source: mainline/src/debug/print.c@ 6ef72c9

/*
 * Copyright (C) 2001-2004 Jakub Jermar
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * - Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 * - The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include <putchar.h>
#include <print.h>
#include <synch/spinlock.h>
#include <arch/arg.h>


static char digits[] = "0123456789abcdef";
static spinlock_t printflock;

void print_str(char *str)
{
        int i = 0;
        char c;
    
        while (c = str[i++])
            putchar(c);
}


/* 
 * This is a universal function for printing hexadecimal numbers of fixed
 * width.
 */
void print_fixed_hex(__native num, int width)
{
        int i;
    
        for (i = width*8 - 4; i >= 0; i -= 4)
            putchar(digits[(num>>i) & 0xf]);
}

/* 
 * This is a universal function for printing decimal and hexadecimal numbers.
 * It prints only significant digits.
 */
void print_number(__native num, int base)
{ 
        char d[sizeof(__native)*8+1];           /* this is good enough even for base == 2 */
        int i = sizeof(__native)*8-1;
    
        do {
                d[i--] = digits[num % base];
        } while (num /= base);
        
        d[sizeof(__native)*8] = 0;      
        print_str(&d[i + 1]);
}

/*
 * This is our function for printing formatted text.
 * It's much simpler than the user-space one.
 * We are greateful for this function.
 */
void printf(char *fmt, ...)
{
        int irqpri, i = 0;
        va_list ap;
        char c; 

        va_start(ap, fmt);

        irqpri = cpu_priority_high();
        spinlock_lock(&printflock);

        while (c = fmt[i++]) {
                switch (c) {

                    /* control character */
                    case '%':
                            switch (c = fmt[i++]) {

                                /* percentile itself */
                                case '%':
                                        break;

                                /*
                                 * String and character conversions.
                                 */
                                case 's':
                                        print_str(va_arg(ap, char_ptr));
                                        goto loop;

                                case 'c':
                                        c = (char) va_arg(ap, int);
                                        break;

                                /*
                                 * Hexadecimal conversions with fixed width.
                                 */
                                case 'L': 
                                        print_str("0x");
                                case 'l':
                                        print_fixed_hex(va_arg(ap, __native), INT32);
                                        goto loop;

                                case 'W':
                                        print_str("0x");
                                case 'w':
                                        print_fixed_hex(va_arg(ap, __native), INT16);
                                        goto loop;

                                case 'B':
                                        print_str("0x");
                                case 'b':
                                        print_fixed_hex(va_arg(ap, __native), INT8);
                                        goto loop;

                                /*
                                 * Decimal and hexadecimal conversions.
                                 */
                                case 'd':
                                        print_number(va_arg(ap, __native), 10);
                                        goto loop;

                                case 'X':
                                        print_str("0x");
                                case 'x':
                                        print_number(va_arg(ap, __native), 16);
                                        goto loop;
            
                                /*
                                 * Bad formatting.
                                 */
                                default:
                                        goto out;
                            }

                    default: putchar(c);
                }
        
loop:
                ;
        }

out:
        spinlock_unlock(&printflock);
        cpu_priority_restore(irqpri);
        
        va_end(ap);
}