X-Git-Url: https://wimlib.net/git/?p=wimlib;a=blobdiff_plain;f=src%2Fresource.c;h=8d61761414c9b718a1e4b0dab9312359616711ab;hp=a2772c1c0646918085ba004082c69dc869b674b7;hb=25319f526c1922b0bfa33e1f954bb628937070b0;hpb=a21ea64188245e4928879928eaf05e60b5065840 diff --git a/src/resource.c b/src/resource.c index a2772c1c..8d617614 100644 --- a/src/resource.c +++ b/src/resource.c @@ -1,11 +1,11 @@ /* * resource.c * - * Read uncompressed and compressed metadata and file resources. + * Read uncompressed and compressed metadata and file resources from a WIM file. */ /* - * Copyright (C) 2012 Eric Biggers + * Copyright (C) 2012, 2013 Eric Biggers * * This file is part of wimlib, a library for working with WIM files. * @@ -22,12 +22,18 @@ * wimlib; if not, see http://www.gnu.org/licenses/. */ -#include "config.h" +#include "wimlib_internal.h" +#include "dentry.h" +#include "lookup_table.h" +#include "buffer_io.h" +#include "lzx.h" +#include "xpress.h" +#include "sha1.h" -#include +#include #include - -#include "dentry.h" +#include +#include #ifdef WITH_NTFS_3G #include @@ -36,19 +42,6 @@ #include #endif -#include "wimlib_internal.h" -#include "lookup_table.h" -#include "io.h" -#include "lzx.h" -#include "xpress.h" -#include "sha1.h" -#include -#include -#ifdef HAVE_ALLOCA_H -#include -#endif - - /* * Reads all or part of a compressed resource into an in-memory buffer. * @@ -84,9 +77,9 @@ static int read_compressed_resource(FILE *fp, u64 resource_compressed_size, if (len == 0) return 0; - int (*decompress)(const void *, uint, void *, uint); + int (*decompress)(const void *, unsigned, void *, unsigned); /* Set the appropriate decompress function. */ - if (resource_ctype == WIM_COMPRESSION_TYPE_LZX) + if (resource_ctype == WIMLIB_COMPRESSION_TYPE_LZX) decompress = lzx_decompress; else decompress = xpress_decompress; @@ -233,7 +226,8 @@ static int read_compressed_resource(FILE *fp, u64 resource_compressed_size, /* Calculate the sizes of the compressed chunk and of the * uncompressed chunk. */ - uint compressed_chunk_size, uncompressed_chunk_size; + unsigned compressed_chunk_size; + unsigned uncompressed_chunk_size; if (i != num_chunks - 1) { /* All the chunks except the last one in the resource * expand to WIM_CHUNK_SIZE uncompressed, and the amount @@ -285,9 +279,9 @@ static int read_compressed_resource(FILE *fp, u64 resource_compressed_size, bool is_partial_chunk = (partial_chunk_size != uncompressed_chunk_size); - DEBUG2("start_offset = %u, end_offset = %u", start_offset, - end_offset); - DEBUG2("partial_chunk_size = %u", partial_chunk_size); + DEBUG2("start_offset = %"PRIu64", end_offset = %"PRIu64"", + start_offset, end_offset); + DEBUG2("partial_chunk_size = %"PRIu64"", partial_chunk_size); /* This is undocumented, but chunks can be uncompressed. This * appears to always be the case when the compressed chunk size @@ -377,9 +371,6 @@ int read_uncompressed_resource(FILE *fp, u64 offset, u64 len, return 0; } - - - /* Reads the contents of a struct resource_entry, as represented in the on-disk * format, from the memory pointed to by @p, and fills in the fields of @entry. * A pointer to the byte after the memory read at @p is returned. */ @@ -422,6 +413,7 @@ u8 *put_resource_entry(u8 *p, const struct resource_entry *entry) return p; } +#ifdef WITH_FUSE static FILE *wim_get_fp(WIMStruct *w) { pthread_mutex_lock(&w->fp_tab_mutex); @@ -472,6 +464,7 @@ out: pthread_mutex_unlock(&w->fp_tab_mutex); return ret; } +#endif /* * Reads some data from the resource corresponding to a WIM lookup table entry. @@ -483,7 +476,7 @@ out: * * Returns zero on success, nonzero on failure. */ -int read_wim_resource(const struct lookup_table_entry *lte, u8 buf[], +int read_wim_resource(const struct wim_lookup_table_entry *lte, u8 buf[], size_t size, u64 offset, int flags) { int ctype; @@ -504,23 +497,27 @@ int read_wim_resource(const struct lookup_table_entry *lte, u8 buf[], * or uncompressed. */ wimlib_assert(lte->wim != NULL); + #ifdef WITH_FUSE if (flags & WIMLIB_RESOURCE_FLAG_MULTITHREADED) { fp = wim_get_fp(lte->wim); if (!fp) return WIMLIB_ERR_OPEN; - } else { + } else + #endif + { + wimlib_assert(!