PHP - Error en PHP

<?php

	session_start();

	include_once "class/class_Core.php";

	include_once "class/class_General.php";

	$db = new ezSQL_mysql(DB_USER,DB_PASSWORD,DB_NAME,DB_HOST);

	if(!empty($_POST)){

			$usuario          =  htmlentities(trim(stripslashes($_POST['usuario'])));

			$contrasena       =  htmlentities(trim(stripslashes($_POST['contrasena'])));

			$contrasena2      =  htmlentities(trim(stripslashes($_POST['contrasena'])));

			$usuarioStrlen    = strlen($usuario);

			$contrasenaStrlen = strlen($contrasena);

			if($usuarioStrlen < 20 && $contrasenaStrlen < 20){

				$sqlcmd 	="	SELECT  proveedor, contrasena, nom_banco, num_cuenta, tipo_pago

								FROM  	proveedor

								WHERE 	proveedor = '$usuario' AND contrasena = '$contrasena' ";

				$rs         = $db->get_row($sqlcmd);

				$proveedor  = $rs->proveedor;

				$contrasena = $rs->contrasena;

				$nom_banco  = $rs->nom_banco;

				$num_cuenta = $rs->num_cuenta;

				$tipo_pago  = $rs->tipo_pago;

				if(empty($rs)){

					$sqlcmd2 	 ="	SELECT  a.proveedor, a.usuario, a.clave, a.existencias, a.ventas, a.ordencompra,

											a.cheques, a.promocontrol, b.nom_banco, b.num_cuenta, b.tipo_pago

									FROM  	usuarios  a

											INNER JOIN proveedor b ON  a.proveedor = b.proveedor

									WHERE 	a.usuario = '".$usuario."' AND a.clave = '".$contrasena2."'";

					$rs2          = $db->get_row($sqlcmd2);

					$proveedor2   = $rs2->proveedor;

					$usuario      = $rs2->usuario;

					$contrasena2  = $rs2->clave;

					$nom_banco2   = $rs2->nom_banco;

					$num_cuenta2  = $rs2->num_cuenta;

					$tipo_pago2   = $rs2->tipo_pago;

					$existencias  = $rs2->existencias;

					$ventas       = $rs2->ventas;

					$ordencompra  = $rs2->ordencompra;

					$cheques      = $rs2->cheques;

					$promocontrol = $rs2->promocontrol;

				}

				if (!empty($proveedor) && !empty($contrasena)){

					$_SESSION["proveedor"]  = $proveedor;

					$_SESSION["contrasena"] = $contrasena;

					$_SESSION["nom_banco"]  = $nom_banco;

					$_SESSION["num_cuenta"] = $num_cuenta;

					$_SESSION["tipo_pago"]  = $tipo_pago;

					header("Location: agree.php");

				} elseif (!empty($usuario) && !empty($contrasena2) && !empty($proveedor2)) {

					$_SESSION["proveedor"]    = $proveedor2;

					$_SESSION["usuario"]      = $usuario;

					$_SESSION["clave"]   	  = $clave;

					$_SESSION["nom_banco"]    = $nom_banco2;

					$_SESSION["num_cuenta"]   = $num_cuenta2;

					$_SESSION["tipo_pago"]    = $tipo_pago2;

					$_SESSION["existencias"]  = $existencias;

					$_SESSION["ventas"]       = $ventas;

					$_SESSION["ordencompra"]  = $ordencompra;

					$_SESSION["cheques"]      = $cheques;

					$_SESSION["promocontrol"] = $promocontrol;

					header("Location: agree.php");

				} else {

				 	$error = 'Usuario o contraseña no son validos';

					header( 'Location: index.php?error=$error' );

				}

			} else {

				$error = 'Acceso denegado1';

			 	header( 'Location: index.php?error=$error' );

			}

	} else {

			$error = 'Acceso denegado';

			header( 'Location: index.php?error=$error' );

}

?>

<?php

	/**********************************************************************

	*Author: Justin Vincent (jv@jvmultimedia.com)

	*Web...: http://twitter.com/justinvincent

	*Name..: ezSQL_mysql

	*Desc..: mySQL component (part of ezSQL databse abstraction library)

