4 * Support for writing WIM files; write a WIM file, overwrite a WIM file, write
5 * compressed file resources, etc.
9 * Copyright (C) 2010 Carl Thijssen
10 * Copyright (C) 2012 Eric Biggers
12 * This file is part of wimlib, a library for working with WIM files.
14 * wimlib is free software; you can redistribute it and/or modify it under the
15 * terms of the GNU General Public License as published by the Free
16 * Software Foundation; either version 3 of the License, or (at your option)
19 * wimlib is distributed in the hope that it will be useful, but WITHOUT ANY
20 * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
21 * A PARTICULAR PURPOSE. See the GNU General Public License for more
24 * You should have received a copy of the GNU General Public License
25 * along with wimlib; if not, see http://www.gnu.org/licenses/.
28 #include "wimlib_internal.h"
31 #include "lookup_table.h"
37 #ifdef ENABLE_MULTITHREADED_COMPRESSION
38 #include <semaphore.h>
45 #include <ntfs-3g/attrib.h>
46 #include <ntfs-3g/inode.h>
47 #include <ntfs-3g/dir.h>
57 static int do_fflush(FILE *fp)
61 ERROR_WITH_ERRNO("Failed to flush data to output WIM file");
62 return WIMLIB_ERR_WRITE;
67 static int fflush_and_ftruncate(FILE *fp, off_t size)
74 ret = ftruncate(fileno(fp), size);
76 ERROR_WITH_ERRNO("Failed to truncate output WIM file to "
77 "%"PRIu64" bytes", size);
78 return WIMLIB_ERR_WRITE;
83 /* Chunk table that's located at the beginning of each compressed resource in
84 * the WIM. (This is not the on-disk format; the on-disk format just has an
85 * array of offsets.) */
89 u64 original_resource_size;
90 u64 bytes_per_chunk_entry;
98 * Allocates and initializes a chunk table, and reserves space for it in the
102 begin_wim_resource_chunk_tab(const struct lookup_table_entry *lte,
105 struct chunk_table **chunk_tab_ret)
107 u64 size = wim_resource_size(lte);
108 u64 num_chunks = (size + WIM_CHUNK_SIZE - 1) / WIM_CHUNK_SIZE;
109 size_t alloc_size = sizeof(struct chunk_table) + num_chunks * sizeof(u64);
110 struct chunk_table *chunk_tab = CALLOC(1, alloc_size);
114 ERROR("Failed to allocate chunk table for %"PRIu64" byte "
116 ret = WIMLIB_ERR_NOMEM;
119 chunk_tab->file_offset = file_offset;
120 chunk_tab->num_chunks = num_chunks;
121 chunk_tab->original_resource_size = size;
122 chunk_tab->bytes_per_chunk_entry = (size >= (1ULL << 32)) ? 8 : 4;
123 chunk_tab->table_disk_size = chunk_tab->bytes_per_chunk_entry *
125 chunk_tab->cur_offset = 0;
126 chunk_tab->cur_offset_p = chunk_tab->offsets;
128 if (fwrite(chunk_tab, 1, chunk_tab->table_disk_size, out_fp) !=
129 chunk_tab->table_disk_size) {
130 ERROR_WITH_ERRNO("Failed to write chunk table in compressed "
132 ret = WIMLIB_ERR_WRITE;
138 *chunk_tab_ret = chunk_tab;
143 * Pointer to function to compresses a chunk of a WIM resource.
145 * @chunk: Uncompressed data of the chunk.
146 * @chunk_size: Size of the uncompressed chunk in bytes.
147 * @compressed_chunk: Pointer to output buffer of size at least
148 * (@chunk_size - 1) bytes.
149 * @compressed_chunk_len_ret: Pointer to an unsigned int into which the size
150 * of the compressed chunk will be
153 * Returns zero if compressed succeeded, and nonzero if the chunk could not be
154 * compressed to any smaller than @chunk_size. This function cannot fail for
157 typedef int (*compress_func_t)(const void *, unsigned, void *, unsigned *);
159 compress_func_t get_compress_func(int out_ctype)
161 if (out_ctype == WIM_COMPRESSION_TYPE_LZX)
164 return xpress_compress;
168 * Writes a chunk of a WIM resource to an output file.
170 * @chunk: Uncompressed data of the chunk.
171 * @chunk_size: Size of the chunk (<= WIM_CHUNK_SIZE)
172 * @out_fp: FILE * to write tho chunk to.
173 * @out_ctype: Compression type to use when writing the chunk (ignored if no
174 * chunk table provided)
175 * @chunk_tab: Pointer to chunk table being created. It is updated with the
176 * offset of the chunk we write.
178 * Returns 0 on success; nonzero on failure.
180 static int write_wim_resource_chunk(const u8 chunk[], unsigned chunk_size,
181 FILE *out_fp, compress_func_t compress,
182 struct chunk_table *chunk_tab)
185 unsigned out_chunk_size;
187 u8 *compressed_chunk = alloca(chunk_size);
190 ret = compress(chunk, chunk_size, compressed_chunk,
193 out_chunk = compressed_chunk;
196 out_chunk_size = chunk_size;
198 *chunk_tab->cur_offset_p++ = chunk_tab->cur_offset;
199 chunk_tab->cur_offset += out_chunk_size;
202 out_chunk_size = chunk_size;
204 if (fwrite(out_chunk, 1, out_chunk_size, out_fp) != out_chunk_size) {
205 ERROR_WITH_ERRNO("Failed to write WIM resource chunk");
206 return WIMLIB_ERR_WRITE;
212 * Finishes a WIM chunk tale and writes it to the output file at the correct
215 * The final size of the full compressed resource is returned in the
216 * @compressed_size_p.
219 finish_wim_resource_chunk_tab(struct chunk_table *chunk_tab,
220 FILE *out_fp, u64 *compressed_size_p)
222 size_t bytes_written;
223 if (fseeko(out_fp, chunk_tab->file_offset, SEEK_SET) != 0) {
224 ERROR_WITH_ERRNO("Failed to seek to byte %"PRIu64" of output "
225 "WIM file", chunk_tab->file_offset);
226 return WIMLIB_ERR_WRITE;
229 if (chunk_tab->bytes_per_chunk_entry == 8) {
230 array_cpu_to_le64(chunk_tab->offsets, chunk_tab->num_chunks);
232 for (u64 i = 0; i < chunk_tab->num_chunks; i++)
233 ((u32*)chunk_tab->offsets)[i] =
234 cpu_to_le32(chunk_tab->offsets[i]);
236 bytes_written = fwrite((u8*)chunk_tab->offsets +
237 chunk_tab->bytes_per_chunk_entry,
238 1, chunk_tab->table_disk_size, out_fp);
239 if (bytes_written != chunk_tab->table_disk_size) {
240 ERROR_WITH_ERRNO("Failed to write chunk table in compressed "
242 return WIMLIB_ERR_WRITE;
244 if (fseeko(out_fp, 0, SEEK_END) != 0) {
245 ERROR_WITH_ERRNO("Failed to seek to end of output WIM file");
246 return WIMLIB_ERR_WRITE;
248 *compressed_size_p = chunk_tab->cur_offset + chunk_tab->table_disk_size;
252 /* Prepare for multiple reads to a resource by caching a FILE * or NTFS
253 * attribute pointer in the lookup table entry. */
254 static int prepare_resource_for_read(struct lookup_table_entry *lte
257 , ntfs_inode **ni_ret
261 if (lte->resource_location == RESOURCE_IN_FILE_ON_DISK
262 && !lte->file_on_disk_fp)
264 wimlib_assert(lte->file_on_disk);
265 lte->file_on_disk_fp = fopen(lte->file_on_disk, "rb");
266 if (!lte->file_on_disk_fp) {
267 ERROR_WITH_ERRNO("Failed to open the file `%s' for "
268 "reading", lte->file_on_disk);
269 return WIMLIB_ERR_OPEN;
273 else if (lte->resource_location == RESOURCE_IN_NTFS_VOLUME
276 struct ntfs_location *loc = lte->ntfs_loc;
279 ni = ntfs_pathname_to_inode(*loc->ntfs_vol_p, NULL, loc->path_utf8);
281 ERROR_WITH_ERRNO("Failed to open inode `%s' in NTFS "
282 "volume", loc->path_utf8);
283 return WIMLIB_ERR_NTFS_3G;
285 lte->attr = ntfs_attr_open(ni,
286 loc->is_reparse_point ? AT_REPARSE_POINT : AT_DATA,
287 (ntfschar*)loc->stream_name_utf16,
288 loc->stream_name_utf16_num_chars);
290 ERROR_WITH_ERRNO("Failed to open attribute of `%s' in "
291 "NTFS volume", loc->path_utf8);
292 ntfs_inode_close(ni);
293 return WIMLIB_ERR_NTFS_3G;
301 /* Undo prepare_resource_for_read() by closing the cached FILE * or NTFS
303 static void end_wim_resource_read(struct lookup_table_entry *lte
309 if (lte->resource_location == RESOURCE_IN_FILE_ON_DISK
310 && lte->file_on_disk_fp) {
311 fclose(lte->file_on_disk_fp);
312 lte->file_on_disk_fp = NULL;
315 else if (lte->resource_location == RESOURCE_IN_NTFS_VOLUME) {
317 ntfs_attr_close(lte->attr);
321 ntfs_inode_close(ni);
327 * Writes a WIM resource to a FILE * opened for writing. The resource may be
328 * written uncompressed or compressed depending on the @out_ctype parameter.
330 * If by chance the resource compresses to more than the original size (this may
331 * happen with random data or files than are pre-compressed), the resource is
332 * instead written uncompressed (and this is reflected in the @out_res_entry by
333 * removing the WIM_RESHDR_FLAG_COMPRESSED flag).
335 * @lte: The lookup table entry for the WIM resource.
336 * @out_fp: The FILE * to write the resource to.
337 * @out_ctype: The compression type of the resource to write. Note: if this is
338 * the same as the compression type of the WIM resource we
339 * need to read, we simply copy the data (i.e. we do not
340 * uncompress it, then compress it again).
341 * @out_res_entry: If non-NULL, a resource entry that is filled in with the
342 * offset, original size, compressed size, and compression flag
343 * of the output resource.
345 * Returns 0 on success; nonzero on failure.
347 int write_wim_resource(struct lookup_table_entry *lte,
348 FILE *out_fp, int out_ctype,
349 struct resource_entry *out_res_entry,
354 u64 old_compressed_size;
355 u64 new_compressed_size;
358 struct chunk_table *chunk_tab = NULL;
361 compress_func_t compress;
363 ntfs_inode *ni = NULL;
368 /* Original size of the resource */
369 original_size = wim_resource_size(lte);
371 /* Compressed size of the resource (as it exists now) */
372 old_compressed_size = wim_resource_compressed_size(lte);
374 /* Current offset in output file */
375 file_offset = ftello(out_fp);
376 if (file_offset == -1) {
377 ERROR_WITH_ERRNO("Failed to get offset in output "
379 return WIMLIB_ERR_WRITE;
382 /* Are the compression types the same? If so, do a raw copy (copy
383 * without decompressing and recompressing the data). */
384 raw = (wim_resource_compression_type(lte) == out_ctype
385 && out_ctype != WIM_COMPRESSION_TYPE_NONE);
388 flags |= WIMLIB_RESOURCE_FLAG_RAW;
389 bytes_remaining = old_compressed_size;
391 flags &= ~WIMLIB_RESOURCE_FLAG_RAW;
392 bytes_remaining = original_size;
395 /* Empty resource; nothing needs to be done, so just return success. */
396 if (bytes_remaining == 0)
399 /* Buffer for reading chunks for the resource */
400 u8 buf[min(WIM_CHUNK_SIZE, bytes_remaining)];
402 /* If we are writing a compressed resource and not doing a raw copy, we
403 * need to initialize the chunk table */
404 if (out_ctype != WIM_COMPRESSION_TYPE_NONE && !raw) {
405 ret = begin_wim_resource_chunk_tab(lte, out_fp, file_offset,
411 /* If the WIM resource is in an external file, open a FILE * to it so we
412 * don't have to open a temporary one in read_wim_resource() for each
415 ret = prepare_resource_for_read(lte, &ni);
417 ret = prepare_resource_for_read(lte);
422 /* If we aren't doing a raw copy, we will compute the SHA1 message
423 * digest of the resource as we read it, and verify it's the same as the
424 * hash given in the lookup table entry once we've finished reading the
429 compress = get_compress_func(out_ctype);
433 /* While there are still bytes remaining in the WIM resource, read a
434 * chunk of the resource, update SHA1, then write that chunk using the
435 * desired compression type. */
437 u64 to_read = min(bytes_remaining, WIM_CHUNK_SIZE);
438 ret = read_wim_resource(lte, buf, to_read, offset, flags);
442 sha1_update(&ctx, buf, to_read);
443 ret = write_wim_resource_chunk(buf, to_read, out_fp,
444 compress, chunk_tab);
447 bytes_remaining -= to_read;
449 } while (bytes_remaining);
451 /* Raw copy: The new compressed size is the same as the old compressed
454 * Using WIM_COMPRESSION_TYPE_NONE: The new compressed size is the
457 * Using a different compression type: Call
458 * finish_wim_resource_chunk_tab() and it will provide the new
462 new_compressed_size = old_compressed_size;
464 if (out_ctype == WIM_COMPRESSION_TYPE_NONE)
