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git.proxmox.com Git - mirror_ubuntu-jammy-kernel.git/blob - lib/parser.c
1 // SPDX-License-Identifier: GPL-2.0-only
3 * lib/parser.c - simple parser for mount, etc. options.
6 #include <linux/ctype.h>
7 #include <linux/types.h>
8 #include <linux/export.h>
9 #include <linux/parser.h>
10 #include <linux/slab.h>
11 #include <linux/string.h>
14 * match_one - Determines if a string matches a simple pattern
15 * @s: the string to examine for presence of the pattern
16 * @p: the string containing the pattern
17 * @args: array of %MAX_OPT_ARGS &substring_t elements. Used to return match
20 * Description: Determines if the pattern @p is present in string @s. Can only
21 * match extremely simple token=arg style patterns. If the pattern is found,
22 * the location(s) of the arguments will be returned in the @args array.
24 static int match_one(char *s
, const char *p
, substring_t args
[])
34 meta
= strchr(p
, '%');
36 return strcmp(p
, s
) == 0;
38 if (strncmp(p
, s
, meta
-p
))
45 len
= simple_strtoul(p
, (char **) &p
, 10);
53 if (argc
>= MAX_OPT_ARGS
)
59 size_t str_len
= strlen(s
);
63 if (len
== -1 || len
> str_len
)
65 args
[argc
].to
= s
+ len
;
69 simple_strtol(s
, &args
[argc
].to
, 0);
72 simple_strtoul(s
, &args
[argc
].to
, 0);
75 simple_strtoul(s
, &args
[argc
].to
, 8);
78 simple_strtoul(s
, &args
[argc
].to
, 16);
80 if (args
[argc
].to
== args
[argc
].from
)
92 * match_token - Find a token (and optional args) in a string
93 * @s: the string to examine for token/argument pairs
94 * @table: match_table_t describing the set of allowed option tokens and the
95 * arguments that may be associated with them. Must be terminated with a
96 * &struct match_token whose pattern is set to the NULL pointer.
97 * @args: array of %MAX_OPT_ARGS &substring_t elements. Used to return match
100 * Description: Detects which if any of a set of token strings has been passed
101 * to it. Tokens can include up to MAX_OPT_ARGS instances of basic c-style
102 * format identifiers which will be taken into account when matching the
103 * tokens, and whose locations will be returned in the @args array.
105 int match_token(char *s
, const match_table_t table
, substring_t args
[])
107 const struct match_token
*p
;
109 for (p
= table
; !match_one(s
, p
->pattern
, args
) ; p
++)
114 EXPORT_SYMBOL(match_token
);
117 * match_number - scan a number in the given base from a substring_t
118 * @s: substring to be scanned
119 * @result: resulting integer on success
120 * @base: base to use when converting string
122 * Description: Given a &substring_t and a base, attempts to parse the substring
123 * as a number in that base. On success, sets @result to the integer represented
124 * by the string and returns 0. Returns -ENOMEM, -EINVAL, or -ERANGE on failure.
126 static int match_number(substring_t
*s
, int *result
, int base
)
133 buf
= match_strdup(s
);
138 val
= simple_strtol(buf
, &endp
, base
);
141 else if (val
< (long)INT_MIN
|| val
> (long)INT_MAX
)
150 * match_u64int - scan a number in the given base from a substring_t
151 * @s: substring to be scanned
152 * @result: resulting u64 on success
153 * @base: base to use when converting string
155 * Description: Given a &substring_t and a base, attempts to parse the substring
156 * as a number in that base. On success, sets @result to the integer represented
157 * by the string and returns 0. Returns -ENOMEM, -EINVAL, or -ERANGE on failure.
159 static int match_u64int(substring_t
*s
, u64
*result
, int base
)
165 buf
= match_strdup(s
);
169 ret
= kstrtoull(buf
, base
, &val
);
177 * match_int - scan a decimal representation of an integer from a substring_t
178 * @s: substring_t to be scanned
179 * @result: resulting integer on success
181 * Description: Attempts to parse the &substring_t @s as a decimal integer. On
182 * success, sets @result to the integer represented by the string and returns 0.
