+ return 0;
+}
+
+/* Called when the main thread has read a new chunk of data. */
+static int
+main_writer_thread_cb(const void *chunk, size_t chunk_size, void *_ctx)
+{
+ struct main_writer_thread_ctx *ctx = _ctx;
+ int ret;
+ struct message *next_msg;
+ u64 next_chunk_in_msg;
+
+ /* Update SHA1 message digest for the stream currently being read by the
+ * main thread. */
+ sha1_update(&ctx->next_sha_ctx, chunk, chunk_size);
+
+ /* We send chunks of data to the compressor chunks in batches which we
+ * refer to as "messages". @next_msg is the message that is currently
+ * being prepared to send off. If it is NULL, that indicates that we
+ * need to start a new message. */
+ next_msg = ctx->next_msg;
+ if (!next_msg) {
+ /* We need to start a new message. First check to see if there
+ * is a message available in the list of available messages. If
+ * so, we can just take one. If not, all the messages (there is
+ * a fixed number of them, proportional to the number of
+ * threads) have been sent off to the compressor threads, so we
+ * receive messages from the compressor threads containing
+ * compressed chunks of data.
+ *
+ * We may need to receive multiple messages before one is
+ * actually available to use because messages received that are
+ * *not* for the very next set of chunks to compress must be
+ * buffered until it's time to write those chunks. */
+ while (list_empty(&ctx->available_msgs)) {
+ ret = receive_compressed_chunks(ctx);
+ if (ret)
+ return ret;
+ }
+
+ next_msg = container_of(ctx->available_msgs.next,
+ struct message, list);
+ list_del(&next_msg->list);
+ next_msg->complete = false;
+ next_msg->begin_chunk = ctx->next_chunk;
+ next_msg->num_chunks = min(MAX_CHUNKS_PER_MSG,
+ ctx->next_num_chunks - ctx->next_chunk);
+ ctx->next_msg = next_msg;
+ }
+
+ /* Fill in the next chunk to compress */
+ next_chunk_in_msg = ctx->next_chunk - next_msg->begin_chunk;
+
+ next_msg->uncompressed_chunk_sizes[next_chunk_in_msg] = chunk_size;
+ memcpy(next_msg->uncompressed_chunks[next_chunk_in_msg],
+ chunk, chunk_size);
+ ctx->next_chunk++;
+ if (++next_chunk_in_msg == next_msg->num_chunks) {
+ /* Send off an array of chunks to compress */
+ list_add_tail(&next_msg->list, &ctx->next_lte->msg_list);
+ shared_queue_put(ctx->res_to_compress_queue, next_msg);
+ ++ctx->num_outstanding_messages;
+ ctx->next_msg = NULL;
+ }
+ return 0;
+}
+
+static int
+main_writer_thread_finish(void *_ctx)
+{
+ struct main_writer_thread_ctx *ctx = _ctx;
+ int ret;
+ while (ctx->num_outstanding_messages != 0) {
+ ret = receive_compressed_chunks(ctx);
+ if (ret)
+ return ret;
+ }
+ wimlib_assert(list_empty(&ctx->outstanding_streams));
+ return do_write_stream_list_serial(&ctx->serial_streams,
+ ctx->lookup_table,
+ ctx->out_fd,
+ ctx->out_ctype,
+ ctx->write_resource_flags,
+ ctx->progress_data);
+}
+
+static int
+submit_stream_for_compression(struct wim_lookup_table_entry *lte,
+ struct main_writer_thread_ctx *ctx)
+{
+ int ret;
+
+ /* Read the entire stream @lte, feeding its data chunks to the
+ * compressor threads. Also SHA1-sum the stream; this is required in
+ * the case that @lte is unhashed, and a nice additional verification
+ * when @lte is already hashed. */
+ sha1_init(&ctx->next_sha_ctx);
+ ctx->next_chunk = 0;
+ ctx->next_num_chunks = wim_resource_chunks(lte);
+ ctx->next_lte = lte;
+ INIT_LIST_HEAD(<e->msg_list);
+ list_add_tail(<e->being_compressed_list, &ctx->outstanding_streams);
+ ret = read_resource_prefix(lte, wim_resource_size(lte),
+ main_writer_thread_cb, ctx, 0);
+ if (ret)
+ return ret;
+ wimlib_assert(ctx->next_chunk == ctx->next_num_chunks);
+ return finalize_and_check_sha1(&ctx->next_sha_ctx, lte);
+}
+
+static int
+main_thread_process_next_stream(struct wim_lookup_table_entry *lte, void *_ctx)
+{
+ struct main_writer_thread_ctx *ctx = _ctx;
+ int ret;
+
+ if (wim_resource_size(lte) < 1000 ||
+ ctx->out_ctype == WIMLIB_COMPRESSION_TYPE_NONE ||
+ (lte->resource_location == RESOURCE_IN_WIM &&
+ !(ctx->write_resource_flags & WIMLIB_WRITE_RESOURCE_FLAG_RECOMPRESS) &&
+ lte->wim->compression_type == ctx->out_ctype))
+ {
+ /* Stream is too small or isn't being compressed. Process it by
+ * the main thread when we have a chance. We can't necessarily
+ * process it right here, as the main thread could be in the
+ * middle of writing a different stream. */
+ list_add_tail(<e->write_streams_list, &ctx->serial_streams);
+ lte->deferred = 1;
+ ret = 0;
+ } else {
+ ret = submit_stream_for_compression(lte, ctx);
+ }
+ lte->no_progress = 1;
+ return ret;
+}
+
+static long
+get_default_num_threads(void)
+{
+#ifdef __WIN32__
+ return win32_get_number_of_processors();
+#else
+ return sysconf(_SC_NPROCESSORS_ONLN);
+#endif
+}
+
+/* Equivalent to write_stream_list_serial(), except this takes a @num_threads
+ * parameter and will perform compression using that many threads. Falls
+ * back to write_stream_list_serial() on certain errors, such as a failure to
+ * create the number of threads requested.
+ *
+ * High level description of the algorithm for writing compressed streams in
+ * parallel: We perform compression on chunks of size WIM_CHUNK_SIZE bytes
+ * rather than on full files. The currently executing thread becomes the main
+ * thread and is entirely in charge of reading the data to compress (which may
+ * be in any location understood by the resource code--- such as in an external
+ * file being captured, or in another WIM file from which an image is being
+ * exported) and actually writing the compressed data to the output file.
+ * Additional threads are "compressor threads" and all execute the
+ * compressor_thread_proc, where they repeatedly retrieve buffers of data from
+ * the main thread, compress them, and hand them back to the main thread.
+ *
+ * Certain streams, such as streams that do not need to be compressed (e.g.
+ * input compression type same as output compression type) or streams of very
+ * small size are placed in a list (main_writer_thread_ctx.serial_list) and
+ * handled entirely by the main thread at an appropriate time.
+ *
+ * At any given point in time, multiple streams may be having chunks compressed
+ * concurrently. The stream that the main thread is currently *reading* may be
+ * later in the list that the stream that the main thread is currently
+ * *writing*.
