freebsd-dev/lib/libc/stdlib/strfmon.c
John Baldwin 1a4531bc98 Compute the correct size of the string to move forward.
Previously this was counting the amount of spare room at the start of
the buffer that the string needed to move forward and passing that as
the number of bytes to copy to memmove rather than the length of the
string to be copied.

In the strfmon test in the test suite this caused the memmove to
overflow the allocated buffer by one byte which CHERI caught.

Reported by:	CHERI
Reviewed by:	kevans
Obtained from:	CheriBSD
MFC after:	1 week
Sponsored by:	DARPA
Differential Revision:	https://reviews.freebsd.org/D26280
2020-09-02 20:04:26 +00:00

653 lines
16 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright (c) 2001 Alexey Zelkin <phantom@FreeBSD.org>
* All rights reserved.
*
* Copyright (c) 2011 The FreeBSD Foundation
* All rights reserved.
* Portions of this software were developed by David Chisnall
* under sponsorship from the FreeBSD Foundation.
*
* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``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 OR 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.
*
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/types.h>
#include <ctype.h>
#include <errno.h>
#include <limits.h>
#include <locale.h>
#include <monetary.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "xlocale_private.h"
/* internal flags */
#define NEED_GROUPING 0x01 /* print digits grouped (default) */
#define SIGN_POSN_USED 0x02 /* '+' or '(' usage flag */
#define LOCALE_POSN 0x04 /* use locale defined +/- (default) */
#define PARENTH_POSN 0x08 /* enclose negative amount in () */
#define SUPRESS_CURR_SYMBOL 0x10 /* suppress the currency from output */
#define LEFT_JUSTIFY 0x20 /* left justify */
#define USE_INTL_CURRENCY 0x40 /* use international currency symbol */
#define IS_NEGATIVE 0x80 /* is argument value negative ? */
/* internal macros */
#define PRINT(CH) do { \
if (dst >= s + maxsize) \
goto e2big_error; \
*dst++ = CH; \
} while (0)
#define PRINTS(STR) do { \
char *tmps = STR; \
while (*tmps != '\0') \
PRINT(*tmps++); \
} while (0)
#define GET_NUMBER(VAR) do { \
VAR = 0; \
while (isdigit((unsigned char)*fmt)) { \
if (VAR > INT_MAX / 10) \
goto e2big_error; \
VAR *= 10; \
VAR += *fmt - '0'; \
if (VAR < 0) \
goto e2big_error; \
fmt++; \
} \
} while (0)
#define GRPCPY(howmany) do { \
int i = howmany; \
while (i-- > 0) { \
avalue_size--; \
*--bufend = *(avalue+avalue_size+padded); \
} \
} while (0)
#define GRPSEP do { \
bufend -= thousands_sep_size; \
memcpy(bufend, thousands_sep, thousands_sep_size); \
groups++; \
} while (0)
static void __setup_vars(int, char *, char *, char *, char **);
static int __calc_left_pad(int, char *);
static char *__format_grouped_double(double, int *, int, int, int);
static ssize_t
vstrfmon_l(char * __restrict s, size_t maxsize, locale_t loc,
const char * __restrict format, va_list ap)
{
char *dst; /* output destination pointer */
const char *fmt; /* current format poistion pointer */
struct lconv *lc; /* pointer to lconv structure */
char *asciivalue; /* formatted double pointer */
int flags; /* formatting options */
int pad_char; /* padding character */
int pad_size; /* pad size */
int width; /* field width */
int left_prec; /* left precision */
int right_prec; /* right precision */
double value; /* just value */
char space_char = ' '; /* space after currency */
char cs_precedes, /* values gathered from struct lconv */
sep_by_space,
sign_posn,
*signstr,
*currency_symbol;
char *tmpptr; /* temporary vars */
int sverrno;
FIX_LOCALE(loc);
lc = localeconv_l(loc);
dst = s;
fmt = format;
asciivalue = NULL;
currency_symbol = NULL;
pad_size = 0;
while (*fmt) {
/* pass nonformating characters AS IS */
if (*fmt != '%')
goto literal;
/* '%' found ! */
/* "%%" mean just '%' */
if (*(fmt+1) == '%') {
fmt++;
literal:
PRINT(*fmt++);
continue;
}
/* set up initial values */
flags = (NEED_GROUPING|LOCALE_POSN);
pad_char = ' '; /* padding character is "space" */
left_prec = -1; /* no left precision specified */
right_prec = -1; /* no right precision specified */
width = -1; /* no width specified */
value = 0; /* we have no value to print now */
/* Flags */
while (1) {
switch (*++fmt) {
case '=': /* fill character */
pad_char = *++fmt;
if (pad_char == '\0')
goto format_error;
continue;
case '^': /* not group currency */
flags &= ~(NEED_GROUPING);
continue;
case '+': /* use locale defined signs */
if (flags & SIGN_POSN_USED)
goto format_error;
flags |= (SIGN_POSN_USED|LOCALE_POSN);
continue;
case '(': /* enclose negatives with () */
if (flags & SIGN_POSN_USED)
goto format_error;
flags |= (SIGN_POSN_USED|PARENTH_POSN);
continue;
case '!': /* suppress currency symbol */
flags |= SUPRESS_CURR_SYMBOL;
continue;
case '-': /* alignment (left) */
flags |= LEFT_JUSTIFY;
continue;
default:
break;
}
break;
}
/* field Width */
if (isdigit((unsigned char)*fmt)) {
GET_NUMBER(width);
/* Do we have enough space to put number with
* required width ?