465 new_compressed_size = original_size;
467 ret = finish_wim_resource_chunk_tab(chunk_tab, out_fp,
468 &new_compressed_size);
474 /* Verify SHA1 message digest of the resource, unless we are doing a raw
475 * write (in which case we never even saw the uncompressed data). Or,
476 * if the hash we had before is all 0's, just re-set it to be the new
479 u8 md[SHA1_HASH_SIZE];
480 sha1_final(md, &ctx);
481 if (is_zero_hash(lte->hash)) {
482 copy_hash(lte->hash, md);
483 } else if (!hashes_equal(md, lte->hash)) {
484 ERROR("WIM resource has incorrect hash!");
485 if (lte->resource_location == RESOURCE_IN_FILE_ON_DISK) {
486 ERROR("We were reading it from `%s'; maybe it changed "
487 "while we were reading it.",
490 ret = WIMLIB_ERR_INVALID_RESOURCE_HASH;
495 if (!raw && new_compressed_size >= original_size &&
496 out_ctype != WIM_COMPRESSION_TYPE_NONE)
498 /* Oops! We compressed the resource to larger than the original
499 * size. Write the resource uncompressed instead. */
500 if (fseeko(out_fp, file_offset, SEEK_SET) != 0) {
501 ERROR_WITH_ERRNO("Failed to seek to byte %"PRIu64" "
502 "of output WIM file", file_offset);
503 ret = WIMLIB_ERR_WRITE;
506 ret = write_wim_resource(lte, out_fp, WIM_COMPRESSION_TYPE_NONE,
507 out_res_entry, flags);
511 ret = fflush_and_ftruncate(out_fp, file_offset + out_res_entry->size);
516 out_res_entry->size = new_compressed_size;
517 out_res_entry->original_size = original_size;
518 out_res_entry->offset = file_offset;
519 out_res_entry->flags = lte->resource_entry.flags
520 & ~WIM_RESHDR_FLAG_COMPRESSED;
521 if (out_ctype != WIM_COMPRESSION_TYPE_NONE)
522 out_res_entry->flags |= WIM_RESHDR_FLAG_COMPRESSED;
528 end_wim_resource_read(lte, ni);
530 end_wim_resource_read(lte);
537 #ifdef ENABLE_MULTITHREADED_COMPRESSION
538 struct shared_queue {
541 pthread_mutex_t lock;
548 static int shared_queue_init(struct shared_queue *q, unsigned size)
550 q->array = CALLOC(sizeof(q->array[0]), size);
552 return WIMLIB_ERR_NOMEM;
554 sem_init(&q->filled_slots, 0, 0);
555 sem_init(&q->empty_slots, 0, size);
556 pthread_mutex_init(&q->lock, NULL);
563 static void shared_queue_destroy(struct shared_queue *q)
565 sem_destroy(&q->filled_slots);
566 sem_destroy(&q->empty_slots);
567 pthread_mutex_destroy(&q->lock);
571 static void shared_queue_put(struct shared_queue *q, void *obj)
573 sem_wait(&q->empty_slots);
574 pthread_mutex_lock(&q->lock);
576 q->back = (q->back + 1) % q->size;
577 q->array[q->back] = obj;
579 sem_post(&q->filled_slots);
580 pthread_mutex_unlock(&q->lock);
583 static void *shared_queue_get(struct shared_queue *q)
585 sem_wait(&q->filled_slots);
586 pthread_mutex_lock(&q->lock);
588 void *obj = q->array[q->front];
589 q->array[q->front] = NULL;
590 q->front = (q->front + 1) % q->size;
592 sem_post(&q->empty_slots);
593 pthread_mutex_unlock(&q->lock);
597 struct compressor_thread_params {
598 struct shared_queue *res_to_compress_queue;
599 struct shared_queue *compressed_res_queue;
600 compress_func_t compress;
603 #define MAX_CHUNKS_PER_MSG 2
606 struct lookup_table_entry *lte;
607 u8 *uncompressed_chunks[MAX_CHUNKS_PER_MSG];
608 u8 *out_compressed_chunks[MAX_CHUNKS_PER_MSG];
609 u8 *compressed_chunks[MAX_CHUNKS_PER_MSG];
610 unsigned uncompressed_chunk_sizes[MAX_CHUNKS_PER_MSG];
611 unsigned compressed_chunk_sizes[MAX_CHUNKS_PER_MSG];
613 struct list_head list;
618 static void compress_chunks(struct message *msg, compress_func_t compress)
620 for (unsigned i = 0; i < msg->num_chunks; i++) {
621 DEBUG2("compress chunk %u of %u", i, msg->num_chunks);
622 int ret = compress(msg->uncompressed_chunks[i],
623 msg->uncompressed_chunk_sizes[i],
624 msg->compressed_chunks[i],
625 &msg->compressed_chunk_sizes[i]);
627 msg->out_compressed_chunks[i] = msg->compressed_chunks[i];
629 msg->out_compressed_chunks[i] = msg->uncompressed_chunks[i];
630 msg->compressed_chunk_sizes[i] = msg->uncompressed_chunk_sizes[i];
635 static void *compressor_thread_proc(void *arg)
637 struct compressor_thread_params *params = arg;
638 struct shared_queue *res_to_compress_queue = params->res_to_compress_queue;
639 struct shared_queue *compressed_res_queue = params->compressed_res_queue;
640 compress_func_t compress = params->compress;
643 DEBUG("Compressor thread ready");
644 while ((msg = shared_queue_get(res_to_compress_queue)) != NULL) {
645 compress_chunks(msg, compress);
646 shared_queue_put(compressed_res_queue, msg);
648 DEBUG("Compressor thread terminating");
652 static void show_stream_write_progress(u64 *cur_size, u64 *next_size,
653 u64 total_size, u64 one_percent,
654 unsigned *cur_percent,
655 const struct lookup_table_entry *cur_lte)
657 if (*cur_size >= *next_size) {
658 printf("\r%"PRIu64" MiB of %"PRIu64" MiB "
659 "(uncompressed) written (%u%% done)",
661 total_size >> 20, *cur_percent);
663 *next_size += one_percent;
666 *cur_size += wim_resource_size(cur_lte);
669 static void finish_stream_write_progress(u64 total_size)
671 printf("\r%"PRIu64" MiB of %"PRIu64" MiB "
672 "(uncompressed) written (100%% done)\n",
673 total_size >> 20, total_size >> 20);
677 static int write_stream_list_serial(struct list_head *stream_list,
678 FILE *out_fp, int out_ctype,
679 int write_flags, u64 total_size)
681 struct lookup_table_entry *lte;
684 u64 one_percent = total_size / 100;
687 unsigned cur_percent = 0;
689 list_for_each_entry(lte, stream_list, staging_list) {
690 if (write_flags & WIMLIB_WRITE_FLAG_SHOW_PROGRESS) {
691 show_stream_write_progress(&cur_size, &next_size,
692 total_size, one_percent,
695 ret = write_wim_resource(lte, out_fp, out_ctype,
696 <e->output_resource_entry, 0);
700 if (write_flags & WIMLIB_WRITE_FLAG_SHOW_PROGRESS)
701 finish_stream_write_progress(total_size);
705 #ifdef ENABLE_MULTITHREADED_COMPRESSION
706 static int write_wim_chunks(struct message *msg, FILE *out_fp,
707 struct chunk_table *chunk_tab)
709 for (unsigned i = 0; i < msg->num_chunks; i++) {
710 unsigned chunk_csize = msg->compressed_chunk_sizes[i];
712 DEBUG2("Write wim chunk %u of %u (csize = %u)",
713 i, msg->num_chunks, chunk_csize);
715 if (fwrite(msg->out_compressed_chunks[i], 1, chunk_csize, out_fp)
718 ERROR_WITH_ERRNO("Failed to write WIM chunk");
719 return WIMLIB_ERR_WRITE;
722 *chunk_tab->cur_offset_p++ = chunk_tab->cur_offset;
723 chunk_tab->cur_offset += chunk_csize;
729 * This function is executed by the main thread when the resources are being
730 * compressed in parallel. The main thread is in change of all reading of the
731 * uncompressed data and writing of the compressed data. The compressor threads
732 * *only* do compression from/to in-memory buffers.
