Re: [PATCH v5 2/5] Add support to catch groups of syscalls.

[Doug Evans <dje@google.com>]

Gabriel Krisman Bertazi writes:
  > 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.
  >
  > 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.

Hi.
Just more nits.

  > diff --git a/gdb/break-catch-syscall.c b/gdb/break-catch-syscall.c
  > index dbebdda..be034ac 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 (strncmp (cur_name, "g:", sizeof ("g:") - 1) == 0
  > +	       || strncmp (cur_name, "group:", sizeof ("group:") - 1) == 0)

Use startswith here.
[See common/common-utils.h.]

  > +	{
  > +	  /* 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 +625,59 @@ 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 (strncmp (prefix, "g:", sizeof ("g:") - 1) == 0
  > +      || strncmp (prefix, "group:", sizeof ("group:") - 1) == 0)

startswith

  > +    {
  > +      /* 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;
  >  }
  >
  > --
  > 2.4.3
  >