X-Git-Url: https://wimlib.net/git/?p=wimlib;a=blobdiff_plain;f=src%2Fresource.c;h=d60f5476ebadd9557e948e6c7e823f5d30e536b5;hp=a1268fbf8108f97898e402141b8e57916eb42806;hb=761ec06065819eb2af9e2554813f8b87ff48f695;hpb=da2c501c4ca54063126290c2103f607e926c9989 diff --git a/src/resource.c b/src/resource.c index a1268fbf..d60f5476 100644 --- a/src/resource.c +++ b/src/resource.c @@ -1,82 +1,87 @@ /* * resource.c * - * Read uncompressed and compressed metadata and file resources. + * Read uncompressed and compressed metadata and file resources from a WIM file. */ /* - * Copyright (C) 2010 Carl Thijssen - * Copyright (C) 2012 Eric Biggers + * Copyright (C) 2012, 2013 Eric Biggers * * This file is part of wimlib, a library for working with WIM files. * * wimlib is free software; you can redistribute it and/or modify it under the - * terms of the GNU Lesser General Public License as published by the Free - * Software Foundation; either version 2.1 of the License, or (at your option) - * any later version. + * terms of the GNU General Public License as published by the Free Software + * Foundation; either version 3 of the License, or (at your option) any later + * version. * * wimlib is distributed in the hope that it will be useful, but WITHOUT ANY * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR - * A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more - * details. + * A PARTICULAR PURPOSE. See the GNU General Public License for more details. * - * You should have received a copy of the GNU Lesser General Public License - * along with wimlib; if not, see http://www.gnu.org/licenses/. + * You should have received a copy of the GNU General Public License along with + * wimlib; if not, see http://www.gnu.org/licenses/. */ -#include "wimlib_internal.h" -#include "lookup_table.h" -#include "io.h" -#include "lzx.h" -#include "xpress.h" -#include "sha1.h" -#include "dentry.h" -#include "config.h" -#include +#ifdef HAVE_CONFIG_H +# include "config.h" +#endif + +#include "wimlib.h" +#include "wimlib/dentry.h" +#include "wimlib/endianness.h" +#include "wimlib/error.h" +#include "wimlib/file_io.h" +#include "wimlib/lookup_table.h" +#include "wimlib/resource.h" +#include "wimlib/sha1.h" + +#ifdef __WIN32__ +/* for read_win32_file_prefix(), read_win32_encrypted_file_prefix() */ +# include "wimlib/win32.h" +#endif + +#ifdef WITH_NTFS_3G +/* for read_ntfs_file_prefix() */ +# include "wimlib/ntfs_3g.h" +#endif + +#ifdef HAVE_ALLOCA_H +# include +#endif #include +#include +#include +#include +#include - -/* - * Reads all or part of a compressed resource into an in-memory buffer. - * - * @fp: The FILE* for the WIM file. - * @resource_compressed_size: The compressed size of the resource. - * @resource_uncompressed_size: The uncompressed size of the resource. - * @resource_offset: The offset of the start of the resource from - * the start of the stream @fp. - * @resource_ctype: The compression type of the resource. - * @len: The number of bytes of uncompressed data to read from - * the resource. - * @offset: The offset of the bytes to read within the uncompressed - * resource. - * @contents_len: An array into which the uncompressed data is written. - * It must be at least @len bytes long. +/* + * Reads all or part of a compressed WIM resource. * * Returns zero on success, nonzero on failure. */ -static int read_compressed_resource(FILE *fp, u64 resource_compressed_size, - u64 resource_uncompressed_size, - u64 resource_offset, int resource_ctype, - u64 len, u64 offset, u8 contents_ret[]) +static int +read_compressed_resource(int in_fd, + u64 resource_compressed_size, + u64 resource_uncompressed_size, + u64 resource_offset, + int resource_ctype, + u64 len, + u64 offset, + consume_data_callback_t cb, + void *ctx_or_buf) { + int ret; - DEBUG2("comp size = %"PRIu64", uncomp size = %"PRIu64", " - "res offset = %"PRIu64"", - resource_compressed_size, - resource_uncompressed_size, - resource_offset); - DEBUG2("resource_ctype = %s, len = %"PRIu64", offset = %"PRIu64"", - wimlib_get_compression_type_string(resource_ctype), len, offset); /* Trivial case */ 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) - decompress = lzx_decompress; + if (resource_ctype == WIMLIB_COMPRESSION_TYPE_LZX) + decompress = wimlib_lzx_decompress; else - decompress = xpress_decompress; + decompress = wimlib_xpress_decompress; /* The structure of a compressed resource consists of a table of chunk * offsets followed by the chunks themselves. Each chunk consists of @@ -87,10 +92,11 @@ static int read_compressed_resource(FILE *fp, u64 resource_compressed_size, * The chunk offsets are measured relative to the end of the chunk * table. The first chunk is omitted from the table in the WIM file * because its offset is implicitly given by the fact that it directly - * follows the chunk table and therefore must have an offset of 0. + * follows the chunk table and therefore must have an offset of 0. */ - /* Calculate how many chunks the resource conists of in its entirety. */ + /* Calculate how many chunks the resource consists of in its entirety. + * */ u64 num_chunks = (resource_uncompressed_size + WIM_CHUNK_SIZE - 1) / WIM_CHUNK_SIZE; /* As mentioned, the first chunk has no entry in the chunk table. */ @@ -117,9 +123,31 @@ static int read_compressed_resource(FILE *fp, u64 resource_compressed_size, if (end_chunk != num_chunks - 1) num_needed_chunks++; - /* Declare the chunk table. It will only contain offsets for the chunks - * that are actually needed for this read. */ - u64 chunk_offsets[num_needed_chunks]; + /* According to M$'s documentation, if the uncompressed size of + * the file is greater than 4 GB, the chunk entries are 8-byte + * integers. Otherwise, they are 4-byte integers. */ + u64 chunk_entry_size = (resource_uncompressed_size > + (u64)1 << 32) ? 