Merge branch 'evelu-peak' of https://github.com/ErwanAliasr1/fio

[fio.git] / lib / num2str.c

diff --git a/lib/num2str.c b/lib/num2str.c
index 0ed05f33ea8039b52f5c18a7574ef78adb4caac6..cd89a0e59171291017ece4429bc70b4e43eb95ca 100644 (file)
--- a/lib/num2str.c
+++ b/lib/num2str.c
@@ -1,78 +1,120 @@
+#include <assert.h>
 #include <stdlib.h>
 #include <stdio.h>
 #include <string.h>
 
-#include "../fio.h"
+#include "../compiler/compiler.h"
+#include "../oslib/asprintf.h"
+#include "num2str.h"
 
-#define ARRAY_LENGTH(arr)      sizeof(arr) / sizeof((arr)[0])
-
-/*
- * Cheesy number->string conversion, complete with carry rounding error.
+/**
+ * num2str() - Cheesy number->string conversion, complete with carry rounding error.
+ * @num: quantity (e.g., number of blocks, bytes or bits)
+ * @maxlen: max number of digits in the output string (not counting prefix and units, but counting .)
+ * @base: multiplier for num (e.g., if num represents Ki, use 1024)
+ * @pow2: select unit prefix - 0=power-of-10 decimal SI, nonzero=power-of-2 binary IEC
+ * @units: select units - N2S_* constants defined in num2str.h
+ * @returns a malloc'd buffer containing "number[<unit prefix>][<units>]"
  */
-char *num2str(uint64_t num, int maxlen, int base, int pow2, int unit_base)
+char *num2str(uint64_t num, int maxlen, int base, int pow2, enum n2s_unit units)
 {
-       const char *postfix[] = { "", "K", "M", "G", "P", "E" };
-       const char *byte_postfix[] = { "", "B", "bit" };
-       const unsigned int thousand[] = { 1000, 1024 };
-       unsigned int modulo, decimals;
-       int byte_post_index = 0, post_index, carry = 0;
+       const char *sistr[] = { "", "k", "M", "G", "T", "P", "E" };
+       const char *iecstr[] = { "", "Ki", "Mi", "Gi", "Ti", "Pi", "Ei" };
+       const char **unitprefix;
+       static const char *const unitstr[] = {
+               [N2S_NONE]      = "",
+               [N2S_PERSEC]    = "/s",
+               [N2S_BYTE]      = "B",
+               [N2S_BIT]       = "bit",
+               [N2S_BYTEPERSEC]= "B/s",
+               [N2S_BITPERSEC] = "bit/s"
+       };
+       const unsigned int thousand = pow2 ? 1024 : 1000;
+       unsigned int modulo;
+       int post_index, carry = 0;
        char tmp[32];
        char *buf;
 
-       buf = malloc(128);
+       compiletime_assert(sizeof(sistr) == sizeof(iecstr), "unit prefix arrays must be identical sizes");
+       assert(units < FIO_ARRAY_SIZE(unitstr));
+
+       if (pow2)
+               unitprefix = iecstr;
+       else
+               unitprefix = sistr;
 
        for (post_index = 0; base > 1; post_index++)
-               base /= thousand[!!pow2];
+               base /= thousand;
 
-       switch (unit_base) {
-       case 1:
-               byte_post_index = 2;
+       switch (units) {
+       case N2S_NONE:
+               break;
+       case N2S_PERSEC:
+               break;
+       case N2S_BYTE:
+               break;
+       case N2S_BIT:
                num *= 8;
                break;
-       case 8:
-               byte_post_index = 1;
+       case N2S_BYTEPERSEC:
+               break;
+       case N2S_BITPERSEC:
+               num *= 8;
                break;
        }
 
+       /*
+        * Divide by K/Ki until string length of num <= maxlen.
+        */
        modulo = -1U;
-       while (post_index < sizeof(postfix)) {
+       while (post_index < FIO_ARRAY_SIZE(sistr)) {
                sprintf(tmp, "%llu", (unsigned long long) num);
                if (strlen(tmp) <= maxlen)
                        break;
 
-               modulo = num % thousand[!!pow2];
-               num /= thousand[!!pow2];
-               carry = modulo >= thousand[!!pow2] / 2;
+               modulo = num % thousand;
+               num /= thousand;
+               carry = modulo >= thousand / 2;
                post_index++;
        }
 
+       if (post_index >= FIO_ARRAY_SIZE(sistr))
+               post_index = 0;
+
+       /*
+        * If no modulo, then we're done.
+        */
        if (modulo == -1U) {
 done:
-               if (post_index >= ARRAY_LENGTH(postfix))
-                       post_index = 0;
-
-               sprintf(buf, "%llu%s%s", (unsigned long long) num,
-                       postfix[post_index], byte_postfix[byte_post_index]);
+               if (asprintf(&buf, "%llu%s%s", (unsigned long long) num,
+                            unitprefix[post_index], unitstr[units]) < 0)
+                       buf = NULL;
                return buf;
        }
 
+       /*
+        * If no room for decimals, then we're done.
+        */
        sprintf(tmp, "%llu", (unsigned long long) num);
-       decimals = maxlen - strlen(tmp);
-       if (decimals <= 1) {
+       if ((int)(maxlen - strlen(tmp)) <= 1) {
                if (carry)
                        num++;
                goto done;
        }
 
-       do {
-               sprintf(tmp, "%u", modulo);
-               if (strlen(tmp) <= decimals - 1)
-                       break;
+       /*
+        * Fill in everything and return the result.
+        */
+       assert(maxlen - strlen(tmp) - 1 > 0);
+       assert(modulo < thousand);
+       sprintf(tmp, "%.*f", (int)(maxlen - strlen(tmp) - 1),
+               (double)modulo / (double)thousand);
 
-               modulo = (modulo + 9) / 10;
-       } while (1);
+       if (tmp[0] == '1')
+               num++;
 
-       sprintf(buf, "%llu.%u%s%s", (unsigned long long) num, modulo,
-                       postfix[post_index], byte_postfix[byte_post_index]);
+       if (asprintf(&buf, "%llu.%s%s%s", (unsigned long long) num, &tmp[2],
+                    unitprefix[post_index], unitstr[units]) < 0)
+               buf = NULL;
        return buf;
 }