/*
* $Id: snprintf.c,v 1.18 2001/01/07 10:57:14 hno Exp $
*/
/* ====================================================================
* Copyright (c) 1995-1997 The Apache Group. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. 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.
*
* 3. All advertising materials mentioning features or use of this
* software must display the following acknowledgment:
* "This product includes software developed by the Apache Group
* for use in the Apache HTTP server project (http://www.apache.org/)."
*
* 4. The names "Apache Server" and "Apache Group" must not be used to
* endorse or promote products derived from this software without
* prior written permission.
*
* 5. Redistributions of any form whatsoever must retain the following
* acknowledgment:
* "This product includes software developed by the Apache Group
* for use in the Apache HTTP server project (http://www.apache.org/)."
*
* THIS SOFTWARE IS PROVIDED BY THE APACHE GROUP ``AS IS'' AND ANY
* EXPRESSED 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 APACHE GROUP OR
* ITS CONTRIBUTORS 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.
* ====================================================================
*
* This software consists of voluntary contributions made by many
* individuals on behalf of the Apache Group and was originally based
* on public domain software written at the National Center for
* Supercomputing Applications, University of Illinois, Urbana-Champaign.
* For more information on the Apache Group and the Apache HTTP server
* project, please see .
*
* This code is based on, and used with the permission of, the
* SIO stdio-replacement strx_* functions by Panos Tsirigotis
* for xinetd.
*/
#include "config.h"
#if !HAVE_SNPRINTF || !HAVE_VSNPRINTF
#include
#include
#include
#include
#include
#include
#include
#include
#ifdef HAVE_CVT
#define ap_ecvt ecvt
#define ap_fcvt fcvt
#define ap_gcvt gcvt
#else
/*
* cvt.c - IEEE floating point formatting routines for FreeBSD
* from GNU libc-4.6.27
*/
/*
* ap_ecvt converts to decimal
* the number of digits is specified by ndigit
* decpt is set to the position of the decimal point
* sign is set to 0 for positive, 1 for negative
*/
#define NDIG 80
static char *
ap_cvt(double arg, int ndigits, int *decpt, int *sign, int eflag)
{
register int r2;
double fi, fj;
register char *p, *p1;
static char buf[NDIG];
if (ndigits >= NDIG - 1)
ndigits = NDIG - 2;
r2 = 0;
*sign = 0;
p = &buf[0];
if (arg < 0) {
*sign = 1;
arg = -arg;
}
arg = modf(arg, &fi);
p1 = &buf[NDIG];
/*
* Do integer part
*/
if (fi != 0) {
p1 = &buf[NDIG];
while (fi != 0) {
fj = modf(fi / 10, &fi);
*--p1 = (int) ((fj + .03) * 10) + '0';
r2++;
}
while (p1 < &buf[NDIG])
*p++ = *p1++;
} else if (arg > 0) {
while ((fj = arg * 10) < 1) {
arg = fj;
r2--;
}
}
p1 = &buf[ndigits];
if (eflag == 0)
p1 += r2;
*decpt = r2;
if (p1 < &buf[0]) {
buf[0] = '\0';
return (buf);
}
while (p <= p1 && p < &buf[NDIG]) {
arg *= 10;
arg = modf(arg, &fj);
*p++ = (int) fj + '0';
}
if (p1 >= &buf[NDIG]) {
buf[NDIG - 1] = '\0';
return (buf);
}
p = p1;
*p1 += 5;
while (*p1 > '9') {
*p1 = '0';
if (p1 > buf)
++ * --p1;
else {
*p1 = '1';
(*decpt)++;
if (eflag == 0) {
if (p > buf)
*p = '0';
p++;
}
}
}
*p = '\0';
return (buf);
}
static char *
ap_ecvt(double arg, int ndigits, int *decpt, int *sign)
{
return (ap_cvt(arg, ndigits, decpt, sign, 1));
}
static char *
ap_fcvt(double arg, int ndigits, int *decpt, int *sign)
{
return (ap_cvt(arg, ndigits, decpt, sign, 0));
}
/*
* ap_gcvt - Floating output conversion to
* minimal length string
*/
static char *
ap_gcvt(double number, int ndigit, char *buf)
{
int sign, decpt;
register char *p1, *p2;
register int i;
p1 = ap_ecvt(number, ndigit, &decpt, &sign);
p2 = buf;
if (sign)
*p2++ = '-';
for (i = ndigit - 1; i > 0 && p1[i] == '0'; i--)
ndigit--;
if ((decpt >= 0 && decpt - ndigit > 4)
|| (decpt < 0 && decpt < -3)) { /* use E-style */
decpt--;
*p2++ = *p1++;
*p2++ = '.';
for (i = 1; i < ndigit; i++)
*p2++ = *p1++;
*p2++ = 'e';
if (decpt < 0) {
decpt = -decpt;
*p2++ = '-';
} else
*p2++ = '+';
if (decpt / 100 > 0)
*p2++ = decpt / 100 + '0';
if (decpt / 10 > 0)
*p2++ = (decpt % 100) / 10 + '0';
*p2++ = decpt % 10 + '0';
} else {
if (decpt <= 0) {
if (*p1 != '0')
*p2++ = '.';
while (decpt < 0) {
decpt++;
*p2++ = '0';
}
}
for (i = 1; i <= ndigit; i++) {
*p2++ = *p1++;
if (i == decpt)
*p2++ = '.';
}
if (ndigit < decpt) {
while (ndigit++ < decpt)
*p2++ = '0';
*p2++ = '.';
}
}
if (p2[-1] == '.')
