Re: [PATCH] grep -A/-B/-Cinfinity to get full context
- From
Ramkumar Ramachandra <artagnon@gmail.com>
- Date
- Aug 20, 2010, 13:32 UTC
- Message-ID
- <20100820133206.GD9448@kytes>
- In-Reply-To
- <20100820115527.GR10407@burratino>
Hi Jonathan,
Jonathan Nieder writes:
> Just a proof of concept. > > Cc: René Scharfe <rene.scharfe@lsrfire.ath.cx> > Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Elegant. OPT_INTEGER for integers without the ability to represent infinity, and OPT_INT_INF for integers with definite representation for infinity.
Show 13 quoted lines
> diff --git a/Documentation/technical/api-parse-options.txt b/Documentation/technical/api-parse-options.txt > index 312e3b2..f152a3f 100644 > --- a/Documentation/technical/api-parse-options.txt > +++ b/Documentation/technical/api-parse-options.txt > @@ -160,6 +160,12 @@ There are some macros to easily define options: > Introduce an option with integer argument. > The integer is put into `int_var`. > > +`OPT_INT_INF(short, long, &int_var, inf_val, description)`:: > + Introduce an option with integer argument. > + The integer is put into `int_var`. If the special value > + "inf" (or "infinity") is used as an argument, then `inf_val` > + is put into `int_var`.
Nice. You're making the caller pass the `inf_val` argument - this way, each caller can figure out some integer that's outside its sane range and use that to represent infinity.
Show 8 quoted lines
> - OPT_INTEGER('B', NULL, &opt.pre_context,
> + OPT_INT_INF('B', NULL, &opt.pre_context, -1,
> "show <n> context lines before matches"),
> - OPT_INTEGER('A', NULL, &opt.post_context,
> + OPT_INT_INF('A', NULL, &opt.post_context, -1,
> "show <n> context lines after matches"),
> OPT_NUMBER_CALLBACK(&opt, "shortcut for -C NUM",
> context_callback),For many cases, -1 is probably a good value to choose.
Show 11 quoted lines
> diff --git a/parse-options.h b/parse-options.h
> index 7435cdb..6ae041a 100644
> --- a/parse-options.h
> +++ b/parse-options.h
> @@ -126,6 +126,9 @@ struct option {
> #define OPT_STRING(s, l, v, a, h) { OPTION_STRING, (s), (l), (v), (a), (h) }
> #define OPT_UYN(s, l, v, h) { OPTION_CALLBACK, (s), (l), (v), NULL, \
> (h), PARSE_OPT_NOARG, &parse_opt_tertiary }
> +#define OPT_INT_INF(s, l, v, i, h) \
> + { OPTION_CALLBACK, (s), (l), (v), "n", (h), 0, \
> + parse_opt_infinity_cb, (intptr_t)(i) }Okay, you've used the same character "n" for OPT_INTEGER and OPT_INT_INF.
Thanks for the pleasant reading.
-- Ram