* wimlib; if not, see http://www.gnu.org/licenses/.
*/
-#include "wimlib_internal.h"
-#include "dentry.h"
-#include "lookup_table.h"
-#include "buffer_io.h"
-#include "sha1.h"
+#ifdef HAVE_CONFIG_H
+# include "config.h"
+#endif
+
+#include "wimlib.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__
-# include "win32.h"
+/* for read_win32_file_prefix(), read_win32_encrypted_file_prefix() */
+# include "wimlib/win32.h"
#endif
-#include <errno.h>
-#include <stdarg.h>
-#include <stdlib.h>
-#include <unistd.h>
-#include <fcntl.h>
+#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 <stdlib.h>
+#include <unistd.h>
/*
- * Reads all or part of a compressed WIM resource.
+ * Compressed WIM resources
+ *
+ * A compressed resource in a WIM consists of a number of compressed chunks,
+ * each of which decompresses to a fixed chunk size (given in the WIM header;
+ * usually 32768) 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.
+ *
+ * Additional information:
+ *
+ * - 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.
*
- * Returns zero on success, nonzero on failure.
+ * - 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. Otherwise the
+ * details are the same.
*/
+
+
+/* Decompress the specified chunk that uses the specified compression type
+ * @ctype, part of a WIM with default chunk size @wim_chunk_size. For LZX the
+ * separate @wim_chunk_size is needed because it determines the window size used
+ * for LZX compression. */
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)
+decompress(const void *cchunk, unsigned clen, void *uchunk, unsigned ulen,
+ int ctype, u32 wim_chunk_size)
{
- int ret;
+ switch (ctype) {
+ case WIMLIB_COMPRESSION_TYPE_LZX:
+ return wimlib_lzx_decompress2(cchunk, clen,
+ uchunk, ulen, wim_chunk_size);
+ case WIMLIB_COMPRESSION_TYPE_XPRESS:
+ return wimlib_xpress_decompress(cchunk, clen,
+ uchunk, ulen);
+ case WIMLIB_COMPRESSION_TYPE_LZMS:
+ return wimlib_lzms_decompress(cchunk, clen, uchunk, ulen);
+ default:
+ wimlib_assert(0);
+ return -1;
+ }
+}
- /* Trivial case */
- if (len == 0)
- return 0;
-
- int (*decompress)(const void *, unsigned, void *, unsigned);
- /* Set the appropriate decompress function. */
- if (resource_ctype == WIMLIB_COMPRESSION_TYPE_LZX)
- decompress = wimlib_lzx_decompress;
- else
- 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
- * 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 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. */
- u64 num_chunk_entries = num_chunks - 1;
-
-
- /* 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;
-
- /* 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;
-
- /* Number of chunks that are actually needed to read the requested part
- * of the file. */
- u64 num_needed_chunks = end_chunk - start_chunk + 1;
-
- /* 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++;
-
- /* 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 < 1000) {
- 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;
+struct data_range {
+ u64 offset;
+ u64 size;
+};
+
+/* Alternate chunk table format for resources with WIM_RESHDR_FLAG_CONCAT set.
+ */
+struct alt_chunk_table_header_disk {
+ /* Uncompressed size of the resource. */
+ le64 res_usize;
+
+ /* Number of bytes each compressed chunk decompresses into, except
+ * possibly the last which decompresses into the remainder. */
+ le32 chunk_size;
+
+ /* ??? */
+ le32 unknown;
+
+ /* This header is directly followed by a table of compressed sizes of
+ * the chunks. */
+} _packed_attribute;
+
+/* Read data from a compressed WIM resource. */
+static int
+read_compressed_wim_resource(const struct wim_resource_spec * const rspec,
+ const struct data_range * const ranges,
+ const size_t num_ranges,
+ const consume_data_callback_t cb,
+ void * const cb_ctx,
+ const bool raw_chunks_mode)
+{
+ int ret;
+ int errno_save;
+
+ u64 *chunk_offsets = NULL;
+ u8 *ubuf = NULL;
+ void *cbuf = NULL;
+ bool chunk_offsets_malloced = false;
+ bool ubuf_malloced = false;
+ bool cbuf_malloced = false;
+
+ /* Sanity checks */
+ wimlib_assert(rspec != NULL);
+ wimlib_assert(rspec->ctype != WIMLIB_COMPRESSION_TYPE_NONE);
+ wimlib_assert(is_power_of_2(rspec->cchunk_size));
+ wimlib_assert(cb != NULL);
+ wimlib_assert(num_ranges != 0);
+ for (size_t i = 0; i < num_ranges; i++) {
+ wimlib_assert(ranges[i].size != 0);
+ wimlib_assert(ranges[i].offset + ranges[i].size >= ranges[i].size);
+ wimlib_assert(ranges[i].offset + ranges[i].size <= rspec->uncompressed_size);
}
+ for (size_t i = 0; i < num_ranges - 1; i++)
+ wimlib_assert(ranges[i].offset + ranges[i].size <= ranges[i + 1].offset);
+
+ /* Get the offsets of the first and last bytes of the read. */
+ const u64 first_offset = ranges[0].offset;
+ const u64 last_offset = ranges[num_ranges - 1].offset + ranges[num_ranges - 1].size - 1;
+
+ /* Get the file descriptor for the WIM. */
+ struct filedes * const in_fd = &rspec->wim->in_fd;
+
+ /* Determine if we're reading a pipable resource from a pipe or not. */
+ const bool is_pipe_read = !filedes_is_seekable(in_fd);
+
+ /* Determine if the chunk table is in an altenate format. */
+ const bool alt_chunk_table = (rspec->flags & WIM_RESHDR_FLAG_CONCAT) && !is_pipe_read;
+
+ /* Get the maximum size of uncompressed chunks in this resource, which
+ * we require be a power of 2. */
+ u32 chunk_size;
+ u64 cur_read_offset = rspec->offset_in_wim;
+ if (alt_chunk_table) {
+ /* Alternate chunk table format. */
+ struct alt_chunk_table_header_disk hdr;
- /* Set the implicit offset of the first chunk if it is included in the
- * needed chunks.