+ */
+static int
+write_stream_list_parallel(struct list_head *stream_list,
+ struct wim_lookup_table *lookup_table,
+ struct filedes *out_fd,
+ int out_ctype,
+ int write_resource_flags,
+ struct write_streams_progress_data *progress_data,
+ unsigned num_threads)
+{
+ int ret;
+ struct shared_queue res_to_compress_queue;
+ struct shared_queue compressed_res_queue;
+ pthread_t *compressor_threads = NULL;
+ union wimlib_progress_info *progress = &progress_data->progress;
+
+ if (num_threads == 0) {
+ long nthreads = get_default_num_threads();
+ if (nthreads < 1 || nthreads > UINT_MAX) {
+ WARNING("Could not determine number of processors! Assuming 1");
+ goto out_serial;
+ } else if (nthreads == 1) {
+ goto out_serial_quiet;
+ } else {
+ num_threads = nthreads;
+ }
+ }
+
+ DEBUG("Writing stream list of size %"PRIu64" "
+ "(parallel version, num_threads=%u)",
+ progress->write_streams.total_streams, num_threads);
+
+ progress->write_streams.num_threads = num_threads;
+
+ static const size_t MESSAGES_PER_THREAD = 2;
+ size_t queue_size = (size_t)(num_threads * MESSAGES_PER_THREAD);
+
+ DEBUG("Initializing shared queues (queue_size=%zu)", queue_size);
+
+ ret = shared_queue_init(&res_to_compress_queue, queue_size);
+ if (ret)
+ goto out_serial;
+
+ ret = shared_queue_init(&compressed_res_queue, queue_size);
+ if (ret)
+ goto out_destroy_res_to_compress_queue;
+
+ struct compressor_thread_params params;
+ params.res_to_compress_queue = &res_to_compress_queue;
+ params.compressed_res_queue = &compressed_res_queue;
+ params.compress = get_compress_func(out_ctype);
+
+ compressor_threads = MALLOC(num_threads * sizeof(pthread_t));
+ if (!compressor_threads) {
+ ret = WIMLIB_ERR_NOMEM;
+ goto out_destroy_compressed_res_queue;
+ }
+
+ for (unsigned i = 0; i < num_threads; i++) {
+ DEBUG("pthread_create thread %u of %u", i + 1, num_threads);
+ ret = pthread_create(&compressor_threads[i], NULL,
+ compressor_thread_proc, ¶ms);
+ if (ret != 0) {
+ ret = -1;
+ ERROR_WITH_ERRNO("Failed to create compressor "
+ "thread %u of %u",
+ i + 1, num_threads);
+ num_threads = i;
+ goto out_join;
+ }
+ }
+
+ if (progress_data->progress_func) {
+ progress_data->progress_func(WIMLIB_PROGRESS_MSG_WRITE_STREAMS,
+ progress);
+ }
+
+ struct main_writer_thread_ctx ctx;
+ ctx.stream_list = stream_list;
+ ctx.lookup_table = lookup_table;
+ ctx.out_fd = out_fd;
+ ctx.out_ctype = out_ctype;
+ ctx.res_to_compress_queue = &res_to_compress_queue;
+ ctx.compressed_res_queue = &compressed_res_queue;
+ ctx.num_messages = queue_size;
+ ctx.write_resource_flags = write_resource_flags;
+ ctx.progress_data = progress_data;
+ ret = main_writer_thread_init_ctx(&ctx);
+ if (ret)
+ goto out_join;
+ ret = do_write_stream_list(stream_list, lookup_table,
+ main_thread_process_next_stream,
+ &ctx, progress_data);
+ if (ret)
+ goto out_destroy_ctx;
+
+ /* The main thread has finished reading all streams that are going to be
+ * compressed in parallel, and it now needs to wait for all remaining
+ * chunks to be compressed so that the remaining streams can actually be
+ * written to the output file. Furthermore, any remaining streams that
+ * had processing deferred to the main thread need to be handled. These
+ * tasks are done by the main_writer_thread_finish() function. */
+ ret = main_writer_thread_finish(&ctx);
+out_destroy_ctx:
+ main_writer_thread_destroy_ctx(&ctx);
+out_join:
+ for (unsigned i = 0; i < num_threads; i++)
+ shared_queue_put(&res_to_compress_queue, NULL);
+
+ for (unsigned i = 0; i < num_threads; i++) {
+ if (pthread_join(compressor_threads[i], NULL)) {
+ WARNING_WITH_ERRNO("Failed to join compressor "
+ "thread %u of %u",
+ i + 1, num_threads);
+ }
+ }
+ FREE(compressor_threads);
+out_destroy_compressed_res_queue:
+ shared_queue_destroy(&compressed_res_queue);
+out_destroy_res_to_compress_queue:
+ shared_queue_destroy(&res_to_compress_queue);
+ if (ret >= 0 && ret != WIMLIB_ERR_NOMEM)
+ return ret;
+out_serial:
+ WARNING("Falling back to single-threaded compression");
+out_serial_quiet:
+ return write_stream_list_serial(stream_list,
+ lookup_table,
+ out_fd,
+ out_ctype,
+ write_resource_flags,
+ progress_data);
+
+}
+#endif
+
+/*
+ * Write a list of streams to a WIM (@out_fd) using the compression type
+ * @out_ctype and up to @num_threads compressor threads.
+ */
+static int
+write_stream_list(struct list_head *stream_list,
+ struct wim_lookup_table *lookup_table,
+ struct filedes *out_fd, int out_ctype, int write_flags,
+ unsigned num_threads, wimlib_progress_func_t progress_func)
+{
+ struct wim_lookup_table_entry *lte;
+ size_t num_streams = 0;
+ u64 total_bytes = 0;
+ u64 total_compression_bytes = 0;
+ struct write_streams_progress_data progress_data;
+ int ret;
+ int write_resource_flags;
+ unsigned total_parts = 0;
+ WIMStruct *prev_wim_part = NULL;
+
+ if (list_empty(stream_list)) {
+ DEBUG("No streams to write.");
+ return 0;
+ }
+
+ write_resource_flags = write_flags_to_resource_flags(write_flags);
+
+ DEBUG("Writing stream list (offset = %"PRIu64", write_resource_flags=0x%08x)",
+ out_fd->offset, write_resource_flags);
+
+ sort_stream_list_by_sequential_order(stream_list,
+ offsetof(struct wim_lookup_table_entry,
+ write_streams_list));
+
+ /* Calculate the total size of the streams to be written. Note: this
+ * will be the uncompressed size, as we may not know the compressed size
+ * yet, and also this will assume that every unhashed stream will be
+ * written (which will not necessarily be the case). */
+ list_for_each_entry(lte, stream_list, write_streams_list) {
+ num_streams++;
+ total_bytes += wim_resource_size(lte);
+ if (out_ctype != WIMLIB_COMPRESSION_TYPE_NONE
+ && (wim_resource_compression_type(lte) != out_ctype ||
+ (write_resource_flags & WIMLIB_WRITE_RESOURCE_FLAG_RECOMPRESS)))
+ {
+ total_compression_bytes += wim_resource_size(lte);
+ }
+ if (lte->resource_location == RESOURCE_IN_WIM) {
+ if (prev_wim_part != lte->wim) {
+ prev_wim_part = lte->wim;
+ total_parts++;
+ }
+ }
+ }
+
+ memset(&progress_data, 0, sizeof(progress_data));
+ progress_data.progress_func = progress_func;
+
+ progress_data.progress.write_streams.total_bytes = total_bytes;
+ progress_data.progress.write_streams.total_streams = num_streams;
+ progress_data.progress.write_streams.completed_bytes = 0;
+ progress_data.progress.write_streams.completed_streams = 0;
+ progress_data.progress.write_streams.num_threads = num_threads;
+ progress_data.progress.write_streams.compression_type = out_ctype;
+ progress_data.progress.write_streams.total_parts = total_parts;
+ progress_data.progress.write_streams.completed_parts = 0;
+
+ progress_data.next_progress = 0;
+ progress_data.prev_wim_part = NULL;
+
+#ifdef ENABLE_MULTITHREADED_COMPRESSION
+ if (total_compression_bytes >= 2000000 && num_threads != 1)
+ ret = write_stream_list_parallel(stream_list,
+ lookup_table,
+ out_fd,
+ out_ctype,
+ write_resource_flags,
+ &progress_data,
+ num_threads);
+ else
+#endif
+ ret = write_stream_list_serial(stream_list,
+ lookup_table,
+ out_fd,
+ out_ctype,
+ write_resource_flags,
+ &progress_data);
+ if (ret == 0)
+ DEBUG("Successfully wrote stream list.");
+ else
+ DEBUG("Failed to write stream list.");
+ return ret;
+}
+
+struct stream_size_table {
+ struct hlist_head *array;
+ size_t num_entries;
+ size_t capacity;
+};
+
+static int
+init_stream_size_table(struct stream_size_table *tab, size_t capacity)
+{
+ tab->array = CALLOC(capacity, sizeof(tab->array[0]));
+ if (!tab->array)
+ return WIMLIB_ERR_NOMEM;
+ tab->num_entries = 0;
+ tab->capacity = capacity;
+ return 0;
+}
+
+static void
+destroy_stream_size_table(struct stream_size_table *tab)
+{
+ FREE(tab->array);
+}
+
+static int
+stream_size_table_insert(struct wim_lookup_table_entry *lte, void *_tab)
+{
+ struct stream_size_table *tab = _tab;
+ size_t pos;
+ struct wim_lookup_table_entry *same_size_lte;
+ struct hlist_node *tmp;
+
+ pos = hash_u64(wim_resource_size(lte)) % tab->capacity;
+ lte->unique_size = 1;
+ hlist_for_each_entry(same_size_lte, tmp, &tab->array[pos], hash_list_2) {
+ if (wim_resource_size(same_size_lte) == wim_resource_size(lte)) {
+ lte->unique_size = 0;
