fs/isofs/joliet.c

   1 /*
   2  *  linux/fs/isofs/joliet.c
   3  *
   4  *  (C) 1996 Gordon Chaffee
   5  *
   6  *  Joliet: Microsoft's Unicode extensions to iso9660
   7  */
   8
   9 #include <linux/string.h>
  10 #include <linux/nls.h>
  11 #include <linux/malloc.h>
  12 #include <linux/iso_fs.h>
  13
  14 /*
  15  * Convert Unicode 16 to UTF8 or ASCII.
  16  */
  17 static int
  18 uni16_to_x8(unsigned char *ascii, u16 *uni, int len, struct nls_table *nls)
  19 {
  20         wchar_t *ip;
  21         unsigned char *op;
  22
  23         ip = uni;
  24         op = ascii;
  25
  26         while (*ip && len) {
  27                 int llen;
  28                 wchar_t ch = be16_to_cpu(*ip);
  29                 if ((llen = nls->uni2char(ch, op, NLS_MAX_CHARSET_SIZE)) > 0)
  30                         op += llen;
  31                 else
  32                         *op++ = '?';
  33                 ip++;
  34
  35                 len--;
  36         }
  37         *op = 0;
  38         return (op - ascii);
  39 }
  40
  41 /* Convert big endian wide character string to utf8 */
  42 static int
  43 wcsntombs_be(__u8 *s, const __u8 *pwcs, int inlen, int maxlen)
  44 {
  45         const __u8 *ip;
  46         __u8 *op;
  47         int size;
  48         __u16 c;
  49
  50         op = s;
  51         ip = pwcs;
  52         while ((*ip || ip[1]) && (maxlen > 0) && (inlen > 0)) {
  53                 c = (*ip << 8) | ip[1];
  54                 if (c > 0x7f) {
  55                         size = utf8_wctomb(op, c, maxlen);
  56                         if (size == -1) {
  57                                 /* Ignore character and move on */
  58                                 maxlen--;
  59                         } else {
  60                                 op += size;
  61                                 maxlen -= size;
  62                         }
  63                 } else {
  64                         *op++ = (__u8) c;
  65                 }
  66                 ip += 2;
  67                 inlen--;
  68         }
  69         return (op - s);
  70 }
  71
  72 int
  73 get_joliet_filename(struct iso_directory_record * de, struct inode * inode,
  74                     unsigned char *outname)
  75 {
  76         unsigned char utf8;
  77         struct nls_table *nls;
  78         unsigned char len = 0;
  79
  80         utf8 = inode->i_sb->u.isofs_sb.s_utf8;
  81         nls = inode->i_sb->u.isofs_sb.s_nls_iocharset;
  82
  83         if (utf8) {
  84                 len = wcsntombs_be(outname, de->name,
  85                                    de->name_len[0] >> 1, PAGE_SIZE);
  86         } else {
  87                 len = uni16_to_x8(outname, (u16 *) de->name,
  88                                   de->name_len[0] >> 1, nls);
  89         }
  90         if ((len > 2) && (outname[len-2] == ';') && (outname[len-1] == '1')) {
  91                 len -= 2;
  92         }
  93
  94         /*
  95          * Windows doesn't like periods at the end of a name,
  96          * so neither do we
  97          */
  98         while (len >= 2 && (outname[len-1] == '.')) {
  99                 len--;
 100         }
 101
 102         return len;
 103 }