rulimine/stage2/lib/libc.c
2020-09-16 17:22:05 +02:00

70 lines
1.2 KiB
C

#include <stddef.h>
#include <stdint.h>
#include <lib/libc.h>
int toupper(int c) {
if (c >= 'a' && c <= 'z') {
return c - 0x20;
}
return c;
}
int tolower(int c) {
if (c >= 'A' && c <= 'Z') {
return c + 0x20;
}
return c;
}
char *strcpy(char *dest, const char *src) {
size_t i;
for (i = 0; src[i]; i++)
dest[i] = src[i];
dest[i] = 0;
return dest;
}
char *strncpy(char *dest, const char *src, size_t n) {
size_t i;
for (i = 0; i < n && src[i]; i++)
dest[i] = src[i];
for ( ; i < n; i++)
dest[i] = 0;
return dest;
}
int strcmp(const char *s1, const char *s2) {
for (size_t i = 0; ; i++) {
char c1 = s1[i], c2 = s2[i];
if (c1 != c2)
return c1 < c2 ? -1 : 1;
if (!c1)
return 0;
}
}
int strncmp(const char *s1, const char *s2, size_t n) {
for (size_t i = 0; i < n; i++) {
char c1 = s1[i], c2 = s2[i];
if (c1 != c2)
return c1 < c2 ? -1 : 1;
if (!c1)
return 0;
}
return 0;
}
size_t strlen(const char *str) {
size_t len;
for (len = 0; str[len]; len++);
return len;
}