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 "hfsplus_fs.h"
  15
  16 /* Initialize an options object to reasonable defaults */
  17 void fill_defaults(struct hfsplus_sb_info *opts)
  18 {
  19         if (!opts)
  20                 return;
  21
  22         opts->creator = HFSPLUS_DEF_CR_TYPE;
  23         opts->type = HFSPLUS_DEF_CR_TYPE;
  24         opts->umask = current->fs->umask;
  25         opts->uid = current->uid;
  26         opts->gid = current->gid;
  27         opts->part = -1;
  28         opts->session = -1;
  29 }
  30
  31 /* convert a "four byte character" to a 32 bit int with error checks */
  32 static int fill_fourchar(u32 *result, char *input)
  33 {
  34         u32 out;
  35         int i;
  36
  37         if (!result || !input || !*input || (strlen(input) != 4))
  38                 return 0;
  39
  40         for (out = 0, i = 0; i < 4; i++) {
  41                 out <<= 8;
  42                 out |= ((int)(input[i])) & 0xFF;
  43         }
  44         *result = out;
  45         return 1;
  46 }
  47
  48 /* convert a string to int with error checks */
  49 static int fill_int(int *result, char *input, int base)
  50 {
  51         char *tmp = input;
  52         int intval;
  53
  54         if (!result || !input || !*input)
  55                 return 0;
  56
  57         intval = simple_strtoul(tmp, &tmp, base);
  58         if (*tmp)
  59                 return 0;
  60
  61         *result = intval;
  62         return 1;
  63 }
  64
  65 /* Parse options from mount. Returns 0 on failure */
  66 /* input is the options passed to mount() as a string */
  67 int parse_options(char *input, struct hfsplus_sb_info *results)
  68 {
  69         char *curropt, *value;
  70         int tmp;
  71
  72         if (!input)
  73                 return 1;
  74
  75         while ((curropt = strsep(&input,",")) != NULL) {
  76                 if (!*curropt)
  77                         continue;
  78
  79                 if ((value = strchr(curropt, '=')) != NULL)
  80                         *value++ = '\0';
  81
  82                 if (!strcmp(curropt, "creator")) {
  83                         if (!fill_fourchar(&(results->creator), value)) {
  84                                 printk("HFS+-fs: creator requires a 4 character value\n");
  85                                 return 0;
  86                         }
  87                 } else if (!strcmp(curropt, "type")) {
  88                         if (!fill_fourchar(&(results->type), value)) {
  89                                 printk("HFS+-fs: type requires a 4 character value\n");
  90                                 return 0;
  91                         }
  92                 } else if (!strcmp(curropt, "umask")) {
  93                         if (!fill_int(&tmp, value, 8)) {
  94                                 printk("HFS+-fs: umask requires a value\n");
  95                                 return 0;
  96                         }
  97                         results->umask = (umode_t)tmp;
  98                 } else if (!strcmp(curropt, "uid")) {
  99                         if (!fill_int(&tmp, value, 0)) {
 100                                 printk("HFS+-fs: uid requires an argument\n");
 101                                 return 0;
 102                         }
 103                         results->uid = (uid_t)tmp;
 104                 } else if (!strcmp(curropt, "gid")) {
 105                         if (!fill_int(&tmp, value, 0)) {
 106                                 printk("HFS+-fs: gid requires an argument\n");
 107                                 return 0;
 108                         }
 109                         results->gid = (gid_t)tmp;
 110                 } else if (!strcmp(curropt, "part")) {
 111                         if (!fill_int(&results->part, value, 0)) {
 112                                 printk("HFS+-fs: part requires an argument\n");
 113                                 return 0;
 114                         }
 115                 } else if (!strcmp(curropt, "session")) {
 116                         if (!fill_int(&results->session, value, 0)) {
 117                                 printk("HFS+-fs: session requires an argument\n");
 118                                 return 0;
 119                         }
 120                 } else {
 121                         printk("HFS+-fs: unknown option %s\n", curropt);
 122                         return 0;
 123                 }
 124         }
 125
 126         return 1;
 127 }