183 * Returns -ENOMEM, -EINVAL, or -ERANGE on failure.
185 int match_int(substring_t
*s
, int *result
)
187 return match_number(s
, result
, 0);
189 EXPORT_SYMBOL(match_int
);
192 * match_uint - scan a decimal representation of an integer from a substring_t
193 * @s: substring_t to be scanned
194 * @result: resulting integer on success
196 * Description: Attempts to parse the &substring_t @s as a decimal integer. On
197 * success, sets @result to the integer represented by the string and returns 0.
198 * Returns -ENOMEM, -EINVAL, or -ERANGE on failure.
200 int match_uint(substring_t
*s
, unsigned int *result
)
203 char *buf
= match_strdup(s
);
206 err
= kstrtouint(buf
, 10, result
);
211 EXPORT_SYMBOL(match_uint
);
214 * match_u64 - scan a decimal representation of a u64 from
216 * @s: substring_t to be scanned
217 * @result: resulting unsigned long long on success
219 * Description: Attempts to parse the &substring_t @s as a long decimal
220 * integer. On success, sets @result to the integer represented by the
221 * string and returns 0.
222 * Returns -ENOMEM, -EINVAL, or -ERANGE on failure.
224 int match_u64(substring_t
*s
, u64
*result
)
226 return match_u64int(s
, result
, 0);
228 EXPORT_SYMBOL(match_u64
);
231 * match_octal - scan an octal representation of an integer from a substring_t
232 * @s: substring_t to be scanned
233 * @result: resulting integer on success
235 * Description: Attempts to parse the &substring_t @s as an octal integer. On
236 * success, sets @result to the integer represented by the string and returns
237 * 0. Returns -ENOMEM, -EINVAL, or -ERANGE on failure.
239 int match_octal(substring_t
*s
, int *result
)
241 return match_number(s
, result
, 8);
243 EXPORT_SYMBOL(match_octal
);
246 * match_hex - scan a hex representation of an integer from a substring_t
247 * @s: substring_t to be scanned
248 * @result: resulting integer on success
250 * Description: Attempts to parse the &substring_t @s as a hexadecimal integer.
251 * On success, sets @result to the integer represented by the string and
252 * returns 0. Returns -ENOMEM, -EINVAL, or -ERANGE on failure.
254 int match_hex(substring_t
*s
, int *result
)
256 return match_number(s
, result
, 16);
258 EXPORT_SYMBOL(match_hex
);
261 * match_wildcard - parse if a string matches given wildcard pattern
262 * @pattern: wildcard pattern
263 * @str: the string to be parsed
265 * Description: Parse the string @str to check if matches wildcard
266 * pattern @pattern. The pattern may contain two type wildcardes:
267 * '*' - matches zero or more characters
268 * '?' - matches one character
269 * If it's matched, return true, else return false.
271 bool match_wildcard(const char *pattern
, const char *str
)
274 const char *p
= pattern
;
309 EXPORT_SYMBOL(match_wildcard
);
312 * match_strlcpy - Copy the characters from a substring_t to a sized buffer
313 * @dest: where to copy to
314 * @src: &substring_t to copy
315 * @size: size of destination buffer
317 * Description: Copy the characters in &substring_t @src to the
318 * c-style string @dest. Copy no more than @size - 1 characters, plus
319 * the terminating NUL. Return length of @src.
321 size_t match_strlcpy(char *dest
, const substring_t
*src
, size_t size
)
323 size_t ret
= src
->to
- src
->from
;
326 size_t len
= ret
>= size
? size
- 1 : ret
;
327 memcpy(dest
, src
->from
, len
);
332 EXPORT_SYMBOL(match_strlcpy
);
335 * match_strdup - allocate a new string with the contents of a substring_t
336 * @s: &substring_t to copy
338 * Description: Allocates and returns a string filled with the contents of
339 * the &substring_t @s. The caller is responsible for freeing the returned
340 * string with kfree().
342 char *match_strdup(const substring_t
*s
)
344 return kmemdup_nul(s
->from
, s
->to
- s
->from
, GFP_KERNEL
);
346 EXPORT_SYMBOL(match_strdup
);