asnprintf.c

打魔兽战网的都知道他是什么

/*
 * Copyright (C) 2005 Olaf Freyer ([e-mail])
 * 
 * Based upon lib/vsnprintf.c from the linux kernel sources
 * 
 *  Copyright (C) 1991, 1992  Linus Torvalds
 * vsprintf.c -- Lars Wirzenius & Linus Torvalds. *
 *
 * Wirzenius wrote this portably, Torvalds fucked it up :-)
 * 
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU 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 General Public License for more details.
 *
 * You should have received a copy of the GNU 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.
 */


#include "common/setup_before.h"
#include <ctype.h>
#include <stdio.h>
#ifdef HAVE_STRING_H
# include <string.h>
#else
# ifdef HAVE_STRINGS_H
#  include <strings.h>
# endif
#endif
#include "compat/uint.h"
#include "asnprintf.h"
#include "common/setup_after.h"

static int skip_atoi(const char **s)
{
	int i=0;

	while (isdigit(**s))
		i = i*10 + *((*s)++) - '0';
	return i;
}

t_uint32 do_div(t_uint64 *n, t_uint32 base)
{
	t_uint32 remainder = *n % base;
	*n = *n / base;
	return remainder;
}

static char * number(char * buf, char * end, t_uint64 num, int base, int size, int precision, int type)
{
	char c,sign,tmp[66];
	const char *digits;
	static const char small_digits[] = "0123456789abcdefghijklmnopqrstuvwxyz";
	static const char large_digits[] = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";
	int i;

	digits = (type & LARGE) ? large_digits : small_digits;
	if (type & LEFT)
		type &= ~ZEROPAD;
	if (base < 2 || base > 36)
		return NULL;
	c = (type & ZEROPAD) ? '0' : ' ';
	sign = 0;
	if (type & SIGN) {
		if ((t_int64) num < 0) {
			sign = '-';
			num = - (t_int64) num;
			size--;
		} else if (type & PLUS) {
			sign = '+';
			size--;
		} else if (type & SPACE) {
			sign = ' ';
			size--;
		}
	}
	if (type & SPECIAL) {
		if (base == 16)
			size -= 2;
		else if (base == 8)
			size--;
	}
	i = 0;
	if (num == 0)
		tmp[i++]='0';
	else while (num != 0)
		tmp[i++] = digits[do_div(&num,base)];
	if (i > precision)
		precision = i;
	size -= precision;
	if (!(type&(ZEROPAD+LEFT))) {
		while(size-->0) {
			if (buf <= end)
				*buf = ' ';
			++buf;
		}
	}
	if (sign) {
		if (buf <= end)
			*buf = sign;
		++buf;
	}
	if (type & SPECIAL) {
		if (base==8) {
			if (buf <= end)
				*buf = '0';
			++buf;
		} else if (base==16) {
			if (buf <= end)
				*buf = '0';
			++buf;
			if (buf <= end)
				*buf = digits[33];
			++buf;
		}
	}
	if (!(type & LEFT)) {
		while (size-- > 0) {
			if (buf <= end)
				*buf = c;
			++buf;
		}
	}
	while (i < precision--) {
		if (buf <= end)
			*buf = '0';
		++buf;
	}
	while (i-- > 0) {
		if (buf <= end)
			*buf = tmp[i];
		++buf;
	}
	while (size-- > 0) {
		if (buf <= end)
			*buf = ' ';
		++buf;
	}
	return buf;
}

int vasnprintf(char *buf, size_t size, t_fmtentry *entries, unsigned entlen, const char *fmt, va_list args)
{
	int len;
	t_uint64 num;
	int i, base;
	char *str, *end, c;
	const char *s;

	int flags;		/* flags to number() */

	int field_width;	/* width of output field */
	int precision;		/* min. # of digits for integers; max
				   number of chars for from string */
	int qualifier;		/* 'h', 'l', or 'L' for integer fields */
				/* 'z' support added 23/7/1999 S.H.    */
				/* 'z' changed to 'Z' --davidm 1/25/99 */
	unsigned fmtno = 0;


	/* Reject out-of-range values early */
	if ((int) size < 0)
		return 0;

	str = buf;
	end = buf + size - 1;
/*
	if (end < buf - 1) {
		end = ((void *) -1);
		size = end - buf + 1;
	}
*/
	for (; *fmt; ++fmt) {
		t_fmtentry* const fmtent = entries + fmtno;

		if (*fmt != '%')
			continue;

		if (fmtno >= entlen) return -1;
		fmtent->trans = str;
		fmtent->fmt = fmt;
		fmtno++;

		/* process flags */
		flags = 0;
		repeat:
			++fmt;		/* this also skips first '%' */
			switch (*fmt) {
				case '-': flags |= LEFT; goto repeat;
				case '+': flags |= PLUS; goto repeat;
				case ' ': flags |= SPACE; goto repeat;
				case '#': flags |= SPECIAL; goto repeat;
				case '0': flags |= ZEROPAD; goto repeat;
			}

		/* get field width */
		field_width = -1;
		if (isdigit(*fmt))
			field_width = skip_atoi(&fmt);
		else if (*fmt == '*') {
			++fmt;
			/* it's the next argument */
			field_width = va_arg(args, int);
			if (field_width < 0) {
				field_width = -field_width;
				flags |= LEFT;
			}
		}

