rewrite signal handler

diff --git a/scrotwm.c b/scrotwm.c
index 67ad17a..49dec92 100644 (file)
--- a/scrotwm.c
+++ b/scrotwm.c
@@ -599,16 +599,36 @@ void                      (*handler[LASTEvent])(XEvent *) = {
 void
 sighdlr(int sig)
 {
+       int                     saved_errno, status;
        pid_t                   pid;
 
+       saved_errno = errno;
+
        switch (sig) {
        case SIGCHLD:
-               while ((pid = waitpid(WAIT_ANY, NULL, WNOHANG)) != -1) {
-                       DNPRINTF(SWM_D_MISC, "reaping: %d\n", pid);
-                       if (pid <= 0)
+               while ((pid = waitpid(WAIT_ANY, &status, WNOHANG)) != 0) {
+                       if (pid == -1) {
+                               if (errno == EINTR)
+                                       continue;
+#ifdef SWM_DEBUG
+                               if (errno != ECHILD)
+                                       warn("sighdlr: waitpid");
+#endif /* SWM_DEBUG */
                                break;
+                       }
+
+#ifdef SWM_DEBUG
+                       if (WIFEXITED(status)) {
+                               if (WEXITSTATUS(status) != 0)
+                                       warnx("sighdlr: child exit status: %d",
+                                           WEXITSTATUS(status));
+                       } else
+                               warnx("sighdlr: child is terminated "
+                                   "abnormally");
+#endif /* SWM_DEBUG */
                }
                break;
+
        case SIGHUP:
                restart_wm = 1;
                break;
@@ -618,18 +638,8 @@ sighdlr(int sig)
                running = 0;
                break;
        }
-}
-
-void
-installsignal(int sig, char *name)
-{
-       struct sigaction        sa;
 
-       sa.sa_handler = sighdlr;
-       sigemptyset(&sa.sa_mask);
-       sa.sa_flags = 0;
-       if (sigaction(sig, &sa, NULL) == -1)
-               err(1, "could not install %s handler", name);
+       errno = saved_errno;
 }
 
 unsigned long
@@ -4806,6 +4816,7 @@ main(int argc, char *argv[])
        XEvent                  e;
        int                     xfd, i;
        fd_set                  rd;
+       struct sigaction        sact;
 
        start_argv = argv;
        fprintf(stderr, "Welcome to scrotwm V%s cvs tag: %s\n",
@@ -4819,12 +4830,19 @@ main(int argc, char *argv[])
        if (active_wm())
                errx(1, "other wm running");
 
-       /* handle some signale */
-       installsignal(SIGINT, "INT");
-       installsignal(SIGHUP, "HUP");
-       installsignal(SIGQUIT, "QUIT");
-       installsignal(SIGTERM, "TERM");
-       installsignal(SIGCHLD, "CHLD");
+       /* handle some signals */
+       bzero(&sact, sizeof(sact));
+       sigemptyset(&sact.sa_mask);
+       sact.sa_flags = 0;
+       sact.sa_handler = sighdlr;
+       sigaction(SIGINT, &sact, NULL);
+       sigaction(SIGQUIT, &sact, NULL);
+       sigaction(SIGTERM, &sact, NULL);
+       sigaction(SIGHUP, &sact, NULL);
+
+       sact.sa_handler = sighdlr;
+       sact.sa_flags = SA_NOCLDSTOP;
+       sigaction(SIGCHLD, &sact, NULL);
 
        astate = XInternAtom(display, "WM_STATE", False);
        aprot = XInternAtom(display, "WM_PROTOCOLS", False);