projekty/Source/example1/src/printf.c

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/*
        Copyright 2001, 2002 Georges Menie (www.menie.org)

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU Lesser General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
*/

/*
        putchar is the only external dependency for this file,
        if you have a working putchar, just remove the following
        define. If the function should be called something else,
        replace outbyte(c) by your own function call.
*/
#include "printf.h"

void outbyte(int c)
{
        UARTWriteChar(c);
}
#define putchar(c) outbyte(c)

void printchar(char **str, int c)
{
//      extern int putchar(int c);
        if (str) {
                **str = c;
                ++(*str);
                WD_Reset();
        }
        else (void)putchar(c);
}

#define PAD_RIGHT 1
#define PAD_ZERO 2

int prints(char **out, const char *string, int width, int pad)
{
        register int pc = 0, padchar = ' ';

        if (width > 0) {
                register int len = 0;
                register const char *ptr;
                for (ptr = string; *ptr; ++ptr) ++len;
                if (len >= width) width = 0;
                else width -= len;
                if (pad & PAD_ZERO) padchar = '0';
        }
        if (!(pad & PAD_RIGHT)) {
                for ( ; width > 0; --width) {
                        printchar (out, padchar);
                        ++pc;
                }
        }
        for ( ; *string ; ++string) {
                printchar (out, *string);
                ++pc;
        }
        for ( ; width > 0; --width) {
                printchar (out, padchar);
                ++pc;
        }

        return pc;
}

/* the following should be enough for 32 bit int */
#define PRINT_BUF_LEN 12

int printi(char **out, int i, int b, int sg, int width, int pad, int letbase)
{
        char print_buf[PRINT_BUF_LEN];
        register char *s;
        register int t, neg = 0, pc = 0;
        register unsigned int u = i;

        if (i == 0) {
                print_buf[0] = '0';
                print_buf[1] = '\0';
                return prints (out, print_buf, width, pad);
        }

        if (sg && b == 10 && i < 0) {
                neg = 1;
                u = -i;
        }

        s = print_buf + PRINT_BUF_LEN-1;
        *s = '\0';

        while (u) {
                t = u % b;
                if( t >= 10 )
                        t += letbase - '0' - 10;
                *--s = t + '0';
                u /= b;
        }

        if (neg) {
                if( width && (pad & PAD_ZERO) ) {
                        printchar (out, '-');
                        ++pc;
                        --width;
                }
                else {
                        *--s = '-';
                }
        }

        return pc + prints (out, s, width, pad);
}

int print(char **out, int *varg)
{
        register int width, pad;
        register int pc = 0;
        register char *format = (char *)(*varg++);
        char scr[2];

        for (; *format != 0; ++format) {
        #if 1
                WD_Reset();
        #endif
                if (*format == '%') {
                        ++format;
                        width = pad = 0;
                        if (*format == '\0') break;
                        if (*format == '%') goto out;
                        if (*format == '-') {
                                ++format;
                                pad = PAD_RIGHT;
                        }
                        while (*format == '0') {
                                ++format;
                                pad |= PAD_ZERO;
                        }
                        for ( ; *format >= '0' && *format <= '9'; ++format) {
                                width *= 10;
                                width += *format - '0';
                        }
                        if( *format == 's' ) {
                                register char *s = *((char **)varg++);
                                pc += prints (out, s?s:"(null)", width, pad);
                                continue;
                        }
                        if( *format == 'd' ) {
                                pc += printi (out, *varg++, 10, 1, width, pad, 'a');
                                continue;
                        }
                        if( *format == 'x' ) {
                                pc += printi (out, *varg++, 16, 0, width, pad, 'a');
                                continue;
                        }
                        if( *format == 'X' ) {
                                pc += printi (out, *varg++, 16, 0, width, pad, 'A');
                                continue;
                        }
                        if( *format == 'u' ) {
                                pc += printi (out, *varg++, 10, 0, width, pad, 'a');
                                continue;
                        }
                        if( *format == 'c' ) {
                                /* char are converted to int then pushed on the stack */
                                scr[0] = *varg++;
                                scr[1] = '\0';
                                pc += prints (out, scr, width, pad);
                                continue;
                        }
                }
                else {
                out:
                        printchar (out, *format);
                        ++pc;
                }
        }
        if (out) **out = '\0';
        WD_Reset();
        return pc;
}

/* assuming sizeof(void *) == sizeof(int) */

int printf(const char *format, ...)
{
        register int *varg = (int *)(&format);
        return print(0, varg);
}

int sprintf(char *out, const char *format, ...)
{
        register int *varg = (int *)(&format);
        return print(&out, varg);
}

/* if you compile this file with
 *   gcc -Wall $(YOUR_C_OPTIONS) -DTEST_PRINTF -c printf.c
 * you will get a normal warning:
 *   printf.c:214: warning: spurious trailing `%' in format
 * this line is testing an invalid % at the end of the format string.
 *
 * this should display (on 32bit int machine) :
 *
 * Hello world!
 * printf test
 * (null) is null pointer
 * 5 = 5
 * -2147483647 = - max int
 * char a = 'a'
 * hex ff = ff
 * hex 00 = 00
 * signed -3 = unsigned 4294967293 = hex fffffffd
 * 0 message(s)
 * 0 message(s) with %
 * justif: "left      "
 * justif: "     right"
 *  3: 0003 zero padded
 *  3: 3    left justif.
 *  3:    3 right justif.
 * -3: -003 zero padded
 * -3: -3   left justif.
 * -3:   -3 right justif.
 */

//#endif

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