Skip loading .data bundle and mapping corresponding files when running as a worker for pthread (emscripten-core#15644)

Author: shanumante-sc

tests/manual_download_data.cpp

@@ -14,10 +14,10 @@ int main()
 	char str[128] = {};
 	fread(str, 1, sizeof(str), handle);
 	printf("str: %s\n", str);
-	assert(!strcmp(str, "Hello!"));
+	const bool success = (strcmp(str, "Hello!") == 0);
+	assert(success);
 	printf("OK\n");
 #ifdef REPORT_RESULT
-	int result = EM_ASM_INT({return Module.manuallyDownloadedData;});
-	REPORT_RESULT(result);
+	REPORT_RESULT(success);
 #endif
 }

tests/manual_download_data.html

@@ -184,12 +184,12 @@
         return Module['downloadedData'];
       }
 
-      var dataDownload = download('manual_download_data.data').then(function(data) {
+      var dataDownload = download('/test/manual_download_data.data').then(function(data) {
         console.log('downloaded data file');
-        Module.manuallyDownloadedData = 1;
         Module['downloadedData'] = data;
         var jsDownload = download('manual_download_data.js').then(function(data) {
           console.log('downloaded js file');
+          Module['mainScriptUrlOrBlob'] = new Blob([data]);
           addScriptToDom(data);
         });
       });

tests/test_browser.py

@@ -412,13 +412,23 @@ def make_main_two_files(path1, path2, nonexistingpath):
     self.btest_exit('main.cpp', args=['--pre-js', 'pre.js', '--use-preload-plugins'])
 
   # Tests that user .html shell files can manually download .data files created with --preload-file cmdline.
-  def test_preload_file_with_manual_data_download(self):
+  @parameterized({
+    'default': ([],),
+    'pthreads': (['-pthread', '-sPROXY_TO_PTHREAD', '-sEXIT_RUNTIME'],),
+  })
+  @requires_threads
+  def test_preload_file_with_manual_data_download(self, args):
     src = test_file('manual_download_data.cpp')
 
     create_file('file.txt', '''Hello!''')
 
-    self.compile_btest([src, '-o', 'manual_download_data.js', '--preload-file', 'file.txt@/file.txt'])
+    self.compile_btest([src, '-o', 'manual_download_data.js', '--preload-file', 'file.txt@/file.txt'] + args)
     shutil.copyfile(test_file('manual_download_data.html'), 'manual_download_data.html')
+
+    # Move .data file out of server root to ensure that getPreloadedPackage is actually used
+    os.mkdir('test')
+    shutil.move('manual_download_data.data', 'test/manual_download_data.data')
+
     self.run_browser('manual_download_data.html', 'Hello!', '/report_result?1')
 
   # Tests that if the output files have single or double quotes in them, that it will be handled by

tools/file_packager.py

@@ -291,7 +291,10 @@ def main():
   }
   Module.expectedDataFileDownloads++;
   (function() {
-   var loadPackage = function(metadata) {
+    // When running as a pthread, FS operations are proxied to the main thread, so we don't need to
+    // fetch the .data bundle on the worker
+    if (Module['ENVIRONMENT_IS_PTHREAD']) return;
+    var loadPackage = function(metadata) {
   '''
 
   code = '''

tools/js_manipulation.py

@@ -17,6 +17,7 @@ def add_files_pre_js(user_pre_js, files_pre_js):
   return files_pre_js + '''
     // All the pre-js content up to here must remain later on, we need to run
     // it.
+    if (Module['ENVIRONMENT_IS_PTHREAD']) Module['preRun'] = [];
     var necessaryPreJSTasks = Module['preRun'].slice();
   ''' + user_pre_js + '''
     if (!Module['preRun']) throw 'Module.preRun should exist because file support used it; did a pre-js delete it?';