(flags & WIMLIB_RESOURCE_FLAG_MULTITHREADED)); wimlib_assert(lte->wim->fp != NULL); fp = lte->wim->fp; } ctype = wim_resource_compression_type(lte); - wimlib_assert(ctype != WIM_COMPRESSION_TYPE_NONE || + wimlib_assert(ctype != WIMLIB_COMPRESSION_TYPE_NONE || (lte->resource_entry.original_size == lte->resource_entry.size)); if ((flags & WIMLIB_RESOURCE_FLAG_RAW) - || ctype == WIM_COMPRESSION_TYPE_NONE) + || ctype == WIMLIB_COMPRESSION_TYPE_NONE) ret = read_uncompressed_resource(fp, lte->resource_entry.offset + offset, size, buf); @@ -530,18 +527,20 @@ int read_wim_resource(const struct lookup_table_entry *lte, u8 buf[], lte->resource_entry.original_size, lte->resource_entry.offset, ctype, size, offset, buf); + #ifdef WITH_FUSE if (flags & WIMLIB_RESOURCE_FLAG_MULTITHREADED) { int ret2 = wim_release_fp(lte->wim, fp); if (ret == 0) ret = ret2; } + #endif break; case RESOURCE_IN_STAGING_FILE: case RESOURCE_IN_FILE_ON_DISK: /* The resource is in some file on the external filesystem and * needs to be read uncompressed */ - wimlib_assert(lte->file_on_disk); - wimlib_assert(<e->file_on_disk == <e->staging_file_name); + wimlib_assert(lte->file_on_disk != NULL); + BUILD_BUG_ON(<e->file_on_disk != <e->staging_file_name); /* Use existing file pointer if available; otherwise open one * temporarily */ if (lte->file_on_disk_fp) { @@ -559,6 +558,13 @@ int read_wim_resource(const struct lookup_table_entry *lte, u8 buf[], if (fp != lte->file_on_disk_fp) fclose(fp); break; +#if defined(__CYGWIN__) || defined(__WIN32__) + case RESOURCE_WIN32: + wimlib_assert(lte->file_on_disk_fp != NULL); + ret = win32_read_file(lte->file_on_disk, lte->file_on_disk_fp, + offset, size, buf); + break; +#endif case RESOURCE_IN_ATTACHED_BUFFER: /* The resource is directly attached uncompressed in an * in-memory buffer. */ @@ -569,17 +575,15 @@ int read_wim_resource(const struct lookup_table_entry *lte, u8 buf[], case RESOURCE_IN_NTFS_VOLUME: wimlib_assert(lte->ntfs_loc != NULL); wimlib_assert(lte->attr != NULL); - { - if (lte->ntfs_loc->is_reparse_point) - offset += 8; - if (ntfs_attr_pread(lte->attr, offset, size, buf) != size) { - ERROR_WITH_ERRNO("Error reading NTFS attribute " - "at `%s'", - lte->ntfs_loc->path_utf8); - ret = WIMLIB_ERR_NTFS_3G; - } - break; + if (lte->ntfs_loc->is_reparse_point) + offset += 8; + if (ntfs_attr_pread(lte->attr, offset, size, buf) != size) { + ERROR_WITH_ERRNO("Error reading NTFS attribute " + "at `%s'", + lte->ntfs_loc->path_utf8); + ret = WIMLIB_ERR_NTFS_3G; } + break; #endif default: wimlib_assert(0); @@ -599,529 +603,96 @@ int read_wim_resource(const struct lookup_table_entry *lte, u8 buf[], * * Returns 0 on success; nonzero on failure. */ -int read_full_wim_resource(const struct lookup_table_entry *lte, u8 buf[], +int read_full_wim_resource(const struct wim_lookup_table_entry *lte, u8 buf[], int flags) { return read_wim_resource(lte, buf, wim_resource_size(lte), 0, flags); } -/* Chunk table that's located at the beginning of each compressed resource in - * the WIM. (This is not the on-disk format; the on-disk format just has an - * array of offsets.) */ -struct chunk_table { - off_t file_offset; - u64 num_chunks; - u64 original_resource_size; - u64 bytes_per_chunk_entry; - u64 table_disk_size; - u64 cur_offset; - u64 *cur_offset_p; - u64 offsets[0]; -}; - -/* - * Allocates and initializes a chunk table, and reserves space for it in the - * output file. - */ -static int -begin_wim_resource_chunk_tab(const struct lookup_table_entry *lte, - FILE *out_fp, - off_t file_offset, - struct chunk_table **chunk_tab_ret) -{ - u64 size = wim_resource_size(lte); - u64 num_chunks = (size + WIM_CHUNK_SIZE - 1) / WIM_CHUNK_SIZE; - size_t alloc_size = sizeof(struct chunk_table) + num_chunks * sizeof(u64); - struct chunk_table *chunk_tab = CALLOC(1, alloc_size); - int ret; - - if (!chunk_tab) { - ERROR("Failed to allocate chunk table for %"PRIu64" byte " - "resource", size); - ret = WIMLIB_ERR_NOMEM; - goto out; - } - chunk_tab->file_offset = file_offset; - chunk_tab->num_chunks = num_chunks; - chunk_tab->original_resource_size = size; - chunk_tab->bytes_per_chunk_entry = (size >= (1ULL << 32)) ? 