/*
* 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 <unistd.h>
+#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 <alloca.h>
+#endif
#include <errno.h>
+#include <fcntl.h>
+#include <stdarg.h>
+#include <stdlib.h>
+#include <unistd.h>
-
-/*
- * Reads all or part of a compressed resource into an in-memory buffer.
+/*
+ * Compressed resources
+ *
+ * A compressed resource in a WIM consists of a number of consecutive LZX or
+ * XPRESS-compressed chunks, each of which decompresses to 32768 bytes of data,
+ * except possibly the last, which always decompresses to any remaining bytes.
+ * In addition, immediately before the chunks, a table (the "chunk table")
+ * provides the offset, in bytes relative to the end of the chunk table, of the
+ * start of each compressed chunk, except for the first chunk which is omitted
+ * as it always has an offset of 0. Therefore, a compressed resource with N
+ * chunks will have a chunk table with N - 1 entries.
*
- * @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.
+ * Additional information:
*
- * Returns zero on success, nonzero on failure.
+ * - Entries in the chunk table are 4 bytes each, except if the uncompressed
+ * size of the resource is greater than 4 GiB, in which case the entries in
+ * the chunk table are 8 bytes each. In either case, the entries are unsigned
+ * little-endian integers.
+ *
+ * - The chunk table is included in the compressed size of the resource provided
+ * in the corresponding entry in the WIM's stream lookup table.
+ *
+ * - The compressed size of a chunk is never greater than the uncompressed size.
+ * From the compressor's point of view, chunks that would have compressed to a
+ * size greater than or equal to their original size are in fact stored
+ * uncompressed. From the decompresser's point of view, chunks with
+ * compressed size equal to their uncompressed size are in fact uncompressed.
+ *
+ * Furthermore, wimlib supports its own "pipable" WIM format, and for this the
+ * structure of compressed resources was modified to allow piped reading and
+ * writing. To make sequential writing possible, the chunk table is placed
+ * after the chunks rather than before the chunks, and to make sequential
+ * reading possible, each chunk is prefixed with a 4-byte header giving its
+ * compressed size as a 32-bit, unsigned, little-endian integer (less than or
+ * equal to 32768). Otherwise the details are the same.
*/
-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[])
-{
- 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;
+typedef int (*decompress_func_t)(const void *, unsigned, void *, unsigned);
- int (*decompress)(const void *, uint, void *, uint);
- /* Set the appropriate decompress function. */
- if (resource_ctype == WIM_COMPRESSION_TYPE_LZX)
- decompress = lzx_decompress;
+static decompress_func_t
+get_decompress_func(int ctype)
+{
+ if (ctype == WIMLIB_COMPRESSION_TYPE_LZX)
+ return wimlib_lzx_decompress;
else
- decompress = xpress_decompress;
-
- /* The structure of a compressed resource consists of a table of chunk
- * offsets followed by the chunks themselves. Each chunk consists of
- * compressed data, and there is one chunk for each WIM_CHUNK_SIZE =
- * 32768 bytes of the uncompressed file, with the last chunk having any
- * remaining bytes.
- *
- * 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.
- */
-
- /* Calculate how many chunks the resource conists 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. */
- u64 num_chunk_entries = num_chunks - 1;
+ return wimlib_xpress_decompress;
+}
+/*
+ * read_compressed_resource()-
+ *
+ * Read data from a compressed resource being read from a seekable WIM file.
+ * The resource may be either pipable or non-pipable.
+ *
+ * @flags may be:
+ *
+ * 0:
+ * Just do a normal read, decompressing the data if necessary.
+ *
+ * WIMLIB_READ_RESOURCE_FLAG_RAW_CHUNKS:
+ * Read the raw contents of the compressed chunks of the compressed
+ * resource. For pipable resources, this does *not* include the chunk
+ * headers. If a callback function is being used, it will be called once
+ * for each compressed chunk. For non-pipable resources, this mode
+ * excludes the chunk table. For pipable resources, this mode excludes the
+ * stream and chunk headers.
+ */
+static int
+read_compressed_resource(const struct wim_lookup_table_entry *lte,
+ u64 size, consume_data_callback_t cb,
+ void *ctx_or_buf, int flags, u64 offset)
+{
+ int ret;
- /* The index of the chunk that the read starts at. */
- u64 start_chunk = offset / WIM_CHUNK_SIZE;
- /* The byte offset at which the read starts, within the start chunk. */
- u64 start_chunk_offset = offset % WIM_CHUNK_SIZE;
+ /* Currently, reading raw compressed chunks is only guaranteed to work
+ * correctly when the full resource is requested. Furthermore, in such
+ * cases the requested size is specified as the compressed size, but
+ * here we change it to an uncompressed size to avoid confusing the rest
+ * of this function. */
+ if (flags & WIMLIB_READ_RESOURCE_FLAG_RAW_CHUNKS) {
+ wimlib_assert(offset == 0);
+ wimlib_assert(size == lte->resource_entry.size);
+ size = wim_resource_size(lte);
+ }
- /* The index of the chunk that contains the last byte of the read. */
- u64 end_chunk = (offset + len - 1) / WIM_CHUNK_SIZE;
- /* The byte offset of the last byte of the read, within the end chunk */
- u64 end_chunk_offset = (offset + len - 1) % WIM_CHUNK_SIZE;
+ wimlib_assert(offset + size <= wim_resource_size(lte));
- /* Number of chunks that are actually needed to read the requested part
- * of the file. */
- u64 num_needed_chunks = end_chunk - start_chunk + 1;
+ /* Handle the trivial case. */
+ if (size == 0)
+ return 0;
- /* If the end chunk is not the last chunk, an extra chunk entry is
- * needed because we need to know the offset of the chunk after the last
- * chunk read to figure out the size of the last read chunk. */
- 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];
-
- /* Set the implicit offset of the first chunk if it is included in the
- * needed chunks.