- *
- * Note: M$'s documentation includes a picture that shows the first
- * chunk starting right after the chunk entry table, labeled as offset
- * 0x10. However, in the actual file format, the offset is measured
- * from the end of the chunk entry table, so the first chunk has an
- * offset of 0. */
- if (start_chunk == 0)
- chunk_offsets[0] = 0;
-
- /* According to M$'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. */
-
- /* 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;
-
- /* 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;
-
- /* Number of bytes we need to read from the chunk table. */
- size_t size = num_needed_chunk_entries * chunk_entry_size;
-
- /* Read the raw data into the end of the chunk_offsets array to
- * avoid allocating another array. */
- void *chunk_tab_buf = (void*)&chunk_offsets[num_needed_chunks] - size;
-
- 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. */
-
- u64 *chunk_tab_p = chunk_offsets;
- 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++ = le32_to_cpu(*entries++);
+ ret = full_pread(in_fd, &hdr, sizeof(hdr), cur_read_offset);
+ if (ret)
+ goto read_error;
+ cur_read_offset += sizeof(hdr);
+
+ chunk_size = le32_to_cpu(hdr.chunk_size);
+
+ if (!is_power_of_2(chunk_size)) {
+ ERROR("Invalid compressed resource: "
+ "expected power-of-2 chunk size (got %u)", chunk_size);
+ ret = WIMLIB_ERR_INVALID_CHUNK_SIZE;
+ goto out_free_memory;
+ }
} else {
- u64 *entries = (u64*)chunk_tab_buf;
- while (num_needed_chunk_entries--)
- *chunk_tab_p++ = le64_to_cpu(*entries++);
+ chunk_size = rspec->cchunk_size;
}
+ const u32 chunk_order = bsr32(chunk_size);
+
+ /* Calculate the total number of chunks the resource is divided into. */
+ const u64 num_chunks = (rspec->uncompressed_size + chunk_size - 1) >> chunk_order;
+
+ /* Calculate the 0-based indices of the first and last chunks containing
+ * data that needs to be passed to the callback. */
+ const u64 first_needed_chunk = first_offset >> chunk_order;
+ const u64 last_needed_chunk = last_offset >> chunk_order;
+
+ /* Calculate the 0-based index of the first chunk that actually needs to
+ * be read. This is normally first_needed_chunk, but for pipe reads we
+ * must always start from the 0th chunk. */
+ const u64 read_start_chunk = (is_pipe_read ? 0 : first_needed_chunk);
+
+ /* Calculate the number of chunk offsets that are needed for the chunks
+ * being read. */
+ const u64 num_needed_chunk_offsets =
+ last_needed_chunk - read_start_chunk + 1 +
+ (last_needed_chunk < num_chunks - 1);
+
+ /* Calculate the number of entries in the chunk table. Normally, it's
+ * one less than the number of chunks, since the first chunk has no
+ * entry. But in the alternate chunk table format, the chunk entries
+ * contain chunk sizes, not offsets, and there is one per chunk. */
+ const u64 num_chunk_entries = (alt_chunk_table ? num_chunks : num_chunks - 1);
+
+ /* Set the size of each chunk table entry based on the resource's
+ * uncompressed size. XXX: Does the alternate chunk table really
+ * always have 4-byte entries? */
+ const u64 chunk_entry_size =
+ (rspec->uncompressed_size > (1ULL << 32) && !alt_chunk_table)
+ ? 8 : 4;
+
+ /* Calculate the size of the chunk table in bytes. */
+ const u64 chunk_table_size = num_chunk_entries * chunk_entry_size;
+
+ /* Includes header */
+ const u64 chunk_table_full_size =
+ (alt_chunk_table) ? chunk_table_size + sizeof(struct alt_chunk_table_header_disk)
+ : chunk_table_size;
+
+ if (!is_pipe_read) {
+ /* Read the needed chunk table entries into memory and use them
+ * to initialize the chunk_offsets array. */
+
+ u64 first_chunk_entry_to_read;
+ u64 last_chunk_entry_to_read;
+
+ if (alt_chunk_table) {
+ /* The alternate chunk table contains chunk sizes, not
+ * offsets, so we always must read all preceding entries
+ * in order to determine offsets. */
+ first_chunk_entry_to_read = 0;
+ last_chunk_entry_to_read = last_needed_chunk;
+ } else {
+ /* Here we must account for the fact that the first
+ * chunk has no explicit chunk table entry. */
- /* Done with the chunk table now. We must now seek to the first chunk
- * that is needed for the read. */
+ if (read_start_chunk == 0)
+ first_chunk_entry_to_read = 0;
+ else
+ first_chunk_entry_to_read = read_start_chunk - 1;
- u64 cur_read_offset = resource_offset + chunk_table_size + chunk_offsets[0];
+ if (last_needed_chunk == 0)
+ last_chunk_entry_to_read = 0;
+ else
+ last_chunk_entry_to_read = last_needed_chunk - 1;
- /* Pointer to current position in the output buffer for uncompressed
- * 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
- * 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. */
- void *compressed_buf = alloca(WIM_CHUNK_SIZE - 1);
-
- /* Decompress all the chunks. */
- for (u64 i = start_chunk; i <= end_chunk; i++) {
-
- /* Calculate the sizes of the compressed chunk and of the
- * 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] -
- chunk_offsets[i - start_chunk];
- uncompressed_chunk_size = WIM_CHUNK_SIZE;
+ if (last_needed_chunk < num_chunks - 1)
+ last_chunk_entry_to_read++;
+ }
+
+ const u64 num_chunk_entries_to_read =
+ last_chunk_entry_to_read - first_chunk_entry_to_read + 1;
+
+ const u64 chunk_offsets_alloc_size =
+ max(num_chunk_entries_to_read,
+ num_needed_chunk_offsets) * sizeof(chunk_offsets[0]);
+
+ if ((size_t)chunk_offsets_alloc_size != chunk_offsets_alloc_size)
+ goto oom;
+
+ if (chunk_offsets_alloc_size <= STACK_MAX) {
+ chunk_offsets = alloca(chunk_offsets_alloc_size);
+ } else {
+ chunk_offsets = MALLOC(chunk_offsets_alloc_size);
+ if (chunk_offsets == NULL)
+ goto oom;
+ chunk_offsets_malloced = true;
+ }
+
+ const size_t chunk_table_size_to_read =
+ num_chunk_entries_to_read * chunk_entry_size;
+
+ const u64 file_offset_of_needed_chunk_entries =
+ cur_read_offset
+ + (first_chunk_entry_to_read * chunk_entry_size)
+ + (rspec->is_pipable ? (rspec->size_in_wim - chunk_table_size) : 0);
