xref: /linux/fs/hfsplus/options.c (revision 2624f124b3b5d550ab2fbef7ee3bc0e1fed09722)
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_err
26 };
27 
28 static 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_err, NULL }
40 };
41 
42 /* Initialize an options object to reasonable defaults */
43 void hfsplus_fill_defaults(struct hfsplus_sb_info *opts)
44 {
45 	if (!opts)
46 		return;
47 
48 	opts->creator = HFSPLUS_DEF_CR_TYPE;
49 	opts->type = HFSPLUS_DEF_CR_TYPE;
50 	opts->umask = current->fs->umask;
51 	opts->uid = current->uid;
52 	opts->gid = current->gid;
53 	opts->part = -1;
54 	opts->session = -1;
55 }
56 
57 /* convert a "four byte character" to a 32 bit int with error checks */
58 static inline int match_fourchar(substring_t *arg, u32 *result)
59 {
60 	if (arg->to - arg->from != 4)
61 		return -EINVAL;
62 	memcpy(result, arg->from, 4);
63 	return 0;
64 }
65 
66 /* Parse options from mount. Returns 0 on failure */
67 /* input is the options passed to mount() as a string */
68 int hfsplus_parse_options(char *input, struct hfsplus_sb_info *sbi)
69 {
70 	char *p;
71 	substring_t args[MAX_OPT_ARGS];
72 	int tmp, token;
73 
74 	if (!input)
75 		goto done;
76 
77 	while ((p = strsep(&input, ",")) != NULL) {
78 		if (!*p)
79 			continue;
80 
81 		token = match_token(p, tokens, args);
82 		switch (token) {
83 		case opt_creator:
84 			if (match_fourchar(&args[0], &sbi->creator)) {
85 				printk("HFS+-fs: creator requires a 4 character value\n");
86 				return 0;
87 			}
88 			break;
89 		case opt_type:
90 			if (match_fourchar(&args[0], &sbi->type)) {
91 				printk("HFS+-fs: type requires a 4 character value\n");
92 				return 0;
93 			}
94 			break;
95 		case opt_umask:
96 			if (match_octal(&args[0], &tmp)) {
97 				printk("HFS+-fs: umask requires a value\n");
98 				return 0;
99 			}
100 			sbi->umask = (umode_t)tmp;
101 			break;
102 		case opt_uid:
103 			if (match_int(&args[0], &tmp)) {
104 				printk("HFS+-fs: uid requires an argument\n");
105 				return 0;
106 			}
107 			sbi->uid = (uid_t)tmp;
108 			break;
109 		case opt_gid:
110 			if (match_int(&args[0], &tmp)) {
111 				printk("HFS+-fs: gid requires an argument\n");
112 				return 0;
113 			}
114 			sbi->gid = (gid_t)tmp;
115 			break;
116 		case opt_part:
117 			if (match_int(&args[0], &sbi->part)) {
118 				printk("HFS+-fs: part requires an argument\n");
119 				return 0;
120 			}
121 			break;
122 		case opt_session:
123 			if (match_int(&args[0], &sbi->session)) {
124 				printk("HFS+-fs: session requires an argument\n");
125 				return 0;
126 			}
127 			break;
128 		case opt_nls:
129 			if (sbi->nls) {
130 				printk("HFS+-fs: unable to change nls mapping\n");
131 				return 0;
132 			}
133 			p = match_strdup(&args[0]);
134 			sbi->nls = load_nls(p);
135 			if (!sbi->nls) {
136 				printk("HFS+-fs: unable to load nls mapping \"%s\"\n", p);
137 				kfree(p);
138 				return 0;
139 			}
140 			kfree(p);
141 			break;
142 		case opt_decompose:
143 			sbi->flags &= ~HFSPLUS_SB_NODECOMPOSE;
144 			break;
145 		case opt_nodecompose:
146 			sbi->flags |= HFSPLUS_SB_NODECOMPOSE;
147 			break;
148 		default:
149 			return 0;
150 		}
151 	}
152 
153 done:
154 	if (!sbi->nls) {
155 		/* try utf8 first, as this is the old default behaviour */
156 		sbi->nls = load_nls("utf8");
157 		if (!sbi->nls)
158 			sbi->nls = load_nls_default();
159 		if (!sbi->nls)
160 			return 0;
161 	}
162 
163 	return 1;
164 }
165 
166 int hfsplus_show_options(struct seq_file *seq, struct vfsmount *mnt)
167 {
168 	struct hfsplus_sb_info *sbi = &HFSPLUS_SB(mnt->mnt_sb);
169 
170 	if (sbi->creator != HFSPLUS_DEF_CR_TYPE)
171 		seq_printf(seq, ",creator=%.4s", (char *)&sbi->creator);
172 	if (sbi->type != HFSPLUS_DEF_CR_TYPE)
173 		seq_printf(seq, ",type=%.4s", (char *)&sbi->type);
174 	seq_printf(seq, ",umask=%o,uid=%u,gid=%u", sbi->umask, sbi->uid, sbi->gid);
175 	if (sbi->part >= 0)
176 		seq_printf(seq, ",part=%u", sbi->part);
177 	if (sbi->session >= 0)
178 		seq_printf(seq, ",session=%u", sbi->session);
179 	if (sbi->nls)
180 		seq_printf(seq, ",nls=%s", sbi->nls->charset);
181 	if (sbi->flags & HFSPLUS_SB_NODECOMPOSE)
182 		seq_printf(seq, ",nodecompose");
183 	return 0;
184 }
185