avio: Introduce avio_read_to_bprint(avioctx, bp, max_size)

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

doc/APIchanges

@@ -15,6 +15,9 @@ libavutil:     2012-10-22
 
 API changes, most recent first:
 
+2014-07-23 - XXXXXXX - lavf 55.49.100 - avio.h
+  Add avio_read_to_bprint()
+
 2014-07-14 - 62227a7 - lavf 55.47.100 - avformat.h
   Add av_stream_get_parser()
 

libavformat/avio.h

@@ -31,6 +31,7 @@
 #include "libavutil/common.h"
 #include "libavutil/dict.h"
 #include "libavutil/log.h"
+#include "libavutil/bprint.h"
 
 #include "libavformat/version.h"
 
@@ -500,4 +501,12 @@ int     avio_pause(AVIOContext *h, int pause);
 int64_t avio_seek_time(AVIOContext *h, int stream_index,
                        int64_t timestamp, int flags);
 
+/**
+ * Read contents of h into print buffer, up to max_size bytes, or up to EOF.
+ *
+ * @return 0 for success (max_size bytes read or EOF reached), negative error
+ * code otherwise
+ */
+int avio_read_to_bprint(AVIOContext *h, AVBPrint *pb, size_t max_size);
+
 #endif /* AVFORMAT_AVIO_H */

libavformat/aviobuf.c

@@ -953,6 +953,24 @@ int64_t avio_seek_time(AVIOContext *s, int stream_index,
     return ret;
 }
 
+int avio_read_to_bprint(AVIOContext *h, AVBPrint *pb, size_t max_size)
+{
+    int ret;
+    char buf[1024];
+    while (max_size) {
+        ret = avio_read(h, buf, FFMIN(max_size, sizeof(buf)));
+        if (ret == AVERROR_EOF)
+            return 0;
+        if (ret <= 0)
+            return ret;
+        av_bprint_append_data(pb, buf, ret);
+        if (!av_bprint_is_complete(pb))
+            return AVERROR(ENOMEM);
+        max_size -= ret;
+    }
+    return 0;
+}
+
 /* output in a dynamic buffer */
 
 typedef struct DynBuffer {

libavformat/version.h

@@ -30,8 +30,8 @@
 #include "libavutil/version.h"
 
 #define LIBAVFORMAT_VERSION_MAJOR 55
-#define LIBAVFORMAT_VERSION_MINOR 48
-#define LIBAVFORMAT_VERSION_MICRO 101
+#define LIBAVFORMAT_VERSION_MINOR 49
+#define LIBAVFORMAT_VERSION_MICRO 100
 
 #define LIBAVFORMAT_VERSION_INT AV_VERSION_INT(LIBAVFORMAT_VERSION_MAJOR, \
                                                LIBAVFORMAT_VERSION_MINOR, \