+
+ void * const chunk_table_data =
+ (u8*)chunk_offsets +
+ chunk_offsets_alloc_size -
+ chunk_table_size_to_read;
+
+ ret = full_pread(in_fd, chunk_table_data, chunk_table_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. We break aliasing rules here to avoid having
+ * to allocate yet another array. */
+ typedef le64 __attribute__((may_alias)) aliased_le64_t;
+ typedef le32 __attribute__((may_alias)) aliased_le32_t;
+ u64 * chunk_offsets_p = chunk_offsets;
+
+ if (alt_chunk_table) {
+ u64 cur_offset = 0;
+ aliased_le32_t *raw_entries = chunk_table_data;
+
+ for (size_t i = 0; i < num_chunk_entries_to_read; i++) {
+ u32 entry = le32_to_cpu(raw_entries[i]);
+ if (i >= read_start_chunk)
+ *chunk_offsets_p++ = cur_offset;
+ cur_offset += entry;
+ }
} 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 -
- chunk_table_size -
- chunk_offsets[i - start_chunk];
-
- 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)
- uncompressed_chunk_size = WIM_CHUNK_SIZE;
+ if (read_start_chunk == 0)
+ *chunk_offsets_p++ = 0;
+
+ if (chunk_entry_size == 4) {
+ aliased_le32_t *raw_entries = chunk_table_data;
+ for (size_t i = 0; i < num_chunk_entries_to_read; i++)
+ *chunk_offsets_p++ = le32_to_cpu(raw_entries[i]);
+ } else {
+ aliased_le64_t *raw_entries = chunk_table_data;
+ for (size_t i = 0; i < num_chunk_entries_to_read; i++)
+ *chunk_offsets_p++ = le64_to_cpu(raw_entries[i]);
+ }
}
- /* Figure out how much of this chunk we actually need to read */
- u64 start_offset;
- if (i == start_chunk)
- start_offset = start_chunk_offset;
+ /* Set offset to beginning of first chunk to read. */
+ cur_read_offset += chunk_offsets[0];
+ if (rspec->is_pipable)
+ cur_read_offset += read_start_chunk * sizeof(struct pwm_chunk_hdr);
else
- start_offset = 0;
- u64 end_offset;
- if (i == end_chunk)
- end_offset = end_chunk_offset;
+ cur_read_offset += chunk_table_size;
+ }
+
+ /* Allocate buffer for holding the uncompressed data of each chunk. */
+ if (chunk_size <= STACK_MAX) {
+ ubuf = alloca(chunk_size);
+ } else {
+ ubuf = MALLOC(chunk_size);
+ if (ubuf == NULL)
+ goto oom;
+ ubuf_malloced = true;
+ }
+
+ /* Unless the raw compressed data was requested, allocate a temporary
+ * buffer for reading compressed chunks, each of which can be at most
+ * @chunk_size - 1 bytes. This excludes compressed chunks that are a
+ * full @chunk_size bytes, which are actually stored uncompressed. */
+ if (!raw_chunks_mode) {
+ if (chunk_size - 1 <= STACK_MAX) {
+ cbuf = alloca(chunk_size - 1);
+ } else {
+ cbuf = MALLOC(chunk_size - 1);
+ if (cbuf == NULL)
+ goto oom;
+ cbuf_malloced = true;
+ }
+ }
+
+ /* Read and process each needed chunk. */
+ const struct data_range *cur_range = ranges;
+ const struct data_range * const end_range = &ranges[num_ranges];
+ u64 cur_range_pos = cur_range->offset;
+ u64 cur_range_end = cur_range->offset + cur_range->size;
+
+ for (u64 i = read_start_chunk; i <= last_needed_chunk; i++) {
+
+ /* Calculate uncompressed size of next chunk. */
+ u32 chunk_usize;
+ if ((i == num_chunks - 1) && (rspec->uncompressed_size & (chunk_size - 1)))
+ chunk_usize = (rspec->uncompressed_size & (chunk_size - 1));
else
- end_offset = WIM_CHUNK_SIZE - 1;
-
- 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) {
- /* 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)
- {
+ chunk_usize = chunk_size;
+
+ /* Calculate compressed size of next chunk. */
+ u32 chunk_csize;
+ if (is_pipe_read) {
+ struct pwm_chunk_hdr chunk_hdr;
+
+ ret = full_pread(in_fd, &chunk_hdr,
+ sizeof(chunk_hdr), cur_read_offset);
+ if (ret)
goto read_error;
- }
+ chunk_csize = le32_to_cpu(chunk_hdr.compressed_size);
} else {
- /* Compressed chunk */
+ if (i == num_chunks - 1) {
+ chunk_csize = rspec->size_in_wim -
+ chunk_table_full_size -
+ chunk_offsets[i - read_start_chunk];
+ if (rspec->is_pipable)
+ chunk_csize -= num_chunks * sizeof(struct pwm_chunk_hdr);
+ } else {
+ chunk_csize = chunk_offsets[i + 1 - read_start_chunk] -
+ chunk_offsets[i - read_start_chunk];
+ }
+ }
+ if (chunk_csize == 0 || chunk_csize > chunk_usize) {
+ ERROR("Invalid chunk size in compressed resource!");
+ errno = EINVAL;
+ ret = WIMLIB_ERR_DECOMPRESSION;
+ goto out_free_memory;
+ }
+ if (rspec->is_pipable)
+ cur_read_offset += sizeof(struct pwm_chunk_hdr);
- /* Read the compressed data into compressed_buf. */
- if (full_pread(in_fd,
- compressed_buf,
- compressed_chunk_size,
- cur_read_offset) != compressed_chunk_size)
- {
- goto read_error;
+ /* Uncompressed offsets */
+ const u64 chunk_start_offset = i << chunk_order;
+ const u64 chunk_end_offset = chunk_start_offset + chunk_usize;
+
+ if (chunk_end_offset <= cur_range_pos) {
+
+ /* The next range does not require data in this chunk,
+ * so skip it. */
+
+ cur_read_offset += chunk_csize;
+ if (is_pipe_read) {
+ u8 dummy;
+
+ ret = full_pread(in_fd, &dummy, 1, cur_read_offset - 1);
+ if (ret)
+ goto read_error;
}
+ } else {
- /* 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];
+ /* Read the chunk and feed data to the callback
+ * function. */
+ u8 *cb_buf;
- ret = decompress(compressed_buf,
- compressed_chunk_size,
- uncompressed_buf,
- uncompressed_chunk_size);
+ ret = full_pread(in_fd,
+ cbuf,
+ chunk_csize,
+ cur_read_offset);
+ if (ret)
+ goto read_error;
+
+ if (chunk_csize != chunk_usize && !raw_chunks_mode) {
+ ret = decompress(cbuf,
+ chunk_csize,
+ ubuf,
+ chunk_usize,
+ rspec->ctype,
+ chunk_size);
if (ret) {
+ ERROR("Failed to decompress data!");
ret = WIMLIB_ERR_DECOMPRESSION;
- goto out;
+ errno = EINVAL;
+ goto out_free_memory;
}
- memcpy(out_p, uncompressed_buf + start_offset,
- partial_chunk_size);
+ cb_buf = ubuf;
} else {
- ret = decompress(compressed_buf,
- compressed_chunk_size,
- out_p,
- uncompressed_chunk_size);
- if (ret) {
- ret = WIMLIB_ERR_DECOMPRESSION;
- goto out;
- }
+ cb_buf = cbuf;
}
+ cur_read_offset += chunk_csize;
+
+ /* At least one range requires data in this chunk.
