xref: /openbmc/linux/fs/hfsplus/options.c (revision 64c70b1c)
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 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->fs->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 			sbi->nls = load_nls(p);
136 			if (!sbi->nls) {
137 				printk(KERN_ERR "hfs: unable to load nls mapping \"%s\"\n", p);
138 				kfree(p);
139 				return 0;
140 			}
141 			kfree(p);
142 			break;
143 		case opt_decompose:
144 			sbi->flags &= ~HFSPLUS_SB_NODECOMPOSE;
145 			break;
146 		case opt_nodecompose:
147 			sbi->flags |= HFSPLUS_SB_NODECOMPOSE;
148 			break;
149 		case opt_force:
150 			sbi->flags |= HFSPLUS_SB_FORCE;
151 			break;
152 		default:
153 			return 0;
154 		}
155 	}
156 
157 done:
158 	if (!sbi->nls) {
159 		/* try utf8 first, as this is the old default behaviour */
160 		sbi->nls = load_nls("utf8");
161 		if (!sbi->nls)
162 			sbi->nls = load_nls_default();
163 		if (!sbi->nls)
164 			return 0;
165 	}
166 
167 	return 1;
168 }
169 
170 int hfsplus_show_options(struct seq_file *seq, struct vfsmount *mnt)
171 {
172 	struct hfsplus_sb_info *sbi = &HFSPLUS_SB(mnt->mnt_sb);
173 
174 	if (sbi->creator != HFSPLUS_DEF_CR_TYPE)
175 		seq_printf(seq, ",creator=%.4s", (char *)&sbi->creator);
176 	if (sbi->type != HFSPLUS_DEF_CR_TYPE)
177 		seq_printf(seq, ",type=%.4s", (char *)&sbi->type);
178 	seq_printf(seq, ",umask=%o,uid=%u,gid=%u", sbi->umask, sbi->uid, sbi->gid);
179 	if (sbi->part >= 0)
180 		seq_printf(seq, ",part=%u", sbi->part);
181 	if (sbi->session >= 0)
182 		seq_printf(seq, ",session=%u", sbi->session);
183 	if (sbi->nls)
184 		seq_printf(seq, ",nls=%s", sbi->nls->charset);
185 	if (sbi->flags & HFSPLUS_SB_NODECOMPOSE)
186 		seq_printf(seq, ",nodecompose");
187 	return 0;
188 }
189