Re: [PATCH 2/6] gdb: make use of std::string in utils.c

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

On 2021-08-19 5:49 a.m., Andrew Burgess wrote:
> Replace use of manual string management (malloc/free) with std::string
> when creating commands in utils.c.  Things are a little bit messy as
> creating the prefix commands (using add_basic_prefix_cmd and
> add_show_prefix_cmd), don't copy the doc string, while creating the
> actual set/show commands does copy the doc string, this explains the
> extra xstrdup when creating the prefix commands.

Indeed, all of this is really not consistent.  I guess we would need to
create versions of the add_*_cmd that take a
gdb::unique_xmalloc_pointer<char> and set
cmd_list_element::doc_allocated.

> There should be no user visible changes after this commit.
> ---
>  gdb/utils.c | 58 ++++++++++++++++++++++++-----------------------------
>  1 file changed, 26 insertions(+), 32 deletions(-)
> 
> diff --git a/gdb/utils.c b/gdb/utils.c
> index 3916ae5a1c9..143c2eddd70 100644
> --- a/gdb/utils.c
> +++ b/gdb/utils.c
> @@ -508,72 +508,66 @@ add_internal_problem_command (struct internal_problem *problem)
>  {
>    struct cmd_list_element **set_cmd_list;
>    struct cmd_list_element **show_cmd_list;
> -  char *set_doc;
> -  char *show_doc;
>  
>    set_cmd_list = XNEW (struct cmd_list_element *);
>    show_cmd_list = XNEW (struct cmd_list_element *);
>    *set_cmd_list = NULL;
>    *show_cmd_list = NULL;
>  
> -  set_doc = xstrprintf (_("Configure what GDB does when %s is detected."),
> -			problem->name);
> +  std::string set_doc
> +    = string_printf (_("Configure what GDB does when %s is detected."),
> +		       problem->name);
>  
> -  show_doc = xstrprintf (_("Show what GDB does when %s is detected."),
> -			 problem->name);
> +  std::string show_doc
> +    = string_printf (_("Show what GDB does when %s is detected."),
> +		       problem->name);
>  
> -  add_basic_prefix_cmd (problem->name, class_maintenance, set_doc,
> -			set_cmd_list,
> +  add_basic_prefix_cmd (problem->name, class_maintenance,
> +			xstrdup (set_doc.c_str ()), set_cmd_list,
>  			0/*allow-unknown*/, &maintenance_set_cmdlist);
>  
> -  add_show_prefix_cmd (problem->name, class_maintenance, show_doc,
> -		       show_cmd_list,
> +  add_show_prefix_cmd (problem->name, class_maintenance,
> +		       xstrdup (show_doc.c_str ()), show_cmd_list,
>  		       0/*allow-unknown*/, &maintenance_show_cmdlist);

I guess you could keep using xstrprintf for these to avoid the extra
copy...  but what you have LGTM either way.

Simon