734 * Each unit of work given to a compressor thread is up to MAX_CHUNKS_PER_MSG
735 * chunks of compressed data to compress, represented in a `struct message'.
736 * Each message is passed from the main thread to a worker thread through the
737 * res_to_compress_queue, and it is passed back through the
738 * compressed_res_queue.
740 static int main_writer_thread_proc(struct list_head *stream_list,
743 struct shared_queue *res_to_compress_queue,
744 struct shared_queue *compressed_res_queue,
752 struct message msgs[queue_size];
755 // Initially, all the messages are available to use.
756 LIST_HEAD(available_msgs);
757 for (size_t i = 0; i < ARRAY_LEN(msgs); i++)
758 list_add(&msgs[i].list, &available_msgs);
760 // outstanding_resources is the list of resources that currently have
761 // had chunks sent off for compression.
763 // The first stream in outstanding_resources is the stream that is
764 // currently being written (cur_lte).
766 // The last stream in outstanding_resources is the stream that is
767 // currently being read and chunks fed to the compressor threads
770 // Depending on the number of threads and the sizes of the resource,
771 // the outstanding streams list may contain streams between cur_lte and
772 // next_lte that have all their chunks compressed or being compressed,
773 // but haven't been written yet.
775 LIST_HEAD(outstanding_resources);
776 struct list_head *next_resource = stream_list->next;
777 struct lookup_table_entry *next_lte = container_of(next_resource,
778 struct lookup_table_entry,
780 next_resource = next_resource->next;
782 u64 next_num_chunks = wim_resource_chunks(next_lte);
783 INIT_LIST_HEAD(&next_lte->msg_list);
784 list_add_tail(&next_lte->staging_list, &outstanding_resources);
786 // As in write_wim_resource(), each resource we read is checksummed.
787 SHA_CTX next_sha_ctx;
788 sha1_init(&next_sha_ctx);
789 u8 next_hash[SHA1_HASH_SIZE];
791 // Resources that don't need any chunks compressed are added to this
792 // list and written directly by the main thread.
793 LIST_HEAD(my_resources);
795 struct lookup_table_entry *cur_lte = next_lte;
796 struct chunk_table *cur_chunk_tab = NULL;
797 struct lookup_table_entry *lte;
800 u64 one_percent = total_size / 100;
803 unsigned cur_percent = 0;
806 ntfs_inode *ni = NULL;
810 ret = prepare_resource_for_read(next_lte, &ni);
812 ret = prepare_resource_for_read(next_lte);
817 DEBUG("Initializing buffers for uncompressed "
818 "and compressed data (%zu bytes needed)",
819 queue_size * MAX_CHUNKS_PER_MSG * WIM_CHUNK_SIZE * 2);
821 // Pre-allocate all the buffers that will be needed to do the chunk
823 for (size_t i = 0; i < ARRAY_LEN(msgs); i++) {
824 for (size_t j = 0; j < MAX_CHUNKS_PER_MSG; j++) {
825 msgs[i].compressed_chunks[j] = MALLOC(WIM_CHUNK_SIZE);
826 msgs[i].uncompressed_chunks[j] = MALLOC(WIM_CHUNK_SIZE);
827 if (msgs[i].compressed_chunks[j] == NULL ||
828 msgs[i].uncompressed_chunks[j] == NULL)
830 ERROR("Could not allocate enough memory for "
831 "multi-threaded compression");
832 ret = WIMLIB_ERR_NOMEM;
838 // This loop is executed until all resources have been written, except
839 // possibly a few that have been added to the @my_resources list for
842 // Send chunks to the compressor threads until either (a) there
843 // are no more messages available since they were all sent off,
844 // or (b) there are no more resources that need to be
846 while (!list_empty(&available_msgs) && next_lte != NULL) {
848 // Get a message from the available messages
850 msg = container_of(available_msgs.next,
854 // ... and delete it from the available messages
856 list_del(&msg->list);
858 // Initialize the message with the chunks to
860 msg->num_chunks = min(next_num_chunks - next_chunk,
863 msg->complete = false;
864 msg->begin_chunk = next_chunk;
866 unsigned size = WIM_CHUNK_SIZE;
867 for (unsigned i = 0; i < msg->num_chunks; i++) {
869 // Read chunk @next_chunk of the stream into the
870 // message so that a compressor thread can
873 if (next_chunk == next_num_chunks - 1 &&
874 wim_resource_size(next_lte) % WIM_CHUNK_SIZE != 0)
876 size = wim_resource_size(next_lte) % WIM_CHUNK_SIZE;
880 DEBUG2("Read resource (size=%u, offset=%zu)",
881 size, next_chunk * WIM_CHUNK_SIZE);
883 msg->uncompressed_chunk_sizes[i] = size;
885 ret = read_wim_resource(next_lte,
886 msg->uncompressed_chunks[i],
888 next_chunk * WIM_CHUNK_SIZE,
892 sha1_update(&next_sha_ctx,
893 msg->uncompressed_chunks[i], size);
897 // Send the compression request
898 list_add_tail(&msg->list, &next_lte->msg_list);
899 shared_queue_put(res_to_compress_queue, msg);
900 DEBUG2("Compression request sent");
902 if (next_chunk != next_num_chunks)
903 // More chunks to send for this resource
906 // Done sending compression requests for a resource!
907 // Check the SHA1 message digest.
