54         return 0;
55 }
56
57 static void
58 inode_move_ltes_to_table(struct wim_inode *inode,
59                          struct wim_lookup_table *src_lookup_table,
60                          struct wim_lookup_table *dest_lookup_table,
61                          struct list_head *lte_list_head)
62 {
63         struct wim_lookup_table_entry *src_lte, *dest_lte;
64         unsigned i;
65
66         for (i = 0; i <= inode->i_num_ads; i++) {
67                 src_lte = inode_stream_lte_unresolved(inode, i, src_lookup_table);
68                 if (src_lte) {
69                         dest_lte = inode_stream_lte_unresolved(inode, i,
70                                                                dest_lookup_table);
71                         if (!dest_lte) {
72                                 struct list_head *next;
73
74                                 wimlib_assert(!list_empty(lte_list_head));
75                                 next = lte_list_head->next;
76                                 list_del(next);
77                                 dest_lte = container_of(next,
78                                                         struct wim_lookup_table_entry,
79                                                         staging_list);
80                                 dest_lte->part_number = 1;
81                                 dest_lte->refcnt = 0;
82                                 wimlib_assert(hashes_equal(dest_lte->hash, src_lte->hash));
83                                 lookup_table_insert(dest_lookup_table, dest_lte);
84                         }
85                         dest_lte->refcnt += inode->i_nlink;
86                 }
87         }
88 }
89
90 /*
91  * Exports an image, or all the images, from a WIM file, into another WIM file.
92  */
93 WIMLIBAPI int
94 wimlib_export_image(WIMStruct *src_wim,
95                     int src_image,
96                     WIMStruct *dest_wim,
97                     const tchar *dest_name,
98                     const tchar *dest_description,
99                     int export_flags,
100                     WIMStruct **additional_swms,
101                     unsigned num_additional_swms,
102                     wimlib_progress_func_t progress_func)
103 {
104         int ret;
105         struct wim_lookup_table *joined_tab, *src_wim_tab_save;
106         struct wim_image_metadata *src_imd;
107         struct list_head lte_list_head;
108         struct wim_inode *inode;
109
110         if (dest_wim->hdr.total_parts != 1) {
111                 ERROR("Exporting an image to a split WIM is "
112                       "unsupported");
113                 return WIMLIB_ERR_SPLIT_UNSUPPORTED;
114         }
115
116         if (src_image == WIMLIB_ALL_IMAGES) {
117                 if (src_wim->hdr.image_count > 1) {
118
119                         /* multi-image export. */
120
121                         if ((export_flags & WIMLIB_EXPORT_FLAG_BOOT) &&
122                               (src_wim->hdr.boot_idx == 0))
123                         {
124                                 /* Specifying the boot flag on a multi-image
125                                  * source WIM makes the boot index default to
126                                  * the bootable image in the source WIM.  It is
127                                  * an error if there is no such bootable image.
