Rework STI/EDI/UDP multicast input group join

2 files changed, 23 insertions, 2 deletions

diff --git a/doc/example.mux b/doc/example.mux
index 383a2ab..d53b789 100644
--- a/doc/example.mux
+++ b/doc/example.mux
@@ -215,6 +215,8 @@ subchannels {
         ;inputuri "udp://:9001"
         ; Multicast UDP input:
         ;inputuri "udp://@239.10.0.1:9001"
+        ; Multicast UDP input with local interface (192.168.0.10) specification
+        ;inputuri "udp://192.168.0.10@239.10.0.1:9001"
 
         ; Two buffer-management types are available: prebuffering and timestamped.
         ; prebuffering will accumulate a few frames before it starts streaming, and each
diff --git a/src/input/Edi.cpp b/src/input/Edi.cpp
index 3838541..fc380d8 100644
--- a/src/input/Edi.cpp
+++ b/src/input/Edi.cpp
@@ -81,6 +81,7 @@ void Edi::open(const std::string& name)
 {
     const std::regex re_udp("udp://:([0-9]+)");
     const std::regex re_udp_multicast("udp://@([0-9.]+):([0-9]+)");
+    const std::regex re_udp_multicast_bindto("udp://([0-9.])+@([0-9.]+):([0-9]+)");
     const std::regex re_tcp("tcp://(.*):([0-9]+)");
 
     lock_guard<mutex> lock(m_mutex);
@@ -97,13 +98,31 @@ void Edi::open(const std::string& name)
         m_udp_sock.reinit(udp_port);
         m_udp_sock.setBlocking(false);
     }
+    else if (std::regex_match(name, m, re_udp_multicast_bindto)) {
+        const string bind_to = m[1].str();
+        const string multicast_address = m[2].str();
+        const int udp_port = std::stoi(m[3].str());
+
+        m_input_used = InputUsed::UDP;
+        if (IN_MULTICAST(ntohl(inet_addr(multicast_address.c_str())))) {
+            m_udp_sock.init_receive_multicast(udp_port, bind_to, multicast_address);
+        }
+        else {
+            throw runtime_error(string("Address ") + multicast_address + " is not a multicast address");
+        }
+        m_udp_sock.setBlocking(false);
+    }
     else if (std::regex_match(name, m, re_udp_multicast)) {
         const string multicast_address = m[1].str();
         const int udp_port = std::stoi(m[2].str());
         m_input_used = InputUsed::UDP;
-        m_udp_sock.reinit(udp_port);
+        if (IN_MULTICAST(ntohl(inet_addr(multicast_address.c_str())))) {
+            m_udp_sock.init_receive_multicast(udp_port, "0.0.0.0", multicast_address);
+        }
+        else {
+            throw runtime_error(string("Address ") + multicast_address + " is not a multicast address");
+        }
         m_udp_sock.setBlocking(false);
-        m_udp_sock.joinGroup(multicast_address.c_str());
     }
     else if (std::regex_match(name, m, re_tcp)) {
         m_input_used = InputUsed::TCP;