		/* get the precision */
		precision = -1;
		if (*fmt == '.') {
			++fmt;	
			if (isdigit(*fmt))
				precision = skip_atoi(&fmt);
			else if (*fmt == '*') {
				++fmt;
				/* it's the next argument */
				precision = va_arg(args, int);
			}
			if (precision < 0)
				precision = 0;
		}

		/* get the conversion qualifier */
		qualifier = -1;
		if (*fmt == 'h' || *fmt == 'l' || *fmt == 'L' ||
		    *fmt =='Z' || *fmt == 'z') {
			qualifier = *fmt;
			++fmt;
			if (qualifier == 'l' && *fmt == 'l') {
				qualifier = 'L';
				++fmt;
			}
		}

		/* default base */
		base = 10;

		switch (*fmt) {
			case 'c':
				if (!(flags & LEFT)) {
					while (--field_width > 0) {
						if (str > end)
							return -1;
						*str = ' ';
						++str;
					}
				}
				c = (unsigned char) va_arg(args, int);
				if (str > end)
					return -1;
				*str = c;
				++str;
				while (--field_width > 0) {
					if (str > end)
						return -1;
					*str = ' ';
					++str;
				}
				fmtent->fmtlen = fmt - fmtent->fmt + 1;
				fmtent->translen = str - fmtent->trans;
				continue;

			case 's':
				s = va_arg(args, char *);
				if (!s)
					s = "<NULL>";

				len = strlen(s);
				if (len>precision) 
					len=precision;

				if (!(flags & LEFT)) {
					while (len < field_width--) {
						if (str > end)
							return -1;
						*str = ' ';
						++str;
					}
				}
				for (i = 0; i < len; ++i) {
					if (str > end)
						return -1;
					*str = *s;
					++str; ++s;
				}
				while (len < field_width--) {
					if (str > end)
						return -1;
					*str = ' ';
					++str;
				}
				fmtent->fmtlen = fmt - fmtent->fmt + 1;
				fmtent->translen = str - fmtent->trans;
				continue;

			case 'p':
				if (field_width == -1) {
					field_width = 2*sizeof(void *);
					flags |= ZEROPAD;
				}
				str = number(str, end,
						(unsigned long) va_arg(args, void *),
						16, field_width, precision, flags);
				if (str > end) return -1;
				fmtent->fmtlen = fmt - fmtent->fmt + 1;
				fmtent->translen = str - fmtent->trans;
				continue;


			case 'n':
				/* FIXME:
				* What does C99 say about the overflow case here? */
				if (qualifier == 'l') {
					long * ip = va_arg(args, long *);
					*ip = (str - buf);
				} else if (qualifier == 'Z' || qualifier == 'z') {
					size_t * ip = va_arg(args, size_t *);
					*ip = (str - buf);
				} else {
					int * ip = va_arg(args, int *);
					*ip = (str - buf);
				}
				fmtent->fmtlen = fmt - fmtent->fmt + 1;
				fmtent->translen = str - fmtent->trans;
				continue;

			case '%':
				if (str > end)
					return -1;
				*str = '%';
				++str;
				fmtent->fmtlen = fmt - fmtent->fmt + 1;
				fmtent->translen = str - fmtent->trans;
				continue;

				/* integer number formats - set up the flags and "break" */
			case 'o':
				base = 8;
				break;

			case 'X':
				flags |= LARGE;
			case 'x':
				base = 16;
				break;

			case 'd':
			case 'i':
				flags |= SIGN;
			case 'u':
				break;

			default:
				if (str > end)
					return -1;
				*str = '%';
				++str;
				if (*fmt) {
					if (str > end)
						return -1;
					*str = *fmt;
					++str;
				} else {
					--fmt;
				}
				fmtent->fmtlen = fmt - fmtent->fmt + 1;
				fmtent->translen = str - fmtent->trans;
				continue;
		}
		if (qualifier == 'L')
			num = va_arg(args, long long);
		else if (qualifier == 'l') {
			num = va_arg(args, unsigned long);
			if (flags & SIGN)
				num = (signed long) num;
		} else if (qualifier == 'Z' || qualifier == 'z') {
			num = va_arg(args, size_t);
		} else if (qualifier == 'h') {
			num = (unsigned short) va_arg(args, int);
			if (flags & SIGN)
				num = (signed short) num;
		} else {
			num = va_arg(args, unsigned int);
			if (flags & SIGN)
				num = (signed int) num;
		}
		str = number(str, end, num, base,
				field_width, precision, flags);
		if (str > end) return -1;
		fmtent->fmtlen = fmt - fmtent->fmt + 1;
		fmtent->translen = str - fmtent->trans;
	}
	if (str <= end)
		*str = '\0';
	/* the trailing null byte doesn't count towards the total
	* ++str;
	*/
	return str - buf;
}

int asnprintf(char * buf, size_t size, t_fmtentry *entries, unsigned entlen, const char *fmt, ...)
{
	va_list args;
	int i;

	VA_START(args, fmt);
	i=vasnprintf(buf,size,entries,entlen,fmt,args);
	va_end(args);
	return i;
}