- *
- * Note: M$'s documentation includes a picture that shows the first
- * chunk starting right after the chunk entry table, labeled as offset
- * 0x10. However, in the actual file format, the offset is measured
- * from the end of the chunk entry table, so the first chunk has an
- * offset of 0. */
- if (start_chunk == 0)
- chunk_offsets[0] = 0;
+ /* Get the appropriate decompression function. */
+ decompress_func_t decompress =
+ get_decompress_func(wim_resource_compression_type(lte));
- /* According to M$'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;
+ /* Get the file descriptor for the WIM. */
+ struct filedes *in_fd = <e->wim->in_fd;
- /* Size of the full chunk table in the WIM file. */
- u64 chunk_table_size = chunk_entry_size * num_chunk_entries;
+ /* Calculate the number of chunks the resource is divided into. */
+ u64 num_chunks = wim_resource_chunks(lte);
- /* Read the needed chunk offsets from the table in the WIM file. */
+ /* Calculate the number of entries in the chunk table; it's one less
+ * than the number of chunks, since the first chunk has no entry. */
+ u64 num_chunk_entries = num_chunks - 1;
- /* Index, in the WIM file, of the first needed entry in the
- * chunk table. */
- u64 start_table_idx = (start_chunk == 0) ? 0 : start_chunk - 1;
+ /* Calculate the 0-based index of the chunk at which the read starts.
+ */
+ u64 start_chunk = offset / WIM_CHUNK_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) ?
- num_needed_chunks - 1 : num_needed_chunks;
-
- /* Skip over unneeded chunk table entries. */
- 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;
+ /* Calculate the offset, within the start chunk, of the first byte of
+ * the read. */
+ u64 start_offset_in_chunk = offset % WIM_CHUNK_SIZE;
+
+ /* Calculate the index of the chunk that contains the last byte of the
+ * read. */
+ u64 end_chunk = (offset + size - 1) / WIM_CHUNK_SIZE;
+
+ /* Calculate the offset, within the end chunk, of the last byte of the
+ * read. */
+ u64 end_offset_in_chunk = (offset + size - 1) % WIM_CHUNK_SIZE;
+
+ /* Calculate the number of chunk entries are actually needed to read the
+ * requested part of the resource. Include an entry for the first chunk
+ * even though that doesn't exist in the on-disk table, but take into
+ * account that if the last chunk required for the read is not the last
+ * chunk of the resource, an extra chunk entry is needed so that the
+ * compressed size of the last chunk of the read can be determined. */
+ u64 num_alloc_chunk_entries = end_chunk - start_chunk + 1;
+ if (end_chunk != num_chunks - 1)
+ num_alloc_chunk_entries++;
+
+ /* Set the size of each chunk table entry based on the resource's
+ * uncompressed size. */
+ u64 chunk_entry_size = (wim_resource_size(lte) > ((u64)1 << 32)) ? 8 : 4;
+
+ /* Calculate the size, in bytes, of the full chunk table. */
+ u64 chunk_table_size = num_chunk_entries * chunk_entry_size;
+
+ /* Allocate a buffer to hold a subset of the chunk table. It will only
+ * contain offsets for the chunks that are actually needed for this
+ * read. For speed, allocate the buffer on the stack unless it's too
+ * large. */
+ u64 *chunk_offsets;
+ bool chunk_offsets_malloced;
+ if (num_alloc_chunk_entries < 1024) {
+ chunk_offsets = alloca(num_alloc_chunk_entries * sizeof(u64));
+ chunk_offsets_malloced = false;
+ } else {
+ chunk_offsets = malloc(num_alloc_chunk_entries * sizeof(u64));
+ if (!chunk_offsets) {
+ ERROR("Failed to allocate chunk table "
+ "with %"PRIu64" entries", num_alloc_chunk_entries);
+ return WIMLIB_ERR_NOMEM;
+ }
+ chunk_offsets_malloced = true;
}
- /* Number of bytes we need to read from the chunk table. */
- size_t size = num_needed_chunk_entries * chunk_entry_size;
-
- u8 chunk_tab_buf[size];
-
- if (fread(chunk_tab_buf, 1, size, fp) != size)
- goto err;
-
- /* Now fill in chunk_offsets from the entries we have read in
- * chunk_tab_buf. */
-
- u64 *chunk_tab_p = chunk_offsets;
+ /* Set the implicit offset of the first chunk if it's included in the
+ * needed chunks. */
if (start_chunk == 0)
- chunk_tab_p++;
-
- if (chunk_entry_size == 4) {
- u32 *entries = (u32*)chunk_tab_buf;
- while (num_needed_chunk_entries--)
- *chunk_tab_p++ = to_le32(*entries++);
- } else {
- u64 *entries = (u64*)chunk_tab_buf;
- while (num_needed_chunk_entries--)
- *chunk_tab_p++ = to_le64(*entries++);
- }
+ chunk_offsets[0] = 0;
- /* Done with the chunk table now. We must now seek to the first chunk
- * that is needed for the read. */
+ /* Calculate the index of the first needed entry in the chunk table. */
+ u64 start_table_idx = (start_chunk == 0) ? 0 : start_chunk - 1;
- 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;
+ /* Calculate the number of entries that need to be read from the chunk
+ * table. */
+ u64 num_needed_chunk_entries = (start_chunk == 0) ?