+ same_size_lte->unique_size = 0;
+ break;
+ }
+ }
+
+ hlist_add_head(<e->hash_list_2, &tab->array[pos]);
+ tab->num_entries++;
+ return 0;
+}
+
+struct find_streams_ctx {
+ WIMStruct *wim;
+ int write_flags;
+ struct list_head stream_list;
+ struct stream_size_table stream_size_tab;
+};
+
+static void
+lte_reference_for_logical_write(struct wim_lookup_table_entry *lte,
+ struct find_streams_ctx *ctx,
+ unsigned nref)
+{
+ if (lte->out_refcnt == 0) {
+ stream_size_table_insert(lte, &ctx->stream_size_tab);
+ list_add_tail(<e->write_streams_list, &ctx->stream_list);
+ }
+ lte->out_refcnt += nref;
+}
+
+static int
+do_lte_full_reference_for_logical_write(struct wim_lookup_table_entry *lte,
+ void *_ctx)
+{
+ struct find_streams_ctx *ctx = _ctx;
+ lte->out_refcnt = 0;
+ lte_reference_for_logical_write(lte, ctx,
+ (lte->refcnt ? lte->refcnt : 1));
+ return 0;
+}
+
+static int
+inode_find_streams_to_write(struct wim_inode *inode,
+ struct wim_lookup_table *table,
+ struct find_streams_ctx *ctx)
+{
+ struct wim_lookup_table_entry *lte;
+ unsigned i;
+
+ for (i = 0; i <= inode->i_num_ads; i++) {
+ lte = inode_stream_lte(inode, i, table);
+ if (lte)
+ lte_reference_for_logical_write(lte, ctx, inode->i_nlink);
+ else if (!is_zero_hash(inode_stream_hash(inode, i)))
+ return WIMLIB_ERR_RESOURCE_NOT_FOUND;
+ }
+ return 0;
+}
+
+static int
+image_find_streams_to_write(WIMStruct *wim)
+{
+ struct find_streams_ctx *ctx;
+ struct wim_image_metadata *imd;
+ struct wim_inode *inode;
+ struct wim_lookup_table_entry *lte;
+ int ret;
+
+ ctx = wim->private;
+ imd = wim_get_current_image_metadata(wim);
+
+ image_for_each_unhashed_stream(lte, imd)
+ lte->out_refcnt = 0;
+
+ /* Go through this image's inodes to find any streams that have not been
+ * found yet. */
+ image_for_each_inode(inode, imd) {
+ ret = inode_find_streams_to_write(inode, wim->lookup_table, ctx);
+ if (ret)
+ return ret;
+ }
+ return 0;
+}
+
+/*
+ * Build a list of streams (via `struct wim_lookup_table_entry's) included in
+ * the "logical write" of the WIM, meaning all streams that are referenced at
+ * least once by dentries in the the image(s) being written. 'out_refcnt' on
+ * each stream being included in the logical write is set to the number of
+ * references from dentries in the image(s). Furthermore, 'unique_size' on each
+ * stream being included in the logical write is set to indicate whether that
+ * stream has a unique size relative to the streams being included in the
+ * logical write. Still furthermore, 'part_number' on each stream being
+ * included in the logical write is set to the part number given in the
+ * in-memory header of @p wim.
+ *
+ * This is considered a "logical write" because it does not take into account
+ * filtering out streams already present in the WIM (in the case of an in place
+ * overwrite) or present in other WIMs (in case of creating delta WIM).
+ */
+static int
+prepare_logical_stream_list(WIMStruct *wim, int image, bool streams_ok,
+ struct find_streams_ctx *ctx)
+{
+ int ret;
+ struct wim_lookup_table_entry *lte;
+
+ if (streams_ok && (image == WIMLIB_ALL_IMAGES ||
+ (image == 1 && wim->hdr.image_count == 1)))
+ {
+ /* Fast case: Assume that all streams are being written and
+ * that the reference counts are correct. */
+ struct wim_lookup_table_entry *lte;
+ struct wim_image_metadata *imd;
+ unsigned i;
+
+ for_lookup_table_entry(wim->lookup_table,
+ do_lte_full_reference_for_logical_write, ctx);
+ for (i = 0; i < wim->hdr.image_count; i++) {
+ imd = wim->image_metadata[i];
+ image_for_each_unhashed_stream(lte, imd)
+ do_lte_full_reference_for_logical_write(lte, ctx);
+ }
+ } else {
+ /* Slow case: Walk through the images being written and
+ * determine the streams referenced. */
+ for_lookup_table_entry(wim->lookup_table, lte_zero_out_refcnt, NULL);
+ wim->private = ctx;
+ ret = for_image(wim, image, image_find_streams_to_write);
+ if (ret)
+ return ret;
+ }
+
+ list_for_each_entry(lte, &ctx->stream_list, write_streams_list)
+ lte->part_number = wim->hdr.part_number;
+ return 0;
+}
+
+static int
+process_filtered_stream(struct wim_lookup_table_entry *lte, void *_ctx)
+{
+ struct find_streams_ctx *ctx = _ctx;
+ u16 filtered = 0;
+
+ /* Calculate and set lte->filtered. */
+ if (lte->resource_location == RESOURCE_IN_WIM) {
+ if (lte->wim == ctx->wim &&
+ (ctx->write_flags & WIMLIB_WRITE_FLAG_OVERWRITE))
+ filtered |= FILTERED_SAME_WIM;
+ if (lte->wim != ctx->wim &&
+ (ctx->write_flags & WIMLIB_WRITE_FLAG_SKIP_EXTERNAL_WIMS))
+ filtered |= FILTERED_EXTERNAL_WIM;
+ }
+ lte->filtered = filtered;
+
+ /* Filtered streams get inserted into the stream size table too, unless
+ * they already were. This is because streams that are checksummed
+ * on-the-fly during the write should not be written if they are
+ * duplicates of filtered stream. */
+ if (lte->filtered && lte->out_refcnt == 0)
+ stream_size_table_insert(lte, &ctx->stream_size_tab);
+ return 0;
+}
+
+static int
+mark_stream_not_filtered(struct wim_lookup_table_entry *lte, void *_ignore)
+{
+ lte->filtered = 0;
+ return 0;
+}
+
+/* Given the list of streams to include in a logical write of a WIM, handle
+ * filtering out streams already present in the WIM or already present in
+ * external WIMs, depending on the write flags provided. */
+static void
+handle_stream_filtering(struct find_streams_ctx *ctx)
+{
+ struct wim_lookup_table_entry *lte, *tmp;
+
+ if (!(ctx->write_flags & (WIMLIB_WRITE_FLAG_OVERWRITE |
+ WIMLIB_WRITE_FLAG_SKIP_EXTERNAL_WIMS)))
+ {
+ for_lookup_table_entry(ctx->wim->lookup_table,
+ mark_stream_not_filtered, ctx);
+ return;
+ }
+
+ for_lookup_table_entry(ctx->wim->lookup_table,
+ process_filtered_stream, ctx);
+
+ /* Streams in logical write list that were filtered can be removed. */
+ list_for_each_entry_safe(lte, tmp, &ctx->stream_list,
+ write_streams_list)
+ if (lte->filtered)
+ list_del(<e->write_streams_list);
+}
+
+/* Prepares list of streams to write for the specified WIM image(s). This wraps
+ * around prepare_logical_stream_list() to handle filtering out streams already
+ * present in the WIM or already present in external WIMs, depending on the
+ * write flags provided.
+ *
+ * Note: some additional data is stored in each `struct wim_lookup_table_entry':
+ *
+ * - 'out_refcnt' is set to the number of references found for the logical write.
+ * This will be nonzero on all streams in the list returned by this function,
+ * but will also be nonzero on streams not in the list that were included in
+ * the logical write list, but filtered out from the returned list.
+ * - 'filtered' is set to nonzero if the stream was filtered. Filtered streams
+ * are not included in the list of streams returned by this function.
+ * - 'unique_size' is set if the stream has a unique size among all streams in
+ * the logical write plus any filtered streams in the entire WIM that could
+ * potentially turn out to have the same checksum as a yet-to-be-checksummed
+ * stream being written.
+ */
+static int
+prepare_stream_list(WIMStruct *wim, int image, int write_flags,
+ struct list_head *stream_list)
+{
+ int ret;
+ bool streams_ok;
+ struct find_streams_ctx ctx;
+
+ INIT_LIST_HEAD(&ctx.stream_list);
+ ret = init_stream_size_table(&ctx.stream_size_tab,
+ wim->lookup_table->capacity);
+ if (ret)
+ return ret;
+ ctx.write_flags = write_flags;
+ ctx.wim = wim;
+
+ streams_ok = ((write_flags & WIMLIB_WRITE_FLAG_STREAMS_OK) != 0);
+
+ ret = prepare_logical_stream_list(wim, image, streams_ok, &ctx);
+ if (ret)
+ goto out_destroy_table;
+
+ handle_stream_filtering(&ctx);
+ list_transfer(&ctx.stream_list, stream_list);
+ ret = 0;
+out_destroy_table:
+ destroy_stream_size_table(&ctx.stream_size_tab);
+ return ret;
+}
+
+static int
+write_wim_streams(WIMStruct *wim, int image, int write_flags,
+ unsigned num_threads,
+ wimlib_progress_func_t progress_func,
+ struct list_head *stream_list_override)
+{
+ int ret;
+ struct list_head _stream_list;
+ struct list_head *stream_list;
+ struct wim_lookup_table_entry *lte;
+
+ if (stream_list_override == NULL) {
+ /* Normal case: prepare stream list from image(s) being written.
