#endif
#include "wimlib.h"
-#include "wimlib/dentry.h"
#include "wimlib/endianness.h"
#include "wimlib/error.h"
#include "wimlib/file_io.h"
#endif
#include <errno.h>
#include <fcntl.h>
-#include <stdarg.h>
#include <stdlib.h>
#include <unistd.h>
/*
- * Compressed resources
+ * Compressed WIM resources
*
- * A compressed resource in a WIM consists of a number of consecutive LZX or
- * XPRESS-compressed chunks, each of which decompresses to 32768 bytes of data,
- * except possibly the last, which always decompresses to any remaining bytes.
- * In addition, immediately before the chunks, a table (the "chunk table")
- * provides the offset, in bytes relative to the end of the chunk table, of the
- * start of each compressed chunk, except for the first chunk which is omitted
- * as it always has an offset of 0. Therefore, a compressed resource with N
- * chunks will have a chunk table with N - 1 entries.
+ * 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:
*
* writing. To make sequential writing possible, the chunk table is placed
* after the chunks rather than before the chunks, and to make sequential
* reading possible, each chunk is prefixed with a 4-byte header giving its
- * compressed size as a 32-bit, unsigned, little-endian integer (less than or
- * equal to 32768). Otherwise the details are the same.
+ * compressed size as a 32-bit, unsigned, little-endian integer. Otherwise the
+ * details are the same.
*/
-static int decompress(const void *cchunk, unsigned clen,
- void *uchunk, unsigned ulen,
- int ctype, u32 wim_chunk_size)
+
+/* 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
+decompress(const void *cchunk, unsigned clen,
+ void *uchunk, unsigned ulen,
+ int ctype, u32 wim_chunk_size)
{
switch (ctype) {
case WIMLIB_COMPRESSION_TYPE_XPRESS:
}
}
-/*
- * read_compressed_resource()-
- *
- * Read data from a compressed resource being read from a seekable WIM file.
- * The resource may be either pipable or non-pipable.
- *
- * @flags may be:
- *
- * 0:
- * Just do a normal read, decompressing the data if necessary.
- *
- * WIMLIB_READ_RESOURCE_FLAG_RAW_CHUNKS:
- * Read the raw contents of the compressed chunks of the compressed
- * resource. For pipable resources, this does *not* include the chunk
- * headers. If a callback function is being used, it will be called once
- * for each compressed chunk. For non-pipable resources, this mode
- * excludes the chunk table. For pipable resources, this mode excludes the
- * stream and chunk headers.
- */
+/* Read data from a compressed WIM resource. Assumes parameters were already
+ * verified by read_partial_wim_resource(). */
static int
-read_compressed_resource(const struct wim_lookup_table_entry * const lte,
- u64 size, const consume_data_callback_t cb,
- const u32 in_chunk_size, void * const ctx_or_buf,
- const int flags, const u64 offset)
+read_compressed_wim_resource(const struct wim_lookup_table_entry * const lte,
+ 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)
{
int ret;
+ int errno_save;
const u32 orig_chunk_size = wim_resource_chunk_size(lte);
const u32 orig_chunk_order = bsr32(orig_chunk_size);
wimlib_assert(is_power_of_2(orig_chunk_size));
- wimlib_assert(cb == NULL || is_power_of_2(in_chunk_size));
-
- /* Currently, reading raw compressed chunks is only guaranteed to work
- * correctly when the full resource is requested. Furthermore, in such
- * cases the requested size is specified as the compressed size, but
- * here we change it to an uncompressed size to avoid confusing the rest
- * of this function. */
- if (flags & WIMLIB_READ_RESOURCE_FLAG_RAW_CHUNKS) {
- wimlib_assert(offset == 0);
- wimlib_assert(size == lte->resource_entry.size);
- wimlib_assert(wim_resource_chunk_size(lte) == in_chunk_size);
- size = wim_resource_size(lte);
- }
-
- wimlib_assert(offset + size <= wim_resource_size(lte));
/* Handle the trivial case. */
if (size == 0)
bool out_buf_malloced = false;
bool tmp_buf_malloced = false;
bool compressed_buf_malloced = false;
- const size_t stack_max = 32768;
/* Get the file descriptor for the WIM. */
struct filedes * const in_fd = <e->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);
+
/* Calculate the number of chunks the resource is divided into. */
const u64 num_chunks = wim_resource_chunks(lte);
- /* 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;
-
/* Calculate the 0-based index of the chunk at which the read starts.