	*

	*/

	/**********************************************************************

	*ezSQL error strings - mySQL

	*/

	// ==================================================================

	// User Settings -- CHANGE HERE

	define("DB_USER", "alsuper_provee1");			// <-- mysql db user

	define("DB_PASSWORD", "Alsuper01");		// <-- mysql db password

	define("DB_NAME", "alsuper_proveedor");			// <-- mysql db pname

	define("DB_HOST", "72.249.76.230");				// <-- mysql server host

	/**********************************************************************

	*ezSQL Database specific class - mySQL

	*/

	$ezsql_mysql_str = array

	(

		1 => 'Require $dbuser and $dbpassword to connect to a database server',

		2 => 'Error establishing mySQL database connection. Correct user/password? Correct hostname? Database server running?',

		3 => 'Require $dbname to select a database',

		4 => 'mySQL database connection is not active',

		5 => 'Unexpected error while trying to select database'

	);

	if ( ! function_exists ('mysql_connect') ) die('<b>Fatal Error:</b> ezSQL_mysql requires mySQL Lib to be compiled and or linked in to the PHP engine');

	if ( ! class_exists ('ezSQLcore') ) die('<b>Fatal Error:</b> ezSQL_mysql requires ezSQLcore (ez_sql_core.php) to be included/loaded before it can be used');

	class ezSQL_mysql extends ezSQLcore

	{

		var $dbuser = false;

		var $dbpassword = false;

		var $dbname = false;

		var $dbhost = false;

		/**********************************************************************

		*  Constructor - allow the user to perform a qucik connect at the

		*  same time as initialising the ezSQL_mysql class

		*/

		function ezSQL_mysql($dbuser='alsuper_provee1', $dbpassword='Alsuper01', $dbname='alsuper_proveedor', $dbhost='72.249.76.230')

		{

			$this->dbuser = $dbuser;

			$this->dbpassword = $dbpassword;

			$this->dbname = $dbname;

			$this->dbhost = $dbhost;

		}

		/**********************************************************************

		*  Short hand way to connect to mySQL database server

		*  and select a mySQL database at the same time

		*/

		function quick_connect($dbuser='', $dbpassword='', $dbname='', $dbhost='localhost')

		{

			$return_val = false;

			if ( ! $this->connect($dbuser, $dbpassword, $dbhost,true) ) ;

			else if ( ! $this->select($dbname) ) ;

			else $return_val = true;

			return $return_val;

		}

		/**********************************************************************

		*  Try to connect to mySQL database server

		*/

		function connect($dbuser='', $dbpassword='', $dbhost='localhost')

		{

			global $ezsql_mysql_str; $return_val = false;

			// Must have a user and a password

			if ( ! $dbuser )

			{

				$this->register_error($ezsql_mysql_str[1].' in '.__FILE__.' on line '.__LINE__);

				$this->show_errors ? trigger_error($ezsql_mysql_str[1],E_USER_WARNING) : null;

			}

			// Try to establish the server database handle

			else if ( ! $this->dbh = @mysql_connect($dbhost,$dbuser,$dbpassword,true) )

			{

				$this->register_error($ezsql_mysql_str[2].' in '.__FILE__.' on line '.__LINE__);

				$this->show_errors ? trigger_error($ezsql_mysql_str[2],E_USER_WARNING) : null;

			}

			else

			{

				$this->dbuser = $dbuser;

				$this->dbpassword = $dbpassword;

				$this->dbhost = $dbhost;

				$return_val = true;

			}

			return $return_val;

		}

		/**********************************************************************

		*  Try to select a mySQL database

		*/

		function select($dbname='')

		{

			global $ezsql_mysql_str; $return_val = false;

			// Must have a database name

			if ( ! $dbname )

			{

				$this->register_error($ezsql_mysql_str[3].' in '.__FILE__.' on line '.__LINE__);

				$this->show_errors ? trigger_error($ezsql_mysql_str[3],E_USER_WARNING) : null;

			}

			// Must have an active database connection

			else if ( ! $this->dbh )

			{

				$this->register_error($ezsql_mysql_str[4].' in '.__FILE__.' on line '.__LINE__);

