C++-ify parse_format_string

This replaces parse_format_string with a class, removing some
constructors along the way.  While doing this, I found that one
argument to gen_printf is unused, so I removed it.

Also, I am not completely sure, but the use of `release' in
maint_agent_printf_command and parse_cmd_to_aexpr seems like it may
leak expressions.

Regression tested by the buildbot.

ChangeLog
2017-12-08  Tom Tromey  <tom@tromey.com>

	* printcmd.c (ui_printf): Update.  Use std::vector.
	* common/format.h (struct format_piece): Add constructor.
	<string>: Now const.
	(class format_pieces): New class.
	(parse_format_string, free_format_pieces)
	(free_format_pieces_cleanup): Remove.
	* common/format.c (format_pieces::format_pieces): Rename from
	parse_format_string.  Update.
	(free_format_pieces, free_format_pieces_cleanup): Remove.
	* breakpoint.c (parse_cmd_to_aexpr): Update.  Use std::vector.
	* ax-gdb.h (gen_printf): Remove argument.
	* ax-gdb.c (gen_printf): Remove "frags" argument.
	(maint_agent_printf_command): Update.  Use std::vector.

gdbserver/ChangeLog
2017-12-08  Tom Tromey  <tom@tromey.com>

	* ax.c (ax_printf): Update.

1 files changed, 4 insertions, 15 deletions

diff --git a/gdb/breakpoint.c b/gdb/breakpoint.c
index 59a4dad..b4353d2 100644
--- a/gdb/breakpoint.c
+++ b/gdb/breakpoint.c
@@ -2226,12 +2226,8 @@ build_target_condition_list (struct bp_location *bl)
 static agent_expr_up
 parse_cmd_to_aexpr (CORE_ADDR scope, char *cmd)
 {
-  struct cleanup *old_cleanups = 0;
-  struct expression **argvec;
   const char *cmdrest;
   const char *format_start, *format_end;
-  struct format_piece *fpieces;
-  int nargs;
   struct gdbarch *gdbarch = get_current_arch ();
 
   if (cmd == NULL)
@@ -2248,9 +2244,7 @@ parse_cmd_to_aexpr (CORE_ADDR scope, char *cmd)
 
   format_start = cmdrest;
 
-  fpieces = parse_format_string (&cmdrest);
-
-  old_cleanups = make_cleanup (free_format_pieces_cleanup, &fpieces);
+  format_pieces fpieces (&cmdrest);
 
   format_end = cmdrest;
 
@@ -2268,17 +2262,14 @@ parse_cmd_to_aexpr (CORE_ADDR scope, char *cmd)
 
   /* For each argument, make an expression.  */
 
-  argvec = (struct expression **) alloca (strlen (cmd)
-					 * sizeof (struct expression *));
-
-  nargs = 0;
+  std::vector<struct expression *> argvec;
   while (*cmdrest != '\0')
     {
       const char *cmd1;
 
       cmd1 = cmdrest;
       expression_up expr = parse_exp_1 (&cmd1, scope, block_for_pc (scope), 1);
-      argvec[nargs++] = expr.release ();
+      argvec.push_back (expr.release ());
       cmdrest = cmd1;
       if (*cmdrest == ',')
 	++cmdrest;
@@ -2292,7 +2283,7 @@ parse_cmd_to_aexpr (CORE_ADDR scope, char *cmd)
     {
       aexpr = gen_printf (scope, gdbarch, 0, 0,
 			  format_start, format_end - format_start,
-			  fpieces, nargs, argvec);
+			  argvec.size (), argvec.data ());
     }
   CATCH (ex, RETURN_MASK_ERROR)
     {
@@ -2302,8 +2293,6 @@ parse_cmd_to_aexpr (CORE_ADDR scope, char *cmd)
     }
   END_CATCH
 
-  do_cleanups (old_cleanups);
-
   /* We have a valid agent expression, return it.  */
   return aexpr;
 }