/*	Copyright 2001, 2002 Georges Menie (www.menie.org)	stdarg version contributed by Christian Ettinger    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, leave it commented out.	If not, uncomment the define below and	replace outbyte(c) by your own function call.#define putchar(c) outbyte(c)*/#include <stdarg.h>static void printchar(char **str, int c){	extern int putchar(int c);		if (str) {		**str = c;		++(*str);	}	else (void)putchar(c);}#define PAD_RIGHT 1#define PAD_ZERO 2static 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 12static 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);}static int print(char **out, const char *format, va_list args ){	register int width, pad;	register int pc = 0;	char scr[2];	for (; *format != 0; ++format) {		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 *)va_arg( args, int );				pc += prints (out, s?s:"(null)", width, pad);				continue;			}			if( *format == 'd' ) {				pc += printi (out, va_arg( args, int ), 10, 1, width, pad, 'a');				continue;			}			if( *format == 'x' ) {				pc += printi (out, va_arg( args, int ), 16, 0, width, pad, 'a');				continue;			}			if( *format == 'X' ) {				pc += printi (out, va_arg( args, int ), 16, 0, width, pad, 'A');				continue;			}			if( *format == 'u' ) {				pc += printi (out, va_arg( args, int ), 10, 0, width, pad, 'a');				continue;			}			if( *format == 'c' ) {				/* char are converted to int then pushed on the stack */				scr[0] = (char)va_arg( args, int );				scr[1] = '\0';				pc += prints (out, scr, width, pad);				continue;			}		}		else {		out:			printchar (out, *format);			++pc;		}	}	if (out) **out = '\0';	va_end( args );	return pc;}int printf(const char *format, ...){        va_list args;                va_start( args, format );        return print( 0, format, args );}int sprintf(char *out, const char *format, ...){        va_list args;                va_start( args, format );        return print( &out, format, args );}#ifdef TEST_PRINTFint main(void){	char *ptr = "Hello world!";	char *np = 0;	int i = 5;	unsigned int bs = sizeof(int)*8;	int mi;	char buf[80];	mi = (1 << (bs-1)) + 1;	printf("%s\n", ptr);	printf("printf test\n");	printf("%s is null pointer\n", np);	printf("%d = 5\n", i);	printf("%d = - max int\n", mi);	printf("char %c = 'a'\n", 'a');	printf("hex %x = ff\n", 0xff);	printf("hex %02x = 00\n", 0);	printf("signed %d = unsigned %u = hex %x\n", -3, -3, -3);	printf("%d %s(s)%", 0, "message");	printf("\n");	printf("%d %s(s) with %%\n", 0, "message");	sprintf(buf, "justif: \"%-10s\"\n", "left"); printf("%s", buf);	sprintf(buf, "justif: \"%10s\"\n", "right"); printf("%s", buf);	sprintf(buf, " 3: %04d zero padded\n", 3); printf("%s", buf);	sprintf(buf, " 3: %-4d left justif.\n", 3); printf("%s", buf);	sprintf(buf, " 3: %4d right justif.\n", 3); printf("%s", buf);	sprintf(buf, "-3: %04d zero padded\n", -3); printf("%s", buf);	sprintf(buf, "-3: %-4d left justif.\n", -3); printf("%s", buf);	sprintf(buf, "-3: %4d right justif.\n", -3); printf("%s", buf);	return 0;}/* * 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