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

   1 /*
   2  * split.c
   3  *
   4  * Split a WIM file into parts.
   5  */
   6
   7 /*
   8  * Copyright (C) 2012, 2013 Eric Biggers
   9  *
  10  * This file is part of wimlib, a library for working with WIM files.
  11  *
  12  * wimlib is free software; you can redistribute it and/or modify it under the
  13  * terms of the GNU General Public License as published by the Free
  14  * Software Foundation; either version 3 of the License, or (at your option)
  15  * any later version.
  16  *
  17  * wimlib is distributed in the hope that it will be useful, but WITHOUT ANY
  18  * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
  19  * A PARTICULAR PURPOSE. See the GNU General Public License for more
  20  * details.
  21  *
  22  * You should have received a copy of the GNU General Public License
  23  * along with wimlib; if not, see http://www.gnu.org/licenses/.
  24  */
  25
  26 #include "wimlib_internal.h"
  27 #include "lookup_table.h"
  28 #include "xml.h"
  29 #include "buffer_io.h"
  30
  31 struct split_args {
  32         WIMStruct *w;
  33         tchar *swm_base_name;
  34         size_t swm_base_name_len;
  35         const tchar *swm_suffix;
  36         struct list_head lte_list;
  37         int cur_part_number;
  38         int write_flags;
  39         long size_remaining;
  40         size_t part_size;
  41         wimlib_progress_func_t progress_func;
  42         union wimlib_progress_info progress;
  43 };
  44
  45 static int
  46 finish_swm(WIMStruct *w, struct list_head *lte_list,
  47            int write_flags, wimlib_progress_func_t progress_func)
  48 {
  49         off_t lookup_table_offset = ftello(w->out_fp);
  50         int ret;
  51         struct wim_lookup_table_entry *lte;
  52
  53         list_for_each_entry(lte, lte_list, staging_list) {
  54                 ret = write_lookup_table_entry(lte, w->out_fp);
  55                 if (ret != 0)
  56                         return ret;
  57         }
  58
  59         off_t xml_data_offset = ftello(w->out_fp);
  60
  61         if (lookup_table_offset == -1 || xml_data_offset == -1)
  62                 return WIMLIB_ERR_WRITE;
  63         w->hdr.lookup_table_res_entry.offset = lookup_table_offset;
  64         w->hdr.lookup_table_res_entry.size =
  65                                 xml_data_offset - lookup_table_offset;
  66         w->hdr.lookup_table_res_entry.original_size =
  67                                 xml_data_offset - lookup_table_offset;
  68         w->hdr.lookup_table_res_entry.flags = WIM_RESHDR_FLAG_METADATA;
  69         return finish_write(w, WIMLIB_ALL_IMAGES,
  70                             write_flags | WIMLIB_WRITE_FLAG_NO_LOOKUP_TABLE,
  71                             progress_func);
  72 }
  73
  74 static int
  75 copy_resource_to_swm(struct wim_lookup_table_entry *lte, void *__args)
  76 {
  77         struct split_args *args = (struct split_args*)__args;
  78         WIMStruct *w = args->w;
  79         int ret;
  80
  81         /* metadata resources were already written. */
  82         if (lte->resource_entry.flags & WIM_RESHDR_FLAG_METADATA)
  83                 return 0;
  84
  85         if (args->size_remaining < 0 ||
  86                         (u64)args->size_remaining < lte->resource_entry.size) {
  87
  88                 /* No space for this resource.  Finish the previous swm and
  89                  * start a new one. */
  90
  91                 ret = finish_swm(w, &args->lte_list, args->write_flags,
  92                                  args->progress_func);
  93                 if (ret != 0)
  94                         return ret;
  95
  96                 if (args->progress_func) {
  97                         args->progress_func(WIMLIB_PROGRESS_MSG_SPLIT_END_PART,
  98                                             &args->progress);
  99                 }
 100
 101                 INIT_LIST_HEAD(&args->lte_list);
 102                 args->cur_part_number++;
 103
 104                 tsprintf(args->swm_base_name + args->swm_base_name_len, T("%d%"TS),
 105                          args->cur_part_number, args->swm_suffix);
 106
 107                 w->hdr.part_number = args->cur_part_number;
 108
 109                 if (args->progress_func) {
 110                         args->progress.split.cur_part_number = args->cur_part_number;
 111                         args->progress_func(WIMLIB_PROGRESS_MSG_SPLIT_BEGIN_PART,
 112                                             &args->progress);
 113                 }
 114
 115                 ret = begin_write(w, args->swm_base_name, args->write_flags);
 116                 if (ret != 0)
 117                         return ret;
 118                 args->size_remaining = args->part_size;
 119         }
 120         args->size_remaining -= lte->resource_entry.size;
 121         args->progress.split.completed_bytes += lte->resource_entry.size;
 122         list_add_tail(&lte->staging_list, &args->lte_list);
 123         return copy_resource(lte, w);
 124 }
 125
 126 /* Splits the WIM file @w into multiple parts prefixed by @swm_name with size at
 127  * most @part_size bytes. */
 128 WIMLIBAPI int
 129 wimlib_split(WIMStruct *w, const tchar *swm_name,
 130              size_t part_size, int write_flags,
 131              wimlib_progress_func_t progress_func)
 132 {
 133         int ret;