8 : 4; - chunk_tab->table_disk_size = chunk_tab->bytes_per_chunk_entry * - (num_chunks - 1); - chunk_tab->cur_offset = 0; - chunk_tab->cur_offset_p = chunk_tab->offsets; - - if (fwrite(chunk_tab, 1, chunk_tab->table_disk_size, out_fp) != - chunk_tab->table_disk_size) { - ERROR_WITH_ERRNO("Failed to write chunk table in compressed " - "file resource"); - ret = WIMLIB_ERR_WRITE; - goto out; - } - - ret = 0; -out: - *chunk_tab_ret = chunk_tab; - return ret; -} - -/* - * Compresses a chunk of a WIM resource. - * - * @chunk: Uncompressed data of the chunk. - * @chunk_size: Size of the uncompressed chunk in bytes. - * @compressed_chunk: Pointer to output buffer of size at least - * (@chunk_size - 1) bytes. - * @compressed_chunk_len_ret: Pointer to an unsigned int into which the size - * of the compressed chunk will be - * returned. - * @ctype: Type of compression to use. Must be WIM_COMPRESSION_TYPE_LZX - * or WIM_COMPRESSION_TYPE_XPRESS. - * - * Returns zero if compressed succeeded, and nonzero if the chunk could not be - * compressed to any smaller than @chunk_size. This function cannot fail for - * any other reasons. - */ -static int compress_chunk(const u8 chunk[], unsigned chunk_size, - u8 compressed_chunk[], - unsigned *compressed_chunk_len_ret, - int ctype) -{ - int (*compress)(const void *, unsigned, void *, unsigned *); - switch (ctype) { - case WIM_COMPRESSION_TYPE_LZX: - compress = lzx_compress; - break; - case WIM_COMPRESSION_TYPE_XPRESS: - compress = xpress_compress; - break; - default: - wimlib_assert(0); - break; - } - return (*compress)(chunk, chunk_size, compressed_chunk, - compressed_chunk_len_ret); -} - -/* - * Writes a chunk of a WIM resource to an output file. - * - * @chunk: Uncompressed data of the chunk. - * @chunk_size: Size of the chunk (<= WIM_CHUNK_SIZE) - * @out_fp: FILE * to write tho chunk to. - * @out_ctype: Compression type to use when writing the chunk (ignored if no - * chunk table provided) - * @chunk_tab: Pointer to chunk table being created. It is updated with the - * offset of the chunk we write. - * - * Returns 0 on success; nonzero on failure. - */ -static int write_wim_resource_chunk(const u8 chunk[], unsigned chunk_size, - FILE *out_fp, int out_ctype, - struct chunk_table *chunk_tab) -{ - const u8 *out_chunk; - unsigned out_chunk_size; - - wimlib_assert(chunk_size <= WIM_CHUNK_SIZE); - - if (!chunk_tab) { - out_chunk = chunk; - out_chunk_size = chunk_size; - } else { - u8 *compressed_chunk = alloca(chunk_size); - int ret; - - ret = compress_chunk(chunk, chunk_size, compressed_chunk, - &out_chunk_size, out_ctype); - if (ret == 0) { - out_chunk = compressed_chunk; - } else { - out_chunk = chunk; - out_chunk_size = chunk_size; - } - *chunk_tab->cur_offset_p++ = chunk_tab->cur_offset; - chunk_tab->cur_offset += out_chunk_size; - } - - if (fwrite(out_chunk, 1, out_chunk_size, out_fp) != out_chunk_size) { - ERROR_WITH_ERRNO("Failed to write WIM resource chunk"); - return WIMLIB_ERR_WRITE; - } - return 0; -} - -/* - * Finishes a WIM chunk tale and writes it to the output file at the correct - * offset. - * - * The final size of the full compressed resource is returned in the - * @compressed_size_p. - */ -static int -finish_wim_resource_chunk_tab(struct chunk_table *chunk_tab, - FILE *out_fp, u64 *compressed_size_p) -{ - size_t bytes_written; - if (fseeko(out_fp, chunk_tab->file_offset, SEEK_SET) != 0) { - ERROR_WITH_ERRNO("Failed to seek to byte %"PRIu64" of output " - "WIM file", chunk_tab->file_offset); - return WIMLIB_ERR_WRITE; - } - - if (chunk_tab->bytes_per_chunk_entry == 8) { - array_cpu_to_le64(chunk_tab->offsets, chunk_tab->num_chunks); - } else { - for (u64 i = 0; i < chunk_tab->num_chunks; i++) - ((u32*)chunk_tab->offsets)[i] = - cpu_to_le32(chunk_tab->offsets[i]); - } - bytes_written = fwrite((u8*)chunk_tab->offsets + - chunk_tab->bytes_per_chunk_entry, - 1, chunk_tab->table_disk_size, out_fp); - if (bytes_written != chunk_tab->table_disk_size) { - ERROR_WITH_ERRNO("Failed to write chunk table in compressed " - "file resource"); - return WIMLIB_ERR_WRITE; - } - if (fseeko(out_fp, 0, SEEK_END) != 0) { - ERROR_WITH_ERRNO("Failed to seek to end of output WIM file"); - return WIMLIB_ERR_WRITE; - } - *compressed_size_p = chunk_tab->cur_offset + chunk_tab->table_disk_size; - return 0; -} - -/* - * Writes a WIM resource to a FILE * opened for writing. The resource may be - * written uncompressed or compressed depending on the @out_ctype parameter. - * - * If by chance the resource compresses to more than the original size (this may - * happen with random data or files than are pre-compressed), the resource is - * instead written uncompressed (and this is reflected in the @out_res_entry by - * removing the WIM_RESHDR_FLAG_COMPRESSED