busybox/libbb/kernel_version.c
Denys Vlasenko 2496616b0a avoid using strok - eliminates use of hidden global variable
function                                             old     new   delta
udhcp_str2optset                                     616     650     +34
setpriv_main                                         950     975     +25
switch_root_main                                     688     706     +18
parse                                                958     970     +12
getopt_main                                          622     628      +6
parse_resolvconf                                     302     306      +4
mpstat_main                                         1139    1142      +3
static.p                                               4       -      -4
cdcmd                                                717     702     -15
strtok                                               148       -    -148
------------------------------------------------------------------------------
(add/remove: 0/3 grow/shrink: 7/1 up/down: 102/-167)          Total: -65 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2020-10-06 02:36:47 +02:00

36 lines
830 B
C

/* vi: set sw=4 ts=4: */
/*
* Utility routines.
*
* Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
*
* Licensed under GPLv2 or later, see file LICENSE in this source tree.
*/
#include "libbb.h"
/* After libbb.h, since it needs sys/types.h on some systems */
#include <sys/utsname.h> /* for uname(2) */
/* Returns current kernel version encoded as major*65536 + minor*256 + patch,
* so, for example, to check if the kernel is greater than 2.2.11:
*
* if (get_linux_version_code() > KERNEL_VERSION(2,2,11)) { <stuff> }
*/
int FAST_FUNC get_linux_version_code(void)
{
struct utsname name;
char *t;
int r;
uname(&name); /* never fails */
t = name.release - 1;
r = 1;
do {
r <<= 8;
if (t) {
r += atoi(++t);
t = strchr(t, '.');
}
} while (r < 0x1000000);
return r - 0x1000000;
}