From 22951aaaebb6c4c314c58ad576960a9c57695bbc Mon Sep 17 00:00:00 2001 From: Peter Xu Date: Fri, 12 May 2017 12:17:40 +0800 Subject: [PATCH] utils: provide size_to_str() Moving the algorithm from print_type_size() into size_to_str() so that other component can also leverage it. With that, refactor print_type_size(). The assert() in that logic is removed though, since even UINT64_MAX would not overflow. Signed-off-by: Peter Xu Message-Id: <1494562661-9063-3-git-send-email-peterx@redhat.com> Reviewed-by: Markus Armbruster Signed-off-by: Dr. David Alan Gilbert --- include/qemu-common.h | 1 + qapi/string-output-visitor.c | 22 ++++++---------------- util/cutils.c | 25 +++++++++++++++++++++++++ 3 files changed, 32 insertions(+), 16 deletions(-) diff --git a/include/qemu-common.h b/include/qemu-common.h index d218821c14..387ef520bf 100644 --- a/include/qemu-common.h +++ b/include/qemu-common.h @@ -145,6 +145,7 @@ void qemu_hexdump(const char *buf, FILE *fp, const char *prefix, size_t size); int parse_debug_env(const char *name, int max, int initial); const char *qemu_ether_ntoa(const MACAddr *mac); +char *size_to_str(uint64_t val); void page_size_init(void); /* returns non-zero if dump is in progress, otherwise zero is diff --git a/qapi/string-output-visitor.c b/qapi/string-output-visitor.c index 94ac8211d1..53c2175d81 100644 --- a/qapi/string-output-visitor.c +++ b/qapi/string-output-visitor.c @@ -211,10 +211,8 @@ static void print_type_size(Visitor *v, const char *name, uint64_t *obj, Error **errp) { StringOutputVisitor *sov = to_sov(v); - static const char suffixes[] = { 'B', 'K', 'M', 'G', 'T', 'P', 'E' }; - uint64_t div, val; - char *out; - int i; + uint64_t val; + char *out, *psize; if (!sov->human) { out = g_strdup_printf("%"PRIu64, *obj); @@ -223,19 +221,11 @@ static void print_type_size(Visitor *v, const char *name, uint64_t *obj, } val = *obj; - - /* The exponent (returned in i) minus one gives us - * floor(log2(val * 1024 / 1000). The correction makes us - * switch to the higher power when the integer part is >= 1000. - */ - frexp(val / (1000.0 / 1024.0), &i); - i = (i - 1) / 10; - assert(i < ARRAY_SIZE(suffixes)); - div = 1ULL << (i * 10); - - out = g_strdup_printf("%"PRIu64" (%0.3g %c%s)", val, - (double)val/div, suffixes[i], i ? "iB" : ""); + psize = size_to_str(val); + out = g_strdup_printf("%"PRIu64" (%s)", val, psize); string_output_set(sov, out); + + g_free(psize); } static void print_type_bool(Visitor *v, const char *name, bool *obj, diff --git a/util/cutils.c b/util/cutils.c index 50ad179dc5..1534682083 100644 --- a/util/cutils.c +++ b/util/cutils.c @@ -619,3 +619,28 @@ const char *qemu_ether_ntoa(const MACAddr *mac) return ret; } + +/* + * Return human readable string for size @val. + * @val can be anything that uint64_t allows (no more than "16 EiB"). + * Use IEC binary units like KiB, MiB, and so forth. + * Caller is responsible for passing it to g_free(). + */ +char *size_to_str(uint64_t val) +{ + static const char *suffixes[] = { "", "Ki", "Mi", "Gi", "Ti", "Pi", "Ei" }; + unsigned long div; + int i; + + /* + * The exponent (returned in i) minus one gives us + * floor(log2(val * 1024 / 1000). The correction makes us + * switch to the higher power when the integer part is >= 1000. + * (see e41b509d68afb1f for more info) + */ + frexp(val / (1000.0 / 1024.0), &i); + i = (i - 1) / 10; + div = 1ULL << (i * 10); + + return g_strdup_printf("%0.3g %sB", (double)val / div, suffixes[i]); +}