+ */
+ stream_list = &_stream_list;
+ ret = prepare_stream_list(wim, image, write_flags, stream_list);
+ if (ret)
+ return ret;
+ } else {
+ /* Currently only as a result of wimlib_split() being called:
+ * use stream list already explicitly provided. Use existing
+ * reference counts. */
+ stream_list = stream_list_override;
+ list_for_each_entry(lte, stream_list, write_streams_list) {
+ lte->out_refcnt = (lte->refcnt ? lte->refcnt : 1);
+ lte->part_number = wim->hdr.part_number;
+ }
+ }
+
+ return write_stream_list(stream_list,
+ wim->lookup_table,
+ &wim->out_fd,
+ wim->compression_type,
+ write_flags,
+ num_threads,
+ progress_func);
+}
+
+static int
+write_wim_metadata_resources(WIMStruct *wim, int image, int write_flags,
+ wimlib_progress_func_t progress_func)
+{
+ int ret;
+ int start_image;
+ int end_image;
+ int write_resource_flags;
+
+ if (write_flags & WIMLIB_WRITE_FLAG_NO_METADATA) {
+ DEBUG("Not writing any metadata resources.");
+ return 0;
+ }
+
+ write_resource_flags = write_flags_to_resource_flags(write_flags);
+
+ DEBUG("Writing metadata resources (offset=%"PRIu64")",
+ wim->out_fd.offset);
+
+ if (progress_func)
+ progress_func(WIMLIB_PROGRESS_MSG_WRITE_METADATA_BEGIN, NULL);
+
+ if (image == WIMLIB_ALL_IMAGES) {
+ start_image = 1;
+ end_image = wim->hdr.image_count;
+ } else {
+ start_image = image;
+ end_image = image;
+ }
+
+ for (int i = start_image; i <= end_image; i++) {
+ struct wim_image_metadata *imd;
+
+ imd = wim->image_metadata[i - 1];
+ /* Build a new metadata resource only if image was modified from
+ * the original (or was newly added). Otherwise just copy the
+ * existing one. */
+ if (imd->modified) {
+ DEBUG("Image %u was modified; building and writing new "
+ "metadata resource", i);
+ ret = write_metadata_resource(wim, i,
+ write_resource_flags);
+ } else if (write_flags & WIMLIB_WRITE_FLAG_OVERWRITE) {
+ DEBUG("Image %u was not modified; re-using existing "
+ "metadata resource.", i);
+ copy_resource_entry(&imd->metadata_lte->output_resource_entry,
+ &imd->metadata_lte->resource_entry);
+ ret = 0;
+ } else {
+ DEBUG("Image %u was not modified; copying existing "
+ "metadata resource.", i);
+ ret = write_wim_resource(imd->metadata_lte,
+ &wim->out_fd,
+ wim->compression_type,
+ &imd->metadata_lte->output_resource_entry,
+ write_resource_flags);
+ }
+ if (ret)
+ return ret;
+ }
+ if (progress_func)
+ progress_func(WIMLIB_PROGRESS_MSG_WRITE_METADATA_END, NULL);
+ return 0;
+}
+
+static int
+open_wim_writable(WIMStruct *wim, const tchar *path, int open_flags)
+{
+ int raw_fd;
+ DEBUG("Opening \"%"TS"\" for writing.", path);
+
+ raw_fd = topen(path, open_flags | O_BINARY, 0644);
+ if (raw_fd < 0) {
+ ERROR_WITH_ERRNO("Failed to open \"%"TS"\" for writing", path);
+ return WIMLIB_ERR_OPEN;
+ }
+ filedes_init(&wim->out_fd, raw_fd);
+ return 0;
+}
+
+static int
+close_wim_writable(WIMStruct *wim, int write_flags)
+{
+ int ret = 0;
+
+ if (!(write_flags & WIMLIB_WRITE_FLAG_FILE_DESCRIPTOR))
+ if (filedes_valid(&wim->out_fd))
+ if (filedes_close(&wim->out_fd))
+ ret = WIMLIB_ERR_WRITE;
+ filedes_invalidate(&wim->out_fd);
+ return ret;
+}
+
+/*
+ * Finish writing a WIM file: write the lookup table, xml data, and integrity
+ * table, then overwrite the WIM header. Always closes the WIM file descriptor
+ * (wim->out_fd).
+ *
+ * write_flags is a bitwise OR of the following:
+ *
+ * (public) WIMLIB_WRITE_FLAG_CHECK_INTEGRITY:
+ * Include an integrity table.
+ *
+ * (public) WIMLIB_WRITE_FLAG_FSYNC:
+ * fsync() the output file before closing it.
+ *
+ * (public) WIMLIB_WRITE_FLAG_PIPABLE:
+ * Writing a pipable WIM, possibly to a pipe; include pipable WIM
+ * stream headers before the lookup table and XML data, and also
+ * write the WIM header at the end instead of seeking to the
+ * beginning. Can't be combined with
+ * WIMLIB_WRITE_FLAG_CHECK_INTEGRITY.
+ *
+ * (private) WIMLIB_WRITE_FLAG_NO_LOOKUP_TABLE:
+ * Don't write the lookup table.
+ *
+ * (private) WIMLIB_WRITE_FLAG_REUSE_INTEGRITY_TABLE:
+ * When (if) writing the integrity table, re-use entries from the
+ * existing integrity table, if possible.
+ *
+ * (private) WIMLIB_WRITE_FLAG_CHECKPOINT_AFTER_XML:
+ * After writing the XML data but before writing the integrity
+ * table, write a temporary WIM header and flush the stream so that
+ * the WIM is less likely to become corrupted upon abrupt program
+ * termination.
+ * (private) WIMLIB_WRITE_FLAG_HEADER_AT_END:
+ * Instead of overwriting the WIM header at the beginning of the
+ * file, simply append it to the end of the file. (Used when
+ * writing to pipe.)
+ * (private) WIMLIB_WRITE_FLAG_USE_EXISTING_TOTALBYTES:
+ * Use the existing <TOTALBYTES> stored in the in-memory XML
+ * information, rather than setting it to the offset of the XML
+ * data being written.
