Add srt caller mode and stream encryption support. (#4088)

Add srt caller mode and stream encryption support.
1. Support srt caller mode, realize srt proxy pull stream proxy push
stream;
url parameter format such as: srt://127.0.0.1:9000?streamid=#!
::r=live/test11
2. Support srt stream encrypted transmission in caller and listener
mode.

---------

Co-authored-by: xiongguangjie <xiong_panda@163.com>

src/Srt/SrtPlayerImp.h

@@ -0,0 +1,51 @@
+/*
+ * Copyright (c) 2016-present The ZLMediaKit project authors. All Rights Reserved.
+ *
+ * This file is part of ZLMediaKit(https://github.com/ZLMediaKit/ZLMediaKit).
+ *
+ * Use of this source code is governed by MIT-like license that can be found in the
+ * LICENSE file in the root of the source tree. All contributing project authors
+ * may be found in the AUTHORS file in the root of the source tree.
+ */
+
+#ifndef ZLMEDIAKIT_SRtPLAYERIMP_H
+#define ZLMEDIAKIT_SRtPLAYERIMP_H
+
+#include "SrtPlayer.h"
+
+namespace mediakit {
+
+class SrtPlayerImp
+    : public PlayerImp<SrtPlayer, PlayerBase>
+    , private TrackListener {
+public:
+    using Ptr = std::shared_ptr<SrtPlayerImp>;
+    using Super = PlayerImp<SrtPlayer, PlayerBase>;
+
+    SrtPlayerImp(const toolkit::EventPoller::Ptr &poller) : Super(poller) {}
+    ~SrtPlayerImp() override { DebugL; }
+
+private:
+    //// SrtPlayer override////
+	void onSRTData(SRT::DataPacket::Ptr pkt) override;
+
+    //// PlayerBase override////
+    void onPlayResult(const toolkit::SockException &ex) override;
+    std::vector<Track::Ptr> getTracks(bool ready = true) const override;
+
+private:
+    //// TrackListener override////
+    bool addTrack(const Track::Ptr &track) override { return true; }
+    void addTrackCompleted() override;
+
+private:
+    // for player
+    DecoderImp::Ptr _decoder;
+    MediaSinkInterface::Ptr _demuxer;
+
+    // for pusher
+    TSMediaSource::RingType::RingReader::Ptr _ts_reader;
+};
+
+} /* namespace mediakit */
+#endif /* ZLMEDIAKIT_SRtPLAYERIMP_H */