msrle: convert MS RLE decoding function to bytestream2.

Signed-off-by: Justin Ruggles <justin.ruggles@gmail.com>

libavcodec/aasc.c

@@ -34,17 +34,10 @@
 
 typedef struct AascContext {
     AVCodecContext *avctx;
+    GetByteContext gb;
     AVFrame frame;
 } AascContext;
 
-#define FETCH_NEXT_STREAM_BYTE() \
-    if (stream_ptr >= buf_size) \
-    { \
-      av_log(s->avctx, AV_LOG_ERROR, " AASC: stream ptr just went out of bounds (fetch)\n"); \
-      break; \
-    } \
-    stream_byte = buf[stream_ptr++];
-
 static av_cold int aasc_decode_init(AVCodecContext *avctx)
 {
     AascContext *s = avctx->priv_data;
@@ -84,7 +77,8 @@ static int aasc_decode_frame(AVCodecContext *avctx,
         }
         break;
     case 1:
-        ff_msrle_decode(avctx, (AVPicture*)&s->frame, 8, buf - 4, buf_size + 4);
+        bytestream2_init(&s->gb, buf - 4, buf_size + 4);
+        ff_msrle_decode(avctx, (AVPicture*)&s->frame, 8, &s->gb);
         break;
     default:
         av_log(avctx, AV_LOG_ERROR, "Unknown compression type %d\n", compr);

libavcodec/bmp.c

@@ -52,6 +52,7 @@ static int bmp_decode_frame(AVCodecContext *avctx,
     uint8_t *ptr;
     int dsize;
     const uint8_t *buf0 = buf;
+    GetByteContext gb;
 
     if(buf_size < 14){
         av_log(avctx, AV_LOG_ERROR, "buf size too small (%d)\n", buf_size);
@@ -265,7 +266,8 @@ static int bmp_decode_frame(AVCodecContext *avctx,
             p->data[0] += p->linesize[0] * (avctx->height - 1);
             p->linesize[0] = -p->linesize[0];
         }
-        ff_msrle_decode(avctx, (AVPicture*)p, depth, buf, dsize);
+        bytestream2_init(&gb, buf, dsize);
+        ff_msrle_decode(avctx, (AVPicture*)p, depth, &gb);
         if(height < 0){
             p->data[0] += p->linesize[0] * (avctx->height - 1);
             p->linesize[0] = -p->linesize[0];

libavcodec/msrle.c

@@ -40,6 +40,7 @@ typedef struct MsrleContext {
     AVCodecContext *avctx;
     AVFrame frame;
 
+    GetByteContext gb;
     const unsigned char *buf;
     int size;
 
@@ -123,7 +124,8 @@ static int msrle_decode_frame(AVCodecContext *avctx,
             ptr += s->frame.linesize[0];
         }
     } else {
-        ff_msrle_decode(avctx, (AVPicture*)&s->frame, avctx->bits_per_coded_sample, buf, buf_size);
+        bytestream2_init(&s->gb, buf, buf_size);
+        ff_msrle_decode(avctx, (AVPicture*)&s->frame, avctx->bits_per_coded_sample, &s->gb);
     }
 
     *data_size = sizeof(AVFrame);

libavcodec/msrledec.h

@@ -23,6 +23,7 @@
 #define AVCODEC_MSRLEDEC_H
 
 #include "avcodec.h"
+#include "bytestream.h"
 
 /**
  * Decode stream in MS RLE format into frame.
@@ -30,10 +31,9 @@
  * @param avctx     codec context
  * @param pic       destination frame
  * @param depth     bit depth
- * @param data      input stream
- * @param data_size input size
+ * @param gb        input bytestream context
  */
-int ff_msrle_decode(AVCodecContext *avctx, AVPicture *pic, int depth,
-                    const uint8_t* data, int data_size);
+int ff_msrle_decode(AVCodecContext *avctx, AVPicture *pic,
+                    int depth, GetByteContext *gb);
 
 #endif /* AVCODEC_MSRLEDEC_H */

libavcodec/tscc.c

@@ -58,6 +58,7 @@ typedef struct TsccContext {
     unsigned int decomp_size;
     // Decompression buffer
     unsigned char* decomp_buf;
+    GetByteContext gb;
     int height;
     z_stream zstream;
 
@@ -105,8 +106,11 @@ static int decode_frame(AVCodecContext *avctx, void *data, int *data_size, AVPac
     }
 
 
-    if(zret != Z_DATA_ERROR)
-        ff_msrle_decode(avctx, (AVPicture*)&c->pic, c->bpp, c->decomp_buf, c->decomp_size - c->zstream.avail_out);
+    if (zret != Z_DATA_ERROR) {
+        bytestream2_init(&c->gb, c->decomp_buf,
+                         c->decomp_size - c->zstream.avail_out);
+        ff_msrle_decode(avctx, (AVPicture*)&c->pic, c->bpp, &c->gb);
+    }
 
     /* make the palette available on the way out */
     if (c->avctx->pix_fmt == PIX_FMT_PAL8) {