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/* Charset name normalization.
Copyright (C) 2001-2018 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@cygnus.com>, 2001.
The GNU C Library 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 2.1 of the License, or (at your option) any later version.
The GNU C Library 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 the GNU C Library; if not, see
<http://www.gnu.org/licenses/>. */
#include <ctype.h>
#include <locale.h>
#include <stdbool.h>
#include <string.h>
#include <sys/stat.h>
#include <stdlib.h>
#include "gconv_int.h"
/* An iconv encoding is in the form of a triplet, with parts separated by
a '/' character. The first part is the standard name, the second part is
the character set, and the third part is the error handler. If the first
part is sufficient to identify both the standard and the character set
then the second part can be empty e.g. UTF-8//. If the first part is not
sufficient to identify both the standard and the character set then the
second part is required e.g. ISO-10646/UTF8/. If neither the first or
second parts are provided e.g. //, then the current locale is used.
The actual values used in the first and second parts are not entirely
relevant to the implementation. The values themselves are used in a hash
table to lookup modules and so the naming convention of the first two parts
is somewhat arbitrary and only helps locate the entries in the cache.
The third part is the error handler and is comprised of a ',' or '/'
separated list of suffixes. Currently, we support "TRANSLIT" for
transliteration and "IGNORE" for ignoring conversion errors due to
unrecognized input characters. */
#define GCONV_TRIPLE_SEPARATOR "/"
#define GCONV_SUFFIX_SEPARATOR ","
#define GCONV_TRANSLIT_SUFFIX "TRANSLIT"
#define GCONV_IGNORE_ERRORS_SUFFIX "IGNORE"
/* This function copies in-order, characters from the source 's' that are
either alpha-numeric or one in one of these: "_-.,:/" - into the destination
'wp' while dropping all other characters. In the process, it converts all
alphabetical characters to upper case. It then appends up to two '/'
characters so that the total number of '/'es in the destination is 2. */
static inline void __attribute__ ((unused, always_inline))
strip (char *wp, const char *s)
{
int slash_count = 0;
while (*s != '\0')
{
if (__isalnum_l (*s, _nl_C_locobj_ptr)
|| *s == '_' || *s == '-' || *s == '.' || *s == ',' || *s == ':')
*wp++ = __toupper_l (*s, _nl_C_locobj_ptr);
else if (*s == '/')
{
if (++slash_count == 3)
break;
*wp++ = '/';
}
++s;
}
while (slash_count++ < 2)
*wp++ = '/';
*wp = '\0';
}
static inline char * __attribute__ ((unused, always_inline))
upstr (char *dst, const char *str)
{
char *cp = dst;
while ((*cp++ = __toupper_l (*str++, _nl_C_locobj_ptr)) != '\0')
/* nothing */;
return dst;
}