Introduce gdb_argv, a class wrapper for buildargv

This introduces gdb_argv, a class wrapping an "argv" pointer; that is,
a pointer to a NULL-terminated array of char*, where both the array
and each non-NULL element in the array are xmalloc'd.

This patch then changes most users of gdb_buildargv to use gdb_argv
instead.

ChangeLog
2017-08-03  Tom Tromey  <tom@tromey.com>

	* utils.h (struct gdb_argv_deleter): New.
	(gdb_argv): New class.
	* utils.c (gdb_argv::reset): New method.
	* tracepoint.c (delete_trace_variable_command): Use gdb_argv.
	* tracefile.c (tsave_command): Use gdb_argv.
	* top.c (new_ui_command): Use gdb_argv.
	* symmisc.c (maintenance_print_symbols)
	(maintenance_print_msymbols, maintenance_expand_symtabs): Use gdb_argv.
	* symfile.c (symbol_file_command, generic_load)
	(remove_symbol_file_command): Use gdb_argv.
	* stack.c (backtrace_command): Use gdb_argv.
	* source.c (add_path, show_substitute_path_command)
	(unset_substitute_path_command, set_substitute_path_command):
	Use gdb_argv.
	* skip.c (skip_command): Use gdb_argv.  Use gdb_buildargv.
	* ser-mingw.c (pipe_windows_open): Use gdb_argv.
	* remote.c (extended_remote_run, remote_put_command)
	(remote_get_command, remote_delete_command): Use gdb_argv.
	* remote-sim.c (gdbsim_load, gdbsim_create_inferior)
	(gdbsim_open): Use gdb_argv.
	* python/py-cmd.c (gdbpy_string_to_argv): Use gdb_argv.
	* psymtab.c (maintenance_print_psymbols): Use gdb_argv.
	* procfs.c (procfs_info_proc): Use gdb_argv.
	* interps.c (interpreter_exec_cmd): Use gdb_argv.
	* infrun.c (handle_command): Use gdb_argv.
	* inferior.c (add_inferior_command, clone_inferior_command):
	Use gdb_argv.
	* guile/scm-string.c (gdbscm_string_to_argv): Use gdb_argv.
	* exec.c (exec_file_command): Use gdb_argv.
	* cli/cli-cmds.c (alias_command): Use gdb_argv.
	* compile/compile.c (build_argc_argv): Use gdb_argv.

1 files changed, 13 insertions, 18 deletions

diff --git a/gdb/cli/cli-cmds.c b/gdb/cli/cli-cmds.c
index a0d566b..036a2f0 100644
--- a/gdb/cli/cli-cmds.c
+++ b/gdb/cli/cli-cmds.c
@@ -1400,31 +1400,27 @@ alias_command (char *args, int from_tty)
 {
   int i, alias_argc, command_argc;
   int abbrev_flag = 0;
-  char *args2, *equals;
+  char *equals;
   const char *alias, *command;
-  char **alias_argv, **command_argv;
-  struct cleanup *cleanup;
 
   if (args == NULL || strchr (args, '=') == NULL)
     alias_usage_error ();
 
-  args2 = xstrdup (args);
-  cleanup = make_cleanup (xfree, args2);
-  equals = strchr (args2, '=');
-  *equals = '\0';
-  alias_argv = gdb_buildargv (args2);
-  make_cleanup_freeargv (alias_argv);
-  command_argv = gdb_buildargv (equals + 1);
-  make_cleanup_freeargv (command_argv);
+  equals = strchr (args, '=');
+  std::string args2 (args, equals - args);
+
+  gdb_argv built_alias_argv (args2.c_str ());
+  gdb_argv command_argv (equals + 1);
 
-  for (i = 0; alias_argv[i] != NULL; )
+  char **alias_argv = built_alias_argv.get ();
+  while (alias_argv[0] != NULL)
     {
-      if (strcmp (alias_argv[i], "-a") == 0)
+      if (strcmp (alias_argv[0], "-a") == 0)
 	{
 	  ++alias_argv;
 	  abbrev_flag = 1;
 	}
-      else if (strcmp (alias_argv[i], "--") == 0)
+      else if (strcmp (alias_argv[0], "--") == 0)
 	{
 	  ++alias_argv;
 	  break;
@@ -1449,12 +1445,13 @@ alias_command (char *args, int from_tty)
     }
 
   alias_argc = countargv (alias_argv);
-  command_argc = countargv (command_argv);
+  command_argc = command_argv.count ();
 
   /* COMMAND must exist.
      Reconstruct the command to remove any extraneous spaces,
      for better error messages.  */
-  std::string command_string (argv_to_string (command_argv, command_argc));
+  std::string command_string (argv_to_string (command_argv.get (),
+					      command_argc));
   command = command_string.c_str ();
   if (! valid_command_p (command))
     error (_("Invalid command to alias to: %s"), command);
@@ -1511,8 +1508,6 @@ alias_command (char *args, int from_tty)
 		     command_argv[command_argc - 1],
 		     class_alias, abbrev_flag, c_command->prefixlist);
     }
-
-  do_cleanups (cleanup);
 }
 
 /* Print a list of files and line numbers which a user may choose from