Fix for php 7.4

.travis.yml

@@ -68,6 +68,8 @@ matrix:
     env: DB=mariadb
   - php: '7.2'
     env: DB=mariadb
+  - php: '7.3'
+    env: DB=mariadb
   - php: '5.6'
     env: DB=postgresql
   - php: '7.0'
@@ -76,6 +78,8 @@ matrix:
     env: DB=postgresql
   - php: '7.2'
     env: DB=postgresql
+  - php: '7.3'
+    env: DB=postgresql
   - php: nightly
     env: DB=postgresql
 

htdocs/core/lib/functions2.lib.php

@@ -1347,7 +1347,7 @@ function hexbin($hexa)
     $strLength = dol_strlen($hexa);
     for ($i = 0; $i < $strLength; $i++)
     {
-        $bin .= str_pad(decbin(hexdec($hexa{$i})), 4, '0', STR_PAD_LEFT);
+        $bin .= str_pad(decbin(hexdec($hexa[$i])), 4, '0', STR_PAD_LEFT);
     }
     return $bin;
 }