// SPDX-License-Identifier: GPL-2.0-only /* * lib/parser.c - simple parser for mount, etc. options. */ #include <linux/ctype.h> #include <linux/types.h> #include <linux/export.h> #include <linux/kstrtox.h> #include <linux/parser.h> #include <linux/slab.h> #include <linux/string.h> /* * max size needed by different bases to express U64 * HEX: "0xFFFFFFFFFFFFFFFF" --> 18 * DEC: "18446744073709551615" --> 20 * OCT: "01777777777777777777777" --> 23 * pick the max one to define NUMBER_BUF_LEN */ #define NUMBER_BUF_LEN … /** * match_one - Determines if a string matches a simple pattern * @s: the string to examine for presence of the pattern * @p: the string containing the pattern * @args: array of %MAX_OPT_ARGS &substring_t elements. Used to return match * locations. * * Description: Determines if the pattern @p is present in string @s. Can only * match extremely simple token=arg style patterns. If the pattern is found, * the location(s) of the arguments will be returned in the @args array. */ static int match_one(char *s, const char *p, substring_t args[]) { … } /** * match_token - Find a token (and optional args) in a string * @s: the string to examine for token/argument pairs * @table: match_table_t describing the set of allowed option tokens and the * arguments that may be associated with them. Must be terminated with a * &struct match_token whose pattern is set to the NULL pointer. * @args: array of %MAX_OPT_ARGS &substring_t elements. Used to return match * locations. * * Description: Detects which if any of a set of token strings has been passed * to it. Tokens can include up to %MAX_OPT_ARGS instances of basic c-style * format identifiers which will be taken into account when matching the * tokens, and whose locations will be returned in the @args array. */ int match_token(char *s, const match_table_t table, substring_t args[]) { … } EXPORT_SYMBOL(…); /** * match_number - scan a number in the given base from a substring_t * @s: substring to be scanned * @result: resulting integer on success * @base: base to use when converting string * * Description: Given a &substring_t and a base, attempts to parse the substring * as a number in that base. * * Return: On success, sets @result to the integer represented by the * string and returns 0. Returns -EINVAL or -ERANGE on failure. */ static int match_number(substring_t *s, int *result, int base) { … } /** * match_u64int - scan a number in the given base from a substring_t * @s: substring to be scanned * @result: resulting u64 on success * @base: base to use when converting string * * Description: Given a &substring_t and a base, attempts to parse the substring * as a number in that base. * * Return: On success, sets @result to the integer represented by the * string and returns 0. Returns -EINVAL or -ERANGE on failure. */ static int match_u64int(substring_t *s, u64 *result, int base) { … } /** * match_int - scan a decimal representation of an integer from a substring_t * @s: substring_t to be scanned * @result: resulting integer on success * * Description: Attempts to parse the &substring_t @s as a decimal integer. * * Return: On success, sets @result to the integer represented by the string * and returns 0. Returns -EINVAL or -ERANGE on failure. */ int match_int(substring_t *s, int *result) { … } EXPORT_SYMBOL(…); /** * match_uint - scan a decimal representation of an integer from a substring_t * @s: substring_t to be scanned * @result: resulting integer on success * * Description: Attempts to parse the &substring_t @s as a decimal integer. * * Return: On success, sets @result to the integer represented by the string * and returns 0. Returns -EINVAL or -ERANGE on failure. */ int match_uint(substring_t *s, unsigned int *result) { … } EXPORT_SYMBOL(…); /** * match_u64 - scan a decimal representation of a u64 from * a substring_t * @s: substring_t to be scanned * @result: resulting unsigned long long on success * * Description: Attempts to parse the &substring_t @s as a long decimal * integer. * * Return: On success, sets @result to the integer represented by the string * and returns 0. Returns -EINVAL or -ERANGE on failure. */ int match_u64(substring_t *s, u64 *result) { … } EXPORT_SYMBOL(…); /** * match_octal - scan an octal representation of an integer from a substring_t * @s: substring_t to be scanned * @result: resulting integer on success * * Description: Attempts to parse the &substring_t @s as an octal integer. * * Return: On success, sets @result to the integer represented by the string * and returns 0. Returns -EINVAL or -ERANGE on failure. */ int match_octal(substring_t *s, int *result) { … } EXPORT_SYMBOL(…); /** * match_hex - scan a hex representation of an integer from a substring_t * @s: substring_t to be scanned * @result: resulting integer on success * * Description: Attempts to parse the &substring_t @s as a hexadecimal integer. * * Return: On success, sets @result to the integer represented by the string * and returns 0. Returns -EINVAL or -ERANGE on failure. */ int match_hex(substring_t *s, int *result) { … } EXPORT_SYMBOL(…); /** * match_wildcard - parse if a string matches given wildcard pattern * @pattern: wildcard pattern * @str: the string to be parsed * * Description: Parse the string @str to check if matches wildcard * pattern @pattern. The pattern may contain two types of wildcards: * '*' - matches zero or more characters * '?' - matches one character * * Return: If the @str matches the @pattern, return true, else return false. */ bool match_wildcard(const char *pattern, const char *str) { … } EXPORT_SYMBOL(…); /** * match_strlcpy - Copy the characters from a substring_t to a sized buffer * @dest: where to copy to * @src: &substring_t to copy * @size: size of destination buffer * * Description: Copy the characters in &substring_t @src to the * c-style string @dest. Copy no more than @size - 1 characters, plus * the terminating NUL. * * Return: length of @src. */ size_t match_strlcpy(char *dest, const substring_t *src, size_t size) { … } EXPORT_SYMBOL(…); /** * match_strdup - allocate a new string with the contents of a substring_t * @s: &substring_t to copy * * Description: Allocates and returns a string filled with the contents of * the &substring_t @s. The caller is responsible for freeing the returned * string with kfree(). * * Return: the address of the newly allocated NUL-terminated string or * %NULL on error. */ char *match_strdup(const substring_t *s) { … } EXPORT_SYMBOL(…);