(main): Rewrite signal-catching code to make it

similar to other coreutils programs.  When processing signals,
block all signals that we catch, but do not block signals that we
don't catch.  Avoid problems with unsigned int warnings.

(sighandler) [defined SA_NOCLDSTOP]:
Use simpler "signal (sig, SIG_DFL)" rather than sigaction equivalent.

1 files changed, 21 insertions, 36 deletions

diff --git a/src/sort.c b/src/sort.c
index b67582a03..942de4fff 100644
--- a/src/sort.c
+++ b/src/sort.c
@@ -2133,19 +2133,7 @@ sighandler (int sig)
 
   cleanup ();
 
-#ifdef SA_NOCLDSTOP
-  {
-    struct sigaction sigact;
-
-    sigact.sa_handler = SIG_DFL;
-    sigemptyset (&sigact.sa_mask);
-    sigact.sa_flags = 0;
-    sigaction (sig, &sigact, NULL);
-  }
-#else
   signal (sig, SIG_DFL);
-#endif
-
   raise (sig);
 }
 
@@ -2225,11 +2213,6 @@ main (int argc, char **argv)
 			       : COMMON_SHORT_OPTIONS "y:");
   char *minus = "-", **files;
   char const *outfile = minus;
-  static int const sigs[] = { SIGHUP, SIGINT, SIGPIPE, SIGTERM };
-  unsigned int nsigs = sizeof sigs / sizeof *sigs;
-#ifdef SA_NOCLDSTOP
-  struct sigaction oldact, newact;
-#endif
 
   initialize_main (&argc, &argv);
   program_name = argv[0];
@@ -2269,32 +2252,34 @@ main (int argc, char **argv)
   have_read_stdin = false;
   inittables ();
 
-#ifdef SA_NOCLDSTOP
   {
-    unsigned int i;
+    int i;
+    static int const sig[] = { SIGHUP, SIGINT, SIGPIPE, SIGTERM };
+    enum { nsigs = sizeof sig / sizeof sig[0] };
+
+#ifdef SA_NOCLDSTOP
+    struct sigaction act;
+
     sigemptyset (&caught_signals);
     for (i = 0; i < nsigs; i++)
-      sigaddset (&caught_signals, sigs[i]);
-    newact.sa_handler = sighandler;
-    newact.sa_mask = caught_signals;
-    newact.sa_flags = 0;
-  }
-#endif
+      {
+	sigaction (sig[i], NULL, &act);
+	if (act.sa_handler != SIG_IGN)
+	  sigaddset (&caught_signals, sig[i]);
+      }
+
+    act.sa_handler = sighandler;
+    act.sa_mask = caught_signals;
+    act.sa_flags = 0;
 
-  {
-    unsigned int i;
     for (i = 0; i < nsigs; i++)
-      {
-	int sig = sigs[i];
-#ifdef SA_NOCLDSTOP
-	sigaction (sig, NULL, &oldact);
-	if (oldact.sa_handler != SIG_IGN)
-	  sigaction (sig, &newact, NULL);
+      if (sigismember (&caught_signals, sig[i]))
+	sigaction (sig[i], &act, NULL);
 #else
-	if (signal (sig, SIG_IGN) != SIG_IGN)
-	  signal (sig, sighandler);
+    for (i = 0; i < nsigs; i++)
+      if (signal (sig[i], SIG_IGN) != SIG_IGN)
+	signal (sig[i], sighandler);
 #endif
-      }
   }
 
   gkey.sword = gkey.eword = SIZE_MAX;