+ * However, the data fed to the callback function must
+ * not overlap range boundaries. */
+ do {
+ size_t start, end, size;
+
+ start = cur_range_pos - chunk_start_offset;
+ end = min(cur_range_end, chunk_end_offset) - chunk_start_offset;
+ size = end - start;
+
+ if (raw_chunks_mode)
+ ret = (*cb)(&cb_buf[0], chunk_csize, cb_ctx);
+ else
+ ret = (*cb)(&cb_buf[start], size, cb_ctx);
+
+ if (ret)
+ goto out_free_memory;
+
+ cur_range_pos += size;
+ if (cur_range_pos == cur_range_end) {
+ if (++cur_range == end_range) {
+ cur_range_pos = ~0ULL;
+ } else {
+ cur_range_pos = cur_range->offset;
+ cur_range_end = cur_range->offset + cur_range->size;
+ }
+ }
+ } while (cur_range_pos < chunk_end_offset);
}
- 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;
}
+ if (is_pipe_read
+ && last_offset == rspec->uncompressed_size - 1
+ && chunk_table_size)
+ {
+ u8 dummy;
+ /* Skip chunk table at end of pipable resource. */
+
+ cur_read_offset += chunk_table_size;
+ ret = full_pread(in_fd, &dummy, 1, cur_read_offset - 1);
+ if (ret)
+ goto read_error;
+ }
ret = 0;
-out:
+out_free_memory:
+ errno_save = errno;
if (chunk_offsets_malloced)
FREE(chunk_offsets);
+ if (ubuf_malloced)
+ FREE(ubuf);
+ if (cbuf_malloced)
+ FREE(cbuf);
+ errno = errno_save;
return ret;
+oom:
+ ERROR("Not enough memory available to read size=%"PRIu64" bytes "
+ "from compressed resource!", last_offset - first_offset + 1);
+ errno = ENOMEM;
+ ret = WIMLIB_ERR_NOMEM;
+ goto out_free_memory;
+
read_error:
- ERROR_WITH_ERRNO("Error reading compressed file resource");
- ret = WIMLIB_ERR_READ;
- goto out;
+ ERROR_WITH_ERRNO("Error reading compressed file resource!");
+ goto out_free_memory;
}
-/* 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 void *
-get_resource_entry(const void *p, struct resource_entry *entry)
+/* Read raw data from a file descriptor at the specified offset. */
+static int
+read_raw_file_data(struct filedes *in_fd, u64 size, consume_data_callback_t cb,
+ u32 cb_chunk_size, void *ctx_or_buf, u64 offset)
{
- u64 size;
- u8 flags;
-
- p = get_u56(p, &size);
- p = get_u8(p, &flags);
- entry->size = size;
- entry->flags = flags;
-
- /* 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... */
- p = get_u64(p, &entry->offset);
- if (entry->offset & 0xc000000000000000ULL) {
- WARNING("Truncating offset in resource entry");
- entry->offset &= 0x3fffffffffffffffULL;
- }
- p = get_u64(p, &entry->original_size);
- if (entry->original_size & 0xc000000000000000ULL) {
- WARNING("Truncating original_size in resource entry");
- entry->original_size &= 0x3fffffffffffffffULL;
+ int ret;
+ u8 *tmp_buf;
+ bool tmp_buf_malloced = false;
+
+ if (cb) {
+ /* Send data to callback function in chunks. */
+ if (cb_chunk_size <= STACK_MAX) {
+ tmp_buf = alloca(cb_chunk_size);
+ } else {
+ tmp_buf = MALLOC(cb_chunk_size);
+ if (tmp_buf == NULL) {
+ ret = WIMLIB_ERR_NOMEM;
+ goto out;
+ }
+ tmp_buf_malloced = true;
+ }
+
+ while (size) {
+ size_t bytes_to_read = min(cb_chunk_size, size);
+ ret = full_pread(in_fd, tmp_buf, bytes_to_read,
+ offset);
+ if (ret)
+ goto read_error;
+ ret = cb(tmp_buf, bytes_to_read, ctx_or_buf);
+ if (ret)
+ goto out;
+ size -= bytes_to_read;
+ offset += bytes_to_read;
+ }
+ } else {
+ /* Read data directly into buffer. */
+ ret = full_pread(in_fd, ctx_or_buf, size, offset);
+ if (ret)
+ goto read_error;
}
- return p;
+ ret = 0;
+ goto out;
+
+read_error:
+ ERROR_WITH_ERRNO("Read error");
+out:
+ if (tmp_buf_malloced)
+ FREE(tmp_buf);
+ return ret;
}
-/* 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. */
-void *
-put_resource_entry(void *p, const struct resource_entry *entry)
+static int
+bufferer_cb(const void *chunk, size_t size, void *_ctx)
{
- 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;
+ u8 **buf_p = _ctx;
+
+ *buf_p = mempcpy(*buf_p, chunk, size);
+ return 0;
}
+struct rechunker_context {
+ u8 *buffer;
+ u32 buffer_filled;
+ u32 cb_chunk_size;
+
+ const struct data_range *ranges;
+ size_t num_ranges;
+ size_t cur_range;
+ u64 range_bytes_remaining;
+
+ consume_data_callback_t cb;
+ void *cb_ctx;
+};
+
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)
+rechunker_cb(const void *chunk, size_t size, void *_ctx)
{
- WIMStruct *wim;
- int in_fd;
+ struct rechunker_context *ctx = _ctx;
+ const u8 *chunkptr = chunk;
+ size_t bytes_to_copy;
int ret;
- wimlib_assert(lte->resource_location == RESOURCE_IN_WIM);
+ wimlib_assert(ctx->cur_range != ctx->num_ranges);
+
+ while (size) {
+ bytes_to_copy = size;
+
+ if (bytes_to_copy > ctx->cb_chunk_size - ctx->buffer_filled)
+ bytes_to_copy = ctx->cb_chunk_size - ctx->buffer_filled;
+
+ if (bytes_to_copy > ctx->range_bytes_remaining - ctx->buffer_filled)
+ bytes_to_copy = ctx->range_bytes_remaining - ctx->buffer_filled;
+
+ memcpy(&ctx->buffer[ctx->buffer_filled], chunkptr, bytes_to_copy);
+
+ ctx->buffer_filled += bytes_to_copy;
+ chunkptr += bytes_to_copy;
+ size -= bytes_to_copy;
+ ctx->range_bytes_remaining -= bytes_to_copy;
- wim = lte->wim;
- in_fd = wim->in_fd;
+ if (ctx->buffer_filled == ctx->cb_chunk_size ||
+ ctx->range_bytes_remaining == 0)
+ {
+ ret = (*ctx->cb)(ctx->buffer, ctx->buffer_filled, ctx->cb_ctx);
+ if (ret)
+ return ret;
+ ctx->buffer_filled = 0;
+
+ if (ctx->range_bytes_remaining == 0 &&
+ ++ctx->cur_range != ctx->num_ranges)
+ ctx->range_bytes_remaining = ctx->ranges[ctx->cur_range].size;
+ }
+ }
+ return 0;
+}
+
+/*
+ * read_partial_wim_resource()-
+ *
+ * Read a range of data from an uncompressed or compressed resource in a WIM
+ * file. Data is written into a buffer or fed into a callback function, as
+ * documented in read_stream_prefix().
+ *
+ * By default, this function provides the uncompressed data of the resource, and
+ * @size and @offset and interpreted relative to the uncompressed contents of
+ * the resource. This behavior can be modified by either of the following
+ * flags:
+ *
+ * WIMLIB_READ_RESOURCE_FLAG_RAW_FULL:
+ * Read @size bytes at @offset of the raw contents of the compressed
+ * resource. In the case of pipable resources, this excludes the stream
+ * header. Exclusive with WIMLIB_READ_RESOURCE_FLAG_RAW_CHUNKS.
+ *
+ * WIMLIB_READ_RESOURCE_FLAG_RAW_CHUNKS:
+ * Read the raw compressed chunks of the compressed resource. @size must
+ * be the full uncompressed size, @offset must be 0, and @cb_chunk_size
+ * must be the resource chunk size.
+ *
+ * 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)
+ *
+ * or other error code returned by the @cb function.
