gdb

	* value.h (evaluate_subexpression_type, extract_field_op):
	Declare.
	* printcmd.c (_initialize_printcmd): Use expression_completer for
	'p', 'inspect', 'call'.
	* parser-defs.h (parse_field_expression): Declare.
	* parse.c: Include exceptions.h.
	(in_parse_field, expout_last_struct): New globals.
	(mark_struct_expression): New function.
	(prefixify_expression): Return int.
	(prefixify_subexp): Return int.  Use expout_last_struct.
	(parse_exp_1): Update.
	(parse_exp_in_context): Add 'out_subexp' argument.  Handle
	in_parse_field.
	(parse_field_expression): New function.
	* expression.h (parse_field_expression): Declare.
	(in_parse_field): Likewise.
	* eval.c (evaluate_subexpression_type): New function.
	(extract_field_op): Likewise.
	* completer.h (expression_completer): Declare.
	* completer.c (expression_completer): New function.
	(count_struct_fields, add_struct_fields): New functions.
	* c-exp.y (yyparse): Redefine.
	(COMPLETE): New token.
	(exp): New productions.
	(saw_name_at_eof, last_was_structop): New globals.
	(yylex): Return COMPLETE when needed.  Recognize in_parse_field.
	(c_parse): New function.
	* breakpoint.c (_initialize_breakpoint): Use expression_completer
	for watch, awatch, and rwatch.
	* Makefile.in (parse.o): Depend on exceptions_h.
gdb/testsuite
	* gdb.base/break1.c (struct some_struct): New struct.
	(values): New global.
	* gdb.base/completion.exp: Add field name completion test.
gdb/doc
	* gdb.texinfo (Completion): Add field name example.

1 files changed, 88 insertions, 2 deletions

diff --git a/gdb/completer.c b/gdb/completer.c
index 3d3d34c..163a9dc 100644
--- a/gdb/completer.c
+++ b/gdb/completer.c
@@ -338,6 +338,90 @@ location_completer (char *text, char *word)
   return list;
 }
 
+/* Helper for expression_completer which recursively counts the number
+   of named fields in a structure or union type.  */
+static int
+count_struct_fields (struct type *type)
+{
+  int i, result = 0;
+
+  CHECK_TYPEDEF (type);
+  for (i = 0; i < TYPE_NFIELDS (type); ++i)
+    {
+      if (i < TYPE_N_BASECLASSES (type))
+	result += count_struct_fields (TYPE_BASECLASS (type, i));
+      else if (TYPE_FIELD_NAME (type, i))
+	++result;
+    }
+  return result;
+}
+
+/* Helper for expression_completer which recursively adds field names
+   from TYPE, a struct or union type, to the array OUTPUT.  This
+   function assumes that OUTPUT is correctly-sized.  */
+static void
+add_struct_fields (struct type *type, int *nextp, char **output,
+		   char *fieldname, int namelen)
+{
+  int i;
+
+  CHECK_TYPEDEF (type);
+  for (i = 0; i < TYPE_NFIELDS (type); ++i)
+    {
+      if (i < TYPE_N_BASECLASSES (type))
+	add_struct_fields (TYPE_BASECLASS (type, i), nextp, output,
+			   fieldname, namelen);
+      else if (TYPE_FIELD_NAME (type, i)
+	       && ! strncmp (TYPE_FIELD_NAME (type, i), fieldname, namelen))
+	{
+	  output[*nextp] = xstrdup (TYPE_FIELD_NAME (type, i));
+	  ++*nextp;
+	}
+    }
+}
+
+/* Complete on expressions.  Often this means completing on symbol
+   names, but some language parsers also have support for completing
+   field names.  */
+char **
+expression_completer (char *text, char *word)
+{
+  struct type *type;
+  char *fieldname;
+
+  /* Perform a tentative parse of the expression, to see whether a
+     field completion is required.  */
+  fieldname = NULL;
+  type = parse_field_expression (text, &fieldname);
+  if (fieldname && type)
+    {
+      for (;;)
+	{
+	  CHECK_TYPEDEF (type);
+	  if (TYPE_CODE (type) != TYPE_CODE_PTR
+	      && TYPE_CODE (type) != TYPE_CODE_REF)
+	    break;
+	  type = TYPE_TARGET_TYPE (type);
+	}
+
+      if (TYPE_CODE (type) == TYPE_CODE_UNION
+	  || TYPE_CODE (type) == TYPE_CODE_STRUCT)
+	{
+	  int alloc = count_struct_fields (type);
+	  int flen = strlen (fieldname);
+	  int out = 0;
+	  char **result = (char **) xmalloc ((alloc + 1) * sizeof (char *));
+
+	  add_struct_fields (type, &out, result, fieldname, flen);
+	  result[out] = NULL;
+	  return result;
+	}
+    }
+
+  /* Not ideal but it is what we used to do before... */
+  return location_completer (text, word);
+}
+
 /* Complete on command names.  Used by "help".  */
 char **
 command_completer (char *text, char *word)
@@ -520,7 +604,8 @@ complete_line (const char *text, char *line_buffer, int point)
 		      rl_completer_word_break_characters =
 			gdb_completer_file_name_break_characters;
 		    }
-		  else if (c->completer == location_completer)
+		  else if (c->completer == location_completer
+			   || c->completer == expression_completer)
 		    {
 		      /* Commands which complete on locations want to
 			 see the entire argument.  */
@@ -588,7 +673,8 @@ complete_line (const char *text, char *line_buffer, int point)
 		  rl_completer_word_break_characters =
 		    gdb_completer_file_name_break_characters;
 		}
-	      else if (c->completer == location_completer)
+	      else if (c->completer == location_completer
+		       || c->completer == expression_completer)
 		{
 		  for (p = word;
 		       p > tmp_command