Re: [PATCH v6 2/5] Add support to catch groups of syscalls.

Sergio Durigan Junior
2016-05-26T18:17:37Z

On Thursday, May 19 2016, Gabriel Krisman Bertazi wrote:

> This implements the catchpoint side. While parsing 'catch syscall'
> arguments, we verify if the argument is a syscall group and expand it to
> a list of syscalls that are part of that group.

Thanks for the patch.

> gdb/
>
> * break-catch-syscall.c (catch_syscall_split_args): Verify if
> argument is a syscall group and expand it to a list of syscalls
> when creating catchpoints.
> (catch_syscall_completer): Add word completion for system call
> groups.
> ---
> gdb/break-catch-syscall.c | 93 ++++++++++++++++++++++++++++++++++++++++++-----
> 1 file changed, 84 insertions(+), 9 deletions(-)
>
> diff --git a/gdb/break-catch-syscall.c b/gdb/break-catch-syscall.c
> index dbebdda..c564b8f 100644
> --- a/gdb/break-catch-syscall.c
> +++ b/gdb/break-catch-syscall.c
> @@ -464,10 +464,38 @@ catch_syscall_split_args (char *arg)
> cur_name[i] = '\0';
> arg += i;
>
> - /* Check if the user provided a syscall name or a number. */
> + /* Check if the user provided a syscall name, group, or a number. */
> syscall_number = (int) strtol (cur_name, &endptr, 0);
> if (*endptr == '\0')
> - get_syscall_by_number (gdbarch, syscall_number, &s);
> + {
> + get_syscall_by_number (gdbarch, syscall_number, &s);
> + VEC_safe_push (int, result, s.number);
> + }
> + else if (startswith (cur_name, "g:")
> + || startswith (cur_name, "group:"))
> + {
> + /* We have a syscall group. Let's expand it into a syscall
> + list before inserting. */
> + struct syscall *syscall_list;
> + const char *group_name;
> +
> + /* Skip over "g:" and "group:" prefix strings. */
> + group_name = strchr (cur_name, ':') + 1;
> +
> + syscall_list = get_syscalls_by_group (gdbarch, group_name);
> +
> + if (syscall_list == NULL)
> + error (_("Unknown syscall group '%s'."), group_name);
> +
> + for (i = 0; syscall_list[i].name != NULL; i++)
> + {
> + /* Insert each syscall that are part of the group. No
> + need to check if it is valid. */
> + VEC_safe_push (int, result, syscall_list[i].number);
> + }
> +
> + xfree (syscall_list);
> + }
> else
> {
> /* We have a name. Let's check if it's valid and convert it
> @@ -479,10 +507,10 @@ catch_syscall_split_args (char *arg)
> because GDB cannot do anything useful if there's no
> syscall number to be caught. */
> error (_("Unknown syscall name '%s'."), cur_name);
> - }
>
> - /* Ok, it's valid. */
> - VEC_safe_push (int, result, s.number);
> + /* Ok, it's valid. */
> + VEC_safe_push (int, result, s.number);
> + }
> }
>
> discard_cleanups (cleanup);
> @@ -597,11 +625,58 @@ static VEC (char_ptr) *
> catch_syscall_completer (struct cmd_list_element *cmd,
> const char *text, const char *word)
> {
> - const char **list = get_syscall_names (get_current_arch ());
> - VEC (char_ptr) *retlist
> - = (list == NULL) ? NULL : complete_on_enum (list, word, word);
> + struct gdbarch *gdbarch = get_current_arch ();
> + struct cleanup *cleanups = make_cleanup (null_cleanup, NULL);
> + VEC (char_ptr) *group_retlist = NULL;
> + VEC (char_ptr) *syscall_retlist = NULL;
> + VEC (char_ptr) *retlist = NULL;
> + const char **group_list = NULL;
> + const char **syscall_list = NULL;
> + const char *prefix;
> + int i;
> +
> + /* Completion considers ':' to be a word separator, so we use this to
> + verify whether the previous word was a group prefix. If so, we
> + build the completion list using group names only. */
> + for (prefix = word; prefix != text && prefix[-1] != ' '; prefix--)
> + ;
> +
> + if (startswith (prefix, "g:") || startswith (prefix, "group:"))
> + {
> + /* Perform completion inside 'group:' namespace only. */
> + group_list = get_syscall_group_names (gdbarch);
> + retlist = (group_list == NULL
> + ? NULL : complete_on_enum (group_list, word, word));
> + }
> + else
> + {
> + /* Complete with both, syscall names and groups. */
> + syscall_list = get_syscall_names (gdbarch);
> + group_list = get_syscall_group_names (gdbarch);
> +
> + /* Append "group:" prefix to syscall groups. */
> + for (i = 0; group_list[i] != NULL; i++)
> + {
> + char *prefixed_group = xstrprintf ("group:%s", group_list[i]);
> +
> + group_list[i] = prefixed_group;
> + make_cleanup (xfree, prefixed_group);
> + }
> +
> + syscall_retlist = ((syscall_list == NULL)
> + ? NULL : complete_on_enum (syscall_list, word, word));
> + group_retlist = ((group_list == NULL)
> + ? NULL : complete_on_enum (group_list, word, word));
> +
> + retlist = VEC_merge (char_ptr, syscall_retlist, group_retlist);
> + }
> +
> + VEC_free (char_ptr, syscall_retlist);
> + VEC_free (char_ptr, group_retlist);
> + xfree (syscall_list);
> + xfree (group_list);
> + do_cleanups (cleanups);
>
> - xfree (list);
> return retlist;
> }
>
> --
> 2.4.11

LGTM.

--
Sergio
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