*/
const u64 start_chunk = offset >> orig_chunk_order;
+ /* For pipe reads, we always must start from the 0th chunk. */
+ const u64 actual_start_chunk = (is_pipe_read ? 0 : start_chunk);
+
/* 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);
* read. */
const u32 end_offset_in_chunk = (offset + size - 1) & (orig_chunk_size - 1);
- /* 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);
+ /* 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;
/* Set the size of each chunk table entry based on the resource's
* uncompressed size. */
- const u64 chunk_entry_size = (wim_resource_size(lte) > ((u64)1 << 32)) ? 8 : 4;
+ const u64 chunk_entry_size = (wim_resource_size(lte) > (1ULL << 32)) ? 8 : 4;
/* Calculate the size, in bytes, of the full chunk table. */
const u64 chunk_table_size = num_chunk_entries * chunk_entry_size;
- /* Allocate a buffer to hold a subset of the chunk table. It will only
- * contain offsets for the chunks that are actually needed for this
- * read. For speed, allocate the buffer on the stack unless it's too
- * large. */
- if (num_alloc_chunk_entries <= stack_max) {
- chunk_offsets = alloca(num_alloc_chunk_entries * sizeof(u64));
- chunk_offsets_malloced = false;
- } else {
- chunk_offsets = MALLOC(num_alloc_chunk_entries * sizeof(u64));
- if (!chunk_offsets) {
- ERROR("Failed to allocate chunk table "
- "with %"PRIu64" entries", num_alloc_chunk_entries);
- return WIMLIB_ERR_NOMEM;
+ /* Current offset to read from. */
+ u64 cur_read_offset = lte->resource_entry.offset;
+ 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)))
+ goto oom;
+
+ if (num_alloc_chunk_entries <= STACK_MAX / sizeof(u64)) {
+ chunk_offsets = alloca(num_alloc_chunk_entries * sizeof(u64));
+ } else {
+ chunk_offsets = MALLOC(num_alloc_chunk_entries * sizeof(u64));
+ if (chunk_offsets == NULL)
+ goto oom;
+ chunk_offsets_malloced = true;
}
- 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;
+ /* 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 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) ?
+ /* 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 =
+ /* 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;
- if ((u64)chunk_table_needed_size !=
- num_needed_chunk_entries * chunk_entry_size)
- {
- ERROR("Compressed read request too large to fit into memory!");
- ret = WIMLIB_ERR_NOMEM;
- goto out_free_memory;
- }
- /* 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 u64 file_offset_of_needed_chunk_entries =
- lte->resource_entry.offset
- + (start_table_idx * chunk_entry_size)
- + (lte->is_pipable ? (lte->resource_entry.size - 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,
- 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;
-
- if (chunk_entry_size == 4) {
- aliased_le32_t *raw_entries = (aliased_le32_t*)chunk_tab_data;
- for (i = 0; i < num_needed_chunk_entries; i++)
- chunk_offsets_p[i] = le32_to_cpu(raw_entries[i]);
- } else {
- aliased_le64_t *raw_entries = (aliased_le64_t*)chunk_tab_data;
- for (i = 0; i < num_needed_chunk_entries; i++)
- chunk_offsets_p[i] = le64_to_cpu(raw_entries[i]);
+ /* 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 u64 file_offset_of_needed_chunk_entries =
+ lte->resource_entry.offset
+ + (start_table_idx * chunk_entry_size)
+ + (lte->is_pipable ? (lte->resource_entry.size - 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,
+ 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;
+
+ if (chunk_entry_size == 4) {
+ aliased_le32_t *raw_entries = (aliased_le32_t*)chunk_tab_data;
+ for (i = 0; i < num_needed_chunk_entries; i++)
+ chunk_offsets_p[i] = le32_to_cpu(raw_entries[i]);
+ } else {
+ aliased_le64_t *raw_entries = (aliased_le64_t*)chunk_tab_data;
+ for (i = 0; i < num_needed_chunk_entries; i++)
+ chunk_offsets_p[i] = le64_to_cpu(raw_entries[i]);
+ }
}
- }
- /* Calculate file offset of the first chunk that needs to be read.
- * Note: if the resource is pipable, the entries in the chunk table do
- * *not* include the chunk headers. */
- u64 cur_read_offset = lte->resource_entry.offset + chunk_offsets[0];
- if (!lte->is_pipable)
- cur_read_offset += chunk_table_size;
- else
- cur_read_offset += start_chunk * sizeof(struct pwm_chunk_hdr);
+ /* Set offset to beginning of first chunk to read. */
+ cur_read_offset += chunk_offsets[0];
+ if (lte->is_pipable)
+ cur_read_offset += 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
- * be used to pass data to it. If writing directly to a buffer instead,
- * arrange to write data directly into it. */
+ * 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(in_chunk_size, orig_chunk_size);
- if (out_buf_size <= stack_max) {
+ 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) {
- ret = WIMLIB_ERR_NOMEM;
- goto out_free_memory;
- }
+ if (out_buf == NULL)
+ goto oom;
out_buf_malloced = true;
}
} else {
/* 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.
