xref: /openbmc/linux/fs/isofs/joliet.c (revision 0545810f)
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 	struct nls_table *nls;
45 	unsigned char len = 0;
46 
47 	nls = ISOFS_SB(inode->i_sb)->s_nls_iocharset;
48 
49 	if (!nls) {
50 		len = utf16s_to_utf8s((const wchar_t *) de->name,
51 				de->name_len[0] >> 1, UTF16_BIG_ENDIAN,
52 				outname, PAGE_SIZE);
53 	} else {
54 		len = uni16_to_x8(outname, (__be16 *) de->name,
55 				de->name_len[0] >> 1, nls);
56 	}
57 	if ((len > 2) && (outname[len-2] == ';') && (outname[len-1] == '1'))
58 		len -= 2;
59 
60 	/*
61 	 * Windows doesn't like periods at the end of a name,
62 	 * so neither do we
63 	 */
64 	while (len >= 2 && (outname[len-1] == '.'))
65 		len--;
66 
67 	return len;
68 }
69