/*
 * Copyright (c) 2000-2001, Boris Popov
 * 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 acknowledgement:
 *    This product includes software developed by Boris Popov.
 * 4. Neither the name of the author nor the names of any co-contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * 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.
 *
 * $Id: nls.c,v 1.9 2001/08/22 03:31:36 bp Exp $
 */

#include <sys/types.h>
#include <sys/iconv.h>
#include <sys/sysctl.h>
#include <ctype.h>
#ifndef APPLE
#include <dlfcn.h>
#endif
#include <errno.h>
#include <stdio.h>
#include <strings.h>
#include <stdlib.h>
#include <locale.h>
#include <err.h>
#include <netsmb/smb_lib.h>

/*
 * prototype iconv* functions
 */
typedef void *iconv_t;

static iconv_t (*my_iconv_open)(const char *, const char *);
static size_t(*my_iconv)(iconv_t, const char **, size_t *, char **, size_t *);
static int(*my_iconv_close)(iconv_t);

u_char nls_lower[256];
u_char nls_upper[256];

static iconv_t nls_toext, nls_toloc;
static int iconv_loaded;
static void *iconv_lib;

int
nls_setlocale(const char *name)
{
	int i;

	if (setlocale(LC_CTYPE, name) == NULL) {
		warnx("can't set locale '%s'\n", name);
		return EINVAL;
	}
	for (i = 0; i < 256; i++) {
		nls_lower[i] = tolower(i);
		nls_upper[i] = toupper(i);
	}
	return 0;
}

int
nls_setrecode(const char *local, const char *external)
{
#ifdef APPLE
	return ENOENT;
#else
	iconv_t icd;

	if (iconv_loaded == 2)
		return ENOENT;
	else if (iconv_loaded == 0) {
		iconv_loaded++;
		iconv_lib = dlopen("libiconv.so", RTLD_LAZY | RTLD_GLOBAL);
		if (iconv_lib == NULL) {
			warn("Unable to load iconv library: %s\n", dlerror());
			iconv_loaded++;
			return ENOENT;
		}
		my_iconv_open = dlsym(iconv_lib, "iconv_open");
		my_iconv = dlsym(iconv_lib, "iconv");
		my_iconv_close = dlsym(iconv_lib, "iconv_close");
	}
	if (nls_toext)
		my_iconv_close(nls_toext);
	if (nls_toloc)
		my_iconv_close(nls_toloc);
	nls_toext = nls_toloc = (iconv_t)0;
	icd = my_iconv_open(external, local);
	if (icd == (iconv_t)-1)
		return errno;
	nls_toext = icd;
	icd = my_iconv_open(local, external);
	if (icd == (iconv_t)-1) {
		my_iconv_close(nls_toext);
		nls_toext = (iconv_t)0;
		return errno;
	}
	nls_toloc = icd;
	return 0;
#endif
}

char *
nls_str_toloc(char *dst, const char *src)
{
	char *p = dst;
	int inlen, outlen;

	if (!iconv_loaded)
		return strcpy(dst, src);

	if (nls_toloc == (iconv_t)0)
		return strcpy(dst, src);
	inlen = outlen = strlen(src);
	my_iconv(nls_toloc, NULL, NULL, &p, &outlen);
	my_iconv(nls_toloc, &src, &inlen, &p, &outlen);
	*p = 0;
	return dst;
}

char *
nls_str_toext(char *dst, const char *src)
{
	char *p = dst;
	int inlen, outlen;

	if (!iconv_loaded)
		return strcpy(dst, src);

	if (nls_toext == (iconv_t)0)
		return strcpy(dst, src);
	inlen = outlen = strlen(src);
	my_iconv(nls_toext, NULL, NULL, &p, &outlen);
	my_iconv(nls_toext, &src, &inlen, &p, &outlen);
	*p = 0;
	return dst;
}

void *
nls_mem_toloc(void *dst, const void *src, int size)
{
	char *p = dst;
	const char *s = src;
	int inlen, outlen;

	if (!iconv_loaded)
		return memcpy(dst, src, size);

	if (size == 0)
		return NULL;

	if (nls_toloc == (iconv_t)0)
		return memcpy(dst, src, size);
	inlen = outlen = size;
	my_iconv(nls_toloc, NULL, NULL, &p, &outlen);
	my_iconv(nls_toloc, &s, &inlen, &p, &outlen);
	return dst;
}

void *
nls_mem_toext(void *dst, const void *src, int size)
{
	char *p = dst;
	const char *s = src;
	int inlen, outlen;

	if (size == 0)
		return NULL;

	if (!iconv_loaded || nls_toext == (iconv_t)0)
		return memcpy(dst, src, size);

	inlen = outlen = size;
	my_iconv(nls_toext, NULL, NULL, &p, &outlen);
	my_iconv(nls_toext, &s, &inlen, &p, &outlen);
	return dst;
}

char *
nls_str_upper(char *dst, const char *src)
{
	char *p = dst;

	while (*src)
		*dst++ = toupper(*src++);
	*dst = 0;
	return p;
}

char *
nls_str_lower(char *dst, const char *src)
{
	char *p = dst;

	while (*src)
		*dst++ = tolower(*src++);
	*dst = 0;
	return p;
}