fix: thread safety regarding env vars (#633)

Fix: #632

Author: Sébastien HOUZÉ

src/Configuration.php

@@ -93,8 +93,8 @@ public static function create(array $options)
             foreach ($fallbackGroup as $option => $envVariableNames) {
                 $envVariableNames = (array) $envVariableNames;
                 foreach ($envVariableNames as $envVariableName) {
-                    if (false !== $value = \getenv($envVariableName)) {
-                        $options[$option] = $value;
+                    if (isset($_SERVER[$envVariableName])) {
+                        $options[$option] = $_SERVER[$envVariableName];
 
                         break;
                     }

src/Credentials/IniFileLoader.php

@@ -65,13 +65,13 @@ public function loadProfiles(array $filepaths): array
     private function getHomeDir(): string
     {
         // On Linux/Unix-like systems, use the HOME environment variable
-        if (false !== $homeDir = \getenv('HOME')) {
+        if (\is_string($homeDir = $_SERVER['HOME'] ?? null)) {
             return $homeDir;
         }
 
         // Get the HOMEDRIVE and HOMEPATH values for Windows hosts
-        $homeDrive = \getenv('HOMEDRIVE');
-        $homePath = \getenv('HOMEPATH');
+        $homeDrive = $_SERVER['HOMEDRIVE'] ?? null;
+        $homePath = $_SERVER['HOMEPATH'] ?? null;
 
         return ($homeDrive && $homePath) ? $homeDrive . $homePath : '/';
     }

tests/Unit/ConfigurationTest.php

@@ -15,7 +15,7 @@ class ConfigurationTest extends TestCase
     public function testCreate($config, $env, $expected)
     {
         foreach ($env as $key => $value) {
-            putenv("$key=$value");
+            $_SERVER[$key] = $value;
         }
 
         try {
@@ -25,7 +25,7 @@ public function testCreate($config, $env, $expected)
             }
         } finally {
             foreach ($env as $key => $value) {
-                putenv($key);
+                unset($_SERVER[$key]);
             }
         }
     }