perf tools: Add new perf_atoll() function to parse string representing size in bytes

This patch modifies util/string.[ch] to add new function:
perf_atoll() to parse string representing size in bytes.

This function parses (\d+)(b|B|kb|KB|mb|MB|gb|GB) (e.g. "256MB")
and returns its numeric value. (e.g. 268435456)

Signed-off-by: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <1258285013-4759-1-git-send-email-mitake@dcl.info.waseda.ac.jp>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Hitoshi Mitake 2009-11-15 20:36:53 +09:00 committed by Ingo Molnar
parent 0ffa798d94
commit d2fb8b4151
2 changed files with 85 additions and 0 deletions

View file

@ -1,5 +1,7 @@
#include <string.h>
#include <stdlib.h>
#include "string.h"
#include "util.h"
static int hex(char ch)
{
@ -43,3 +45,85 @@ char *strxfrchar(char *s, char from, char to)
return s;
}
#define K 1024LL
/*
* perf_atoll()
* Parse (\d+)(b|B|kb|KB|mb|MB|gb|GB|tb|TB) (e.g. "256MB")
* and return its numeric value
*/
s64 perf_atoll(const char *str)
{
unsigned int i;
s64 length = -1, unit = 1;
if (!isdigit(str[0]))
goto out_err;
for (i = 1; i < strlen(str); i++) {
switch (str[i]) {
case 'B':
case 'b':
break;
case 'K':
if (str[i + 1] != 'B')
goto out_err;
else
goto kilo;
case 'k':
if (str[i + 1] != 'b')
goto out_err;
kilo:
unit = K;
break;
case 'M':
if (str[i + 1] != 'B')
goto out_err;
else
goto mega;
case 'm':
if (str[i + 1] != 'b')
goto out_err;
mega:
unit = K * K;
break;
case 'G':
if (str[i + 1] != 'B')
goto out_err;
else
goto giga;
case 'g':
if (str[i + 1] != 'b')
goto out_err;
giga:
unit = K * K * K;
break;
case 'T':
if (str[i + 1] != 'B')
goto out_err;
else
goto tera;
case 't':
if (str[i + 1] != 'b')
goto out_err;
tera:
unit = K * K * K * K;
break;
case '\0': /* only specified figures */
unit = 1;
break;
default:
if (!isdigit(str[i]))
goto out_err;
break;
}
}
length = atoll(str) * unit;
goto out;
out_err:
length = -1;
out:
return length;
}

View file

@ -5,6 +5,7 @@
int hex2u64(const char *ptr, u64 *val);
char *strxfrchar(char *s, char from, char to);
s64 perf_atoll(const char *str);
#define _STR(x) #x
#define STR(x) _STR(x)