p2--;
*p2 = '\0';
return (buf);
}
#endif /* HAVE_CVT */
typedef enum {
NO = 0, YES = 1
} boolean_e;
#define FALSE 0
#define TRUE 1
#define NUL '\0'
#define INT_NULL ((int *)0)
#define WIDE_INT long
typedef WIDE_INT wide_int;
typedef unsigned WIDE_INT u_wide_int;
typedef int bool_int;
#define S_NULL "(null)"
#define S_NULL_LEN 6
#define FLOAT_DIGITS 6
#define EXPONENT_LENGTH 10
/*
* NUM_BUF_SIZE is the size of the buffer used for arithmetic conversions
*
* XXX: this is a magic number; do not decrease it
*/
#define NUM_BUF_SIZE 512
/*
* Descriptor for buffer area
*/
struct buf_area {
char *buf_end;
char *nextb; /* pointer to next byte to read/write */
};
typedef struct buf_area buffy;
/*
* The INS_CHAR macro inserts a character in the buffer and writes
* the buffer back to disk if necessary
* It uses the char pointers sp and bep:
* sp points to the next available character in the buffer
* bep points to the end-of-buffer+1
* While using this macro, note that the nextb pointer is NOT updated.
*
* NOTE: Evaluation of the c argument should not have any side-effects
*/
#define INS_CHAR( c, sp, bep, cc ) \
{ \
if ( sp < bep ) \
{ \
*sp++ = c ; \
cc++ ; \
} \
}
#define NUM( c ) ( c - '0' )
#define STR_TO_DEC( str, num ) \
num = NUM( *str++ ) ; \
while ( xisdigit( *str ) ) \
{ \
num *= 10 ; \
num += NUM( *str++ ) ; \
}
/*
* This macro does zero padding so that the precision
* requirement is satisfied. The padding is done by
* adding '0's to the left of the string that is going
* to be printed.
*/
#define FIX_PRECISION( adjust, precision, s, s_len ) \
if ( adjust ) \
while ( s_len < precision ) \
{ \
*--s = '0' ; \
s_len++ ; \
}
/*
* Macro that does padding. The padding is done by printing
* the character ch.
*/
#define PAD( width, len, ch ) do \
{ \
INS_CHAR( ch, sp, bep, cc ) ; \
width-- ; \
} \
while ( width > len )
/*
* Prefix the character ch to the string str
* Increase length
* Set the has_prefix flag
*/
#define PREFIX( str, length, ch ) *--str = ch ; length++ ; has_prefix = YES
/*
* Convert num to its decimal format.
* Return value:
* - a pointer to a string containing the number (no sign)
* - len contains the length of the string
* - is_negative is set to TRUE or FALSE depending on the sign
* of the number (always set to FALSE if is_unsigned is TRUE)
*
* The caller provides a buffer for the string: that is the buf_end argument
* which is a pointer to the END of the buffer + 1 (i.e. if the buffer
* is declared as buf[ 100 ], buf_end should be &buf[ 100 ])
*/
static char *
conv_10(register wide_int num, register bool_int is_unsigned,
register bool_int * is_negative, char *buf_end, register int *len)
{
register char *p = buf_end;
register u_wide_int magnitude;
if (is_unsigned) {
magnitude = (u_wide_int) num;
*is_negative = FALSE;
} else {
*is_negative = (num < 0);
/*
* On a 2's complement machine, negating the most negative integer
* results in a number that cannot be represented as a signed integer.
