move resource to exec function

CHANGELOG.md

@@ -4,8 +4,9 @@ All notable changes to this project will be documented in this file. This projec
 
 ## 2.5.0
 
++ [#95](https://github.com/php-mod/curl/issues/95) Potential memory leak prevention where curl object was not destroyed due to object reference.
 + [#94](https://github.com/php-mod/curl/pull/94) Added method to retrieve all curl options from current object.
-+ [#93](https://github.com/php-mod/curl/pull/93) Text and Coding Standards update
++ [#93](https://github.com/php-mod/curl/pull/93) Text and Coding Standards update.
 
 ## 2.4.0 (29. August 2022)
 

src/Curl/Curl.php

@@ -172,7 +172,7 @@ private function init()
         $this->setOpt(CURLINFO_HEADER_OUT, true);
         $this->setOpt(CURLOPT_HEADER, false);
         $this->setOpt(CURLOPT_RETURNTRANSFER, true);
-        $this->setOpt(CURLOPT_HEADERFUNCTION, array($this, 'addResponseHeaderLine'));
+
         return $this;
     }
 
@@ -208,6 +208,7 @@ public function addResponseHeaderLine($curl, $header_line)
      */
     public function exec()
     {
+        $this->setOpt(CURLOPT_HEADERFUNCTION, array($this, 'addResponseHeaderLine'));
         $this->response_headers = array();
         $this->response = curl_exec($this->curl);
         $this->curl_error_code = curl_errno($this->curl);
@@ -220,7 +221,7 @@ public function exec()
         $this->request_headers = preg_split('/\r\n/', curl_getinfo($this->curl, CURLINFO_HEADER_OUT), -1, PREG_SPLIT_NO_EMPTY);
         $this->http_error_message = $this->error ? (isset($this->response_headers['0']) ? $this->response_headers['0'] : '') : '';
         $this->error_message = $this->curl_error ? $this->getErrorMessage() : $this->http_error_message;
-
+        $this->setOpt(CURLOPT_HEADERFUNCTION, null);
         return $this->error_code;
     }