2008-07-12 Pedro Alves <pedro@codesourcery.com>

Rewrite continuations internals on top of cleanups and plug
	continuation arguments leaks.

	* defs.h (struct continuation): Make it opaque.
	(add_continuation, add_intermediate_continuation): Drop the int
	argument of the continuation hook argument.  Add
	continuation_free_args argument.
	(do_all_continuations, do_all_intermediate_continuations): Drop
	the error_p argument.

	* utils.c (add_continuation): Drop the int argument of the
	continuation hook argument.  Add continuation_free_args argument.
	Reimplement on top of cleanups.
	(do_all_continuations): Drop error argument.  Reimplement on top
	of cleanups.
	(discard_all_continuations): Reimplement on top of cleanups.
	(add_intermediate_continuation): Drop the int argument of the
	continuation hook argument.  Add continuation_free_args argument.
	Reimplement on top of cleanups.
	(do_all_intermediate_continuations): Drop error argument.
	Reimplement on top of cleanups.
	(discard_all_intermediate_continuations): Reimplement on top of
	cleanups.

	* breakpoint.c (until_break_command_continuation): Drop error
	argument.  Add xfree as continuation argument deleter.

	* inf-loop.c (inferior_event_handler): On error, discard all
	continuations.  Adjust to new do_all_intermediate_continuations
	and do_all_continuations interfaces.

	* infcmd.c (step_1_continuation): Drop error_p argument.  Adjust.
	Pass xfree as continuation argument deleter.
	(finish_command_continuation): Drop error_p argument.  Adjust.
	(finish_command_continuation_free_arg): New.
	(finish_command): Pass finish_command_continuation_free_arg as
	continuation argument deleter.  Adjust to new do_all_continuations
	interfaces.
	(attach_command_continuation): Drop error_p argument.
	(attach_command_continuation_free_args): New.
	(attach_command): Pass attach_command_continuation_free_args as
	continuation argument deleter.

	* interps.c (interp_set): Adjust to new do_all_continuations
	interfaces.

	* event-top.c (stdin_event_handler): In error, also discard the
	intermediate continuations.

gdb/infcmd.c

@@ -73,8 +73,6 @@ static void nofp_registers_info (char *, int);
 static void print_return_value (struct type *func_type,
 				struct type *value_type);
 
-static void finish_command_continuation (void *args, int error_p);
-
 static void until_next_command (int);
 
 static void until_command (char *, int);
@@ -107,7 +105,6 @@ static void jump_command (char *, int);
 
 static void step_1 (int, int, char *);
 static void step_once (int skip_subroutines, int single_inst, int count, int thread);
-static void step_1_continuation (void *args, int error_p);
 
 static void next_command (char *, int);
 
@@ -877,15 +874,14 @@ struct step_1_continuation_args
    proceed(), via step_once(). Basically it is like step_once and
    step_1_continuation are co-recursive. */
 static void
-step_1_continuation (void *args, int error_p)
+step_1_continuation (void *args)
 {
   struct step_1_continuation_args *a = args;
 
-  if (error_p || !step_multi || !stop_step)
+  if (!step_multi || !stop_step)
     {
-      /* We either hit an error, or stopped for some reason
-	 that is not stepping, or there are no further steps
-	 to make.  Cleanup.  */
+      /* If we stopped for some reason that is not stepping there are
+	 no further steps to make.  Cleanup.  */
       if (!a->single_inst || a->skip_subroutines)
 	delete_longjmp_breakpoint (a->thread);
       step_multi = 0;
@@ -960,7 +956,7 @@ which has no line number information.\n"), name);
       args->single_inst = single_inst;
       args->count = count;
       args->thread = thread;
-      add_intermediate_continuation (step_1_continuation, args);
+      add_intermediate_continuation (step_1_continuation, args, xfree);
     }
 }
 
@@ -1325,35 +1321,44 @@ struct finish_command_continuation_args
 };
 
 static void
-finish_command_continuation (void *arg, int error_p)
+finish_command_continuation (void *arg)
 {
   struct finish_command_continuation_args *a = arg;
 
-  if (!error_p)
+  if (bpstat_find_breakpoint (stop_bpstat, a->breakpoint) != NULL
+      && a->function != NULL)
     {
-      if (bpstat_find_breakpoint (stop_bpstat, a->breakpoint) != NULL
-	  && a->function != NULL)
-	{
-	  struct type *value_type;
+      struct type *value_type;
 
-	  value_type = TYPE_TARGET_TYPE (SYMBOL_TYPE (a->function));
-	  if (!value_type)
-	    internal_error (__FILE__, __LINE__,
-			    _("finish_command: function has no target type"));
+      value_type = TYPE_TARGET_TYPE (SYMBOL_TYPE (a->function));
+      if (!value_type)
+	internal_error (__FILE__, __LINE__,
+			_("finish_command: function has no target type"));
 
-	  if (TYPE_CODE (value_type) != TYPE_CODE_VOID)
-	    print_return_value (SYMBOL_TYPE (a->function), value_type);
-	}
-
-      /* We suppress normal call of normal_stop observer and do it here so that
-	 that *stopped notification includes the return value.  */
-      observer_notify_normal_stop (stop_bpstat);
+      if (TYPE_CODE (value_type) != TYPE_CODE_VOID)
+	print_return_value (SYMBOL_TYPE (a->function), value_type);
     }
 
+  /* We suppress normal call of normal_stop observer and do it here so
+     that that *stopped notification includes the return value.  */
+  /* NOTE: This is broken in non-stop mode.  There is no guarantee the
+     next stop will be in the same thread that we started doing a
+     finish on.  This suppressing (or some other replacement means)
+     should be a thread property.  */
+  observer_notify_normal_stop (stop_bpstat);
   suppress_stop_observer = 0;
   delete_breakpoint (a->breakpoint);
 }
 
+static void
+finish_command_continuation_free_arg (void *arg)
+{
+  /* NOTE: See finish_command_continuation.  This would go away, if
+     this suppressing is made a thread property.  */
+  suppress_stop_observer = 0;
+  xfree (arg);
+}
+
 /* "finish": Set a temporary breakpoint at the place the selected
    frame will return to, then continue.  */
 
@@ -1425,11 +1430,12 @@ finish_command (char *arg, int from_tty)
 
   cargs->breakpoint = breakpoint;
   cargs->function = function;
-  add_continuation (finish_command_continuation, cargs);
+  add_continuation (finish_command_continuation, cargs,
+		    finish_command_continuation_free_arg);
 
   discard_cleanups (old_chain);
   if (!target_can_async_p ())
-    do_all_continuations (0);
+    do_all_continuations ();
 }
 
 
@@ -1982,12 +1988,20 @@ struct attach_command_continuation_args
 };
 
 static void
-attach_command_continuation (void *args, int error_p)
+attach_command_continuation (void *args)
 {
   struct attach_command_continuation_args *a = args;
   attach_command_post_wait (a->args, a->from_tty, a->async_exec);
 }
 
+static void
+attach_command_continuation_free_args (void *args)
+{
+  struct attach_command_continuation_args *a = args;
+  xfree (a->args);
+  xfree (a);
+}
+
 void
 attach_command (char *args, int from_tty)
 {
@@ -2076,7 +2090,8 @@ attach_command (char *args, int from_tty)
 	  a->args = xstrdup (args);
 	  a->from_tty = from_tty;
 	  a->async_exec = async_exec;
-	  add_continuation (attach_command_continuation, a);
+	  add_continuation (attach_command_continuation, a,
+			    attach_command_continuation_free_args);
 	  return;
 	}