+ */
+int
+read_partial_wim_resource(const struct wim_lookup_table_entry *lte,
+ u64 size, consume_data_callback_t cb,
+ u32 cb_chunk_size, void *ctx_or_buf,
+ int flags, u64 offset)
+{
+ const struct wim_resource_spec *rspec;
+ struct filedes *in_fd;
- if (lte->resource_entry.flags & WIM_RESHDR_FLAG_COMPRESSED &&
- !(flags & WIMLIB_RESOURCE_FLAG_RAW))
+ /* Verify parameters. */
+ wimlib_assert(lte->resource_location == RESOURCE_IN_WIM);
+ rspec = lte->rspec;
+ in_fd = &rspec->wim->in_fd;
+ if (cb)
+ wimlib_assert(is_power_of_2(cb_chunk_size));
+ if (flags & WIMLIB_READ_RESOURCE_FLAG_RAW_CHUNKS) {
+ /* Raw chunks mode is subject to the restrictions noted. */
+ wimlib_assert(!lte_is_partial(lte));
+ wimlib_assert(!(flags & WIMLIB_READ_RESOURCE_FLAG_RAW_FULL));
+ wimlib_assert(cb_chunk_size == rspec->cchunk_size);
+ wimlib_assert(size == lte->size);
+ wimlib_assert(offset == 0);
+ } else if (flags & WIMLIB_READ_RESOURCE_FLAG_RAW_FULL) {
+ /* Raw full mode: read must not overrun end of store size. */
+ wimlib_assert(!lte_is_partial(lte));
+ wimlib_assert(offset + size >= size &&
+ offset + size <= rspec->size_in_wim);
+ } else {
+ /* Normal mode: read must not overrun end of original size. */
+ wimlib_assert(offset + size >= size &&
+ offset + size <= lte->size);
+ }
+
+ DEBUG("Reading WIM resource: %"PRIu64" @ +%"PRIu64"[+%"PRIu64"] "
+ "from %"PRIu64"(%"PRIu64") @ +%"PRIu64" "
+ "(readflags 0x%08x, resflags 0x%02x%s)",
+ size, offset, lte->offset_in_res,
+ rspec->size_in_wim,
+ rspec->uncompressed_size,
+ rspec->offset_in_wim,
+ flags, lte->flags,
+ (rspec->is_pipable ? ", pipable" : ""));
+
+ if ((flags & WIMLIB_READ_RESOURCE_FLAG_RAW_FULL) ||
+ rspec->ctype == WIMLIB_COMPRESSION_TYPE_NONE)
{
- 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);
+ return read_raw_file_data(in_fd,
+ size,
+ cb,
+ cb_chunk_size,
+ ctx_or_buf,
+ rspec->offset_in_wim + lte->offset_in_res + offset);
} 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;
- }
+ bool raw_chunks;
+ struct data_range range;
+ consume_data_callback_t internal_cb;
+ void *internal_cb_ctx;
+ u8 *buf;
+ bool rechunker_buf_malloced = false;
+ struct rechunker_context *rechunker_ctx;
+ int ret;
+
+ if (size == 0)
+ return 0;
+
+ range.offset = lte->offset_in_res + offset;
+ range.size = size;
+ raw_chunks = !!(flags & WIMLIB_READ_RESOURCE_FLAG_RAW_CHUNKS);
+
+ if (cb != NULL &&
+ cb_chunk_size == rspec->cchunk_size &&
+ !(rspec->flags & WIM_RESHDR_FLAG_CONCAT))
+ {
+ internal_cb = cb;
+ internal_cb_ctx = ctx_or_buf;
+ } else if (cb == NULL) {
+ buf = ctx_or_buf;
+ internal_cb = bufferer_cb;
+ internal_cb_ctx = &buf;
} else {
- /* Send data directly to a buffer */
- if (full_pread(in_fd, ctx_or_buf, size, offset) != size)
- goto read_error;
+ rechunker_ctx = alloca(sizeof(struct rechunker_context));
+
+ if (cb_chunk_size <= STACK_MAX) {
+ rechunker_ctx->buffer = alloca(cb_chunk_size);
+ } else {
+ rechunker_ctx->buffer = MALLOC(cb_chunk_size);
+ if (rechunker_ctx->buffer == NULL)
+ return WIMLIB_ERR_NOMEM;
+ rechunker_buf_malloced = true;
+ }
+ rechunker_ctx->buffer_filled = 0;
+ rechunker_ctx->cb_chunk_size = cb_chunk_size;
+
+ rechunker_ctx->ranges = ⦥
+ rechunker_ctx->num_ranges = 1;
+ rechunker_ctx->cur_range = 0;
+ rechunker_ctx->range_bytes_remaining = range.size;
+
+ rechunker_ctx->cb = cb;
+ rechunker_ctx->cb_ctx = ctx_or_buf;
+
+ internal_cb = rechunker_cb;
+ internal_cb_ctx = rechunker_ctx;
}
- ret = 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;
+
+ ret = read_compressed_wim_resource(rspec, &range, 1,
+ internal_cb, internal_cb_ctx,
+ raw_chunks);
+ if (rechunker_buf_malloced)
+ FREE(rechunker_ctx->buffer);
+
+ return ret;
}
- return ret;
}
-
int
-read_partial_wim_resource_into_buf(const struct wim_lookup_table_entry *lte,
- size_t size, u64 offset, void *buf)
+read_partial_wim_stream_into_buf(const struct wim_lookup_table_entry *lte,
+ size_t size, u64 offset, void *buf)
{
- return read_partial_wim_resource(lte, size, NULL, buf, 0, offset);
+ return read_partial_wim_resource(lte, size, NULL, 0, buf, 0, offset);
}
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)
+read_wim_stream_prefix(const struct wim_lookup_table_entry *lte, u64 size,
+ consume_data_callback_t cb, u32 cb_chunk_size,
+ void *ctx_or_buf, int flags)
{
- return read_partial_wim_resource(lte, size, cb, ctx_or_buf, flags, 0);
+ return read_partial_wim_resource(lte, size, cb, cb_chunk_size,
+ ctx_or_buf, flags, 0);
}
-
#ifndef __WIN32__
+/* This function handles reading stream data that is located in an external
+ * file, such as a file that has been added to the WIM image through execution
+ * of a wimlib_add_command.
+ *
+ * This assumes the file can be accessed using the standard POSIX open(),
+ * read(), and close(). On Windows this will not necessarily be the case (since
+ * the file may need FILE_FLAG_BACKUP_SEMANTICS to be opened, or the file may be
+ * encrypted), so Windows uses its own code for its equivalent case.
