indeo3: Fix null ptr dereference

[ffmpeg] / libavcodec / j2kdec.c

diff --git a/libavcodec/j2kdec.c b/libavcodec/j2kdec.c
index 01a1e2e39989d76f44fb7d26d69ad1e385ee4e75..1f4acc53fdd183ee53e64ba82eadea190cb97c3f 100644 (file)
--- a/libavcodec/j2kdec.c
+++ b/libavcodec/j2kdec.c
@@ -64,9 +64,9 @@ typedef struct {
     J2kCodingStyle codsty[4];
     J2kQuantStyle  qntsty[4];
 
-    uint8_t *buf_start;
-    uint8_t *buf;
-    uint8_t *buf_end;
+    const uint8_t *buf_start;
+    const uint8_t *buf;
+    const uint8_t *buf_end;
     int bit_index;
 
     int16_t curtileno;
@@ -227,7 +227,7 @@ static int get_siz(J2kDecoderContext *s)
         uint8_t x = bytestream_get_byte(&s->buf);
         s->cbps[i] = (x & 0x7f) + 1;
         s->precision = FFMAX(s->cbps[i], s->precision);
-        s->sgnd[i] = (x & 0x80) == 1;
+        s->sgnd[i] = !!(x & 0x80);
         s->cdx[i] = bytestream_get_byte(&s->buf);
         s->cdy[i] = bytestream_get_byte(&s->buf);
     }
@@ -903,13 +903,15 @@ static int decode_codestream(J2kDecoderContext *s)
 
     for (;;){
         int marker, len, ret = 0;
-        uint8_t *oldbuf;
+        const uint8_t *oldbuf;
         if (s->buf_end - s->buf < 2){
             av_log(s->avctx, AV_LOG_ERROR, "Missing EOC\n");
             break;
         }
 
         marker = bytestream_get_be16(&s->buf);
+        if(s->avctx->debug & FF_DEBUG_STARTCODE)
+            av_log(s->avctx, AV_LOG_DEBUG, "marker 0x%.4X at pos 0x%x\n", marker, s->buf - s->buf_start - 4);
         oldbuf = s->buf;
 
         if (marker == J2K_SOD){