908 DEBUG2("Finalize SHA1 md (next_num_chunks=%zu)", next_num_chunks);
909 sha1_final(next_hash, &next_sha_ctx);
910 if (!hashes_equal(next_lte->hash, next_hash)) {
911 ERROR("WIM resource has incorrect hash!");
912 if (next_lte->resource_location == RESOURCE_IN_FILE_ON_DISK) {
913 ERROR("We were reading it from `%s'; maybe it changed "
914 "while we were reading it.",
915 next_lte->file_on_disk);
917 ret = WIMLIB_ERR_INVALID_RESOURCE_HASH;
921 // Advance to the next resource.
923 // If the next resource needs no compression, just write
924 // it with this thread (not now though--- we could be in
925 // the middle of writing another resource.) Keep doing
926 // this until we either get to the end of the resources
927 // list, or we get to a resource that needs compression.
930 if (next_resource == stream_list) {
935 end_wim_resource_read(next_lte, ni);
938 end_wim_resource_read(next_lte);
941 next_lte = container_of(next_resource,
942 struct lookup_table_entry,
944 next_resource = next_resource->next;
945 if ((next_lte->resource_location == RESOURCE_IN_WIM
946 && wimlib_get_compression_type(next_lte->wim) == out_ctype)
947 || wim_resource_size(next_lte) == 0)
949 list_add_tail(&next_lte->staging_list,
952 list_add_tail(&next_lte->staging_list,
953 &outstanding_resources);
955 next_num_chunks = wim_resource_chunks(next_lte);
956 sha1_init(&next_sha_ctx);
957 INIT_LIST_HEAD(&next_lte->msg_list);
959 ret = prepare_resource_for_read(next_lte, &ni);
961 ret = prepare_resource_for_read(next_lte);
965 DEBUG2("Updated next_lte");
971 // If there are no outstanding resources, there are no more
972 // resources that need to be written.
973 if (list_empty(&outstanding_resources)) {
974 DEBUG("No outstanding resources! Done");
979 // Get the next message from the queue and process it.
980 // The message will contain 1 or more data chunks that have been
982 DEBUG2("Waiting for message");
983 msg = shared_queue_get(compressed_res_queue);
984 msg->complete = true;
986 DEBUG2("Received msg (begin_chunk=%"PRIu64")", msg->begin_chunk);
988 list_for_each_entry(msg, &cur_lte->msg_list, list) {
989 DEBUG2("complete=%d", msg->complete);
992 // Is this the next chunk in the current resource? If it's not
993 // (i.e., an earlier chunk in a same or different resource
994 // hasn't been compressed yet), do nothing, and keep this
995 // message around until all earlier chunks are received.
997 // Otherwise, write all the chunks we can.
998 while (!list_empty(&cur_lte->msg_list)
999 && (msg = container_of(cur_lte->msg_list.next,
1003 DEBUG2("Complete msg (begin_chunk=%"PRIu64")", msg->begin_chunk);
1004 if (msg->begin_chunk == 0) {
1005 DEBUG2("Begin chunk tab");
1006 if (write_flags & WIMLIB_WRITE_FLAG_SHOW_PROGRESS) {
1007 show_stream_write_progress(&cur_size,
1015 // This is the first set of chunks. Leave space
1016 // for the chunk table in the output file.
1017 off_t cur_offset = ftello(out_fp);
1018 if (cur_offset == -1) {
1019 ret = WIMLIB_ERR_WRITE;
1022 ret = begin_wim_resource_chunk_tab(cur_lte,
1030 // Write the compressed chunks from the message.
1031 ret = write_wim_chunks(msg, out_fp, cur_chunk_tab);
1035 list_del(&msg->list);
1037 // This message is available to use for different chunks
1039 list_add(&msg->list, &available_msgs);
1041 // Was this the last chunk of the stream? If so,
1043 if (list_empty(&cur_lte->msg_list) &&
1044 msg->begin_chunk + msg->num_chunks == cur_chunk_tab->num_chunks)
1046 DEBUG2("Finish wim chunk tab");
1048 ret = finish_wim_resource_chunk_tab(cur_chunk_tab,
1055 cur_lte->output_resource_entry.size =
1058 cur_lte->output_resource_entry.original_size =
1059 cur_lte->resource_entry.original_size;
1061 cur_lte->output_resource_entry.offset =
1062 cur_chunk_tab->file_offset;
1064 cur_lte->output_resource_entry.flags =
1065 cur_lte->resource_entry.flags |
1066 WIM_RESHDR_FLAG_COMPRESSED;
1068 FREE(cur_chunk_tab);
1069 cur_chunk_tab = NULL;
1071 struct list_head *next = cur_lte->staging_list.next;
1072 list_del(&cur_lte->staging_list);
1074 if (next == &outstanding_resources) {
1075 DEBUG("No more outstanding resources");
1079 cur_lte = container_of(cur_lte->staging_list.next,
1080 struct lookup_table_entry,
1084 // Since we just finished writing a stream,
1085 // write any streams that have been added to the
1086 // my_resources list for direct writing by the
1087 // main thread (e.g. resources that don't need
1088 // to be compressed because the desired
1089 // compression type is the same as the previous
1090 // compression type).
