Fix reading > 16 bits from bitstream

[wimlib] / include / wimlib / compress.h

diff --git a/include/wimlib/compress.h b/include/wimlib/compress.h
index f3ce6e2deb834921589d14593084c5829819e3b5..fcd3c4119f16c9e37298a87760ddbd99b56186b3 100644 (file)
--- a/include/wimlib/compress.h
+++ b/include/wimlib/compress.h
@@ -7,26 +7,24 @@
 #ifndef _WIMLIB_COMPRESS_H
 #define _WIMLIB_COMPRESS_H
 
-#include "wimlib/endianness.h"
 #include "wimlib/types.h"
 
-typedef u16 output_bitbuf_t;
-
 /* Variable type that can represent all possible window positions.  */
-typedef u32 freq_t;
 #ifndef INPUT_IDX_T_DEFINED
 #define INPUT_IDX_T_DEFINED
 typedef u32 input_idx_t;
 #endif
 
-/* Structure to keep track of the current position in the compressed output. */
+/* Structure to keep track of the current state sending bits and bytes to the
+ * compressed output buffer.  */
 struct output_bitstream {
 
-       /* A variable to buffer writing bits to the output and is flushed to the
-        * compressed output when full. */
-       output_bitbuf_t bitbuf;
+       /* Variable that holds up to 16 bits that haven't yet been flushed to
+        * the output.  */
+       u16 bitbuf;
 
-       /* Number of free bits in @bitbuf */
+       /* Number of free bits in @bitbuf; that is, 16 minus the number of valid
+        * bits in @bitbuf.  */
        unsigned free_bits;
 
        /* Pointer to the start of the output buffer.  */
@@ -45,7 +43,7 @@ struct output_bitstream {
         */
        u8 *output;
 
-       /* Bytes remaining in @output buffer.  */
+       /* Number of bytes remaining in the @output buffer.  */
        input_idx_t bytes_remaining;
 
        /* Set to true if the buffer has been exhausted.  */
@@ -61,7 +59,7 @@ flush_output_bitstream(struct output_bitstream *ostream);
 
 extern void
 bitstream_put_bits(struct output_bitstream *ostream,
-                  output_bitbuf_t bits, unsigned num_bits);
+                  u32 bits, unsigned num_bits);
 
 extern void
 bitstream_put_byte(struct output_bitstream *ostream, u8 n);
@@ -69,6 +67,7 @@ bitstream_put_byte(struct output_bitstream *ostream, u8 n);
 struct lz_params {
        unsigned min_match;
        unsigned max_match;
+       unsigned max_offset;
        unsigned nice_match;
        unsigned good_match;
        unsigned max_chain_len;
@@ -80,17 +79,18 @@ typedef void (*lz_record_match_t)(unsigned len, unsigned offset, void *ctx);
 typedef void (*lz_record_literal_t)(u8 lit, void *ctx);
 
 extern void
-lz_analyze_block(const u8 window[],
+lz_analyze_block(const u8 window[restrict],
                 input_idx_t window_size,
                 lz_record_match_t record_match,
                 lz_record_literal_t record_literal,
                 void *record_ctx,
-                const struct lz_params *params);
+                const struct lz_params *params,
+                input_idx_t prev_tab[restrict]);
 
 extern void
 make_canonical_huffman_code(unsigned num_syms,
                            unsigned max_codeword_len,
-                           const freq_t freq_tab[restrict],
+                           const input_idx_t freq_tab[restrict],
                            u8 lens[restrict],
                            u16 codewords[restrict]);