/* 
*
*  ProLinga-Web
*
*  Copyright (C) 2002-2008 Xobas Software.
*  All rights reserved.
*  
*  This file is part of ProLinga-Web.
*
*  ProLinga-Web is free software: you can redistribute it and/or modify
*  it under the terms of the GNU General Public License as published by
*  the Free Software Foundation, either version 3 of the License, or
*  (at your option) any later version.
*
*  ProLinga-Web is distributed in the hope that it will be useful,
*  but WITHOUT ANY WARRANTY; without even the implied warranty of
*  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
*  GNU General Public License for more details.
*
*  You should have received a copy of the GNU General Public License
*  along with ProLinga-Web.  If not, see <http://www.gnu.org/licenses/>.
*
*  More information is available at the following addresses:
*
*  Website     : http://www.prolinga.org
*
*  Email       : prolinga-list@prolinga.org
*
*
*/

#include "WebCommon.h"
#include <libxml/xmlmemory.h>
#include <libxml/parser.h>
#include "WCWebCommand.hpp"
#include "WebProcess.hpp"
#include "GetCgiVars.hpp"

/* The following code (x2c) was lifted from NCSA's sample program util.c */
/* Convert a two-char hex string into the char it represents. */
char x2c(char *what)
{
	register char digit;

	digit = (what[0] >= 'A' ? ((what[0] & 0xdf) - 'A')+10 : (what[0] - '0'));
	digit *= 16;
	digit += (what[1] >= 'A' ? ((what[1] & 0xdf) - 'A')+10 : (what[1] - '0'));
	return(digit);
}

/* The following code (unescape_url) was lifted from NCSA's sample program util.c */
/* Reduce any %xx escape sequences to the characters they represent. */
void unescape_url(char *url)
{
	register int i,j;

	for(i=0,j=0; url[j]; ++i,++j)
	 {
		if((url[i] = url[j]) == '%')
		{
			url[i] = x2c(&url[j+1]);
			j+= 2;
		}
	}
	url[i] = '\0' ;
}

/* The following code (getcgivars) was written by James Marshall */
/* http://www.jmarshall.com/easy/cgi/ */

/* Read the CGI input and place all name/val pairs into list.        */
/* Returns list containing name1, value1, name2, value2, ... , NULL  */
char **GetCgiVars()
{
	register int i;
	char *request_method;
	int content_length;
	char *cgiinput;
	char **cgivars;
	char **pairlist;
	int paircount;
	char *nvpair;
	char *eqpos;
                                                                                                                                               
	/** Depending on the request method, read all CGI input into cgiinput. **/
	request_method= getenv("REQUEST_METHOD");

	if (!strcmp(request_method, "GET") || !strcmp(request_method, "HEAD") )
	 {
	        /* Some servers apparently don't provide QUERY_STRING if it's empty, */
		/*   so avoid strdup()'ing a NULL pointer here.                      */
		char *qs ;
		qs= getenv("QUERY_STRING") ;
		cgiinput= strdup(qs  ? qs  : "") ;
	}
	else if (!strcmp(request_method, "POST"))
	{
		/* strcasecmp() is not supported in Windows-- use strcmpi() instead */
		if ( strcasecmp(getenv("CONTENT_TYPE"), "application/x-www-form-urlencoded"))
		{
			printf("Content-Type: text/plain\n\n");
			printf("getcgivars(): Unsupported Content-Type.\n");
			exit(1);
		}
		if ( !(content_length = atoi(getenv("CONTENT_LENGTH"))) )
		{
			printf("Content-Type: text/plain\n\n");
			printf("getcgivars(): No Content-Length was sent with the POST request.\n");
			exit(1);
		}
		if ( !(cgiinput= (char *) malloc(content_length+1)) )
		{
			printf("Content-Type: text/plain\n\n");
			printf("getcgivars(): Couldn't malloc for cgiinput.\n");
			exit(1);
		}
		if (!fread(cgiinput, content_length, 1, stdin))
		{
			printf("Content-Type: text/plain\n\n");
			printf("getcgivars(): Couldn't read CGI input from STDIN.\n");
			exit(1);
		}
		cgiinput[content_length]='\0';
	}
	else
	{
		printf("Content-Type: text/plain\n\n");
		printf("getcgivars(): Unsupported REQUEST_METHOD.\n");
		exit(1);
	}
                                                                                                                                               
	/** Change all plusses back to spaces. **/
	for (i=0; cgiinput[i]; i++) if (cgiinput[i] == '+') cgiinput[i] = ' ' ;
                                                                                                                                             
	/** First, split on "&" and ";" to extract the name-value pairs into **/
	/**   pairlist.                                                      **/
	pairlist= (char **) malloc(256*sizeof(char **));
	paircount= 0;
	nvpair= strtok(cgiinput, "&;");
	while (nvpair)
	{
		pairlist[paircount++]= strdup(nvpair);
		if (!(paircount%256))
			pairlist= (char **) realloc(pairlist,(paircount+256)*sizeof(char **));
		nvpair= strtok(NULL, "&;");
	}
	pairlist[paircount]= 0 ;    /* terminate the list with NULL */
                                                                                                                                               
	/** Then, from the list of pairs, extract the names and values. **/
	cgivars= (char **) malloc((paircount*2+1)*sizeof(char **));
	for (i= 0; i<paircount; i++)
	{
		if ((eqpos=strchr(pairlist[i], '=')))
		{
			*eqpos= '\0';
			unescape_url(cgivars[i*2+1]= strdup(eqpos+1));
		}
		else
		{
			unescape_url(cgivars[i*2+1]= strdup(""));
		}
		unescape_url(cgivars[i*2]= strdup(pairlist[i]));
	}
	cgivars[paircount*2]= 0;   /* terminate the list with NULL */
                                                                                                                                               
	/** Free anything that needs to be freed. **/
	free(cgiinput);
	for (i=0; pairlist[i]; i++) free(pairlist[i]);
	free(pairlist);
                                                                                                                                               
	/** Return the list of name-value strings. **/
	return cgivars ;
}