1091 struct lookup_table_entry *tmp;
1092 list_for_each_entry_safe(lte,
1097 if (write_flags & WIMLIB_WRITE_FLAG_SHOW_PROGRESS) {
1098 show_stream_write_progress(&cur_size,
1106 ret = write_wim_resource(lte,
1109 <e->output_resource_entry,
1111 list_del(<e->staging_list);
1121 end_wim_resource_read(cur_lte, ni);
1123 end_wim_resource_read(cur_lte);
1126 list_for_each_entry(lte, &my_resources, staging_list) {
1127 if (write_flags & WIMLIB_WRITE_FLAG_SHOW_PROGRESS) {
1128 show_stream_write_progress(&cur_size,
1135 ret = write_wim_resource(lte, out_fp,
1137 <e->output_resource_entry,
1142 if (write_flags & WIMLIB_WRITE_FLAG_SHOW_PROGRESS)
1143 finish_stream_write_progress(total_size);
1145 size_t num_available_msgs = 0;
1146 struct list_head *cur;
1148 list_for_each(cur, &available_msgs) {
1149 num_available_msgs++;
1152 while (num_available_msgs < ARRAY_LEN(msgs)) {
1153 shared_queue_get(compressed_res_queue);
1154 num_available_msgs++;
1158 DEBUG("Freeing messages");
1160 for (size_t i = 0; i < ARRAY_LEN(msgs); i++) {
1161 for (size_t j = 0; j < MAX_CHUNKS_PER_MSG; j++) {
1162 FREE(msgs[i].compressed_chunks[j]);
1163 FREE(msgs[i].uncompressed_chunks[j]);
1167 if (cur_chunk_tab != NULL)
1168 FREE(cur_chunk_tab);
1173 static const char *get_data_type(int ctype)
1176 case WIM_COMPRESSION_TYPE_NONE:
1177 return "uncompressed";
1178 case WIM_COMPRESSION_TYPE_LZX:
1179 return "LZX-compressed";
1180 case WIM_COMPRESSION_TYPE_XPRESS:
1181 return "XPRESS-compressed";
1185 static int write_stream_list_parallel(struct list_head *stream_list,
1186 FILE *out_fp, int out_ctype,
1187 int write_flags, u64 total_size,
1188 unsigned num_threads)
1191 struct shared_queue res_to_compress_queue;
1192 struct shared_queue compressed_res_queue;
1193 pthread_t *compressor_threads = NULL;
1195 if (num_threads == 0) {
1196 long nthreads = sysconf(_SC_NPROCESSORS_ONLN);
1198 WARNING("Could not determine number of processors! Assuming 1");
1201 num_threads = nthreads;
1205 wimlib_assert(stream_list->next != stream_list);
1207 static const double MESSAGES_PER_THREAD = 2.0;
1208 size_t queue_size = (size_t)(num_threads * MESSAGES_PER_THREAD);
1210 DEBUG("Initializing shared queues (queue_size=%zu)", queue_size);
1212 ret = shared_queue_init(&res_to_compress_queue, queue_size);
1216 ret = shared_queue_init(&compressed_res_queue, queue_size);
1218 goto out_destroy_res_to_compress_queue;
1220 struct compressor_thread_params params;
1221 params.res_to_compress_queue = &res_to_compress_queue;
1222 params.compressed_res_queue = &compressed_res_queue;
1223 params.compress = get_compress_func(out_ctype);
1225 compressor_threads = MALLOC(num_threads * sizeof(pthread_t));
1227 for (unsigned i = 0; i < num_threads; i++) {
1228 DEBUG("pthread_create thread %u", i);
1229 ret = pthread_create(&compressor_threads[i], NULL,
1230 compressor_thread_proc, ¶ms);
1233 ERROR_WITH_ERRNO("Failed to create compressor "
1240 if (write_flags & WIMLIB_WRITE_FLAG_SHOW_PROGRESS) {
1241 printf("Writing %s compressed data using %u threads...\n",
1242 get_data_type(out_ctype), num_threads);
1245 ret = main_writer_thread_proc(stream_list,
1248 &res_to_compress_queue,
1249 &compressed_res_queue,
1255 for (unsigned i = 0; i < num_threads; i++)
1256 shared_queue_put(&res_to_compress_queue, NULL);
1258 for (unsigned i = 0; i < num_threads; i++) {
1259 if (pthread_join(compressor_threads[i], NULL)) {
1260 WARNING("Failed to join compressor thread %u: %s",
1261 i, strerror(errno));
1264 FREE(compressor_threads);
1265 shared_queue_destroy(&compressed_res_queue);
1266 out_destroy_res_to_compress_queue:
1267 shared_queue_destroy(&res_to_compress_queue);
1268 if (ret >= 0 && ret != WIMLIB_ERR_NOMEM)
1271 WARNING("Falling back to single-threaded compression");
1272 return write_stream_list_serial(stream_list, out_fp,
1273 out_ctype, write_flags, total_size);
1278 * Write a list of streams to a WIM (@out_fp) using the compression type
1279 * @out_ctype and up to @num_threads compressor threads.
1281 static int write_stream_list(struct list_head *stream_list, FILE *out_fp,
1282 int out_ctype, int write_flags,
1283 unsigned num_threads)
1285 struct lookup_table_entry *lte;
1286 size_t num_streams = 0;
1288 bool compression_needed = false;
1290 list_for_each_entry(lte, stream_list, staging_list) {
1292 total_size += wim_resource_size(lte);
1293 if (!compression_needed
1294 && out_ctype != WIM_COMPRESSION_TYPE_NONE
1295 && (lte->resource_location != RESOURCE_IN_WIM
1296 || wimlib_get_compression_type(lte->wim) != out_ctype)
1297 && wim_resource_size(lte) != 0)
1298 compression_needed = true;
1301 if (num_streams == 0) {
1302 if (write_flags & WIMLIB_WRITE_FLAG_VERBOSE)
1303 printf("No streams to write\n");
1307 if (write_flags & WIMLIB_WRITE_FLAG_VERBOSE) {
1308 printf("Preparing to write %zu streams "
1309 "(%"PRIu64" total bytes uncompressed)\n",
1310 num_streams, total_size);
1311 printf("Using compression type %s\n",
1312 wimlib_get_compression_type_string(out_ctype));
1315 #ifdef ENABLE_MULTITHREADED_COMPRESSION
1316 if (compression_needed && total_size >= 1000000 && num_threads != 1) {
1317 return write_stream_list_parallel(stream_list, out_fp,
1318 out_ctype, write_flags,
1319 total_size, num_threads);
1324 if (write_flags & WIMLIB_WRITE_FLAG_SHOW_PROGRESS) {
1325 const char *reason = "";
1326 if (!compression_needed)
1327 reason = " (no compression needed)";
1328 printf("Writing %s data using 1 thread%s\n",
1329 get_data_type(out_ctype), reason);
1332 return write_stream_list_serial(stream_list, out_fp,
1333 out_ctype, write_flags,
1339 static int dentry_find_streams_to_write(struct dentry *dentry,
1343 struct list_head *stream_list = w->private;
1344 struct lookup_table_entry *lte;
1345 for (unsigned i = 0; i <= dentry->d_inode->num_ads; i++) {
1346 lte = inode_stream_lte(dentry->d_inode, i, w->lookup_table);
1347 if (lte && ++lte->out_refcnt == 1)
1348 list_add_tail(<e->staging_list, stream_list);
1353 static int find_streams_to_write(WIMStruct *w)
1355 return for_dentry_in_tree(wim_root_dentry(w),
1356 dentry_find_streams_to_write, w);
1359 static int write_wim_streams(WIMStruct *w, int image, int write_flags,
1360 unsigned num_threads)
1363 for_lookup_table_entry(w->lookup_table, lte_zero_out_refcnt, NULL);
1364 LIST_HEAD(stream_list);
1365 w->private = &stream_list;
1366 for_image(w, image, find_streams_to_write);
1367 return write_stream_list(&stream_list, w->out_fp,
1368 wimlib_get_compression_type(w), write_flags,
1373 * Write the lookup table, xml data, and integrity table, then overwrite the WIM
1376 int finish_write(WIMStruct *w, int image, int write_flags)
1379 struct wim_header hdr;
1380 FILE *out = w->out_fp;
1382 /* @hdr will be the header for the new WIM. First copy all the data
1383 * from the header in the WIMStruct; then set all the fields that may
1384 * have changed, including the resource entries, boot index, and image
1386 memcpy(&hdr, &w->hdr, sizeof(struct wim_header));
1388 if (!(write_flags & WIMLIB_WRITE_FLAG_NO_LOOKUP_TABLE)) {
1389 ret = write_lookup_table(w->lookup_table, out, &hdr.lookup_table_res_entry);
1394 ret = write_xml_data(w->wim_info, image, out,
1395 (write_flags & WIMLIB_WRITE_FLAG_NO_LOOKUP_TABLE) ?
