src: call unmask after install signal handler

PR-URL: nodejs#59059
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Benjamin Gruenbaum <benjamingr@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>

Author: theanarkh

src/inspector_agent.cc

@@ -123,12 +123,11 @@ static int StartDebugSignalHandler() {
   CHECK_EQ(0, pthread_sigmask(SIG_SETMASK, &sigmask, &savemask));
   sigmask = savemask;
   pthread_t thread;
-  const int err = pthread_create(&thread, &attr,
-                                 StartIoThreadMain, nullptr);
-  // Restore original mask
-  CHECK_EQ(0, pthread_sigmask(SIG_SETMASK, &sigmask, nullptr));
+  const int err = pthread_create(&thread, &attr, StartIoThreadMain, nullptr);
   CHECK_EQ(0, pthread_attr_destroy(&attr));
   if (err != 0) {
+    // Restore original mask
+    CHECK_EQ(0, pthread_sigmask(SIG_SETMASK, &sigmask, nullptr));
     fprintf(stderr, "node[%u]: pthread_create: %s\n",
             uv_os_getpid(), strerror(err));
     fflush(stderr);
@@ -137,6 +136,8 @@ static int StartDebugSignalHandler() {
     return -err;
   }
   RegisterSignalHandler(SIGUSR1, StartIoThreadWakeup);
+  // Restore original mask
+  CHECK_EQ(0, pthread_sigmask(SIG_SETMASK, &sigmask, nullptr));
   // Unblock SIGUSR1.  A pending SIGUSR1 signal will now be delivered.
   sigemptyset(&sigmask);
   sigaddset(&sigmask, SIGUSR1);

src/node_watchdog.cc

@@ -308,7 +308,10 @@ int SigintWatchdogHelper::Start() {
   CHECK_EQ(0, pthread_sigmask(SIG_SETMASK, &sigmask, &savemask));
   sigmask = savemask;
   int ret = pthread_create(&thread_, nullptr, RunSigintWatchdog, nullptr);
-  CHECK_EQ(0, pthread_sigmask(SIG_SETMASK, &sigmask, nullptr));
+
+  auto cleanup = OnScopeLeave(
+      [&]() { CHECK_EQ(0, pthread_sigmask(SIG_SETMASK, &sigmask, nullptr)); });
+
   if (ret != 0) {
     return ret;
   }