* Here is what we do to obtain the number's magnitude:
* a. add 1 to the number
* b. negate it (becomes positive)
* c. convert it to unsigned
* d. add 1
*/
if (*is_negative) {
wide_int t = num + 1;
magnitude = ((u_wide_int) - t) + 1;
} else
magnitude = (u_wide_int) num;
}
/*
* We use a do-while loop so that we write at least 1 digit
*/
do {
register u_wide_int new_magnitude = magnitude / 10;
*--p = (char) (magnitude - new_magnitude * 10 + '0');
magnitude = new_magnitude;
}
while (magnitude);
*len = buf_end - p;
return (p);
}
/*
* Convert a floating point number to a string formats 'f', 'e' or 'E'.
* The result is placed in buf, and len denotes the length of the string
* The sign is returned in the is_negative argument (and is not placed
* in buf).
*/
static char *
conv_fp(register char format, register double num,
boolean_e add_dp, int precision, bool_int * is_negative, char *buf, int *len)
{
register char *s = buf;
register char *p;
int decimal_point;
if (format == 'f')
p = ap_fcvt(num, precision, &decimal_point, is_negative);
else /* either e or E format */
p = ap_ecvt(num, precision + 1, &decimal_point, is_negative);
/*
* Check for Infinity and NaN
*/
if (xisalpha(*p)) {
*len = strlen(strcpy(buf, p));
*is_negative = FALSE;
return (buf);
}
if (format == 'f') {
if (decimal_point <= 0) {
*s++ = '0';
if (precision > 0) {
*s++ = '.';
while (decimal_point++ < 0)
*s++ = '0';
} else if (add_dp)
*s++ = '.';
} else {
while (decimal_point-- > 0)
*s++ = *p++;
if (precision > 0 || add_dp)
*s++ = '.';
}
} else {
*s++ = *p++;
if (precision > 0 || add_dp)
*s++ = '.';
}
/*
* copy the rest of p, the NUL is NOT copied
*/
while (*p)
*s++ = *p++;
if (format != 'f') {
char temp[EXPONENT_LENGTH]; /* for exponent conversion */
int t_len;
bool_int exponent_is_negative;
*s++ = format; /* either e or E */
decimal_point--;
if (decimal_point != 0) {
p = conv_10((wide_int) decimal_point, FALSE, &exponent_is_negative,
&temp[EXPONENT_LENGTH], &t_len);
*s++ = exponent_is_negative ? '-' : '+';
/*
* Make sure the exponent has at least 2 digits
*/
if (t_len == 1)
*s++ = '0';
while (t_len--)
*s++ = *p++;
} else {
*s++ = '+';
*s++ = '0';
*s++ = '0';
}
}
*len = s - buf;
return (buf);
}
/*
* Convert num to a base X number where X is a power of 2. nbits determines X.
* For example, if nbits is 3, we do base 8 conversion
* Return value:
* a pointer to a string containing the number
*
* The caller provides a buffer for the string: that is the buf_end argument
* which is a pointer to the END of the buffer + 1 (i.e. if the buffer
* is declared as buf[ 100 ], buf_end should be &buf[ 100 ])
*/
static char *
conv_p2(register u_wide_int num, register int nbits,
char format, char *buf_end, register int *len)
{
register int mask = (1 << nbits) - 1;
register char *p = buf_end;
static char low_digits[] = "0123456789abcdef";
static char upper_digits[] = "0123456789ABCDEF";
register char *digits = (format == 'X') ? upper_digits : low_digits;
do {
*--p = digits[num & mask];
num >>= nbits;
}
while (num);
*len = buf_end - p;
return (p);
}
/*
* Do format conversion placing the output in buffer
*/
static int
format_converter(register buffy * odp, const char *fmt,
va_list ap)
{
register char *sp;
register char *bep;
register int cc = 0;
register int i;
register char *s = NULL;
char *q;
int s_len;
register int min_width = 0;
int precision = 0;
enum {
LEFT, RIGHT
} adjust;
char pad_char;
char prefix_char;
double fp_num;
wide_int i_num = (wide_int) 0;
u_wide_int ui_num;
char num_buf[NUM_BUF_SIZE];
char char_buf[2]; /* for printing %% and % */
/*
* Flag variables
*/
boolean_e is_long;
boolean_e alternate_form;
boolean_e print_sign;
boolean_e print_blank;
boolean_e adjust_precision;
boolean_e adjust_width;
bool_int is_negative;
sp = odp->nextb;
bep = odp->buf_end;
while (*fmt) {
if (*fmt != '%') {
INS_CHAR(*fmt, sp, bep, cc);
} else {
/*
* Default variable settings
*/
adjust = RIGHT;
alternate_form = print_sign = print_blank = NO;
pad_char = ' ';
prefix_char = NUL;
fmt++;
/*
* Try to avoid checking for flags, width or precision
*/
if (xisascii(*fmt) && !xislower(*fmt)) {
/*
* Recognize flags: -, #, BLANK, +
*/
for (;; fmt++) {
if (*fmt == '-')
adjust = LEFT;
else if (*fmt == '+')
print_sign = YES;
else if (*fmt == '#')
alternate_form = YES;
else if (*fmt == ' ')
print_blank = YES;
else if (*fmt == '0')
pad_char = '0';
else
break;
}
/*
* Check if a width was specified
*/
if (xisdigit(*fmt)) {
STR_TO_DEC(fmt, min_width);
adjust_width = YES;
} else if (*fmt == '*') {
min_width = va_arg(ap, int);
fmt++;
adjust_width = YES;
if (min_width < 0) {
adjust = LEFT;
min_width = -min_width;
}
} else
adjust_width = NO;
/*
* Check if a precision was specified
*
* XXX: an unreasonable amount of precision may be specified
* resulting in overflow of num_buf. Currently we
* ignore this possibility.