+ */
+static int
+finish_write(WIMStruct *wim, int image, int write_flags,
+ wimlib_progress_func_t progress_func,
+ struct list_head *stream_list_override)
+{
+ int ret;
+ off_t hdr_offset;
+ int write_resource_flags;
+ off_t old_lookup_table_end;
+ off_t new_lookup_table_end;
+ u64 xml_totalbytes;
+
+ write_resource_flags = write_flags_to_resource_flags(write_flags);
+
+ /* In the WIM header, there is room for the resource entry for a
+ * metadata resource labeled as the "boot metadata". This entry should
+ * be zeroed out if there is no bootable image (boot_idx 0). Otherwise,
+ * it should be a copy of the resource entry for the image that is
+ * marked as bootable. This is not well documented... */
+ if (wim->hdr.boot_idx == 0) {
+ zero_resource_entry(&wim->hdr.boot_metadata_res_entry);
+ } else {
+ copy_resource_entry(&wim->hdr.boot_metadata_res_entry,
+ &wim->image_metadata[wim->hdr.boot_idx- 1
+ ]->metadata_lte->output_resource_entry);
+ }
+
+ /* Write lookup table. (Save old position first.) */
+ old_lookup_table_end = wim->hdr.lookup_table_res_entry.offset +
+ wim->hdr.lookup_table_res_entry.size;
+ if (!(write_flags & WIMLIB_WRITE_FLAG_NO_LOOKUP_TABLE)) {
+ ret = write_wim_lookup_table(wim, image, write_flags,
+ &wim->hdr.lookup_table_res_entry,
+ stream_list_override);
+ if (ret)
+ goto out_close_wim;
+ }
+
+ /* Write XML data. */
+ xml_totalbytes = wim->out_fd.offset;
+ if (write_flags & WIMLIB_WRITE_FLAG_USE_EXISTING_TOTALBYTES)
+ xml_totalbytes = WIM_TOTALBYTES_USE_EXISTING;
+ ret = write_wim_xml_data(wim, image, xml_totalbytes,
+ &wim->hdr.xml_res_entry,
+ write_resource_flags);
+ if (ret)
+ goto out_close_wim;
+
+ if (write_flags & WIMLIB_WRITE_FLAG_CHECK_INTEGRITY) {
+ if (write_flags & WIMLIB_WRITE_FLAG_CHECKPOINT_AFTER_XML) {
+ struct wim_header checkpoint_hdr;
+ memcpy(&checkpoint_hdr, &wim->hdr, sizeof(struct wim_header));
+ zero_resource_entry(&checkpoint_hdr.integrity);
+ checkpoint_hdr.flags |= WIM_HDR_FLAG_WRITE_IN_PROGRESS;
+ ret = write_wim_header_at_offset(&checkpoint_hdr,
+ &wim->out_fd, 0);
+ if (ret)
+ goto out_close_wim;
+ }
+
+ if (!(write_flags & WIMLIB_WRITE_FLAG_REUSE_INTEGRITY_TABLE))
+ old_lookup_table_end = 0;
+
+ new_lookup_table_end = wim->hdr.lookup_table_res_entry.offset +
+ wim->hdr.lookup_table_res_entry.size;
+
+ ret = write_integrity_table(wim,
+ new_lookup_table_end,
+ old_lookup_table_end,
+ progress_func);
+ if (ret)
+ goto out_close_wim;
+ } else {
+ zero_resource_entry(&wim->hdr.integrity);
+ }
+
+ wim->hdr.flags &= ~WIM_HDR_FLAG_WRITE_IN_PROGRESS;
+ hdr_offset = 0;
+ if (write_flags & WIMLIB_WRITE_FLAG_HEADER_AT_END)
+ hdr_offset = wim->out_fd.offset;
+ ret = write_wim_header_at_offset(&wim->hdr, &wim->out_fd, hdr_offset);
+ if (ret)
+ goto out_close_wim;
+
+ if (write_flags & WIMLIB_WRITE_FLAG_FSYNC) {
+ if (fsync(wim->out_fd.fd)) {
+ ERROR_WITH_ERRNO("Error syncing data to WIM file");
+ ret = WIMLIB_ERR_WRITE;
+ goto out_close_wim;
+ }
+ }
+
+ ret = 0;
+out_close_wim:
+ if (close_wim_writable(wim, write_flags)) {
+ if (ret == 0) {
+ ERROR_WITH_ERRNO("Failed to close the output WIM file");
+ ret = WIMLIB_ERR_WRITE;
+ }
+ }
+ return ret;
+}
+
+#if defined(HAVE_SYS_FILE_H) && defined(HAVE_FLOCK)
+int
+lock_wim(WIMStruct *wim, int fd)
+{
+ int ret = 0;
+ if (fd != -1 && !wim->wim_locked) {
+ ret = flock(fd, LOCK_EX | LOCK_NB);
+ if (ret != 0) {
+ if (errno == EWOULDBLOCK) {
+ ERROR("`%"TS"' is already being modified or has been "
+ "mounted read-write\n"
+ " by another process!", wim->filename);
+ ret = WIMLIB_ERR_ALREADY_LOCKED;
+ } else {
+ WARNING_WITH_ERRNO("Failed to lock `%"TS"'",
+ wim->filename);
+ ret = 0;
+ }
+ } else {
+ wim->wim_locked = 1;
+ }
+ }
+ return ret;
+}
+#endif
+
+/*
+ * Perform the intermediate stages of creating a "pipable" WIM (i.e. a WIM
+ * capable of being applied from a pipe). Such a WIM looks like:
+ *
+ * Pipable WIMs are a wimlib-specific modification of the WIM format such that
+ * images can be applied from them sequentially when the file data is sent over
+ * a pipe. In addition, a pipable WIM can be written sequentially to a pipe.
+ * The modifications made to the WIM format for pipable WIMs are:
+ *
+ * - Magic characters in header are "WLPWM\0\0\0" (wimlib pipable WIM) instead
+ * of "MSWIM\0\0\0". This lets wimlib know that the WIM is pipable and also
+ * should stop other software from trying to read the file as a normal WIM.
+ *
+ * - The header at the beginning of the file does not contain all the normal
+ * information; in particular it will have all 0's for the lookup table and
+ * XML data resource entries. This is because this information cannot be
+ * determined until the lookup table and XML data have been written.
+ * Consequently, wimlib will write the full header at the very end of the
+ * file. The header at the end, however, is only used when reading the WIM
+ * from a seekable file (not a pipe).
+ *
+ * - An extra copy of the XML data is placed directly after the header. This
+ * allows image names and sizes to be determined at an appropriate time when
+ * reading the WIM from a pipe. This copy of the XML data is ignored if the
+ * WIM is read from a seekable file (not a pipe).
+ *
+ * - The format of resources, or streams, has been modified to allow them to be
+ * used before the "lookup table" has been read. Each stream is prefixed with
+ * a `struct pwm_stream_hdr' that is basically an abbreviated form of `struct
+ * wim_lookup_table_entry_disk' that only contains the SHA1 message digest,
+ * uncompressed stream size, and flags that indicate whether the stream is
+ * compressed. The data of uncompressed streams then follows literally, while
+ * the data of compressed streams follows in a modified format. Compressed
+ * streams have no chunk table, since the chunk table cannot be written until
+ * all chunks have been compressed; instead, each compressed chunk is prefixed
+ * by a `struct pwm_chunk_hdr' that gives its size. However, the offsets are
+ * given in the chunk table as if these chunk headers were not present.
+ *
+ * - Metadata resources always come before other file resources (streams).
+ * (This does not by itself constitute an incompatibility with normal WIMs,
+ * since this is valid in normal WIMs.)
+ *
+ * - At least up to the end of the file resources, all components must be packed
+ * as tightly as possible; there cannot be any "holes" in the WIM. (This does
+ * not by itself consititute an incompatibility with normal WIMs, since this
+ * is valid in normal WIMs.)
+ *
+ * Note: the lookup table, XML data, and header at the end are not used when
+ * applying from a pipe. They exist to support functionality such as image
+ * application and export when the WIM is *not* read from a pipe.
+ *
+ * Layout of pipable WIM:
+ *
+ * ----------+----------+--------------------+----------------+--------------+------------+--------+
+ * | Header | XML data | Metadata resources | File resources | Lookup table | XML data | Header |
+ * ----------+----------+--------------------+----------------+--------------+------------+--------+
+ *
+ * Layout of normal WIM:
+ *
+ * +---------+--------------------+----------------+--------------+----------+
+ * | Header | Metadata resources | File resources | Lookup table | XML data |
+ * +---------+--------------------+----------------+--------------+----------+
+ *
+ * Do note that since pipable WIMs are not supported by Microsoft's software,
+ * wimlib does not create them unless explicitly requested (with
+ * WIMLIB_WRITE_FLAG_PIPABLE) and as stated above they use different magic
+ * characters to identify the file.
