The Regular Expression Engine

The regular expression engine. More...

Functions
void	re_strlcpy (char *outstr, const char *instr, size_t outsz, regmatch_t rem)
size_t	re_strlen (regmatch_t rem)
bool	re_init (struct regeng *re_array)
bool	re_parse (re_callback_t re_callback, struct regeng *re_array, char *str)
#define	RE_MATCH(x)   (((x).rm_so != -1) && ((x).rm_eo != -1))
#define	RE_INVALID_ID   0xffffffff
#define	RE_REMATCH_MAX   32
#define	RE_REGENG_VALID(x)
#define	RE_REGENG_END   { .re_id = RE_INVALID_ID, .re_exp = NULL }
typedef void	re_callback_t (uint32_t re_id, const char *str, regmatch_t *rematch, size_t rematch_max)

Detailed Description

The regular expression engine.

This module was written first by using regular POSIX-regex. Since there's no POSIX regex support in MinGW, it was necessary to use an external regex library – PCRE.

Note

This is the only module that heavily relies on 3rd party libraries.

Macro Definition Documentation

#define RE_INVALID_ID   0xffffffff

Marker for end of regeng

#define RE_MATCH

(

x)

(((x).rm_so != -1) && ((x).rm_eo != -1))

This macro checks if a regmatch_t x was matched

Return values

true	If x was matched
false	If x was not matched

#define RE_REGENG_END   { .re_id = RE_INVALID_ID, .re_exp = NULL }

The last element of the regeng array must be this macro

#define RE_REGENG_VALID

(

x)

Value:

(((x)->re_id  != RE_INVALID_ID) && \
                             ((x)->re_exp != NULL))

Check if the regeng is valid

#define RE_REMATCH_MAX   32

Maximum number of regmatch_t structures

Typedef Documentation

typedef void re_callback_t(uint32_t re_id, const char *str, regmatch_t *rematch, size_t rematch_max)

The regeng callback

Note

That rematch may contain fewer matches than rematch_max. RE_MATCH should be used to check if a regmatch_t element is valid or not.

Parameters

[in]	re_id	This is the re_id from The Regular Expression Engine
[in]	str	This is the full string that had a match
[in]	rematch	Array of matched parameters
[in]	rematch_max	Number of matches in rematch, maximum RE_REMATCH_MAX

Function Documentation

bool re_init

(

struct regeng *

re_array)

Initialize the regular expression engine

Scan the regex array and compile the regular expressions in the re_exp field

Parameters

[in]

re_array

Array of regular expression structures

Returns

true on success, or false if any of the regular expressions failed to initialize.

bool re_parse	(	re_callback_t	re_callback,
		struct regeng *	re_array,
		char *	str
	)

This is the main loop of the regular expression engine

Note

re_array must have been initialized with re_init() before calling this function

Parameters

[in]	re_array	Initialized regular expression array
[in]	re_callback	Callback that will be called for processing any matches
[in]	str	String to match

Returns

Currently returns always true

void re_strlcpy	(	char *	outstr,
		const char *	instr,
		size_t	outsz,
		regmatch_t	rem
	)

Extract a sub-string that was matched by the regular expression in rem

Note

This function will properly truncate the string if the output string is too small and place a '\0' at the end without causing any overflows.

Parameters

[out]	outstr	Sub-string pointer
[in]	instr	Full-string on which regex was performed
[in]	outsz	Maximum size of the output sub-string
[in]	rem	The regex match structure

size_t re_strlen

(

regmatch_t

rem)

Returns the length of the matched regex

Parameters

[in]

rem

Matched regex

Returns

Number of characters that was matched in rem