Re: [RFA 3/3] Remove cleanups from break-catch-syscall.c

[Simon Marchi <simon.marchi@polymtl.ca>]

On 2017-10-18 00:06, Tom Tromey wrote:
> This removes the remaining cleanups from break-catch-syscall.c by
> storing temporary strings in a vector.
> 
> ChangeLog
> 2017-10-17  Tom Tromey  <tom@tromey.com>
> 
> 	* break-catch-syscall.c (catch_syscall_completer): Use
> 	std::string, gdb::unique_xmalloc_ptr.
> ---
>  gdb/ChangeLog             |  5 +++++
>  gdb/break-catch-syscall.c | 35 ++++++++++++++++++-----------------
>  2 files changed, 23 insertions(+), 17 deletions(-)
> 
> diff --git a/gdb/break-catch-syscall.c b/gdb/break-catch-syscall.c
> index 01e761ce37..2bbfee0ac4 100644
> --- a/gdb/break-catch-syscall.c
> +++ b/gdb/break-catch-syscall.c
> @@ -560,9 +560,7 @@ catch_syscall_completer (struct cmd_list_element 
> *cmd,
>                           const char *text, const char *word)
>  {
>    struct gdbarch *gdbarch = get_current_arch ();
> -  struct cleanup *cleanups = make_cleanup (null_cleanup, NULL);
> -  const char **group_list = NULL;
> -  const char **syscall_list = NULL;
> +  gdb::unique_xmalloc_ptr<const char *> group_list;
>    const char *prefix;
>    int i;
> 
> @@ -575,34 +573,37 @@ catch_syscall_completer (struct cmd_list_element 
> *cmd,
>    if (startswith (prefix, "g:") || startswith (prefix, "group:"))
>      {
>        /* Perform completion inside 'group:' namespace only.  */
> -      group_list = get_syscall_group_names (gdbarch);
> +      group_list.reset (get_syscall_group_names (gdbarch));
>        if (group_list != NULL)
> -	complete_on_enum (tracker, group_list, word, word);
> +	complete_on_enum (tracker, group_list.get (), word, word);
>      }
>    else
>      {
>        /* Complete with both, syscall names and groups.  */
> -      syscall_list = get_syscall_names (gdbarch);
> -      group_list = get_syscall_group_names (gdbarch);
> +      gdb::unique_xmalloc_ptr<const char *> syscall_list
> +	(get_syscall_names (gdbarch));
> +      group_list.reset (get_syscall_group_names (gdbarch));
> +
> +      const char **group_ptr = group_list.get ();
> +
> +      /* Hold on to strings while we're using them.  */
> +      std::vector<std::string> holders;
> 
>        /* Append "group:" prefix to syscall groups.  */
> -      for (i = 0; group_list[i] != NULL; i++)
> +      for (i = 0; group_ptr[i] != NULL; i++)
>  	{
> -	  char *prefixed_group = xstrprintf ("group:%s", group_list[i]);
> +	  std::string prefixed_group = string_printf ("group:%s",
> +						      group_ptr[i]);
> 
> -	  group_list[i] = prefixed_group;
> -	  make_cleanup (xfree, prefixed_group);
> +	  group_ptr[i] = prefixed_group.c_str ();
> +	  holders.push_back (prefixed_group);

Maybe an opportunity to std::move?  Alternatively:

   holders.emplace_back (string_printf ("group:%s", group_ptr[i]));
   group_ptr[i] = holders.back ().c_str ();

LGTM in any case, as well as the two previous patches.

Simon