X-Git-Url: https://wimlib.net/git/?p=wimlib;a=blobdiff_plain;f=src%2Fextract.c;h=9feb7a0e6a718d563a2fc3ca6c9d045ed170d849;hp=1907e699315e16e7c94029af63c4872b2e887af8;hb=a6e50e8eb32035d44c94fd63bfae6c3de7481055;hpb=4377b51bd25d329e2f2c68772385f62e9c867b5c diff --git a/src/extract.c b/src/extract.c index 1907e699..9feb7a0e 100644 --- a/src/extract.c +++ b/src/extract.c @@ -165,7 +165,7 @@ ref_stream_to_extract(struct wim_lookup_table_entry *lte, lte_dentries = REALLOC(prev_lte_dentries, alloc_lte_dentries * sizeof(lte_dentries[0])); - if (!lte_dentries) + if (lte_dentries == NULL) return WIMLIB_ERR_NOMEM; if (prev_lte_dentries == NULL) { memcpy(lte_dentries, @@ -534,10 +534,10 @@ error: * This function operates slightly differently depending on whether @lte_spec is * NULL or not. When @lte_spec is NULL, the behavior is to extract the default * file contents (unnamed stream), and, if named data streams are supported in - * the extract mode and volume, any named data streams. When @lte_spec is NULL, - * the behavior is to extract only all copies of the stream @lte_spec, and in - * addition use @lte_spec to set the reparse data or create the symbolic link if - * appropriate. + * the extract mode and volume, any named data streams. When @lte_spec is not + * NULL, the behavior is to extract only all copies of the stream @lte_spec, and + * in addition use @lte_spec to set the reparse data or create the symbolic link + * if appropriate. * * @path * Path to file to extract (as can be passed to apply_operations @@ -1202,23 +1202,50 @@ dentry_extract(struct wim_dentry *dentry, void *_ctx) return extract_streams(path, ctx, dentry, NULL, NULL); } +/* Creates a temporary file opened for writing. The open file descriptor is + * returned in @fd_ret and its name is returned in @name_ret (dynamically + * allocated). */ +static int +create_temporary_file(struct filedes *fd_ret, tchar **name_ret) +{ + tchar *name; + int raw_fd; + +retry: + name = ttempnam(NULL, T("wimlib")); + if (name == NULL) { + ERROR_WITH_ERRNO("Failed to create temporary filename"); + return WIMLIB_ERR_NOMEM; + } + + raw_fd = topen(name, O_WRONLY | O_CREAT | O_EXCL | O_BINARY, 0600); + + if (raw_fd < 0) { + if (errno == EEXIST) { + FREE(name); + goto retry; + } + ERROR_WITH_ERRNO("Failed to open temporary file \"%"TS"\"", name); + FREE(name); + return WIMLIB_ERR_OPEN; + } + + filedes_init(fd_ret, raw_fd); + *name_ret = name; + return 0; +} + /* Extract all instances of the stream @lte that are being extracted in this - * call of extract_tree(). @can_seek specifies whether the WIM file descriptor - * is seekable or not (e.g. is a pipe). If not and the stream needs to be - * extracted multiple times, it is extracted to a temporary file first. - * - * This is intended for use with sequential extraction of a WIM image - * (WIMLIB_EXTRACT_FLAG_SEQUENTIAL specified). */ + * call of extract_tree(), but actually read the stream data from @lte_override. + */ static int extract_stream_instances(struct wim_lookup_table_entry *lte, - struct apply_ctx *ctx, bool can_seek) + struct wim_lookup_table_entry *lte_override, + struct apply_ctx *ctx) { struct wim_dentry **lte_dentries; - struct wim_lookup_table_entry *lte_tmp = NULL; - struct wim_lookup_table_entry *lte_override; - tchar *stream_tmp_filename = NULL; tchar path[ctx->ops->path_max]; - unsigned i; + size_t i; int ret; if (lte->out_refcnt <= ARRAY_LEN(lte->inline_lte_dentries)) @@ -1226,49 +1253,6 @@ extract_stream_instances(struct