root/library/printf.c

DEFINITIONS

1. printf

#include "syscalls.h"
#include <stdarg.h>

int printf(unsigned char *s, ...)
{
    va_list ap;
    va_start(ap, s);

    unsigned char sprocessed[256];
    int i = 0;
    int j = 0;
    int k = 0;
    while (s[i]) {
        if (s[i] != '%') {
            sprocessed[j] = s[i];
            i++;
            j++;
        } else {
            i++;
            switch (s[i]) {
            case 'c':
                ;
                int c = va_arg(ap, int);
                sprocessed[j++] = c;
                break;
            case 's':
                ;
                unsigned char *s1 = va_arg(ap, unsigned char *);
                while (s1[k])
                    sprocessed[j++] = s1[k++];
                break;
            case 'd':
                ;
                char buffer[8];
                int number = va_arg(ap, int);
                intToAsc(number, buffer, 8);
                for (k = 0; k < 8; k++)
                    if (buffer[k] != ' ')
                        sprocessed[j++] = buffer[k];
                break;
            case 'x':
                ;
                number = va_arg(ap, int);
                intToHAsc(number, buffer, 8);
                sprocessed[j++] = '0';
                sprocessed[j++] = 'x';
                for (k = 0; k < 8; k++)
                    sprocessed[j++] = buffer[k];
                break;
            default:
                break;
            }
            i++;
        }
    }
    va_end(ap);
    write(STDOUT, sprocessed, j);
    return 0;
}