struct lzx_tables {
u16 maintree_decode_table[(1 << LZX_MAINCODE_TABLEBITS) +
- (LZX_MAINCODE_NUM_SYMBOLS * 2)]
+ (LZX_MAINCODE_MAX_NUM_SYMBOLS * 2)]
_aligned_attribute(DECODE_TABLE_ALIGNMENT);
- u8 maintree_lens[LZX_MAINCODE_NUM_SYMBOLS];
+ u8 maintree_lens[LZX_MAINCODE_MAX_NUM_SYMBOLS];
u16 lentree_decode_table[(1 << LZX_LENCODE_TABLEBITS) +
static inline int
read_huffsym_using_maintree(struct input_bitstream *istream,
const struct lzx_tables *tables,
- unsigned *n)
+ unsigned *n,
+ unsigned num_main_syms)
{
return read_huffsym(istream, tables->maintree_decode_table,
- tables->maintree_lens, LZX_MAINCODE_NUM_SYMBOLS,
+ tables->maintree_lens, num_main_syms,
LZX_MAINCODE_TABLEBITS, n, LZX_MAX_MAIN_CODEWORD_LEN);
}
*/
static int
lzx_read_block_header(struct input_bitstream *istream,
+ unsigned num_main_syms,
+ unsigned max_window_size,
unsigned *block_size_ret,
unsigned *block_type_ret,
struct lzx_tables *tables,
unsigned i;
unsigned len;
- ret = bitstream_ensure_bits(istream, LZX_BLOCKTYPE_NBITS + 1);
+ ret = bitstream_ensure_bits(istream, 4);
if (ret) {
LZX_DEBUG("LZX input stream overrun");
return ret;
/* The first three bits tell us what kind of block it is, and are one
* of the LZX_BLOCKTYPE_* values. */
- block_type = bitstream_read_bits_nocheck(istream, LZX_BLOCKTYPE_NBITS);
+ block_type = bitstream_read_bits_nocheck(istream, 3);
- /* The next bit indicates whether the block size is the default (32768),
- * indicated by a 1 bit, or whether the block size is given by the next
- * 16 bits, indicated by a 0 bit. */
+ /* Read the block size. This mirrors the behavior
+ * lzx_write_compressed_block() in lzx-compress.c; see that for more
+ * details. */
s = bitstream_read_bits_nocheck(istream, 1);
-
if (s) {
- block_size = 32768;
+ block_size = LZX_DEFAULT_BLOCK_SIZE;
} else {
- ret = bitstream_read_bits(istream, LZX_BLOCKSIZE_NBITS, &block_size);
+ unsigned tmp;
+ block_size = 0;
+
+ ret = bitstream_read_bits(istream, 8, &tmp);
if (ret)
return ret;
- block_size = le16_to_cpu(block_size);
+ block_size |= tmp;
+
+ ret = bitstream_read_bits(istream, 8, &tmp);
+ if (ret)
+ return ret;
+ block_size <<= 8;
+ block_size |= tmp;
+
+ if (max_window_size >= 65536) {
+ ret = bitstream_read_bits(istream, 8, &tmp);
+ if (ret)
+ return ret;
+ block_size <<= 8;
+ block_size |= tmp;
+ }
}
switch (block_type) {
* tree. */
LZX_DEBUG("Reading path lengths for remaining elements of "
"main tree (%d elements).",
- LZX_MAINCODE_NUM_SYMBOLS - LZX_NUM_CHARS);
+ num_main_syms - LZX_NUM_CHARS);
ret = lzx_read_code_lens(istream,
tables->maintree_lens + LZX_NUM_CHARS,
- LZX_MAINCODE_NUM_SYMBOLS - LZX_NUM_CHARS);
+ num_main_syms - LZX_NUM_CHARS);
if (ret) {
LZX_DEBUG("Failed to read the path lengths for the "
"remaining elements of the main tree");
"table for the main tree.");
ret = make_huffman_decode_table(tables->maintree_decode_table,
- LZX_MAINCODE_NUM_SYMBOLS,
+ num_main_syms,
LZX_MAINCODE_TABLEBITS,
tables->maintree_lens,
LZX_MAX_MAIN_CODEWORD_LEN);
* @block_type: The type of the block (LZX_BLOCKTYPE_VERBATIM or
* LZX_BLOCKTYPE_ALIGNED)
* @block_size: The size of the block, in bytes.