+ */
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)
+read_file_on_disk_prefix(const struct wim_lookup_table_entry *lte, u64 size,
+ consume_data_callback_t cb, u32 cb_chunk_size,
+ void *ctx_or_buf, int _ignored_flags)
{
- const tchar *filename = lte->file_on_disk;
int ret;
- int fd;
- size_t bytes_read;
+ int raw_fd;
+ struct filedes fd;
+
+ wimlib_assert(size <= lte->size);
+ DEBUG("Reading %"PRIu64" bytes from \"%"TS"\"", size, lte->file_on_disk);
- fd = open(filename, O_RDONLY);
- if (fd < 0) {
- ERROR_WITH_ERRNO("Can't open \"%"TS"\"", filename);
+ raw_fd = open(lte->file_on_disk, O_BINARY | O_RDONLY);
+ if (raw_fd < 0) {
+ ERROR_WITH_ERRNO("Can't open \"%"TS"\"", lte->file_on_disk);
return WIMLIB_ERR_OPEN;
}
- 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;
- }
- ret = 0;
- goto out_close;
-read_error:
- ERROR_WITH_ERRNO("Error reading \"%"TS"\"", filename);
- ret = WIMLIB_ERR_READ;
-out_close:
- close(fd);
+ filedes_init(&fd, raw_fd);
+ ret = read_raw_file_data(&fd, size, cb, cb_chunk_size, ctx_or_buf, 0);
+ filedes_close(&fd);
return ret;
}
#endif /* !__WIN32__ */
+/* This function handles the trivial case of reading stream data that is, in
+ * fact, already located in an in-memory buffer. */
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)
+ u32 cb_chunk_size, void *ctx_or_buf, int _ignored_flags)
{
- const void *inbuf = lte->attached_buffer;
- int ret;
+ wimlib_assert(size <= lte->size);
if (cb) {
- while (size) {
- size_t chunk_size = min(WIM_CHUNK_SIZE, size);
- ret = cb(inbuf, chunk_size, ctx_or_buf);
+ /* Feed the data into the callback function in
+ * appropriately-sized chunks. */
+ int ret;
+ u32 chunk_size;
+
+ for (u64 offset = 0; offset < size; offset += chunk_size) {
+ chunk_size = min(cb_chunk_size, size - offset);
+ ret = cb((const u8*)lte->attached_buffer + offset,
+ chunk_size, ctx_or_buf);
if (ret)
return ret;
- size -= chunk_size;
- inbuf += chunk_size;
}
} else {
- memcpy(ctx_or_buf, inbuf, size);
+ /* Copy the data directly into the specified buffer. */
+ memcpy(ctx_or_buf, lte->attached_buffer, size);
}
return 0;
}
-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);
+typedef int (*read_stream_prefix_handler_t)(const struct wim_lookup_table_entry *lte,
+ u64 size, consume_data_callback_t cb,
+ u32 cb_chunk_size, void *ctx_or_buf,
+ int flags);
/*
- * 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.
+ * read_stream_prefix()-
+ *
+ * Reads the first @size bytes from a generic "stream", which may be located in
+ * any one of several locations, such as in a WIM file (compressed or
+ * uncompressed), in an external file, or directly in an in-memory buffer.
+ *
+ * This function feeds 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 at least @size
+ * bytes).
*
- * 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).
+ * When (@cb != NULL), @cb_chunk_size specifies the maximum size of data chunks
+ * to feed the callback function. @cb_chunk_size must be positive, and if the
+ * stream is in a WIM file, must be a power of 2. All chunks, except possibly
+ * the last one, will be this size. If (@cb == NULL), @cb_chunk_size is
+ * ignored.
*
- * When using a callback function, it is called with chunks up to 32768 bytes in
- * size until the resource is exhausted.
+ * If the stream is located in a WIM file, @flags can be set as documented in
+ * read_partial_wim_resource(). Otherwise @flags are ignored.
*
- * 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.
+ * Returns 0 on success; nonzero on error. A nonzero value will be returned if
+ * the stream data cannot be successfully read (for a number of different
+ * reasons, depending on the stream location), or if a callback function was
+ * specified and it returned nonzero.
*/
int
-read_resource_prefix(const struct wim_lookup_table_entry *lte,
- u64 size, consume_data_callback_t cb, void *ctx_or_buf,
- int flags)
+read_stream_prefix(const struct wim_lookup_table_entry *lte, u64 size,
+ consume_data_callback_t cb, u32 cb_chunk_size,
+ void *ctx_or_buf, int flags)
{
- static const read_resource_prefix_handler_t handlers[] = {
- [RESOURCE_IN_WIM] = read_wim_resource_prefix,
- #ifndef __WIN32__
+ /* This function merely verifies several preconditions, then passes
+ * control to an appropriate function for understanding each possible
+ * stream location. */
+ static const read_stream_prefix_handler_t handlers[] = {
+ [RESOURCE_IN_WIM] = read_wim_stream_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,
[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);
+ wimlib_assert(cb == NULL || cb_chunk_size > 0);
+ return handlers[lte->resource_location](lte, size, cb, cb_chunk_size,
+ ctx_or_buf, flags);
}
+/* Read the full uncompressed data of the specified stream into the specified
+ * buffer, which must have space for at least lte->size bytes. */
int
-read_full_resource_into_buf(const struct wim_lookup_table_entry *lte,
- void *buf)
+read_full_stream_into_buf(const struct wim_lookup_table_entry *lte, void *buf)
{
- return read_resource_prefix(lte, wim_resource_size(lte), NULL, buf, 0);
+ return read_stream_prefix(lte, lte->size, NULL, 0, buf, 0);
+}
+
+/* Read the full uncompressed data of the specified stream. A buffer sufficient
+ * to hold the data is allocated and returned in @buf_ret. */
+int
+read_full_stream_into_alloc_buf(const struct wim_lookup_table_entry *lte,
+ void **buf_ret)
+{
+ int ret;
+ void *buf;
+
+ if ((size_t)lte->size != lte->size) {
+ ERROR("Can't read %"PRIu64" byte stream into "
+ "memory", lte->size);
+ return WIMLIB_ERR_NOMEM;
+ }
+
+ buf = MALLOC(lte->size);
+ if (buf == NULL)
+ return WIMLIB_ERR_NOMEM;
+
+ ret = read_full_stream_into_buf(lte, buf);
+ if (ret) {
+ FREE(buf);
+ return ret;
+ }
+
+ *buf_ret = buf;
+ return 0;
+}
+
+/* Retrieve the full uncompressed data of the specified WIM resource. */
+static int
+wim_resource_spec_to_data(struct wim_resource_spec *rspec, void **buf_ret)
+{
+ int ret;
+ struct wim_lookup_table_entry *lte;
+
+ lte = new_lookup_table_entry();
+ if (lte == NULL)
+ return WIMLIB_ERR_NOMEM;
+
+ lte->unhashed = 1;
+ lte_bind_wim_resource_spec(lte, rspec);
+ lte->flags = rspec->flags;
+ lte->size = rspec->uncompressed_size;
+ lte->offset_in_res = 0;
+
+ ret = read_full_stream_into_alloc_buf(lte, buf_ret);
+
+ lte_unbind_wim_resource_spec(lte);
+ free_lookup_table_entry(lte);
+ return ret;
+}
+
+/* Retrieve the full uncompressed data of the specified WIM resource. */
+int
+wim_reshdr_to_data(const struct wim_reshdr *reshdr, WIMStruct *wim, void **buf_ret)
+{
+ DEBUG("offset_in_wim=%"PRIu64", size_in_wim=%"PRIu64", "
+ "uncompressed_size=%"PRIu64,
+ reshdr->offset_in_wim, reshdr->size_in_wim, reshdr->uncompressed_size);
+
+ struct wim_resource_spec rspec;
+ wim_res_hdr_to_spec(reshdr, wim, &rspec);
+ return wim_resource_spec_to_data(&rspec, buf_ret);
+}
+
+struct read_stream_list_ctx {
+ read_stream_list_begin_stream_t begin_stream;
+ consume_data_callback_t consume_chunk;
+ read_stream_list_end_stream_t end_stream;
+ void *begin_stream_ctx;
+ void *consume_chunk_ctx;
+ void *end_stream_ctx;
+ struct wim_lookup_table_entry *cur_stream;
+ u64 cur_stream_offset;
+ struct wim_lookup_table_entry *final_stream;
+ size_t list_head_offset;
+};
+
+static int
+read_stream_list_wrapper_cb(const void *chunk, size_t size, void *_ctx)
+{
+ struct read_stream_list_ctx *ctx = _ctx;
+ int ret;
+
+ if (ctx->cur_stream_offset == 0) {
+ /* Starting a new stream. */
+ ret = (*ctx->begin_stream)(ctx->cur_stream, ctx->begin_stream_ctx);
+ if (ret)
+ return ret;
+ }
+
+ ret = (*ctx->consume_chunk)(chunk, size, ctx->consume_chunk_ctx);
+ if (ret)
+ return ret;
+
+ ctx->cur_stream_offset += size;
+
+ if (ctx->cur_stream_offset == ctx->cur_stream->size) {
+ /* Finished reading all the data for a stream; advance
+ * to the next one. */
+ ret = (*ctx->end_stream)(ctx->cur_stream, ctx->end_stream_ctx);
+ if (ret)
+ return ret;
+
+ if (ctx->cur_stream == ctx->final_stream)
+ return 0;
+
+ struct list_head *cur = (struct list_head *)
+ ((u8*)ctx->cur_stream + ctx->list_head_offset);
+ struct list_head *next = cur->next;
+
+ ctx->cur_stream = (struct wim_lookup_table_entry *)
+ ((u8*)next - ctx->list_head_offset);
+
+ ctx->cur_stream_offset = 0;
+ }
+ return 0;
+}
+
+/*
+ * Read a list of streams, each of which may be in any supported location (e.g.
