(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.

diff --git a/src/sort.c b/src/sort.c
index b67582a038170c2e4d3060dfec818607343a87dd..942de4fff9fbbabcd52948f431a9fdade267494d 100644 (file)
--- 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;