release/src-rt-6.x.4708/linux/linux-2.6.36/fs/hfs/trans.c

   1 /*
   2  *  linux/fs/hfs/trans.c
   3  *
   4  * Copyright (C) 1995-1997  Paul H. Hargrove
   5  * This file may be distributed under the terms of the GNU General Public License.
   6  *
   7  * This file contains routines for converting between the Macintosh
   8  * character set and various other encodings.  This includes dealing
   9  * with ':' vs. '/' as the path-element separator.
  10  */
  11
  12 #include <linux/types.h>
  13 #include <linux/nls.h>
  14
  15 #include "hfs_fs.h"
  16
  17 /*================ Global functions ================*/
  18
  19 /*
  20  * hfs_mac2asc()
  21  *
  22  * Given a 'Pascal String' (a string preceded by a length byte) in
  23  * the Macintosh character set produce the corresponding filename using
  24  * the 'trivial' name-mangling scheme, returning the length of the
  25  * mangled filename.  Note that the output string is not NULL
  26  * terminated.
  27  *
  28  * The name-mangling works as follows:
  29  * The character '/', which is illegal in Linux filenames is replaced
  30  * by ':' which never appears in HFS filenames.  All other characters
  31  * are passed unchanged from input to output.
  32  */
  33 int hfs_mac2asc(struct super_block *sb, char *out, const struct hfs_name *in)
  34 {
  35         struct nls_table *nls_disk = HFS_SB(sb)->nls_disk;
  36         struct nls_table *nls_io = HFS_SB(sb)->nls_io;
  37         const char *src;
  38         char *dst;
  39         int srclen, dstlen, size;
  40
  41         src = in->name;
  42         srclen = in->len;
  43         dst = out;
  44         dstlen = HFS_MAX_NAMELEN;
  45         if (nls_io) {
  46                 wchar_t ch;
  47
  48                 while (srclen > 0) {
  49                         if (nls_disk) {
  50                                 size = nls_disk->char2uni(src, srclen, &ch);
  51                                 if (size <= 0) {
  52                                         ch = '?';
  53                                         size = 1;
  54                                 }
  55                                 src += size;
  56                                 srclen -= size;
  57                         } else {
  58                                 ch = *src++;
  59                                 srclen--;
  60                         }
  61                         if (ch == '/')
  62                                 ch = ':';
  63                         size = nls_io->uni2char(ch, dst, dstlen);
  64                         if (size < 0) {
  65                                 if (size == -ENAMETOOLONG)
  66                                         goto out;
  67                                 *dst = '?';
  68                                 size = 1;
  69                         }
  70                         dst += size;
  71                         dstlen -= size;
  72                 }
  73         } else {
  74                 char ch;
  75
  76                 while (--srclen >= 0)
  77                         *dst++ = (ch = *src++) == '/' ? ':' : ch;
  78         }
  79 out:
  80         return dst - out;
  81 }
  82
  83 /*
  84  * hfs_asc2mac()
  85  *
  86  * Given an ASCII string (not null-terminated) and its length,
  87  * generate the corresponding filename in the Macintosh character set
  88  * using the 'trivial' name-mangling scheme, returning the length of
  89  * the mangled filename.  Note that the output string is not NULL
  90  * terminated.
  91  *
  92  * This routine is a inverse to hfs_mac2triv().
  93  * A ':' is replaced by a '/'.
  94  */
  95 void hfs_asc2mac(struct super_block *sb, struct hfs_name *out, struct qstr *in)
  96 {
  97         struct nls_table *nls_disk = HFS_SB(sb)->nls_disk;
  98         struct nls_table *nls_io = HFS_SB(sb)->nls_io;
  99         const char *src;
 100         char *dst;
 101         int srclen, dstlen, size;
 102
 103         src = in->name;
 104         srclen = in->len;
 105         dst = out->name;
 106         dstlen = HFS_NAMELEN;
 107         if (nls_io) {
 108                 wchar_t ch;
 109
 110                 while (srclen > 0) {
 111                         size = nls_io->char2uni(src, srclen, &ch);
 112                         if (size < 0) {
 113                                 ch = '?';
 114                                 size = 1;
 115                         }
 116                         src += size;
 117                         srclen -= size;
 118                         if (ch == ':')
 119                                 ch = '/';
 120                         if (nls_disk) {
 121                                 size = nls_disk->uni2char(ch, dst, dstlen);
 122                                 if (size < 0) {
 123                                         if (size == -ENAMETOOLONG)
 124                                                 goto out;
 125                                         *dst = '?';
 126                                         size = 1;
 127                                 }
 128                                 dst += size;
 129                                 dstlen -= size;
 130                         } else {
 131                                 *dst++ = ch > 0xff ? '?' : ch;
 132                                 dstlen--;
 133                         }
 134                 }
 135         } else {
 136                 char ch;
 137
 138                 if (dstlen > srclen)
 139                         dstlen = srclen;
 140                 while (--dstlen >= 0)
 141                         *dst++ = (ch = *src++) == ':' ? '/' : ch;
 142         }
 143 out:
 144         out->len = dst - (char *)out->name;
 145         dstlen = HFS_NAMELEN - out->len;
 146         while (--dstlen >= 0)
 147                 *dst++ = 0;
 148 }