From 91aba16d98b97d5b2129f04f096d873c369f51b6 Mon Sep 17 00:00:00 2001
From: Jonathan Naylor <naylorjs@yahoo.com>
Date: Tue, 3 May 2016 23:01:49 +0100
Subject: [PATCH] Add daemonisation under Linux and other enhancements (from
 Simon G7RZU)

---
 Conf.cpp      |  8 ++++++++
 Conf.h        |  2 ++
 MMDVM.ini     |  1 +
 MMDVMHost.cpp | 55 +++++++++++++++++++++++++++++++++++++++++++--------
 4 files changed, 58 insertions(+), 8 deletions(-)

diff --git a/Conf.cpp b/Conf.cpp
index 93a6b28..7e7f6de 100644
--- a/Conf.cpp
+++ b/Conf.cpp
@@ -51,6 +51,7 @@ m_timeout(120U),
 m_duplex(true),
 m_modeHang(10U),
 m_display(),
+m_daemon(false),
 m_rxFrequency(0U),
 m_txFrequency(0U),
 m_power(0U),
@@ -191,6 +192,8 @@ bool CConf::read()
 			m_modeHang = (unsigned int)::atoi(value);
 		else if (::strcmp(key, "Display") == 0)
 			m_display = value;
+		else if (::strcmp(key, "Daemon") == 0)
+			m_daemon = ::atoi(value) == 1;
 	} else if (section == SECTION_INFO) {
 		if (::strcmp(key, "TXFrequency") == 0)
 			m_txFrequency = (unsigned int)::atoi(value);
@@ -400,6 +403,11 @@ std::string CConf::getDisplay() const
   return m_display;
 }
 
+bool CConf::getDaemon() const
+{
+	return m_daemon;
+}
+
 unsigned int CConf::getRxFrequency() const
 {
 	return m_rxFrequency;
diff --git a/Conf.h b/Conf.h
index bd1b9ca..2e3e177 100644
--- a/Conf.h
+++ b/Conf.h
@@ -36,6 +36,7 @@ public:
   bool         getDuplex() const;
   unsigned int getModeHang() const;
   std::string  getDisplay() const;
+  bool         getDaemon() const;
 
   // The Info section
   unsigned int getRxFrequency() const;
@@ -134,6 +135,7 @@ private:
   bool         m_duplex;
   unsigned int m_modeHang;
   std::string  m_display;
+  bool         m_daemon;
 
   unsigned int m_rxFrequency;
   unsigned int m_txFrequency;
diff --git a/MMDVM.ini b/MMDVM.ini
index 9de6e3b..5f29c84 100644
--- a/MMDVM.ini
+++ b/MMDVM.ini
@@ -4,6 +4,7 @@ Timeout=180
 Duplex=1
 ModeHang=10
 Display=None
+Daemon=0
 
 [Info]
 RXFrequency=435000000
diff --git a/MMDVMHost.cpp b/MMDVMHost.cpp
index 327d931..d320a42 100644
--- a/MMDVMHost.cpp
+++ b/MMDVMHost.cpp
@@ -38,38 +38,53 @@
 #if !defined(_WIN32) && !defined(_WIN64)
 #include <unistd.h>
 #include <signal.h>
+#include <fcntl.h>
+#endif
+
+#if defined(_WIN32) || defined(_WIN64)
+const char* DEFAULT_INI_FILE = "mmdvm.ini";
+#else
+const char* DEFAULT_INI_FILE = "/etc/mmdvm.ini";
 #endif
 
 static bool m_killed = false;
+static int  m_signal = 0;
 
 #if !defined(_WIN32) && !defined(_WIN64)
-static void sigHandler(int)
+static void sigHandler(int signum)
 {
   m_killed = true;
+  m_signal = signum;
 }
 #endif
 
 const char* HEADER1 = "This software is for use on amateur radio networks only,";
 const char* HEADER2 = "it is to be used for educational purposes only. Its use on";
 const char* HEADER3 = "commercial networks is strictly prohibited.";
-const char* HEADER4 = "Copyright(C) 2015, 2016 by Jonathan Naylor, G4KLX";
+const char* HEADER4 = "Copyright(C) 2015, 2016 by Jonathan Naylor, G4KLX and others";
 
 int main(int argc, char** argv)
 {
-  if (argc == 1) {
-    ::fprintf(stderr, "Usage: MMDVMHost <conf file>\n");
-    return 1;
-  }
+  const char* iniFile = DEFAULT_INI_FILE;
+  if (argc > 1)
+	iniFile = argv[1];
 
 #if !defined(_WIN32) && !defined(_WIN64)
-  ::signal(SIGUSR1, sigHandler);
+  ::signal(SIGTERM, sigHandler);
+  ::signal(SIGHUP,  sigHandler);
 #endif
 
-  CMMDVMHost* host = new CMMDVMHost(std::string(argv[1]));
+  CMMDVMHost* host = new CMMDVMHost(std::string(iniFile));
   int ret2 = host->run();
 
   delete host;
 
+  if (m_signal == 15)
+	  ::LogInfo("Caught SIGTERM. Exiting");
+
+  if (m_signal == 1)
+	  ::LogInfo("Caught SIGHUP. Exiting");
+
   ::LogFinalise();
 
   return ret2;
@@ -108,6 +123,30 @@ int CMMDVMHost::run()
 		return 1;
 	}
 
+#if !defined(_WIN32) && !defined(_WIN64)
+	bool m_daemon = m_conf.getDaemon();
+	if (m_daemon) {
+		// Create new process
+		pid_t pid = ::fork();
+		if (pid == -1)
+			return -1;
+		else if (pid != 0)
+			exit(EXIT_SUCCESS);
+
+		// Create new session and process group
+		if (::setsid() == -1)
+			return -1;
+
+		// Set the working directory to the root directory
+		if (::chdir("/") == -1)
+			return -1;
+
+		::close(STDIN_FILENO);
+		::close(STDOUT_FILENO);
+		::close(STDERR_FILENO);
+	}
+#endif
+
 	LogInfo(HEADER1);
 	LogInfo(HEADER2);
 	LogInfo(HEADER3);