+ * in a WIM or in an external file). Unlike read_stream_prefix() or the
+ * functions which call it, this function optimizes the case where multiple
+ * streams are packed into a single compressed WIM resource and reads them all
+ * consecutively, only decompressing the data one time.
+ *
+ * @stream_list
+ * List of streams (represented as `struct wim_lookup_table_entry's) to
+ * read.
+ * @list_head_offset
+ * Offset of the `struct list_head' within each `struct
+ * wim_lookup_table_entry' that makes up the @stream_list.
+ * @begin_stream
+ * Callback for starting to process a stream.
+ * @consume_chunk
+ * Callback for receiving a chunk of stream data.
+ * @end_stream
+ * Callback for finishing the processing of a stream.
+ * @cb_chunk_size
+ * Size of chunks to provide to @consume_chunk. For a given stream, all
+ * the chunks will be this size, except possibly the last which will be the
+ * remainder.
+ * @cb_ctx
+ * Parameter to pass to the callback functions.
+ *
+ * Returns 0 on success; a nonzero error code on failure. Failure can occur due
+ * to an error reading the data or due to an error status being returned by any
+ * of the callback functions.
+ */
+int
+read_stream_list(struct list_head *stream_list,
+ size_t list_head_offset,
+ read_stream_list_begin_stream_t begin_stream,
+ consume_data_callback_t consume_chunk,
+ read_stream_list_end_stream_t end_stream,
+ u32 cb_chunk_size,
+ void *cb_ctx)
+{
+ int ret;
+ struct list_head *cur, *next;
+ struct wim_lookup_table_entry *lte;
+
+ ret = sort_stream_list_by_sequential_order(stream_list, list_head_offset);
+ if (ret)
+ return ret;
+
+ for (cur = stream_list->next, next = cur->next;
+ cur != stream_list;
+ cur = next, next = cur->next)
+ {
+ lte = (struct wim_lookup_table_entry*)((u8*)cur - list_head_offset);
+
+ if (lte_is_partial(lte)) {
+
+ struct wim_lookup_table_entry *lte_next, *lte_last;
+ struct list_head *next2;
+ size_t stream_count;
+
+ /* The next stream is a proper sub-sequence of a WIM
+ * resource. See if there are other streams in the same
+ * resource that need to be read. Since
+ * sort_stream_list_by_sequential_order() sorted the
+ * streams by offset in the WIM, this can be determined
+ * by simply scanning forward in the list. */
+
+ lte_last = lte;
+ stream_count = 1;
+ for (next2 = next;
+ next2 != stream_list
+ && (lte_next = (struct wim_lookup_table_entry*)
+ ((u8*)next2 - list_head_offset),
+ lte_next->resource_location == RESOURCE_IN_WIM
+ && lte_next->rspec == lte->rspec);
+ next2 = next2->next)
+ {
+ lte_last = lte_next;
+ stream_count++;
+ }
+ if (stream_count > 1) {
+ /* Reading multiple streams combined into a
+ * single WIM resource. They are in the stream
+ * list, sorted by offset; @lte specifies the
+ * first stream in the resource that needs to be
+ * read and @lte_last specifies the last stream
+ * in the resource that needs to be read. */
+
+ next = next2;
+
+ struct data_range ranges[stream_count];
+
+ {
+ struct list_head *next3;
+ size_t i;
+ struct wim_lookup_table_entry *lte_cur;
+
+ next3 = cur;
+ for (i = 0; i < stream_count; i++) {
+ lte_cur = (struct wim_lookup_table_entry*)
+ ((u8*)next3 - list_head_offset);
+ ranges[i].offset = lte_cur->offset_in_res;
+ ranges[i].size = lte_cur->size;
+ next3 = next3->next;
+ }
+ }
+
+ struct rechunker_context rechunker_ctx = {
+ .buffer = MALLOC(cb_chunk_size),
+ .buffer_filled = 0,
+ .cb_chunk_size = cb_chunk_size,
+ .ranges = ranges,
+ .num_ranges = stream_count,
+ .cur_range = 0,
+ .range_bytes_remaining = ranges[0].size,
+ .cb = consume_chunk,
+ .cb_ctx = cb_ctx,
+ };
+
+ if (rechunker_ctx.buffer == NULL)
+ return WIMLIB_ERR_NOMEM;
+
+ struct read_stream_list_ctx ctx = {
+ .begin_stream = begin_stream,
+ .begin_stream_ctx = cb_ctx,
+ .consume_chunk = rechunker_cb,
+ .consume_chunk_ctx = &rechunker_ctx,
+ .end_stream = end_stream,
+ .end_stream_ctx = cb_ctx,
+ .cur_stream = lte,
+ .cur_stream_offset = 0,
+ .final_stream = lte_last,
+ .list_head_offset = list_head_offset,
+ };
+
+ ret = read_compressed_wim_resource(lte->rspec,
+ ranges,
+ stream_count,
+ read_stream_list_wrapper_cb,
+ &ctx,
+ false);
+ FREE(rechunker_ctx.buffer);
+ if (ret)
+ return ret;
+ continue;
+ }
+ }
+ ret = (*begin_stream)(lte, cb_ctx);
+ if (ret)
+ return ret;
+
+ ret = read_stream_prefix(lte, lte->size, consume_chunk,
+ cb_chunk_size, cb_ctx, 0);
+ if (ret)
+ return ret;
+
+ ret = (*end_stream)(lte, cb_ctx);
+ if (ret)
+ return ret;
+ }
+ return 0;
}
struct extract_ctx {
};
static int
-extract_chunk_sha1_wrapper(const void *chunk, size_t chunk_size,
- void *_ctx)
+extract_chunk_sha1_wrapper(const void *chunk, size_t chunk_size, void *_ctx)
{
struct extract_ctx *ctx = _ctx;
return ctx->extract_chunk(chunk, chunk_size, ctx->extract_chunk_arg);
}
-/* 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.
