Fixed passing the chunk size by transmit to SRTO_PAYLOADSIZE option

apps/srt-live-transmit.cpp

@@ -82,10 +82,6 @@
 #include <srt.h>
 #include <logging.h>
 
-// The length of the SRT payload used in srt_recvmsg call.
-// So far, this function must be used and up to this length of payload.
-const size_t DEFAULT_CHUNK = 1316;
-
 using namespace std;
 
 
@@ -240,7 +236,14 @@ int main( int argc, char** argv )
     int timeout = stoi(Option("30", "t", "to", "timeout"), 0, 0);
     size_t chunk = stoul(Option("0", "c", "chunk"), 0, 0);
     if ( chunk == 0 )
-        chunk = DEFAULT_CHUNK;
+    {
+        chunk = SRT_LIVE_DEF_PLSIZE;
+    }
+    else
+    {
+        transmit_chunk_size = chunk;
+    }
+
     size_t bandwidth = stoul(Option("0", "b", "bandwidth", "bitrate"), 0, 0);
     transmit_bw_report = stoul(Option("0", "r", "report", "bandwidth-report", "bitrate-report"), 0, 0);
     transmit_verbose = Option("no", "v", "verbose") != "no";
@@ -286,6 +289,7 @@ int main( int argc, char** argv )
         }
     }
 
+
 #ifdef WIN32
 #define alarm(argument) (void)0
 #else

common/transmitbase.hpp

@@ -12,6 +12,7 @@ extern volatile bool transmit_throw_on_interrupt;
 extern int transmit_bw_report;
 extern unsigned transmit_stats_report;
 extern std::ostream* transmit_cverb;
+extern size_t transmit_chunk_size;
 
 static const struct VerboseLogNoEol { VerboseLogNoEol() {} } VerbNoEOL;
 

common/transmitmedia.cpp

@@ -24,6 +24,7 @@ std::ostream* transmit_cverb = nullptr;
 volatile bool transmit_throw_on_interrupt = false;
 int transmit_bw_report = 0;
 unsigned transmit_stats_report = 0;
+size_t transmit_chunk_size = SRT_LIVE_DEF_PLSIZE;
 
 class FileSource: public Source
 {
@@ -168,9 +169,22 @@ void SrtCommon::InitParameters(string host, map<string,string> par)
         par.erase("port");
     }
 
+    // That's kinda clumsy, but it must rely on the defaults.
+    // Default mode is live, so check if the file mode was enforced
+    if (par.count("transtype") == 0 || par["transtype"] != "file")
+    {
+        // If the Live chunk size was nondefault, enforce the size.
+        if (transmit_chunk_size != SRT_LIVE_DEF_PLSIZE)
+        {
+            if (transmit_chunk_size > SRT_LIVE_MAX_PLSIZE)
+                throw std::runtime_error("Chunk size in live mode exceeds 1456 bytes; this is not supported");
+
+            par["payloadsize"] = Sprint(transmit_chunk_size);
+        }
+    }
+
     // Assign the others here.
     m_options = par;
-
 }
 
 void SrtCommon::PrepareListener(string host, int port, int backlog)