*/
if ((unsigned int)width >= maxsize - (dst - s))
goto e2big_error;
}
/* Left precision */
if (*fmt == '#') {
if (!isdigit((unsigned char)*++fmt))
goto format_error;
GET_NUMBER(left_prec);
if ((unsigned int)left_prec >= maxsize - (dst - s))
goto e2big_error;
}
/* Right precision */
if (*fmt == '.') {
if (!isdigit((unsigned char)*++fmt))
goto format_error;
GET_NUMBER(right_prec);
if ((unsigned int)right_prec >= maxsize - (dst - s) -
left_prec)
goto e2big_error;
}
/* Conversion Characters */
switch (*fmt++) {
case 'i': /* use internaltion currency format */
flags |= USE_INTL_CURRENCY;
break;
case 'n': /* use national currency format */
flags &= ~(USE_INTL_CURRENCY);
break;
default: /* required character is missing or
premature EOS */
goto format_error;
}
if (currency_symbol != NULL)
free(currency_symbol);
if (flags & USE_INTL_CURRENCY) {
currency_symbol = strdup(lc->int_curr_symbol);
if (currency_symbol != NULL)
space_char = *(currency_symbol+3);
} else
currency_symbol = strdup(lc->currency_symbol);
if (currency_symbol == NULL)
goto end_error; /* ENOMEM. */
/* value itself */
value = va_arg(ap, double);
/* detect sign */
if (value < 0) {
flags |= IS_NEGATIVE;
value = -value;
}
/* fill left_prec with amount of padding chars */
if (left_prec >= 0) {
pad_size = __calc_left_pad((flags ^ IS_NEGATIVE),
currency_symbol) -
__calc_left_pad(flags, currency_symbol);
if (pad_size < 0)
pad_size = 0;
}
if (asciivalue != NULL)
free(asciivalue);
asciivalue = __format_grouped_double(value, &flags,
left_prec, right_prec, pad_char);
if (asciivalue == NULL)
goto end_error; /* errno already set */
/* to ENOMEM by malloc() */
/* set some variables for later use */
__setup_vars(flags, &cs_precedes, &sep_by_space,
&sign_posn, &signstr);
/*
* Description of some LC_MONETARY's values:
*
* p_cs_precedes & n_cs_precedes
*
* = 1 - $currency_symbol precedes the value
* for a monetary quantity with a non-negative value
* = 0 - symbol succeeds the value
*
* p_sep_by_space & n_sep_by_space
*
* = 0 - no space separates $currency_symbol
* from the value for a monetary quantity with a
* non-negative value
* = 1 - space separates the symbol from the value
* = 2 - space separates the symbol and the sign string,
* if adjacent.
