1/*
2 *  linux/fs/hpfs/name.c
3 *
4 *  Mikulas Patocka (mikulas@artax.karlin.mff.cuni.cz), 1998-1999
5 *
6 *  operations with filenames
7 */
8
9#include "hpfs_fn.h"
10
11static inline int not_allowed_char(unsigned char c)
12{
13	return c<' ' || c=='"' || c=='*' || c=='/' || c==':' || c=='<' ||
14	      c=='>' || c=='?' || c=='\\' || c=='|';
15}
16
17static inline int no_dos_char(unsigned char c)
18{	/* Characters that are allowed in HPFS but not in DOS */
19	return c=='+' || c==',' || c==';' || c=='=' || c=='[' || c==']';
20}
21
22static inline unsigned char upcase(unsigned char *dir, unsigned char a)
23{
24	if (a<128 || a==255) return a>='a' && a<='z' ? a - 0x20 : a;
25	if (!dir) return a;
26	return dir[a-128];
27}
28
29unsigned char hpfs_upcase(unsigned char *dir, unsigned char a)
30{
31	return upcase(dir, a);
32}
33
34static inline unsigned char locase(unsigned char *dir, unsigned char a)
35{
36	if (a<128 || a==255) return a>='A' && a<='Z' ? a + 0x20 : a;
37	if (!dir) return a;
38	return dir[a];
39}
40
41int hpfs_chk_name(const unsigned char *name, unsigned *len)
42{
43	int i;
44	if (*len > 254) return -ENAMETOOLONG;
45	hpfs_adjust_length(name, len);
46	if (!*len) return -EINVAL;
47	for (i = 0; i < *len; i++) if (not_allowed_char(name[i])) return -EINVAL;
48	if (*len == 1) if (name[0] == '.') return -EINVAL;
49	if (*len == 2) if (name[0] == '.' && name[1] == '.') return -EINVAL;
50	return 0;
51}
52
53unsigned char *hpfs_translate_name(struct super_block *s, unsigned char *from,
54			  unsigned len, int lc, int lng)
55{
56	unsigned char *to;
57	int i;
58	if (hpfs_sb(s)->sb_chk >= 2) if (hpfs_is_name_long(from, len) != lng) {
59		pr_err("Long name flag mismatch - name ");
60		for (i = 0; i < len; i++)
61			pr_cont("%c", from[i]);
62		pr_cont(" misidentified as %s.\n", lng ? "short" : "long");
63		pr_err("It's nothing serious. It could happen because of bug in OS/2.\nSet checks=normal to disable this message.\n");
64	}
65	if (!lc) return from;
66	if (!(to = kmalloc(len, GFP_KERNEL))) {
67		pr_err("can't allocate memory for name conversion buffer\n");
68		return from;
69	}
70	for (i = 0; i < len; i++) to[i] = locase(hpfs_sb(s)->sb_cp_table,from[i]);
71	return to;
72}
73
74int hpfs_compare_names(struct super_block *s,
75		       const unsigned char *n1, unsigned l1,
76		       const unsigned char *n2, unsigned l2, int last)
77{
78	unsigned l = l1 < l2 ? l1 : l2;
79	unsigned i;
80	if (last) return -1;
81	for (i = 0; i < l; i++) {
82		unsigned char c1 = upcase(hpfs_sb(s)->sb_cp_table,n1[i]);
83		unsigned char c2 = upcase(hpfs_sb(s)->sb_cp_table,n2[i]);
84		if (c1 < c2) return -1;
85		if (c1 > c2) return 1;
86	}
87	if (l1 < l2) return -1;
88	if (l1 > l2) return 1;
89	return 0;
90}
91
92int hpfs_is_name_long(const unsigned char *name, unsigned len)
93{
94	int i,j;
95	for (i = 0; i < len && name[i] != '.'; i++)
96		if (no_dos_char(name[i])) return 1;
97	if (!i || i > 8) return 1;
98	if (i == len) return 0;
99	for (j = i + 1; j < len; j++)
100		if (name[j] == '.' || no_dos_char(name[i])) return 1;
101	return j - i > 4;
102}
103
104/* OS/2 clears dots and spaces at the end of file name, so we have to */
105
106void hpfs_adjust_length(const unsigned char *name, unsigned *len)
107{
108	if (!*len) return;
109	if (*len == 1 && name[0] == '.') return;
110	if (*len == 2 && name[0] == '.' && name[1] == '.') return;
111	while (*len && (name[*len - 1] == '.' || name[*len - 1] == ' '))
112		(*len)--;
113}
114