[Piglit] [PATCH 2/2] piglit-util: add piglit_get_microseconds

[Chad Versace]

On 10/17/2013 10:52 AM, Jordan Justen wrote:
> v2:
>   * Use Chad's cmake detection
>   * return value is signed, and a negative indicates an error
>
> Signed-off-by: Jordan Justen <jordan.l.justen at intel.com>
> Cc: Chad Versace <chad.versace at linux.intel.com>
> Cc: Ian Romanick <idr at freedesktop.org>
> ---
>   tests/util/piglit-util.c |   20 ++++++++++++++++++++
>   tests/util/piglit-util.h |   10 ++++++++++
>   2 files changed, 30 insertions(+)
>
> diff --git a/tests/util/piglit-util.c b/tests/util/piglit-util.c
> index 71d55a7..8836978 100644
> --- a/tests/util/piglit-util.c
> +++ b/tests/util/piglit-util.c
> @@ -33,6 +33,10 @@
>   #include <string.h>
>   #include <errno.h>
>
> +#ifdef PIGLIT_HAS_POSIX_CLOCK_MONOTONIC
> +#include <time.h>
> +#endif
> +
>   #include "config.h"
>   #if defined(HAVE_SYS_TIME_H) && defined(HAVE_SYS_RESOURCE_H) && defined(HAVE_SETRLIMIT)
>   #include <sys/time.h>
> @@ -462,3 +466,19 @@ write_null:
>   	va_end(va);
>   	return size_written;
>   }
> +
> +int64_t
> +piglit_get_microseconds(void)
> +{
> +#ifdef PIGLIT_HAS_POSIX_CLOCK_MONOTONIC
> +	struct timespec t;
> +	int r = clock_gettime(CLOCK_MONOTONIC, &t);
> +	if (r >= 0)
> +		return (t.tv_sec * 1000000) + (t.tv_nsec / 1000);
> +	else
> +		return -1LL;
> +#else
> +	return (int64_t) -1;
> +#endif
> +}

The two occurrences of `return -1` should appear symmetric, otherwise it
looks like the code is doing different things at each occurrence.

I don't think there's any need for the int64_t cast, but I'm not confident
of that. Do you get a warning if you remove that?

Anways, please make the returns look symmetric and this has my r-b. I think
piglit_get_microseconds() is much less cumbersome to use than the Posix
clock functions.