Add signal handlers

Signed-off-by: Mattias Andrée <maandree@kth.se>

1 files changed, 48 insertions, 1 deletions

diff --git a/src/gammad.c b/src/gammad.c
index 92fbf4d..7e981ad 100644
--- a/src/gammad.c
+++ b/src/gammad.c
@@ -56,6 +56,44 @@ size_t outputs_n = 0;
  */
 int socketfd = -1;
 
+/**
+ * Has the process receive a signal
+ * telling it to re-execute?
+ */
+volatile sig_atomic_t reexec = 0;
+
+/**
+ * Has the process receive a signal
+ * telling it to terminate?
+ */
+volatile sig_atomic_t terminate = 0;
+
+
+
+/**
+ * Called when the process receives
+ * a signal telling it to re-execute
+ * 
+ * @param  signo The received signal
+ */
+static void sig_reexec(int signo)
+{
+  reexec = 1;
+  (void) signo;
+}
+
+
+/**
+ * Called when the process receives
+ * a signal telling it to terminate
+ * 
+ * @param  signo The received signal
+ */
+static void sig_terminate(int signo)
+{
+  terminate = 1;
+  (void) signo;
+}
 
 
 /**
@@ -311,6 +349,9 @@ static int is_pidfile_reusable(const char* pidfile, const char* token)
 /**
  * Create PID file
  * 
+ * @signal  SIGUSR1  Re-execute to updated process image
+ * @signal  SIGTERM  Terminate the process gracefully
+ * 
  * @param   pidfile  The pathname of the PID file
  * @return           Zero on success, -1 on error,
  *                   -2 if the service is already running
@@ -635,10 +676,16 @@ int main(int argc, char** argv)
       goto fail;
   }
   
-  /* Change directory to / to avoid blocking umounting. */
+  /* Change directory to / to avoid blocking umounting */
   if (chdir("/") < 0)
     perror(argv0);
   
+  /* Set up signal handlers */
+  if (signal(SIGUSR1, sig_reexec) == SIG_ERR)
+    goto fail;
+  if (signal(SIGTERM, sig_terminate) == SIG_ERR)
+    goto fail;
+  
   /* Place in the background unless -f */
   if (foreground == 0)
     {