+ * @num_main_syms: Number of symbols in the main alphabet.
* @window: Pointer to the decompression window.
* @window_pos: The current position in the window. Will be 0 for the first
* block.
*/
static int
lzx_decompress_block(int block_type, unsigned block_size,
+ unsigned num_main_syms,
u8 *window,
unsigned window_pos,
const struct lzx_tables *tables,
end = window_pos + block_size;
while (window_pos < end) {
ret = read_huffsym_using_maintree(istream, tables,
- &main_element);
+ &main_element,
+ num_main_syms);
if (ret)
return ret;
/* literal: 0 to LZX_NUM_CHARS - 1 */
window[window_pos++] = main_element;
} else {
- /* match: LZX_NUM_CHARS to LZX_MAINCODE_NUM_SYMBOLS - 1 */
+ /* match: LZX_NUM_CHARS to num_main_syms - 1 */
match_len = lzx_decode_match(main_element,
block_type,
end - window_pos,
return 0;
}
-/* API function documented in wimlib.h */
WIMLIBAPI int
-wimlib_lzx_decompress(const void *compressed_data, unsigned compressed_len,
- void *uncompressed_data, unsigned uncompressed_len)
+wimlib_lzx_decompress2(const void *compressed_data, unsigned compressed_len,
+ void *uncompressed_data, unsigned uncompressed_len,
+ u32 max_window_size)
{
struct lzx_tables tables;
struct input_bitstream istream;
unsigned window_pos;
unsigned block_size;
unsigned block_type;
+ unsigned num_main_syms;
int ret;
bool e8_preprocessing_done;
- LZX_DEBUG("lzx_decompress (compressed_data = %p, compressed_len = %d, "
- "uncompressed_data = %p, uncompressed_len = %d).",
+ LZX_DEBUG("compressed_data = %p, compressed_len = %u, "
+ "uncompressed_data = %p, uncompressed_len = %u, "
+ "max_window_size=%u).",
compressed_data, compressed_len,
- uncompressed_data, uncompressed_len);
+ uncompressed_data, uncompressed_len, max_window_size);
+
+ if (!lzx_window_size_valid(max_window_size)) {
+ LZX_DEBUG("Window size of %u is invalid!",
+ max_window_size);
+ return -1;
+ }
- wimlib_assert(uncompressed_len <= 32768);
+ num_main_syms = lzx_get_num_main_syms(max_window_size);
+
+ if (uncompressed_len > max_window_size) {
+ LZX_DEBUG("Uncompressed chunk size of %u exceeds "
+ "window size of %u!",
+ uncompressed_len, max_window_size);
+ return -1;
+ }
memset(tables.maintree_lens, 0, sizeof(tables.maintree_lens));
memset(tables.lentree_lens, 0, sizeof(tables.lentree_lens));
window_pos += block_size)
{
LZX_DEBUG("Reading block header.");
- ret = lzx_read_block_header(&istream, &block_size,
+ ret = lzx_read_block_header(&istream, num_main_syms,
+ max_window_size, &block_size,
&block_type, &tables, &queue);
if (ret)
return ret;
LZX_DEBUG("LZX_BLOCKTYPE_ALIGNED");
ret = lzx_decompress_block(block_type,
block_size,
+ num_main_syms,
uncompressed_data,
window_pos,
&tables,
&istream);
if (ret)
return ret;
+
if (tables.maintree_lens[0xe8] != 0)
e8_preprocessing_done = true;
break;
undo_call_insn_preprocessing(uncompressed_data, uncompressed_len);
return 0;
}
+
+/* API function documented in wimlib.h */
+WIMLIBAPI int
+wimlib_lzx_decompress(const void *compressed_data, unsigned compressed_len,
+ void *uncompressed_data, unsigned uncompressed_len)
+{
+ return wimlib_lzx_decompress2(compressed_data, compressed_len,
+ uncompressed_data, uncompressed_len,
+ 32768);
+}
git://wimlib.net / wimlib / blobdiff