glibc/iconv/iconv_open.c

90 lines
2.3 KiB
C

/* Get descriptor for character set conversion.
Copyright (C) 1997, 1998 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public License as
published by the Free Software Foundation; either version 2 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
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB. If not,
write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
#include <ctype.h>
#include <errno.h>
#include <iconv.h>
#include <stdlib.h>
#include <string.h>
#include <gconv_int.h>
static inline void
strip (char *wp, const char *s)
{
int slash_count = 0;
while (*s != '\0')
{
if (isalnum (*s) || *s == '_' || *s == '-' || *s == '.')
*wp++ = *s;
else if (*s == '/')
{
if (++slash_count == 3)
break;
*wp++ = '/';
}
++s;
}
while (slash_count++ < 2)
*wp++ = '/';
*wp = '\0';
}
iconv_t
iconv_open (const char *tocode, const char *fromcode)
{
char *tocode_conv;
char *fromcode_conv;
size_t tocode_len;
size_t fromcode_len;
gconv_t cd;
int res;
/* Normalize the name. We remove all characters beside alpha-numeric,
'_', '-', '/', and '.'. */
tocode_len = strlen (tocode);
tocode_conv = alloca (tocode_len + 3);
strip (tocode_conv, tocode);
fromcode_len = strlen (fromcode);
fromcode_conv = alloca (fromcode_len + 3);
strip (fromcode_conv, fromcode);
res = __gconv_open (tocode_conv[2] == '\0' ? tocode : tocode_conv,
fromcode_conv[2] == '\0' ? fromcode : fromcode_conv,
&cd);
if (res != GCONV_OK)
{
/* We must set the error number according to the specs. */
if (res == GCONV_NOCONV || res == GCONV_NODB)
__set_errno (EINVAL);
return (iconv_t) -1;
}
return (iconv_t) cd;
}