Linux 2.6.31-rc6
[linux-2.6] / fs / hfsplus / options.c
1 /*
2  *  linux/fs/hfsplus/options.c
3  *
4  * Copyright (C) 2001
5  * Brad Boyer (flar@allandria.com)
6  * (C) 2003 Ardis Technologies <roman@ardistech.com>
7  *
8  * Option parsing
9  */
10
11 #include <linux/string.h>
12 #include <linux/kernel.h>
13 #include <linux/sched.h>
14 #include <linux/parser.h>
15 #include <linux/nls.h>
16 #include <linux/mount.h>
17 #include <linux/seq_file.h>
18 #include "hfsplus_fs.h"
19
20 enum {
21         opt_creator, opt_type,
22         opt_umask, opt_uid, opt_gid,
23         opt_part, opt_session, opt_nls,
24         opt_nodecompose, opt_decompose,
25         opt_force, opt_err
26 };
27
28 static const match_table_t tokens = {
29         { opt_creator, "creator=%s" },
30         { opt_type, "type=%s" },
31         { opt_umask, "umask=%o" },
32         { opt_uid, "uid=%u" },
33         { opt_gid, "gid=%u" },
34         { opt_part, "part=%u" },
35         { opt_session, "session=%u" },
36         { opt_nls, "nls=%s" },
37         { opt_decompose, "decompose" },
38         { opt_nodecompose, "nodecompose" },
39         { opt_force, "force" },
40         { opt_err, NULL }
41 };
42
43 /* Initialize an options object to reasonable defaults */
44 void hfsplus_fill_defaults(struct hfsplus_sb_info *opts)
45 {
46         if (!opts)
47                 return;
48
49         opts->creator = HFSPLUS_DEF_CR_TYPE;
50         opts->type = HFSPLUS_DEF_CR_TYPE;
51         opts->umask = current_umask();
52         opts->uid = current_uid();
53         opts->gid = current_gid();
54         opts->part = -1;
55         opts->session = -1;
56 }
57
58 /* convert a "four byte character" to a 32 bit int with error checks */
59 static inline int match_fourchar(substring_t *arg, u32 *result)
60 {
61         if (arg->to - arg->from != 4)
62                 return -EINVAL;
63         memcpy(result, arg->from, 4);
64         return 0;
65 }
66
67 /* Parse options from mount. Returns 0 on failure */
68 /* input is the options passed to mount() as a string */
69 int hfsplus_parse_options(char *input, struct hfsplus_sb_info *sbi)
70 {
71         char *p;
72         substring_t args[MAX_OPT_ARGS];
73         int tmp, token;
74
75         if (!input)
76                 goto done;
77
78         while ((p = strsep(&input, ",")) != NULL) {
79                 if (!*p)
80                         continue;
81
82                 token = match_token(p, tokens, args);
83                 switch (token) {
84                 case opt_creator:
85                         if (match_fourchar(&args[0], &sbi->creator)) {
86                                 printk(KERN_ERR "hfs: creator requires a 4 character value\n");
87                                 return 0;
88                         }
89                         break;
90                 case opt_type:
91                         if (match_fourchar(&args[0], &sbi->type)) {
92                                 printk(KERN_ERR "hfs: type requires a 4 character value\n");
93                                 return 0;
94                         }
95                         break;
96                 case opt_umask:
97                         if (match_octal(&args[0], &tmp)) {
98                                 printk(KERN_ERR "hfs: umask requires a value\n");
99                                 return 0;
100                         }
101                         sbi->umask = (umode_t)tmp;
102                         break;
103                 case opt_uid:
104                         if (match_int(&args[0], &tmp)) {
105                                 printk(KERN_ERR "hfs: uid requires an argument\n");
106                                 return 0;
107                         }
108                         sbi->uid = (uid_t)tmp;
109                         break;
110                 case opt_gid:
111                         if (match_int(&args[0], &tmp)) {
112                                 printk(KERN_ERR "hfs: gid requires an argument\n");
113                                 return 0;
114                         }
115                         sbi->gid = (gid_t)tmp;
116                         break;
117                 case opt_part:
118                         if (match_int(&args[0], &sbi->part)) {
119                                 printk(KERN_ERR "hfs: part requires an argument\n");
120                                 return 0;
121                         }
122                         break;
123                 case opt_session:
124                         if (match_int(&args[0], &sbi->session)) {
125                                 printk(KERN_ERR "hfs: session requires an argument\n");
126                                 return 0;
127                         }
128                         break;
129                 case opt_nls:
130                         if (sbi->nls) {
131                                 printk(KERN_ERR "hfs: unable to change nls mapping\n");
132                                 return 0;
133                         }
134                         p = match_strdup(&args[0]);
135                         if (p)
136                                 sbi->nls = load_nls(p);
137                         if (!sbi->nls) {
138                                 printk(KERN_ERR "hfs: unable to load nls mapping \"%s\"\n", p);
139                                 kfree(p);
140                                 return 0;
141                         }
142                         kfree(p);
143                         break;
144                 case opt_decompose:
145                         sbi->flags &= ~HFSPLUS_SB_NODECOMPOSE;
146                         break;
147                 case opt_nodecompose:
148                         sbi->flags |= HFSPLUS_SB_NODECOMPOSE;
149                         break;
150                 case opt_force:
151                         sbi->flags |= HFSPLUS_SB_FORCE;
152                         break;
153                 default:
154                         return 0;
155                 }
156         }
157
158 done:
159         if (!sbi->nls) {
160                 /* try utf8 first, as this is the old default behaviour */
161                 sbi->nls = load_nls("utf8");
162                 if (!sbi->nls)
163                         sbi->nls = load_nls_default();
164                 if (!sbi->nls)
165                         return 0;
166         }
167
168         return 1;
169 }
170
171 int hfsplus_show_options(struct seq_file *seq, struct vfsmount *mnt)
172 {
173         struct hfsplus_sb_info *sbi = &HFSPLUS_SB(mnt->mnt_sb);
174
175         if (sbi->creator != HFSPLUS_DEF_CR_TYPE)
176                 seq_printf(seq, ",creator=%.4s", (char *)&sbi->creator);
177         if (sbi->type != HFSPLUS_DEF_CR_TYPE)
178                 seq_printf(seq, ",type=%.4s", (char *)&sbi->type);
179         seq_printf(seq, ",umask=%o,uid=%u,gid=%u", sbi->umask, sbi->uid, sbi->gid);
180         if (sbi->part >= 0)
181                 seq_printf(seq, ",part=%u", sbi->part);
182         if (sbi->session >= 0)
183                 seq_printf(seq, ",session=%u", sbi->session);
184         if (sbi->nls)
185                 seq_printf(seq, ",nls=%s", sbi->nls->charset);
186         if (sbi->flags & HFSPLUS_SB_NODECOMPOSE)
187                 seq_printf(seq, ",nodecompose");
188         return 0;
189 }