128                                  * */
129                                 ERROR("Cannot specify `boot' flag when "
130                                       "exporting multiple images from a WIM "
131                                       "with no bootable images");
132                                 return WIMLIB_ERR_INVALID_PARAM;
133                         }
134                         if (dest_name || dest_description) {
135                                 ERROR("Image name or image description was "
136                                       "specified, but we are exporting "
137                                       "multiple images");
138                                 return WIMLIB_ERR_INVALID_PARAM;
139                         }
140                         for (int i = 1; i <= src_wim->hdr.image_count; i++) {
141                                 int new_flags = export_flags;
142
143                                 if (i != src_wim->hdr.boot_idx)
144                                         new_flags &= ~WIMLIB_EXPORT_FLAG_BOOT;
145
146                                 ret = wimlib_export_image(src_wim, i, dest_wim,
147                                                           NULL, NULL,
148                                                           new_flags,
149                                                           additional_swms,
150                                                           num_additional_swms,
151                                                           progress_func);
152                                 if (ret)
153                                         return ret;
154                         }
155                         return 0;
156                 } else if (src_wim->hdr.image_count == 1) {
157                         src_image = 1;
158                 } else {
159                         return 0;
160                 }
161         }
162
163         if (!dest_name) {
164                 dest_name = wimlib_get_image_name(src_wim, src_image);
165                 DEBUG("Using name `%"TS"' for source image %d",
166                       dest_name, src_image);
167         }
168
169         if (!dest_description) {
170                 dest_description = wimlib_get_image_description(src_wim,
171                                                                 src_image);
172                 DEBUG("Using description `%"TS"' for source image %d",
173                       dest_description, src_image);
174         }
175
176         DEBUG("Exporting image %d from `%"TS"'", src_image, src_wim->filename);
177
178         if (wimlib_image_name_in_use(dest_wim, dest_name)) {
179                 ERROR("There is already an image named `%"TS"' in the "
180                       "destination WIM", dest_name);
181                 return WIMLIB_ERR_IMAGE_NAME_COLLISION;
182         }
183
184         ret = verify_swm_set(src_wim, additional_swms, num_additional_swms);
185         if (ret)
186                 return ret;
187
188         if (num_additional_swms) {
189                 ret = new_joined_lookup_table(src_wim, additional_swms,
190                                               num_additional_swms,
191                                               &joined_tab);
192                 if (ret)
193                         return ret;
194                 src_wim_tab_save = src_wim->lookup_table;
195                 src_wim->lookup_table = joined_tab;
196         }
197
198         ret = select_wim_image(src_wim, src_image);
199         if (ret) {
200                 ERROR("Could not select image %d from the WIM `%"TS"' "
201                       "to export it", src_image, src_wim->filename);
202                 goto out;
203         }
204
205         /* Pre-allocate the new lookup table entries that will be needed.  This
206          * way, it's not possible to run out of memory part-way through
207          * modifying the lookup table of the destination WIM. */
208         for_lookup_table_entry(src_wim->lookup_table, lte_zero_out_refcnt, NULL);
209         src_imd = wim_get_current_image_metadata(src_wim);
210         INIT_LIST_HEAD(&lte_list_head);
211         image_for_each_inode(inode, src_imd) {
212                 ret = inode_allocate_needed_ltes(inode,
213                                                  src_wim->lookup_table,
214                                                  dest_wim->lookup_table,
215                                                  &lte_list_head);
216                 if (ret)
217                         goto out_free_ltes;
218         }
219
220         ret = xml_export_image(src_wim->wim_info, src_image,
221                                &dest_wim->wim_info, dest_name,
222                                dest_description);
223         if (ret)
224                 goto out_free_ltes;
225
226         ret = append_image_metadata(dest_wim, src_imd);
227         if (ret)
228                 goto out_xml_delete_image;
229
230         /* The `struct image_metadata' is now referenced by both the @src_wim
231          * and the @dest_wim. */
232         src_imd->refcnt++;
233
234         /* All memory allocations have been taken care of, so it's no longer
235          * possible for this function to fail.  Go ahead and update the lookup
236          * table of the destination WIM and the boot index, if needed. */
237         image_for_each_inode(inode, src_imd) {
238                 inode_move_ltes_to_table(inode,
239                                          src_wim->lookup_table,
240                                          dest_wim->lookup_table,
241                                          &lte_list_head);
242         }
243
244         if (export_flags & WIMLIB_EXPORT_FLAG_BOOT)
245                 dest_wim->hdr.boot_idx = dest_wim->hdr.image_count;
246         ret = 0;
247         goto out;
248 out_xml_delete_image:
249         xml_delete_image(&dest_wim->wim_info, dest_wim->hdr.image_count + 1);
250 out_free_ltes:
251         {
252                 struct wim_lookup_table_entry *lte, *tmp;
253                 list_for_each_entry_safe(lte, tmp, &lte_list_head, staging_list)
254                         free_lookup_table_entry(lte);
255         }
256 out:
257         if (num_additional_swms) {
258                 free_lookup_table(src_wim->lookup_table);
259                 src_wim->lookup_table = src_wim_tab_save;
260         }
261         return ret;
262 }