flag). - * - * @lte: The lookup table entry for the WIM resource. - * @out_fp: The FILE * to write the resource to. - * @out_ctype: The compression type of the resource to write. Note: if this is - * the same as the compression type of the WIM resource we - * need to read, we simply copy the data (i.e. we do not - * uncompress it, then compress it again). - * @out_res_entry: If non-NULL, a resource entry that is filled in with the - * offset, original size, compressed size, and compression flag - * of the output resource. - * - * Returns 0 on success; nonzero on failure. - */ -static int write_wim_resource(struct lookup_table_entry *lte, - FILE *out_fp, int out_ctype, - struct resource_entry *out_res_entry, - int flags) -{ - u64 bytes_remaining; - u64 original_size; - u64 old_compressed_size; - u64 new_compressed_size; - u64 offset; - int ret; - struct chunk_table *chunk_tab = NULL; - bool raw; - off_t file_offset; -#ifdef WITH_NTFS_3G - ntfs_inode *ni = NULL; -#endif - - wimlib_assert(lte); - - /* Original size of the resource */ - original_size = wim_resource_size(lte); - - /* Compressed size of the resource (as it exists now) */ - old_compressed_size = wim_resource_compressed_size(lte); - - /* Current offset in output file */ - file_offset = ftello(out_fp); - if (file_offset == -1) { - ERROR_WITH_ERRNO("Failed to get offset in output " - "stream"); - return WIMLIB_ERR_WRITE; - } - - /* Are the compression types the same? If so, do a raw copy (copy - * without decompressing and recompressing the data). */ - raw = (wim_resource_compression_type(lte) == out_ctype - && out_ctype != WIM_COMPRESSION_TYPE_NONE); - - if (raw) { - flags |= WIMLIB_RESOURCE_FLAG_RAW; - bytes_remaining = old_compressed_size; - } else { - flags &= ~WIMLIB_RESOURCE_FLAG_RAW; - bytes_remaining = original_size; - } - - /* Empty resource; nothing needs to be done, so just return success. */ - if (bytes_remaining == 0) - return 0; - - /* Buffer for reading chunks for the resource */ - u8 buf[min(WIM_CHUNK_SIZE, bytes_remaining)]; - - /* If we are writing a compressed resource and not doing a raw copy, we - * need to initialize the chunk table */ - if (out_ctype != WIM_COMPRESSION_TYPE_NONE && !raw) { - ret = begin_wim_resource_chunk_tab(lte, out_fp, file_offset, - &chunk_tab); - if (ret != 0) - goto out; - } - - /* If the WIM resource is in an external file, open a FILE * to it so we - * don't have to open a temporary one in read_wim_resource() for each - * chunk. */ - if (lte->resource_location == RESOURCE_IN_FILE_ON_DISK - && !lte->file_on_disk_fp) - { - wimlib_assert(lte->file_on_disk); - lte->file_on_disk_fp = fopen(lte->file_on_disk, "rb"); - if (!lte->file_on_disk_fp) { - ERROR_WITH_ERRNO("Failed to open the file `%s' for " - "reading", lte->file_on_disk); - ret = WIMLIB_ERR_OPEN; - goto out; - } - } -#ifdef WITH_NTFS_3G - else if (lte->resource_location == RESOURCE_IN_NTFS_VOLUME - && !lte->attr) - { - struct ntfs_location *loc = lte->ntfs_loc; - wimlib_assert(loc); - ni = ntfs_pathname_to_inode(*loc->ntfs_vol_p, NULL, loc->path_utf8); - if (!ni) { - ERROR_WITH_ERRNO("Failed to open inode `%s' in NTFS " - "volume", loc->path_utf8); - ret = WIMLIB_ERR_NTFS_3G; - goto out; - } - lte->attr = ntfs_attr_open(ni, - loc->is_reparse_point ? AT_REPARSE_POINT : AT_DATA, - (ntfschar*)loc->stream_name_utf16, - loc->stream_name_utf16_num_chars); - if (!lte->attr) { - ERROR_WITH_ERRNO("Failed to open attribute of `%s' in " - "NTFS volume", loc->path_utf8); - ret = WIMLIB_ERR_NTFS_3G; - goto out_fclose; - } - } -#endif - - /* If we aren't doing a raw copy, we will compute the SHA1 message - * digest of the resource as we read it, and verify it's the same as the - * hash given in the lookup table entry once we've finished reading the - * resource. */ - SHA_CTX ctx; - if (!raw) - sha1_init(&ctx); - - /* While there are still bytes remaining in the WIM resource, read a - * chunk of the resource, update SHA1, then write that chunk using the - * desired compression type. */ - offset = 0; - do { - u64 to_read = min(bytes_remaining, WIM_CHUNK_SIZE); - ret = read_wim_resource(lte, buf, to_read, offset, flags); - if (ret != 0) - goto out_fclose; - if (!raw) - sha1_update(&ctx, buf, to_read); - ret = write_wim_resource_chunk(buf, to_read, out_fp, - out_ctype, chunk_tab); - if (ret != 0) - goto