+ num_alloc_chunk_entries - 1 : num_alloc_chunk_entries;
+
+ /* Calculate the number of bytes of data that need to be read from the
+ * chunk table. */
+ size_t chunk_table_needed_size =
+ num_needed_chunk_entries * chunk_entry_size;
+ if ((u64)chunk_table_needed_size !=
+ num_needed_chunk_entries * chunk_entry_size)
+ {
+ ERROR("Compressed read request too large to fit into memory!");
+ ret = WIMLIB_ERR_NOMEM;
+ goto out_free_chunk_offsets;
}
- /* Pointer to current position in the output buffer for uncompressed
- * data. */
- u8 *out_p = (u8*)contents_ret;
-
- /* 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
- * size in the worst-case. This assumption is valid only if chunks that
- * 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];
+ /* Calculate the byte offset, in the WIM file, of the first chunk table
+ * entry to read. Take into account that if the WIM file is in the
+ * special "pipable" format, then the chunk table is at the end of the
+ * resource, not the beginning. */
+ u64 file_offset_of_needed_chunk_entries =
+ lte->resource_entry.offset + (start_table_idx *
+ chunk_entry_size);
+ if (lte->is_pipable)
+ file_offset_of_needed_chunk_entries += lte->resource_entry.size -
+ chunk_table_size;
+
+ /* Read the needed chunk table entries into the end of the chunk_offsets
+ * buffer. */
+ void *chunk_tab_data = (u8*)&chunk_offsets[num_alloc_chunk_entries] -
+ chunk_table_needed_size;
+ ret = full_pread(in_fd, chunk_tab_data, chunk_table_needed_size,
+ file_offset_of_needed_chunk_entries);
+ if (ret)
+ goto read_error;
+ /* Now fill in chunk_offsets from the entries we have read in
+ * chunk_tab_data. Careful: chunk_offsets aliases chunk_tab_data, which
+ * breaks C's aliasing rules when we read 32-bit integers and store
+ * 64-bit integers. But since the operations are safe as long as the
+ * compiler doesn't mess with their order, we use the gcc may_alias
+ * extension to tell the compiler that loads from the 32-bit integers
+ * may alias stores to the 64-bit integers. */
+ {
+ typedef le64 __attribute__((may_alias)) aliased_le64_t;
+ typedef le32 __attribute__((may_alias)) aliased_le32_t;
+ u64 *chunk_offsets_p = chunk_offsets;
+ u64 i;
+
+ if (start_chunk == 0)
+ chunk_offsets_p++;
+
+ if (chunk_entry_size == 4) {
+ aliased_le32_t *raw_entries = (aliased_le32_t*)chunk_tab_data;
+ for (i = 0; i < num_needed_chunk_entries; i++)
+ chunk_offsets_p[i] = le32_to_cpu(raw_entries[i]);
+ } else {
+ aliased_le64_t *raw_entries = (aliased_le64_t*)chunk_tab_data;
+ for (i = 0; i < num_needed_chunk_entries; i++)
+ chunk_offsets_p[i] = le64_to_cpu(raw_entries[i]);
+ }
+ }
- /* Decompress all the chunks. */
+ /* Calculate file offset of the first chunk that needs to be read. N.B.
+ * if the resource is pipable, the entries in the chunk table do *not*
+ * include the chunk headers. */
+ u64 cur_read_offset = lte->resource_entry.offset + chunk_offsets[0];
+ if (!lte->is_pipable)
+ cur_read_offset += chunk_table_size;
+ else
+ cur_read_offset += start_chunk *
+ sizeof(struct pwm_chunk_hdr);
+
+ /* If using a callback function, allocate a temporary buffer that will
+ * be used to pass data to it. If writing directly to a buffer instead,
+ * arrange to write data directly into it. */
+ u8 *out_p;
+ if (cb)
+ out_p = alloca(WIM_CHUNK_SIZE);
+ else
+ out_p = ctx_or_buf;
+
+ /* Unless the raw compressed data was requested, allocate a temporary
+ * buffer for reading compressed chunks, each of which can be at most
+ * WIM_CHUNK_SIZE - 1 bytes. This excludes compressed chunks that are a
+ * full WIM_CHUNK_SIZE bytes, which are handled separately. */
+ void *compressed_buf;
+ if (!(flags & WIMLIB_READ_RESOURCE_FLAG_RAW_CHUNKS))
+ compressed_buf = alloca(WIM_CHUNK_SIZE - 1);
+
+ /* Read, and possibly decompress, each needed chunk, either writing the
+ * data directly into the @ctx_or_buf buffer or passing it to the @cb
+ * callback function. */
for (u64 i = start_chunk; i <= end_chunk; i++) {
- DEBUG2("Chunk %"PRIu64" (start %"PRIu64", end %"PRIu64").",
- i, start_chunk, end_chunk);
+ /* If the resource is pipable, skip the chunk header. */
+ if (lte->is_pipable)
+ cur_read_offset += sizeof(struct pwm_chunk_hdr);
/* Calculate the sizes of the compressed chunk and of the
- * uncompressed chunk. */
- uint compressed_chunk_size, uncompressed_chunk_size;
+ * uncompressed chunk. */
+ 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] -
+ /* Not the last chunk. Compressed size is given by
+ * difference of chunk table entries; uncompressed size
+ * is always 32768 bytes. */
+ compressed_chunk_size = chunk_offsets[i + 1 - start_chunk] -
chunk_offsets[i - start_chunk];
uncompressed_chunk_size = WIM_CHUNK_SIZE;
} else {
- /* The last compressed chunk consists of the remaining
- * 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.
