bootloader/lib.c at main · nkraetzschmar/bootloader · GitHub

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#include "types.h"
#include "lib.h"
#include "bios_services.h"
#include "gpt.h"

void flush()
{
	print_char(0x00);
}

void print_str(const char *str)
{
	for (const char *ptr = str; *ptr; ++ptr) print_char(*ptr);
}

uint8 memeq(const void *a, const void *b, uint16 len)
{
	for (uint16 i = 0; i < len; ++i) if (((uint8 *) a)[i] != ((uint8 *) b)[i]) return 0;
	return 1;
}

void memcpy(void *dst, const void *src, uint16 len)
{
	for (uint16 i = 0; i < len; ++i) ((uint8 *) dst)[i] = ((uint8 *) src)[i];
}

static char lowercase(char c)
{
	if (c >= 'A' && c <= 'Z') return 'a' + (c - 'A');
	else return c;
}

uint16 strlen(const char *str)
{
	uint16 len;

	len = 0;

	while (*str) {
		++len;
		++str;
	}

	return len;
}

uint8 streq(const char *a, const char *b)
{
	while (1) {
		if (lowercase(*a) != lowercase(*b)) return 0;
		if (*a == 0x00) break;
		++a;
		++b;
	}

	return 1;
}

void strcpy(char *dst, const char *src, uint16 len)
{
	uint16 i;

	for (i = 0; i < len - 1 && src[i] != 0x00; ++i) dst[i] = src[i];
	for (; i < len; ++i) dst[i] = 0x00;
}

static const char *hex_map = "0123456789ABCDEF";

static void print_hex(const uint8 *buf, uint16 len, int8 step)
{
	uint8 value;
	uint8 low_bits;
	uint8 high_bits;

	for (int16 i = 0; i < len; ++i) {
		value = *(buf + (i * step));
		low_bits  = value & 0x0f;
		high_bits = (value >> 4) & 0x0f;

		print_char(hex_map[high_bits]);
		print_char(hex_map[low_bits]);
	}
}

void print_hex_be(const uint8 *buf, uint16 len)
{
	print_hex(buf, len, 1);
}

void print_hex_le(const uint8 *buf, uint16 len)
{
	print_hex(buf + len - 1, len, -1);
}