X-Git-Url: https://git.kernel.dk/?a=blobdiff_plain;f=lib%2Fnum2str.c;h=40fb3aec923d3ce6199b64d0cf4c791c92e2151a;hb=b4f5e72f1383;hp=e114cdf8ebea83db1d79725403475f977b7d7cc9;hpb=1ec3d69b0ed8cc7a3eba0192685034d5442989e4;p=fio.git

diff --git a/lib/num2str.c b/lib/num2str.c
index e114cdf8..40fb3aec 100644
--- a/lib/num2str.c
+++ b/lib/num2str.c
@@ -1,48 +1,120 @@
+#include <assert.h>
 #include <stdlib.h>
 #include <stdio.h>
 #include <string.h>
 
-/*
- * Cheesy number->string conversion, complete with carry rounding error.
+#include "../compiler/compiler.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, 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(unsigned long num, int maxlen, int base, int pow2)
+char *num2str(uint64_t num, int maxlen, int base, int pow2, enum n2s_unit units)
 {
-	char postfix[] = { ' ', 'K', 'M', 'G', 'P', 'E' };
-	unsigned int thousand[] = { 1000, 1024 };
-	unsigned int modulo, decimals;
-	int post_index;
-	char tmp[32], fmt[8];
+	const char *sistr[] = { "", "k", "M", "G", "T", "P" };
+	const char *iecstr[] = { "", "Ki", "Mi", "Gi", "Ti", "Pi" };
+	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[] = { 1000, 1024 };
+	unsigned int modulo;
+	int post_index, carry = 0;
+	char tmp[32], fmt[32];
 	char *buf;
 
+	compiletime_assert(sizeof(sistr) == sizeof(iecstr), "unit prefix arrays must be identical sizes");
+	assert(units < ARRAY_SIZE(unitstr));
+
 	buf = malloc(128);
+	if (!buf)
+		return NULL;
+
+	if (pow2)
+		unitprefix = iecstr;
+	else
+		unitprefix = sistr;
 
 	for (post_index = 0; base > 1; post_index++)
 		base /= thousand[!!pow2];
 
+	switch (units) {
+	case N2S_NONE:
+		break;
+	case N2S_PERSEC:
+		break;
+	case N2S_BYTE:
+		break;
+	case N2S_BIT:
+		num *= 8;
+		break;
+	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)) {
-		sprintf(tmp, "%lu", num);
+	while (post_index < sizeof(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;
 		post_index++;
 	}
 
+	/*
+	 * If no modulo, then we're done.
+	 */
 	if (modulo == -1U) {
 done:
-		sprintf(buf, "%lu%c", num, postfix[post_index]);
+		if (post_index >= ARRAY_SIZE(sistr))
+			post_index = 0;
+
+		sprintf(buf, "%llu%s%s", (unsigned long long) num,
+			unitprefix[post_index], unitstr[units]);
 		return buf;
 	}
 
-	sprintf(tmp, "%lu", num);
-	decimals = maxlen - strlen(tmp);
-	if (decimals <= 1)
+	/*
+	 * If no room for decimals, then we're done.
+	 */
+	sprintf(tmp, "%llu", (unsigned long long) num);
+	if ((int)(maxlen - strlen(tmp)) <= 1) {
+		if (carry)
+			num++;
 		goto done;
+	}
+
+	/*
+	 * Fill in everything and return the result.
+	 */
+	assert(maxlen - strlen(tmp) - 1 > 0);
+	assert(modulo < thousand[!!pow2]);
+	sprintf(fmt, "%%.%df", (int)(maxlen - strlen(tmp) - 1));
+	sprintf(tmp, fmt, (double)modulo / (double)thousand[!!pow2]);
 
-	sprintf(fmt, "%%.%uu", decimals - 1);
-	sprintf(tmp, fmt, modulo);
-	sprintf(buf, "%lu.%s%c", num, tmp, postfix[post_index]);
+	sprintf(buf, "%llu.%s%s%s", (unsigned long long) num, &tmp[2],
+			unitprefix[post_index], unitstr[units]);
 	return buf;
 }