+/* Extracts the first @size bytes of a stream to somewhere. In the process, the
+ * SHA1 message digest of the uncompressed stream is checked if the full stream
+ * is being extracted.
*
- * @extract_chunk is a function that is called to extract each chunk of the
- * resource. */
+ * @extract_chunk is a function that will be called to extract each chunk of the
+ * stream. */
int
-extract_wim_resource(const struct wim_lookup_table_entry *lte,
- u64 size,
- consume_data_callback_t extract_chunk,
- void *extract_chunk_arg)
+extract_stream(const struct wim_lookup_table_entry *lte, u64 size,
+ consume_data_callback_t extract_chunk, void *extract_chunk_arg)
{
int ret;
- if (size == wim_resource_size(lte)) {
+ if (size == lte->size) {
/* 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);
+ ret = read_stream_prefix(lte, size,
+ extract_chunk_sha1_wrapper,
+ lte_cchunk_size(lte),
+ &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
+ if (wimlib_print_errors) {
+ ERROR("Invalid SHA1 message digest "
+ "on the following WIM stream:");
+ 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);
+ ret = read_stream_prefix(lte, size, extract_chunk,
+ lte_cchunk_size(lte),
+ extract_chunk_arg, 0);
}
return ret;
}
static int
extract_wim_chunk_to_fd(const void *buf, size_t len, void *_fd_p)
{
- int fd = *(int*)_fd_p;
- ssize_t ret = full_write(fd, buf, len);
- if (ret < len) {
+ struct filedes *fd = _fd_p;
+ int ret = full_write(fd, buf, len);
+ if (ret)
ERROR_WITH_ERRNO("Error writing to file descriptor");
- return WIMLIB_ERR_WRITE;
- } else {
- return 0;
- }
+ return ret;
}
+/* Extract the first @size bytes of the specified stream to the specified file
+ * descriptor. If @size is the full size of the stream, its SHA1 message digest
+ * is also checked. */
int
-extract_wim_resource_to_fd(const struct wim_lookup_table_entry *lte,
- int fd, u64 size)
+extract_stream_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);
+ return extract_stream(lte, size, extract_wim_chunk_to_fd, fd);
}
return 0;
}
-/* Calculate the SHA1 message digest of a stream. */
+/* Calculate the SHA1 message digest of a stream, storing it in @lte->hash. */
int
-sha1_resource(struct wim_lookup_table_entry *lte)
+sha1_stream(struct wim_lookup_table_entry *lte)
{
int ret;
SHA_CTX sha_ctx;
sha1_init(&sha_ctx);
- ret = read_resource_prefix(lte, wim_resource_size(lte),
- sha1_chunk, &sha_ctx, 0);
+ ret = read_stream_prefix(lte, lte->size,
+ sha1_chunk, lte_cchunk_size(lte),
+ &sha_ctx, 0);
if (ret == 0)
sha1_final(lte->hash, &sha_ctx);
+
return ret;
}
-/*
- * 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.
- *
- * The output_resource_entry, out_refcnt, and part_number fields of @lte are
- * updated.
- *
- * (This function is confusing and should be refactored somehow.)
- */
+/* Convert a WIM resource header to a stand-alone resource specification. */
+void
+wim_res_hdr_to_spec(const struct wim_reshdr *reshdr, WIMStruct *wim,
+ struct wim_resource_spec *spec)
+{
+ spec->wim = wim;
+ spec->offset_in_wim = reshdr->offset_in_wim;
+ spec->size_in_wim = reshdr->size_in_wim;
+ spec->uncompressed_size = reshdr->uncompressed_size;
+ INIT_LIST_HEAD(&spec->lte_list);
+ spec->flags = reshdr->flags;
+ spec->is_pipable = wim_is_pipable(wim);
+ if (spec->flags & (WIM_RESHDR_FLAG_COMPRESSED | WIM_RESHDR_FLAG_CONCAT)) {
+ spec->ctype = wim->compression_type;
+ spec->cchunk_size = wim->chunk_size;
+ } else {
+ spec->ctype = WIMLIB_COMPRESSION_TYPE_NONE;
+ spec->cchunk_size = 0;
+ }
+}
+
+/* Convert a stand-alone resource specification to a WIM resource header. */
+void
+wim_res_spec_to_hdr(const struct wim_resource_spec *rspec,
+ struct wim_reshdr *reshdr)
+{
+ reshdr->offset_in_wim = rspec->offset_in_wim;
+ reshdr->size_in_wim = rspec->size_in_wim;
+ reshdr->flags = rspec->flags;
+ reshdr->uncompressed_size = rspec->uncompressed_size;
+}
+
+/* Translates a WIM resource header from the on-disk format into an in-memory
+ * format. */
int
-copy_resource(struct wim_lookup_table_entry *lte, void *wim)
+get_wim_reshdr(const struct wim_reshdr_disk *disk_reshdr,
+ struct wim_reshdr *reshdr)
{
- WIMStruct *w = wim;
- int ret;
+ reshdr->offset_in_wim = le64_to_cpu(disk_reshdr->offset_in_wim);
+ reshdr->size_in_wim = (((u64)disk_reshdr->size_in_wim[0] << 0) |
+ ((u64)disk_reshdr->size_in_wim[1] << 8) |
+ ((u64)disk_reshdr->size_in_wim[2] << 16) |
+ ((u64)disk_reshdr->size_in_wim[3] << 24) |
+ ((u64)disk_reshdr->size_in_wim[4] << 32) |
+ ((u64)disk_reshdr->size_in_wim[5] << 40) |
+ ((u64)disk_reshdr->size_in_wim[6] << 48));
+ reshdr->uncompressed_size = le64_to_cpu(disk_reshdr->uncompressed_size);
+ reshdr->flags = disk_reshdr->flags;
+
+ /* Truncate numbers to 62 bits to avoid possible overflows. */
+ if (reshdr->offset_in_wim & 0xc000000000000000ULL)
+ return WIMLIB_ERR_INVALID_LOOKUP_TABLE_ENTRY;
+
+ if (reshdr->uncompressed_size & 0xc000000000000000ULL)
+ return WIMLIB_ERR_INVALID_LOOKUP_TABLE_ENTRY;
- 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 ret;
+ return 0;
+}
+
+/* Translates a WIM resource header from an in-memory format into the on-disk
+ * format. */
+void
+put_wim_reshdr(const struct wim_reshdr *reshdr,
+ struct wim_reshdr_disk *disk_reshdr)
+{
+ disk_reshdr->size_in_wim[0] = reshdr->size_in_wim >> 0;
+ disk_reshdr->size_in_wim[1] = reshdr->size_in_wim >> 8;
+ disk_reshdr->size_in_wim[2] = reshdr->size_in_wim >> 16;
+ disk_reshdr->size_in_wim[3] = reshdr->size_in_wim >> 24;
+ disk_reshdr->size_in_wim[4] = reshdr->size_in_wim >> 32;
+ disk_reshdr->size_in_wim[5] = reshdr->size_in_wim >> 40;
+ disk_reshdr->size_in_wim[6] = reshdr->size_in_wim >> 48;
+ disk_reshdr->flags = reshdr->flags;
+ disk_reshdr->offset_in_wim = cpu_to_le64(reshdr->offset_in_wim);
+ disk_reshdr->uncompressed_size = cpu_to_le64(reshdr->uncompressed_size);
}