mirror of
https://gitlab.nic.cz/labs/bird.git
synced 2024-12-23 18:21:54 +00:00
2915e711f7
The glibc's generic parser is slow due to its versatility. Specialized parsers for base-10 and base-16 are much faster and we don't use other bases.
62 lines
1.1 KiB
C
62 lines
1.1 KiB
C
/*
|
|
* BIRD Library -- Parse numbers
|
|
*
|
|
* (c) 2019 Maria Matejka <mq@jmq.cz>
|
|
*
|
|
* Can be freely distributed and used under the terms of the GNU GPL.
|
|
*/
|
|
|
|
#include "nest/bird.h"
|
|
#include "lib/string.h"
|
|
|
|
#include <errno.h>
|
|
|
|
#define ULI_MAX_DIV10 (UINT64_MAX / 10)
|
|
#define ULI_MAX_MOD10 (UINT64_MAX % 10)
|
|
|
|
u64
|
|
bstrtoul10(const char *str, char **end)
|
|
{
|
|
u64 out = 0;
|
|
for (*end = (char *) str; (**end >= '0') && (**end <= '9'); (*end)++) {
|
|
u64 digit = **end - '0';
|
|
if ((out > ULI_MAX_DIV10) ||
|
|
(out == ULI_MAX_DIV10) && (digit > ULI_MAX_MOD10)) {
|
|
errno = ERANGE;
|
|
return UINT64_MAX;
|
|
}
|
|
|
|
out *= 10;
|
|
out += (**end) - '0';
|
|
}
|
|
return out;
|
|
}
|
|
|
|
u64
|
|
bstrtoul16(const char *str, char **end)
|
|
{
|
|
u64 out = 0;
|
|
for (int i=0; i<=(64/4); i++) {
|
|
switch (str[i]) {
|
|
case '0' ... '9':
|
|
out *= 16;
|
|
out += str[i] - '0';
|
|
break;
|
|
case 'a' ... 'f':
|
|
out *= 16;
|
|
out += str[i] + 10 - 'a';
|
|
break;
|
|
case 'A' ... 'F':
|
|
out *= 16;
|
|
out += str[i] + 10 - 'A';
|
|
break;
|
|
default:
|
|
*end = (char *) &(str[i]);
|
|
return out;
|
|
}
|
|
}
|
|
|
|
errno = ERANGE;
|
|
return UINT64_MAX;
|
|
}
|