*
* p_sign_posn & n_sign_posn
*
* = 0 - parentheses enclose the quantity and the
* $currency_symbol
* = 1 - the sign string precedes the quantity and the
* $currency_symbol
* = 2 - the sign string succeeds the quantity and the
* $currency_symbol
* = 3 - the sign string precedes the $currency_symbol
* = 4 - the sign string succeeds the $currency_symbol
*
*/
tmpptr = dst;
while (pad_size-- > 0)
PRINT(' ');
if (sign_posn == 0 && (flags & IS_NEGATIVE))
PRINT('(');
if (cs_precedes == 1) {
if (sign_posn == 1 || sign_posn == 3) {
PRINTS(signstr);
if (sep_by_space == 2) /* XXX: ? */
PRINT(' ');
}
if (!(flags & SUPRESS_CURR_SYMBOL)) {
PRINTS(currency_symbol);
if (sign_posn == 4) {
if (sep_by_space == 2)
PRINT(space_char);
PRINTS(signstr);
if (sep_by_space == 1)
PRINT(' ');
} else if (sep_by_space == 1)
PRINT(space_char);
}
} else if (sign_posn == 1)
PRINTS(signstr);
PRINTS(asciivalue);
if (cs_precedes == 0) {
if (sign_posn == 3) {
if (sep_by_space == 1)
PRINT(' ');
PRINTS(signstr);
}
if (!(flags & SUPRESS_CURR_SYMBOL)) {
if ((sign_posn == 3 && sep_by_space == 2)
|| (sep_by_space == 1
&& (sign_posn == 0
|| sign_posn == 1
|| sign_posn == 2
|| sign_posn == 4)))
PRINT(space_char);
PRINTS(currency_symbol); /* XXX: len */
if (sign_posn == 4) {
if (sep_by_space == 2)
PRINT(' ');
PRINTS(signstr);
}
}
}
if (sign_posn == 2) {
if (sep_by_space == 2)
PRINT(' ');
PRINTS(signstr);
}
if (sign_posn == 0 && (flags & IS_NEGATIVE))
PRINT(')');
if (dst - tmpptr < width) {
if (flags & LEFT_JUSTIFY) {
while (dst - tmpptr < width)
PRINT(' ');
} else {
pad_size = dst-tmpptr;
memmove(tmpptr + width-pad_size, tmpptr,
pad_size);
memset(tmpptr, ' ', width-pad_size);
dst += width-pad_size;
}
}
}
PRINT('\0');
free(asciivalue);
free(currency_symbol);
return (dst - s - 1); /* return size of put data except trailing '\0' */
e2big_error:
errno = E2BIG;
goto end_error;
format_error:
errno = EINVAL;
end_error:
sverrno = errno;
if (asciivalue != NULL)
free(asciivalue);
if (currency_symbol != NULL)
free(currency_symbol);
errno = sverrno;
return (-1);
}
ssize_t
strfmon_l(char * __restrict s, size_t maxsize, locale_t loc, const char * __restrict format,
...)
{
size_t ret;
va_list ap;
va_start(ap, format);
ret = vstrfmon_l(s, maxsize, loc, format, ap);
va_end(ap);
return ret;
}
ssize_t
strfmon(char * __restrict s, size_t maxsize, const char * __restrict format,
...)
{
size_t ret;
va_list ap;
va_start(ap, format);
ret = vstrfmon_l(s, maxsize, __get_locale(), format, ap);
va_end(ap);
return ret;
}
static void
__setup_vars(int flags, char *cs_precedes, char *sep_by_space,
char *sign_posn, char **signstr) {
struct lconv *lc = localeconv();
if ((flags & IS_NEGATIVE) && (flags & USE_INTL_CURRENCY)) {
*cs_precedes = lc->int_n_cs_precedes;
*sep_by_space = lc->int_n_sep_by_space;
*sign_posn = (flags & PARENTH_POSN) ? 0 : lc->int_n_sign_posn;
*signstr = (lc->negative_sign[0] == '\0') ? "-"
: lc->negative_sign;
} else if (flags & USE_INTL_CURRENCY) {
*cs_precedes = lc->int_p_cs_precedes;
*sep_by_space = lc->int_p_sep_by_space;
*sign_posn = (flags & PARENTH_POSN) ? 0 : lc->int_p_sign_posn;
*signstr = lc->positive_sign;
} else if (flags & IS_NEGATIVE) {
*cs_precedes = lc->n_cs_precedes;
*sep_by_space = lc->n_sep_by_space;
*sign_posn = (flags & PARENTH_POSN) ? 0 : lc->n_sign_posn;
*signstr = (lc->negative_sign[0] == '\0') ? "-"
: lc->negative_sign;
} else {
*cs_precedes = lc->p_cs_precedes;
*sep_by_space = lc->p_sep_by_space;
*sign_posn = (flags & PARENTH_POSN) ? 0 : lc->p_sign_posn;
*signstr = lc->positive_sign;
}
/* Set defult values for unspecified information. */
if (*cs_precedes != 0)
*cs_precedes = 1;
if (*sep_by_space == CHAR_MAX)
