mlex.h File Reference

Markup Language EXpression. More...

Go to the source code of this file.

Data Structures
struct	chunk_t
	the struct that is used to identify a piece of string More...
Functions
list_t *	mlmatch (char *data, char *exp, char *ret)
	Finds Markup Language chuks matching exp.
void	mlmatch_print_results (list_t *res, char *str)
	debug functions that prints the resul matrix
void	mlmatch_free_results (list_t *res)
	free the list of lists returned by mlmatch
char *	mlmatch_get_result (int x, int y, list_t *res, char *s)
	gets a cell from the result matrix

---

Detailed Description

Markup Language EXpression.

Author:

Enrico Tassi   <>

Definition in file mlex.h.

---

Function Documentation

list_t* mlmatch (  char *  data, char *  exp, char *  ret )

Finds Markup Language chuks matching exp. What is an ml-expression? Simply a regular expression with some more infos about murkups. Grammar: MLEX := MREGEX | MTAGEX | MLEX MLEX | '' MTAGEX := '{'REGEX'}' | '<'REGEX'>' MREGEX := '['REGEX']' | REGEX REGEX := regular expression Example: ".*<b>([0-9]*(Kb|Mb))</b>" This matches a generic size in bold. ".*<(b|i)>([0-9]*(Kb|Mb))</(b|i)>" This matches a generic size in bold or italics, obviously it doesn't check if it opens with a b and closes with a /i. "a<b>[c]{d}e{f}[g]<h>" This matches abdefgh, abeh and othe strigs created considering optionals the tags/strings between {} and [] Limitation: You can use regular expressions inside tags or outside tags,but you can't use regexp with tags. For example it is impossible to specify an arbutrary number of "<b>". A string, say an MREGEX not optional, cant start with [ since it is reserver for optional strings. You must put the expression into round brackets to avoid this. The parser is not really smart. It always alternates a string with a tag, so an xpression "<a><b>" is interpreted as this sequence of tokens: "","<a>","","<b>". What is an ml-get-expression? It is the counterpart of a ml-expression. It selects what is important and what not. Grammar: MLGEX := REGGEX TAGGEX | MLGEX MLGEX | '' TAGGEX := '<'EX'>' | '{'EX'}' REGGEX := EX | '['EX']' EX := 'X' | 'O' Example: If the ml-expression is ".*<b>.*<.*img.*src.*>.*</b>" and the ml-get-expression is "O<O>O<X>X<O>" and data is "<tt><b><img src="nice.jpg">hello</b>" mlmatch returns a list of length 2 (read: the nember of "X") the first defining "img src="nice.jpg"" and the second defining "hello". Remembre that if an optional string/tag is used in the ml-expression, the corrspong optional string/tag signature must be used in the ml-get-expression. A short explanation of how the engine works (considering the prevoius example): tokenize the strings: "<tt><b><img src="nice.jpg">hello</b>" becames "","<tt>","","<b>","","<img src="nice.jpg">","hello","</b>" ".*<b>.*<.*img.*src.*>.*</b>" becames ".*","<b>",".*","<.*img.*src.*>",".*","</b>" "O<O>O<X>X<O>" becames "O","<O>","O","<X>","X","<O>" The ml-expression matches perfectly the data starting from the third token, since each regexp matches the corresponding token. so we obtain this sub-list of tokens "","<b>","","<img src="nice.jpg">","hello","</b>" The sublist has the same length of the ret expression and selecting only the tokens with a corresponding X we obtain {"img src="nice.jpg"","hello".} Notes: data, exp and ret MUST be modifyable. they will not be altered, but during processing they may be accessed in write. Parameters: data  is a Markup Language file like an html page (must be modifyable) exp  is the ml-expression (must be modifyable) ret  is the ml-get-expression (must be modifyable) Returns: a list of list of chunk_t

void mlmatch_free_results (  list_t *  res  )

free the list of lists returned by mlmatch

char* mlmatch_get_result (  int  x, int  y, list_t *  res, char *  s )

gets a cell from the result matrix mlmatch returns a list of lists. this is a matrix. each line is the list of X fields. Example: src := "<b>hello</b> bad <i>guys</b>" exp := "<.*>.*</b>" ret := "<X>X<O>" calling rc = mlmatch(src,exp,ret); will return {{"b","hello"},  {"i","guys"} } and the respective coordinates are from 0,0 to 1,1. For example "hello" is 1,0. The returned poiter must be freed by the caller. Parameters: x  column y  row res  returned by mlmatch s  the src string Returns: a strdup of s chunked in the right position

void mlmatch_print_results (  list_t *  res, char *  str )

debug functions that prints the resul matrix

---