out_fclose; - bytes_remaining -= to_read; - offset += to_read; - } while (bytes_remaining); - - /* Raw copy: The new compressed size is the same as the old compressed - * size - * - * Using WIM_COMPRESSION_TYPE_NONE: The new compressed size is the - * original size - * - * Using a different compression type: Call - * finish_wim_resource_chunk_tab() and it will provide the new - * compressed size. - */ - if (raw) { - new_compressed_size = old_compressed_size; - } else { - if (out_ctype == WIM_COMPRESSION_TYPE_NONE) - new_compressed_size = original_size; - else { - ret = finish_wim_resource_chunk_tab(chunk_tab, out_fp, - &new_compressed_size); - if (ret != 0) - goto out_fclose; - } - } - - /* Verify SHA1 message digest of the resource, unless we are doing a raw - * write (in which case we never even saw the uncompressed data). Or, - * if the hash we had before is all 0's, just re-set it to be the new - * hash. */ - if (!raw) { - u8 md[SHA1_HASH_SIZE]; - sha1_final(md, &ctx); - if (is_zero_hash(lte->hash)) { - copy_hash(lte->hash, md); - } else if (!hashes_equal(md, lte->hash)) { - ERROR("WIM resource has incorrect hash!"); - if (lte->resource_location == RESOURCE_IN_FILE_ON_DISK) { - ERROR("We were reading it from `%s'; maybe it changed " - "while we were reading it.", - lte->file_on_disk); - } - ret = WIMLIB_ERR_INVALID_RESOURCE_HASH; - goto out_fclose; - } - } - - if (!raw && new_compressed_size >= original_size && - out_ctype != WIM_COMPRESSION_TYPE_NONE) - { - /* Oops! We compressed the resource to larger than the original - * size. Write the resource uncompressed instead. */ - if (fseeko(out_fp, file_offset, SEEK_SET) != 0) { - ERROR_WITH_ERRNO("Failed to seek to byte %"PRIu64" " - "of output WIM file", file_offset); - ret = WIMLIB_ERR_WRITE; - goto out_fclose; - } - ret = write_wim_resource(lte, out_fp, WIM_COMPRESSION_TYPE_NONE, - out_res_entry, flags); - if (ret != 0) - goto out_fclose; - if (fflush(out_fp) != 0) { - ERROR_WITH_ERRNO("Failed to flush output WIM file"); - ret = WIMLIB_ERR_WRITE; - goto out_fclose; - } - if (ftruncate(fileno(out_fp), file_offset + out_res_entry->size) != 0) { - ERROR_WITH_ERRNO("Failed to truncate output WIM file"); - ret = WIMLIB_ERR_WRITE; - goto out_fclose; - } - } else { - if (out_res_entry) { - out_res_entry->size = new_compressed_size; - out_res_entry->original_size = original_size; - out_res_entry->offset = file_offset; - out_res_entry->flags = lte->resource_entry.flags - & ~WIM_RESHDR_FLAG_COMPRESSED; - if (out_ctype != WIM_COMPRESSION_TYPE_NONE) - out_res_entry->flags |= WIM_RESHDR_FLAG_COMPRESSED; - } - } - ret = 0; -out_fclose: - if (lte->resource_location == RESOURCE_IN_FILE_ON_DISK - && lte->file_on_disk_fp) { - fclose(lte->file_on_disk_fp); - lte->file_on_disk_fp = NULL; - } -#ifdef WITH_NTFS_3G - else if (lte->resource_location == RESOURCE_IN_NTFS_VOLUME) { - if (lte->attr) { - ntfs_attr_close(lte->attr); - lte->attr = NULL; - } - if (ni) - ntfs_inode_close(ni); - } -#endif -out: - FREE(chunk_tab); - return ret; -} - -/* Like write_wim_resource(), but the resource is specified by a buffer of - * uncompressed data rather a lookup table entry; also writes the SHA1 hash of - * the buffer to @hash. */ -static int write_wim_resource_from_buffer(const u8 *buf, u64 buf_size, - FILE *out_fp, int out_ctype, - struct resource_entry *out_res_entry, - u8 hash[SHA1_HASH_SIZE]) -{ - /* Set up a temporary lookup table entry to provide to - * write_wim_resource(). */ - struct lookup_table_entry lte; - int ret; - lte.resource_entry.flags = 0; - lte.resource_entry.original_size = buf_size; - lte.resource_entry.size = buf_size; - lte.resource_entry.offset = 0; - lte.resource_location = RESOURCE_IN_ATTACHED_BUFFER; - lte.attached_buffer = (u8*)buf; - - zero_out_hash(lte.hash); - ret = write_wim_resource(<e, out_fp, out_ctype, out_res_entry, 0); - if (ret != 0) - return ret; - copy_hash(hash, lte.hash); - return 0; -} - -/* - * Extracts the first @size bytes of the WIM resource specified by @lte to the - * open file descriptor @fd. +/* Extracts the first @size bytes of a WIM resource to somewhere. In the + * process, the SHA1 message digest of the resource is checked if the full + * resource is being extracted. * - * Returns 0 on success; nonzero on failure. - */ -int extract_wim_resource_to_fd(const struct lookup_table_entry *lte, int fd, - u64 