Simplify psym_map_matching_symbols

This introduces a new helper function,
iterate_over_symbols_terminated, and changes psym_map_matching_symbols
to use it.  A subsequent patch will introduce a new user of this
function in the DWARF reader.

gdb/ChangeLog
2019-09-10  Tom Tromey  <tromey@adacore.com>

	* psymtab.c (map_block): Remove.
	(psym_map_matching_symbols): Use iterate_over_symbols_terminated.
	* symtab.c (iterate_over_symbols_terminated): New function.
	* symtab.c (iterate_over_symbols_terminated): Declare.

gdb/ChangeLog

@@ -1,3 +1,10 @@
+2019-09-10  Tom Tromey  <tromey@adacore.com>
+
+	* psymtab.c (map_block): Remove.
+	(psym_map_matching_symbols): Use iterate_over_symbols_terminated.
+	* symtab.c (iterate_over_symbols_terminated): New function.
+	* symtab.c (iterate_over_symbols_terminated): Declare.
+
 2019-09-10  Tom Tromey  <tromey@adacore.com>
 
 	* ada-lang.c (ada_iterate_over_symbols): Return bool.

gdb/psymtab.c

@@ -1168,38 +1168,6 @@ psymtab_to_fullname (struct partial_symtab *ps)
   return ps->fullname;
 }
 
-/* For all symbols, s, in BLOCK that are in DOMAIN and match NAME
-   according to the function MATCH, call CALLBACK(BLOCK, s, DATA).
-   BLOCK is assumed to come from OBJFILE.  Returns false iff CALLBACK
-   ever returns false, and otherwise returns true.  */
-
-static bool
-map_block (const char *name, domain_enum domain, struct objfile *objfile,
-	   const struct block *block,
-	   gdb::function_view<symbol_found_callback_ftype> callback,
-	   symbol_name_match_type match)
-{
-  struct block_iterator iter;
-  struct symbol *sym;
-
-  lookup_name_info lookup_name (name, match);
-
-  for (sym = block_iter_match_first (block, lookup_name, &iter);
-       sym != NULL;
-       sym = block_iter_match_next (lookup_name, &iter))
-    {
-      if (symbol_matches_domain (SYMBOL_LANGUAGE (sym),
-				 SYMBOL_DOMAIN (sym), domain))
-	{
-	  struct block_symbol block_sym = {sym, block};
-	  if (!callback (&block_sym))
-	    return false;
-	}
-    }
-
-  return true;
-}
-
 /* Psymtab version of map_matching_symbols.  See its definition in
    the definition of quick_symbol_functions in symfile.h.  */
 
@@ -1214,6 +1182,8 @@ psym_map_matching_symbols
 {
   const int block_kind = global ? GLOBAL_BLOCK : STATIC_BLOCK;
 
+  lookup_name_info lookup_name (name, match);
+
   for (partial_symtab *ps : require_partial_symbols (objfile, 1))
     {
       QUIT;
@@ -1227,10 +1197,8 @@ psym_map_matching_symbols
 	  if (cust == NULL)
 	    continue;
 	  block = BLOCKVECTOR_BLOCK (COMPUNIT_BLOCKVECTOR (cust), block_kind);
-	  if (!map_block (name, domain, objfile, block, callback, match))
+	  if (!iterate_over_symbols_terminated (block, lookup_name,
-	    return;
+						domain, callback))
-	  struct block_symbol block_sym = {nullptr, block};
-	  if (!callback (&block_sym))
 	    return;
 	}
     }

gdb/symtab.c

@@ -2847,6 +2847,21 @@ iterate_over_symbols (const struct block *block,
   return true;
 }
 
+/* See symtab.h.  */
+
+bool
+iterate_over_symbols_terminated
+  (const struct block *block,
+   const lookup_name_info &name,
+   const domain_enum domain,
+   gdb::function_view<symbol_found_callback_ftype> callback)
+{
+  if (!iterate_over_symbols (block, name, domain, callback))
+    return false;
+  struct block_symbol block_sym = {nullptr, block};
+  return callback (&block_sym);
+}
+
 /* Find the compunit symtab associated with PC and SECTION.
    This will read in debug info as necessary.  */
 

gdb/symtab.h

@@ -2106,6 +2106,16 @@ bool iterate_over_symbols (const struct block *block,
 			   const domain_enum domain,
 			   gdb::function_view<symbol_found_callback_ftype> callback);
 
+/* Like iterate_over_symbols, but if all calls to CALLBACK return
+   true, then calls CALLBACK one additional time with a block_symbol
+   that has a valid block but a NULL symbol.  */
+
+bool iterate_over_symbols_terminated
+  (const struct block *block,
+   const lookup_name_info &name,
+   const domain_enum domain,
+   gdb::function_view<symbol_found_callback_ftype> callback);
+
 /* Storage type used by demangle_for_lookup.  demangle_for_lookup
    either returns a const char * pointer that points to either of the
    fields of this type, or a pointer to the input NAME.  This is done