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->new_stream_list,
51                                               lte_list_head);
52                         }
53                 }
54         }
55         return 0;
56 }
57
58 static void
59 inode_move_ltes_to_table(struct wim_inode *inode,
60                          struct wim_lookup_table *src_lookup_table,
61                          struct wim_lookup_table *dest_lookup_table,
62                          struct list_head *lte_list_head)
63 {
64         struct wim_lookup_table_entry *src_lte, *dest_lte;
65         unsigned i;
66
67         for (i = 0; i <= inode->i_num_ads; i++) {
68                 src_lte = inode_stream_lte_unresolved(inode, i, src_lookup_table);
69                 if (src_lte) {
70                         dest_lte = inode_stream_lte_unresolved(inode, i,
71                                                                dest_lookup_table);
72                         if (!dest_lte) {
73                                 struct list_head *next;
74
75                                 wimlib_assert(!list_empty(lte_list_head));
76                                 next = lte_list_head->next;
77                                 list_del(next);
78                                 dest_lte = container_of(next,
79                                                         struct wim_lookup_table_entry,
80                                                         new_stream_list);
81                                 dest_lte->part_number = 1;
82                                 dest_lte->refcnt = 0;
83                                 wimlib_assert(hashes_equal(dest_lte->hash, src_lte->hash));
84                                 lookup_table_insert(dest_lookup_table, dest_lte);
85                         }
86                         dest_lte->refcnt += inode->i_nlink;
87                 }
88         }
89 }
90
91 /*
92  * Exports an image, or all the images, from a WIM file, into another WIM file.
93  */
94 WIMLIBAPI int
95 wimlib_export_image(WIMStruct *src_wim,
96                     int src_image,
97                     WIMStruct *dest_wim,
98                     const tchar *dest_name,
99                     const tchar *dest_description,
100                     int export_flags,
101                     WIMStruct **additional_swms,
102                     unsigned num_additional_swms,
103                     wimlib_progress_func_t progress_func)
104 {
105         int ret;
106         struct wim_lookup_table *joined_tab, *src_wim_tab_save;
107         struct wim_image_metadata *src_imd;
108         struct list_head lte_list_head;
109         struct wim_inode *inode;
110
111         if (dest_wim->hdr.total_parts != 1) {
112                 ERROR("Exporting an image to a split WIM is "
113                       "unsupported");
114                 return WIMLIB_ERR_SPLIT_UNSUPPORTED;
115         }
116
117         if (src_image == WIMLIB_ALL_IMAGES) {
118                 if (src_wim->hdr.image_count > 1) {
119
120                         /* multi-image export. */
121
122                         if ((export_flags & WIMLIB_EXPORT_FLAG_BOOT) &&
123                               (src_wim->hdr.boot_idx == 0))
124                         {
125                                 /* Specifying the boot flag on a multi-image
126                                  * source WIM makes the boot index default to
127                                  * the bootable image in the source WIM.  It is
128                                  * an error if there is no such bootable image.