- */
+ * @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) {
+ if (orig_chunk_size - 1 <= STACK_MAX) {
compressed_buf = alloca(orig_chunk_size - 1);
} else {
compressed_buf = MALLOC(orig_chunk_size - 1);
- if (compressed_buf == NULL) {
- ret = WIMLIB_ERR_NOMEM;
- goto out_free_memory;
- }
+ if (compressed_buf == NULL)
+ goto oom;
compressed_buf_malloced = true;
}
}
- /* Allocate yet another temporary buffer, this one for reading partial
- * chunks. */
+ /* 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 != wim_resource_size(lte)))
{
- if (orig_chunk_size <= stack_max) {
+ if (orig_chunk_size <= STACK_MAX) {
tmp_buf = alloca(orig_chunk_size);
} else {
tmp_buf = MALLOC(orig_chunk_size);
- if (tmp_buf == NULL) {
- ret = WIMLIB_ERR_NOMEM;
- goto out_free_memory;
- }
+ if (tmp_buf == NULL)
+ goto oom;
tmp_buf_malloced = true;
}
}
/* Read, and possibly decompress, each needed chunk, either writing the
* data directly into the @ctx_or_buf buffer or passing it to the @cb
* callback function. */
- for (u64 i = start_chunk; i <= end_chunk; i++) {
+ for (u64 i = actual_start_chunk; i <= end_chunk; i++) {
- /* If the resource is pipable, skip the chunk header. */
- if (lte->is_pipable)
- cur_read_offset += sizeof(struct pwm_chunk_hdr);
-
- /* Calculate the sizes of the compressed chunk and of the
- * uncompressed chunk. */
- u32 compressed_chunk_size;
- u32 uncompressed_chunk_size;
- if (i != num_chunks - 1) {
- /* Not the last chunk. Compressed size is given by
- * difference of chunk table entries; uncompressed size
- * is always the WIM chunk size. */
- compressed_chunk_size = chunk_offsets[i + 1 - start_chunk] -
- chunk_offsets[i - start_chunk];
- uncompressed_chunk_size = orig_chunk_size;
- } else {
- /* Last chunk. Compressed size is the remaining size in
- * the compressed resource; uncompressed size is the
- * remaining size in the uncompressed resource. */
- compressed_chunk_size = lte->resource_entry.size -
- chunk_table_size -
- chunk_offsets[i - start_chunk];
- if (lte->is_pipable)
- compressed_chunk_size -= num_chunks *
- sizeof(struct pwm_chunk_hdr);
-
- if ((wim_resource_size(lte) & (orig_chunk_size - 1)) == 0)
- uncompressed_chunk_size = orig_chunk_size;
- else
- uncompressed_chunk_size = wim_resource_size(lte) &
- (orig_chunk_size - 1);
- }
-
- /* Calculate how much of this chunk needs to be read. */
+ /* Calculate uncompressed size of next chunk. */
+ u32 chunk_usize;
+ if ((i == num_chunks - 1) && (wim_resource_size(lte) & (orig_chunk_size - 1)))
+ chunk_usize = (wim_resource_size(lte) & (orig_chunk_size - 1));
+ else
+ chunk_usize = orig_chunk_size;
- u32 partial_chunk_size;
- u32 start_offset = 0;
- u32 end_offset = orig_chunk_size - 1;
+ /* Calculate compressed size of next chunk. */
+ u32 chunk_csize;
+ if (is_pipe_read) {
+ struct pwm_chunk_hdr chunk_hdr;
- if (flags & WIMLIB_READ_RESOURCE_FLAG_RAW_CHUNKS) {
- partial_chunk_size = compressed_chunk_size;
+ 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 {
- if (i == start_chunk)
- start_offset = start_offset_in_chunk;
+ if (i == num_chunks - 1) {
+ chunk_csize = lte->resource_entry.size -
+ chunk_table_size -
+ chunk_offsets[i - start_chunk];
+ if (lte->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];
+ }
+ }
+ 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 (lte->is_pipable)
+ cur_read_offset += sizeof(struct pwm_chunk_hdr);
- if (i == end_chunk)
- end_offset = end_offset_in_chunk;
+ 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;
- partial_chunk_size = end_offset + 1 - start_offset;
- }
+ if (flags & WIMLIB_READ_RESOURCE_FLAG_RAW_CHUNKS) {
+ chunk_needed_size = chunk_csize;
+ } else {
+ if (i == start_chunk)
+ start_offset = start_offset_in_chunk;
- if (compressed_chunk_size == uncompressed_chunk_size ||
- (flags & WIMLIB_READ_RESOURCE_FLAG_RAW_CHUNKS))
- {
- /* Chunk stored uncompressed, or reading raw chunk data. */
- ret = full_pread(in_fd,
- out_p,
- partial_chunk_size,
- cur_read_offset + start_offset);
- if (ret)
- goto read_error;
- } else {
- /* Compressed chunk and not doing raw read. */
- u8 *target;
-
- /* Read the compressed data into compressed_buf. */
- ret = full_pread(in_fd,
- compressed_buf,
- compressed_chunk_size,
- cur_read_offset);
- if (ret)
- goto read_error;
+ if (i == end_chunk)
+ end_offset = end_offset_in_chunk;
- /* For partial chunks we must buffer the uncompressed
- * data because we don't need all of it. */
- if (partial_chunk_size == uncompressed_chunk_size)
- target = out_p;
- else
- target = tmp_buf;
-
- /* Decompress the chunk. */
- ret = decompress(compressed_buf,
- compressed_chunk_size,
- target,
- uncompressed_chunk_size,
- wim_resource_compression_type(lte),
- orig_chunk_size);
- if (ret) {
- ERROR("Failed to decompress data.");
- ret = WIMLIB_ERR_DECOMPRESSION;
- errno = EINVAL;
- goto out_free_memory;
+ chunk_needed_size = end_offset + 1 - start_offset;
}
- if (partial_chunk_size != uncompressed_chunk_size)
- memcpy(out_p, tmp_buf + start_offset,
- partial_chunk_size);
- }
- out_p += partial_chunk_size;
+ if (chunk_csize == chunk_usize ||
+ (flags & WIMLIB_READ_RESOURCE_FLAG_RAW_CHUNKS))
+ {
+ /* Read the raw chunk data. */
- if (cb) {
- /* Feed the data to the callback function. */
- wimlib_assert(offset == 0);
+ ret = full_pread(in_fd,
+ out_p,
+ chunk_needed_size,
+ cur_read_offset + start_offset);
+ if (ret)
+ goto read_error;
+ } else {
+ /* Read and decompress the chunk. */
- if (flags & WIMLIB_READ_RESOURCE_FLAG_RAW_CHUNKS) {
- ret = cb(out_buf, out_p - out_buf, ctx_or_buf);
+ u8 *target;
+
+ 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 = decompress(compressed_buf,
+ chunk_csize,
+ target,
+ chunk_usize,
+ wim_resource_compression_type(lte),
+ orig_chunk_size);
+ if (ret) {
+ ERROR("Failed to decompress data!");
+ ret = WIMLIB_ERR_DECOMPRESSION;
+ errno = EINVAL;
goto out_free_memory;
- out_p = out_buf;
+ }
+ if (chunk_needed_size != chunk_usize)
+ memcpy(out_p, tmp_buf + start_offset,
+ chunk_needed_size);
+ }
+
+ out_p += chunk_needed_size;
- } else if (i == end_chunk || out_p == out_buf_end) {
- size_t bytes_sent;
- const u8 *p;
+ if (cb) {
+ /* Feed the data to the callback function. */
- for (p = out_buf; p != out_p; p += bytes_sent) {
- bytes_sent = min(in_chunk_size, out_p - p);
- ret = cb(p, bytes_sent, ctx_or_buf);
+ 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;
+ }
+ out_p = out_buf;
}
- 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;
}
- cur_read_offset += compressed_chunk_size;
}
+ if (is_pipe_read
+ && size == lte->resource_entry.original_size
+ && 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_free_memory:
+ errno_save = errno;
if (chunk_offsets_malloced)
FREE(chunk_offsets);
if (out_buf_malloced)
FREE(compressed_buf);
if (tmp_buf_malloced)
FREE(tmp_buf);
+ errno = errno_save;
return ret;
-read_error:
- ERROR_WITH_ERRNO("Error reading compressed file resource");
+oom:
+ ERROR("Not enough memory available to read size=%"PRIu64" bytes "
+ "from compressed resource!", size);
+ errno = ENOMEM;
+ ret = WIMLIB_ERR_NOMEM;
goto out_free_memory;
-}
-/* Skip over the chunk table at the end of pipable, compressed resource being
- * read from a pipe. */
-static int
-skip_chunk_table(const struct wim_lookup_table_entry *lte,
- struct filedes *in_fd)
-{
- u64 num_chunk_entries = wim_resource_chunks(lte) - 1;
- u64 chunk_entry_size = (wim_resource_size(lte) > ((u64)1 << 32)) ? 8 : 4;
- u64 chunk_table_size = num_chunk_entries * chunk_entry_size;
- int ret;
-
- if (num_chunk_entries != 0) {
- u8 dummy;
- ret = full_pread(in_fd, &dummy, 1,
- in_fd->offset + chunk_table_size - 1);
- if (ret)
- return ret;
- }
- return 0;
+read_error:
+ ERROR_WITH_ERRNO("Error reading compressed file resource!");
+ goto out_free_memory;
}
-/* Read and decompress data from a compressed, pipable resource being read from
- * a pipe. */
+/* Read raw data from a file descriptor at the specified offset. */
static int
-read_pipable_resource(const struct wim_lookup_table_entry *lte,
- u64 size, consume_data_callback_t cb,
- u32 in_chunk_size, void *ctx_or_buf,
- int flags, u64 offset)
+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)
{
- struct filedes *in_fd;
int ret;
- const u32 orig_chunk_size = wim_resource_chunk_size(lte);
- u8 cchunk[orig_chunk_size - 1];
+ u8 *tmp_buf;
+ bool tmp_buf_malloced = false;
- size_t out_buf_size;
- u8 *out_buf, *out_buf_end, *out_p;
if (cb) {
- out_buf_size = max(in_chunk_size, orig_chunk_size);
- out_buf = alloca(out_buf_size);
- } else {
