Add NODE_RAW_ENV to mirror host env vars under node

One can still use `-sDETERMINISITIC` to avoid this behaviour.

Fixes: #18816, #25791

Author: sbc100

ChangeLog.md

@@ -1099,6 +1099,10 @@ See docs/process.md for more on how version tagging works.
 - The `emscripten_proxy_async_with_callback` API was replaced with a simpler
   `emscripten_proxy_callback` API that takes a second callback to be called if
   the worker thread dies before completing the proxied work.  
+- When running under node the full set of environment variables (i.e.
+  process.env) are now reflected to running emscripten process (via e.g.
+  getenv).  If you don't want this behaviour `-sDETERMINISTIC` can be used
+  to disable this can give fake envinonment instead.
 
 3.1.32 - 02/17/23
 -----------------

site/source/docs/tools_reference/settings_reference.rst

@@ -1506,6 +1506,18 @@ handles permissions and errors and so forth may be noticeable.
 
 Default value: false
 
+.. _node_raw_env:
+
+NODE_RAW_ENV
+============
+
+When running under nodejs, expose the underlying OS environment variables.
+This is similiar to how ``NODERAWFS`` exporses the underlying FS.
+This setting gets enabled by default when ``NODERAWFS`` is enabled, but can
+also be controlled separatley.
+
+Default value: false
+
 .. _node_code_caching:
 
 NODE_CODE_CACHING

src/lib/libwasi.js

@@ -67,6 +67,12 @@ var WasiLibrary = {
         '_': getExecutableName()
 #endif
       };
+#if ENVIRONMENT_MAY_BE_NODE && NODE_RAW_ENV
+      if (ENVIRONMENT_IS_NODE) {
+        // Under node we mirror then entire outer environment
+        env = process.env;
+      }
+#endif
       // Apply the user-provided values, if any.
       for (var x in ENV) {
         // x is a key in ENV; if ENV[x] is undefined, that means it was

src/settings.js

@@ -1035,6 +1035,12 @@ var FORCE_FILESYSTEM = false;
 // [link]
 var NODERAWFS = false;
 
+// When running under nodejs, expose the underlying OS environment variables.
+// This is similiar to how ``NODERAWFS`` exporses the underlying FS.
+// This setting gets enabled by default when ``NODERAWFS`` is enabled, but can
+// also be controlled separatley.
+var NODE_RAW_ENV = false;
+
 // This saves the compiled wasm module in a file with name
 // ``$WASM_BINARY_NAME.$V8_VERSION.cached``
 // and loads it on subsequent runs. This caches the compiled wasm code from

test/test_other.py

@@ -7841,6 +7841,23 @@ def test_override_js_execution_environment(self):
         seen = self.run_js('test.js', engine=engine, assert_returncode=NON_ZERO)
         self.assertContained('Module.ENVIRONMENT has been deprecated. To force the environment, use the ENVIRONMENT compile-time option (for example, -sENVIRONMENT=web or -sENVIRONMENT=node', seen)
 
+  @requires_node
+  @with_env_modify({'FOO': 'bar'})
+  @parameterized({
+    '': ([], '|(null)|\n'),
+    'raw_fs': (['-sNODERAWFS'], '|bar|\n'),
+    'raw_env': (['-sNODE_RAW_ENV'], '|bar|\n'),
+  })
+  def test_node_environ(self, args, expected):
+     create_file('src.c', r'''
+      #include <stdlib.h>
+      #include <stdio.h>
+      int main() {
+        printf("|%s|\n", getenv("FOO"));
+      }
+    ''')
+     self.do_runf('src.c', expected, cflags=args)
+
   def test_override_c_environ(self):
     create_file('pre.js', r'''
       Module.preRun = () => { ENV.hello = '💩 world'; ENV.LANG = undefined; }
@@ -13655,8 +13672,6 @@ def test_fs_icase(self):
 
   @with_all_fs
   def test_std_filesystem(self):
-    if (WINDOWS or MACOS) and self.get_setting('NODERAWFS'):
-      self.skipTest('Rawfs directory removal works only on Linux')
     self.do_other_test('test_std_filesystem.cpp')
 
   def test_strict_js_closure(self):

tools/link.py

@@ -1884,6 +1884,9 @@ def get_full_import_name(name):
   if settings.PTHREADS:
     settings.REQUIRED_EXPORTS.append('_emscripten_tls_init')
 
+  if settings.NODERAWFS:
+    default_setting('NODE_RAW_ENV', 1)
+
   settings.PRE_JS_FILES = options.pre_js
   settings.POST_JS_FILES = options.post_js