1396 wim_info_get_total_bytes(w->wim_info) : 0,
1397 &hdr.xml_res_entry);
1401 if (write_flags & WIMLIB_WRITE_FLAG_CHECK_INTEGRITY) {
1402 off_t old_lookup_table_end;
1403 off_t new_lookup_table_end;
1405 if (write_flags & WIMLIB_WRITE_FLAG_REUSE_INTEGRITY_TABLE) {
1406 old_lookup_table_end = w->hdr.lookup_table_res_entry.offset +
1407 w->hdr.lookup_table_res_entry.size;
1409 old_lookup_table_end = 0;
1411 new_lookup_table_end = hdr.lookup_table_res_entry.offset +
1412 hdr.lookup_table_res_entry.size;
1413 show_progress = ((write_flags & WIMLIB_WRITE_FLAG_SHOW_PROGRESS) != 0);
1415 ret = write_integrity_table(out,
1417 new_lookup_table_end,
1418 old_lookup_table_end,
1423 memset(&hdr.integrity, 0, sizeof(struct resource_entry));
1427 * In the WIM header, there is room for the resource entry for a
1428 * metadata resource labeled as the "boot metadata". This entry should
1429 * be zeroed out if there is no bootable image (boot_idx 0). Otherwise,
1430 * it should be a copy of the resource entry for the image that is
1431 * marked as bootable. This is not well documented...
1433 if (hdr.boot_idx == 0 || !w->image_metadata
1434 || (image != WIM_ALL_IMAGES && image != hdr.boot_idx)) {
1435 memset(&hdr.boot_metadata_res_entry, 0,
1436 sizeof(struct resource_entry));
1438 memcpy(&hdr.boot_metadata_res_entry,
1440 hdr.boot_idx - 1].metadata_lte->output_resource_entry,
1441 sizeof(struct resource_entry));
1444 /* Set image count and boot index correctly for single image writes */
1445 if (image != WIM_ALL_IMAGES) {
1446 hdr.image_count = 1;
1447 if (hdr.boot_idx == image)
1453 if (fseeko(out, 0, SEEK_SET) != 0) {
1454 ret = WIMLIB_ERR_WRITE;
1455 ERROR_WITH_ERRNO("Failed to seek to beginning of WIM "
1456 "to overwrite header");
1460 ret = write_header(&hdr, out);
1464 if (write_flags & WIMLIB_WRITE_FLAG_FSYNC) {
1465 if (fflush(out) != 0
1466 || fsync(fileno(out)) != 0)
1468 ERROR_WITH_ERRNO("Error flushing data to WIM file");
1469 ret = WIMLIB_ERR_WRITE;
1473 if (fclose(out) != 0) {
1474 ERROR_WITH_ERRNO("Failed to close the WIM file");
1476 ret = WIMLIB_ERR_WRITE;
1482 static void close_wim_writable(WIMStruct *w)
1485 if (fclose(w->out_fp) != 0) {
1486 WARNING("Failed to close output WIM: %s",
1493 /* Open file stream and write dummy header for WIM. */
1494 int begin_write(WIMStruct *w, const char *path, int write_flags)
1497 bool need_readable = false;
1499 if (write_flags & WIMLIB_WRITE_FLAG_CHECK_INTEGRITY)
1500 need_readable = true;
1502 ret = open_wim_writable(w, path, trunc, need_readable);
1505 /* Write dummy header. It will be overwritten later. */
1506 return write_header(&w->hdr, w->out_fp);
1509 /* Writes a stand-alone WIM to a file. */
1510 WIMLIBAPI int wimlib_write(WIMStruct *w, const char *path,
1511 int image, int write_flags, unsigned num_threads)
1516 return WIMLIB_ERR_INVALID_PARAM;
1518 write_flags &= WIMLIB_WRITE_MASK_PUBLIC;
1520 if (image != WIM_ALL_IMAGES &&
1521 (image < 1 || image > w->hdr.image_count))
1522 return WIMLIB_ERR_INVALID_IMAGE;
1524 if (w->hdr.total_parts != 1) {
1525 ERROR("Cannot call wimlib_write() on part of a split WIM");
1526 return WIMLIB_ERR_SPLIT_UNSUPPORTED;
1529 if (image == WIM_ALL_IMAGES)
1530 DEBUG("Writing all images to `%s'.", path);
1532 DEBUG("Writing image %d to `%s'.", image, path);
1534 ret = begin_write(w, path, write_flags);
1538 ret = write_wim_streams(w, image, write_flags, num_threads);
1542 if (write_flags & WIMLIB_WRITE_FLAG_SHOW_PROGRESS)
1543 printf("Writing image metadata...\n");
1545 ret = for_image(w, image, write_metadata_resource);
1549 ret = finish_write(w, image, write_flags);
1550 if (ret == 0 && (write_flags & WIMLIB_WRITE_FLAG_SHOW_PROGRESS))
1551 printf("Successfully wrote `%s'\n", path);
1553 close_wim_writable(w);
1557 static int lte_overwrite_prepare(struct lookup_table_entry *lte,
1560 memcpy(<e->output_resource_entry, <e->resource_entry,
1561 sizeof(struct resource_entry));
1562 lte->out_refcnt = 0;
1566 static int check_resource_offset(struct lookup_table_entry *lte, void *arg)
1568 off_t end_offset = *(u64*)arg;
1570 wimlib_assert(lte->out_refcnt <= lte->refcnt);
1571 if (lte->out_refcnt < lte->refcnt) {
1572 if (lte->resource_entry.offset + lte->resource_entry.size > end_offset) {
1573 ERROR("The following resource is after the XML data:");
1574 print_lookup_table_entry(lte);
1575 return WIMLIB_ERR_RESOURCE_ORDER;
1581 static int find_new_streams(struct lookup_table_entry *lte, void *arg)
1583 if (lte->out_refcnt == lte->refcnt)
1584 list_add(<e->staging_list, (struct list_head*)arg);
1586 lte->out_refcnt = lte->refcnt;
1590 static int overwrite_wim_inplace(WIMStruct *w, int write_flags,
1591 unsigned num_threads,
1592 int modified_image_idx)
1595 struct list_head stream_list;
1598 DEBUG("Overwriting `%s' in-place", w->filename);
1600 /* Make sure that the integrity table (if present) is after the XML
1601 * data, and that there are no stream resources, metadata resources, or
1602 * lookup tables after the XML data. Otherwise, these data would be
1604 if (w->hdr.integrity.offset != 0 &&
1605 w->hdr.integrity.offset < w->hdr.xml_res_entry.offset) {
