avio: introduce avio_closep

doc/APIchanges

@@ -13,6 +13,9 @@ libavutil:     2011-04-18
 
 API changes, most recent first:
 
+2012-10-xx - xxxxxxx - lavf 54.18.0 - avio.h
+  Add avio_closep to complement avio_close.
+
 2012-10-xx - xxxxxxx - lavu 51.42.0 - pixfmt.h
   Rename PixelFormat to AVPixelFormat and all PIX_FMT_* to AV_PIX_FMT_*.
   To provide backwards compatibility, PixelFormat is now #defined as

libavformat/avio.h

@@ -353,9 +353,24 @@ int avio_open2(AVIOContext **s, const char *url, int flags,
  * resource.
  *
  * @return 0 on success, an AVERROR < 0 on error.
+ * @see avio_closep
  */
 int avio_close(AVIOContext *s);
 
+/**
+ * Close the resource accessed by the AVIOContext *s, free it
+ * and set the pointer pointing to it to NULL.
+ * This function can only be used if s was opened by avio_open().
+ *
+ * The internal buffer is automatically flushed before closing the
+ * resource.
+ *
+ * @return 0 on success, an AVERROR < 0 on error.
+ * @see avio_close
+ */
+int avio_closep(AVIOContext **s);
+
+
 /**
  * Open a write only memory stream.
  *

libavformat/aviobuf.c

@@ -768,6 +768,13 @@ int avio_close(AVIOContext *s)
     return ffurl_close(h);
 }
 
+int avio_closep(AVIOContext **s)
+{
+    int ret = avio_close(*s);
+    *s = NULL;
+    return ret;
+}
+
 int avio_printf(AVIOContext *s, const char *fmt, ...)
 {
     va_list ap;

libavformat/version.h

@@ -30,8 +30,8 @@
 #include "libavutil/avutil.h"
 
 #define LIBAVFORMAT_VERSION_MAJOR 54
-#define LIBAVFORMAT_VERSION_MINOR 17
-#define LIBAVFORMAT_VERSION_MICRO  3
+#define LIBAVFORMAT_VERSION_MINOR 18
+#define LIBAVFORMAT_VERSION_MICRO  0
 
 #define LIBAVFORMAT_VERSION_INT AV_VERSION_INT(LIBAVFORMAT_VERSION_MAJOR, \
                                                LIBAVFORMAT_VERSION_MINOR, \