Add more EDI input improvements

1 files changed, 88 insertions, 0 deletions

diff --git a/lib/edi/common.hpp b/lib/edi/common.hpp
new file mode 100644
index 0000000..1433004
--- /dev/null
+++ b/lib/edi/common.hpp
@@ -0,0 +1,88 @@
+/*
+   Copyright (C) 2019
+   Matthias P. Braendli, matthias.braendli@mpb.li
+
+   http://opendigitalradio.org
+
+    This program is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License along
+    with this program; if not, write to the Free Software Foundation, Inc.,
+    51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+#pragma once
+
+#include "PFT.hpp"
+#include <functional>
+#include <map>
+#include <string>
+#include <vector>
+#include <cstddef>
+#include <ctime>
+
+namespace EdiDecoder {
+
+struct frame_timestamp_t {
+    uint32_t seconds = 0;
+    uint32_t utco = 0;
+
+    std::string to_string() const;
+    time_t to_unix_epoch() const;
+};
+
+struct decode_state_t {
+    decode_state_t(bool _complete, size_t _num_bytes_consumed) :
+        complete(_complete), num_bytes_consumed(_num_bytes_consumed) {}
+    bool complete;
+    size_t num_bytes_consumed;
+};
+
+/* The TagDispatcher takes care of decoding EDI, with or without PFT, and
+ * will call functions when TAGs are encountered.
+ *
+ * PF packets are handed over to the PFT decoder, which will in turn return
+ * AF packets. AF packets are directly dispatched to the TAG functions.
+ */
+class TagDispatcher {
+    public:
+        TagDispatcher(std::function<void()>&& af_packet_completed, bool verbose);
+
+        /* Push bytes into the decoder. The buf can contain more
+         * than a single packet. This is useful when reading from streams
+         * (files, TCP)
+         */
+        void push_bytes(const std::vector<uint8_t> &buf);
+
+        /* Push a complete packet into the decoder. Useful for UDP and other
+         * datagram-oriented protocols.
+         */
+        void push_packet(const std::vector<uint8_t> &buf);
+
+        /* Set the maximum delay in number of AF Packets before we
+         * abandon decoding a given pseq.
+         */
+        void setMaxDelay(int num_af_packets);
+
+        using tag_handler = std::function<bool(std::vector<uint8_t>, uint16_t)>;
+        void register_tag(const std::string& tag, tag_handler&& h);
+
+    private:
+        decode_state_t decode_afpacket(const std::vector<uint8_t> &input_data);
+        bool decode_tagpacket(const std::vector<uint8_t> &payload);
+
+        PFT::PFT m_pft;
+        uint16_t m_last_seq = 0;
+        std::vector<uint8_t> m_input_data;
+        std::map<std::string, tag_handler> m_handlers;
+        std::function<void()> m_af_packet_completed;
+};
+
+}