Re: [RFC PATCH 1/3] usage: extract `prefix_suffix_lines()` from `advise()`

[Junio C Hamano <gitster@pobox.com>]

Martin Ågren <martin.agren@gmail.com> writes:

> I'm open for suggestions on the naming of `prefix_suffix_lines()`...

Is there a verb that means "have/place the thing in between two
other things" or "Bring two things and place them on each side of
the third thing" in a more concise way?  Wrap?  Sandwich?  Enclose?

> +
> +/*
> + * Write the message to the file, prefixing and suffixing
> + * each line with `prefix` resp. `suffix`.
> + */
> +void prefix_suffix_lines(FILE *f, const char *prefix,
> +			 const char *message, const char *suffix);
> +
> ...
> diff --git a/usage.c b/usage.c
> index cdd534c9df..80f9c1d14b 100644
> --- a/usage.c
> +++ b/usage.c
> @@ -6,6 +6,24 @@
>  #include "git-compat-util.h"
>  #include "cache.h"
>  
> +void prefix_suffix_lines(FILE *f,
> +			 const char *prefix,
> +			 const char *message,
> +			 const char *suffix)
> +{
> +	const char *cp, *np;
> +
> +	for (cp = message; *cp; cp = np) {
> +		np = strchrnul(cp, '\n');
> +		fprintf(f, "%s%.*s%s\n",
> +			prefix,
> +			(int)(np - cp), cp,
> +			suffix);
> +		if (*np)
> +			np++;
> +	}
> +}
> +
>  void vreportf(const char *prefix, const char *err, va_list params)
>  {
>  	char msg[4096];

I guess we can directly use this even in the codepath that
implements die() without having to worry about the helper making any
extra allocation, which is good.