*/
/*
- * LZX is a LZ77 and Huffman-code based compression format that has many
+ * LZX is an LZ77 and Huffman-code based compression format that has many
* similarities to the DEFLATE format used in zlib. The compression ratio is as
* good or better than DEFLATE.
*
* last decompress to a fixed number of bytes, by default 32768. This is quite
* similar to the cabinet (.cab) file format, but they are not the same.
* According to the cabinet format documentation, the LZX block size is
- * independent from the CFDATA blocks, and a LZX block may span several CFDATA
+ * independent from the CFDATA blocks, and an LZX block may span several CFDATA
* blocks. However, in WIMs, LZX blocks do not appear to ever span multiple WIM
* chunks. Note that this means any WIM chunk may be decompressed or compressed
* independently from any other chunk, which allows random access.
*
- * A LZX compressed WIM chunk contains one or more LZX blocks of the aligned,
+ * An LZX compressed WIM chunk contains one or more LZX blocks of the aligned,
* verbatim, or uncompressed block types. For aligned and verbatim blocks, the
* size of the block in uncompressed bytes is specified by a bit following the 3
* bits that specify the block type, possibly followed by an additional 16 bits.
#endif
#include "wimlib.h"
-#include "wimlib/decompress.h"
+#include "wimlib/decompressor_ops.h"
+#include "wimlib/decompress_common.h"
#include "wimlib/lzx.h"
#include "wimlib/util.h"
u8 alignedtree_lens[LZX_ALIGNEDCODE_NUM_SYMBOLS];
} _aligned_attribute(DECODE_TABLE_ALIGNMENT);
+struct lzx_decompressor {
+ u32 max_window_size;
+ unsigned num_main_syms;
+ struct lzx_tables tables;
+};
/*
* Reads a Huffman-encoded symbol using the pre-tree.
* in bytes, will be returned.
* @block_type_ret: A pointer to an int into which the type of the block
* (LZX_BLOCKTYPE_*) will be returned.
- * @tables: A pointer to a lzx_tables structure in which the
+ * @tables: A pointer to an lzx_tables structure in which the
* main tree, the length tree, and possibly the
* aligned offset tree will be constructed.
* @queue: A pointer to the least-recently-used queue into which
}
static void
-undo_call_insn_translation(u32 *call_insn_target, int input_pos,
+undo_call_insn_translation(u32 *call_insn_target, s32 input_pos,
s32 file_size)
{
s32 abs_offset;
* as it is used in calculating the translated jump targets. But in WIM files,
* this file size is always the same (LZX_WIM_MAGIC_FILESIZE == 12000000).*/
static void
-undo_call_insn_preprocessing(u8 uncompressed_data[], int uncompressed_data_len)
+undo_call_insn_preprocessing(u8 *uncompressed_data, s32 uncompressed_size)
{
- for (int i = 0; i < uncompressed_data_len - 10; i++) {
+ for (s32 i = 0; i < uncompressed_size - 10; i++) {
if (uncompressed_data[i] == 0xe8) {
undo_call_insn_translation((u32*)&uncompressed_data[i + 1],
i,
}
/*
- * Decompresses a LZX-compressed block of data from which the header has already
+ * Decompresses an LZX-compressed block of data from which the header has already
* been read.
