omos-tcnj2024/sys/lib.c

171 lines
2.8 KiB
C

#include <types.h>
static char strbuf[32];
u32
strlen(const char *str)
{
size_t i;
for (i = 0; str[i] != NULL; i++);
return i;
}
char*
strtol(s32 num, char *str, s32 base)
{
s32 i = 0;
if (num < 0 && base == 10) {
str[i++] = '-';
num = -num;
}
while (num != 0) {
s32 remainder = num % base;
str[i++] = (remainder < 10) ? remainder + '0' : remainder + 'a' - 10;
num/=base;
}
str[i] = '\0';
return str;
}
char*
strtoul(u32 num, char *str, s32 base)
{
s32 i = 0;
while (num != 0) {
s32 remainder = num % base;
str[i++] = (remainder < 10) ? remainder + '0' : remainder + 'a' - 10;
num/=base;
}
str[i] = '\0';
return str;
}
char*
strcpy(char *dest, const char *src)
{
u32 i = 0;
while (src[i] != NULL) {
dest[i] = src[i];
i++;
}
return dest;
}
char*
strncpy(char *dest, const char *src, size_t count)
{
u32 i = 0;
while (src[i] != NULL && i < count) {
dest[i] = src[i];
i++;
}
return dest;
}
char*
strcat(char *dest, const char *src)
{
u32 i = 0;
while (dest[i] != NULL) i++;
while (src[i] != NULL) {
dest[i] = src[i];
i++;
}
dest[i] = '\0';
return dest;
}
char*
strncat(char *dest, const char *src, size_t count)
{
u32 i = 0;
while (dest[i] != NULL) i++;
while (src[i] != NULL && i < count) {
dest[i] = src[i];
i++;
}
dest[i] = '\0';
return dest;
}
s32
strcmp(const char *lhs, const char *rhs)
{
u32 i = 0;
while (lhs[i] != NULL && rhs[i] != NULL) {
if (lhs[i] != rhs[i]) {
return lhs[i] - rhs[i];
}
}
return 0;
}
s32
printf(const char *format, ...)
{
const u32 len = sizeof(format);
va_list list;
va_start(list, len);
for (u32 i = 0; i < len; i++) {
if (format[i] == '%') {
if (format[i + 1] == 'd' || format[i + 1] == 'i') {
//integer numbers
const s32 num = va_arg(list, s32);
const char* str = strtol(num, strbuf, 10);
vga_write(str, sizeof(str), 0x0f);
} else if (format[i + 1] == 'o') {
//octal numbers
const s32 num = va_arg(list, s32);
const char *str = strtol(num, strbuf, 8);
vga_write(str, sizeof(str), 0x0f);
} else if (format[i + 1] == 'u') {
//unsigned integers
const u32 num = va_arg(list, u32);
const char *str = strtoul(num, strbuf, 10);
vga_write(str, sizeof(str), 0x0f);
} else if (format[i + 1] == 'x') {
//hexadecimal numbers
const u32 num = va_arg(list, u32);
const char* str = strtoul(num, strbuf, 16);
vga_write(str, sizeof(str), 0x0f);
} else if (format[i + 1] == 's') {
//strings
const char *str = va_arg(list, char*);
vga_write(str, strlen(str), 0x0f);
} else if (format[i + 1] == 'c') {
//one character
vga_write(va_arg(list, char), 1, 0x0f);
} else if (format[i + 1] == '%') {
vga_write('%', 1, 0x0f);
}
} else if (format[i] == '\\' && format[i + 1] == '%') {
vga_write('%', 1, 0x0f);
} else {
vga_write(format[i], 1, 0x0f);
}
}
}