Subject: Re: [PATCH v6 2/2] t5560-http-backend-noserver.sh: add CONTENT_LENGTH cases

From: Junio C Hamano <[email-masked]>
Date: Mon, 27 Nov 2017 09:29:20 +0900

Max Kirillov <[email-masked]> writes:

> Add tests for cases:
>
> * CONTENT_LENGTH is set, script's stdin has more data.
>   (Failure would make it read GIT_HTTP_MAX_REQUEST_BUFFER bytes from /dev/zero
>   and fail. It does not seem to cause any performance issues with the default
>   value of GIT_HTTP_MAX_REQUEST_BUFFER.)
> * CONTENT_LENGTH is specified to a value which does not fix into ssize_t.

s/fix/fit/ you meant?

> diff --git a/t/helper/test-print-values.c b/t/helper/test-print-values.c
> new file mode 100644
> index 0000000000..8f7e5af319
> --- /dev/null
> +++ b/t/helper/test-print-values.c
> @@ -0,0 +1,10 @@
> +#include <stdio.h>
> +#include <string.h>
> +
> +int cmd_main(int argc, const char **argv)
> +{
> +	if (argc == 2 && strcmp(argv[1], "(size_t)(-20)") == 0)
> +		printf("%zu", (ssize_t)(-20));
> +
> +	return 0;
> +}

As far as I know, we avoid %zu (C99), as it may not be safe yet to
do so on all platforms.

e.g. c.f. https://public-inbox.org/git/[email-masked]/

You may want to double check the 1/2 of this topic, too.

Forcing a test command line to spell out "(size_t)(-20)" feels a bit
atrocious, especially given that this program is capable of ever
showing that string and nothing else, and it does not even diagnose
typos as errors.

I wonder if we would want to have "test-print-larger-than-ssize" and
do something like

    #include "cache.h"

    int cmd_main(int ac, const char **av)
    {
            uintmax_t large = ((uintmax_t) SSIZE_MAX) + 1;

            printf("%" PRIuMAX "\n", large);
            return 0;
    }

perhaps?

Note that wrapper.c seems to assume that not everybody has
SSIZE_MAX, so we might have to do something silly like

	size_t large = ~0;
	large = ~(large & ~(large >> 1)) + 1;

        printf("%" PRIuMAX "\n", (uintmax_t) large);

just to be careful (even though we now assume 2's complement),
though.