wim_lookup_table_entry *lte, else lte_dentries = lte->lte_dentries; - if (likely(can_seek || lte->out_refcnt < 2)) { - lte_override = lte; - } else { - /* Need to extract stream to temporary file. */ - struct filedes fd; - int raw_fd; - - stream_tmp_filename = ttempnam(NULL, T("wimlib")); - if (!stream_tmp_filename) { - ERROR_WITH_ERRNO("Failed to create temporary filename"); - ret = WIMLIB_ERR_OPEN; - goto out; - } - - lte_tmp = memdup(lte, sizeof(struct wim_lookup_table_entry)); - if (!lte_tmp) { - ret = WIMLIB_ERR_NOMEM; - goto out_free_stream_tmp_filename; - } - lte_tmp->resource_location = RESOURCE_IN_FILE_ON_DISK; - lte_tmp->file_on_disk = stream_tmp_filename; - lte_override = lte_tmp; - - raw_fd = topen(stream_tmp_filename, - O_WRONLY | O_CREAT | O_TRUNC | O_BINARY, 0600); - if (raw_fd < 0) { - ERROR_WITH_ERRNO("Failed to open temporary file"); - ret = WIMLIB_ERR_OPEN; - goto out_free_lte_tmp; - } - filedes_init(&fd, raw_fd); - ret = extract_stream_to_fd(lte, &fd, lte->size); - if (filedes_close(&fd) && !ret) - ret = WIMLIB_ERR_WRITE; - if (ret) - goto out_unlink_stream_tmp_file; - } - - /* Extract all instances of the stream, reading either from the stream - * in the WIM file or from the temporary file containing the stream. - * dentry->tmp_flag is used to ensure that each dentry is processed only - * once regardless of how many times this stream appears in the streams - * of the corresponding inode. */ for (i = 0; i < lte->out_refcnt; i++) { struct wim_dentry *dentry = lte_dentries[i]; @@ -1276,8 +1260,7 @@ extract_stream_instances(struct wim_lookup_table_entry *lte, continue; if (!build_extraction_path(path, dentry, ctx)) continue; - ret = extract_streams(path, ctx, dentry, - lte, lte_override); + ret = extract_streams(path, ctx, dentry, lte, lte_override); if (ret) goto out_clear_tmp_flags; dentry->tmp_flag = 1; @@ -1286,38 +1269,138 @@ extract_stream_instances(struct wim_lookup_table_entry *lte, out_clear_tmp_flags: for (i = 0; i < lte->out_refcnt; i++) lte_dentries[i]->tmp_flag = 0; -out_unlink_stream_tmp_file: - if (stream_tmp_filename) - tunlink(stream_tmp_filename); -out_free_lte_tmp: - FREE(lte_tmp); -out_free_stream_tmp_filename: - FREE(stream_tmp_filename); -out: + return ret; +} + +/* Determine whether the specified stream needs to be extracted to a temporary + * file or not. + * + * @lte->out_refcnt specifies the number of instances of this stream that must + * be extracted. + * + * @is_partial_res is %true if this stream is just one of multiple in a single + * WIM resource being extracted. */ +static bool +need_tmpfile_to_extract(struct wim_lookup_table_entry *lte, + bool is_partial_res) +{ + /* Temporary file is always required when reading a partial resource, + * since in that case we retrieve all the contained streams in one pass. + * */ + if (is_partial_res) + return true; + + /* Otherwise we don't need a temporary file if only a single instance of + * the stream is needed. */ + if (lte->out_refcnt == 1) + return false; + + wimlib_assert(lte->out_refcnt >= 2); + + /* We also don't need a temporary file if random access to the stream is + * allowed. */ + if (lte->resource_location != RESOURCE_IN_WIM || + filedes_is_seekable(<e->rspec->wim->in_fd)) + return false; + + return true; +} + +static int +begin_extract_stream_to_tmpfile(struct wim_lookup_table_entry *lte, + bool is_partial_res, + void *_ctx) +{ + struct apply_ctx *ctx = _ctx; + int ret; + + if (!need_tmpfile_to_extract(lte, is_partial_res)) { + DEBUG("Temporary