- *
- * Note that the resource_compressed_size includes the
- * chunk table, so the size of it must be subtracted. */
- compressed_chunk_size = resource_compressed_size -
+ /* Last chunk. Compressed size is the remaining size in
+ * the compressed resource; uncompressed size is the
+ * remaining size in the uncompressed resource. */
+ compressed_chunk_size = lte->resource_entry.size -
chunk_table_size -
chunk_offsets[i - start_chunk];
+ if (lte->is_pipable)
+ compressed_chunk_size -= num_chunks *
+ sizeof(struct pwm_chunk_hdr);
- uncompressed_chunk_size = resource_uncompressed_size %
- WIM_CHUNK_SIZE;
-
- /* If the remainder is 0, the last chunk actually
- * uncompresses to a full WIM_CHUNK_SIZE bytes. */
- if (uncompressed_chunk_size == 0)
+ if (wim_resource_size(lte) % WIM_CHUNK_SIZE == 0)
uncompressed_chunk_size = WIM_CHUNK_SIZE;
+ else
+ uncompressed_chunk_size = wim_resource_size(lte) %
+ 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)
- start_offset = start_chunk_offset;
- else
- start_offset = 0;
- u64 end_offset;
- if (i == end_chunk)
- end_offset = end_chunk_offset;
- 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);
-
- /* 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;
- }
- }
- if (fread(out_p, 1, partial_chunk_size, fp) !=
- partial_chunk_size)
- goto err;
+ /* Calculate how much of this chunk needs to be read. */
+
+ unsigned partial_chunk_size;
+ u64 start_offset = 0;
+ u64 end_offset = WIM_CHUNK_SIZE - 1;
+
+ if (flags & WIMLIB_READ_RESOURCE_FLAG_RAW_CHUNKS) {
+ partial_chunk_size = compressed_chunk_size;
} else {
- /* Compressed chunk */
- int ret;
+ if (i == start_chunk)
+ start_offset = start_offset_in_chunk;
- /* Read the compressed data into compressed_buf. */
- if (fread(compressed_buf, 1, compressed_chunk_size,
- fp) != compressed_chunk_size)
- goto err;
+ if (i == end_chunk)
+ end_offset = end_offset_in_chunk;
- /* For partial chunks we must buffer the uncompressed
- * data because we don't need all of it. */
- if (is_partial_chunk) {
+ partial_chunk_size = end_offset + 1 - start_offset;
+ }
+
+ if (compressed_chunk_size == uncompressed_chunk_size ||
+ (flags & WIMLIB_READ_RESOURCE_FLAG_RAW_CHUNKS))
+ {
+ /* Chunk stored uncompressed, or reading raw chunk data. */
+ ret = full_pread(in_fd,
+ cb ? out_p + start_offset : out_p,
+ partial_chunk_size,
+ cur_read_offset + start_offset);
+ if (ret)
+ goto read_error;
+ } else {
+ /* Compressed chunk and not doing raw read. */
+
+ /* Read the compressed data into compressed_buf. */
+ ret = full_pread(in_fd,
+ compressed_buf,
+ compressed_chunk_size,
+ cur_read_offset);
+ if (ret)
+ goto read_error;
+
+ /* 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 (partial_chunk_size != uncompressed_chunk_size &&
+ cb == NULL)
+ {
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;
+ ret = (*decompress)(compressed_buf,
+ compressed_chunk_size,
+ uncompressed_buf,
+ uncompressed_chunk_size);
+ if (ret) {
+ ERROR("Failed to decompress data.");
+ ret = WIMLIB_ERR_DECOMPRESSION;
+ errno = EINVAL;
+ goto out_free_chunk_offsets;
+ }
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;
+ ret = (*decompress)(compressed_buf,
+ compressed_chunk_size,
+ out_p,
+ uncompressed_chunk_size);
+ if (ret) {
+ ERROR("Failed to decompress data.");
+ ret = WIMLIB_ERR_DECOMPRESSION;
+ errno = EINVAL;
+ goto out_free_chunk_offsets;
+ }
}
}
-
- /* 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_free_chunk_offsets;
+ } 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_free_chunk_offsets:
+ if (chunk_offsets_malloced)
+ FREE(chunk_offsets);
+ 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");
+ goto out_free_chunk_offsets;
}
-/*
- * Reads uncompressed data from an open file stream.
