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#include <printf.h>
#include <stdint.h>
#include <sbi.h>
#include <stdarg.h>

static char digits[] = "0123456789abcdef";

int
puts(const char *str)
{
	do {
		sbi_console_putchar(*str);
	} while (*(str++) != '\0');
}

#define PUTCHAR(c)      sbi_console_putchar(c)

static void
printint(int xx, int base, int sign)
{
        char buf[16];
        int i;
        unsigned int x;

        if (sign && (sign = xx < 0))
                x = -xx;
        else 
                x = xx; 

        i = 0;
        do {
                buf[i++] = digits[x % base];
        } while ((x /= base) != 0);

        if (sign)
                buf[i++] = '-';
        while (--i >= 0)
                PUTCHAR(buf[i]);

}

static void 
printptr(uint64_t x)
{
        int i;
        puts("0x");
        for (i = 0; i < (sizeof(uint64_t) * 2); i++, x <<= 4)
                PUTCHAR(digits[x >> (sizeof(int64_t) * 8 - 4)]);
}

void
printf(const char *fmt, ...) 
{
        va_list ap;
        int i, c;
        char *s;

        va_start(ap, fmt);

        for (i = 0; (c = fmt[i] & 0xff) != 0; i++) {
                if (c != '%') {
                        PUTCHAR(c);
                        continue;
                }
                c = fmt[++i] & 0xff;
                if (!c) 
                        break;

                switch (c) {
                        case 'd':
                        case 'i':
                                printint(va_arg(ap, int), 10, 1);
                                break;
                        case 'x':
                                printint(va_arg(ap, int), 16, 1);
                                break;
                        case 'p':
                                printptr(va_arg(ap, uint64_t));
                                break;
                        case '%':
                                PUTCHAR('%');
                                break;
                }
        }
}