8 : 4; + + /* Size of the full chunk table in the WIM file. */ + u64 chunk_table_size = chunk_entry_size * num_chunk_entries; + + /* Allocate the chunk table. It will only contain offsets for the + * chunks that are actually needed for this read. */ + u64 *chunk_offsets; + bool chunk_offsets_malloced; + if (num_needed_chunks < 1024) { + chunk_offsets = alloca(num_needed_chunks * sizeof(u64)); + chunk_offsets_malloced = false; + } else { + chunk_offsets = malloc(num_needed_chunks * sizeof(u64)); + if (!chunk_offsets) { + ERROR("Failed to allocate chunk table " + "with %"PRIu64" entries", num_needed_chunks); + return WIMLIB_ERR_NOMEM; + } + chunk_offsets_malloced = true; + } /* Set the implicit offset of the first chunk if it is included in the * needed chunks. @@ -132,14 +160,6 @@ static int read_compressed_resource(FILE *fp, u64 resource_compressed_size, if (start_chunk == 0) chunk_offsets[0] = 0; - /* According to M$'s documentation, if the uncompressed size of - * the file is greater than 4 GB, the chunk entries are 8-byte - * integers. Otherwise, they are 4-byte integers. */ - u64 chunk_entry_size = (resource_uncompressed_size >= (u64)1 << 32) ? - 8 : 4; - - /* Size of the full chunk table in the WIM file. */ - u64 chunk_table_size = chunk_entry_size * num_chunk_entries; /* Read the needed chunk offsets from the table in the WIM file. */ @@ -149,26 +169,41 @@ static int read_compressed_resource(FILE *fp, u64 resource_compressed_size, /* Number of entries we need to actually read from the chunk * table (excludes the implicit first chunk). */ - u64 num_needed_chunk_entries = (start_chunk == 0) ? + u64 num_needed_chunk_entries = (start_chunk == 0) ? num_needed_chunks - 1 : num_needed_chunks; /* Skip over unneeded chunk table entries. */ - u64 file_offset_of_needed_chunk_entries = resource_offset + + u64 file_offset_of_needed_chunk_entries = resource_offset + start_table_idx * chunk_entry_size; - if (fseeko(fp, file_offset_of_needed_chunk_entries, SEEK_SET) != 0) { - ERROR_WITH_ERRNO("Failed to seek to byte %"PRIu64" to read " - "chunk table of compressed resource", - file_offset_of_needed_chunk_entries); - return WIMLIB_ERR_READ; - } + + /* Allocate a buffer into which to read the raw chunk entries. */ + void *chunk_tab_buf; + bool chunk_tab_buf_malloced = false; /* Number of bytes we need to read from the chunk table. */ size_t size = num_needed_chunk_entries * chunk_entry_size; + if ((u64)size != num_needed_chunk_entries * chunk_entry_size) { + ERROR("Compressed read request too large to fit into memory!"); + ret = WIMLIB_ERR_NOMEM; + goto out; + } - u8 chunk_tab_buf[size]; + if (size < 4096) { + chunk_tab_buf = alloca(size); + } else { + chunk_tab_buf = malloc(size); + if (!chunk_tab_buf) { + ERROR("Failed to allocate chunk table buffer of " + "size %zu bytes", size); + ret = WIMLIB_ERR_NOMEM; + goto out; + } + chunk_tab_buf_malloced = true; + } - if (fread(chunk_tab_buf, 1, size, fp) != size) - goto err; + if (full_pread(in_fd, chunk_tab_buf, size, + file_offset_of_needed_chunk_entries) != size) + goto read_error; /* Now fill in chunk_offsets from the entries we have read in * chunk_tab_buf. */ @@ -178,30 +213,28 @@ static int read_compressed_resource(FILE *fp, u64 resource_compressed_size, chunk_tab_p++; if (chunk_entry_size == 4) { - u32 *entries = (u32*)chunk_tab_buf; + le32 *entries = (le32*)chunk_tab_buf; while (num_needed_chunk_entries--) - *chunk_tab_p++ = to_le32(*entries++); + *chunk_tab_p++ = le32_to_cpu(*entries++); } else { - u64 *entries = (u64*)chunk_tab_buf; + le64 *entries = (le64*)chunk_tab_buf; while (num_needed_chunk_entries--) - *chunk_tab_p++ = to_le64(*entries++); + *chunk_tab_p++ = le64_to_cpu(*entries++); } - /* Done with the chunk table now. We must now seek to the first chunk - * that is needed for the read. */ + /* Done reading the chunk table now. Now calculate the file offset for + * the first byte of compressed data we need to read. */ - u64 file_offset_of_first_needed_chunk = resource_offset + - chunk_table_size + chunk_offsets[0]; - if (fseeko(fp, file_offset_of_first_needed_chunk, SEEK_SET) != 0) { - ERROR_WITH_ERRNO("Failed to seek to byte %"PRIu64" to read " - "first chunk of compressed resource", - file_offset_of_first_needed_chunk); - return WIMLIB_ERR_READ; - } + u64 cur_read_offset = resource_offset + chunk_table_size + chunk_offsets[0]; /* Pointer to current position in the output buffer for uncompressed - * data. */ - u8 *out_p = (u8*)contents_ret; + * data. Alternatively, if using a callback function, we repeatedly + * fill a temporary buffer to feed data into the callback function. */ + u8 *out_p; + if (cb) + out_p = alloca(WIM_CHUNK_SIZE); + else + out_p = ctx_or_buf; /* Buffer for compressed data. While most compressed chunks will have a * size much less than WIM_CHUNK_SIZE, WIM_CHUNK_SIZE - 1 is the maximum @@ -209,24 +242,21 @@ static int read_compressed_resource(FILE *fp, u64 resource_compressed_size, * happen to compress to more than the uncompressed size (i.e. a * sequence of random bytes) are always stored uncompressed. But this seems * to be the case in M$'s WIM files, even though it is undocumented. */ - u8 compressed_buf[WIM_CHUNK_SIZE - 1]; - + void *compressed_buf = alloca(WIM_CHUNK_SIZE - 1); /* Decompress all the chunks. */ for (u64 i = start_chunk; i <= end_chunk; i++) { - DEBUG2("Chunk %"PRIu64" (start %"PRIu64", end %"PRIu64").", - i, start_chunk, end_chunk); - /* 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 * of compressed data for the chunk is given by the * difference of offsets in the chunk offset table. */ - compressed_chunk_size = chunk_offsets[i + 1 - start_chunk] - + compressed_chunk_size = chunk_offsets[i + 1 - start_chunk] - chunk_offsets[i - start_chunk]; uncompressed_chunk_size = WIM_CHUNK_SIZE; } else { @@ -234,15 +264,15 @@ static int read_compressed_resource(FILE *fp, u64 resource_compressed_size, * bytes in the file resource, and the last uncompressed * chunk has size equal to however many bytes are left- * that is, the remainder of the uncompressed size when - * divided by WIM_CHUNK_SIZE. + * divided by WIM_CHUNK_SIZE. * * Note that the resource_compressed_size includes the * chunk table, so the size of it must be subtracted. */ - compressed_chunk_size = resource_compressed_size - + compressed_chunk_size = resource_compressed_size - chunk_table_size - chunk_offsets[i - start_chunk]; - uncompressed_chunk_size = resource_uncompressed_size % + uncompressed_chunk_size = resource_uncompressed_size % WIM_CHUNK_SIZE; /* If the remainder is 0, the last chunk actually @@ -251,11 +281,6 @@ static int read_compressed_resource(FILE *fp, u64 resource_compressed_size, uncompressed_chunk_size = WIM_CHUNK_SIZE; } - DEBUG2("compressed_chunk_size = %u, " - "uncompressed_chunk_size = %u", - compressed_chunk_size, uncompressed_chunk_size); - - /* Figure out how much of this chunk we actually need to read */ u64 start_offset; if (i == start_chunk) @@ -268,965 +293,487 @@ static int read_compressed_resource(FILE *fp, u64 resource_compressed_size, else end_offset = WIM_CHUNK_SIZE - 1; - u64 partial_chunk_size = end_offset + 1 - start_offset; - 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); + unsigned partial_chunk_size = end_offset + 1 - start_offset; + bool is_partial_chunk = (partial_chunk_size != uncompressed_chunk_size); /* This is undocumented, but chunks can be uncompressed. This * appears to always be the case when the compressed chunk size * is equal to the uncompressed chunk size. */ if (compressed_chunk_size == uncompressed_chunk_size) { - /* Probably an uncompressed chunk */ - - if (start_offset != 0) { - if (fseeko(fp, start_offset, SEEK_CUR) != 0) { - ERROR_WITH_ERRNO("Uncompressed partial " - "chunk fseek() error"); - return WIMLIB_ERR_READ; - } + /* Uncompressed chunk */ + if (full_pread(in_fd, + cb ? out_p + start_offset : out_p, + partial_chunk_size, + cur_read_offset + start_offset) != partial_chunk_size) + { + goto read_error; } - if (fread(out_p, 1, partial_chunk_size, fp) != - partial_chunk_size) - goto err; } else { /* Compressed chunk */ - int ret; /* Read the compressed data into compressed_buf. */ - if (fread(compressed_buf, 1, compressed_chunk_size, - fp) != compressed_chunk_size) - goto err; + if (full_pread(in_fd, + compressed_buf, + compressed_chunk_size, + cur_read_offset) != compressed_chunk_size) + { + goto read_error; + } - /* For partial chunks we must buffer the uncompressed - * data because we don't need all of it. */ - if (is_partial_chunk) { + /* For partial chunks and when writing directly to a + * buffer, we must buffer the uncompressed data because + * we don't need all of it. */ + if (is_partial_chunk && !cb) { u8 uncompressed_buf[uncompressed_chunk_size]; ret = decompress(compressed_buf, - compressed_chunk_size, - uncompressed_buf, - uncompressed_chunk_size); - if (ret != 0) - return WIMLIB_ERR_DECOMPRESSION; + compressed_chunk_size, + uncompressed_buf, + uncompressed_chunk_size); + if (ret) { + ret = WIMLIB_ERR_DECOMPRESSION; + goto out; + } memcpy(out_p, uncompressed_buf + start_offset, - partial_chunk_size); + partial_chunk_size); } else { ret = decompress(compressed_buf, - compressed_chunk_size, - out_p, - uncompressed_chunk_size); - if (ret != 0) - return WIMLIB_ERR_DECOMPRESSION; + compressed_chunk_size, + out_p, + uncompressed_chunk_size); + if (ret) { + ret = WIMLIB_ERR_DECOMPRESSION; + goto out; + } } } - - /* Advance the pointer into the uncompressed output data by the - * number of uncompressed bytes that were written. */ - out_p += partial_chunk_size; + if (cb) { + /* Feed the data to the callback function */ + ret = cb(out_p + start_offset, + partial_chunk_size, ctx_or_buf); + if (ret) + goto out; + } else { + /* No callback function provided; we are writing + * directly to a buffer. Advance the pointer into this + * buffer by the number of uncompressed bytes that were + * written. */ + out_p += partial_chunk_size; + } + cur_read_offset += compressed_chunk_size; } - return 0; + ret = 0; +out: + if (chunk_offsets_malloced) + FREE(chunk_offsets); + if (chunk_tab_buf_malloced) + FREE(chunk_tab_buf); + return ret; -err: - if (feof(fp)) - ERROR("Unexpected EOF in compressed file resource"); - else - ERROR_WITH_ERRNO("Error reading compressed file resource"); - return WIMLIB_ERR_READ; +read_error: + ERROR_WITH_ERRNO("Error reading compressed file resource"); + ret = WIMLIB_ERR_READ; + goto out; } -/* - * Reads uncompressed data from an open file stream. - */ -int read_uncompressed_resource(FILE *fp, u64 offset, u64 len, - u8 contents_ret[]) +/* Translates a WIM resource entry from the on-disk format to an in-memory + * format. */ +void +get_resource_entry(const struct resource_entry_disk *disk_entry, + struct resource_entry *entry) { - if (fseeko(fp, offset, SEEK_SET) != 0) { - ERROR("Failed to seek to byte %"PRIu64" of input file " - "to read uncompressed resource (len = %"PRIu64")", - offset, len); - return WIMLIB_ERR_READ; + /* Note: disk_entry may not be 8 byte aligned--- in that case, the + * offset and original_size members will be unaligned. (This should be + * okay since `struct resource_entry_disk' is declared as packed.) */ + + /* Read the size and flags into a bitfield portably... */ + entry->size = (((u64)disk_entry->size[0] << 0) | + ((u64)disk_entry->size[1] << 8) | + ((u64)disk_entry->size[2] << 16) | + ((u64)disk_entry->size[3] << 24) | + ((u64)disk_entry->size[4] << 32) | + ((u64)disk_entry->size[5] << 40) | + ((u64)disk_entry->size[6] << 48)); + entry->flags = disk_entry->flags; + entry->offset = le64_to_cpu(disk_entry->offset); + entry->original_size = le64_to_cpu(disk_entry->original_size); + + /* offset and original_size are truncated to 62 bits to avoid possible + * overflows, when converting to a signed 64-bit integer (off_t) or when + * adding size or original_size. This is okay since no one would ever + * actually have a WIM bigger than 4611686018427387903 bytes... */ + if (entry->offset & 0xc000000000000000ULL) { + WARNING("Truncating offset in resource entry"); + entry->offset &= 0x3fffffffffffffffULL; } - if (fread(contents_ret, 1, len, fp) != len) { - if (feof(fp)) { - ERROR("Unexpected EOF in uncompressed file resource"); - } else { - ERROR("Failed to read %"PRIu64" bytes from " - "uncompressed resource at offset %"PRIu64, - len, offset); - } - return WIMLIB_ERR_READ; + if (entry->original_size & 0xc000000000000000ULL) { + WARNING("Truncating original_size in resource entry"); + entry->original_size &= 0x3fffffffffffffffULL; } - return 0; } - -/* - * Reads a WIM resource. - * - * @fp: The FILE* for the WIM file. - * @resource_size: The compressed size of the resource. - * @resource_original_size: The uncompressed size of the resource. - * @resource_offset: The offset of the resource in the stream @fp. - * @resource_ctype: The compression type of the resource. - * (WIM_COMPRESSION_TYPE_*) - * @len: How many bytes of the resource should be read. - * @offset: The offset within the resource at which the read - * will occur. - * - * To read the whole file resource, specify offset = - * 0 and len = resource_original_size, or call - * read_full_resource(). - * - * @contents_ret: An array, that must have length at least @len, - * into which the uncompressed contents of - * the file resource starting at @offset and - * continuing for @len bytes will be written. - * - * @return: Zero on success, nonzero on failure. Failure may be due to - * being unable to read the data from the WIM file at the - * specified length and offset, or it may be due to the - * compressed data (if the data is compressed) being - * invalid. - */ -int read_resource(FILE *fp, u64 resource_size, u64 resource_original_size, - u64 resource_offset, int resource_ctype, u64 