1606 ERROR("Didn't expect the integrity table to be before the XML data");
1607 return WIMLIB_ERR_RESOURCE_ORDER;
1610 if (w->hdr.lookup_table_res_entry.offset > w->hdr.xml_res_entry.offset) {
1611 ERROR("Didn't expect the lookup table to be after the XML data");
1612 return WIMLIB_ERR_RESOURCE_ORDER;
1615 DEBUG("Identifying newly added streams");
1616 for_lookup_table_entry(w->lookup_table, lte_overwrite_prepare, NULL);
1617 INIT_LIST_HEAD(&stream_list);
1618 for (int i = modified_image_idx; i < w->hdr.image_count; i++) {
1619 DEBUG("Identifiying streams in image %d", i + 1);
1620 wimlib_assert(w->image_metadata[i].modified);
1621 wimlib_assert(!w->image_metadata[i].has_been_mounted_rw);
1622 wimlib_assert(w->image_metadata[i].root_dentry != NULL);
1623 wimlib_assert(w->image_metadata[i].metadata_lte != NULL);
1624 w->private = &stream_list;
1625 for_dentry_in_tree(w->image_metadata[i].root_dentry,
1626 dentry_find_streams_to_write, w);
1629 if (w->hdr.integrity.offset)
1630 old_wim_end = w->hdr.integrity.offset + w->hdr.integrity.size;
1632 old_wim_end = w->hdr.xml_res_entry.offset + w->hdr.xml_res_entry.size;
1634 ret = for_lookup_table_entry(w->lookup_table, check_resource_offset,
1639 DEBUG("old_wim_end = %"PRIu64, old_wim_end);
1641 INIT_LIST_HEAD(&stream_list);
1642 for_lookup_table_entry(w->lookup_table, find_new_streams,
1646 u64 num_new_streams = 0;
1647 struct list_head *cur;
1648 list_for_each(cur, &stream_list)
1650 DEBUG("%"PRIu64" new streams to write", num_new_streams);
1655 bool need_readable = false;
1656 if (write_flags & WIMLIB_WRITE_FLAG_CHECK_INTEGRITY)
1657 need_readable = true;
1658 ret = open_wim_writable(w, w->filename, trunc, need_readable);
1663 if (fseeko(w->out_fp, old_wim_end, SEEK_SET) != 0) {
1664 ERROR_WITH_ERRNO("Can't seek to end of WIM");
1665 return WIMLIB_ERR_WRITE;
1668 if (!list_empty(&stream_list)) {
1669 DEBUG("Writing newly added streams (offset = %"PRIu64")",
1671 ret = write_stream_list(&stream_list, w->out_fp,
1672 wimlib_get_compression_type(w),
1673 write_flags, num_threads);
1677 DEBUG("No new streams were added");
1680 for (int i = modified_image_idx; i < w->hdr.image_count; i++) {
1681 select_wim_image(w, i + 1);
1682 ret = write_metadata_resource(w);
1686 write_flags |= WIMLIB_WRITE_FLAG_REUSE_INTEGRITY_TABLE;
1687 ret = finish_write(w, WIM_ALL_IMAGES, write_flags);
1689 close_wim_writable(w);
1691 WARNING("Truncating `%s' to its original size (%"PRIu64" bytes)",
1692 w->filename, old_wim_end);
1693 truncate(w->filename, old_wim_end);
1698 static int overwrite_wim_via_tmpfile(WIMStruct *w, int write_flags,
1699 unsigned num_threads)
1701 size_t wim_name_len;
1704 DEBUG("Overwrining `%s' via a temporary file", w->filename);
1706 /* Write the WIM to a temporary file in the same directory as the
1708 wim_name_len = strlen(w->filename);
1709 char tmpfile[wim_name_len + 10];
1710 memcpy(tmpfile, w->filename, wim_name_len);
1711 randomize_char_array_with_alnum(tmpfile + wim_name_len, 9);
1712 tmpfile[wim_name_len + 9] = '\0';
1714 ret = wimlib_write(w, tmpfile, WIM_ALL_IMAGES,
1715 write_flags | WIMLIB_WRITE_FLAG_FSYNC,
1718 ERROR("Failed to write the WIM file `%s'", tmpfile);
1722 /* Close the original WIM file that was opened for reading. */
1723 if (w->fp != NULL) {
1728 DEBUG("Renaming `%s' to `%s'", tmpfile, w->filename);
1730 /* Rename the new file to the old file .*/
1731 if (rename(tmpfile, w->filename) != 0) {
1732 ERROR_WITH_ERRNO("Failed to rename `%s' to `%s'",
1733 tmpfile, w->filename);
1734 ret = WIMLIB_ERR_RENAME;
1738 if (write_flags & WIMLIB_WRITE_FLAG_SHOW_PROGRESS)
1739 printf("Successfully renamed `%s' to `%s'\n", tmpfile, w->filename);
1741 /* Re-open the WIM read-only. */
1742 w->fp = fopen(w->filename, "rb");
1743 if (w->fp == NULL) {
1744 ret = WIMLIB_ERR_REOPEN;
1745 WARNING("Failed to re-open `%s' read-only: %s",
1746 w->filename, strerror(errno));
1750 /* Remove temporary file. */
1751 if (unlink(tmpfile) != 0)
1752 WARNING("Failed to remove `%s': %s", tmpfile, strerror(errno));
1757 * Writes a WIM file to the original file that it was read from, overwriting it.
1759 WIMLIBAPI int wimlib_overwrite(WIMStruct *w, int write_flags,
1760 unsigned num_threads)
1763 return WIMLIB_ERR_INVALID_PARAM;
1765 write_flags &= WIMLIB_WRITE_MASK_PUBLIC;
1768 return WIMLIB_ERR_NO_FILENAME;
1770 if (w->hdr.total_parts != 1) {
1771 ERROR("Cannot modify a split WIM");
1772 return WIMLIB_ERR_SPLIT_UNSUPPORTED;
1775 if (!w->deletion_occurred && !(write_flags & WIMLIB_WRITE_FLAG_REBUILD)) {
1776 int i, modified_image_idx;
1777 for (i = 0; i < w->hdr.image_count && !w->image_metadata[i].modified; i++)
1779 modified_image_idx = i;
1780 for (; i < w->hdr.image_count && w->image_metadata[i].modified &&
1781 !w->image_metadata[i].has_been_mounted_rw; i++)
1783 if (i == w->hdr.image_count) {
1784 return overwrite_wim_inplace(w, write_flags, num_threads,
1785 modified_image_idx);
1788 return overwrite_wim_via_tmpfile(w, write_flags, num_threads);
1792 WIMLIBAPI int wimlib_overwrite_xml_and_header(WIMStruct *wim, int write_flags)
1794 return wimlib_overwrite(wim, write_flags, 1);