- out_buf_size = size;
- out_buf = ctx_or_buf;
- }
- out_buf_end = out_buf + out_buf_size;
- out_p = out_buf;
-
- /* Get pointers to appropriate decompression function and the input file
- * descriptor. */
- in_fd = <e->wim->in_fd;
-
- /* This function currently assumes the entire resource is being read at
- * once and that the raw compressed data isn't being requested. This is
- * based on the fact that this function currently only gets called
- * during the operation of wimlib_extract_image_from_pipe(). */
- wimlib_assert(!(flags & WIMLIB_READ_RESOURCE_FLAG_RAW));
- wimlib_assert(offset == 0);
- wimlib_assert(size == wim_resource_size(lte));
- wimlib_assert(in_fd->offset == lte->resource_entry.offset);
-
- u32 chunk_usize;
- for (offset = 0; offset < size; offset += chunk_usize) {
- struct pwm_chunk_hdr chunk_hdr;
- u32 chunk_csize;
-
- /* Calculate uncompressed size of next chunk. */
- chunk_usize = min(orig_chunk_size, size - offset);
-
- /* Read the compressed size of the next chunk from the chunk
- * header. */
- ret = full_read(in_fd, &chunk_hdr, sizeof(chunk_hdr));
- if (ret)
- goto read_error;
-
- chunk_csize = le32_to_cpu(chunk_hdr.compressed_size);
-
- if (chunk_csize > orig_chunk_size) {
- errno = EINVAL;
- ret = WIMLIB_ERR_INVALID_PIPABLE_WIM;
- goto invalid;
- }
-
- /* Read chunk data. */
- ret = full_read(in_fd, cchunk, chunk_csize);
- if (ret)
- goto read_error;
-
- if (flags & WIMLIB_READ_RESOURCE_FLAG_SEEK_ONLY)
- continue;
-
- /* Decompress chunk if needed. Uncompressed size same
- * as compressed size means the chunk is uncompressed.
- */
- if (chunk_csize == chunk_usize) {
- memcpy(out_p, cchunk, chunk_usize);
+ /* Send data to callback function in chunks. */
+ if (cb_chunk_size <= STACK_MAX) {
+ tmp_buf = alloca(cb_chunk_size);
} else {
- ret = (*decompress)(cchunk, chunk_csize,
- out_p, chunk_usize,
- wim_resource_compression_type(lte),
- orig_chunk_size);
- if (ret) {
- errno = EINVAL;
- ret = WIMLIB_ERR_DECOMPRESSION;
- goto invalid;
+ tmp_buf = MALLOC(cb_chunk_size);
+ if (tmp_buf == NULL) {
+ ret = WIMLIB_ERR_NOMEM;
+ goto out;
}
+ tmp_buf_malloced = true;
}
- out_p += chunk_usize;
-
- /* Feed the uncompressed data into the callback function or copy
- * it into the provided buffer. */
- if (cb && (out_p == out_buf_end ||
- offset + chunk_usize == size))
- {
- size_t bytes_sent;
- const u8 *p;
- for (p = out_buf; p != out_p; p += bytes_sent) {
- bytes_sent = min(in_chunk_size, out_p - p);
- ret = cb(p, bytes_sent, ctx_or_buf);
- if (ret)
- return ret;
- }
- out_p = out_buf;
+ 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;
}
-
- ret = skip_chunk_table(lte, in_fd);
- if (ret)
- goto read_error;
- return 0;
+ ret = 0;
+ goto out;
read_error:
- ERROR_WITH_ERRNO("Error reading compressed file resource");
- return ret;
-
-invalid:
- ERROR("Compressed file resource is invalid");
+ ERROR_WITH_ERRNO("Read error");
+out:
+ if (tmp_buf_malloced)
+ FREE(tmp_buf);
return ret;
}
/*
* read_partial_wim_resource()-
*
- * Read a range of data from a uncompressed or compressed resource in a WIM
+ * 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_resource_prefix().
*
- * @flags can be:
- *
- * 0:
- * Just do a normal read, decompressing the data if necessary. @size and
- * @offset are interpreted relative to the uncompressed contents of the
- * stream.
+ * 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:
- * Only valid when the resource is compressed: Read the raw contents of
- * the compressed resource. If the resource is non-pipable, this includes
- * the chunk table as well as the compressed chunks. If the resource is
- * pipable, this includes the compressed chunks--- including the chunk
- * headers--- and the chunk table. The stream header is still *not*
- * included.
- *
- * In this mode, @offset is relative to the beginning of the raw contents
- * of the compressed resource--- that is, the chunk table if the resource
- * is non-pipable, or the header for the first compressed chunk if the
- * resource is pipable. @size is the number of raw bytes to read, which
- * must not overrun the end of the resource. For example, if @offset is 0,
- * then @size can be at most the raw size of the compressed resource
- * (@lte->resource_entry.size).