+ */
+static int
+write_pipable_wim(WIMStruct *wim, int image, int write_flags,
+ unsigned num_threads, wimlib_progress_func_t progress_func,
+ struct list_head *stream_list_override)
+{
+ int ret;
+ struct resource_entry xml_res_entry;
+
+ WARNING("Creating a pipable WIM, which will "
+ "be incompatible\n"
+ " with Microsoft's software (wimgapi/imagex/Dism).");
+
+ /* At this point, the header at the beginning of the file has already
+ * been written. */
+
+ /* For efficiency, when wimlib adds an image to the WIM with
+ * wimlib_add_image(), the SHA1 message digests of files is not
+ * calculated; instead, they are calculated while the files are being
+ * written. However, this does not work when writing a pipable WIM,
+ * since when writing a stream to a pipable WIM, its SHA1 message digest
+ * needs to be known before the stream data is written. Therefore,
+ * before getting much farther, we need to pre-calculate the SHA1
+ * message digests of all streams that will be written. */
+ ret = wim_checksum_unhashed_streams(wim);
+ if (ret)
+ return ret;
+
+ /* Write extra copy of the XML data. */
+ ret = write_wim_xml_data(wim, image, WIM_TOTALBYTES_OMIT,
+ &xml_res_entry,
+ WIMLIB_WRITE_RESOURCE_FLAG_PIPABLE);
+ if (ret)
+ return ret;
+
+ /* Write metadata resources for the image(s) being included in the
+ * output WIM. */
+ ret = write_wim_metadata_resources(wim, image, write_flags,
+ progress_func);
+ if (ret)
+ return ret;
+
+ /* Write streams needed for the image(s) being included in the output
+ * WIM, or streams needed for the split WIM part. */
+ return write_wim_streams(wim, image, write_flags, num_threads,
+ progress_func, stream_list_override);
+
+ /* The lookup table, XML data, and header at end are handled by
+ * finish_write(). */
+}
+
+/* Write a standalone WIM or split WIM (SWM) part to a new file or to a file
+ * descriptor. */
+int
+write_wim_part(WIMStruct *wim,
+ const void *path_or_fd,
+ int image,
+ int write_flags,
+ unsigned num_threads,
+ wimlib_progress_func_t progress_func,
+ unsigned part_number,
+ unsigned total_parts,
+ struct list_head *stream_list_override,
+ const u8 *guid)
+{
+ int ret;
+ struct wim_header hdr_save;
+ struct list_head lt_stream_list_override;
+
+ if (total_parts == 1)
+ DEBUG("Writing standalone WIM.");
+ else
+ DEBUG("Writing split WIM part %u/%u", part_number, total_parts);
+ if (image == WIMLIB_ALL_IMAGES)
+ DEBUG("Including all images.");
+ else
+ DEBUG("Including image %d only.", image);
+ if (write_flags & WIMLIB_WRITE_FLAG_FILE_DESCRIPTOR)
+ DEBUG("File descriptor: %d", *(const int*)path_or_fd);
+ else
+ DEBUG("Path: \"%"TS"\"", (const tchar*)path_or_fd);
+ DEBUG("Write flags: 0x%08x", write_flags);
+ if (write_flags & WIMLIB_WRITE_FLAG_CHECK_INTEGRITY)
+ DEBUG("\tCHECK_INTEGRITY");
+ if (write_flags & WIMLIB_WRITE_FLAG_REBUILD)
+ DEBUG("\tREBUILD");
+ if (write_flags & WIMLIB_WRITE_FLAG_RECOMPRESS)
+ DEBUG("\tRECOMPRESS");
+ if (write_flags & WIMLIB_WRITE_FLAG_FSYNC)
+ DEBUG("\tFSYNC");
+ if (write_flags & WIMLIB_WRITE_FLAG_SOFT_DELETE)
+ DEBUG("\tFSYNC");
+ if (write_flags & WIMLIB_WRITE_FLAG_IGNORE_READONLY_FLAG)
+ DEBUG("\tIGNORE_READONLY_FLAG");
+ if (write_flags & WIMLIB_WRITE_FLAG_PIPABLE)
+ DEBUG("\tPIPABLE");
+ if (write_flags & WIMLIB_WRITE_FLAG_FILE_DESCRIPTOR)
+ DEBUG("\tFILE_DESCRIPTOR");
+ if (write_flags & WIMLIB_WRITE_FLAG_NO_METADATA)
+ DEBUG("\tNO_METADATA");
+ if (write_flags & WIMLIB_WRITE_FLAG_USE_EXISTING_TOTALBYTES)
+ DEBUG("\tUSE_EXISTING_TOTALBYTES");
+ if (num_threads == 0)
+ DEBUG("Number of threads: autodetect");
+ else
+ DEBUG("Number of threads: %u", num_threads);
+ DEBUG("Progress function: %s", (progress_func ? "yes" : "no"));
+ DEBUG("Stream list: %s", (stream_list_override ? "specified" : "autodetect"));
+ DEBUG("GUID: %s", ((guid || wim->guid_set_explicitly) ?
+ "specified" : "generate new"));
+
+ /* Internally, this is always called with a valid part number and total
+ * parts. */
+ wimlib_assert(total_parts >= 1);
+ wimlib_assert(part_number >= 1 && part_number <= total_parts);
+
+ /* A valid image (or all images) must be specified. */
+ if (image != WIMLIB_ALL_IMAGES &&
+ (image < 1 || image > wim->hdr.image_count))
+ return WIMLIB_ERR_INVALID_IMAGE;
+
+ /* If we need to write metadata resources, make sure the ::WIMStruct has
+ * the needed information attached (e.g. is not a resource-only WIM,
+ * such as a non-first part of a split WIM). */
+ if (!wim_has_metadata(wim) &&
+ !(write_flags & WIMLIB_WRITE_FLAG_NO_METADATA))
+ return WIMLIB_ERR_METADATA_NOT_FOUND;
+
+ /* Check for contradictory flags. */
+ if ((write_flags & (WIMLIB_WRITE_FLAG_CHECK_INTEGRITY |
+ WIMLIB_WRITE_FLAG_NO_CHECK_INTEGRITY))
+ == (WIMLIB_WRITE_FLAG_CHECK_INTEGRITY |
+ WIMLIB_WRITE_FLAG_NO_CHECK_INTEGRITY))
+ return WIMLIB_ERR_INVALID_PARAM;
+
+ if ((write_flags & (WIMLIB_WRITE_FLAG_PIPABLE |
+ WIMLIB_WRITE_FLAG_NOT_PIPABLE))
+ == (WIMLIB_WRITE_FLAG_PIPABLE |
+ WIMLIB_WRITE_FLAG_NOT_PIPABLE))
+ return WIMLIB_ERR_INVALID_PARAM;
+
+ /* Save previous header, then start initializing the new one. */
+ memcpy(&hdr_save, &wim->hdr, sizeof(struct wim_header));
+
+ /* Set default integrity and pipable flags. */
+ if (!(write_flags & (WIMLIB_WRITE_FLAG_PIPABLE |
+ WIMLIB_WRITE_FLAG_NOT_PIPABLE)))
+ if (wim_is_pipable(wim))
+ write_flags |= WIMLIB_WRITE_FLAG_PIPABLE;
+
+ if (!(write_flags & (WIMLIB_WRITE_FLAG_CHECK_INTEGRITY |
+ WIMLIB_WRITE_FLAG_NO_CHECK_INTEGRITY)))
+ if (wim_has_integrity_table(wim))
+ write_flags |= WIMLIB_WRITE_FLAG_CHECK_INTEGRITY;
+
+ /* Set appropriate magic number. */
+ if (write_flags & WIMLIB_WRITE_FLAG_PIPABLE)
+ wim->hdr.magic = PWM_MAGIC;
+ else
+ wim->hdr.magic = WIM_MAGIC;
+
+ /* Clear header flags that will be set automatically. */
+ wim->hdr.flags &= ~(WIM_HDR_FLAG_METADATA_ONLY |
+ WIM_HDR_FLAG_RESOURCE_ONLY |
+ WIM_HDR_FLAG_SPANNED |
+ WIM_HDR_FLAG_WRITE_IN_PROGRESS);
+
+ /* Set SPANNED header flag if writing part of a split WIM. */
+ if (total_parts != 1)
+ wim->hdr.flags |= WIM_HDR_FLAG_SPANNED;
+
+ /* Set part number and total parts of split WIM. This will be 1 and 1
+ * if the WIM is standalone. */
+ wim->hdr.part_number = part_number;
+ wim->hdr.total_parts = total_parts;
+
+ /* Use GUID if specified; otherwise generate a new one. */
+ if (guid)
+ memcpy(wim->hdr.guid, guid, WIMLIB_GUID_LEN);
+ else if (!wim->guid_set_explicitly)
+ randomize_byte_array(wim->hdr.guid, WIMLIB_GUID_LEN);
+
+ /* Clear references to resources that have not been written yet. */
+ zero_resource_entry(&wim->hdr.lookup_table_res_entry);
+ zero_resource_entry(&wim->hdr.xml_res_entry);
+ zero_resource_entry(&wim->hdr.boot_metadata_res_entry);
+ zero_resource_entry(&wim->hdr.integrity);
+
+ /* Set image count and boot index correctly for single image writes. */
+ if (image != WIMLIB_ALL_IMAGES) {
+ wim->hdr.image_count = 1;
+ if (wim->hdr.boot_idx == image)
+ wim->hdr.boot_idx = 1;
+ else
+ wim->hdr.boot_idx = 0;
+ }
+
+ /* Split WIMs can't be bootable. */
+ if (total_parts != 1)
+ wim->hdr.boot_idx = 0;
+
+ /* Initialize output file descriptor. */
+ if (write_flags & WIMLIB_WRITE_FLAG_FILE_DESCRIPTOR) {
+ /* File descriptor was explicitly provided. Return error if
+ * file descriptor is not seekable, unless writing a pipable WIM
+ * was requested. */
+ wim->out_fd.fd = *(const int*)path_or_fd;
+ wim->out_fd.offset = 0;
