Re: [PATCH 2/3] sequencer: factor out todo command name parsing

["René Scharfe" <l.s.r@web.de>]

Am 25.06.19 um 12:11 schrieb Phillip Wood via GitGitGadget:
> From: Phillip Wood <phillip.wood@dunelm.org.uk>
>
> Factor out the code that parses the name of the command at the start of
> each line in the todo file into it's own function so that it can be used
> in the next commit.

"Factor out" sounds like functionality is intended to not be changed...

>
> Signed-off-by: Phillip Wood <phillip.wood@dunelm.org.uk>
> ---
>  sequencer.c | 19 +++++++++++++------
>  1 file changed, 13 insertions(+), 6 deletions(-)
>
> diff --git a/sequencer.c b/sequencer.c
> index 919e3153f5..793f86bf9a 100644
> --- a/sequencer.c
> +++ b/sequencer.c
> @@ -2076,6 +2076,18 @@ const char *todo_item_get_arg(struct todo_list *todo_list,
>  	return todo_list->buf.buf + item->arg_offset;
>  }
>
> +static int is_command(enum todo_command command, const char **bol)
> +{
> +	const char *str = todo_command_info[command].str;
> +	const char nick = todo_command_info[command].c;
> +	const char *p = *bol + 1;
> +
> +	return skip_prefix(*bol, str, bol) ||
> +		((nick && **bol == nick) &&
> +		 (*p == ' ' || *p == '\t' || *p == '\n' || *p == '\r' || !*p) &&
                                          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
... but this adds support for LF, CR and NUL as separators after short
commands...

> +		 (*bol = p));
> +}
> +
>  static int parse_insn_line(struct repository *r, struct todo_item *item,
>  			   const char *buf, const char *bol, char *eol)
>  {
> @@ -2097,12 +2109,7 @@ static int parse_insn_line(struct repository *r, struct todo_item *item,
>  	}
>
>  	for (i = 0; i < TODO_COMMENT; i++)
> -		if (skip_prefix(bol, todo_command_info[i].str, &bol)) {
> -			item->command = i;
> -			break;
> -		} else if ((bol + 1 == eol || bol[1] == ' ' || bol[1] == '\t') &&
                            ^^^^^^^^^^^^^^
... while this removes the check against the string's length.

Is this safe? It probably (hopefully?) is, as skip_prefix() requires bol
to point to a NUL-terminated string already.

But is_command() could do the old (and shorter) eol check just as well,
so the next question is: Why this change?

> -			   *bol == todo_command_info[i].c) {
> -			bol++;
> +		if (is_command(i, &bol)) {
>  			item->command = i;
>  			break;
>  		}
>