len, - u64 offset, void *contents_ret) +/* Translates a WIM resource entry from an in-memory format into the on-disk + * format. */ +void +put_resource_entry(const struct resource_entry *entry, + struct resource_entry_disk *disk_entry) { - if (resource_ctype == WIM_COMPRESSION_TYPE_NONE) { - if (resource_size != resource_original_size) { - ERROR("Resource with original size %"PRIu64" bytes is " - "marked as uncompressed, but its actual size is " - "%"PRIu64" bytes", - resource_original_size, resource_size); - return WIMLIB_ERR_INVALID_RESOURCE_SIZE; - } - return read_uncompressed_resource(fp, - resource_offset + offset, - len, contents_ret); - } else { - return read_compressed_resource(fp, resource_size, - resource_original_size, resource_offset, - resource_ctype, len, offset, contents_ret); - } + /* Note: disk_entry may not be 8 byte aligned--- in that case, the + * offset and original_size members will be unaligned. (This should be + * okay since `struct resource_entry_disk' is declared as packed.) */ + u64 size = entry->size; + + disk_entry->size[0] = size >> 0; + disk_entry->size[1] = size >> 8; + disk_entry->size[2] = size >> 16; + disk_entry->size[3] = size >> 24; + disk_entry->size[4] = size >> 32; + disk_entry->size[5] = size >> 40; + disk_entry->size[6] = size >> 48; + disk_entry->flags = entry->flags; + disk_entry->offset = cpu_to_le64(entry->offset); + disk_entry->original_size = cpu_to_le64(entry->original_size); } - -/* - * Extracts the first @size bytes file resource specified by @entry to the open - * file @fd. Returns nonzero on error. - * - * XXX - * This function is somewhat redundant with uncompress_resource(). The - * main difference is that this function writes to a file descriptor using - * low-level calls to write() rather than to a FILE* with fwrite(); also this - * function allows only up to @size bytes to be extracted. - */ -int extract_resource_to_fd(WIMStruct *w, const struct resource_entry *entry, - int fd, u64 size) +static int +read_partial_wim_resource(const struct wim_lookup_table_entry *lte, + u64 size, + consume_data_callback_t cb, + void *ctx_or_buf, + int flags, + u64 offset) { - u64 num_chunks; - u64 n; - u8 buf[min(size, WIM_CHUNK_SIZE)]; - int res_ctype; - u64 offset; - u64 i; + WIMStruct *wim; + int in_fd; int ret; - errno = 0; - - num_chunks = (size + WIM_CHUNK_SIZE - 1) / WIM_CHUNK_SIZE; - n = WIM_CHUNK_SIZE; - res_ctype = wim_resource_compression_type(w, entry); - offset = 0; - for (i = 0; i < num_chunks; i++) { - if (i == num_chunks - 1) { - n = size % WIM_CHUNK_SIZE; - if (n == 0) { - n = WIM_CHUNK_SIZE; - } - } + wimlib_assert(lte->resource_location == RESOURCE_IN_WIM); - ret = read_resource(w->fp, entry->size, entry->original_size, - entry->offset, res_ctype, n, offset, buf); - if (ret != 0) - return ret; + wim = lte->wim; + in_fd = wim->in_fd; - if (full_write(fd, buf, n) != n) - return WIMLIB_ERR_WRITE; - offset += n; + if (lte->resource_entry.flags & WIM_RESHDR_FLAG_COMPRESSED && + !(flags & WIMLIB_RESOURCE_FLAG_RAW)) + { + ret = read_compressed_resource(in_fd, + lte->resource_entry.size, + lte->resource_entry.original_size, + lte->resource_entry.offset, + wimlib_get_compression_type(wim), + size, + offset, + cb, + ctx_or_buf); + } else { + offset += lte->resource_entry.offset; + if (cb) { + /* Send data to callback function */ + u8 buf[min(WIM_CHUNK_SIZE, size)]; + while (size) { + size_t bytes_to_read = min(WIM_CHUNK_SIZE, size); + size_t bytes_read = full_pread(in_fd, buf, + bytes_to_read, offset); + if (bytes_read != bytes_to_read) + goto read_error; + ret = cb(buf, bytes_read, ctx_or_buf); + if (ret) + goto out; + size -= bytes_read; + offset += bytes_read; + } + } else { + /* Send data directly to a buffer */ + if (full_pread(in_fd, ctx_or_buf, size, offset) != size) + goto read_error; + } + ret = 0; } - return ret; -} - -/* - * Copies the file resource specified by the lookup table entry @lte from the - * input WIM, pointed to by the fp field of the WIMStruct, to the output WIM, - * pointed to by the out_fp field of the WIMStruct. - * - * 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). - */ -int copy_resource(struct lookup_table_entry *lte, void *w) -{ - if ((lte->resource_entry.flags & WIM_RESHDR_FLAG_METADATA) && - !((WIMStruct*)w)->write_metadata) { - return 0; + goto out; +read_error: + ERROR_WITH_ERRNO("Error reading data from WIM"); + ret = WIMLIB_ERR_READ; +out: + if (ret) { + if (errno == 0) + errno = EIO; } - - FILE *in_fp = ((WIMStruct*)w)->fp; - FILE *out_fp = ((WIMStruct*)w)->out_fp; - int ret; - u64 size = lte->resource_entry.size; - u64 offset = lte->resource_entry.offset; - off_t new_offset = ftello(out_fp); - - if (new_offset == -1) - return WIMLIB_ERR_WRITE; - - ret = copy_between_files(in_fp, offset, out_fp, size); - if (ret != 0) - return ret; - - memcpy(<e->output_resource_entry, <e->resource_entry, - sizeof(struct resource_entry)); - - lte->output_resource_entry.offset = new_offset; - lte->out_refcnt = lte->refcnt; - lte->part_number = ((WIMStruct*)w)->hdr.part_number; - return 0; + return ret; } -/* 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. */ -const u8 *get_resource_entry(const u8 *p, struct resource_entry *entry) -{ - u64 size; - u8 flags; - - p = get_u56(p, &size); - p = get_u8(p, &flags); - entry->size = size; - entry->flags = flags; - p = get_u64(p, &entry->offset); - p = get_u64(p, &entry->original_size); - return p; -} -/* Copies the struct resource_entry @entry to the memory pointed to by @p in the - * on-disk format. A pointer to the byte after the memory written at @p is - * returned. */ -u8 *put_resource_entry(u8 *p, const struct resource_entry *entry) +int +read_partial_wim_resource_into_buf(const struct wim_lookup_table_entry *lte, + size_t size, u64 offset, void *buf) { - p = put_u56(p, entry->size); - p = put_u8(p, entry->flags); - p = put_u64(p, entry->offset); - p = put_u64(p, entry->original_size); - return p; + return read_partial_wim_resource(lte, size, NULL, buf, 0, offset); } -/* Given the compression type for the WIM file as a whole as the flags field of - * a resource entry, returns the compression type for that resource entry. */ -int resource_compression_type(int wim_ctype, int reshdr_flags) +static int +read_wim_resource_prefix(const struct wim_lookup_table_entry *lte, + u64 size, + consume_data_callback_t cb, + void *ctx_or_buf, + int flags) { - if (wim_ctype != WIM_COMPRESSION_TYPE_NONE && - (reshdr_flags & WIM_RESHDR_FLAG_COMPRESSED)) - return wim_ctype; - else - return