]> wimlib.net Git - wimlib/blobdiff - src/xpress-decompress.c
compress_parallel.c: Determine physical memory on OS X
[wimlib] / src / xpress-decompress.c
index b71f6be23e1c6f8a502564fda9b29e966d33a5fa..c24a1e66d8d2c574e03897089cb3015f258b9252 100644 (file)
  *
  * Also, a caveat--- according to Microsoft's documentation for XPRESS,
  *
- *     "Some implementation of the decompression algorithm expect an extra
- *     symbol to mark the end of the data.  Specifically, some implementations
- *     fail during decompression if the Huffman symbol 256 is not found after
- *     the actual data."
+ *     "Some implementation of the decompression algorithm expect an extra
+ *     symbol to mark the end of the data.  Specifically, some implementations
+ *     fail during decompression if the Huffman symbol 256 is not found after
+ *     the actual data."
  *
  * This is the case for the implementation in WIMGAPI.  However, wimlib's
  * decompressor in this file currently does not care if this extra symbol is
@@ -70,7 +70,8 @@
 #endif
 
 #include "wimlib.h"
-#include "wimlib/decompress.h"
+#include "wimlib/decompressor_ops.h"
+#include "wimlib/decompress_common.h"
 #include "wimlib/xpress.h"
 
 /*
@@ -194,14 +195,11 @@ xpress_lz_decode(struct input_bitstream * restrict istream,
 }
 
 
-/* API function documented in wimlib.h  */
-WIMLIBAPI int
-wimlib_xpress_decompress(const void * const restrict _compressed_data,
-                        const unsigned compressed_len,
-                        void * const restrict uncompressed_data,
-                        const unsigned uncompressed_len)
+static int
+xpress_decompress(const void *compressed_data, size_t compressed_size,
+                 void *uncompressed_data, size_t uncompressed_size, void *_ctx)
 {
-       const u8 *compressed_data = _compressed_data;
+       const u8 *cdata = compressed_data;
        u8 lens[XPRESS_NUM_SYMBOLS];
        u8 *lens_p;
        u16 decode_table[(1 << XPRESS_TABLEBITS) + 2 * XPRESS_NUM_SYMBOLS]
@@ -211,13 +209,13 @@ wimlib_xpress_decompress(const void * const restrict _compressed_data,
        /* XPRESS uses only one Huffman code.  It contains 512 symbols, and the
         * code lengths of these symbols are given literally as 4-bit integers
         * in the first 256 bytes of the compressed data.  */
-       if (compressed_len < XPRESS_NUM_SYMBOLS / 2)
+       if (compressed_size < XPRESS_NUM_SYMBOLS / 2)
                return -1;
 
        lens_p = lens;
        for (unsigned i = 0; i < XPRESS_NUM_SYMBOLS / 2; i++) {
-               *lens_p++ = compressed_data[i] & 0xf;
-               *lens_p++ = compressed_data[i] >> 4;
+               *lens_p++ = cdata[i] & 0xf;
+               *lens_p++ = cdata[i] >> 4;
        }
 
        if (make_huffman_decode_table(decode_table, XPRESS_NUM_SYMBOLS,
@@ -225,9 +223,13 @@ wimlib_xpress_decompress(const void * const restrict _compressed_data,
                                      XPRESS_MAX_CODEWORD_LEN))
                return -1;
 
-       init_input_bitstream(&istream, compressed_data + XPRESS_NUM_SYMBOLS / 2,
-                            compressed_len - XPRESS_NUM_SYMBOLS / 2);
+       init_input_bitstream(&istream, cdata + XPRESS_NUM_SYMBOLS / 2,
+                            compressed_size - XPRESS_NUM_SYMBOLS / 2);
 
        return xpress_lz_decode(&istream, uncompressed_data,
-                               uncompressed_len, lens, decode_table);
+                               uncompressed_size, lens, decode_table);
 }
+
+const struct decompressor_ops xpress_decompressor_ops = {
+       .decompress = xpress_decompress,
+};