*
* @block_type: The type of the block (LZX_BLOCKTYPE_VERBATIM or
return 0;
}
-/* API function documented in wimlib.h */
-WIMLIBAPI int
-wimlib_lzx_decompress2(const void *compressed_data, unsigned compressed_len,
- void *uncompressed_data, unsigned uncompressed_len,
- u32 max_window_size)
+static int
+lzx_decompress(const void *compressed_data, size_t compressed_size,
+ void *uncompressed_data, size_t uncompressed_size,
+ void *_ctx)
{
- struct lzx_tables tables;
+ struct lzx_decompressor *ctx = _ctx;
struct input_bitstream istream;
struct lzx_lru_queue queue;
unsigned window_pos;
unsigned block_size;
unsigned block_type;
- unsigned num_main_syms;
int ret;
bool e8_preprocessing_done;
- LZX_DEBUG("compressed_data = %p, compressed_len = %u, "
- "uncompressed_data = %p, uncompressed_len = %u, "
+ LZX_DEBUG("compressed_data = %p, compressed_size = %zu, "
+ "uncompressed_data = %p, uncompressed_size = %zu, "
"max_window_size=%u).",
- compressed_data, compressed_len,
- uncompressed_data, uncompressed_len, max_window_size);
+ compressed_data, compressed_size,
+ uncompressed_data, uncompressed_size,
+ ctx->max_window_size);
- if (!lzx_window_size_valid(max_window_size)) {
- LZX_DEBUG("Window size of %u is invalid!",
- max_window_size);
- return -1;
- }
-
- 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 "
+ if (uncompressed_size > ctx->max_window_size) {
+ LZX_DEBUG("Uncompressed size of %zu exceeds "
"window size of %u!",
- uncompressed_len, max_window_size);
+ uncompressed_size, ctx->max_window_size);
return -1;
}
- memset(tables.maintree_lens, 0, sizeof(tables.maintree_lens));
- memset(tables.lentree_lens, 0, sizeof(tables.lentree_lens));
+ memset(ctx->tables.maintree_lens, 0, sizeof(ctx->tables.maintree_lens));
+ memset(ctx->tables.lentree_lens, 0, sizeof(ctx->tables.lentree_lens));
lzx_lru_queue_init(&queue);
- init_input_bitstream(&istream, compressed_data, compressed_len);
+ init_input_bitstream(&istream, compressed_data, compressed_size);
e8_preprocessing_done = false; /* Set to true if there may be 0xe8 bytes
in the uncompressed data. */
* blocks. */
for (window_pos = 0;
- window_pos < uncompressed_len;
+ window_pos < uncompressed_size;
window_pos += block_size)
{
LZX_DEBUG("Reading block header.");
- ret = lzx_read_block_header(&istream, num_main_syms,
- max_window_size, &block_size,
- &block_type, &tables, &queue);
+ ret = lzx_read_block_header(&istream, ctx->num_main_syms,
+ ctx->max_window_size, &block_size,
+ &block_type, &ctx->tables, &queue);
if (ret)
return ret;
LZX_DEBUG("block_size = %u, window_pos = %u",
block_size, window_pos);
- if (block_size > uncompressed_len - window_pos) {
+ if (block_size > uncompressed_size - window_pos) {
LZX_DEBUG("Expected a block size of at "
- "most %u bytes (found %u bytes)",
- uncompressed_len - window_pos, block_size);
+ "most %zu bytes (found %u bytes)",
+ uncompressed_size - window_pos, block_size);
return -1;
}
LZX_DEBUG("LZX_BLOCKTYPE_ALIGNED");
ret = lzx_decompress_block(block_type,
block_size,
- num_main_syms,
+ ctx->num_main_syms,
uncompressed_data,
window_pos,
- &tables,
+ &ctx->tables,
&queue,
&istream);
if (ret)
return ret;
- if (tables.maintree_lens[0xe8] != 0)
+ if (ctx->tables.maintree_lens[0xe8] != 0)
e8_preprocessing_done = true;
break;
case LZX_BLOCKTYPE_UNCOMPRESSED:
}
}
if (e8_preprocessing_done)
- undo_call_insn_preprocessing(uncompressed_data, uncompressed_len);
+ undo_call_insn_preprocessing(uncompressed_data, uncompressed_size);
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)
+static void
+lzx_free_decompressor(void *_ctx)
{
- return wimlib_lzx_decompress2(compressed_data, compressed_len,
- uncompressed_data, uncompressed_len,
- 32768);
+ struct lzx_decompressor *ctx = _ctx;
+
+ FREE(ctx);
}
+
+static int
+lzx_create_decompressor(size_t max_window_size,
+ const struct wimlib_decompressor_params_header *params,
+ void **ctx_ret)
+{
+ struct lzx_decompressor *ctx;
+
+ if (!lzx_window_size_valid(max_window_size))
+ return WIMLIB_ERR_INVALID_PARAM;
+
+ ctx = MALLOC(sizeof(struct lzx_decompressor));
+ if (ctx == NULL)
+ return WIMLIB_ERR_NOMEM;
+
+ ctx->max_window_size = max_window_size;
+ ctx->num_main_syms = lzx_get_num_main_syms(max_window_size);
+
+ *ctx_ret = ctx;
+ return 0;
+}
+
+const struct decompressor_ops lzx_decompressor_ops = {
+ .create_decompressor = lzx_create_decompressor,
+ .decompress = lzx_decompress,
+ .free_decompressor = lzx_free_decompressor,
+};
git://wimlib.net / wimlib / blobdiff