RFA: fix handling of catch signal SIGTRAP/SIGINT

[Philippe Waroquiers <philippe.waroquiers@skynet.be>]

catch signal SIGTRAP/SIGINT is not working when the signal
is catched specifically with 'catch signal SIGTRAP'.

This is because the function signal_catchpoint_breakpoint_hit
still checks !INTERNAL_SIGNAL (signal_number) even
when the signal_number is member of c->signals_to_be_caught

The attached patch fixes this, and modifies gdb.base/catch-signal.exp
to test that SIGINT (one of the two internal signals) is properly
catched.

Ok to apply ?

Index: gdb/ChangeLog
===================================================================
RCS file: /cvs/src/src/gdb/ChangeLog,v
retrieving revision 1.15494
diff -u -p -r1.15494 ChangeLog
--- gdb/ChangeLog	30 Apr 2013 23:19:41 -0000	1.15494
+++ gdb/ChangeLog	1 May 2013 13:50:36 -0000
@@ -1,3 +1,9 @@
+2013-05-01  Philippe Waroquiers  <philippe.waroquiers@skynet.be>
+
+	* break-catch-sig.c (signal_catchpoint_breakpoint_hit): do not
+	ignore SIGINT and SIGTRAP in case these internals signals are
+	catched explicitely.
+
 2013-04-30  Doug Evans  <dje@google.com>
 
 	* dwarf2read.c (lookup_dwo_unit): Return NULL if DWO not found.
Index: gdb/break-catch-sig.c
===================================================================
RCS file: /cvs/src/src/gdb/break-catch-sig.c,v
retrieving revision 1.3
diff -u -p -r1.3 break-catch-sig.c
--- gdb/break-catch-sig.c	12 Feb 2013 18:27:27 -0000	1.3
+++ gdb/break-catch-sig.c	1 May 2013 13:50:36 -0000
@@ -199,13 +199,13 @@ signal_catchpoint_breakpoint_hit (const 
            VEC_iterate (gdb_signal_type, c->signals_to_be_caught, i, iter);
            i++)
 	if (signal_number == iter)
-	  break;
+	  return 1;
       /* Not the same.  */
-      if (!iter)
-	return 0;
+      gdb_assert (!iter);
+      return 0;
     }
-
-  return c->catch_all || !INTERNAL_SIGNAL (signal_number);
+  else
+    return c->catch_all || !INTERNAL_SIGNAL (signal_number);
 }
 
 /* Implement the "print_it" breakpoint_ops method for signal
Index: gdb/testsuite/ChangeLog
===================================================================
RCS file: /cvs/src/src/gdb/testsuite/ChangeLog,v
retrieving revision 1.3640
diff -u -p -r1.3640 ChangeLog
--- gdb/testsuite/ChangeLog	30 Apr 2013 12:33:51 -0000	1.3640
+++ gdb/testsuite/ChangeLog	1 May 2013 13:50:39 -0000
@@ -1,3 +1,8 @@
+2013-05-01  Philippe Waroquiers  <philippe.waroquiers@skynet.be>
+
+	* gdb.base/catch-sig.c (main): add raise SIGINT.
+	* gdb.base/catch-sig.exp: test catch signal SIGINT.
+
 2013-03-27  Walfred Tedeschi  <walfred.tedeschi@intel.com>
 
 	* gdb.xml/maint_print_struct.exp: New file.
Index: gdb/testsuite/gdb.base/catch-signal.c
===================================================================
RCS file: /cvs/src/src/gdb/testsuite/gdb.base/catch-signal.c,v
retrieving revision 1.2
diff -u -p -r1.2 catch-signal.c
--- gdb/testsuite/gdb.base/catch-signal.c	12 Feb 2013 18:27:28 -0000	1.2
+++ gdb/testsuite/gdb.base/catch-signal.c	1 May 2013 13:50:39 -0000
@@ -42,5 +42,7 @@ main ()
   raise (SIGHUP);		/* third HUP */
 
   raise (SIGHUP);		/* fourth HUP */
+
+  raise (SIGINT);               /* first INT */
 }
 
Index: gdb/testsuite/gdb.base/catch-signal.exp
===================================================================
RCS file: /cvs/src/src/gdb/testsuite/gdb.base/catch-signal.exp,v
retrieving revision 1.3
diff -u -p -r1.3 catch-signal.exp
--- gdb/testsuite/gdb.base/catch-signal.exp	12 Feb 2013 18:27:28 -0000	1.3
+++ gdb/testsuite/gdb.base/catch-signal.exp	1 May 2013 13:50:39 -0000
@@ -71,6 +71,23 @@ proc test_catch_signal {signame} {
 	gdb_breakpoint ${srcfile}:[gdb_get_line_number "fourth HUP"]
 	gdb_continue_to_breakpoint "fourth HUP"
 	delete_breakpoints
+
+	# Verify an signal used by gdb is properly catched
+	gdb_breakpoint ${srcfile}:[gdb_get_line_number "first INT"]
+	gdb_continue_to_breakpoint "first INT"
+	set test "override SIGINT to catch"
+	gdb_test_multiple "handle SIGINT nostop print nopass" "$test" {
+	    -re "SIGINT is used by the debugger.*Are you sure you want to change it.*y or n.*" {
+		gdb_test_multiple "y" "$test" {
+		    -re 	    "SIGINT.*No.*Yes.*No.*" {
+			pass "$test"
+		    }
+		}
+	    }
+	}
+	gdb_test "catch signal SIGINT" "Catchpoint .*"
+	gdb_test "continue" "Catchpoint .*"
+        
     }
 }