}
}
-/* Read data from a compressed WIM resource. Assumes parameters were already
- * verified by read_partial_wim_resource(). */
+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 u64 size, const consume_data_callback_t cb,
- const u32 cb_chunk_size, void * const ctx_or_buf,
- const int flags, const u64 offset)
+ 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;
- const u32 orig_chunk_size = rspec->cchunk_size;
- const u32 orig_chunk_order = bsr32(orig_chunk_size);
+ 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);
- wimlib_assert(is_power_of_2(orig_chunk_size));
+ /* 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;
- /* Handle the trivial case. */
- if (size == 0)
- return 0;
+ /* Get the file descriptor for the WIM. */
+ struct filedes * const in_fd = &rspec->wim->in_fd;
- if (rspec->ctype == WIMLIB_COMPRESSION_TYPE_LZMS) {
- /* TODO */
+ /* Determine if we're reading a pipable resource from a pipe or not. */
+ const bool is_pipe_read = !filedes_is_seekable(in_fd);
- unsigned clen = rspec->size_in_wim;
- unsigned ulen = rspec->uncompressed_size;
- unsigned lzms_offset;
+ /* Determine if the chunk table is in an altenate format. */
+ const bool alt_chunk_table = (rspec->flags & WIM_RESHDR_FLAG_CONCAT) && !is_pipe_read;
- fprintf(stderr, "clen=%u, ulen=%u, offset=%lu\n", clen, ulen,
- rspec->offset_in_wim);
+ /* 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;
- u8 *cbuf = MALLOC(clen);
- u8 *ubuf = MALLOC(ulen);
+ 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);
- ret = full_pread(&rspec->wim->in_fd,
- cbuf, clen, rspec->offset_in_wim);
- if (ret) {
- ERROR_WITH_ERRNO("Can't read compressed data");
- goto out_free_bufs;
+ 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 {
+ chunk_size = rspec->cchunk_size;
+ }
+ const u32 chunk_order = bsr32(chunk_size);
- if (clen <= rspec->cchunk_size)
- lzms_offset = 0;
- else
- lzms_offset = 20;
+ /* Calculate the total number of chunks the resource is divided into. */
+ const u64 num_chunks = (rspec->uncompressed_size + chunk_size - 1) >> chunk_order;
- ret = wimlib_lzms_decompress(cbuf + lzms_offset,
- clen - lzms_offset,
- ubuf, ulen);
- if (ret) {
- ERROR("LZMS decompression error.");
- errno = EINVAL;
- ret = WIMLIB_ERR_DECOMPRESSION;
- goto out_free_bufs;
- }
- if (cb) {
- u32 chunk_size;
- for (u64 i = offset; i < offset + size; i += chunk_size) {
- chunk_size = min(offset + size - i, cb_chunk_size);
- ret = cb(&ubuf[i], chunk_size, ctx_or_buf);
- if (ret)
- goto out_free_bufs;
- }
- } else {
- memcpy(ctx_or_buf, &ubuf[offset], size);
- }
- ret = 0;
- out_free_bufs:
- FREE(ubuf);
- FREE(cbuf);
- return ret;
- }
+ /* 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;
- u64 *chunk_offsets = NULL;
- u8 *out_buf = NULL;
- u8 *tmp_buf = NULL;
- void *compressed_buf = NULL;
- bool chunk_offsets_malloced = false;
- bool out_buf_malloced = false;
- bool tmp_buf_malloced = false;
- bool compressed_buf_malloced = false;
+ /* 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);
- /* Get the file descriptor for the WIM. */
- struct filedes * const in_fd = &rspec->wim->in_fd;
+ /* 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);
- /* Determine if we're reading a pipable resource from a pipe or not. */
- const bool is_pipe_read = !filedes_is_seekable(in_fd);
+ /* 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);
- /* Calculate the number of chunks the resource is divided into. */
- const u64 num_chunks = (rspec->uncompressed_size + orig_chunk_size - 1) >> orig_chunk_order;
+ /* 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 0-based index of the chunk at which the read starts.
