1 files changed, 96 insertions, 0 deletions
diff --git a/tools/wrk/src/units.c b/tools/wrk/src/units.c
new file mode 100644
index 0000000000..b9fc3c0fdf
--- /dev/null
+++ b/tools/wrk/src/units.c
@@ -0,0 +1,96 @@
+// Copyright (C) 2012 - Will Glozer.  All rights reserved.
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <strings.h>
+#include <inttypes.h>
+
+#include "units.h"
+#include "aprintf.h"
+
+typedef struct {
+    int scale;
+    char *base;
+    char *units[];
+} units;
+
+units time_units_us = {
+    .scale = 1000,
+    .base  = "us",
+    .units = { "ms", "s", NULL }
+};
+
+units time_units_s = {
+    .scale = 60,
+    .base  = "s",
+    .units = { "m", "h", NULL }
+};
+
+units binary_units = {
+    .scale = 1024,
+    .base  = "",
+    .units = { "K", "M", "G", "T", "P", NULL }
+};
+
+units metric_units = {
+    .scale = 1000,
+    .base  = "",
+    .units = { "k", "M", "G", "T", "P", NULL }
+};
+
+static char *format_units(long double n, units *m, int p) {
+    long double amt = n, scale;
+    char *unit = m->base;
+    char *msg = NULL;
+
+    scale = m->scale * 0.85;
+
+    for (int i = 0; m->units[i+1] && amt >= scale; i++) {
+        amt /= m->scale;
+        unit = m->units[i];
+    }
+
+    aprintf(&msg, "%.*Lf%s", p, amt, unit);
+
+    return msg;
+}
+
+static int scan_units(char *s, uint64_t *n, units *m) {
+    uint64_t base, scale = 1;
+    char unit[3] = { 0, 0, 0 };
+    int i, c;
+
+    if ((c = sscanf(s, "%"SCNu64"%2s", &base, unit)) < 1) return -1;
+
+    if (c == 2) {
+        for (i = 0; m->units[i] != NULL; i++) {
+            scale *= m->scale;
+            if (!strncasecmp(unit, m->units[i], sizeof(unit))) break;
+        }
+        if (m->units[i] == NULL) return -1;
+    }
+
+    *n = base * scale;
+    return 0;
+}
+
+char *format_binary(long double n) {
+    return format_units(n, &binary_units, 2);
+}
+
+char *format_metric(long double n) {
+    return format_units(n, &metric_units, 2);
+}
+
+char *format_time_us(long double n) {
+    units *units = &time_units_us;
+    if (n >= 1000000.0) {
+        n /= 1000000.0;
+        units = &time_units_s;
+    }
+    return format_units(n, units, 2);
+}
+
+int scan_metric(char *s, uint64_t *n) {
+    return scan_units(s, n, &metric_units);
+}