file not needed " + "for stream (size=%"PRIu64")", lte->size); + ret = extract_stream_instances(lte, lte, ctx); + if (ret) + return ret; + + return BEGIN_STREAM_STATUS_SKIP_STREAM; + } + + DEBUG("Temporary file needed for stream (size=%"PRIu64")", lte->size); + return create_temporary_file(&ctx->tmpfile_fd, &ctx->tmpfile_name); +} + +static int +end_extract_stream_to_tmpfile(struct wim_lookup_table_entry *lte, + int status, void *_ctx) +{ + struct apply_ctx *ctx = _ctx; + struct wim_lookup_table_entry lte_override; + int ret; + int errno_save = errno; + + ret = filedes_close(&ctx->tmpfile_fd); + + if (status) { + ret = status; + errno = errno_save; + goto out_delete_tmpfile; + } + + if (ret) { + ERROR_WITH_ERRNO("Error writing temporary file %"TS, ctx->tmpfile_name); + ret = WIMLIB_ERR_WRITE; + goto out_delete_tmpfile; + } + + /* Now that a full stream has been extracted to a temporary file, + * extract all instances of it to the actual target. */ + + memcpy(<e_override, lte, sizeof(struct wim_lookup_table_entry)); + lte_override.resource_location = RESOURCE_IN_FILE_ON_DISK; + lte_override.file_on_disk = ctx->tmpfile_name; + + ret = extract_stream_instances(lte, <e_override, ctx); + +out_delete_tmpfile: + errno_save = errno; + tunlink(ctx->tmpfile_name); + FREE(ctx->tmpfile_name); + errno = errno_save; return ret; } /* Extracts a list of streams (ctx.stream_list), assuming that the directory * structure and empty files were already created. This relies on the * per-`struct wim_lookup_table_entry' list of dentries that reference each - * stream that was constructed earlier. Streams are extracted exactly in the - * order of the stream list; however, unless the WIM's file descriptor is - * detected to be non-seekable, streams may be read from the WIM file more than - * one time if multiple copies need to be extracted. */ + * stream that was constructed earlier. */ static int extract_stream_list(struct apply_ctx *ctx) { - struct wim_lookup_table_entry *lte; - bool can_seek; - int ret; + if (ctx->extract_flags & WIMLIB_EXTRACT_FLAG_SEQUENTIAL) { + /* Sequential extraction: read the streams in the order in which + * they appear in the WIM file. */ + struct read_stream_list_callbacks cbs = { + .begin_stream = begin_extract_stream_to_tmpfile, + .begin_stream_ctx = ctx, + .consume_chunk = extract_chunk_to_fd, + .consume_chunk_ctx = &ctx->tmpfile_fd, + .end_stream = end_extract_stream_to_tmpfile, + .end_stream_ctx = ctx, + }; + return read_stream_list(&ctx->stream_list, + offsetof(struct wim_lookup_table_entry, extraction_list), + &cbs, VERIFY_STREAM_HASHES); + } else { + /* Extract the streams in unsorted order. */ + struct wim_lookup_table_entry *lte; + int ret; - can_seek = (lseek(ctx->wim->in_fd.fd, 0, SEEK_CUR) != -1); - list_for_each_entry(lte, &ctx->stream_list, extraction_list) { - ret = extract_stream_instances(lte, ctx, can_seek); - if (ret) - return ret; + list_for_each_entry(lte, &ctx->stream_list, extraction_list) { + ret = extract_stream_instances(lte, lte, ctx); + if (ret) + return ret; + } + return 0; } - return 0; } #define PWM_ALLOW_WIM_HDR 0x00001 @@ -1352,7 +1435,7 @@ read_pwm_stream_header(WIMStruct *pwm, struct wim_lookup_table_entry *lte, return 0; } - if (buf.stream_hdr.magic != PWM_STREAM_MAGIC) { + if (le64_to_cpu(buf.stream_hdr.magic) != PWM_STREAM_MAGIC) { ERROR("Data read on pipe is invalid (expected stream header)."); return WIMLIB_ERR_INVALID_PIPABLE_WIM; } @@ -1376,25 +1459,6 @@ read_error: return ret; } -static int -skip_pwm_chunk_cb(const void *chunk, size_t chunk_size, void *_ctx) -{ - return 0; -} - -/* Skip over an unneeded stream in a pipable WIM being read from a pipe. */ -static int -skip_pwm_stream(struct wim_lookup_table_entry *lte) -{ - return read_partial_wim_resource(lte, - lte->size, - skip_pwm_chunk_cb, - lte_cchunk_size(lte), - NULL, - WIMLIB_READ_RESOURCE_FLAG_RAW_CHUNKS, - 0); -} - static int extract_streams_from_pipe(struct apply_ctx *ctx) { @@ -1444,19 +1508,60 @@ extract_streams_from_pipe(struct apply_ctx *ctx) && (needed_lte = lookup_resource(lookup_table, found_lte->hash)) && (needed_lte->out_refcnt)) { - lte_unbind_wim_resource_spec(found_lte); - lte_bind_wim_resource_spec(needed_lte, rspec); + tchar *tmpfile_name = NULL; + struct wim_lookup_table_entry *lte_override; + struct wim_lookup_table_entry tmpfile_lte; + needed_lte->offset_in_res = found_lte->offset_in_res; needed_lte->flags = found_lte->flags; needed_lte->size = found_lte->size; - ret = extract_stream_instances(needed_lte, ctx, false); - lte_unbind_wim_resource_spec(needed_lte); + lte_unbind_wim_resource_spec(found_lte); + lte_bind_wim_resource_spec(needed_lte, rspec); + + if (needed_lte->out_refcnt > 1) { + + struct filedes tmpfile_fd; + + /* Extract stream to temporary file. */ + ret = create_temporary_file(&tmpfile_fd, &tmpfile_name); + if (ret) + goto out_free_found_lte; + + ret = extract_stream_to_fd(needed_lte, &tmpfile_fd, + needed_lte->size); + if (ret) { + filedes_close(&tmpfile_fd); + goto delete_tmpfile; + } + + if (filedes_close(&tmpfile_fd)) { + ERROR_WITH_ERRNO("Error writing to temporary " + "file \"%"TS"\"", tmpfile_name); + ret = WIMLIB_ERR_WRITE; + goto delete_tmpfile; + } + memcpy(&tmpfile_lte, needed_lte, + sizeof(struct wim_lookup_table_entry)); + tmpfile_lte.resource_location = RESOURCE_IN_FILE_ON_DISK; + tmpfile_lte.file_on_disk = tmpfile_name; + lte_override = &tmpfile_lte; + } else { + lte_override = needed_lte; + } + + ret = extract_stream_instances(needed_lte, lte_override, ctx); + delete_tmpfile: + lte_unbind_wim_resource_spec(needed_lte); + if (tmpfile_name) { + tunlink(tmpfile_name); + FREE(tmpfile_name); + } if (ret) goto out_free_found_lte; ctx->num_streams_remaining--; } else if (found_lte->resource_location != RESOURCE_NONEXISTENT) { - ret = skip_pwm_stream(found_lte); + ret = skip_wim_stream(found_lte); if (ret) goto out_free_found_lte; } else { @@ -2268,21 +2373,6 @@ extract_tree(WIMStruct *wim, const tchar *wim_source_path, const tchar *target, goto out_teardown_stream_list; } - /* If a sequential extraction was specified, sort the streams to be - * extracted by their position in the WIM file so that the WIM file can - * be read sequentially. */ - if ((extract_flags & (WIMLIB_EXTRACT_FLAG_SEQUENTIAL | - WIMLIB_EXTRACT_FLAG_FROM_PIPE)) - == WIMLIB_EXTRACT_FLAG_SEQUENTIAL) - { - ret = sort_stream_list_by_sequential_order( - &ctx.stream_list, - offsetof(struct wim_lookup_table_entry, - extraction_list)); - if (ret) - goto out_teardown_stream_list; - } - if (ctx.ops->realpath_works_on_nonexisting_files && ((extract_flags & WIMLIB_EXTRACT_FLAG_RPFIX) || ctx.ops->requires_realtarget_in_paths)) @@ -2920,7 +3010,7 @@ wimlib_extract_image_from_pipe(int pipe_fd, const tchar *image_num_or_name, } else { /* Metadata resource is not for the image being * extracted. Skip over it. */ - ret = skip_pwm_stream(metadata_lte); + ret = skip_wim_stream(metadata_lte); if (ret) goto out_wimlib_free; }