Commit adf9a351 authored by Andrew Morton's avatar Andrew Morton Committed by Linus Torvalds

[PATCH] Add lib/parser.c kernel-doc

From: Will Dyson <will_dyson@pobox.com>

Add documentation and comments to lib/parser.c and include/linux/parser.h
parent cb8d8fe9
/*
* linux/include/linux/parser.h
*
* Header for lib/parser.c
* Intended use of these functions is parsing filesystem argument lists,
* but could potentially be used anywhere else that simple option=arg
* parsing is required.
*/
/* associates an integer enumerator with a pattern string. */
struct match_token {
int token;
char *pattern;
......@@ -5,15 +16,16 @@ struct match_token {
typedef struct match_token match_table_t[];
/* Maximum number of arguments that match_token will find in a pattern */
enum {MAX_OPT_ARGS = 3};
/* Describe the location within a string of a substring */
typedef struct {
char *from;
char *to;
} substring_t;
int match_token(char *s, match_table_t table, substring_t args[]);
int match_token(char *, match_table_t table, substring_t args[]);
int match_int(substring_t *, int *result);
int match_octal(substring_t *, int *result);
int match_hex(substring_t *, int *result);
......
......@@ -11,6 +11,17 @@
#include <linux/slab.h>
#include <linux/string.h>
/**
* match_one: - Determines if a string matches a simple pattern
* @s: the string to examine for presense 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, char *p, substring_t args[])
{
char *meta;
......@@ -74,6 +85,20 @@ static int match_one(char *s, 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, match_table_t table, substring_t args[])
{
struct match_token *p;
......@@ -84,6 +109,16 @@ int match_token(char *s, match_table_t table, substring_t args[])
return p->token;
}
/**
* 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. On success, sets @result to the integer represented
* by the string and returns 0. Returns either -ENOMEM or -EINVAL on failure.
*/
static int match_number(substring_t *s, int *result, int base)
{
char *endp;
......@@ -103,27 +138,71 @@ static int match_number(substring_t *s, int *result, int base)
return ret;
}
/**
* 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. On
* success, sets @result to the integer represented by the string and returns 0.
* Returns either -ENOMEM or -EINVAL on failure.
*/
int match_int(substring_t *s, int *result)
{
return match_number(s, result, 0);
}
/**
* 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. On
* success, sets @result to the integer represented by the string and returns
* 0. Returns either -ENOMEM or -EINVAL on failure.
*/
int match_octal(substring_t *s, int *result)
{
return match_number(s, result, 8);
}
/**
* 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.
* On success, sets @result to the integer represented by the string and
* returns 0. Returns either -ENOMEM or -EINVAL on failure.
*/
int match_hex(substring_t *s, int *result)
{
return match_number(s, result, 16);
}
/**
* match_strcpy: - copies the characters from a substring_t to a string
* @to: string to copy characters to.
* @s: &substring_t to copy
*
* Description: Copies the set of characters represented by the given
* &substring_t @s to the c-style string @to. Caller guarantees that @to is
* large enough to hold the characters of @s.
*/
void match_strcpy(char *to, substring_t *s)
{
memcpy(to, s->from, s->to - s->from);
to[s->to - s->from] = '\0';
}
/**
* 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().
*/
char *match_strdup(substring_t *s)
{
char *p = kmalloc(s->to - s->from + 1, GFP_KERNEL);
......
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