Files
my-kern/kernel/libc/string.c
Rick Rongen 77c8dca72a feat: implemented errno, strtol. Started ustar. Reformatted headers and
code. Added some self-tests. Started prepwork for vfs.
2021-03-14 21:14:22 +01:00

74 lines
1.4 KiB
C

//
// Created by rick on 01-02-21.
//
#include <string.h>
#include <sys/param.h>
int memcpy(void *dst, const void *src, size_t amount) {
for (size_t i = 0; i < amount; i++) {
((char *) dst)[i] = ((const char *) src)[i];
}
return 0;
}
int memset(void *dst, int data, size_t amount) {
for (size_t i = 0; i < amount; ++i) {
((char *) dst)[i] = (char) data;
}
return 0;
}
int strcpy(char *dst, const char *src) {
return memcpy(dst, src, strlen(src) + 1);
}
size_t strlen(const char *str) {
int length = 0;
while (str[length] != 0) {
length++;
}
return length;
}
int strcmp(const char *s1, const char *s2) {
int len1 = strlen(s1);
int len2 = strlen(s2);
return strncmp(s1, s2, MAX(len1, len2));
}
const char *strchr(const char *s, char c) {
int index = 0;
while (1) {
if (s[index] == c) {
return &s[index];
}
if (s[index] == 0) {
return NULL;
}
index++;
}
}
int strncmp(const char *s1, const char *s2, int n) {
for (int i = 0; i < n; ++i) {
if (s1[i] == 0 && s2[i] == 0) {
return 0;
}
if (s1[i] == 0) {
return -1;
}
if (s2[i] == 0) {
return 1;
}
if (s1[i] > s2[i]) {
return -1;
}
if (s1[i] < s2[i]) {
return 1;
}
}
return 0;
}