Merge #10057: [init] Deduplicated sigaction() boilerplate

81a3857 Deduplicated sigaction() boilerplate (Thomas Snider)

Tree-SHA512: 705b73f285a3d76504ba01476e072fdce67731b65f309bb04e4bbd765556c37e127cb769b475de2d68b33f50d7737fb136aefa0fa7c725a11ad16a47b9d0365f

src/init.cpp

@@ -265,18 +265,31 @@ void Shutdown()
 }
 
 /**
- * Signal handlers are very limited in what they are allowed to do, so:
+ * Signal handlers are very limited in what they are allowed to do.
+ * The execution context the handler is invoked in is not guaranteed,
+ * so we restrict handler operations to just touching variables:
  */
-void HandleSIGTERM(int)
+static void HandleSIGTERM(int)
 {
     fRequestShutdown = true;
 }
 
-void HandleSIGHUP(int)
+static void HandleSIGHUP(int)
 {
     fReopenDebugLog = true;
 }
 
+#ifndef WIN32
+static void registerSignalHandler(int signal, void(*handler)(int))
+{
+    struct sigaction sa;
+    sa.sa_handler = handler;
+    sigemptyset(&sa.sa_mask);
+    sa.sa_flags = 0;
+    sigaction(signal, &sa, NULL);
+}
+#endif
+
 bool static Bind(CConnman& connman, const CService &addr, unsigned int flags) {
     if (!(flags & BF_EXPLICIT) && IsLimited(addr))
         return false;
@@ -848,19 +861,11 @@ bool AppInitBasicSetup()
     }
 
     // Clean shutdown on SIGTERM
-    struct sigaction sa;
+    registerSignalHandler(SIGTERM, HandleSIGTERM);
-    sa.sa_handler = HandleSIGTERM;
+    registerSignalHandler(SIGINT, HandleSIGTERM);
-    sigemptyset(&sa.sa_mask);
-    sa.sa_flags = 0;
-    sigaction(SIGTERM, &sa, NULL);
-    sigaction(SIGINT, &sa, NULL);
 
     // Reopen debug.log on SIGHUP
-    struct sigaction sa_hup;
+    registerSignalHandler(SIGHUP, HandleSIGHUP);
-    sa_hup.sa_handler = HandleSIGHUP;
-    sigemptyset(&sa_hup.sa_mask);
-    sa_hup.sa_flags = 0;
-    sigaction(SIGHUP, &sa_hup, NULL);
 
     // Ignore SIGPIPE, otherwise it will bring the daemon down if the client closes unexpectedly
     signal(SIGPIPE, SIG_IGN);