X-Git-Url: https://wimlib.net/git/?a=blobdiff_plain;f=src%2Fxpress-decompress.c;h=431563b6a2de4c4c0b46fc6a3bce1b2bceea4644;hb=f3581db5c61c2cb180f77784feaa2e247956dd81;hp=1ab81e3192ea72de6e15c4a56d1fc7d76c014439;hpb=67c5f2c5954d07c25f57b6d9aedb73fb3720ec0b;p=wimlib

diff --git a/src/xpress-decompress.c b/src/xpress-decompress.c
index 1ab81e31..431563b6 100644
--- a/src/xpress-decompress.c
+++ b/src/xpress-decompress.c
@@ -89,12 +89,8 @@ xpress_decode_match(unsigned sym, input_idx_t window_pos,
 		    input_idx_t window_len, u8 window[restrict],
 		    struct input_bitstream * restrict istream)
 {
-
-	u8 len_hdr;
-	u8 offset_bsr;
-	u8 *match_dest;
-	u8 *match_src;
-	unsigned i;
+	unsigned len_hdr;
+	unsigned offset_bsr;
 	unsigned match_len;
 	unsigned match_offset;
 
@@ -119,21 +115,14 @@ xpress_decode_match(unsigned sym, input_idx_t window_pos,
 	}
 	match_len += XPRESS_MIN_MATCH_LEN;
 
-
-	/* Verify the match is in bounds, then copy its data to the current
-	 * position.  */
-
-	if (window_pos + match_len > window_len)
+	if (unlikely(match_len > window_len - window_pos))
 		return -1;
 
-	if (match_offset > window_pos)
+	if (unlikely(match_offset > window_pos))
 		return -1;
 
-	match_dest = window + window_pos;
-	match_src = match_dest - match_offset;
-
-	for (i = 0; i < match_len; i++)
-		match_dest[i] = match_src[i];
+	lz_copy(&window[window_pos], match_len, match_offset,
+		&window[window_len]);
 
 	return match_len;
 }
@@ -144,7 +133,6 @@ static int
 xpress_lz_decode(struct input_bitstream * restrict istream,
 		 u8 uncompressed_data[restrict],
 		 unsigned uncompressed_len,
-		 const u8 lens[restrict],
 		 const u16 decode_table[restrict])
 {
 	input_idx_t curpos;
@@ -157,8 +145,7 @@ xpress_lz_decode(struct input_bitstream * restrict istream,
 		bitstream_ensure_bits(istream, 16);
 
 		sym = read_huffsym(istream, decode_table,
-				   XPRESS_NUM_SYMBOLS, XPRESS_TABLEBITS,
-				   XPRESS_MAX_CODEWORD_LEN);
+				   XPRESS_TABLEBITS, XPRESS_MAX_CODEWORD_LEN);
 		if (sym < XPRESS_NUM_CHARS) {
 			/* Literal  */
 			uncompressed_data[curpos] = sym;
@@ -211,7 +198,7 @@ xpress_decompress(const void *compressed_data, size_t compressed_size,
 			     compressed_size - XPRESS_NUM_SYMBOLS / 2);
 
 	return xpress_lz_decode(&istream, uncompressed_data,
-				uncompressed_size, lens, decode_table);
+				uncompressed_size, decode_table);
 }
 
 const struct decompressor_ops xpress_decompressor_ops = {