lib.c.svn-base

RT-Thread是发展中的下一代微内核嵌入式实时操作系统

#include "lib.h"
#include "arch.h"

__attribute__ ((weak))
void memset (char* p, char c, rt_uint32 size)
{
    for (;size--;) *(p++)=c;
}

__attribute__ ((weak))
void *memcpy (void* dst, const void* src, rt_uint32 len)
{
    unsigned char* d = (unsigned char*) dst;
    unsigned char* s = (unsigned char*) src;

    while (len-- > 0)*d++ = *s++;

    return dst;                      
}

__attribute__ ((weak))
rt_uint32 strlen(const char *s)
{
    const char *sc;

    for (sc = s; *sc != '\0'; ++sc) ;/* nothing */

    return sc - s;
}

__attribute__ ((weak))
rt_uint32 strncmp(const char* cs, const char* ct, rt_uint32 count)
{
    register signed char __res = 0;

    while (count)
    {
        if ((__res = *cs - *ct++) != 0 || !*cs++)
            break;
        count--;
    }

    return __res;
}

__attribute__ ((weak))
char *strncpy(char *dest, const char *src, rt_uint32 n)
{
	char *a = dest;
	const char *b = src;
	
	/* clean destination */
	memset(dest, 0, n);

	while (n--)
	{
		*a++ = *b;
		if (*b == 0) break;

		b++;
	}

	return dest;
}

/** convert string to long interger */
rt_int32 atol(const char *str)
{
	rt_int32 val = 0;

	while (*str == ' ')	str++;

	while (*str >= '0' && *str <= '9') 
	{
		val *= 10;
		val += (long)(*str - '0');
		str++;
	}

	return val;
}

static void puthexd(rt_uint8 digit)
{
	char table[]="0123456789ABCDEF";
	rt_putc(table[digit]);
}

static void putdec(rt_uint32 byte)
{
	rt_uint8 b1;
	rt_int32 nb;
	int b[30], i = 0;

	while(1)
	{
		b1 = byte%10;
		b[i] = b1;
		nb = byte/10;

		if(nb<=0) break;

		i++;
		byte=nb;
	}

	for(nb = i+1; nb > 0; nb--)
	{
		puthexd(b[nb-1]);
	}
}

static void puthex(rt_uint8 byte)
{
	rt_uint8 lb, rb;

	lb=byte >> 4;
	rb=byte & 0x0F;

	puthexd(lb);
	puthexd(rb);
}

static void puthexi(rt_uint32 dword)
{
	puthex( (dword & 0xFF000000) >>24);
	puthex( (dword & 0x00FF0000) >>16);
	puthex( (dword & 0x0000FF00) >>8);
	puthex( (dword & 0x000000FF));
}

static void vprintf(const char *fmt, va_list args)
{
	while (*fmt)
	{
		switch (*fmt)
		{
		case '%':
			fmt++;

			switch (*fmt)
			{
			case 's':
				rt_puts(va_arg(args, char *));
			break;

			case 'c':
				rt_putc(va_arg(args, unsigned int));
			break;

			case 'i':
				putdec(va_arg(args, unsigned int));
			break;

			case 'x':
				puthex(va_arg(args, unsigned int));
			break;

			case 'X':
				puthexi(va_arg(args, unsigned int));
			break;
			}

			break;

		default:
			rt_putc(*fmt);
			break;
		}

		fmt++;
	}
}

void printf(const char *fmt, ...)
{
  va_list args;
  va_start(args, fmt);

  vprintf(fmt, args);

  va_end(args);
}