fs/isofs/joliet.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  *  linux/fs/isofs/joliet.c
   4  *
   5  *  (C) 1996 Gordon Chaffee
   6  *
   7  *  Joliet: Microsoft's Unicode extensions to iso9660
   8  */
   9
  10 #include <linux/types.h>
  11 #include <linux/nls.h>
  12 #include "isofs.h"
  13
  14 /*
  15  * Convert Unicode 16 to UTF-8 or ASCII.
  16  */
  17 static int
  18 uni16_to_x8(unsigned char *ascii, __be16 *uni, int len, struct nls_table *nls)
  19 {
  20         __be16 *ip, ch;
  21         unsigned char *op;
  22
  23         ip = uni;
  24         op = ascii;
  25
  26         while ((ch = get_unaligned(ip)) && len) {
  27                 int llen;
  28                 llen = nls->uni2char(be16_to_cpu(ch), op, NLS_MAX_CHARSET_SIZE);
  29                 if (llen > 0)
  30                         op += llen;
  31                 else
  32                         *op++ = '?';
  33                 ip++;
  34
  35                 len--;
  36         }
  37         *op = 0;
  38         return (op - ascii);
  39 }
  40
  41 int
  42 get_joliet_filename(struct iso_directory_record * de, unsigned char *outname, struct inode * inode)
  43 {
  44         unsigned char utf8;
  45         struct nls_table *nls;
  46         unsigned char len = 0;
  47
  48         utf8 = ISOFS_SB(inode->i_sb)->s_utf8;
  49         nls = ISOFS_SB(inode->i_sb)->s_nls_iocharset;
  50
  51         if (utf8) {
  52                 len = utf16s_to_utf8s((const wchar_t *) de->name,
  53                                 de->name_len[0] >> 1, UTF16_BIG_ENDIAN,
  54                                 outname, PAGE_SIZE);
  55         } else {
  56                 len = uni16_to_x8(outname, (__be16 *) de->name,
  57                                 de->name_len[0] >> 1, nls);
  58         }
  59         if ((len > 2) && (outname[len-2] == ';') && (outname[len-1] == '1'))
  60                 len -= 2;
  61
  62         /*
  63          * Windows doesn't like periods at the end of a name,
  64          * so neither do we
  65          */
  66         while (len >= 2 && (outname[len-1] == '.'))
  67                 len--;
  68
  69         return len;
  70 }