On Thu, Oct 01, 2020 at 06:43:20PM +0200, Philippe Mathieu-Daudé wrote:
> Introduce freq_to_str() to convert frequency values in human
> friendly units using the SI units for Hertz.
>
> Suggested-by: Luc Michel <l...@lmichel.fr>
> Signed-off-by: Philippe Mathieu-Daudé <f4...@amsat.org>
> ---
> include/qemu/cutils.h | 12 ++++++++++++
> util/cutils.c | 14 ++++++++++++++
> 2 files changed, 26 insertions(+)
>
> diff --git a/include/qemu/cutils.h b/include/qemu/cutils.h
> index 3a86ec0321..4bbf4834ea 100644
> --- a/include/qemu/cutils.h
> +++ b/include/qemu/cutils.h
> @@ -158,6 +158,18 @@ int qemu_strtosz_metric(const char *nptr, const char
> **end, uint64_t *result);
>
> char *size_to_str(uint64_t val);
>
> +/**
> + * freq_to_str:
> + * @freq_hz: frequency to stringify
> + *
> + * Return human readable string for frequency @freq_hz.
> + * Use SI units like KHz, MHz, and so forth.
> + *
> + * The caller is responsible for releasing the value returned
> + * with g_free() after use.
> + */
> +char *freq_to_str(uint64_t freq_hz);
> +
> /* used to print char* safely */
> #define STR_OR_NULL(str) ((str) ? (str) : "null")
>
> diff --git a/util/cutils.c b/util/cutils.c
> index 8da34e04b0..be4e43a9ef 100644
> --- a/util/cutils.c
> +++ b/util/cutils.c
> @@ -885,6 +885,20 @@ char *size_to_str(uint64_t val)
> return g_strdup_printf("%0.3g %sB", (double)val / div, suffixes[i]);
> }
>
> +char *freq_to_str(uint64_t freq_hz)
> +{
> + static const char *const suffixes[] = { "", "K", "M", "G", "T", "P", "E"
> };
> + double freq = freq_hz;
> + size_t idx = 0;
> +
> + while (freq >= 1000.0 && idx < ARRAY_SIZE(suffixes)) {
> + freq /= 1000.0;
> + idx++;
> + }
> +
> + return g_strdup_printf("%0.3g %sHz", freq, suffixes[idx]);
The only thing protecting this from out of bounds array access is
the fact that UINT64_MAX is smaller than 1000E. I wonder if this
causes a Coverity warning.
> +}
> +
> int qemu_pstrcmp0(const char **str1, const char **str2)
> {
> return g_strcmp0(*str1, *str2);
> --
> 2.26.2
>
--
Eduardo