size) + * @extract_chunk is a function that is called to extract each chunk of the + * resource. */ +int extract_wim_resource(const struct wim_lookup_table_entry *lte, + u64 size, + extract_chunk_func_t extract_chunk, + void *extract_chunk_arg) { u64 bytes_remaining = size; u8 buf[min(WIM_CHUNK_SIZE, bytes_remaining)]; u64 offset = 0; int ret = 0; u8 hash[SHA1_HASH_SIZE]; - + bool check_hash = (size == wim_resource_size(lte)); SHA_CTX ctx; - sha1_init(&ctx); + + if (check_hash) + sha1_init(&ctx); while (bytes_remaining) { - u64 to_read = min(bytes_remaining, WIM_CHUNK_SIZE); + u64 to_read = min(bytes_remaining, sizeof(buf)); ret = read_wim_resource(lte, buf, to_read, offset, 0); if (ret != 0) - break; - sha1_update(&ctx, buf, to_read); - if (full_write(fd, buf, to_read) < to_read) { + return ret; + if (check_hash) + sha1_update(&ctx, buf, to_read); + ret = extract_chunk(buf, to_read, offset, extract_chunk_arg); + if (ret != 0) { ERROR_WITH_ERRNO("Error extracting WIM resource"); - return WIMLIB_ERR_WRITE; + return ret; } bytes_remaining -= to_read; offset += to_read; } - sha1_final(hash, &ctx); - if (!hashes_equal(hash, lte->hash)) { - ERROR("Invalid checksum on a WIM resource " - "(detected when extracting to external file)"); - ERROR("The following WIM resource is invalid:"); - print_lookup_table_entry(lte); - return WIMLIB_ERR_INVALID_RESOURCE_HASH; + if (check_hash) { + sha1_final(hash, &ctx); + if (!hashes_equal(hash, lte->hash)) { + #ifdef ENABLE_ERROR_MESSAGES + ERROR("Invalid checksum on the following WIM resource:"); + print_lookup_table_entry(lte, stderr); + #endif + return WIMLIB_ERR_INVALID_RESOURCE_HASH; + } } return 0; } -/* - * Extracts the WIM resource specified by @lte to the open file descriptor @fd. +/* Write @n bytes from @buf to the file descriptor @fd, retrying on internupt + * and on short writes. * - * Returns 0 on success; nonzero on failure. - */ -int extract_full_wim_resource_to_fd(const struct lookup_table_entry *lte, int fd) + * Returns short count and set errno on failure. */ +static ssize_t full_write(int fd, const void *buf, size_t n) +{ + const char *p = buf; + ssize_t ret; + ssize_t total = 0; + + while (total != n) { + ret = write(fd, p, n); + if (ret < 0) { + if (errno == EINTR) + continue; + else + break; + } + total += ret; + p += ret; + } + return total; +} + +int extract_wim_chunk_to_fd(const u8 *buf, size_t len, u64 offset, void *arg) { - return extract_wim_resource_to_fd(lte, fd, wim_resource_size(lte)); + int fd = *(int*)arg; + ssize_t ret = full_write(fd, buf, len); + if (ret < len) { + ERROR_WITH_ERRNO("Error writing to file descriptor"); + return WIMLIB_ERR_WRITE; + } else { + return 0; + } } /* @@ -1132,10 +703,9 @@ int extract_full_wim_resource_to_fd(const struct lookup_table_entry *lte, int fd * The output_resource_entry, out_refcnt, and part_number fields of @lte are * updated. * - * Metadata resources are not copied (they are handled elsewhere for joining and - * splitting). + * (This function is confusing and should be refactored somehow.) */ -int copy_resource(struct lookup_table_entry *lte, void *wim) +int copy_resource(struct wim_lookup_table_entry *lte, void *wim) { WIMStruct *w = wim; int ret; @@ -1153,293 +723,3 @@ int copy_resource(struct lookup_table_entry *lte, void *wim) lte->part_number = w->hdr.part_number; return 0; } - -/* - * Writes a dentry's resources, including the main file resource as well as all - * alternate data streams, to the output file. - * - * @dentry: The dentry for the file. - * @wim_p: A pointer to the WIMStruct containing @dentry. - * - * @return zero on success, nonzero on failure. - */ -int write_dentry_resources(struct dentry *dentry, void *wim_p) -{ - WIMStruct *w = wim_p; - int ret = 0; - struct lookup_table_entry *lte; - int ctype = wimlib_get_compression_type(w); - - if (w->write_flags & WIMLIB_WRITE_FLAG_VERBOSE) { - wimlib_assert(dentry->full_path_utf8); - printf("Writing streams for `%s'\n", dentry->full_path_utf8); - } - - for (unsigned i = 0; i <= dentry->d_inode->num_ads; i++) { - lte = inode_stream_lte(dentry->d_inode, i, w->lookup_table); - if (lte && ++lte->out_refcnt == 1) { - ret = write_wim_resource(lte, w->out_fp, ctype, - <e->output_resource_entry, 0); - if (ret != 0) - break; - } - } - return ret; -} - -/* - * Reads the metadata metadata resource from the WIM file. The