avformat/argo_asf: add ASF_MIN_BUFFER_SIZE #define

For future use by the argo_brp demuxer

Signed-off-by: Zane van Iperen <zane@zanevaniperen.com>

libavformat/argo_asf.c

@@ -182,7 +182,7 @@ static int argo_asf_read_header(AVFormatContext *s)
     AVIOContext *pb = s->pb;
     AVStream *st;
     ArgoASFDemuxContext *asf = s->priv_data;
-    uint8_t buf[FFMAX(ASF_FILE_HEADER_SIZE, ASF_CHUNK_HEADER_SIZE)];
+    uint8_t buf[ASF_MIN_BUFFER_SIZE];
 
     if (!(st = avformat_new_stream(s, NULL)))
         return AVERROR(ENOMEM);

libavformat/argo_asf.h

@@ -24,11 +24,13 @@
 #define AVFORMAT_ARGO_ASF_H
 
 #include <stdint.h>
+#include "libavutil/common.h"
 
 #define ASF_TAG                 MKTAG('A', 'S', 'F', '\0')
 #define ASF_FILE_HEADER_SIZE    24
 #define ASF_CHUNK_HEADER_SIZE   20
 #define ASF_SAMPLE_COUNT        32
+#define ASF_MIN_BUFFER_SIZE     FFMAX(ASF_FILE_HEADER_SIZE, ASF_CHUNK_HEADER_SIZE)
 
 typedef struct ArgoASFFileHeader {
     uint32_t    magic;          /*< Magic Number, {'A', 'S', 'F', '\0'} */