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 448d3ff88b00cbe41c3fcbeb21665d19496cf2f7..cd89a0e59171291017ece4429bc70b4e43eb95ca 100644 (file)
--- a/lib/num2str.c
+++ b/lib/num2str.c
@@ -1,38 +1,42 @@
+#include <assert.h>
 #include <stdlib.h>
 #include <stdio.h>
 #include <string.h>
 
 #include "../compiler/compiler.h"
+#include "../oslib/asprintf.h"
 #include "num2str.h"
 
-#define ARRAY_SIZE(x)    (sizeof((x)) / (sizeof((x)[0])))
-
 /**
  * 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)
+ * @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_* macros defined in num2str.h
+ * @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 units)
+char *num2str(uint64_t num, int maxlen, int base, int pow2, enum n2s_unit units)
 {
-       const char *sistr[] = { "", "k", "M", "G", "T", "P" };
-       const char *iecstr[] = { "", "Ki", "Mi", "Gi", "Ti", "Pi" };
+       const char *sistr[] = { "", "k", "M", "G", "T", "P", "E" };
+       const char *iecstr[] = { "", "Ki", "Mi", "Gi", "Ti", "Pi", "Ei" };
        const char **unitprefix;
-       const char *unitstr[] = { "", "/s", "B", "bit", "B/s", "bit/s" };
-       const unsigned int thousand[] = { 1000, 1024 };
-       unsigned int modulo, decimals;
-       int unit_index = 0, post_index, carry = 0;
+       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;
 
        compiletime_assert(sizeof(sistr) == sizeof(iecstr), "unit prefix arrays must be identical sizes");
-
-       buf = malloc(128);
-       if (!buf)
-               return NULL;
+       assert(units < FIO_ARRAY_SIZE(unitstr));
 
        if (pow2)
                unitprefix = iecstr;
@@ -40,67 +44,77 @@ char *num2str(uint64_t num, int maxlen, int base, int pow2, int units)
                unitprefix = sistr;
 
        for (post_index = 0; base > 1; post_index++)
-               base /= thousand[!!pow2];
+               base /= thousand;
 
        switch (units) {
+       case N2S_NONE:
+               break;
        case N2S_PERSEC:
-               unit_index = 1;
                break;
        case N2S_BYTE:
-               unit_index = 2;
                break;
        case N2S_BIT:
-               unit_index = 3;
                num *= 8;
                break;
        case N2S_BYTEPERSEC:
-               unit_index = 4;
                break;
        case N2S_BITPERSEC:
-               unit_index = 5;
                num *= 8;
                break;
        }
 
+       /*
+        * Divide by K/Ki until string length of num <= maxlen.
+        */
        modulo = -1U;
-       while (post_index < sizeof(sistr)) {
+       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_SIZE(sistr))
-                       post_index = 0;
-
-               sprintf(buf, "%llu%s%s", (unsigned long long) num,
-                       unitprefix[post_index], unitstr[unit_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 ((int)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,
-                       unitprefix[post_index], unitstr[unit_index]);
+       if (asprintf(&buf, "%llu.%s%s%s", (unsigned long long) num, &tmp[2],
+                    unitprefix[post_index], unitstr[units]) < 0)
+               buf = NULL;
        return buf;
 }