 134         struct wim_header hdr_save;
 135         struct split_args args;
 136         const tchar *swm_suffix;
 137         size_t swm_name_len;
 138         size_t swm_base_name_len;
 139
 140         if (!swm_name || part_size == 0)
 141                 return WIMLIB_ERR_INVALID_PARAM;
 142
 143         if (w->hdr.total_parts != 1)
 144                 return WIMLIB_ERR_SPLIT_UNSUPPORTED;
 145
 146         write_flags &= WIMLIB_WRITE_MASK_PUBLIC;
 147
 148         swm_name_len = tstrlen(swm_name);
 149         tchar swm_base_name[swm_name_len + 20];
 150
 151         memcpy(&hdr_save, &w->hdr, sizeof(struct wim_header));
 152         w->hdr.flags |= WIM_HDR_FLAG_SPANNED;
 153         w->hdr.boot_idx = 0;
 154         randomize_byte_array(w->hdr.guid, WIM_GID_LEN);
 155         ret = begin_write(w, swm_name, write_flags);
 156         if (ret != 0)
 157                 goto out;
 158
 159         tmemcpy(swm_base_name, swm_name, swm_name_len + 1);
 160
 161         swm_suffix = tstrchr(swm_name, T('.'));
 162         if (swm_suffix) {
 163                 swm_base_name_len = swm_suffix - swm_name;
 164         } else {
 165                 swm_base_name_len = swm_name_len;
 166                 swm_base_name[ARRAY_LEN(swm_base_name) - 1] = T('\0');
 167                 swm_suffix = &swm_base_name[ARRAY_LEN(swm_base_name) - 1];
 168         }
 169
 170         args.w                              = w;
 171         args.swm_base_name                  = swm_base_name;
 172         args.swm_base_name_len              = swm_base_name_len;
 173         args.swm_suffix                     = swm_suffix;
 174         INIT_LIST_HEAD(&args.lte_list);
 175         args.cur_part_number                = 1;
 176         args.write_flags                    = write_flags;
 177         args.size_remaining                 = part_size;
 178         args.part_size                      = part_size;
 179         args.progress_func                  = progress_func;
 180         args.progress.split.total_bytes     = lookup_table_total_stream_size(w->lookup_table);
 181         args.progress.split.cur_part_number = 1;
 182         args.progress.split.completed_bytes = 0;
 183         args.progress.split.part_name       = swm_base_name;
 184
 185         if (progress_func) {
 186                 progress_func(WIMLIB_PROGRESS_MSG_SPLIT_BEGIN_PART,
 187                               &args.progress);
 188         }
 189
 190         for (int i = 0; i < w->hdr.image_count; i++) {
 191                 struct wim_lookup_table_entry *metadata_lte;
 192                 metadata_lte = w->image_metadata[i].metadata_lte;
 193                 ret = copy_resource(metadata_lte, w);
 194                 if (ret != 0)
 195                         goto out;
 196                 args.size_remaining -= metadata_lte->resource_entry.size;
 197                 args.progress.split.completed_bytes += metadata_lte->resource_entry.size;
 198                 /* Careful: The metadata lookup table entries must be added in
 199                  * order of the images. */
 200                 list_add_tail(&metadata_lte->staging_list, &args.lte_list);
 201         }
 202
 203         ret = for_lookup_table_entry(w->lookup_table,
 204                                      copy_resource_to_swm, &args);
 205         if (ret != 0)
 206                 goto out;
 207
 208         ret = finish_swm(w, &args.lte_list, write_flags, progress_func);
 209         if (ret != 0)
 210                 goto out;
 211
 212         if (progress_func) {
 213                 progress_func(WIMLIB_PROGRESS_MSG_SPLIT_END_PART,
 214                               &args.progress);
 215         }
 216
 217         /* The swms are all ready now, except the total_parts and part_number
 218          * fields in their headers are wrong (since we don't know the total
 219          * parts until they are all written).  Fix them. */
 220         int total_parts = args.cur_part_number;
 221         for (int i = 1; i <= total_parts; i++) {
 222                 const tchar *part_name;
 223                 if (i == 1) {
 224                         part_name = swm_name;
 225                 } else {
 226                         tsprintf(swm_base_name + swm_base_name_len, T("%d%"TS),
 227                                  i, swm_suffix);
 228                         part_name = swm_base_name;
 229                 }
 230
 231                 FILE *fp = tfopen(part_name, T("r+b"));
 232                 if (!fp) {
 233                         ERROR_WITH_ERRNO("Failed to open `%"TS"'", part_name);
 234                         ret = WIMLIB_ERR_OPEN;
 235                         goto out;
 236                 }
 237                 u8 buf[4];
 238                 put_u16(&buf[0], i);
 239                 put_u16(&buf[2], total_parts);
 240
 241                 if (fseek(fp, 40, SEEK_SET) != 0 ||
 242                     fwrite(buf, 1, sizeof(buf), fp) != sizeof(buf) ||
 243                     fclose(fp) != 0)
 244                 {
 245                         ERROR_WITH_ERRNO("Error overwriting header of `%"TS"'",
 246                                          part_name);
 247                         ret = WIMLIB_ERR_WRITE;
 248                         break;
 249                 }
 250         }
 251 out:
 252         close_wim_writable(w);
 253         memcpy(&w->hdr, &hdr_save, sizeof(struct wim_header));
 254         return ret;
 255 }