129                                  * */
130                                 ERROR("Cannot specify `boot' flag when "
131                                       "exporting multiple images from a WIM "
132                                       "with no bootable images");
133                                 return WIMLIB_ERR_INVALID_PARAM;
134                         }
135                         if (dest_name || dest_description) {
136                                 ERROR("Image name or image description was "
137                                       "specified, but we are exporting "
138                                       "multiple images");
139                                 return WIMLIB_ERR_INVALID_PARAM;
140                         }
141                         for (int i = 1; i <= src_wim->hdr.image_count; i++) {
142                                 int new_flags = export_flags;
143
144                                 if (i != src_wim->hdr.boot_idx)
145                                         new_flags &= ~WIMLIB_EXPORT_FLAG_BOOT;
146
147                                 ret = wimlib_export_image(src_wim, i, dest_wim,
148                                                           NULL, NULL,
149                                                           new_flags,
150                                                           additional_swms,
151                                                           num_additional_swms,
152                                                           progress_func);
153                                 if (ret)
154                                         return ret;
155                         }
156                         return 0;
157                 } else if (src_wim->hdr.image_count == 1) {
158                         src_image = 1;
159                 } else {
160                         return 0;
161                 }
162         }
163
164         if (!dest_name) {
165                 dest_name = wimlib_get_image_name(src_wim, src_image);
166                 DEBUG("Using name `%"TS"' for source image %d",
167                       dest_name, src_image);
168         }
169
170         if (!dest_description) {
171                 dest_description = wimlib_get_image_description(src_wim,
172                                                                 src_image);
173                 DEBUG("Using description `%"TS"' for source image %d",
174                       dest_description, src_image);
175         }
176
177         DEBUG("Exporting image %d from `%"TS"'", src_image, src_wim->filename);
178
179         if (wimlib_image_name_in_use(dest_wim, dest_name)) {
180                 ERROR("There is already an image named `%"TS"' in the "
181                       "destination WIM", dest_name);
182                 return WIMLIB_ERR_IMAGE_NAME_COLLISION;
183         }
184
185         ret = verify_swm_set(src_wim, additional_swms, num_additional_swms);
186         if (ret)
187                 return ret;
188
189         if (num_additional_swms) {
190                 ret = new_joined_lookup_table(src_wim, additional_swms,
191                                               num_additional_swms,
192                                               &joined_tab);
193                 if (ret)
194                         return ret;
195                 src_wim_tab_save = src_wim->lookup_table;
196                 src_wim->lookup_table = joined_tab;
197         }
198
199         ret = select_wim_image(src_wim, src_image);
200         if (ret) {
201                 ERROR("Could not select image %d from the WIM `%"TS"' "
202                       "to export it", src_image, src_wim->filename);
203                 goto out;
204         }
205
206         /* Pre-allocate the new lookup table entries that will be needed.  This
207          * way, it's not possible to run out of memory part-way through
208          * modifying the lookup table of the destination WIM. */
209         for_lookup_table_entry(src_wim->lookup_table, lte_zero_out_refcnt, NULL);
210         src_imd = wim_get_current_image_metadata(src_wim);
211         INIT_LIST_HEAD(&lte_list_head);
212         image_for_each_inode(inode, src_imd) {
213                 ret = inode_allocate_needed_ltes(inode,
214                                                  src_wim->lookup_table,
215                                                  dest_wim->lookup_table,
216                                                  &lte_list_head);
217                 if (ret)
218                         goto out_free_ltes;
219         }
220
221         ret = xml_export_image(src_wim->wim_info, src_image,
222                                &dest_wim->wim_info, dest_name,
223                                dest_description);
224         if (ret)
225                 goto out_free_ltes;
226
227         ret = append_image_metadata(dest_wim, src_imd);
228         if (ret)
229                 goto out_xml_delete_image;
230
231         /* The `struct image_metadata' is now referenced by both the @src_wim
232          * and the @dest_wim. */
233         src_imd->refcnt++;
234
235         /* All memory allocations have been taken care of, so it's no longer
236          * possible for this function to fail.  Go ahead and update the lookup
237          * table of the destination WIM and the boot index, if needed. */
238         image_for_each_inode(inode, src_imd) {
239                 inode_move_ltes_to_table(inode,
240                                          src_wim->lookup_table,
241                                          dest_wim->lookup_table,
242                                          &lte_list_head);
243         }
244
245         if (export_flags & WIMLIB_EXPORT_FLAG_BOOT)
246                 dest_wim->hdr.boot_idx = dest_wim->hdr.image_count;
247         ret = 0;
248         goto out;
249 out_xml_delete_image:
250         xml_delete_image(&dest_wim->wim_info, dest_wim->hdr.image_count + 1);
251 out_free_ltes:
252         {
253                 struct wim_lookup_table_entry *lte, *tmp;
254                 list_for_each_entry_safe(lte, tmp, &lte_list_head, new_stream_list)
255                         free_lookup_table_entry(lte);
256         }
257 out:
258         if (num_additional_swms) {
259                 free_lookup_table(src_wim->lookup_table);
260                 src_wim->lookup_table = src_wim_tab_save;
261         }
262         return ret;
263 }