for #319, add signal to write config to file.

@@ -1421,6 +1421,13 @@ int SrsConfig::parse_options(int argc, char** argv)
     return ret;
 }
 
+int SrsConfig::persistence()
+{
+    int ret = ERROR_SUCCESS;
+    // TODO: FIXME: implements it.
+    return ret;
+}
+
 string SrsConfig::config()
 {
     return config_file;

@@ -288,6 +288,10 @@ public:
      */
     virtual int parse_options(int argc, char** argv);
     /**
+     * persistence current config to file.
+     */
+    virtual int persistence();
+    /**
      * get the config file path.
      */
     virtual std::string config();

@@ -50,7 +50,13 @@ using namespace std;
 #include <srs_core_mem_watch.hpp>
 
 // signal defines.
-#define SIGNAL_RELOAD SIGHUP
+// reload the config file and apply new config.
+#define SRS_SIGNAL_RELOAD SIGHUP
+// terminate the srs with dispose to detect memory leak for gmp.
+#define SRS_SIGNAL_DISPOSE SIGUSR2
+// persistence the config in memory to config file.
+// @see https://github.com/simple-rtmp-server/srs/issues/319#issuecomment-134993922
+#define SRS_SIGNAL_PERSISTENCE_CONFIG SIGUSR1
 
 // system interval in ms,
 // all resolution times should be times togother,
@@ -419,7 +425,7 @@ int SrsSignalManager::start()
     sa.sa_handler = SrsSignalManager::sig_catcher;
     sigemptyset(&sa.sa_mask);
     sa.sa_flags = 0;
-    sigaction(SIGNAL_RELOAD, &sa, NULL);
+    sigaction(SRS_SIGNAL_RELOAD, &sa, NULL);
     
     sa.sa_handler = SrsSignalManager::sig_catcher;
     sigemptyset(&sa.sa_mask);
@@ -434,7 +440,12 @@ int SrsSignalManager::start()
     sa.sa_handler = SrsSignalManager::sig_catcher;
     sigemptyset(&sa.sa_mask);
     sa.sa_flags = 0;
-    sigaction(SIGUSR2, &sa, NULL);
+    sigaction(SRS_SIGNAL_DISPOSE, &sa, NULL);
+    
+    sa.sa_handler = SrsSignalManager::sig_catcher;
+    sigemptyset(&sa.sa_mask);
+    sa.sa_flags = 0;
+    sigaction(SRS_SIGNAL_PERSISTENCE_CONFIG, &sa, NULL);
     
     srs_trace("signal installed");
     
@@ -481,6 +492,7 @@ ISrsServerCycle::~ISrsServerCycle()
 SrsServer::SrsServer()
 {
     signal_reload = false;
+    signal_persistence_config = false;
     signal_gmc_stop = false;
     signal_gracefully_quit = false;
     pid_fd = -1;
@@ -905,11 +917,16 @@ void SrsServer::remove(SrsConnection* conn)
 
 void SrsServer::on_signal(int signo)
 {
-    if (signo == SIGNAL_RELOAD) {
+    if (signo == SRS_SIGNAL_RELOAD) {
         signal_reload = true;
         return;
     }
     
+    if (signo == SRS_SIGNAL_PERSISTENCE_CONFIG) {
+        signal_persistence_config = true;
+        return;
+    }
+    
     if (signo == SIGINT || signo == SIGUSR2) {
 #ifdef SRS_AUTO_GPERF_MC
         srs_trace("gmc is on, main cycle will terminate normally.");
@@ -986,7 +1003,7 @@ int SrsServer::do_cycle()
             // do reload the config.
             if (signal_reload) {
                 signal_reload = false;
-                srs_info("get signal reload, to reload the config.");
+                srs_info("get signal to reload the config.");
                 
                 if ((ret = _srs_config->reload()) != ERROR_SUCCESS) {
                     srs_error("reload config failed. ret=%d", ret);
@@ -995,6 +1012,18 @@ int SrsServer::do_cycle()
                 srs_trace("reload config success.");
             }
             
+            // do persistence config to file.
+            if (signal_persistence_config) {
+                signal_persistence_config = false;
+                srs_info("get signal to persistence config to file.");
+                
+                if ((ret = _srs_config->persistence()) != ERROR_SUCCESS) {
+                    srs_error("persistence config to file failed. ret=%d", ret);
+                    return ret;
+                }
+                srs_trace("persistence config to file success.");
+            }
+            
             // notice the stream sources to cycle.
             if ((ret = SrsSource::cycle_all()) != ERROR_SUCCESS) {
                 return ret;

@@ -275,6 +275,7 @@ private:
     * user send the signal, convert to variable.
     */
     bool signal_reload;
+    bool signal_persistence_config;
     bool signal_gmc_stop;
     bool signal_gracefully_quit;
 public: