Return bool from breakpoint_ops::print_one

This changes breakpoint_ops::print_one to return bool, and updates all
the implementations and the caller.  The caller is changed so that a
NULL check is no longer needed -- something that will be impossible
with a real method.

gdb/ada-lang.c

@@ -12380,7 +12380,7 @@ print_it_exception (bpstat *bs)
 /* Implement the PRINT_ONE method in the breakpoint_ops structure
    for all exception catchpoint kinds.  */
 
-static void
+static bool
 print_one_exception (struct breakpoint *b, struct bp_location **last_loc)
 { 
   struct ui_out *uiout = current_uiout;
@@ -12431,6 +12431,8 @@ print_one_exception (struct breakpoint *b, struct bp_location **last_loc)
 	internal_error (__FILE__, __LINE__, _("unexpected catchpoint type"));
 	break;
     }
+
+  return true;
 }
 
 /* Implement the PRINT_MENTION method in the breakpoint_ops structure

gdb/break-catch-exec.c

@@ -94,7 +94,7 @@ print_it_catch_exec (bpstat *bs)
   return PRINT_SRC_AND_LOC;
 }
 
-static void
+static bool
 print_one_catch_exec (struct breakpoint *b, struct bp_location **last_loc)
 {
   struct exec_catchpoint *c = (struct exec_catchpoint *) b;
@@ -119,6 +119,8 @@ print_one_catch_exec (struct breakpoint *b, struct bp_location **last_loc)
 
   if (uiout->is_mi_like_p ())
     uiout->field_string ("catch-type", "exec");
+
+  return true;
 }
 
 static void

gdb/break-catch-fork.c

@@ -127,7 +127,7 @@ print_it_catch_fork (bpstat *bs)
 /* Implement the "print_one" breakpoint_ops method for fork
    catchpoints.  */
 
-static void
+static bool
 print_one_catch_fork (struct breakpoint *b, struct bp_location **last_loc)
 {
   struct fork_catchpoint *c = (struct fork_catchpoint *) b;
@@ -153,6 +153,8 @@ print_one_catch_fork (struct breakpoint *b, struct bp_location **last_loc)
 
   if (uiout->is_mi_like_p ())
     uiout->field_string ("catch-type", name);
+
+  return true;
 }
 
 /* Implement the "print_mention" breakpoint_ops method for fork

gdb/break-catch-load.c

@@ -137,7 +137,7 @@ print_it_catch_solib (bpstat *bs)
   return PRINT_SRC_AND_LOC;
 }
 
-static void
+static bool
 print_one_catch_solib (struct breakpoint *b, struct bp_location **locs)
 {
   struct solib_catchpoint *self = (struct solib_catchpoint *) b;
@@ -176,6 +176,8 @@ print_one_catch_solib (struct breakpoint *b, struct bp_location **locs)
 
   if (uiout->is_mi_like_p ())
     uiout->field_string ("catch-type", self->is_load ? "load" : "unload");
+
+  return true;
 }
 
 static void

gdb/break-catch-sig.c

@@ -201,7 +201,7 @@ signal_catchpoint_print_it (bpstat *bs)
 /* Implement the "print_one" breakpoint_ops method for signal
    catchpoints.  */
 
-static void
+static bool
 signal_catchpoint_print_one (struct breakpoint *b,
 			     struct bp_location **last_loc)
 {
@@ -248,6 +248,8 @@ signal_catchpoint_print_one (struct breakpoint *b,
 
   if (uiout->is_mi_like_p ())
     uiout->field_string ("catch-type", "signal");
+
+  return true;
 }
 
 /* Implement the "print_mention" breakpoint_ops method for signal

gdb/break-catch-syscall.c

@@ -226,7 +226,7 @@ print_it_catch_syscall (bpstat *bs)
 /* Implement the "print_one" breakpoint_ops method for syscall
    catchpoints.  */
 
-static void
+static bool
 print_one_catch_syscall (struct breakpoint *b,
 			 struct bp_location **last_loc)
 {
@@ -275,6 +275,8 @@ print_one_catch_syscall (struct breakpoint *b,
 
   if (uiout->is_mi_like_p ())
     uiout->field_string ("catch-type", "syscall");
+
+  return true;
 }
 
 /* Implement the "print_mention" breakpoint_ops method for syscall

gdb/break-catch-throw.c

@@ -253,7 +253,7 @@ print_it_exception_catchpoint (bpstat *bs)
   return PRINT_SRC_AND_LOC;
 }
 
-static void
+static bool
 print_one_exception_catchpoint (struct breakpoint *b, 
 				struct bp_location **last_loc)
 {
@@ -287,6 +287,8 @@ print_one_exception_catchpoint (struct breakpoint *b,
 	uiout->field_string ("catch-type", "catch");
       break;
     }
+
+  return true;
 }
 
 /* Implement the 'print_one_detail' method.  */

gdb/breakpoint.c

@@ -6058,9 +6058,10 @@ output_thread_groups (struct ui_out *uiout,
    instead of going via breakpoint_ops::print_one.  This makes "maint
    info breakpoints" show the software breakpoint locations of
    catchpoints, which are considered internal implementation
-   detail.  */
+   detail.  Returns true if RAW_LOC is false and if the breakpoint's
+   print_one method did something; false otherwise.  */
 
-static void
+static bool
 print_one_breakpoint_location (struct breakpoint *b,
 			       struct bp_location *loc,
 			       int loc_number,
@@ -6124,8 +6125,9 @@ print_one_breakpoint_location (struct breakpoint *b,
     uiout->field_fmt ("enabled", "%c", bpenables[(int) b->enable_state]);
 
   /* 5 and 6 */
-  if (!raw_loc && b->ops != NULL && b->ops->print_one != NULL)
-    b->ops->print_one (b, last_loc);
+  bool result = false;
+  if (!raw_loc && b->ops != NULL && b->ops->print_one (b, last_loc))
+    result = true;
   else
     {
       if (is_watchpoint (b))
@@ -6372,6 +6374,8 @@ print_one_breakpoint_location (struct breakpoint *b,
 	uiout->field_string ("original-location",
 			     event_location_to_string (b->location.get ()));
     }
+
+  return result;
 }
 
 /* See breakpoint.h. */
@@ -6389,7 +6393,8 @@ print_one_breakpoint (struct breakpoint *b,
        || fix_multi_location_breakpoint_output_globally);
 
   gdb::optional<ui_out_emit_tuple> bkpt_tuple_emitter (gdb::in_place, uiout, "bkpt");
-  print_one_breakpoint_location (b, NULL, 0, last_loc, allflag, false);
+  bool printed = print_one_breakpoint_location (b, NULL, 0, last_loc,
+						allflag, false);
 
   /* The mi2 broken format: the main breakpoint tuple ends here, the locations
      are outside.  */
@@ -6399,9 +6404,7 @@ print_one_breakpoint (struct breakpoint *b,
   /* If this breakpoint has custom print function,
      it's already printed.  Otherwise, print individual
      locations, if any.  */
-  if (b->ops == NULL
-      || b->ops->print_one == NULL
-      || allflag)
+  if (!printed || allflag)
     {
       /* If breakpoint has a single location that is disabled, we
 	 print it as if it had several locations, since otherwise it's
@@ -9174,7 +9177,7 @@ print_it_ranged_breakpoint (bpstat *bs)
 /* Implement the "print_one" breakpoint_ops method for
    ranged breakpoints.  */
 
-static void
+static bool
 print_one_ranged_breakpoint (struct breakpoint *b,
 			     struct bp_location **last_loc)
 {
@@ -9194,6 +9197,8 @@ print_one_ranged_breakpoint (struct breakpoint *b,
   annotate_field (5);
   print_breakpoint_location (b, bl);
   *last_loc = bl;
+
+  return true;
 }
 
 /* Implement the "print_one_detail" breakpoint_ops method for
@@ -11549,6 +11554,12 @@ base_breakpoint_print_it (bpstat *bs)
   internal_error_pure_virtual_called ();
 }
 
+static bool
+base_breakpoint_print_one (struct breakpoint *, struct bp_location **)
+{
+  return false;
+}
+
 static void
 base_breakpoint_print_one_detail (const struct breakpoint *self,
 				  struct ui_out *uiout)
@@ -11628,7 +11639,7 @@ struct breakpoint_ops base_breakpoint_ops =
   base_breakpoint_resources_needed,
   base_breakpoint_works_in_software_mode,
   base_breakpoint_print_it,
-  NULL,
+  base_breakpoint_print_one,
   base_breakpoint_print_one_detail,
   base_breakpoint_print_mention,
   base_breakpoint_print_recreate,

gdb/breakpoint.h

@@ -608,8 +608,9 @@ struct breakpoint_ops
   enum print_stop_action (*print_it) (struct bpstat *bs);
 
   /* Display information about this breakpoint, for "info
-     breakpoints".  */
-  void (*print_one) (struct breakpoint *, struct bp_location **);
+     breakpoints".  Returns false if this method should use the
+     default behavior.  */
+  bool (*print_one) (struct breakpoint *, struct bp_location **);
 
   /* Display extra information about this breakpoint, below the normal
      breakpoint description in "info breakpoints".