LXR linux/fs/ncpfs/getopt.c

   1/*
   2 * getopt.c
   3 */
   4
   5#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
   6
   7#include <linux/kernel.h>
   8#include <linux/string.h>
   9
  10#include <asm/errno.h>
  11
  12#include "getopt.h"
  13
  14/**
  15 *      ncp_getopt - option parser
  16 *      @caller: name of the caller, for error messages
  17 *      @options: the options string
  18 *      @opts: an array of &struct option entries controlling parser operations
  19 *      @optopt: output; will contain the current option
  20 *      @optarg: output; will contain the value (if one exists)
  21 *      @value: output; may be NULL; will be overwritten with the integer value
  22 *              of the current argument.
  23 *
  24 *      Helper to parse options on the format used by mount ("a=b,c=d,e,f").
  25 *      Returns opts->val if a matching entry in the 'opts' array is found,
  26 *      0 when no more tokens are found, -1 if an error is encountered.
  27 */
  28int ncp_getopt(const char *caller, char **options, const struct ncp_option *opts,
  29               char **optopt, char **optarg, unsigned long *value)
  30{
  31        char *token;
  32        char *val;
  33
  34        do {
  35                if ((token = strsep(options, ",")) == NULL)
  36                        return 0;
  37        } while (*token == '\0');
  38        if (optopt)
  39                *optopt = token;
  40
  41        if ((val = strchr (token, '=')) != NULL) {
  42                *val++ = 0;
  43        }
  44        *optarg = val;
  45        for (; opts->name; opts++) {
  46                if (!strcmp(opts->name, token)) {
  47                        if (!val) {
  48                                if (opts->has_arg & OPT_NOPARAM) {
  49                                        return opts->val;
  50                                }
  51                                pr_info("%s: the %s option requires an argument\n",
  52                                        caller, token);
  53                                return -EINVAL;
  54                        }
  55                        if (opts->has_arg & OPT_INT) {
  56                                int rc = kstrtoul(val, 0, value);
  57
  58                                if (rc) {
  59                                        pr_info("%s: invalid numeric value in %s=%s\n",
  60                                                caller, token, val);
  61                                        return rc;
  62                                }
  63                                return opts->val;
  64                        }
  65                        if (opts->has_arg & OPT_STRING) {
  66                                return opts->val;
  67                        }
  68                        pr_info("%s: unexpected argument %s to the %s option\n",
  69                                caller, val, token);
  70                        return -EINVAL;
  71                }
  72        }
  73        pr_info("%s: Unrecognized mount option %s\n", caller, token);
  74        return -EOPNOTSUPP;
  75}
  76