*/
if (*fmt == '.') {
adjust_precision = YES;
fmt++;
if (xisdigit(*fmt)) {
STR_TO_DEC(fmt, precision);
} else if (*fmt == '*') {
precision = va_arg(ap, int);
fmt++;
if (precision < 0)
precision = 0;
} else
precision = 0;
} else
adjust_precision = NO;
} else
adjust_precision = adjust_width = NO;
/*
* Modifier check
*/
if (*fmt == 'l') {
is_long = YES;
fmt++;
} else
is_long = NO;
/*
* Argument extraction and printing.
* First we determine the argument type.
* Then, we convert the argument to a string.
* On exit from the switch, s points to the string that
* must be printed, s_len has the length of the string
* The precision requirements, if any, are reflected in s_len.
*
* NOTE: pad_char may be set to '0' because of the 0 flag.
* It is reset to ' ' by non-numeric formats
*/
switch (*fmt) {
case 'u':
if (is_long)
i_num = va_arg(ap, u_wide_int);
else
i_num = (wide_int) va_arg(ap, unsigned int);
/*
* The rest also applies to other integer formats, so fall
* into that case.
*/
case 'd':
case 'i':
/*
* Get the arg if we haven't already.
*/
if ((*fmt) != 'u') {
if (is_long)
i_num = va_arg(ap, wide_int);
else
i_num = (wide_int) va_arg(ap, int);
};
s = conv_10(i_num, (*fmt) == 'u', &is_negative,
&num_buf[NUM_BUF_SIZE], &s_len);
FIX_PRECISION(adjust_precision, precision, s, s_len);
if (*fmt != 'u') {
if (is_negative)
prefix_char = '-';
else if (print_sign)
prefix_char = '+';
else if (print_blank)
prefix_char = ' ';
}
break;
case 'o':
if (is_long)
ui_num = va_arg(ap, u_wide_int);
else
ui_num = (u_wide_int) va_arg(ap, unsigned int);
s = conv_p2(ui_num, 3, *fmt,
&num_buf[NUM_BUF_SIZE], &s_len);
FIX_PRECISION(adjust_precision, precision, s, s_len);
if (alternate_form && *s != '0') {
*--s = '0';
s_len++;
}
break;
case 'x':
case 'X':
if (is_long)
ui_num = (u_wide_int) va_arg(ap, u_wide_int);
else
ui_num = (u_wide_int) va_arg(ap, unsigned int);
s = conv_p2(ui_num, 4, *fmt,
&num_buf[NUM_BUF_SIZE], &s_len);
FIX_PRECISION(adjust_precision, precision, s, s_len);
if (alternate_form && i_num != 0) {
*--s = *fmt; /* 'x' or 'X' */
*--s = '0';
s_len += 2;
}
break;
case 's':
s = va_arg(ap, char *);
if (s != NULL) {
s_len = strlen(s);
if (adjust_precision && precision < s_len)
s_len = precision;
} else {
s = S_NULL;
s_len = S_NULL_LEN;
}
pad_char = ' ';
break;
case 'f':
case 'e':
case 'E':
fp_num = va_arg(ap, double);
s = conv_fp(*fmt, fp_num, alternate_form,
(adjust_precision == NO) ? FLOAT_DIGITS : precision,
&is_negative, &num_buf[1], &s_len);
if (is_negative)
prefix_char = '-';
else if (print_sign)
prefix_char = '+';
else if (print_blank)
prefix_char = ' ';
break;
case 'g':
case 'G':
if (adjust_precision == NO)
precision = FLOAT_DIGITS;
else if (precision == 0)
precision = 1;
/* We use &num_buf[ 1 ], so that we have room for the sign */
s = ap_gcvt(va_arg(ap, double), precision, &num_buf[1]);
if (*s == '-')
prefix_char = *s++;
else if (print_sign)
prefix_char = '+';
else if (print_blank)
prefix_char = ' ';
s_len = strlen(s);
if (alternate_form && (q = strchr(s, '.')) == NULL)