- */
- const u64 start_chunk = offset >> orig_chunk_order;
+ /* Calculate the size of the chunk table in bytes. */
+ const u64 chunk_table_size = num_chunk_entries * chunk_entry_size;
- /* For pipe reads, we always must start from the 0th chunk. */
- const u64 actual_start_chunk = (is_pipe_read ? 0 : start_chunk);
+ /* Includes header */
+ const u64 chunk_table_full_size =
+ (alt_chunk_table) ? chunk_table_size + sizeof(struct alt_chunk_table_header_disk)
+ : chunk_table_size;
- /* Calculate the offset, within the start chunk, of the first byte of
- * the read. */
- const u32 start_offset_in_chunk = offset & (orig_chunk_size - 1);
+ 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. */
- /* Calculate the index of the chunk that contains the last byte of the
- * read. */
- const u64 end_chunk = (offset + size - 1) >> orig_chunk_order;
+ if (read_start_chunk == 0)
+ first_chunk_entry_to_read = 0;
+ else
+ first_chunk_entry_to_read = read_start_chunk - 1;
- /* Calculate the offset, within the end chunk, of the last byte of the
- * read. */
- const u32 end_offset_in_chunk = (offset + size - 1) & (orig_chunk_size - 1);
+ if (last_needed_chunk == 0)
+ last_chunk_entry_to_read = 0;
+ else
+ last_chunk_entry_to_read = last_needed_chunk - 1;
- /* 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. */
- const u64 num_chunk_entries = num_chunks - 1;
+ if (last_needed_chunk < num_chunks - 1)
+ last_chunk_entry_to_read++;
+ }
- /* Set the size of each chunk table entry based on the resource's
- * uncompressed size. */
- const u64 chunk_entry_size = (rspec->uncompressed_size > (1ULL << 32)) ? 8 : 4;
+ const u64 num_chunk_entries_to_read =
+ last_chunk_entry_to_read - first_chunk_entry_to_read + 1;
- /* Calculate the size, in bytes, of the full chunk table. */
- const u64 chunk_table_size = num_chunk_entries * chunk_entry_size;
+ const u64 chunk_offsets_alloc_size =
+ max(num_chunk_entries_to_read,
+ num_needed_chunk_offsets) * sizeof(chunk_offsets[0]);
- /* Current offset to read from. */
- u64 cur_read_offset = rspec->offset_in_wim;
- if (!is_pipe_read) {
- /* Read the chunk table into memory. */
-
- /* 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. */
- const u64 num_alloc_chunk_entries = end_chunk - start_chunk +
- 1 + (end_chunk != num_chunks - 1);
-
- /* 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. */
- if ((size_t)(num_alloc_chunk_entries * sizeof(u64)) !=
- (num_alloc_chunk_entries * sizeof(u64)))
+ if ((size_t)chunk_offsets_alloc_size != chunk_offsets_alloc_size)
goto oom;
- if (num_alloc_chunk_entries <= STACK_MAX / sizeof(u64)) {
- chunk_offsets = alloca(num_alloc_chunk_entries * sizeof(u64));
+ if (chunk_offsets_alloc_size <= STACK_MAX) {
+ chunk_offsets = alloca(chunk_offsets_alloc_size);
} else {
- chunk_offsets = MALLOC(num_alloc_chunk_entries * sizeof(u64));
+ chunk_offsets = MALLOC(chunk_offsets_alloc_size);
if (chunk_offsets == NULL)
goto oom;
chunk_offsets_malloced = true;
}
- /* Set the implicit offset of the first chunk if it's included
- * in the needed chunks. */
- if (start_chunk == 0)
- chunk_offsets[0] = 0;
-
- /* Calculate the index of the first needed entry in the chunk
- * table. */
- const u64 start_table_idx = (start_chunk == 0) ?
- 0 : start_chunk - 1;
-
- /* Calculate the number of entries that need to be read from the
- * chunk table. */
- const 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. */
- const size_t chunk_table_needed_size =
- num_needed_chunk_entries * chunk_entry_size;
-
- /* 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. */
+ const size_t chunk_table_size_to_read =
+ num_chunk_entries_to_read * chunk_entry_size;
+
const u64 file_offset_of_needed_chunk_entries =
- rspec->offset_in_wim
- + (start_table_idx * chunk_entry_size)
+ cur_read_offset
+ + (first_chunk_entry_to_read * chunk_entry_size)
+ (rspec->is_pipable ? (rspec->size_in_wim - chunk_table_size) : 0);
- /* Read the needed chunk table entries into the end of the
- * chunk_offsets buffer. */
- void * const 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,
+ 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. 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 * const chunk_offsets_p = chunk_offsets + (start_chunk == 0);
