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_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 }