+ if (!filedes_is_seekable(&wim->out_fd)) {
+ ret = WIMLIB_ERR_INVALID_PARAM;
+ if (!(write_flags & WIMLIB_WRITE_FLAG_PIPABLE))
+ goto out_restore_hdr;
+ if (write_flags & WIMLIB_WRITE_FLAG_CHECK_INTEGRITY) {
+ ERROR("Can't include integrity check when "
+ "writing pipable WIM to pipe!");
+ goto out_restore_hdr;
+ }
+ }
+
+ } else {
+ /* Filename of WIM to write was provided; open file descriptor
+ * to it. */
+ ret = open_wim_writable(wim, (const tchar*)path_or_fd,
+ O_TRUNC | O_CREAT | O_RDWR);
+ if (ret)
+ goto out_restore_hdr;
+ }
+
+ /* Write initial header. This is merely a "dummy" header since it
+ * doesn't have all the information yet, so it will be overwritten later
+ * (unless writing a pipable WIM). */
+ if (!(write_flags & WIMLIB_WRITE_FLAG_PIPABLE))
+ wim->hdr.flags |= WIM_HDR_FLAG_WRITE_IN_PROGRESS;
+ ret = write_wim_header(&wim->hdr, &wim->out_fd);
+ wim->hdr.flags &= ~WIM_HDR_FLAG_WRITE_IN_PROGRESS;
+ if (ret)
+ goto out_restore_hdr;
+
+ if (stream_list_override) {
+ struct wim_lookup_table_entry *lte;
+ INIT_LIST_HEAD(<_stream_list_override);
+ list_for_each_entry(lte, stream_list_override,
+ write_streams_list)
+ {
+ list_add_tail(<e->lookup_table_list,
+ <_stream_list_override);
+ }
+ }
+
+ /* Write metadata resources and streams. */
+ if (!(write_flags & WIMLIB_WRITE_FLAG_PIPABLE)) {
+ /* Default case: create a normal (non-pipable) WIM. */
+ ret = write_wim_streams(wim, image, write_flags, num_threads,
+ progress_func, stream_list_override);
+ if (ret)
+ goto out_restore_hdr;
+
+ ret = write_wim_metadata_resources(wim, image, write_flags,
+ progress_func);
+ if (ret)
+ goto out_restore_hdr;
+ } else {
+ /* Non-default case: create pipable WIM. */
+ ret = write_pipable_wim(wim, image, write_flags, num_threads,
+ progress_func, stream_list_override);
+ if (ret)
+ goto out_restore_hdr;
+ write_flags |= WIMLIB_WRITE_FLAG_HEADER_AT_END;
+ }
+
+ if (stream_list_override)
+ stream_list_override = <_stream_list_override;
+
+ /* Write lookup table, XML data, and (optional) integrity table. */
+ ret = finish_write(wim, image, write_flags, progress_func,
+ stream_list_override);
+out_restore_hdr:
+ memcpy(&wim->hdr, &hdr_save, sizeof(struct wim_header));
+ close_wim_writable(wim, write_flags);
+ return ret;
+}
+
+/* Write a standalone WIM to a file or file descriptor. */
+static int
+write_standalone_wim(WIMStruct *wim, const void *path_or_fd,
+ int image, int write_flags, unsigned num_threads,
+ wimlib_progress_func_t progress_func)
+{
+ return write_wim_part(wim, path_or_fd, image, write_flags,
+ num_threads, progress_func, 1, 1, NULL, NULL);
+}
+
+/* API function documented in wimlib.h */
+WIMLIBAPI int
+wimlib_write(WIMStruct *wim, const tchar *path,
+ int image, int write_flags, unsigned num_threads,
+ wimlib_progress_func_t progress_func)
+{
+ if (!path)
+ return WIMLIB_ERR_INVALID_PARAM;
+
+ write_flags &= WIMLIB_WRITE_MASK_PUBLIC;
+
+ return write_standalone_wim(wim, path, image, write_flags,
+ num_threads, progress_func);
+}
+
+/* API function documented in wimlib.h */
+WIMLIBAPI int
+wimlib_write_to_fd(WIMStruct *wim, int fd,
+ int image, int write_flags, unsigned num_threads,
+ wimlib_progress_func_t progress_func)
+{
+ if (fd < 0)
+ return WIMLIB_ERR_INVALID_PARAM;
+
+ write_flags &= WIMLIB_WRITE_MASK_PUBLIC;
+ write_flags |= WIMLIB_WRITE_FLAG_FILE_DESCRIPTOR;
+
+ return write_standalone_wim(wim, &fd, image, write_flags,
+ num_threads, progress_func);
+}
+
+static bool
+any_images_modified(WIMStruct *wim)
+{
+ for (int i = 0; i < wim->hdr.image_count; i++)
+ if (wim->image_metadata[i]->modified)
+ return true;
+ return false;
+}
+
+static int
+check_resource_offset(struct wim_lookup_table_entry *lte, void *_wim)
+{
+ const WIMStruct *wim = _wim;
+ off_t end_offset = *(const off_t*)wim->private;
+
+ if (lte->resource_location == RESOURCE_IN_WIM && lte->wim == wim &&
+ lte->resource_entry.offset + lte->resource_entry.size > end_offset)
+ return WIMLIB_ERR_RESOURCE_ORDER;
+ return 0;
+}
+
+/* Make sure no file or metadata resources are located after the XML data (or
+ * integrity table if present)--- otherwise we can't safely overwrite the WIM in
+ * place and we return WIMLIB_ERR_RESOURCE_ORDER. */
+static int
+check_resource_offsets(WIMStruct *wim, off_t end_offset)
+{
+ int ret;
+ unsigned i;
+
+ wim->private = &end_offset;
+ ret = for_lookup_table_entry(wim->lookup_table, check_resource_offset, wim);
+ if (ret)
+ return ret;
+
+ for (i = 0; i < wim->hdr.image_count; i++) {
+ ret = check_resource_offset(wim->image_metadata[i]->metadata_lte, wim);
+ if (ret)
+ return ret;
+ }
+ return 0;
+}
+
+/*
+ * Overwrite a WIM, possibly appending streams to it.
+ *
+ * A WIM looks like (or is supposed to look like) the following:
+ *
+ * Header (212 bytes)
+ * Streams and metadata resources (variable size)
+ * Lookup table (variable size)
+ * XML data (variable size)
+ * Integrity table (optional) (variable size)
+ *
+ * If we are not adding any streams or metadata resources, the lookup table is
+ * unchanged--- so we only need to overwrite the XML data, integrity table, and
+ * header. This operation is potentially unsafe if the program is abruptly
+ * terminated while the XML data or integrity table are being overwritten, but
+ * before the new header has been written. To partially alleviate this problem,
+ * a special flag (WIMLIB_WRITE_FLAG_CHECKPOINT_AFTER_XML) is passed to
+ * finish_write() to cause a temporary WIM header to be written after the XML
+ * data has been written. This may prevent the WIM from becoming corrupted if
+ * the program is terminated while the integrity table is being calculated (but
+ * no guarantees, due to write re-ordering...).
+ *
+ * If we are adding new streams or images (metadata resources), the lookup table
+ * needs to be changed, and those streams need to be written. In this case, we
+ * try to perform a safe update of the WIM file by writing the streams *after*
+ * the end of the previous WIM, then writing the new lookup table, XML data, and
+ * (optionally) integrity table following the new streams. This will produce a
+ * layout like the following:
+ *
+ * Header (212 bytes)
+ * (OLD) Streams and metadata resources (variable size)
+ * (OLD) Lookup table (variable size)
+ * (OLD) XML data (variable size)
+ * (OLD) Integrity table (optional) (variable size)
+ * (NEW) Streams and metadata resources (variable size)
+ * (NEW) Lookup table (variable size)
+ * (NEW) XML data (variable size)
+ * (NEW) Integrity table (optional) (variable size)
+ *
+ * At all points, the WIM is valid as nothing points to the new data yet. Then,
+ * the header is overwritten to point to the new lookup table, XML data, and
+ * integrity table, to produce the following layout:
+ *
+ * Header (212 bytes)
+ * Streams and metadata resources (variable size)
+ * Nothing (variable size)
+ * More Streams and metadata resources (variable size)
+ * Lookup table (variable size)
+ * XML data (variable size)
+ * Integrity table (optional) (variable size)
+ *
+ * This method allows an image to be appended to a large WIM very quickly, and
+ * is is crash-safe except in the case of write re-ordering, but the
+ * disadvantage is that a small hole is left in the WIM where the old lookup
+ * table, xml data, and integrity table were. (These usually only take up a
+ * small amount of space compared to the streams, however.)