- */
-int read_uncompressed_resource(FILE *fp, u64 offset, u64 len,
- u8 contents_ret[])
+/* Skip over the chunk table at the end of pipable, compressed resource being
+ * read from a pipe. */
+static int
+skip_chunk_table(const struct wim_lookup_table_entry *lte,
+ struct filedes *in_fd)
{
- 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;
- }
- 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;
+ u64 num_chunk_entries = wim_resource_chunks(lte) - 1;
+ u64 chunk_entry_size = (wim_resource_size(lte) > ((u64)1 << 32)) ? 8 : 4;
+ u64 chunk_table_size = num_chunk_entries * chunk_entry_size;
+ int ret;
+
+ if (num_chunk_entries != 0) {
+ u8 dummy;
+ ret = full_pread(in_fd, &dummy, 1,
+ in_fd->offset + chunk_table_size - 1);
+ if (ret)
+ return ret;
}
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)
+/* Read and decompress data from a compressed, pipable resource being read from
+ * a pipe. */
+static int
+read_pipable_resource(const struct wim_lookup_table_entry *lte,
+ u64 size, consume_data_callback_t cb,
+ void *ctx_or_buf, int flags, u64 offset)
{
- 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;
+ struct filedes *in_fd;
+ decompress_func_t decompress;
+ int ret;
+ u8 chunk[WIM_CHUNK_SIZE];
+ u8 cchunk[WIM_CHUNK_SIZE - 1];
+
+ /* Get pointers to appropriate decompression function and the input file
+ * descriptor. */
+ decompress = get_decompress_func(wim_resource_compression_type(lte));
+ in_fd = <e->wim->in_fd;
+
+ /* This function currently assumes the entire resource is being read at
+ * once and that the raw compressed data isn't being requested. This is
+ * based on the fact that this function currently only gets called
+ * during the operation of wimlib_extract_image_from_pipe(). */
+ wimlib_assert(!(flags & WIMLIB_READ_RESOURCE_FLAG_RAW));
+ wimlib_assert(offset == 0);
+ wimlib_assert(size == wim_resource_size(lte));
+ wimlib_assert(in_fd->offset == lte->resource_entry.offset);
+
+ for (offset = 0; offset < size; offset += WIM_CHUNK_SIZE) {
+ struct pwm_chunk_hdr chunk_hdr;
+ u32 chunk_size;
+ u32 cchunk_size;
+ u8 *res_chunk;
+ u32 res_chunk_size;
+
+ /* Calculate uncompressed size of next chunk. */
+ chunk_size = min(WIM_CHUNK_SIZE, size - offset);
+
+ /* Read the compressed size of the next chunk from the chunk
+ * header. */
+ ret = full_read(in_fd, &chunk_hdr, sizeof(chunk_hdr));
+ if (ret)
+ goto read_error;
+
+ cchunk_size = le32_to_cpu(chunk_hdr.compressed_size);
+
+ if (cchunk_size > WIM_CHUNK_SIZE) {
+ errno = EINVAL;
+ ret = WIMLIB_ERR_INVALID_PIPABLE_WIM;
+ goto invalid;
}
- 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);
- }
-}
+ /* Read chunk data. */
+ ret = full_read(in_fd, cchunk, cchunk_size);
+ if (ret)
+ goto read_error;
-/*
- * 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)
-{
- u64 num_chunks;
- u64 n;
- u8 buf[min(size, WIM_CHUNK_SIZE)];
- int res_ctype;
- u64 offset;
- u64 i;
- int ret;
+ if (flags & WIMLIB_READ_RESOURCE_FLAG_SEEK_ONLY)
+ continue;
- 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;
+ /* Decompress chunk if needed. Uncompressed size same
+ * as compressed size means the chunk is uncompressed.
+ */
+ res_chunk_size = chunk_size;
+ if (cchunk_size == chunk_size) {
+ res_chunk = cchunk;
+ } else {
+ ret = (*decompress)(cchunk, cchunk_size,
+ chunk, chunk_size);
+ if (ret) {
+ errno = EINVAL;
+ ret = WIMLIB_ERR_DECOMPRESSION;
+ goto invalid;
}
+ res_chunk = chunk;
}
- ret = read_resource(w->fp, entry->size, entry->original_size,
- entry->offset, res_ctype, n, offset, buf);
- if (ret != 0)
- return ret;
-
- if (full_write(fd, buf, n) != n)
- return WIMLIB_ERR_WRITE;
- offset += n;
+ /* Feed the uncompressed data into the callback function or copy
+ * it into the provided buffer. */
+ if (cb) {
+ ret = cb(res_chunk, res_chunk_size, ctx_or_buf);
+ if (ret)
+ return ret;
+ } else {
+ ctx_or_buf = mempcpy(ctx_or_buf, res_chunk,
+ res_chunk_size);
+ }
}
+
+ ret = skip_chunk_table(lte, in_fd);
+ if (ret)
+ goto read_error;
+ return 0;
+
+read_error:
+ ERROR_WITH_ERRNO("Error reading compressed file resource");
+ return ret;
+
+invalid:
+ ERROR("Compressed file resource is invalid");
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.
+/*
+ * read_partial_wim_resource()-
+ *
+ * Read a range of data from a uncompressed or compressed resource in a WIM
+ * file. Data is written into a buffer or fed into a callback function, as
+ * documented in read_resource_prefix().
+ *
+ * @flags can be:
+ *
+ * 0:
+ * Just do a normal read, decompressing the data if necessary. @size and
+ * @offset are interpreted relative to the uncompressed contents of the
+ * stream.
