Re: [RFC/PATCH v3] merge-base: teach "git merge-base" to accept more than 2 arguments

> Before this patch "git merge-base" accepted only 2 arguments, so
> only merge bases between 2 references could be computed.
>
> The purpose of this patch is to make "git merge-base" accept more
> than 2 arguments, so that the merge bases between the first given
> reference and all the other references can be computed.

> +static struct commit *get_commit_reference(const char *arg)
> +{
> +	unsigned char revkey[20];
> +	if (get_sha1(arg, revkey))
> +		die("Not a valid object name %s", arg);
> +	return lookup_commit_reference(revkey);
> +}

>  int cmd_merge_base(int argc, const char **argv, const char *prefix)
>  {
> +	struct commit **rev;
>  	int show_all = 0;
> +	int rev_nr = 0;
>  
>  	git_config(git_default_config, NULL);
>  
> @@ -38,15 +48,18 @@ int cmd_merge_base(int argc, const char **argv, const char *prefix)
>  			usage(merge_base_usage);
>  		argc--; argv++;
>  	}
> +	if (argc < 3)
>  		usage(merge_base_usage);
> +
> +	rev = xmalloc((argc - 1) * sizeof(*rev));
> +
> +	do {
> +		struct commit *r = get_commit_reference(argv[1]);
> +		if (!r)
> +			return 1;