/*
   *   Copyright (C) International Business Machines Corp., 2000-2004
   *
   *   This program is free software;  you can redistribute it and/or modify
   *   it under the terms of the GNU General Public License as published by
   *   the Free Software Foundation; either version 2 of the License, or
   *   (at your option) any later version.
   *
   *   This program 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 General Public License for more details.
   *
   *   You should have received a copy of the GNU General Public License
   *   along with this program;  if not, write to the Free Software
   *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
   */
  
  #include <linux/fs.h>
  #include <linux/slab.h>
  #include "jfs_incore.h"
  #include "jfs_filsys.h"
  #include "jfs_unicode.h"
  #include "jfs_debug.h"
  
  /*
   * NAME:	jfs_strfromUCS()
   *
   * FUNCTION:	Convert little-endian unicode string to character string
   *
   */
  int jfs_strfromUCS_le(char *to, const __le16 * from,
  		      int len, struct nls_table *codepage)
  {
  	int i;
  	int outlen = 0;
  	static int warn_again = 5;	/* Only warn up to 5 times total */
  	int warn = !!warn_again;	/* once per string */
  
  	if (codepage) {
  		for (i = 0; (i < len) && from[i]; i++) {
  			int charlen;
  			charlen =
  			    codepage->uni2char(le16_to_cpu(from[i]),
  					       &to[outlen],
  					       NLS_MAX_CHARSET_SIZE);
  			if (charlen > 0)
  				outlen += charlen;
  			else
  				to[outlen++] = '?';
  		}
  	} else {
  		for (i = 0; (i < len) && from[i]; i++) {
  			if (unlikely(le16_to_cpu(from[i]) & 0xff00)) {
  				to[i] = '?';
  				if (unlikely(warn)) {
  					warn--;
  					warn_again--;
  					printk(KERN_ERR
  			"non-latin1 character 0x%x found in JFS file name
  ",
  					       le16_to_cpu(from[i]));
  					printk(KERN_ERR
  				"mount with iocharset=utf8 to access
  ");
  				}
  
  			}
  			else
  				to[i] = (char) (le16_to_cpu(from[i]));
  		}
  		outlen = i;
  	}
  	to[outlen] = 0;
  	return outlen;
  }
  
  /*
   * NAME:	jfs_strtoUCS()
   *
   * FUNCTION:	Convert character string to unicode string
   *
   */
  static int jfs_strtoUCS(wchar_t * to, const unsigned char *from, int len,
  		struct nls_table *codepage)
  {
  	int charlen;
  	int i;
  
  	if (codepage) {
  		for (i = 0; len && *from; i++, from += charlen, len -= charlen)
  		{
  			charlen = codepage->char2uni(from, len, &to[i]);
  			if (charlen < 1) {
  				jfs_err("jfs_strtoUCS: char2uni returned %d.",
  					charlen);
  				jfs_err("charset = %s, char = 0x%x",
  					codepage->charset, *from);
  				return charlen;
  			}
  		}
  	} else {
  		for (i = 0; (i < len) && from[i]; i++)
  			to[i] = (wchar_t) from[i];
  	}
  
  	to[i] = 0;
  	return i;
  }
  
  /*
   * NAME:	get_UCSname()
   *
   * FUNCTION:	Allocate and translate to unicode string
   *
   */
  int get_UCSname(struct component_name * uniName, struct dentry *dentry)
  {
  	struct nls_table *nls_tab = JFS_SBI(dentry->d_sb)->nls_tab;
  	int length = dentry->d_name.len;
  
  	if (length > JFS_NAME_MAX)
  		return -ENAMETOOLONG;
  
  	uniName->name =
  	    kmalloc((length + 1) * sizeof(wchar_t), GFP_NOFS);
  
  	if (uniName->name == NULL)
  		return -ENOMEM;
  
  	uniName->namlen = jfs_strtoUCS(uniName->name, dentry->d_name.name,
  				       length, nls_tab);
  
  	if (uniName->namlen < 0) {
  		kfree(uniName->name);
  		return uniName->namlen;
  	}
  
  	return 0;
  }