- u64 i;
+ * 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 {
+ if (read_start_chunk == 0)
+ *chunk_offsets_p++ = 0;
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]);
+ 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 = (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]);
+ 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]);
}
}
/* Set offset to beginning of first chunk to read. */
cur_read_offset += chunk_offsets[0];
if (rspec->is_pipable)
- cur_read_offset += start_chunk * sizeof(struct pwm_chunk_hdr);
+ cur_read_offset += read_start_chunk * sizeof(struct pwm_chunk_hdr);
else
cur_read_offset += chunk_table_size;
}
- /* If using a callback function, allocate a temporary buffer that will
- * hold data being passed to it. If writing directly to a buffer
- * instead, arrange to write data directly into it. */
- size_t out_buf_size;
- u8 *out_buf_end, *out_p;
- if (cb) {
- out_buf_size = max(cb_chunk_size, orig_chunk_size);
- if (out_buf_size <= STACK_MAX) {
- out_buf = alloca(out_buf_size);
- } else {
- out_buf = MALLOC(out_buf_size);
- if (out_buf == NULL)
- goto oom;
- out_buf_malloced = true;
- }
+ /* Allocate buffer for holding the uncompressed data of each chunk. */
+ if (chunk_size <= STACK_MAX) {
+ ubuf = alloca(chunk_size);
} else {
- out_buf_size = size;
- out_buf = ctx_or_buf;
+ ubuf = MALLOC(chunk_size);
+ if (ubuf == NULL)
+ goto oom;
+ ubuf_malloced = true;
}
- out_buf_end = out_buf + out_buf_size;
- out_p = out_buf;
/* Unless the raw compressed data was requested, allocate a temporary
* buffer for reading compressed chunks, each of which can be at most
- * @orig_chunk_size - 1 bytes. This excludes compressed chunks that are
- * a full @orig_chunk_size bytes, which are actually stored
- * uncompressed. */
- if (!(flags & WIMLIB_READ_RESOURCE_FLAG_RAW_CHUNKS)) {
- if (orig_chunk_size - 1 <= STACK_MAX) {
- compressed_buf = alloca(orig_chunk_size - 1);
+ * @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 {
- compressed_buf = MALLOC(orig_chunk_size - 1);
- if (compressed_buf == NULL)
+ cbuf = MALLOC(chunk_size - 1);
+ if (cbuf == NULL)
goto oom;
- compressed_buf_malloced = true;
+ cbuf_malloced = true;
}
}
- /* Allocate yet another temporary buffer, this one for decompressing
- * chunks for which only part of the data is needed. */
- if (start_offset_in_chunk != 0 ||
- (end_offset_in_chunk != orig_chunk_size - 1 &&
- offset + size != rspec->uncompressed_size))
- {
- if (orig_chunk_size <= STACK_MAX) {
- tmp_buf = alloca(orig_chunk_size);
- } else {
- tmp_buf = MALLOC(orig_chunk_size);
- if (tmp_buf == NULL)
- goto oom;
- tmp_buf_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;
- /* 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 = actual_start_chunk; i <= end_chunk; i++) {
+ 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 & (orig_chunk_size - 1)))
- chunk_usize = (rspec->uncompressed_size & (orig_chunk_size - 1));
+ if ((i == num_chunks - 1) && (rspec->uncompressed_size & (chunk_size - 1)))
+ chunk_usize = (rspec->uncompressed_size & (chunk_size - 1));
else
- chunk_usize = orig_chunk_size;
+ chunk_usize = chunk_size;
/* Calculate compressed size of next chunk. */
u32 chunk_csize;
} else {
if (i == num_chunks - 1) {
chunk_csize = rspec->size_in_wim -
- chunk_table_size -
- chunk_offsets[i - start_chunk];
+ 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 - start_chunk] -
- chunk_offsets[i - start_chunk];
+ chunk_csize = chunk_offsets[i + 1 - read_start_chunk] -
+ chunk_offsets[i - read_start_chunk];
}
}
if (chunk_csize == 0 || chunk_csize > chunk_usize) {
if (rspec->is_pipable)
cur_read_offset += sizeof(struct pwm_chunk_hdr);
- if (i >= start_chunk) {
- /* Calculate how much of this chunk needs to be read. */
- u32 chunk_needed_size;
- u32 start_offset = 0;
- u32 end_offset = orig_chunk_size - 1;
-
- if (flags & WIMLIB_READ_RESOURCE_FLAG_RAW_CHUNKS) {
- chunk_needed_size = chunk_csize;
- } else {
- if (i == start_chunk)
- start_offset = start_offset_in_chunk;
+ /* Uncompressed offsets */
+ const u64 chunk_start_offset = i << chunk_order;
+ const u64 chunk_end_offset = chunk_start_offset + chunk_usize;
- if (i == end_chunk)
- end_offset = end_offset_in_chunk;
+ if (chunk_end_offset <= cur_range_pos) {