+ *
+ * WIMLIB_READ_RESOURCE_FLAG_RAW_FULL:
+ * Only valid when the resource is compressed: Read the raw contents of
+ * the compressed resource. If the resource is non-pipable, this includes
+ * the chunk table as well as the compressed chunks. If the resource is
+ * pipable, this includes the compressed chunks--- including the chunk
+ * headers--- and the chunk table. The stream header is still *not*
+ * included.
+ *
+ * In this mode, @offset is relative to the beginning of the raw contents
+ * of the compressed resource--- that is, the chunk table if the resource
+ * is non-pipable, or the header for the first compressed chunk if the
+ * resource is pipable. @size is the number of raw bytes to read, which
+ * must not overrun the end of the resource. For example, if @offset is 0,
+ * then @size can be at most the raw size of the compressed resource
+ * (@lte->resource_entry.size).
*
- * The output_resource_entry, out_refcnt, and part_number fields of @lte are
- * updated.
+ * WIMLIB_READ_RESOURCE_FLAG_RAW_CHUNKS:
+ * Only valid when the resource is compressed and is not being read from a
+ * pipe: Read the raw contents of the compressed chunks of the compressed
+ * resource. For pipable resources, this does *not* include the chunk
+ * headers. If a callback function is being used, it will be called once
+ * for each compressed chunk. The chunk table is excluded. Also, for
+ * pipable resources, the stream and chunk headers are excluded. In this
+ * mode, @size must be exactly the raw size of the compressed resource
+ * (@lte->resource_entry.size) and @offset must be 0.
*
- * Metadata resources are not copied (they are handled elsewhere for joining and
- * splitting).
+ * WIMLIB_READ_RESOURCE_FLAG_SEEK_ONLY:
+ * Only valid when the resource is being read from a pipe: Skip over the
+ * requested data rather than feed it to the callback function or write it
+ * into the buffer. No decompression is done.
+ * WIMLIB_READ_RESOURCE_FLAG_RAW_* may not be combined with this flag.
+ * @offset must be 0 and @size must be the uncompressed size of the
+ * resource.
+ *
+ * Return values:
+ * WIMLIB_ERR_SUCCESS (0)
+ * WIMLIB_ERR_READ (errno set)
+ * WIMLIB_ERR_UNEXPECTED_END_OF_FILE (errno set to 0)
+ * WIMLIB_ERR_NOMEM (errno set to ENOMEM)
+ * WIMLIB_ERR_DECOMPRESSION (errno set to EINVAL)
+ * WIMLIB_ERR_INVALID_PIPABLE_WIM (errno set to EINVAL)
+ *
+ * or other error code returned by the @cb function.
*/
-int copy_resource(struct lookup_table_entry *lte, void *w)
+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)
{
- if ((lte->resource_entry.flags & WIM_RESHDR_FLAG_METADATA) &&
- !((WIMStruct*)w)->write_metadata) {
- return 0;
- }
-
- FILE *in_fp = ((WIMStruct*)w)->fp;
- FILE *out_fp = ((WIMStruct*)w)->out_fp;
+ struct filedes *in_fd;
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));
+ /* Make sure the resource is actually located in a WIM file and is not
+ * somewhere else. */
+ wimlib_assert(lte->resource_location == RESOURCE_IN_WIM);
+
+ /* Retrieve input file descriptor for the WIM file. */
+ in_fd = <e->wim->in_fd;
+
+ /* Don't allow raw reads (either full or chunks) of uncompressed
+ * resources. */
+ wimlib_assert(!(flags & WIMLIB_READ_RESOURCE_FLAG_RAW) ||
+ resource_is_compressed(<e->resource_entry));
+
+ /* Don't allow seek-only reads unless reading from a pipe; also don't
+ * allow combining SEEK_ONLY with either RAW flag. */
+ wimlib_assert(!(flags & WIMLIB_READ_RESOURCE_FLAG_SEEK_ONLY) ||
+ (!filedes_is_seekable(in_fd) &&
+ !(flags & WIMLIB_READ_RESOURCE_FLAG_RAW)));
+
+ DEBUG("Reading WIM resource: %"PRIu64" @ +%"PRIu64" "
+ "from %"PRIu64" @ +%"PRIu64" (readflags 0x%08x, resflags 0x%02x%s)",
+ size, offset,
+ lte->resource_entry.original_size, lte->resource_entry.offset,
+ flags, lte->resource_entry.flags,
+ (lte->is_pipable ? ", pipable" : ""));
+
+ if ((flags & WIMLIB_READ_RESOURCE_FLAG_RAW_FULL) ||
+ !resource_is_compressed(<e->resource_entry))
+ {
+ /* Reading raw resource contents or reading uncompressed
+ * resource. */
+ wimlib_assert(offset + size <= lte->resource_entry.size);
+ offset += lte->resource_entry.offset;
+ if (flags & WIMLIB_READ_RESOURCE_FLAG_SEEK_ONLY) {
+ if (lte->resource_entry.size != 0) {
+ u8 dummy;
+ ret = full_pread(in_fd, &dummy, 1,
+ offset + lte->resource_entry.size - 1);
+ if (ret)
+ goto read_error;
+ }
+ } else 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);
+ ret = full_pread(in_fd, buf, bytes_to_read,
+ offset);
+ if (ret)
+ goto read_error;
+ ret = cb(buf, bytes_to_read, ctx_or_buf);
+ if (ret)
+ goto out;
+ size -= bytes_to_read;
+ offset += bytes_to_read;
+ }
+ } else {
+ /* Send data directly to a buffer */
+ ret = full_pread(in_fd, ctx_or_buf, size, offset);
+ if (ret)
+ goto read_error;
+ }
+ ret = 0;
+ } else if (lte->is_pipable && !filedes_is_seekable(in_fd)) {