metadata - * resource consists of the security data, followed by the directory entry for - * the root directory, followed by all the other directory entries in the - * filesystem. The subdir_offset field of each directory entry gives the start - * of its child entries from the beginning of the metadata resource. An - * end-of-directory is signaled by a directory entry of length '0', really of - * length 8, because that's how long the 'length' field is. - * - * @fp: The FILE* for the input WIM file. - * @wim_ctype: The compression type of the WIM file. - * @imd: Pointer to the image metadata structure. Its `metadata_lte' - * member specifies the lookup table entry for the metadata - * resource. The rest of the image metadata entry will be filled - * in by this function. - * - * @return: Zero on success, nonzero on failure. - */ -int read_metadata_resource(WIMStruct *w, struct image_metadata *imd) -{ - u8 *buf; - u32 dentry_offset; - int ret; - struct dentry *dentry; - struct inode_table inode_tab; - const struct lookup_table_entry *metadata_lte; - u64 metadata_len; - u64 metadata_offset; - struct hlist_head inode_list; - - metadata_lte = imd->metadata_lte; - metadata_len = wim_resource_size(metadata_lte); - metadata_offset = metadata_lte->resource_entry.offset; - - DEBUG("Reading metadata resource: length = %"PRIu64", " - "offset = %"PRIu64"", metadata_len, metadata_offset); - - /* There is no way the metadata resource could possibly be less than (8 - * + WIM_DENTRY_DISK_SIZE) bytes, where the 8 is for security data (with - * no security descriptors) and WIM_DENTRY_DISK_SIZE is for the root - * dentry. */ - if (metadata_len < 8 + WIM_DENTRY_DISK_SIZE) { - ERROR("Expected at least %u bytes for the metadata resource", - 8 + WIM_DENTRY_DISK_SIZE); - return WIMLIB_ERR_INVALID_RESOURCE_SIZE; - } - - if (sizeof(size_t) < 8 && metadata_len > 0xffffffff) { - ERROR("Metadata resource is too large (%"PRIu64" bytes", - metadata_len); - return WIMLIB_ERR_INVALID_RESOURCE_SIZE; - } - - /* Allocate memory for the uncompressed metadata resource. */ - buf = MALLOC(metadata_len); - - if (!buf) { - ERROR("Failed to allocate %"PRIu64" bytes for uncompressed " - "metadata resource", metadata_len); - return WIMLIB_ERR_NOMEM; - } - - /* Read the metadata resource into memory. (It may be compressed.) */ - ret = read_full_wim_resource(metadata_lte, buf, 0); - if (ret != 0) - goto out_free_buf; - - DEBUG("Finished reading metadata resource into memory."); - - /* The root directory entry starts after security data, aligned on an - * 8-byte boundary within the metadata resource. - * - * The security data starts with a 4-byte integer giving its total - * length, so if we round that up to an 8-byte boundary that gives us - * the offset of the root dentry. - * - * Here we read the security data into a wim_security_data structure, - * and if successful, go ahead and calculate the offset in the metadata - * resource of the root dentry. */ - - wimlib_assert(imd->security_data == NULL); - ret = read_security_data(buf, metadata_len, &imd->security_data); - if (ret != 0) - goto out_free_buf; - - dentry_offset = (imd->security_data->total_length + 7) & ~7; - - if (dentry_offset == 0) { - ERROR("Integer overflow while reading metadata resource"); - ret = WIMLIB_ERR_INVALID_SECURITY_DATA; - goto out_free_security_data; - } - - /* Allocate memory for the root dentry and read it into memory */ - dentry = MALLOC(sizeof(struct dentry)); - if (!dentry) { - ERROR("Failed to allocate %zu bytes for root dentry", - sizeof(struct dentry)); - ret = WIMLIB_ERR_NOMEM; - goto out_free_security_data; - } - - ret = read_dentry(buf, metadata_len, dentry_offset, dentry); - - /* This is the root dentry, so set its parent to itself. */ - dentry->parent = dentry; - - if (ret != 0) - goto out_free_dentry_tree; - inode_add_dentry(dentry, dentry->d_inode); - - /* Now read the entire directory entry tree into memory. */ - DEBUG("Reading dentry tree"); - ret = read_dentry_tree(buf, metadata_len, dentry); - if (ret != 0) - goto out_free_dentry_tree; - - /* Calculate the full paths in the dentry tree. */ - DEBUG("Calculating dentry full paths"); - ret = for_dentry_in_tree(dentry, calculate_dentry_full_path, NULL); - if (ret != 0) - goto out_free_dentry_tree; - - /* Build hash table that maps hard link group IDs to dentry sets */ - DEBUG("Building link group table"); - ret = init_inode_table(&inode_tab, 9001); - if (ret != 0) - goto out_free_dentry_tree; - - for_dentry_in_tree(dentry, inode_table_insert, &inode_tab); - - DEBUG("Fixing inconsistencies in the hard link groups"); - ret = fix_inodes(&inode_tab, &inode_list); - destroy_inode_table(&inode_tab); - if (ret != 0) - goto out_free_dentry_tree; - - DEBUG("Running miscellaneous verifications on the dentry tree"); - for_lookup_table_entry(w->lookup_table, lte_zero_real_refcnt, NULL); - ret = for_dentry_in_tree(dentry, verify_dentry, w); - if (ret != 0) - goto out_free_dentry_tree; - - DEBUG("Done reading image metadata"); - - imd->root_dentry = dentry; - imd->inode_list = inode_list; - goto out_free_buf; -out_free_dentry_tree: - free_dentry_tree(dentry, NULL); -out_free_security_data: - free_security_data(imd->security_data); - imd->security_data = NULL; -out_free_buf: - FREE(buf); - return ret; -} - -/* Write the metadata resource for the current WIM image. */ -int write_metadata_resource(WIMStruct *w) -{ - u8 *buf; - u8 *p; - int ret; - u64 subdir_offset; - struct dentry *root; - struct lookup_table_entry *lte; - u64 metadata_original_size; - const struct wim_security_data *sd; - - DEBUG("Writing metadata resource for image %d", w->current_image); - - root = wim_root_dentry(w); - sd = wim_security_data(w); - - /* We do not allow the security data pointer to be NULL, although it may - * point to an empty security data with no entries. */ - wimlib_assert(root != NULL); - wimlib_assert(sd != NULL); - - /* Offset of first child of the root dentry. It's equal to: - * - The total length of the security data, rounded to the next 8-byte - * boundary, - * - plus the total length of the root dentry, - * - plus 8 bytes for an end-of-directory entry following the root - * dentry (shouldn't really be needed, but just in case...) - */ - subdir_offset = ((sd->total_length + 7) & ~7) + - dentry_correct_total_length(root) + 8; - - /* Calculate the subdirectory offsets for the entire dentry tree. */ - calculate_subdir_offsets(root, &subdir_offset); - - /* Total length of the metadata resource (uncompressed) */ - metadata_original_size = subdir_offset; - - /* Allocate a buffer to contain the uncompressed metadata resource */ - buf = MALLOC(metadata_original_size); - if (!buf) { - ERROR("Failed to allocate %"PRIu64" bytes for " - "metadata resource", metadata_original_size); - return WIMLIB_ERR_NOMEM; - } - - /* Write the security data into the resource buffer */ - p = write_security_data(sd, buf); - - /* Write the dentry tree into the resource buffer */ - p = write_dentry_tree(root, p); - - /* We MUST have exactly filled the buffer; otherwise we calculated its - * size incorrectly or wrote the data incorrectly. */ - wimlib_assert(p - buf == metadata_original_size); - - /* Get the lookup table entry for the metadata resource so we can update - * it. */ - lte = wim_metadata_lookup_table_entry(w); - - wimlib_assert(lte != NULL); - - /* Write the metadata resource to the output WIM using the proper - * compression type. The lookup table entry for the metadata resource - * is updated. */ - ret = write_wim_resource_from_buffer(buf, metadata_original_size, - w->out_fp, - wimlib_get_compression_type(w), - <e->output_resource_entry, - lte->hash); - if (ret != 0) - goto out; - - /* It's very likely the SHA1 message digest of the metadata resource - * changed, so re-insert the lookup table entry into the lookup table. - * - * We do not check for other lookup table entries having the same SHA1 - * message digest. It's possible for 2 absolutely identical images to - * be added, therefore causing 2 identical metadata resources to be in - * the WIM. However, in this case, it's expected for 2 separate lookup - * table entries to be created, even though this doesn't make a whole - * lot of sense since they will share the same SHA1 message digest. - * */ - lookup_table_unlink(w->lookup_table, lte); - lookup_table_insert(w->lookup_table, lte); - - wimlib_assert(lte->out_refcnt == 0); - lte->out_refcnt = 1; - - /* Make sure that the resource entry is written marked with the metadata - * flag. */ - lte->output_resource_entry.flags |= WIM_RESHDR_FLAG_METADATA; -out: - /* All the data has been written to the new WIM; no need for the buffer - * anymore */ - FREE(buf); - return ret; -}