+ * 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:
- * Only valid when the resource is compressed and is not being read from a
- * pipe: Read the raw contents of the compressed chunks of the compressed
- * resource. For pipable resources, this does *not* include the chunk
- * headers. If a callback function is being used, it will be called once
- * for each compressed chunk. The chunk table is excluded. Also, for
- * pipable resources, the stream and chunk headers are excluded. In this
- * mode, @size must be exactly the raw size of the compressed resource
- * (@lte->resource_entry.size) and @offset must be 0.
- *
- * WIMLIB_READ_RESOURCE_FLAG_SEEK_ONLY:
- * Only valid when the resource is being read from a pipe: Skip over the
- * requested data rather than feed it to the callback function or write it
- * into the buffer. No decompression is done.
- * WIMLIB_READ_RESOURCE_FLAG_RAW_* may not be combined with this flag.
- * @offset must be 0 and @size must be the uncompressed size of the
- * resource.
+ * 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_UNEXPECTED_END_OF_FILE (errno set to 0)
* WIMLIB_ERR_NOMEM (errno set to ENOMEM)
* WIMLIB_ERR_DECOMPRESSION (errno set to EINVAL)
- * WIMLIB_ERR_INVALID_PIPABLE_WIM (errno set to EINVAL)
*
* or other error code returned by the @cb function.
*/
int
read_partial_wim_resource(const struct wim_lookup_table_entry *lte,
u64 size, consume_data_callback_t cb,
- u32 in_chunk_size,
+ u32 cb_chunk_size,
void *ctx_or_buf, int flags, u64 offset)
{
struct filedes *in_fd;
- int ret;
- /* Make sure the resource is actually located in a WIM file and is not
- * somewhere else. */
+ /* Verify parameters. */
wimlib_assert(lte->resource_location == RESOURCE_IN_WIM);
-
- /* If a callback was specified, in_chunk_size must be a power of 2 (and
- * not 0). */
- wimlib_assert(cb == NULL || is_power_of_2(in_chunk_size));
-
- /* If a callback was specified, offset must be zero. */
- wimlib_assert(cb == NULL || offset == 0);
-
- /* Retrieve input file descriptor for the WIM file. */
in_fd = <e->wim->in_fd;
-
- /* Don't allow raw reads (either full or chunks) of uncompressed
- * resources. */
- wimlib_assert(!(flags & WIMLIB_READ_RESOURCE_FLAG_RAW) ||
- resource_is_compressed(<e->resource_entry));
-
- /* Don't allow seek-only reads unless reading from a pipe; also don't
- * allow combining SEEK_ONLY with either RAW flag. */
- wimlib_assert(!(flags & WIMLIB_READ_RESOURCE_FLAG_SEEK_ONLY) ||
- (!filedes_is_seekable(in_fd) &&
- !(flags & WIMLIB_READ_RESOURCE_FLAG_RAW)));
+ 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(!(flags & WIMLIB_READ_RESOURCE_FLAG_RAW_FULL));
+ wimlib_assert(cb_chunk_size == wim_resource_chunk_size(lte));
+ wimlib_assert(size == lte->resource_entry.original_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(offset + size >= size &&
+ offset + size <= lte->resource_entry.size);
+ } else {
+ /* Normal mode: read must not overrun end of original size. */
+ wimlib_assert(offset + size >= size &&
+ offset + size <= lte->resource_entry.original_size);
+ }
DEBUG("Reading WIM resource: %"PRIu64" @ +%"PRIu64" "
- "from %"PRIu64" @ +%"PRIu64" (readflags 0x%08x, resflags 0x%02x%s)",
+ "from %"PRIu64"(%"PRIu64") @ +%"PRIu64" "
+ "(readflags 0x%08x, resflags 0x%02x%s)",
size, offset,
- lte->resource_entry.original_size, lte->resource_entry.offset,
+ lte->resource_entry.size,
+ lte->resource_entry.original_size,
+ lte->resource_entry.offset,
flags, lte->resource_entry.flags,
(lte->is_pipable ? ", pipable" : ""));
if ((flags & WIMLIB_READ_RESOURCE_FLAG_RAW_FULL) ||
- !resource_is_compressed(<e->resource_entry))
- {
- /* Reading raw resource contents or reading uncompressed
- * resource. */
- wimlib_assert(offset + size <= lte->resource_entry.size);
- offset += lte->resource_entry.offset;
- if (flags & WIMLIB_READ_RESOURCE_FLAG_SEEK_ONLY) {
- if (lte->resource_entry.size != 0) {
- u8 dummy;
- ret = full_pread(in_fd, &dummy, 1,
- offset + lte->resource_entry.size - 1);
- if (ret)
- goto read_error;
- }
- } else if (cb) {
- /* Send data to callback function */
- u8 buf[min(in_chunk_size, size)];
- while (size) {
- size_t bytes_to_read = min(in_chunk_size, size);