WIM_COMPRESSION_TYPE_NONE; + return read_partial_wim_resource(lte, size, cb, ctx_or_buf, flags, 0); } - -/* - * Copies bytes between two file streams. - * - * Copies @len bytes from @in_fp to @out_fp, at the current position in @out_fp, - * and at an offset of @in_offset in @in_fp. - */ -int copy_between_files(FILE *in_fp, off_t in_offset, FILE *out_fp, size_t len) +#ifndef __WIN32__ +static int +read_file_on_disk_prefix(const struct wim_lookup_table_entry *lte, + u64 size, + consume_data_callback_t cb, + void *ctx_or_buf, + int _ignored_flags) { - u8 buf[BUFFER_SIZE]; - size_t n; + const tchar *filename = lte->file_on_disk; + int ret; + int fd; + size_t bytes_read; - if (fseeko(in_fp, in_offset, SEEK_SET) != 0) { - ERROR_WITH_ERRNO("Failed to seek to byte %"PRIu64" of " - "input file", in_offset); - return WIMLIB_ERR_READ; + fd = open(filename, O_RDONLY); + if (fd < 0) { + ERROR_WITH_ERRNO("Can't open \"%"TS"\"", filename); + return WIMLIB_ERR_OPEN; } - /* To reduce memory usage and improve speed, read and write BUFFER_SIZE - * bytes at a time. */ - while (len != 0) { - n = min(len, BUFFER_SIZE); - if (fread(buf, 1, n, in_fp) != n) { - if (feof(in_fp)) { - ERROR("Unexpected EOF when copying data " - "between files"); - } else { - ERROR_WITH_ERRNO("Error copying data between " - "files"); - } - return WIMLIB_ERR_READ; - } - - if (fwrite(buf, 1, n, out_fp) != n) { - ERROR_WITH_ERRNO("Error copying data between files"); - return WIMLIB_ERR_WRITE; - } - len -= n; - } - return 0; -} - - -/* - * Uncompresses a WIM file resource and writes it uncompressed to a file stream. - * - * @in_fp: The file stream that contains the file resource. - * @size: The size of the resource in the input file. - * @original_size: The original (uncompressed) size of the resource. - * @offset: The offset of the start of the resource in @in. - * @input_ctype: The compression type of the resource in @in. - * @out_fp: The file stream to write the file resource to. - */ -static int uncompress_resource(FILE *in_fp, u64 size, u64 original_size, - off_t offset, int input_ctype, FILE *out_fp) -{ - int ret; - u8 buf[WIM_CHUNK_SIZE]; - /* Determine how many compressed chunks the file is divided into. */ - u64 num_chunks; - u64 i; - u64 uncompressed_offset; - u64 uncompressed_chunk_size; - - num_chunks = (original_size + WIM_CHUNK_SIZE - 1) / WIM_CHUNK_SIZE; - - for (i = 0; i < num_chunks; i++) { - - uncompressed_offset = i * WIM_CHUNK_SIZE; - uncompressed_chunk_size = min(WIM_CHUNK_SIZE, original_size - - uncompressed_offset); - - ret = read_resource(in_fp, size, original_size, offset, - input_ctype, uncompressed_chunk_size, - uncompressed_offset, buf); - if (ret != 0) - return ret; - - if (fwrite(buf, 1, uncompressed_chunk_size, out_fp) != - uncompressed_chunk_size) - { - ERROR_WITH_ERRNO("Failed to write file resource"); - return WIMLIB_ERR_WRITE; + if (cb) { + /* Send data to callback function */ + u8 buf[min(WIM_CHUNK_SIZE, size)]; + size_t bytes_to_read; + while (size) { + bytes_to_read = min(WIM_CHUNK_SIZE, size); + bytes_read = full_read(fd, buf, bytes_to_read); + if (bytes_read != bytes_to_read) + goto read_error; + ret = cb(buf, bytes_read, ctx_or_buf); + if (ret) + goto out_close; + size -= bytes_read; } + } else { + /* Send data directly to a buffer */ + bytes_read = full_read(fd, ctx_or_buf, size); + if (bytes_read != size) + goto read_error; } - return 0; + ret = 0; + goto out_close; +read_error: + ERROR_WITH_ERRNO("Error reading \"%"TS"\"", filename); + ret = WIMLIB_ERR_READ; +out_close: + close(fd); + return ret; } +#endif /* !__WIN32__ */ -/* - * Transfers a file resource between two files, writing it compressed. The file - * resource in the input file may be either compressed or uncompressed. - * Alternatively, the input resource may be in-memory, but it must be - * uncompressed. - * - * @in_fp: The file stream that contains the file resource. Ignored - * if uncompressed_resource != NULL. - * @uncompressed_resource: If this pointer is not NULL, it points to an - * array of @original_size bytes that are - * the uncompressed input resource. - * @size: The size of the resource in the input file. - * @original_size: The original (uncompressed) size of the resource. - * @offset: The offset of the start of the resource in @in. Ignored - * if uncompressed_resource != NULL. - * @input_ctype: The compression type of the resource in @in. Ignored if - * uncompressed_resource != NULL. - * @out_fp: The file stream to write the file resource to. - * @output_type: The compression type to use when writing the resource to - * @out. - * @new_size_ret: A location into which the new compressed size of the file - * resource in returned. - */ -static int recompress_resource(FILE *in_fp, const u8 *uncompressed_resource, - u64 size, u64 original_size, - off_t offset, int input_ctype, FILE *out_fp, - int output_ctype, u64 *new_size_ret) +static int +read_buffer_prefix(const struct wim_lookup_table_entry *lte, + u64 size, consume_data_callback_t cb, + void *ctx_or_buf, int _ignored_flags) { + const void *inbuf = lte->attached_buffer; int ret; - int (*compress)(const void *, uint, void *, uint *); - if (output_ctype == WIM_COMPRESSION_TYPE_LZX) - compress = lzx_compress; - else - compress = xpress_compress; - - u8 uncompressed_buf[WIM_CHUNK_SIZE]; - u8 compressed_buf[WIM_CHUNK_SIZE - 1]; - - /* Determine how many compressed chunks the file needs to be divided - * into. */ - u64 num_chunks = (original_size + WIM_CHUNK_SIZE - 1) / WIM_CHUNK_SIZE; - - u64 num_chunk_entries = num_chunks - 1; - - /* Size of the chunk entries--- 8 bytes for files over 4GB, otherwise 4 - * bytes */ - uint chunk_entry_size = (original_size >= (u64)1 << 32) ? 