fs/ncpfs/getopt.c

   1 /*
   2  * getopt.c
   3  */
   4
   5 #include <linux/kernel.h>
   6 #include <linux/string.h>
   7
   8 #include <asm/errno.h>
   9
  10 #include "getopt.h"
  11
  12 /**
  13  *      ncp_getopt - option parser
  14  *      @caller: name of the caller, for error messages
  15  *      @options: the options string
  16  *      @opts: an array of &struct option entries controlling parser operations
  17  *      @optopt: output; will contain the current option
  18  *      @optarg: output; will contain the value (if one exists)
  19  *      @flag: output; may be NULL; should point to a long for or'ing flags
  20  *      @value: output; may be NULL; will be overwritten with the integer value
  21  *              of the current argument.
  22  *
  23  *      Helper to parse options on the format used by mount ("a=b,c=d,e,f").
  24  *      Returns opts->val if a matching entry in the 'opts' array is found,
  25  *      0 when no more tokens are found, -1 if an error is encountered.
  26  */
  27 int ncp_getopt(const char *caller, char **options, const struct ncp_option *opts,
  28                char **optopt, char **optarg, unsigned long *value)
  29 {
  30         char *token;
  31         char *val;
  32
  33         do {
  34                 if ((token = strsep(options, ",")) == NULL)
  35                         return 0;
  36         } while (*token == '\0');
  37         if (optopt)
  38                 *optopt = token;
  39
  40         if ((val = strchr (token, '=')) != NULL) {
  41                 *val++ = 0;
  42         }
  43         *optarg = val;
  44         for (; opts->name; opts++) {
  45                 if (!strcmp(opts->name, token)) {
  46                         if (!val) {
  47                                 if (opts->has_arg & OPT_NOPARAM) {
  48                                         return opts->val;
  49                                 }
  50                                 printk(KERN_INFO "%s: the %s option requires an argument\n",
  51                                        caller, token);
  52                                 return -EINVAL;
  53                         }
  54                         if (opts->has_arg & OPT_INT) {
  55                                 char* v;
  56
  57                                 *value = simple_strtoul(val, &v, 0);
  58                                 if (!*v) {
  59                                         return opts->val;
  60                                 }
  61                                 printk(KERN_INFO "%s: invalid numeric value in %s=%s\n",
  62                                         caller, token, val);
  63                                 return -EDOM;
  64                         }
  65                         if (opts->has_arg & OPT_STRING) {
  66                                 return opts->val;
  67                         }
  68                         printk(KERN_INFO "%s: unexpected argument %s to the %s option\n",
  69                                 caller, val, token);
  70                         return -EINVAL;
  71                 }
  72         }
  73         printk(KERN_INFO "%s: Unrecognized mount option %s\n", caller, token);
  74         return -EOPNOTSUPP;
  75 }