From 23431fafd91f2debcfdd93f44663f95f996a08db Mon Sep 17 00:00:00 2001
From: Richard Hofman <richard.hofman@orionhealth.com>
Date: Tue, 8 Mar 2016 19:39:39 +1300
Subject: [PATCH] Added LDAP pagination for user import.

---
 app/controllers/admin/UsersController.php | 45 ++++++++++++++++++-----
 1 file changed, 35 insertions(+), 10 deletions(-)

diff --git a/app/controllers/admin/UsersController.php b/app/controllers/admin/UsersController.php
index 84a2141afb..f5741fc6f0 100755
--- a/app/controllers/admin/UsersController.php
+++ b/app/controllers/admin/UsersController.php
@@ -1249,17 +1249,42 @@ class UsersController extends AdminController {
             return Redirect::route('users')->with('error', Lang::get('admin/users/message.error.ldap_could_not_bind').ldap_error($ldapconn));
         }
 
-        // Perform the search
-        $search_results = @ldap_search($ldapconn, $base_dn, '('.$filter.')');
-        if (!$search_results) {
-            return Redirect::route('users')->with('error', Lang::get('admin/users/message.error.ldap_could_not_search').ldap_error($ldapconn));
-        }
+	// Set up LDAP pagination for very large databases
+	// @author Richard Hofman
+	$page_size = 500;
+	$cookie = '';
+	$result_set = array();
+	$global_count = 0;
 
-        // Get results
-        $results = @ldap_get_entries($ldapconn, $search_results);
-        if (!$results) {
-            return Redirect::route('users')->with('error', Lang::get('admin/users/message.error.ldap_could_not_get_entries').ldap_error($ldapconn));
-        }
+        // Perform the search
+	do {
+		// Paginate (non-critical, if not supported by server)
+		ldap_control_paged_result($ldapconn, $page_size, false, $cookie);
+
+        	$search_results = ldap_search($ldapconn, $base_dn, '('.$filter.')');
+
+	        if (!$search_results) {
+	            return Redirect::route('users')->with('error', Lang::get('admin/users/message.error.ldap_could_not_search').ldap_error($ldapconn));
+	        }
+
+	        // Get results from page
+	        $results = ldap_get_entries($ldapconn, $search_results);
+	        if (!$results) {
+	            return Redirect::route('users')->with('error', Lang::get('admin/users/message.error.ldap_could_not_get_entries').ldap_error($ldapconn));
+	        }
+
+		// Add results to result set
+		$global_count += $results['count'];
+		$result_set = array_merge($result_set, $results);
+
+		ldap_control_paged_result_response($ldapconn, $search_results, $cookie);
+
+	} while ($cookie !== null && $cookie != '');
+
+	// Clean up after search
+	$result_set['count'] = $global_count;
+	$results = $result_set;
+	ldap_control_paged_result($ldapconn, 0);
 
         $summary = array();
         for ($i = 0; $i < $results["count"]; $i++) {