/*-
 * Copyright (c) 1994
 *	The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley
 * by Pace Willisson (pace@blitz.com).  The Rock Ridge Extension
 * Support code is derived from software contributed to Berkeley
 * by Atsushi Murai (amurai@spec.co.jp). Joliet support was added by
 * Joachim Kuebart (joki@kuebart.stuttgart.netsurf.de).
 *
 * 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. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
 *
 *	@(#)cd9660_util.c	8.3 (Berkeley) 12/5/94
 * $FreeBSD: src/sys/isofs/cd9660/cd9660_util.c,v 1.13.2.1 2001/02/27 12:36:34 sobomax Exp $
 */

#include <sys/param.h>
#include <sys/mount.h>
#include <sys/vnode.h>
#include <sys/iconv.h>

#include "iso.h"
#include "cd9660_mount.h"

extern struct iconv_functions *cd9660_iconv;

/*
 * Get one character out of an iso filename
 * Obey joliet_level
 * Return number of bytes consumed
 */
int
isochar(u_char *isofn, u_char *isoend, int joliet_level, u_short *c,
	int *clen, int flags, void *handle)
{
	size_t i, j, len;
	char inbuf[3], outbuf[3], *inp, *outp;

	*c = *isofn++;
	if (clen) *clen = 1;
	if (joliet_level == 0 || isofn == isoend) {
		/* (00) and (01) are one byte in Joliet, too */
		return 1;
	}

	if (flags & ISOFSMNT_KICONV && cd9660_iconv) {
		i = j = len = 2;
		inbuf[0]=(char)*(isofn - 1);
		inbuf[1]=(char)*isofn;
		inbuf[2]='\0';
		inp = inbuf;
		outp = outbuf;
		cd9660_iconv->convchr(handle, __DECONST(const char **, &inp),
		    &i, &outp, &j);
		len -= j;
		if (clen) *clen = len;
		*c = '\0';
		while(len--)
			*c |= (*(outp - len - 1) & 0xff) << (len << 3);
	} else {
		switch (*c) {
		default:
			*c = '?';
			break;
		case '\0':
			*c = *isofn;
			break;
		}
	}

	return 2;
}

/*
 * translate and compare a filename
 * returns (fn - isofn)
 * Note: Version number plus ';' may be omitted.
 */
int
isofncmp(u_char *fn, int fnlen, u_char *isofn, int isolen, int joliet_level,
	 int flags, void *handle, void *lhandle)
{
	int i, j;
	u_short c, d;
	u_char *fnend = fn + fnlen, *isoend = isofn + isolen;

	for (; fn < fnend; ) {
		d = sgetrune(fn, fnend - fn, __DECONST(const char **, &fn),
		    flags, lhandle);
		if (isofn == isoend)
			return d;
		isofn += isochar(isofn, isoend, joliet_level, &c, NULL, flags, handle);
		if (c == ';') {
			if (d != ';')
				return d;
			for (i = 0; fn < fnend; i = i * 10 + *fn++ - '0') {
				if (*fn < '0' || *fn > '9') {
					return -1;
				}
			}
			for (j = 0; isofn != isoend; j = j * 10 + c - '0')
				isofn += isochar(isofn, isoend,
						 joliet_level, &c,
						 NULL, flags, handle);
			return i - j;
		}
		if (c != d) {
			if (c >= 'A' && c <= 'Z') {
				if (c + ('a' - 'A') != d) {
					if (d >= 'a' && d <= 'z')
						return d - ('a' - 'A') - c;
					else
						return d - c;
				}
			} else
				return d - c;
		}
	}
	if (isofn != isoend) {
		isofn += isochar(isofn, isoend, joliet_level, &c, NULL, flags, handle);
		switch (c) {
		default:
			return -c;
		case '.':
			if (isofn != isoend) {
				isochar(isofn, isoend, joliet_level, &c,
					NULL, flags, handle);
				if (c == ';')
					return 0;
			}
			return -1;
		case ';':
			return 0;
		}
	}
	return 0;
}

/*
 * translate a filename of length > 0
 */
void
isofntrans(u_char *infn, int infnlen, u_char *outfn, u_short *outfnlen, int original,
	   int assoc, int joliet_level, int flags, void *handle)
{
	u_short c, d = '\0';
	u_char *outp = outfn, *infnend = infn + infnlen;
	int clen;

	if (assoc) {
		*outp++ = ASSOCCHAR;
	}
	for (; infn != infnend; ) {
		infn += isochar(infn, infnend, joliet_level, &c, &clen, flags, handle);

		if (!original && !joliet_level && c >= 'A' && c <= 'Z')
			c += ('a' - 'A');
		else if (!original && c == ';') {
			outp -= (d == '.');
			break;
		}
		d = c;
		while(clen--)
			*outp++ = c >> (clen << 3);
	}
	*outfnlen = outp - outfn;
}

/*
 * same as sgetrune(3)
 */
u_short
sgetrune(const char *string, size_t n, char const **result,
	 int flags, void *handle)
{
	size_t i, j, len;
	char outbuf[3], *outp;
	u_short c = '\0';

	len = i = (n < 2) ? n : 2;
	j = 2;
	outp = outbuf;

	if (flags & ISOFSMNT_KICONV && cd9660_iconv) {
		cd9660_iconv->convchr(handle, &string, &i, &outp, &j);
		len -= i;
	} else {
		len = 1;
		string++;
	}

	if (result) *result = string;
	while(len--) c |= (*(string - len - 1) & 0xff) << (len << 3);
	return (c);
}