From 1cbdb69dffaa0a649b762b84d5a485e68f5188f6 Mon Sep 17 00:00:00 2001
From: "Matthias P. Braendli" <matthias.braendli@mpb.li>
Date: Mon, 25 Sep 2017 10:01:26 +0200
Subject: zmq2edi: automatically reconnect zmq socket if no data in 30s

---
 src/zmq2edi/zmq2edi.cpp | 114 +++++++++++++++++++++++++++---------------------
 1 file changed, 65 insertions(+), 49 deletions(-)

(limited to 'src/zmq2edi')

diff --git a/src/zmq2edi/zmq2edi.cpp b/src/zmq2edi/zmq2edi.cpp
index a1269a9..2216c85 100644
--- a/src/zmq2edi/zmq2edi.cpp
+++ b/src/zmq2edi/zmq2edi.cpp
@@ -235,77 +235,93 @@ int start(int argc, char **argv)
 
     const char* source_url = argv[optind];
 
-    etiLog.level(info) << "Opening ZMQ input: " << source_url;
     zmq::context_t zmq_ctx(1);
-    zmq::socket_t zmq_sock(zmq_ctx, ZMQ_SUB);
-
-    zmq_sock.connect(source_url);
-    zmq_sock.setsockopt(ZMQ_SUBSCRIBE, NULL, 0); // subscribe to all messages
 
     etiLog.level(info) << "Entering main loop";
     size_t frame_count = 0;
-    size_t error_count = 0;
-    while (error_count < 10)
-    {
-        zmq::message_t incoming;
-        zmq_sock.recv(&incoming);
-
-        zmq_dab_message_t* dab_msg = (zmq_dab_message_t*)incoming.data();
 
-        if (dab_msg->version != 1) {
-            etiLog.level(error) << "ZeroMQ wrong packet version " << dab_msg->version;
-            error_count++;
-        }
+    while (true) {
+        size_t error_count = 0;
 
-        int offset = sizeof(dab_msg->version) +
-            NUM_FRAMES_PER_ZMQ_MESSAGE * sizeof(*dab_msg->buflen);
+        etiLog.level(info) << "Opening ZMQ input: " << source_url;
 
-        std::list<std::pair<std::vector<uint8_t>, metadata_t> > all_frames;
+        zmq::socket_t zmq_sock(zmq_ctx, ZMQ_SUB);
+        zmq_sock.connect(source_url);
+        zmq_sock.setsockopt(ZMQ_SUBSCRIBE, NULL, 0); // subscribe to all messages
 
-        for (int i = 0; i < NUM_FRAMES_PER_ZMQ_MESSAGE; i++) {
-            if (dab_msg->buflen[i] <= 0 ||
-                dab_msg->buflen[i] > 6144)
-            {
-                etiLog.level(error) << "ZeroMQ buffer " << i << " has invalid length " <<
-                    dab_msg->buflen[i];
+        while (error_count < 10)
+        {
+            zmq::message_t incoming;
+            zmq::pollitem_t items[1];
+            items[0].socket = zmq_sock;
+            items[0].events = ZMQ_POLLIN;
+            const long timeout_ms = 3000;
+            const int num_events = zmq::poll(items, 1, timeout_ms);
+            if (num_events == 0) { // timeout
                 error_count++;
             }
             else {
-                std::vector<uint8_t> buf(6144, 0x55);
+                // Event received: recv will not block
+                zmq_sock.recv(&incoming);
 
-                const int framesize = dab_msg->buflen[i];
+                zmq_dab_message_t* dab_msg = (zmq_dab_message_t*)incoming.data();
 
-                memcpy(&buf.front(),
-                        ((uint8_t*)incoming.data()) + offset,
-                        framesize);
+                if (dab_msg->version != 1) {
+                    etiLog.level(error) << "ZeroMQ wrong packet version " << dab_msg->version;
+                    error_count++;
+                }
 
-                all_frames.emplace_back(
-                        std::piecewise_construct,
-                        std::make_tuple(std::move(buf)),
-                        std::make_tuple());
+                int offset = sizeof(dab_msg->version) +
+                    NUM_FRAMES_PER_ZMQ_MESSAGE * sizeof(*dab_msg->buflen);
 
-                offset += framesize;
-            }
-        }
+                std::list<std::pair<std::vector<uint8_t>, metadata_t> > all_frames;
+
+                for (int i = 0; i < NUM_FRAMES_PER_ZMQ_MESSAGE; i++) {
+                    if (dab_msg->buflen[i] <= 0 ||
+                            dab_msg->buflen[i] > 6144)
+                    {
+                        etiLog.level(error) << "ZeroMQ buffer " << i << " has invalid length " <<
+                            dab_msg->buflen[i];
+                        error_count++;
+                    }
+                    else {
+                        std::vector<uint8_t> buf(6144, 0x55);
 
-        for (auto &f : all_frames) {
-            size_t consumed_bytes = 0;
+                        const int framesize = dab_msg->buflen[i];
 
-            f.second = get_md_one_frame(
-                    static_cast<uint8_t*>(incoming.data()) + offset,
-                    incoming.size() - offset,
-                    &consumed_bytes);
+                        memcpy(&buf.front(),
+                                ((uint8_t*)incoming.data()) + offset,
+                                framesize);
 
-            offset += consumed_bytes;
-        }
+                        all_frames.emplace_back(
+                                std::piecewise_construct,
+                                std::make_tuple(std::move(buf)),
+                                std::make_tuple());
 
-        for (auto &f : all_frames) {
-            edisender.push_frame(f);
-            frame_count++;
+                        offset += framesize;
+                    }
+                }
+
+                for (auto &f : all_frames) {
+                    size_t consumed_bytes = 0;
+
+                    f.second = get_md_one_frame(
+                            static_cast<uint8_t*>(incoming.data()) + offset,
+                            incoming.size() - offset,
+                            &consumed_bytes);
+
+                    offset += consumed_bytes;
+                }
+
+                for (auto &f : all_frames) {
+                    edisender.push_frame(f);
+                    frame_count++;
+                }
+            }
         }
     }
 
-    return error_count > 0 ? 2 : 0;
+    return 0;
 }
 
 int main(int argc, char **argv)
-- 
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