X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=libavcodec%2Flzw.c;h=fae5687ab7af48a524061bad74c46427fc71d393;hb=51d8725a6e4c7f989d6f0f38b59cb54a2d72846c;hp=aa886910bea86f087974babbbbf4d5b105f6af18;hpb=9a58234feaae8b387b7a7e41b643ec619534d26a;p=ffmpeg

diff --git a/libavcodec/lzw.c b/libavcodec/lzw.c
index aa886910bea..fae5687ab7a 100644
--- a/libavcodec/lzw.c
+++ b/libavcodec/lzw.c
@@ -3,20 +3,20 @@
  * Copyright (c) 2003 Fabrice Bellard
  * Copyright (c) 2006 Konstantin Shishkov
  *
- * This file is part of FFmpeg.
+ * This file is part of Libav.
  *
- * FFmpeg is free software; you can redistribute it and/or
+ * Libav is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
  * License as published by the Free Software Foundation; either
  * version 2.1 of the License, or (at your option) any later version.
  *
- * FFmpeg is distributed in the hope that it will be useful,
+ * Libav is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with FFmpeg; if not, write to the Free Software
+ * License along with Libav; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
@@ -24,11 +24,13 @@
  * @file
  * @brief LZW decoding routines
  * @author Fabrice Bellard
- * Modified for use in TIFF by Konstantin Shishkov
+ * @author modified for use in TIFF by Konstantin Shishkov
  */
 
 #include "avcodec.h"
+#include "bytestream.h"
 #include "lzw.h"
+#include "libavutil/mem.h"
 
 #define LZW_MAXBITS                 12
 #define LZW_SIZTABLE                (1<<LZW_MAXBITS)
@@ -42,7 +44,7 @@ static const uint16_t mask[17] =
 };
 
 struct LZWState {
-    const uint8_t *pbuf, *ebuf;
+    GetByteContext gb;
     int bbits;
     unsigned int bbuf;
 
@@ -72,9 +74,9 @@ static int lzw_get_code(struct LZWState * s)
     if(s->mode == FF_LZW_GIF) {
         while (s->bbits < s->cursize) {
             if (!s->bs) {
-                s->bs = *s->pbuf++;
+                s->bs = bytestream2_get_byte(&s->gb);
             }
-            s->bbuf |= (*s->pbuf++) << s->bbits;
+            s->bbuf |= bytestream2_get_byte(&s->gb) << s->bbits;
             s->bbits += 8;
             s->bs--;
         }
@@ -82,7 +84,7 @@ static int lzw_get_code(struct LZWState * s)
         s->bbuf >>= s->cursize;
     } else { // TIFF
         while (s->bbits < s->cursize) {
-            s->bbuf = (s->bbuf << 8) | (*s->pbuf++);
+            s->bbuf = (s->bbuf << 8) | bytestream2_get_byte(&s->gb);
             s->bbits += 8;
         }
         c = s->bbuf >> (s->bbits - s->cursize);
@@ -91,9 +93,10 @@ static int lzw_get_code(struct LZWState * s)
     return c & s->curmask;
 }
 
-const uint8_t* ff_lzw_cur_ptr(LZWState *p)
+int ff_lzw_size_read(LZWState *p)
 {
-    return ((struct LZWState*)p)->pbuf;
+    struct LZWState *s = p;
+    return bytestream2_tell(&s->gb);
 }
 
 void ff_lzw_decode_tail(LZWState *p)
@@ -101,12 +104,12 @@ void ff_lzw_decode_tail(LZWState *p)
     struct LZWState *s = (struct LZWState *)p;
 
     if(s->mode == FF_LZW_GIF) {
-        while(s->pbuf < s->ebuf && s->bs>0){
-            s->pbuf += s->bs;
-            s->bs = *s->pbuf++;
+        while (s->bs > 0 && bytestream2_get_bytes_left(&s->gb)) {
+            bytestream2_skip(&s->gb, s->bs);
+            s->bs = bytestream2_get_byte(&s->gb);
         }
     }else
-        s->pbuf= s->ebuf;
+        bytestream2_skip(&s->gb, bytestream2_get_bytes_left(&s->gb));
 }
 
 av_cold void ff_lzw_decode_open(LZWState **p)
@@ -134,8 +137,7 @@ int ff_lzw_decode_init(LZWState *p, int csize, const uint8_t *buf, int buf_size,
     if(csize < 1 || csize >= LZW_MAXBITS)
         return -1;
     /* read buffer */
-    s->pbuf = buf;
-    s->ebuf = s->pbuf + buf_size;
+    bytestream2_init(&s->gb, buf, buf_size);
     s->bbuf = 0;
     s->bbits = 0;
     s->bs = 0;