C Pattern Matching with PCRE and SLRE

[C] Pattern Matching with PCRE and SLRE - Printable Version

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+---- Thread: [C] Pattern Matching with PCRE and SLRE (/showthread.php?tid=4555941)

Pattern Matching with PCRE and SLRE - geekmorpheus403 - Nov 26, 2014

Ok,
I have been recently trying to do a pattern matching with regular expressions.I have to do this in C(No other language) .I have used slre library and wrote this:

Code 
#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#include "slre.h"

#include "slre.c"

int main(void)

{

    char* mystring = "potty <body class=\"admin-yokohoma admin-235\"> lovely baby :*";

    struct slre_cap caps[2];

    static const char* regex = "<body class=\".*(admin-).*(admin-).*\">";

    if(slre_match(regex,mystring, strlen(mystring), caps, 2, 1) > 0)

    {

        char buffer[100];

        printf("We have found it! Yay!\n");

        char* ptr = caps[0].ptr + 6;

        char* loc = strchr(ptr ,' ');

        int ttlsize = (int) (loc - ptr);

        printf("%d\n",ttlsize);

        strncpy(buffer,ptr,ttlsize);

        buffer[ttlsize] = '\0';

        printf("Matched:%s",buffer);

    }

}

This works fine for short string.But my problem is that I will have to check for this pattern in a whole web page source code about 60000 characters but unfortunately slre is not able to handle it for some reason.Whenever I use this code in that program to look for this pattern in webpage,It never ends.There is No Loops.The program doesn't terminate.And with smaller strings it is ok.But slow.

So I wanted to use PCRE.But I am not getting it how to use it.I tried downloading the library but pcre.h is not there.Can somebody show me how to use PCRE like this code.Starting from the download.Please I really need it.Or show me some other effective way to handle huge strings and matching patters please.

Best Regards.

* - -ceramic- - Nov 26, 2014

Regex is not suited to parse SGML.
Try this XML parser, it's really lightweight and will run a LOT faste
hxxp://tibleiz.net/asm-xml/tutorial.html

Also see hxxp://stackoverflow.com/questions/6751105/why-its-not-possible-to-use-regex-to-parse-html-xml-a-formal-explanation-in-la

* - Mouse❤️ - Nov 26, 2014

https://hackforums.net/showthread.php?tid=4553947 Don't make a new thread for the same problem.

* - geekmorpheus403 - Nov 26, 2014

(Nov 26, 2014 07:44 AM)-ceramic- Wrote: Regex is not suited to parse SGML.
Try this XML parser, it's really lightweight and will run a LOT faste

hxxp://tibleiz.net/asm-xml/tutorial.html

Also see hxxp://stackoverflow.com/questions/6751105/why-its-not-possible-to-use-regex-to-parse-html-xml-a-formal-explanation-in-la

Thanks Bro for clearing all the confusions,
I have looked it up.But can you give me a sample code how to use it.I have huge string which contains html source.I want to look for that Specific string pattern and return its matches.Can you show me with Asm-Xml.I googled it I cound't find helpful examples.

Best Regards.