- ret = full_pread(in_fd, buf, bytes_to_read,
- offset);
- if (ret)
- goto read_error;
- ret = cb(buf, bytes_to_read, ctx_or_buf);
- if (ret)
- goto out;
- size -= bytes_to_read;
- offset += bytes_to_read;
- }
- } else {
- /* Send data directly to a buffer */
- ret = full_pread(in_fd, ctx_or_buf, size, offset);
- if (ret)
- goto read_error;
- }
- ret = 0;
- } else if (lte->is_pipable && !filedes_is_seekable(in_fd)) {
- /* Reading compressed, pipable resource from pipe. */
- ret = read_pipable_resource(lte, size, cb,
- in_chunk_size,
- ctx_or_buf, flags, offset);
+ !resource_is_compressed(<e->resource_entry)) {
+ return read_raw_file_data(in_fd,
+ size,
+ cb,
+ cb_chunk_size,
+ ctx_or_buf,
+ offset + lte->resource_entry.offset);
} else {
- /* Reading compressed, possibly pipable resource from seekable
- * file. */
- ret = read_compressed_resource(lte, size, cb,
- in_chunk_size,
- ctx_or_buf, flags, offset);
+ return read_compressed_wim_resource(lte, size, cb,
+ cb_chunk_size,
+ ctx_or_buf, flags, offset);
}
- goto out;
-
-read_error:
- ERROR_WITH_ERRNO("Error reading data from WIM");
-out:
- return ret;
}
-
int
read_partial_wim_resource_into_buf(const struct wim_lookup_table_entry *lte,
size_t size, u64 offset, void *buf)
read_wim_resource_prefix(const struct wim_lookup_table_entry *lte,
u64 size,
consume_data_callback_t cb,
- u32 in_chunk_size,
+ u32 cb_chunk_size,
void *ctx_or_buf,
int flags)
{
- return read_partial_wim_resource(lte, size, cb, in_chunk_size,
+ return read_partial_wim_resource(lte, size, cb, cb_chunk_size,
ctx_or_buf, flags, 0);
}
-
#ifndef __WIN32__
+/* This function handles reading resource 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,
- u32 in_chunk_size,
+ u32 cb_chunk_size,
void *ctx_or_buf,
int _ignored_flags)
{
- const tchar *filename = lte->file_on_disk;
int ret;
- struct filedes fd;
int raw_fd;
- u8 *out_buf;
- bool out_buf_malloced;
- const size_t stack_max = 32768;
+ struct filedes fd;
- DEBUG("Reading %"PRIu64" bytes from \"%"TS"\"",
- size, lte->file_on_disk);
+ wimlib_assert(size <= wim_resource_size(lte));
+ DEBUG("Reading %"PRIu64" bytes from \"%"TS"\"", size, lte->file_on_disk);
- raw_fd = open(filename, O_RDONLY);
+ raw_fd = open(lte->file_on_disk, O_BINARY | O_RDONLY);
if (raw_fd < 0) {
- ERROR_WITH_ERRNO("Can't open \"%"TS"\"", filename);
+ ERROR_WITH_ERRNO("Can't open \"%"TS"\"", lte->file_on_disk);
return WIMLIB_ERR_OPEN;
}
filedes_init(&fd, raw_fd);
- out_buf_malloced = false;
- if (cb) {
- /* Send data to callback function */
- if (in_chunk_size <= stack_max) {
- out_buf = alloca(in_chunk_size);
- } else {
- out_buf = MALLOC(in_chunk_size);
- if (out_buf == NULL) {
- ret = WIMLIB_ERR_NOMEM;
- goto out_close;
- }
- out_buf_malloced = true;
- }
-
- size_t bytes_to_read;
- while (size) {
- bytes_to_read = min(in_chunk_size, size);
- ret = full_read(&fd, out_buf, bytes_to_read);
- if (ret)
- goto read_error;
- ret = cb(out_buf, bytes_to_read, ctx_or_buf);
- if (ret)
- goto out_close;
- size -= bytes_to_read;
- }
- } else {
- /* Send data directly to a buffer */
- ret = full_read(&fd, ctx_or_buf, size);
- if (ret)
- goto read_error;
- }
- ret = 0;
- goto out_close;
-
-read_error:
- ERROR_WITH_ERRNO("Error reading \"%"TS"\"", filename);
-out_close:
+ ret = read_raw_file_data(&fd, size, cb, cb_chunk_size, ctx_or_buf, 0);
filedes_close(&fd);
- if (out_buf_malloced)
- FREE(out_buf);
return ret;
}
#endif /* !__WIN32__ */
+/* This function handles the trivial case of reading resource 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,
- u32 in_chunk_size,
+ u32 cb_chunk_size,
void *ctx_or_buf, int _ignored_flags)
{
+ wimlib_assert(size <= wim_resource_size(lte));
if (cb) {
+ /* 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(in_chunk_size, size - offset);
+ 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;
}
} else {
+ /* 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,
- u32 in_chunk_size,
+ u32 cb_chunk_size,
void *ctx_or_buf,
int flags);
/*
* read_resource_prefix()-
*
- * Read the first @size bytes from a generic "resource", which may be located in
- * the WIM (compressed or uncompressed), in an external file, or directly in an
- * in-memory buffer.
