Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * getopt.c
4 */
5
6#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
7
8#include <linux/kernel.h>
9#include <linux/string.h>
10
11#include <asm/errno.h>
12
13#include "getopt.h"
14
15/**
16 * ncp_getopt - option parser
17 * @caller: name of the caller, for error messages
18 * @options: the options string
19 * @opts: an array of &struct option entries controlling parser operations
20 * @optopt: output; will contain the current option
21 * @optarg: output; will contain the value (if one exists)
22 * @value: output; may be NULL; will be overwritten with the integer value
23 * of the current argument.
24 *
25 * Helper to parse options on the format used by mount ("a=b,c=d,e,f").
26 * Returns opts->val if a matching entry in the 'opts' array is found,
27 * 0 when no more tokens are found, -1 if an error is encountered.
28 */
29int ncp_getopt(const char *caller, char **options, const struct ncp_option *opts,
30 char **optopt, char **optarg, unsigned long *value)
31{
32 char *token;
33 char *val;
34
35 do {
36 if ((token = strsep(options, ",")) == NULL)
37 return 0;
38 } while (*token == '\0');
39 if (optopt)
40 *optopt = token;
41
42 if ((val = strchr (token, '=')) != NULL) {
43 *val++ = 0;
44 }
45 *optarg = val;
46 for (; opts->name; opts++) {
47 if (!strcmp(opts->name, token)) {
48 if (!val) {
49 if (opts->has_arg & OPT_NOPARAM) {
50 return opts->val;
51 }
52 pr_info("%s: the %s option requires an argument\n",
53 caller, token);
54 return -EINVAL;
55 }
56 if (opts->has_arg & OPT_INT) {
57 int rc = kstrtoul(val, 0, value);
58
59 if (rc) {
60 pr_info("%s: invalid numeric value in %s=%s\n",
61 caller, token, val);
62 return rc;
63 }
64 return opts->val;
65 }
66 if (opts->has_arg & OPT_STRING) {
67 return opts->val;
68 }
69 pr_info("%s: unexpected argument %s to the %s option\n",
70 caller, val, token);
71 return -EINVAL;
72 }
73 }
74 pr_info("%s: Unrecognized mount option %s\n", caller, token);
75 return -EOPNOTSUPP;
76}