X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=lib%2Ffatal-signal.c;h=aca9027e9a891883f74ea35a89ba7a9f51b0fc6a;hb=2aa729ac6af316bc30111144684a51c4650d5c44;hp=64b346d8747b4637bcc684bc74a706ad8445e2e6;hpb=1a894ea4dbb6c042c5eb447839549c5f2d4f4e17;p=gnulib.git

diff --git a/lib/fatal-signal.c b/lib/fatal-signal.c
index 64b346d87..aca9027e9 100644
--- a/lib/fatal-signal.c
+++ b/lib/fatal-signal.c
@@ -1,5 +1,5 @@
 /* Emergency actions in case of a fatal signal.
-   Copyright (C) 2003-2004, 2006-2008 Free Software Foundation, Inc.
+   Copyright (C) 2003-2004, 2006-2011 Free Software Foundation, Inc.
    Written by Bruno Haible <bruno@clisp.org>, 2003.
 
    This program is free software: you can redistribute it and/or modify
@@ -91,13 +91,13 @@ init_fatal_signals (void)
       size_t i;
 
       for (i = 0; i < num_fatal_signals; i++)
-	{
-	  struct sigaction action;
+        {
+          struct sigaction action;
 
-	  if (sigaction (fatal_signals[i], NULL, &action) >= 0
-	      && get_handler (&action) == SIG_IGN)
-	    fatal_signals[i] = -1;
-	}
+          if (sigaction (fatal_signals[i], NULL, &action) >= 0
+              && get_handler (&action) == SIG_IGN)
+            fatal_signals[i] = -1;
+        }
 
       fatal_signals_initialized = true;
     }
@@ -125,19 +125,25 @@ static sig_atomic_t volatile actions_count = 0;
 static size_t actions_allocated = SIZEOF (static_actions);
 
 
+/* The saved signal handlers.
+   Size 32 would not be sufficient: On HP-UX, SIGXCPU = 33, SIGXFSZ = 34.  */
+static struct sigaction saved_sigactions[64];
+
+
 /* Uninstall the handlers.  */
 static inline void
 uninstall_handlers ()
 {
   size_t i;
-  struct sigaction action;
 
-  action.sa_handler = SIG_DFL;
-  action.sa_flags = 0;
-  sigemptyset (&action.sa_mask);
   for (i = 0; i < num_fatal_signals; i++)
     if (fatal_signals[i] >= 0)
-      sigaction (fatal_signals[i], &action, NULL);
+      {
+        int sig = fatal_signals[i];
+        if (saved_sigactions[sig].sa_handler == SIG_IGN)
+          saved_sigactions[sig].sa_handler = SIG_DFL;
+        sigaction (sig, &saved_sigactions[sig], NULL);
+      }
 }
 
 
@@ -151,7 +157,7 @@ fatal_signal_handler (int sig)
       action_t action;
       size_t n = actions_count;
       if (n == 0)
-	break;
+        break;
       n--;
       actions_count = n;
       action = actions[n].action;
@@ -184,7 +190,13 @@ install_handlers ()
   sigemptyset (&action.sa_mask);
   for (i = 0; i < num_fatal_signals; i++)
     if (fatal_signals[i] >= 0)
-      sigaction (fatal_signals[i], &action, NULL);
+      {
+        int sig = fatal_signals[i];
+
+        if (!(sig < sizeof (saved_sigactions) / sizeof (saved_sigactions[0])))
+          abort ();
+        sigaction (sig, &action, &saved_sigactions[sig]);
+      }
 }
 
 
@@ -204,25 +216,25 @@ at_fatal_signal (action_t action)
   if (actions_count == actions_allocated)
     {
       /* Extend the actions array.  Note that we cannot use xrealloc(),
-	 because then the cleanup() function could access an already
-	 deallocated array.  */
+         because then the cleanup() function could access an already
+         deallocated array.  */
       actions_entry_t *old_actions = actions;
       size_t old_actions_allocated = actions_allocated;
       size_t new_actions_allocated = 2 * actions_allocated;
       actions_entry_t *new_actions =
-	XNMALLOC (new_actions_allocated, actions_entry_t);
+        XNMALLOC (new_actions_allocated, actions_entry_t);
       size_t k;
 
       /* Don't use memcpy() here, because memcpy takes non-volatile arguments
-	 and is therefore not guaranteed to complete all memory stores before
-	 the next statement.  */
+         and is therefore not guaranteed to complete all memory stores before
+         the next statement.  */
       for (k = 0; k < old_actions_allocated; k++)
-	new_actions[k] = old_actions[k];
+        new_actions[k] = old_actions[k];
       actions = new_actions;
       actions_allocated = new_actions_allocated;
       /* Now we can free the old actions array.  */
       if (old_actions != static_actions)
-	free (old_actions);
+        free (old_actions);
     }
   /* The two uses of 'volatile' in the types above (and ISO C 99 section
      5.1.2.3.(5)) ensure that we increment the actions_count only after
@@ -250,8 +262,8 @@ init_fatal_signal_set ()
 
       sigemptyset (&fatal_signal_set);
       for (i = 0; i < num_fatal_signals; i++)
-	if (fatal_signals[i] >= 0)
-	  sigaddset (&fatal_signal_set, fatal_signals[i]);
+        if (fatal_signals[i] >= 0)
+          sigaddset (&fatal_signal_set, fatal_signals[i]);
 
       fatal_signal_set_initialized = true;
     }