lavf/avio: add ffurl_accept and ffurl_handshake

Signed-off-by: Stephan Holljes <klaxa1337@googlemail.com>

libavformat/avio.c

@@ -211,6 +211,26 @@ int ffurl_connect(URLContext *uc, AVDictionary **options)
     return 0;
 }
 
+int ffurl_accept(URLContext *s, URLContext **c)
+{
+    av_assert0(!*c);
+    if (s->prot->url_accept)
+        return s->prot->url_accept(s, c);
+    return AVERROR(EBADF);
+}
+
+int ffurl_handshake(URLContext *c)
+{
+    int ret;
+    if (c->prot->url_handshake) {
+        ret = c->prot->url_handshake(c);
+        if (ret)
+            return ret;
+    }
+    c->is_connected = 1;
+    return 0;
+}
+
 #define URL_SCHEME_CHARS                        \
     "abcdefghijklmnopqrstuvwxyz"                \
     "ABCDEFGHIJKLMNOPQRSTUVWXYZ"                \

libavformat/url.h

@@ -58,6 +58,8 @@ typedef struct URLProtocol {
      * for those nested protocols.
      */
     int     (*url_open2)(URLContext *h, const char *url, int flags, AVDictionary **options);
+    int     (*url_accept)(URLContext *s, URLContext **c);
+    int     (*url_handshake)(URLContext *c);
 
     /**
      * Read data from the protocol.
@@ -139,6 +141,29 @@ int ffurl_connect(URLContext *uc, AVDictionary **options);
 int ffurl_open(URLContext **puc, const char *filename, int flags,
                const AVIOInterruptCB *int_cb, AVDictionary **options);
 
+/**
+ * Accept an URLContext c on an URLContext s
+ *
+ * @param  s server context
+ * @param  c client context, must be unallocated.
+ * @return >= 0 on success, ff_neterrno() on failure.
+ */
+int ffurl_accept(URLContext *s, URLContext **c);
+
+/**
+ * Perform one step of the protocol handshake to accept a new client.
+ * See avio_handshake() for details.
+ * Implementations should try to return decreasing values.
+ * If the protocol uses an underlying protocol, the underlying handshake is
+ * usually the first step, and the return value can be:
+ * (largest value for this protocol) + (return value from other protocol)
+ *
+ * @param  c the client context
+ * @return >= 0 on success or a negative value corresponding
+ *         to an AVERROR code on failure
+ */
+int ffurl_handshake(URLContext *c);
+
 /**
  * Read up to size bytes from the resource accessed by h, and store
  * the read bytes in buf.