From cfb344892209783a600e80053dba1cfeee4bd16a Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Wed, 25 May 2022 15:38:48 +0200 Subject: cutils: add functions for IEC and SI prefixes Extract the knowledge of IEC and SI prefixes out of size_to_str and freq_to_str, so that it can be reused when printing statistics. Signed-off-by: Paolo Bonzini --- util/cutils.c | 34 +++++++++++++++++++++++++--------- 1 file changed, 25 insertions(+), 9 deletions(-) (limited to 'util') diff --git a/util/cutils.c b/util/cutils.c index a58bcfd..6d04e52 100644 --- a/util/cutils.c +++ b/util/cutils.c @@ -872,6 +872,25 @@ int parse_debug_env(const char *name, int max, int initial) return debug; } +const char *si_prefix(unsigned int exp10) +{ + static const char *prefixes[] = { + "a", "f", "p", "n", "u", "m", "", "K", "M", "G", "T", "P", "E" + }; + + exp10 += 18; + assert(exp10 % 3 == 0 && exp10 / 3 < ARRAY_SIZE(prefixes)); + return prefixes[exp10 / 3]; +} + +const char *iec_binary_prefix(unsigned int exp2) +{ + static const char *prefixes[] = { "", "Ki", "Mi", "Gi", "Ti", "Pi", "Ei" }; + + assert(exp2 % 10 == 0 && exp2 / 10 < ARRAY_SIZE(prefixes)); + return prefixes[exp2 / 10]; +} + /* * Return human readable string for size @val. * @val can be anything that uint64_t allows (no more than "16 EiB"). @@ -880,7 +899,6 @@ int parse_debug_env(const char *name, int max, int initial) */ char *size_to_str(uint64_t val) { - static const char *suffixes[] = { "", "Ki", "Mi", "Gi", "Ti", "Pi", "Ei" }; uint64_t div; int i; @@ -891,25 +909,23 @@ char *size_to_str(uint64_t val) * (see e41b509d68afb1f for more info) */ frexp(val / (1000.0 / 1024.0), &i); - i = (i - 1) / 10; - div = 1ULL << (i * 10); + i = (i - 1) / 10 * 10; + div = 1ULL << i; - return g_strdup_printf("%0.3g %sB", (double)val / div, suffixes[i]); + return g_strdup_printf("%0.3g %sB", (double)val / div, iec_binary_prefix(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; + size_t exp10 = 0; while (freq >= 1000.0) { freq /= 1000.0; - idx++; + exp10 += 3; } - assert(idx < ARRAY_SIZE(suffixes)); - return g_strdup_printf("%0.3g %sHz", freq, suffixes[idx]); + return g_strdup_printf("%0.3g %sHz", freq, si_prefix(exp10)); } int qemu_pstrcmp0(const char **str1, const char **str2) -- cgit v1.1