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 
not_allowed_char(unsigned char c)11 static inline int not_allowed_char(unsigned char c)
12 {
13 	return c<' ' || c=='"' || c=='*' || c=='/' || c==':' || c=='<' ||
14 	      c=='>' || c=='?' || c=='\\' || c=='|';
15 }
16 
no_dos_char(unsigned char c)17 static 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 
upcase(unsigned char * dir,unsigned char a)22 static 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 
hpfs_upcase(unsigned char * dir,unsigned char a)29 unsigned char hpfs_upcase(unsigned char *dir, unsigned char a)
30 {
31 	return upcase(dir, a);
32 }
33 
locase(unsigned char * dir,unsigned char a)34 static 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 
hpfs_chk_name(const unsigned char * name,unsigned * len)41 int 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 
hpfs_translate_name(struct super_block * s,unsigned char * from,unsigned len,int lc,int lng)53 unsigned 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 		printk("HPFS: Long name flag mismatch - name ");
60 		for (i=0; i<len; i++) printk("%c", from[i]);
61 		printk(" misidentified as %s.\n", lng ? "short" : "long");
62 		printk("HPFS: It's nothing serious. It could happen because of bug in OS/2.\nHPFS: Set checks=normal to disable this message.\n");
63 	}
64 	if (!lc) return from;
65 	if (!(to = kmalloc(len, GFP_KERNEL))) {
66 		printk("HPFS: can't allocate memory for name conversion buffer\n");
67 		return from;
68 	}
69 	for (i = 0; i < len; i++) to[i] = locase(hpfs_sb(s)->sb_cp_table,from[i]);
70 	return to;
71 }
72 
hpfs_compare_names(struct super_block * s,const unsigned char * n1,unsigned l1,const unsigned char * n2,unsigned l2,int last)73 int hpfs_compare_names(struct super_block *s,
74 		       const unsigned char *n1, unsigned l1,
75 		       const unsigned char *n2, unsigned l2, int last)
76 {
77 	unsigned l = l1 < l2 ? l1 : l2;
78 	unsigned i;
79 	if (last) return -1;
80 	for (i = 0; i < l; i++) {
81 		unsigned char c1 = upcase(hpfs_sb(s)->sb_cp_table,n1[i]);
82 		unsigned char c2 = upcase(hpfs_sb(s)->sb_cp_table,n2[i]);
83 		if (c1 < c2) return -1;
84 		if (c1 > c2) return 1;
85 	}
86 	if (l1 < l2) return -1;
87 	if (l1 > l2) return 1;
88 	return 0;
89 }
90 
hpfs_is_name_long(const unsigned char * name,unsigned len)91 int hpfs_is_name_long(const unsigned char *name, unsigned len)
92 {
93 	int i,j;
94 	for (i = 0; i < len && name[i] != '.'; i++)
95 		if (no_dos_char(name[i])) return 1;
96 	if (!i || i > 8) return 1;
97 	if (i == len) return 0;
98 	for (j = i + 1; j < len; j++)
99 		if (name[j] == '.' || no_dos_char(name[i])) return 1;
100 	return j - i > 4;
101 }
102 
103 /* OS/2 clears dots and spaces at the end of file name, so we have to */
104 
hpfs_adjust_length(const unsigned char * name,unsigned * len)105 void hpfs_adjust_length(const unsigned char *name, unsigned *len)
106 {
107 	if (!*len) return;
108 	if (*len == 1 && name[0] == '.') return;
109 	if (*len == 2 && name[0] == '.' && name[1] == '.') return;
110 	while (*len && (name[*len - 1] == '.' || name[*len - 1] == ' '))
111 		(*len)--;
112 }
113