*sep_by_space = 0;
if (*sign_posn == CHAR_MAX)
*sign_posn = 0;
}
static int
__calc_left_pad(int flags, char *cur_symb) {
char cs_precedes, sep_by_space, sign_posn, *signstr;
int left_chars = 0;
__setup_vars(flags, &cs_precedes, &sep_by_space, &sign_posn, &signstr);
if (cs_precedes != 0) {
left_chars += strlen(cur_symb);
if (sep_by_space != 0)
left_chars++;
}
switch (sign_posn) {
case 1:
left_chars += strlen(signstr);
break;
case 3:
case 4:
if (cs_precedes != 0)
left_chars += strlen(signstr);
}
return (left_chars);
}
static int
get_groups(int size, char *grouping) {
int chars = 0;
if (*grouping == CHAR_MAX || *grouping <= 0) /* no grouping ? */
return (0);
while (size > (int)*grouping) {
chars++;
size -= (int)*grouping++;
/* no more grouping ? */
if (*grouping == CHAR_MAX)
break;
/* rest grouping with same value ? */
if (*grouping == 0) {
chars += (size - 1) / *(grouping - 1);
break;
}
}
return (chars);
}
/* convert double to locale-encoded string */
static char *
__format_grouped_double(double value, int *flags,
int left_prec, int right_prec, int pad_char) {
char *rslt;
char *avalue;
int avalue_size;
size_t bufsize;
char *bufend;
int padded;
struct lconv *lc = localeconv();
char *grouping;
const char *decimal_point;
const char *thousands_sep;
size_t decimal_point_size;
size_t thousands_sep_size;
int groups = 0;
grouping = lc->mon_grouping;
decimal_point = lc->mon_decimal_point;
if (*decimal_point == '\0')
decimal_point = lc->decimal_point;
thousands_sep = lc->mon_thousands_sep;
if (*thousands_sep == '\0')
thousands_sep = lc->thousands_sep;
decimal_point_size = strlen(decimal_point);
thousands_sep_size = strlen(thousands_sep);
/* fill left_prec with default value */
if (left_prec == -1)
left_prec = 0;
/* fill right_prec with default value */
if (right_prec == -1) {
if (*flags & USE_INTL_CURRENCY)
right_prec = lc->int_frac_digits;
else
right_prec = lc->frac_digits;
if (right_prec == CHAR_MAX) /* POSIX locale ? */
right_prec = 2;
}
if (*flags & NEED_GROUPING)
left_prec += get_groups(left_prec, grouping);
/* convert to string */
avalue_size = asprintf(&avalue, "%*.*f", left_prec + right_prec + 1,
right_prec, value);
if (avalue_size < 0)
return (NULL);
/* make sure that we've enough space for result string */
bufsize = avalue_size * (1 + thousands_sep_size) + decimal_point_size +
1;
rslt = calloc(1, bufsize);
if (rslt == NULL) {
free(avalue);
return (NULL);
}
bufend = rslt + bufsize - 1; /* reserve space for trailing '\0' */
/* skip spaces at beginning */
padded = 0;
while (avalue[padded] == ' ') {
padded++;
avalue_size--;
}
if (right_prec > 0) {
bufend -= right_prec;
memcpy(bufend, avalue + avalue_size+padded-right_prec,
right_prec);
bufend -= decimal_point_size;
memcpy(bufend, decimal_point, decimal_point_size);
avalue_size -= (right_prec + 1);
}
if ((*flags & NEED_GROUPING) &&
thousands_sep_size > 0 && /* XXX: need investigation */
*grouping != CHAR_MAX &&
*grouping > 0) {
while (avalue_size > (int)*grouping) {
GRPCPY(*grouping);
GRPSEP;
grouping++;
/* no more grouping ? */
if (*grouping == CHAR_MAX)
break;
/* rest grouping with same value ? */
if (*grouping == 0) {
grouping--;
while (avalue_size > *grouping) {
GRPCPY(*grouping);
GRPSEP;
}
}
}
if (avalue_size != 0)
GRPCPY(avalue_size);
padded -= groups;
} else {
bufend -= avalue_size;
memcpy(bufend, avalue+padded, avalue_size);
/* decrease assumed $decimal_point */
if (right_prec == 0)
padded -= decimal_point_size;
}
/* do padding with pad_char */
if (padded > 0) {
bufend -= padded;
memset(bufend, pad_char, padded);
}
bufsize = rslt + bufsize - bufend;
memmove(rslt, bufend, bufsize);
free(avalue);
return (rslt);
}