+ /* Reading compressed, pipable resource from pipe. */
+ ret = read_pipable_resource(lte, size, cb,
+ ctx_or_buf, flags, offset);
+ } else {
+ /* Reading compressed, possibly pipable resource from seekable
+ * file. */
+ ret = read_compressed_resource(lte, size, cb,
+ ctx_or_buf, flags, offset);
+ }
+ goto out;
- lte->output_resource_entry.offset = new_offset;
- lte->out_refcnt = lte->refcnt;
- lte->part_number = ((WIMStruct*)w)->hdr.part_number;
- return 0;
+read_error:
+ ERROR_WITH_ERRNO("Error reading data from WIM");
+out:
+ 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;
+ struct filedes fd;
+ int raw_fd;
- 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;
- }
- /* 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;
- }
+ DEBUG("Reading %"PRIu64" bytes from \"%"TS"\"",
+ size, lte->file_on_disk);
- if (fwrite(buf, 1, n, out_fp) != n) {
- ERROR_WITH_ERRNO("Error copying data between files");
- return WIMLIB_ERR_WRITE;
+ raw_fd = open(filename, O_RDONLY);
+ if (raw_fd < 0) {
+ ERROR_WITH_ERRNO("Can't open \"%"TS"\"", filename);
+ return WIMLIB_ERR_OPEN;
+ }
+ filedes_init(&fd, raw_fd);
+ 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);
+ ret = full_read(&fd, buf, bytes_to_read);
+ if (ret)
+ goto read_error;
+ ret = cb(buf, bytes_to_read, ctx_or_buf);
+ if (ret)
+ goto out_close;
+ size -= bytes_to_read;
}
- len -= n;
+ } else {
+ /* Send data directly to a buffer */
+ ret = full_read(&fd, ctx_or_buf, size);
+ if (ret)
+ goto read_error;
}
- return 0;
-}
+ ret = 0;
+ goto out_close;
+read_error:
+ ERROR_WITH_ERRNO("Error reading \"%"TS"\"", filename);
+out_close:
+ filedes_close(&fd);
+ return ret;
+}
+#endif /* !__WIN32__ */
-/*
- * 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)
+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;
- 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) {
+ while (size) {
+ size_t chunk_size = min(WIM_CHUNK_SIZE, size);
+ ret = cb(inbuf, chunk_size, ctx_or_buf);
+ if (ret)
+ return ret;
+ size -= chunk_size;
+ inbuf += chunk_size;
}
+ } else {
+ memcpy(ctx_or_buf, inbuf, size);
}
return 0;
}
-/*
- * 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.
+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);
+
+/*
+ * read_resource_prefix()-
+ *
+ * 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 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.
+ * 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 set as documented in
+ * read_partial_wim_resource(). Otherwise @flags are ignored.
*/
-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)
+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;
- 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)
- 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;
- }
-
- 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]);
- }
- 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;
+ static const read_resource_prefix_handler_t handlers[] = {
+ [RESOURCE_IN_WIM] = read_wim_resource_prefix,
+ #ifdef __WIN32__
+ [RESOURCE_IN_FILE_ON_DISK] = read_win32_file_prefix,
+ #else
+ [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_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);
}
-int write_resource_from_memory(const u8 resource[], int out_ctype,
- u64 resource_original_size, FILE *out_fp,
- u64 *resource_size_ret)
+int
+read_full_resource_into_buf(const struct wim_lookup_table_entry *lte,
+ void *buf)
{
- 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);
- }
+ return read_resource_prefix(lte, wim_resource_size(lte), NULL, buf, 0);
}
-
-/*
- * Transfers a file resource from a FILE* opened for reading to a FILE* opened
- * for writing, possibly changing the compression type.
- *
- * @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.
- */
-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_full_resource_into_alloc_buf(const struct wim_lookup_table_entry *lte,
+ void **buf_ret)
{
int ret;
+ void *buf;
- /* Handle zero-length files */
- if (original_size == 0) {
- memset(output_res_entry, 0, sizeof(*output_res_entry));
- return 0;
- }
-
- /* 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;
+ if ((size_t)lte->resource_entry.original_size !=
+ lte->resource_entry.original_size)
+ {
+ ERROR("Can't read %"PRIu64" byte resource into "
+ "memory", lte->resource_entry.original_size);
+ return WIMLIB_ERR_NOMEM;
}
- output_res_entry->offset = (u64)out_offset;
- if (output_ctype == input_ctype) {
- /* The same compression types; simply copy the resource. */
-
- 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;
- }
+ buf = MALLOC(lte->resource_entry.original_size);
+ if (!buf)
+ return WIMLIB_ERR_NOMEM;
+ ret = read_full_resource_into_buf(lte, buf);
+ if (ret) {
+ FREE(buf);
+ return ret;
}
- 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;
+ *buf_ret = buf;
return 0;
}
-/*
- * 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.
