kern

diff src/klibc/stdlib.c @ 6:7e40f14617ed

forgot to add stdarg.h and stdlib.c
author John Tsiombikas <nuclear@member.fsf.org>
date Thu, 13 Jan 2011 20:24:10 +0200
parents
children f83f50c17c3b
line diff
     1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/src/klibc/stdlib.c	Thu Jan 13 20:24:10 2011 +0200
     1.3 @@ -0,0 +1,86 @@
     1.4 +#include <stdlib.h>
     1.5 +#include <ctype.h>
     1.6 +
     1.7 +int atoi(const char *str)
     1.8 +{
     1.9 +	return atol(str);
    1.10 +}
    1.11 +
    1.12 +long atol(const char *str)
    1.13 +{
    1.14 +	long acc = 0;
    1.15 +	int sign = 1;
    1.16 +
    1.17 +	while(isspace(*str)) str++;
    1.18 +
    1.19 +	if(*str == '+') {
    1.20 +		str++;
    1.21 +	} else if(*str == '-') {
    1.22 +		sign = -1;
    1.23 +		str++;
    1.24 +	}
    1.25 +
    1.26 +	while(*str && isdigit(*str)) {
    1.27 +		acc = acc * 10 + (*str - '0');
    1.28 +		str++;
    1.29 +	}
    1.30 +
    1.31 +	return sign > 0 ? acc : -acc;
    1.32 +}
    1.33 +
    1.34 +void itoa(int val, char *buf, int base)
    1.35 +{
    1.36 +	static char rbuf[16];
    1.37 +	char *ptr = rbuf;
    1.38 +	int neg = 0;
    1.39 +
    1.40 +	if(val < 0) {
    1.41 +		neg = 1;
    1.42 +		val = -val;
    1.43 +	}
    1.44 +
    1.45 +	if(val == 0) {
    1.46 +		*ptr++ = '0';
    1.47 +	}
    1.48 +
    1.49 +	while(val) {
    1.50 +		int digit = val % base;
    1.51 +		*ptr++ = digit < 10 ? (digit + '0') : (digit - 10 + 'a');
    1.52 +		val /= base;
    1.53 +	}
    1.54 +
    1.55 +	if(neg) {
    1.56 +		*ptr++ = '-';
    1.57 +	}
    1.58 +
    1.59 +	ptr--;
    1.60 +
    1.61 +	while(ptr >= rbuf) {
    1.62 +		*buf++ = *ptr--;
    1.63 +	}
    1.64 +	*buf = 0;
    1.65 +}
    1.66 +
    1.67 +void utoa(unsigned int val, char *buf, int base)
    1.68 +{
    1.69 +	static char rbuf[16];
    1.70 +	char *ptr = rbuf;
    1.71 +
    1.72 +	if(val == 0) {
    1.73 +		*ptr++ = '0';
    1.74 +	}
    1.75 +
    1.76 +	while(val) {
    1.77 +		unsigned int digit = val % base;
    1.78 +		*ptr++ = digit < 10 ? (digit + '0') : (digit - 10 + 'a');
    1.79 +		val /= base;
    1.80 +	}
    1.81 +
    1.82 +	ptr--;
    1.83 +
    1.84 +	while(ptr >= rbuf) {
    1.85 +		*buf++ = *ptr--;
    1.86 +	}
    1.87 +	*buf = 0;
    1.88 +}
    1.89 +