8 : 4; - - /* Array in which to construct the chunk offset table. */ - u64 chunk_offsets[num_chunk_entries]; - /* Offset of the start of the chunk table in the output file. */ - off_t chunk_tab_offset = ftello(out_fp); - - if (chunk_tab_offset == -1) { - ERROR_WITH_ERRNO("Failed to get offset of output file"); - return WIMLIB_ERR_WRITE; - } - - /* Total size of the chunk table (as written to the file) */ - u64 chunk_tab_size = chunk_entry_size * num_chunk_entries; - - /* Reserve space for the chunk table. */ - if (fwrite(chunk_offsets, 1, chunk_tab_size, out_fp) != - chunk_tab_size) - { - ERROR_WITH_ERRNO("Failed to write chunk offset table"); - return WIMLIB_ERR_WRITE; - } - - /* Read each chunk of the file, compress it, write it to the output - * file, and update th chunk offset table. */ - u64 cur_chunk_offset = 0; - for (u64 i = 0; i < num_chunks; i++) { - - u64 uncompressed_offset = i * WIM_CHUNK_SIZE; - u64 uncompressed_chunk_size = min(WIM_CHUNK_SIZE, - original_size - uncompressed_offset); - - const u8 *uncompressed_p; - if (uncompressed_resource != NULL) { - uncompressed_p = uncompressed_resource + - uncompressed_offset; - - } else { - /* Read chunk i of the file into uncompressed_buf. */ - ret = read_resource(in_fp, size, original_size, offset, - input_ctype, - uncompressed_chunk_size, - uncompressed_offset, - uncompressed_buf); - if (ret != 0) + if (cb) { + while (size) { + size_t chunk_size = min(WIM_CHUNK_SIZE, size); + ret = cb(inbuf, chunk_size, ctx_or_buf); + if (ret) return ret; - uncompressed_p = uncompressed_buf; - } - - if (i != 0) - chunk_offsets[i - 1] = cur_chunk_offset; - - uint compressed_len; - - ret = compress(uncompressed_p, uncompressed_chunk_size, - compressed_buf, &compressed_len); - - /* if compress() returned nonzero, the compressed chunk would - * have been at least as large as the uncompressed chunk. In - * this situation, the WIM format requires that the uncompressed - * chunk be written instead. */ - const u8 *buf_to_write; - uint len_to_write; - if (ret == 0) { - buf_to_write = compressed_buf; - len_to_write = compressed_len; - } else { - buf_to_write = uncompressed_p; - len_to_write = uncompressed_chunk_size; + size -= chunk_size; + inbuf += chunk_size; } - - if (fwrite(buf_to_write, 1, len_to_write, out_fp) != - len_to_write) - { - ERROR_WITH_ERRNO("Failed to write compressed " - "file resource"); - return WIMLIB_ERR_WRITE; - } - cur_chunk_offset += len_to_write; - } - - /* The chunk offset after the last chunk, plus the size of the chunk - * table, gives the total compressed size of the resource. */ - *new_size_ret = cur_chunk_offset + chunk_tab_size; - - /* Now that all entries of the chunk table are determined, rewind the - * stream to where the chunk table was, and write it back out. */ - - if (fseeko(out_fp, chunk_tab_offset, SEEK_SET) != 0) { - ERROR_WITH_ERRNO("Failed to seek to beginning of chunk table"); - return WIMLIB_ERR_READ; - } - - if (chunk_entry_size == 8) { - array_to_le64(chunk_offsets, num_chunk_entries); } else { - for (u64 i = 0; i < num_chunk_entries; i++) - ((u32*)chunk_offsets)[i] = to_le32(chunk_offsets[i]); + memcpy(ctx_or_buf, inbuf, size); } - if (fwrite(chunk_offsets, 1, chunk_tab_size, out_fp) != chunk_tab_size) - { - ERROR_WITH_ERRNO("Failed to write chunk table"); - return WIMLIB_ERR_WRITE; - } - - if (fseeko(out_fp, 0, SEEK_END) != 0) { - ERROR_WITH_ERRNO("Failed to seek to end of output file"); - return WIMLIB_ERR_WRITE; - } - return 0; } -int write_resource_from_memory(const u8 resource[], int out_ctype, - u64 resource_original_size, FILE *out_fp, - u64 *resource_size_ret) -{ - if (out_ctype == WIM_COMPRESSION_TYPE_NONE) { - if (fwrite(resource, 1, resource_original_size, out_fp) != - resource_original_size) - { - ERROR_WITH_ERRNO("Failed to write resource of length " - "%"PRIu64, resource_original_size); - return WIMLIB_ERR_WRITE; - } - *resource_size_ret = resource_original_size; - return 0; - } else { - return recompress_resource(NULL, resource, - resource_original_size, - resource_original_size, 0, 0, out_fp, - out_ctype, resource_size_ret); - } -} - +typedef int (*read_resource_prefix_handler_t)(const struct wim_lookup_table_entry *lte, + u64 size, + consume_data_callback_t cb, + void *ctx_or_buf, + int flags); -/* - * Transfers a file resource from a FILE* opened for reading to a FILE* opened - * for writing, possibly changing the compression type. +/* + * Read the first @size bytes from a generic "resource", which may be located in + * the WIM (compressed or uncompressed), in an external file, or directly in an + * in-memory buffer. + * + * Feed the data either to a callback function (cb != NULL, passing it + * ctx_or_buf), or write it directly into a buffer (cb == NULL, ctx_or_buf + * specifies the buffer, which must have room for @size bytes). * - * @in_fp: The FILE* that contains the file resource. - * @size: The (compressed) size of the file resource. - * @original_size: The uncompressed size of the file resource. - * @offset: The offset of the file resource in the input file. - * @input_ctype: The compression type of the file resource in the input - * file. - * @out_fp: The FILE* for the output file. The file resource is - * written at the current position of @out. - * @output_ctype: The compression type to which the file resource will be - * converted. - * @output_res_entry: A pointer to a resource entry that, upon successful - * return of this function, will have the size, - * original size, offset, and flags fields filled - * in for the file resource written to the output - * file. + * When using a callback function, it is called with chunks up to 32768 bytes in + * size until the resource is exhausted. + * + * If the resource is located in a WIM file, @flags can be: + * * WIMLIB_RESOURCE_FLAG_RAW if the raw compressed data is to be supplied + * instead of the uncompressed data. + * Otherwise, the @flags are ignored. */ -static int transfer_file_resource(FILE *in_fp, u64 size, u64 original_size, - off_t offset, int input_ctype, FILE *out_fp, - int output_ctype, - struct resource_entry *output_res_entry) +int +read_resource_prefix(const struct wim_lookup_table_entry *lte, + u64 size, consume_data_callback_t cb, void *ctx_or_buf, + int flags) { - int ret; - - /* Handle zero-length files */ - if (original_size == 0) { - memset(output_res_entry, 0, sizeof(*output_res_entry)); - return 0; - } + static const read_resource_prefix_handler_t handlers[] = { + [RESOURCE_IN_WIM] = read_wim_resource_prefix, + #ifndef __WIN32__ + [RESOURCE_IN_FILE_ON_DISK] = read_file_on_disk_prefix, + #endif + [RESOURCE_IN_ATTACHED_BUFFER] = read_buffer_prefix, + #ifdef WITH_FUSE + [RESOURCE_IN_STAGING_FILE] = read_file_on_disk_prefix, + #endif + #ifdef WITH_NTFS_3G + [RESOURCE_IN_NTFS_VOLUME] = read_ntfs_file_prefix, + #endif + #ifdef __WIN32__ + [RESOURCE_WIN32] = read_win32_file_prefix, + [RESOURCE_WIN32_ENCRYPTED] = read_win32_encrypted_file_prefix, + #endif + }; + wimlib_assert(lte->resource_location < ARRAY_LEN(handlers) + && handlers[lte->resource_location] != NULL); + return handlers[lte->resource_location](lte, size, cb, ctx_or_buf, flags); +} - /* Get current offset in the output file. */ - off_t out_offset = ftello(out_fp); - if (out_offset == -1) { - ERROR_WITH_ERRNO("Failed to get output position"); - return WIMLIB_ERR_WRITE; - } - output_res_entry->offset = (u64)out_offset; +int +read_full_resource_into_buf(const struct wim_lookup_table_entry *lte, + void *buf) +{ + return read_resource_prefix(lte, wim_resource_size(lte), NULL, buf, 0); +} - if (output_ctype == input_ctype) { - /* The same compression types; simply copy the resource. */ +struct extract_ctx { + SHA_CTX sha_ctx; + consume_data_callback_t extract_chunk; + void *extract_chunk_arg; +}; - ret = copy_between_files(in_fp, offset, out_fp, size); - if (ret != 0) - return ret; - output_res_entry->size = size; - } else { - /* Different compression types. */ - - if (output_ctype == WIM_COMPRESSION_TYPE_NONE) { - /* Uncompress a compressed file resource */ - ret = uncompress_resource(in_fp, size, - original_size, offset, - input_ctype, out_fp); - if (ret != 0) - return ret; - output_res_entry->size = original_size; - } else { - u64 new_size; - /* Compress an uncompressed file resource, or compress a - * compressed file resource using a different - * compression type */ - ret = recompress_resource(in_fp, NULL, size, - original_size, - offset, input_ctype, out_fp, - output_ctype, &new_size); - if (ret != 0) - return ret; - output_res_entry->size = new_size; - } - - } +static int +extract_chunk_sha1_wrapper(const void *chunk, size_t chunk_size, + void *_ctx) +{ + struct extract_ctx *ctx = _ctx; - output_res_entry->original_size = original_size; - if (output_ctype == WIM_COMPRESSION_TYPE_NONE) - output_res_entry->flags = 0; - else - output_res_entry->flags = WIM_RESHDR_FLAG_COMPRESSED; - return 0; + sha1_update(&ctx->sha_ctx, chunk, chunk_size); + return ctx->extract_chunk(chunk, chunk_size, ctx->extract_chunk_arg); } -/* - * 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 - * `lookup_table_entry' member specifies the lookup table entry for - * the metadata resource. The rest of the image metadata entry - * will be filled in by this function. +/* 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. * - * @return: Zero on success, nonzero on failure. - */ -int read_metadata_resource(FILE *fp, int wim_ctype, struct image_metadata *imd) + * @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, + consume_data_callback_t extract_chunk, + void *extract_chunk_arg) { - u8 *buf; - int ctype; - u32 dentry_offset; int ret; - const struct resource_entry *res_entry; - struct dentry *dentry; - struct wim_security_data *sd; - struct link_group_table *lgt; - - res_entry = &imd->metadata_lte->resource_entry; - - DEBUG("Reading metadata resource: length = %"PRIu64", " - "offset = %"PRIu64"", - res_entry->original_size, res_entry->offset); - - if (res_entry->original_size < 8) { - ERROR("Expected at least 8 bytes for the metadata resource"); - return WIMLIB_ERR_INVALID_RESOURCE_SIZE; - } - - /* Allocate memory for the uncompressed metadata resource. */ - buf = MALLOC(res_entry->original_size); - - if (!buf) { - ERROR("Failed to allocate %"PRIu64" bytes for uncompressed " - "metadata resource", res_entry->original_size); - return WIMLIB_ERR_NOMEM; - } - - /* Determine the compression type of the metadata resource. */ - ctype = resource_compression_type(wim_ctype, res_entry->flags); - - /* Read the metadata resource into memory. (It may be compressed.) */ - ret = read_full_resource(fp, res_entry->size, - res_entry->original_size, res_entry->offset, - ctype, buf); - if (ret != 0) - goto out_free_buf; - - DEBUG("Finished reading metadata resource into memory."); - - /* The root directory entry starts after security data, on an 8-byte - * aligned address. - * - * The security data starts with a 4-byte integer giving its total - * length. */ - - /* Read the security data into a wim_security_data structure. */ - ret = read_security_data(buf, res_entry->original_size, &sd); - if (ret != 0) - goto out_free_buf; - - 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; + if (size == wim_resource_size(lte)) { + /* Do SHA1 */ + struct extract_ctx ctx; + ctx.extract_chunk = extract_chunk; + ctx.extract_chunk_arg = extract_chunk_arg; + sha1_init(&ctx.sha_ctx); + ret = read_resource_prefix(lte, size, + extract_chunk_sha1_wrapper, + &ctx, 0); + if (ret == 0) { + u8 hash[SHA1_HASH_SIZE]; + sha1_final(hash, &ctx.sha_ctx); + if (!hashes_equal(hash, lte->hash)) { + #ifdef ENABLE_ERROR_MESSAGES + ERROR("Invalid SHA1 message digest " + "on the following WIM resource:"); + print_lookup_table_entry(lte, stderr); + if (lte->resource_location == RESOURCE_IN_WIM) + ERROR("The WIM file appears to be corrupt!"); + #endif + ret = WIMLIB_ERR_INVALID_RESOURCE_HASH; + } + } + } else { + /* Don't do SHA1 */ + ret = read_resource_prefix(lte, size, extract_chunk, + extract_chunk_arg, 0); } - - get_u32(buf, &dentry_offset); - if (dentry_offset == 0) - dentry_offset = 8; - dentry_offset = (dentry_offset + 7) & ~7; - - ret = read_dentry(buf, res_entry->original_size, dentry_offset, dentry); - /* This is the root dentry, so set its pointers correctly. */ - dentry->parent = dentry; - dentry->next = dentry; - dentry->prev = dentry; - if (ret != 0) - goto out_free_dentry_tree; - - /* Now read the entire directory entry tree. */ - ret = read_dentry_tree(buf, res_entry->original_size, dentry); - if (ret != 0) - goto out_free_dentry_tree; - - /* Calculate the full paths in the dentry tree. */ - ret = for_dentry_in_tree(dentry, calculate_dentry_full_path, NULL); - if (ret != 0) - goto out_free_dentry_tree; - - lgt = new_link_group_table(9001); - if (!lgt) - goto out_free_dentry_tree; - ret = for_dentry_in_tree(dentry, link_group_table_insert, lgt); - if (ret != 0) - goto out_free_lgt; - - imd->lgt = lgt; - imd->security_data = sd; - imd->root_dentry = dentry; - goto out_free_buf; -out_free_lgt: - free_link_group_table(sgt); -out_free_dentry_tree: - free_dentry_tree(dentry, NULL, false); -out_free_security_data: - free_security_data(sd); -out_free_buf: - FREE(buf); return ret; } -/* Write the metadata resource for the current image. */ -int write_metadata_resource(WIMStruct *w) +static int +extract_wim_chunk_to_fd(const void *buf, size_t len, void *_fd_p) { - FILE *out; - u8 *buf; - u8 *p; - int ret; - u64 subdir_offset; - struct dentry *root; - struct lookup_table_entry *lte; - struct resource_entry *res_entry; - off_t metadata_offset; - u64 metadata_original_size; - u64 metadata_compressed_size; - int metadata_ctype; - u8 hash[WIM_HASH_SIZE]; - - DEBUG("Writing metadata resource for image %d", w->current_image); - - out = w->out_fp; - root = wim_root_dentry(w); - metadata_ctype = wimlib_get_compression_type(w); - metadata_offset = ftello(out); - if (metadata_offset == -1) + int fd = *(int*)_fd_p; + ssize_t ret = full_write(fd, buf, len); + if (ret < len) { + ERROR_WITH_ERRNO("Error writing to file descriptor"); return WIMLIB_ERR_WRITE; - - struct wim_security_data *sd = wim_security_data(w); - if (sd) - subdir_offset = sd->total_length + root->length + 8; - else - subdir_offset = 8 + root->length + 8; - calculate_subdir_offsets(root, &subdir_offset); - metadata_original_size = subdir_offset; - buf = MALLOC(metadata_original_size); - if (!buf) { - ERROR("Failed to allocate %"PRIu64" bytes for " - "metadata resource", metadata_original_size); - return WIMLIB_ERR_NOMEM; - } - - p = write_security_data(sd, buf); - - DEBUG("Writing dentry tree."); - p = write_dentry_tree(root, p); - - /* Like file resources, the lookup table entry for a metadata resource - * uses for the hash code a SHA1 message digest of its uncompressed - * contents. */ - sha1_buffer(buf, metadata_original_size, hash); - - ret = write_resource_from_memory(buf, - metadata_ctype, - metadata_original_size, - out, - &metadata_compressed_size); - FREE(buf); - if (ret != 0) - return ret; - - /* Update the lookup table entry, including the hash and output resource - * entry fields, for this image's metadata resource. */ - lte = wim_metadata_lookup_table_entry(w); - res_entry = <e->output_resource_entry; - lte->out_refcnt++; - if (memcmp(hash, lte->hash, WIM_HASH_SIZE) != 0) { - lookup_table_unlink(w->lookup_table, lte); - memcpy(lte->hash, hash, WIM_HASH_SIZE); - lookup_table_insert(w->lookup_table, lte); + } else { + return 0; } - res_entry->original_size = metadata_original_size; - res_entry->offset = metadata_offset; - res_entry->size = metadata_compressed_size; - res_entry->flags = WIM_RESHDR_FLAG_METADATA; - if (metadata_ctype != WIM_COMPRESSION_TYPE_NONE) - res_entry->flags |= WIM_RESHDR_FLAG_COMPRESSED; - return 0; } -static int write_file_resource(WIMStruct *w, const u8 hash[]) +int +extract_wim_resource_to_fd(const struct wim_lookup_table_entry *lte, + int fd, u64 size) { - /* Get the lookup entry for the file resource. */ - struct lookup_table_entry *lte; - - lte = lookup_resource(w->lookup_table, hash); - if (!lte) - return 0; - - /* No need to write file resources twice. (This indicates file - * resources that are part of a hard link set.) */ - if (++lte->out_refcnt != 1) - return 0; - - /* do not write empty resources */ - if (lte->resource_entry.original_size == 0) - return 0; - - int out_wim_ctype = wimlib_get_compression_type(w); - struct resource_entry *output_res_entry = <e->output_resource_entry; - u64 len; - FILE *in_fp; - FILE *out_fp = w->out_fp; - int ret = 0; - - /* Figure out if we can read the resource from the WIM file, or - * if we have to read it from the filesystem outside, or if it's a - * symbolic link with the data already in memory pointed to by a field - * of the lookup table entry. */ - if (lte->is_symlink) { - off_t offset = ftello(w->out_fp); - u64 new_size; - - if (offset == -1) { - ERROR_WITH_ERRNO("Could not get position in output " - "file"); - return WIMLIB_ERR_WRITE; - } - - wimlib_assert(lte->symlink_buf); - - len = lte->resource_entry.original_size; - - recompress_resource(in_fp, lte->symlink_buf, len, len, 0, - 0, out_fp, out_wim_ctype, &new_size); - output_res_entry->size = new_size; - output_res_entry->original_size = len; - output_res_entry->offset = offset; - output_res_entry->flags = (out_wim_ctype == WIM_COMPRESSION_TYPE_NONE) - ? 0 : WIM_RESHDR_FLAG_COMPRESSED; - } else if (lte->file_on_disk) { - - /* Read from disk (uncompressed) */ - - len = lte->resource_entry.original_size; + return extract_wim_resource(lte, size, extract_wim_chunk_to_fd, &fd); +} - in_fp = fopen(lte->file_on_disk, "rb"); - if (!in_fp) { - ERROR_WITH_ERRNO("Failed to open the file `%s'", - lte->file_on_disk); - return WIMLIB_ERR_OPEN; - } - ret = transfer_file_resource(in_fp, len, len, 0, - WIM_COMPRESSION_TYPE_NONE, out_fp, - out_wim_ctype, output_res_entry); - fclose(in_fp); - } else { - int in_wim_ctype; +static int +sha1_chunk(const void *buf, size_t len, void *ctx) +{ + sha1_update(ctx, buf, len); + return 0; +} - /* Read from input WIM (possibly compressed) */ +/* Calculate the SHA1 message digest of a stream. */ +int +sha1_resource(struct wim_lookup_table_entry *lte) +{ + int ret; + SHA_CTX sha_ctx; - /* It may be a different WIM file, in the case of - * exporting images from one WIM file to another */ - if (lte->other_wim_fp) { - /* Different WIM file. */ - in_fp = lte->other_wim_fp; - in_wim_ctype = lte->other_wim_ctype; - } else { - /* Same WIM file. */ - in_fp = w->fp; - in_wim_ctype = out_wim_ctype; - } - int input_res_ctype = resource_compression_type( - in_wim_ctype, - lte->resource_entry.flags); - - ret = transfer_file_resource(in_fp, - lte->resource_entry.size, - lte->resource_entry.original_size, - lte->resource_entry.offset, - input_res_ctype, - out_fp, - out_wim_ctype, - output_res_entry); - } + sha1_init(&sha_ctx); + ret = read_resource_prefix(lte, wim_resource_size(lte), + sha1_chunk, &sha_ctx, 0); + if (ret == 0) + sha1_final(lte->hash, &sha_ctx); return ret; } -/* - * Writes a dentry's resources to the output file. +/* + * Copies the file resource specified by the lookup table entry @lte from the + * input WIM to the output WIM that has its FILE * given by + * ((WIMStruct*)wim)->out_fp. * - * @dentry: The dentry for the file resource. - * @wim_p: A pointer to the WIMStruct. The fields of interest to this - * function are the input and output file streams and the lookup - * table, and the alternate data streams. + * The output_resource_entry, out_refcnt, and part_number fields of @lte are + * updated. * - * @return zero on success, nonzero on failure. + * (This function is confusing and should be refactored somehow.) */ -int write_dentry_resources(struct dentry *dentry, void *wim_p) +int +copy_resource(struct wim_lookup_table_entry *lte, void *wim) { - WIMStruct *w = wim_p; + WIMStruct *w = wim; int ret; - /* Directories don't need file resources. */ - if (dentry_is_directory(dentry)) - return 0; - - ret = write_file_resource(w, dentry->hash); - if (ret != 0) - return ret; - for (u16 i = 0; i < dentry->num_ads; i++) { - ret = write_file_resource(w, dentry->ads_entries[i].hash); - if (ret != 0) - return ret; + ret = write_wim_resource(lte, w->out_fd, + wim_resource_compression_type(lte), + <e->output_resource_entry, 0); + if (ret == 0) { + lte->out_refcnt = lte->refcnt; + lte->part_number = w->hdr.part_number; } - return 0; + return ret; } -