wimlib.net Git - wimlib/blob - src/export_image.c

   1 /*
   2  * export_image.c
   3  */
   4
   5 /*
   6  * Copyright (C) 2012, 2013, 2014 Eric Biggers
   7  *
   8  * This file is free software; you can redistribute it and/or modify it under
   9  * the terms of the GNU Lesser General Public License as published by the Free
  10  * Software Foundation; either version 3 of the License, or (at your option) any
  11  * later version.
  12  *
  13  * This file is distributed in the hope that it will be useful, but WITHOUT
  14  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
  15  * FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
  16  * details.
  17  *
  18  * You should have received a copy of the GNU Lesser General Public License
  19  * along with this file; if not, see http://www.gnu.org/licenses/.
  20  */
  21
  22 #ifdef HAVE_CONFIG_H
  23 #  include "config.h"
  24 #endif
  25
  26 #include "wimlib.h"
  27 #include "wimlib/error.h"
  28 #include "wimlib/inode.h"
  29 #include "wimlib/lookup_table.h"
  30 #include "wimlib/metadata.h"
  31 #include "wimlib/xml.h"
  32
  33 static int
  34 lte_set_not_exported(struct wim_lookup_table_entry *lte, void *_ignore)
  35 {
  36         lte->out_refcnt = 0;
  37         lte->was_exported = 0;
  38         return 0;
  39 }
  40
  41 static int
  42 lte_rollback_export(struct wim_lookup_table_entry *lte, void *_lookup_table)
  43 {
  44         struct wim_lookup_table *lookup_table = _lookup_table;
  45
  46         lte->refcnt -= lte->out_refcnt;
  47         if (lte->was_exported) {
  48                 lookup_table_unlink(lookup_table, lte);
  49                 free_lookup_table_entry(lte);
  50         }
  51         return 0;
  52 }
  53
  54 static int
  55 inode_export_streams(struct wim_inode *inode,
  56                      struct wim_lookup_table *src_lookup_table,
  57                      struct wim_lookup_table *dest_lookup_table,
  58                      bool gift)
  59 {
  60         unsigned i;
  61         const u8 *hash;
  62         struct wim_lookup_table_entry *src_lte, *dest_lte;
  63
  64         inode_unresolve_streams(inode);
  65         for (i = 0; i <= inode->i_num_ads; i++) {
  66
  67                 /* Retrieve SHA1 message digest of stream to export.  */
  68                 hash = inode_stream_hash(inode, i);
  69                 if (is_zero_hash(hash))  /* Empty stream?  */
  70                         continue;
  71
  72                 /* Search for the stream (via SHA1 message digest) in the
  73                  * destination WIM.  */
  74                 dest_lte = lookup_stream(dest_lookup_table, hash);
  75                 if (!dest_lte) {
  76                         /* Stream not yet present in destination WIM.  Search
  77                          * for it in the source WIM, then export it into the
  78                          * destination WIM.  */
  79                         src_lte = lookup_stream(src_lookup_table, hash);
  80                         if (!src_lte)
  81                                 return stream_not_found_error(inode, hash);
  82
  83                         if (gift) {
  84                                 dest_lte = src_lte;
  85                                 lookup_table_unlink(src_lookup_table, src_lte);
  86                         } else {
  87                                 dest_lte = clone_lookup_table_entry(src_lte);
  88                                 if (!dest_lte)
  89                                         return WIMLIB_ERR_NOMEM;
  90                         }
  91                         dest_lte->refcnt = 0;
  92                         dest_lte->out_refcnt = 0;
  93                         dest_lte->was_exported = 1;
  94                         lookup_table_insert(dest_lookup_table, dest_lte);
  95                 }
  96
  97                 /* Stream is present in destination WIM (either pre-existing,
  98                  * already exported, or just exported above).  Increment its
  99                  * reference count appropriately.   Note: we use 'refcnt' for
 100                  * the raw reference count, but 'out_refcnt' for references
 101                  * arising just from the export operation; this is used to roll
 102                  * back a failed export if needed.  */
 103                 dest_lte->refcnt += inode->i_nlink;
 104                 dest_lte->out_refcnt += inode->i_nlink;
 105         }
 106         return 0;
 107 }
 108
 109 /* API function documented in wimlib.h  */
 110 WIMLIBAPI int
 111 wimlib_export_image(WIMStruct *src_wim,
 112                     int src_image,
 113                     WIMStruct *dest_wim,
 114                     const tchar *dest_name,
 115                     const tchar *dest_description,
 116                     int export_flags)
 117 {
 118         int ret;
 119         int start_src_image;
 120         int end_src_image;
 121         int orig_dest_image_count;
 122         int image;
 123         bool all_images = (src_image == WIMLIB_ALL_IMAGES);
 124
 125         /* Check for sane parameters.  */
 126         if (export_flags & ~(WIMLIB_EXPORT_FLAG_BOOT |
 127                              WIMLIB_EXPORT_FLAG_NO_NAMES |
 128                              WIMLIB_EXPORT_FLAG_NO_DESCRIPTIONS |
 129                              WIMLIB_EXPORT_FLAG_GIFT |
 130                              WIMLIB_EXPORT_FLAG_WIMBOOT))
 131                 return WIMLIB_ERR_INVALID_PARAM;
 132
 133         if (src_wim == NULL || dest_wim == NULL)
 134                 return WIMLIB_ERR_INVALID_PARAM;
 135
 136         if (!wim_has_metadata(src_wim) || !wim_has_metadata(dest_wim))
 137                 return WIMLIB_ERR_METADATA_NOT_FOUND;
 138
 139         if (all_images) {
 140                 /* Multi-image export.  */
 141                 if ((!(export_flags & WIMLIB_EXPORT_FLAG_NO_NAMES) &&
 142                         dest_name) ||
 143                     (!(export_flags & WIMLIB_EXPORT_FLAG_NO_DESCRIPTIONS) &&
 144                         dest_description))
 145                 {
 146                         ERROR("Image name and description must be "