s[s_len++] = '.';
if (*fmt == 'G' && (q = strchr(s, 'e')) != NULL)
*q = 'E';
break;
case 'c':
char_buf[0] = (char) (va_arg(ap, int));
s = &char_buf[0];
s_len = 1;
pad_char = ' ';
break;
case '%':
char_buf[0] = '%';
s = &char_buf[0];
s_len = 1;
pad_char = ' ';
break;
case 'n':
*(va_arg(ap, int *)) = cc;
break;
/*
* Always extract the argument as a "char *" pointer. We
* should be using "void *" but there are still machines
* that don't understand it.
* If the pointer size is equal to the size of an unsigned
* integer we convert the pointer to a hex number, otherwise
* we print "%p" to indicate that we don't handle "%p".
*/
case 'p':
ui_num = (u_wide_int) va_arg(ap, char *);
if (sizeof(char *) <= sizeof(u_wide_int))
s = conv_p2(ui_num, 4, 'x',
&num_buf[NUM_BUF_SIZE], &s_len);
else {
s = "%p";
s_len = 2;
}
pad_char = ' ';
break;
case NUL:
/*
* The last character of the format string was %.
* We ignore it.
*/
continue;
/*
* The default case is for unrecognized %'s.
* We print % to help the user identify what
* option is not understood.
* This is also useful in case the user wants to pass
* the output of format_converter to another function
* that understands some other % (like syslog).
* Note that we can't point s inside fmt because the
* unknown could be preceded by width etc.
*/
default:
char_buf[0] = '%';
char_buf[1] = *fmt;
s = char_buf;
s_len = 2;
pad_char = ' ';
break;
}
if (prefix_char != NUL) {
*--s = prefix_char;
s_len++;
}
if (adjust_width && adjust == RIGHT && min_width > s_len) {
if (pad_char == '0' && prefix_char != NUL) {
INS_CHAR(*s, sp, bep, cc)
s++;
s_len--;
min_width--;
}
PAD(min_width, s_len, pad_char);
}
/*
* Print the string s.
*/
for (i = s_len; i != 0; i--) {
INS_CHAR(*s, sp, bep, cc);
s++;
}
if (adjust_width && adjust == LEFT && min_width > s_len)
PAD(min_width, s_len, pad_char);
}
fmt++;
}
odp->nextb = sp;
return (cc);
}
/*
* This is the general purpose conversion function.
* Must be called with len >= 0, but we cannot assert() that
* because size_t is unsigned on some platforms
*/
static void
strx_printv(int *ccp, char *buf, size_t len, const char *format,
va_list ap)
{
buffy od;
int cc;
#if OLD_CODE
/*
* First initialize the descriptor
* Notice that if no length is given, we initialize buf_end to the
* highest possible address.
*/
od.buf_end = len ? &buf[len] : (char *) ~0;
#else
od.buf_end = &buf[len];
#endif
od.nextb = buf;
/*
* Do the conversion
*/
cc = format_converter(&od, format, ap);
if (len == 0 || od.nextb <= od.buf_end)
*(od.nextb) = '\0';
if (ccp)
*ccp = cc;
}
#endif
#if !HAVE_SNPRINTF
/*
* if len == 0, silently return
*/
int
snprintf(char *buf, size_t len, const char *format,...)
{
int cc = 0;
va_list ap;
va_start(ap, format);
if (len > 0)
strx_printv(&cc, buf, (len - 1), format, ap);
va_end(ap);
return (cc);
}
#endif
#if !HAVE_VSNPRINTF
/*
* if len == 0, silently return
*/
int
vsnprintf(char *buf, size_t len, const char *format, va_list ap)
{
int cc = 0;
if (len > 0)
strx_printv(&cc, buf, (len - 1), format, ap);
return (cc);
}
#endif