- chunk_needed_size = end_offset + 1 - start_offset;
- }
+ /* The next range does not require data in this chunk,
+ * so skip it. */
- if (chunk_csize == chunk_usize ||
- (flags & WIMLIB_READ_RESOURCE_FLAG_RAW_CHUNKS))
- {
- /* Read the raw chunk data. */
+ cur_read_offset += chunk_csize;
+ if (is_pipe_read) {
+ u8 dummy;
- ret = full_pread(in_fd,
- out_p,
- chunk_needed_size,
- cur_read_offset + start_offset);
+ ret = full_pread(in_fd, &dummy, 1, cur_read_offset - 1);
if (ret)
goto read_error;
- } else {
- /* Read and decompress the chunk. */
+ }
+ } else {
- u8 *target;
+ /* Read the chunk and feed data to the callback
+ * function. */
+ u8 *cb_buf;
- ret = full_pread(in_fd,
- compressed_buf,
- chunk_csize,
- cur_read_offset);
- if (ret)
- goto read_error;
-
- if (chunk_needed_size == chunk_usize)
- target = out_p;
- else
- target = tmp_buf;
+ ret = full_pread(in_fd,
+ cbuf,
+ chunk_csize,
+ cur_read_offset);
+ if (ret)
+ goto read_error;
- ret = decompress(compressed_buf,
+ if (chunk_csize != chunk_usize && !raw_chunks_mode) {
+ ret = decompress(cbuf,
chunk_csize,
- target,
+ ubuf,
chunk_usize,
rspec->ctype,
- orig_chunk_size);
+ chunk_size);
if (ret) {
ERROR("Failed to decompress data!");
ret = WIMLIB_ERR_DECOMPRESSION;
errno = EINVAL;
goto out_free_memory;
}
- if (chunk_needed_size != chunk_usize)
- memcpy(out_p, tmp_buf + start_offset,
- chunk_needed_size);
+ cb_buf = ubuf;
+ } else {
+ 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;
- out_p += chunk_needed_size;
-
- if (cb) {
- /* Feed the data to the callback function. */
-
- if (flags & WIMLIB_READ_RESOURCE_FLAG_RAW_CHUNKS) {
- ret = cb(out_buf, out_p - out_buf, ctx_or_buf);
- if (ret)
- goto out_free_memory;
- out_p = out_buf;
- } else if (i == end_chunk || out_p == out_buf_end) {
- size_t bytes_sent;
- const u8 *p;
-
- for (p = out_buf; p != out_p; p += bytes_sent) {
- bytes_sent = min(cb_chunk_size, out_p - p);
- ret = cb(p, bytes_sent, ctx_or_buf);
- 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;
}
- out_p = out_buf;
}
- }
- cur_read_offset += chunk_csize;
- } else {
- u8 dummy;
-
- /* Skip data only. */
- cur_read_offset += chunk_csize;
- ret = full_pread(in_fd, &dummy, 1, cur_read_offset - 1);
- if (ret)
- goto read_error;
+ } while (cur_range_pos < chunk_end_offset);
}
}
if (is_pipe_read
- && size == rspec->uncompressed_size
+ && last_offset == rspec->uncompressed_size - 1
&& chunk_table_size)
{
u8 dummy;
errno_save = errno;
if (chunk_offsets_malloced)
FREE(chunk_offsets);
- if (out_buf_malloced)
- FREE(out_buf);
- if (compressed_buf_malloced)
- FREE(compressed_buf);
- if (tmp_buf_malloced)
- FREE(tmp_buf);
+ 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!", size);
+ "from compressed resource!", last_offset - first_offset + 1);
errno = ENOMEM;
ret = WIMLIB_ERR_NOMEM;
goto out_free_memory;
return ret;
}
+static int
+bufferer_cb(const void *chunk, size_t size, void *_ctx)
+{
+ 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
+rechunker_cb(const void *chunk, size_t size, void *_ctx)
+{
+ struct rechunker_context *ctx = _ctx;
+ const u8 *chunkptr = chunk;
+ size_t bytes_to_copy;
+ int ret;
+
+ 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;
+
+ 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()-
*
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 == rspec->uncompressed_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. */
} else {
/* Normal mode: read must not overrun end of original size. */
wimlib_assert(offset + size >= size &&
- lte->offset_in_res + offset + size <= rspec->uncompressed_size);
+ offset + size <= lte->size);
}
DEBUG("Reading WIM resource: %"PRIu64" @ +%"PRIu64"[+%"PRIu64"] "
cb,
cb_chunk_size,
ctx_or_buf,
- offset + rspec->offset_in_wim);
+ rspec->offset_in_wim + lte->offset_in_res + offset);
} else {
- return read_compressed_wim_resource(rspec, size, cb,
- cb_chunk_size,
- ctx_or_buf, flags, offset + lte->offset_in_res);
+ 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 {
+ 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 = 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 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 {
SHA_CTX sha_ctx;
consume_data_callback_t extract_chunk;
git://wimlib.net / wimlib / blobdiff