 147                               "left NULL for multi-image export");
 148                         return WIMLIB_ERR_INVALID_PARAM;
 149                 }
 150                 start_src_image = 1;
 151                 end_src_image = src_wim->hdr.image_count;
 152         } else {
 153                 start_src_image = src_image;
 154                 end_src_image = src_image;
 155         }
 156         orig_dest_image_count = dest_wim->hdr.image_count;
 157
 158         /* Stream checksums must be known before proceeding.  */
 159         ret = wim_checksum_unhashed_streams(src_wim);
 160         if (ret)
 161                 return ret;
 162         ret = wim_checksum_unhashed_streams(dest_wim);
 163         if (ret)
 164                 return ret;
 165
 166         /* Enable rollbacks  */
 167         for_lookup_table_entry(dest_wim->lookup_table, lte_set_not_exported, NULL);
 168
 169         /* Export each requested image.  */
 170         for (src_image = start_src_image;
 171              src_image <= end_src_image;
 172              src_image++)
 173         {
 174                 const tchar *next_dest_name, *next_dest_description;
 175                 struct wim_image_metadata *src_imd;
 176                 struct wim_inode *inode;
 177
 178                 /* Determine destination image name and description.  */
 179
 180                 if (export_flags & WIMLIB_EXPORT_FLAG_NO_NAMES)
 181                         next_dest_name = T("");
 182                 else if (dest_name)
 183                         next_dest_name = dest_name;
 184                 else
 185                         next_dest_name = wimlib_get_image_name(src_wim, src_image);
 186
 187                 if (export_flags & WIMLIB_EXPORT_FLAG_NO_DESCRIPTIONS)
 188                         next_dest_description = T("");
 189                 else if (dest_description)
 190                         next_dest_description = dest_description;
 191                 else
 192                         next_dest_description = wimlib_get_image_description(src_wim, src_image);
 193
 194                 /* Check for name conflict.  */
 195                 if (wimlib_image_name_in_use(dest_wim, next_dest_name)) {
 196                         ERROR("There is already an image named \"%"TS"\" "
 197                               "in the destination WIM", next_dest_name);
 198                         ret = WIMLIB_ERR_IMAGE_NAME_COLLISION;
 199                         goto out_rollback;
 200                 }
 201
 202                 /* Load metadata for source image into memory.  */
 203                 ret = select_wim_image(src_wim, src_image);
 204                 if (ret)
 205                         goto out_rollback;
 206
 207                 src_imd = wim_get_current_image_metadata(src_wim);
 208
 209                 /* Iterate through inodes in the source image and export their
 210                  * streams into the destination WIM.  */
 211                 image_for_each_inode(inode, src_imd) {
 212                         ret = inode_export_streams(inode,
 213                                                    src_wim->lookup_table,
 214                                                    dest_wim->lookup_table,
 215                                                    export_flags & WIMLIB_EXPORT_FLAG_GIFT);
 216                         if (ret)
 217                                 goto out_rollback;
 218                 }
 219
 220                 /* Export XML information into the destination WIM.  */
 221                 ret = xml_export_image(src_wim->wim_info, src_image,
 222                                        &dest_wim->wim_info, next_dest_name,
 223                                        next_dest_description);
 224                 if (ret)
 225                         goto out_rollback;
 226
 227                 /* Reference the source image metadata from the destination WIM.
 228                  */
 229                 ret = append_image_metadata(dest_wim, src_imd);
 230                 if (ret)
 231                         goto out_rollback;
 232                 src_imd->refcnt++;
 233
 234                 /* Lock the metadata into memory.  XXX: need better solution for
 235                  * this.  */
 236                 src_imd->modified = 1;
 237
 238         }
 239
 240         /* Image export complete.  Finish by setting any needed special metadata
 241          * on the destination WIM.  */
 242
 243         if (src_wim->hdr.flags & WIM_HDR_FLAG_RP_FIX)
 244                 dest_wim->hdr.flags |= WIM_HDR_FLAG_RP_FIX;
 245
 246         for (src_image = start_src_image;
 247              src_image <= end_src_image;
 248              src_image++)
 249         {
 250                 int dst_image = orig_dest_image_count + 1 +
 251                                 (src_image - start_src_image);
 252
 253                 if (export_flags & WIMLIB_EXPORT_FLAG_WIMBOOT)
 254                         wim_info_set_wimboot(dest_wim->wim_info, dst_image, true);
 255
 256                 if ((export_flags & WIMLIB_EXPORT_FLAG_BOOT) &&
 257                     (!all_images || src_image == src_wim->hdr.boot_idx))
 258                         dest_wim->hdr.boot_idx = dst_image;
 259         }
 260
 261         if (export_flags & WIMLIB_EXPORT_FLAG_GIFT) {
 262                 free_lookup_table(src_wim->lookup_table);
 263                 src_wim->lookup_table = NULL;
 264         }
 265         return 0;
 266
 267 out_rollback:
 268         while ((image = wim_info_get_num_images(dest_wim->wim_info))
 269                > orig_dest_image_count)
 270         {
 271                 xml_delete_image(&dest_wim->wim_info, image);
 272         }
 273         while (dest_wim->hdr.image_count > orig_dest_image_count)
 274         {
 275                 put_image_metadata(dest_wim->image_metadata[
 276                                         --dest_wim->hdr.image_count], NULL);
 277         }
 278         for_lookup_table_entry(dest_wim->lookup_table, lte_rollback_export,
 279                                dest_wim->lookup_table);
 280         return ret;
 281 }