				$this->show_errors ? trigger_error($ezsql_mysql_str[4],E_USER_WARNING) : null;

			}

			// Try to connect to the database

			else if ( !@mysql_select_db($dbname,$this->dbh))

			{

				// Try to get error supplied by mysql if not use our own

				if ( !$str = @mysql_error($this->dbh))

					  $str = $ezsql_mysql_str[5];

				$this->register_error($str.' in '.__FILE__.' on line '.__LINE__);

				$this->show_errors ? trigger_error($str,E_USER_WARNING) : null;

			}

			else

			{

				$this->dbname = $dbname;

				$return_val = true;

			}

			return $return_val;

		}

		/**********************************************************************

		*  Format a mySQL string correctly for safe mySQL insert

		*  (no mater if magic quotes are on or not)

		*/

		function escape($str)

		{

			return mysql_escape_string(stripslashes($str));

		}

		/**********************************************************************

		*  Return mySQL specific system date syntax

		*  i.e. Oracle: SYSDATE Mysql: NOW()

		*/

		function sysdate()

		{

			return 'NOW()';

		}

		/**********************************************************************

		*  Perform mySQL query and try to detirmin result value

		*/

		function query($query)

		{

			// Initialise return

			$return_val = 0;

			// Flush cached values..

			$this->flush();

			// For reg expressions

			$query = trim($query);

			// Log how the function was called

			$this->func_call = "\$db->query(\"$query\")";

			// Keep track of the last query for debug..

			$this->last_query = $query;

			// Count how many queries there have been

			$this->num_queries++;

			// Use core file cache function

			if ( $cache = $this->get_cache($query) )

			{

				return $cache;

			}

			// If there is no existing database connection then try to connect

			if ( ! isset($this->dbh) || ! $this->dbh )

			{

				$this->connect($this->dbuser, $this->dbpassword, $this->dbhost);

				$this->select($this->dbname);

			}

			// Perform the query via std mysql_query function..

			$this->result = @mysql_query($query,$this->dbh);

			// If there is an error then take note of it..

			if ( $str = @mysql_error($this->dbh) )

			{

				$is_insert = true;

				$this->register_error($str);

				$this->show_errors ? trigger_error($str,E_USER_WARNING) : null;

				return false;

			}

			// Query was an insert, delete, update, replace

			$is_insert = false;

			if ( preg_match("/^(insert|delete|update|replace)\s+/i",$query) )

			{

				$this->rows_affected = @mysql_affected_rows();

				// Take note of the insert_id

				if ( preg_match("/^(insert|replace)\s+/i",$query) )

				{

					$this->insert_id = @mysql_insert_id($this->dbh);

				}

				// Return number fo rows affected

				$return_val = $this->rows_affected;

			}

			// Query was a select

			else

			{

				// Take note of column info

				$i=0;

				while ($i < @mysql_num_fields($this->result))

				{

					$this->col_info[$i] = @mysql_fetch_field($this->result);

					$i++;

				}

				// Store Query Results

				$num_rows=0;

				while ( $row = @mysql_fetch_object($this->result) )

				{

					// Store relults as an objects within main array

					$this->last_result[$num_rows] = $row;

					$num_rows++;

				}

				@mysql_free_result($this->result);

				// Log number of rows the query returned

				$this->num_rows = $num_rows;

				// Return number of rows selected

				$return_val = $this->num_rows;

			}

			// disk caching of queries

			$this->store_cache($query,$is_insert);

			// If debug ALL queries

			$this->trace || $this->debug_all ? $this->debug() : null ;

			return $return_val;

		}

		function limpiarpost() {

				foreach ($_POST as $p=>$d) {

					if(is_array($d)) {

						continue;

					}

					$_POST[$p]=addslashes(strip_tags($d));

				}

			}

		function alerta($tipo,$mensaje) {

			switch($tipo) {

			case "bien":

					echo "

						<div class='alert success'>$mensaje</div>

						";

			break;

			case "error":

					echo "

						<div class='alert warning'>$mensaje</div>

						";

			break;

			default:

			return false;

			}

		}

	}

?>