+ */
+static int
+overwrite_wim_inplace(WIMStruct *wim, int write_flags,
+ unsigned num_threads,
+ wimlib_progress_func_t progress_func)
+{
+ int ret;
+ struct list_head stream_list;
+ off_t old_wim_end;
+ u64 old_lookup_table_end, old_xml_begin, old_xml_end;
+
+
+ DEBUG("Overwriting `%"TS"' in-place", wim->filename);
+
+ /* Set default integrity flag. */
+ if (!(write_flags & (WIMLIB_WRITE_FLAG_CHECK_INTEGRITY |
+ WIMLIB_WRITE_FLAG_NO_CHECK_INTEGRITY)))
+ if (wim_has_integrity_table(wim))
+ write_flags |= WIMLIB_WRITE_FLAG_CHECK_INTEGRITY;
+
+ /* Set additional flags for overwrite. */
+ write_flags |= WIMLIB_WRITE_FLAG_OVERWRITE |
+ WIMLIB_WRITE_FLAG_STREAMS_OK;
+
+ /* Make sure that the integrity table (if present) is after the XML
+ * data, and that there are no stream resources, metadata resources, or
+ * lookup tables after the XML data. Otherwise, these data would be
+ * overwritten. */
+ old_xml_begin = wim->hdr.xml_res_entry.offset;
+ old_xml_end = old_xml_begin + wim->hdr.xml_res_entry.size;
+ old_lookup_table_end = wim->hdr.lookup_table_res_entry.offset +
+ wim->hdr.lookup_table_res_entry.size;
+ if (wim->hdr.integrity.offset != 0 && wim->hdr.integrity.offset < old_xml_end) {
+ WARNING("Didn't expect the integrity table to be before the XML data");
+ return WIMLIB_ERR_RESOURCE_ORDER;
+ }
+
+ if (old_lookup_table_end > old_xml_begin) {
+ WARNING("Didn't expect the lookup table to be after the XML data");
+ return WIMLIB_ERR_RESOURCE_ORDER;
+ }
+
+ /* Set @old_wim_end, which indicates the point beyond which we don't
+ * allow any file and metadata resources to appear without returning
+ * WIMLIB_ERR_RESOURCE_ORDER (due to the fact that we would otherwise
+ * overwrite these resources). */
+ if (!wim->deletion_occurred && !any_images_modified(wim)) {
+ /* If no images have been modified and no images have been
+ * deleted, a new lookup table does not need to be written. We
+ * shall write the new XML data and optional integrity table
+ * immediately after the lookup table. Note that this may
+ * overwrite an existing integrity table. */
+ DEBUG("Skipping writing lookup table "
+ "(no images modified or deleted)");
+ old_wim_end = old_lookup_table_end;
+ write_flags |= WIMLIB_WRITE_FLAG_NO_LOOKUP_TABLE |
+ WIMLIB_WRITE_FLAG_CHECKPOINT_AFTER_XML;
+ } else if (wim->hdr.integrity.offset) {
+ /* Old WIM has an integrity table; begin writing new streams
+ * after it. */
+ old_wim_end = wim->hdr.integrity.offset + wim->hdr.integrity.size;
+ } else {
+ /* No existing integrity table; begin writing new streams after
+ * the old XML data. */
+ old_wim_end = old_xml_end;
+ }
+
+ ret = check_resource_offsets(wim, old_wim_end);
+ if (ret)
+ return ret;
+
+ ret = prepare_stream_list(wim, WIMLIB_ALL_IMAGES, write_flags,
+ &stream_list);
+ if (ret)
+ return ret;
+
+ ret = open_wim_writable(wim, wim->filename, O_RDWR);
+ if (ret)
+ return ret;
+
+ ret = lock_wim(wim, wim->out_fd.fd);
+ if (ret) {
+ close_wim_writable(wim, write_flags);
+ return ret;
+ }
+
+ /* Set WIM_HDR_FLAG_WRITE_IN_PROGRESS flag in header. */
+ ret = write_wim_header_flags(wim->hdr.flags | WIM_HDR_FLAG_WRITE_IN_PROGRESS,
+ &wim->out_fd);
+ if (ret) {
+ ERROR_WITH_ERRNO("Error updating WIM header flags");
+ close_wim_writable(wim, write_flags);
+ goto out_unlock_wim;
+ }
+
+ if (filedes_seek(&wim->out_fd, old_wim_end) == -1) {
+ ERROR_WITH_ERRNO("Can't seek to end of WIM");
+ close_wim_writable(wim, write_flags);
+ ret = WIMLIB_ERR_WRITE;
+ goto out_unlock_wim;
+ }
+
+ ret = write_stream_list(&stream_list,
+ wim->lookup_table,
+ &wim->out_fd,
+ wim->compression_type,
+ write_flags,
+ num_threads,
+ progress_func);
+ if (ret)
+ goto out_truncate;
+
+ ret = write_wim_metadata_resources(wim, WIMLIB_ALL_IMAGES,
+ write_flags, progress_func);
+ if (ret)
+ goto out_truncate;
+
+ write_flags |= WIMLIB_WRITE_FLAG_REUSE_INTEGRITY_TABLE;
+ ret = finish_write(wim, WIMLIB_ALL_IMAGES, write_flags,
+ progress_func, NULL);
+out_truncate:
+ close_wim_writable(wim, write_flags);
+ if (ret && !(write_flags & WIMLIB_WRITE_FLAG_NO_LOOKUP_TABLE)) {
+ WARNING("Truncating `%"TS"' to its original size (%"PRIu64" bytes)",
+ wim->filename, old_wim_end);
+ /* Return value of truncate() is ignored because this is already
+ * an error path. */
+ (void)ttruncate(wim->filename, old_wim_end);
+ }
+out_unlock_wim:
+ wim->wim_locked = 0;
+ return ret;
+}
+
+static int
+overwrite_wim_via_tmpfile(WIMStruct *wim, int write_flags,
+ unsigned num_threads,
+ wimlib_progress_func_t progress_func)
+{
+ size_t wim_name_len;
+ int ret;
+
+ DEBUG("Overwriting `%"TS"' via a temporary file", wim->filename);
+
+ /* Write the WIM to a temporary file in the same directory as the
+ * original WIM. */
+ wim_name_len = tstrlen(wim->filename);
+ tchar tmpfile[wim_name_len + 10];
+ tmemcpy(tmpfile, wim->filename, wim_name_len);
+ randomize_char_array_with_alnum(tmpfile + wim_name_len, 9);
+ tmpfile[wim_name_len + 9] = T('\0');
+
+ ret = wimlib_write(wim, tmpfile, WIMLIB_ALL_IMAGES,
+ write_flags | WIMLIB_WRITE_FLAG_FSYNC,
+ num_threads, progress_func);
+ if (ret)
+ goto out_unlink;
+
+ close_wim(wim);
+
+ DEBUG("Renaming `%"TS"' to `%"TS"'", tmpfile, wim->filename);
+ /* Rename the new file to the old file .*/
+ if (trename(tmpfile, wim->filename) != 0) {
+ ERROR_WITH_ERRNO("Failed to rename `%"TS"' to `%"TS"'",
+ tmpfile, wim->filename);
+ ret = WIMLIB_ERR_RENAME;
+ goto out_unlink;
+ }
+
+ if (progress_func) {
+ union wimlib_progress_info progress;
+ progress.rename.from = tmpfile;
+ progress.rename.to = wim->filename;
+ progress_func(WIMLIB_PROGRESS_MSG_RENAME, &progress);
+ }
+ return 0;
+
+out_unlink:
+ /* Remove temporary file. */
+ tunlink(tmpfile);
+ return ret;
+}
+
+/* API function documented in wimlib.h */
+WIMLIBAPI int
+wimlib_overwrite(WIMStruct *wim, int write_flags,
+ unsigned num_threads,
+ wimlib_progress_func_t progress_func)
+{
+ int ret;
+ u32 orig_hdr_flags;
+
+ write_flags &= WIMLIB_WRITE_MASK_PUBLIC;
+
+ if (write_flags & WIMLIB_WRITE_FLAG_FILE_DESCRIPTOR)
+ return WIMLIB_ERR_INVALID_PARAM;
+
+ if (!wim->filename)
+ return WIMLIB_ERR_NO_FILENAME;
+
+ orig_hdr_flags = wim->hdr.flags;
+ if (write_flags & WIMLIB_WRITE_FLAG_IGNORE_READONLY_FLAG)
+ wim->hdr.flags &= ~WIM_HDR_FLAG_READONLY;
+ ret = can_modify_wim(wim);
+ wim->hdr.flags = orig_hdr_flags;
+ if (ret)
+ return ret;
+
+ if ((!wim->deletion_occurred || (write_flags & WIMLIB_WRITE_FLAG_SOFT_DELETE))
+ && !(write_flags & (WIMLIB_WRITE_FLAG_REBUILD |
+ WIMLIB_WRITE_FLAG_PIPABLE))
+ && !(wim_is_pipable(wim)))
+ {
+ ret = overwrite_wim_inplace(wim, write_flags, num_threads,
+ progress_func);
+ if (ret != WIMLIB_ERR_RESOURCE_ORDER)
+ return ret;
+ WARNING("Falling back to re-building entire WIM");
+ }
+ return overwrite_wim_via_tmpfile(wim, write_flags, num_threads,
+ progress_func);