- *
- * @return: Zero on success, nonzero on failure.
- */
-int read_metadata_resource(FILE *fp, int wim_ctype, struct image_metadata *imd)
+int
+res_entry_to_data(const struct resource_entry *res_entry,
+ WIMStruct *wim, void **buf_ret)
{
- 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;
+ struct wim_lookup_table_entry *lte;
- res_entry = &imd->metadata_lte->resource_entry;
+ lte = new_lookup_table_entry();
+ if (!lte)
+ return WIMLIB_ERR_NOMEM;
- DEBUG("Reading metadata resource: length = %"PRIu64", "
- "offset = %"PRIu64"",
- res_entry->original_size, res_entry->offset);
+ copy_resource_entry(<e->resource_entry, res_entry);
+ lte->unhashed = 1;
+ lte->part_number = wim->hdr.part_number;
+ lte_init_wim(lte, wim);
- 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);
+ ret = read_full_resource_into_alloc_buf(lte, buf_ret);
+ free_lookup_table_entry(lte);
+ return ret;
+}
- if (!buf) {
- ERROR("Failed to allocate %"PRIu64" bytes for uncompressed "
- "metadata resource", res_entry->original_size);
- return WIMLIB_ERR_NOMEM;
- }
+struct extract_ctx {
+ SHA_CTX sha_ctx;
+ consume_data_callback_t extract_chunk;
+ void *extract_chunk_arg;
+};
- /* 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;
- }
+static int
+extract_chunk_sha1_wrapper(const void *chunk, size_t chunk_size,
+ void *_ctx)
+{
+ struct extract_ctx *ctx = _ctx;
- 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;
-
- DEBUG("Reading 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;
-
- DEBUG("Calculating dentry full paths");
- /* 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;
-
- DEBUG("Building link group table");
- /* Build hash table that maps hard link group IDs to dentry sets */
- 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;
-
- DEBUG("Freeing duplicate ADS entries in link group table");
- ret = link_groups_free_duplicate_data(lgt);
- if (ret != 0)
- goto out_free_lgt;
- DEBUG("Done reading image metadata");
-
- imd->lgt = lgt;
- imd->security_data = sd;
- imd->root_dentry = dentry;
- goto out_free_buf;
-out_free_lgt:
- free_link_group_table(lgt);
-out_free_dentry_tree:
- free_dentry_tree(dentry, NULL);
-out_free_security_data:
- free_security_data(sd);
-out_free_buf:
- FREE(buf);
- return ret;
+ sha1_update(&ctx->sha_ctx, chunk, chunk_size);
+ return ctx->extract_chunk(chunk, chunk_size, ctx->extract_chunk_arg);
}
-/* Write the metadata resource for the current image. */
-int write_metadata_resource(WIMStruct *w)
+/* 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.
+ *
+ * @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)
{
- 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)
- 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;
+ 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)) {
+ if (wimlib_print_errors) {
+ 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!");
+ }
+ ret = WIMLIB_ERR_INVALID_RESOURCE_HASH;
+ }
+ }
+ } else {
+ /* Don't do SHA1 */
+ ret = read_resource_prefix(lte, size, extract_chunk,
+ extract_chunk_arg, 0);
}
+ return ret;
+}
- p = write_security_data(sd, buf);
-
- DEBUG("Writing dentry tree.");
- p = write_dentry_tree(root, p);
+static int
+extract_wim_chunk_to_fd(const void *buf, size_t len, void *_fd_p)
+{
+ struct filedes *fd = _fd_p;
+ int ret = full_write(fd, buf, len);
+ if (ret)
+ ERROR_WITH_ERRNO("Error writing to file descriptor");
+ return ret;
+}
- /* 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);
+int
+extract_wim_resource_to_fd(const struct wim_lookup_table_entry *lte,
+ struct filedes *fd, u64 size)
+{
+ return extract_wim_resource(lte, size, extract_wim_chunk_to_fd, fd);
+}
- ret = write_resource_from_memory(buf,
- metadata_ctype,
- metadata_original_size,
- out,
- &metadata_compressed_size);
- FREE(buf);
- if (ret != 0)
- return ret;
- DEBUG("Updating metadata lookup table entry (size %zu)",
- metadata_original_size);
-
- /* 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);
- }
- 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;
+static int
+sha1_chunk(const void *buf, size_t len, void *ctx)
+{
+ sha1_update(ctx, buf, len);
return 0;
}
-static int write_file_resource(WIMStruct *w, const u8 hash[])
+/* Calculate the SHA1 message digest of a stream. */
+int
+sha1_resource(struct wim_lookup_table_entry *lte)
{
- /* 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. */
- 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;
-
- ret = recompress_resource(NULL, 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;
-
- 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;
-
- /* Read from input WIM (possibly compressed) */
+ 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.
- *
- * @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.
- *
- * @return zero on success, nonzero on failure.
- */
-int write_dentry_resources(struct dentry *dentry, void *wim_p)
+/* 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)
{
- WIMStruct *w = wim_p;
- 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;
+ /* 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 (entry->original_size & 0xc000000000000000ULL) {
+ WARNING("Truncating original_size in resource entry");
+ entry->original_size &= 0x3fffffffffffffffULL;
}
- return 0;
}
+/* 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)
+{
+ /* 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);
+}