+ * Reads the first @size bytes from a generic "resource", 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.
*
- * 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).
+ * 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).
*
- * When using a callback function, it is called with chunks up to 32768 bytes in
- * size until the resource is exhausted.
+ * 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
+ * resource 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.
*
* If the resource is located in a WIM file, @flags can be set as documented in
* read_partial_wim_resource(). Otherwise @flags are ignored.
+ *
+ * Returns 0 on success; nonzero on error. A nonzero value will be returned if
+ * the resource data cannot be successfully read (for a number of different
+ * reasons, depending on the resource 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, u32 in_chunk_size,
+ u64 size, consume_data_callback_t cb, u32 cb_chunk_size,
void *ctx_or_buf, int flags)
{
+ /* This function merely verifies several preconditions, then passes
+ * control to an appropriate function for understanding each possible
+ * resource location. */
static const read_resource_prefix_handler_t handlers[] = {
[RESOURCE_IN_WIM] = read_wim_resource_prefix,
#ifdef __WIN32__
};
wimlib_assert(lte->resource_location < ARRAY_LEN(handlers)
&& handlers[lte->resource_location] != NULL);
- wimlib_assert(cb == NULL || in_chunk_size > 0);
- return handlers[lte->resource_location](lte, size, cb, in_chunk_size, 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 resource into the specified
+ * buffer, which must have space for at least lte->resource_entry.original_size
+ * bytes. */
int
read_full_resource_into_buf(const struct wim_lookup_table_entry *lte,
void *buf)
{
- return read_resource_prefix(lte, wim_resource_size(lte), NULL, 0, buf, 0);
+ return read_resource_prefix(lte, wim_resource_size(lte),
+ NULL, 0, buf, 0);
}
+/* Read the full uncompressed data of the specified resource. A buffer
+ * sufficient to hold the data is allocated and returned in @buf_ret. */
int
read_full_resource_into_alloc_buf(const struct wim_lookup_table_entry *lte,
void **buf_ret)
}
buf = MALLOC(lte->resource_entry.original_size);
- if (!buf)
+ if (buf == NULL)
return WIMLIB_ERR_NOMEM;
ret = read_full_resource_into_buf(lte, buf);
return 0;
}
+/* Retrieve the full uncompressed data of the specified WIM resource, provided
+ * as a raw `struct resource_entry'. */
int
res_entry_to_data(const struct resource_entry *res_entry,
WIMStruct *wim, void **buf_ret)
struct wim_lookup_table_entry *lte;
lte = new_lookup_table_entry();
- if (!lte)
+ if (lte == NULL)
return WIMLIB_ERR_NOMEM;
copy_resource_entry(<e->resource_entry, res_entry);
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
+/* Extracts the first @size bytes of a resource to somewhere. In the process,
+ * the SHA1 message digest of the uncompressed resource is checked if the full
* resource is being extracted.
*
- * @extract_chunk is a function that is called to extract each chunk of the
- * resource. */
+ * @extract_chunk is a function that will be called to extract each chunk of the
+ * resource. */
int
extract_wim_resource(const struct wim_lookup_table_entry *lte,
u64 size,
return ret;
}
+/* Extract the first @size bytes of the specified resource to the specified file
+ * descriptor. If @size is the full size of the resource, its SHA1 message
+ * digest is also checked. */
int
extract_wim_resource_to_fd(const struct wim_lookup_table_entry *lte,
struct filedes *fd, u64 size)
return 0;
}
-/* Calculate the SHA1 message digest of a stream. */
+/* Calculate the SHA1 message digest of a resource, storing it in @lte->hash. */
int
sha1_resource(struct wim_lookup_table_entry *lte)
{
&sha_ctx, 0);
if (ret == 0)
sha1_final(lte->hash, &sha_ctx);
+
return ret;
}
-/* Translates a WIM resource entry from the on-disk format to an in-memory
- * format. */
+/* Translates a WIM resource entry from the on-disk format into an in-memory
+ * format. */
void
get_resource_entry(const struct resource_entry_disk *disk_entry,
struct resource_entry *entry)
{
/* Note: disk_entry may not be 8 byte aligned--- in that case, the
- * offset and original_size members will be unaligned. (This should be
- * okay since `struct resource_entry_disk' is declared as packed.) */
+ * offset and original_size members will be unaligned. (This is okay
+ * since `struct resource_entry_disk' is declared as packed.) */
/* Read the size and flags into a bitfield portably... */
entry->size = (((u64)disk_entry->size[0] << 0) |
struct resource_entry_disk *disk_entry)
{
/* Note: disk_entry may not be 8 byte aligned--- in that case, the
- * offset and original_size members will be unaligned. (This should be
- * okay since `struct resource_entry_disk' is declared as packed.) */
+ * offset and original_size members will be unaligned. (This is okay
+ * since `struct resource_entry_disk' is declared as packed.) */
u64 size = entry->size;
disk_entry->size[0] = size >> 0;
git://wimlib.net / wimlib / blobdiff