[VM/Runtime] - Do not try to resolve exec path for default namespace

TEST=new test added
Bug:54516
Change-Id: I67b1fe7ee07db342d328e5272ddca5411fd5df28
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/345320
Reviewed-by: Zach Anderson <zra@google.com>
Commit-Queue: Siva Annamalai <asiva@google.com>

runtime/bin/process_android.cc

@@ -451,7 +451,7 @@ class ProcessStarter {
   // be reported to the parent.
   bool FindPathInNamespace(char* realpath, intptr_t realpath_size) {
     // Perform a PATH search if there's no slash in the path.
-    if (strchr(path_, '/') == nullptr) {
+    if (Namespace::IsDefault(namespc_) || strchr(path_, '/') == nullptr) {
       // TODO(zra): If there is a non-default namespace, the entries in PATH
       // should be treated as relative to the namespace.
       strncpy(realpath, path_, realpath_size);

runtime/bin/process_linux.cc

@@ -452,7 +452,7 @@ class ProcessStarter {
   // be reported to the parent.
   bool FindPathInNamespace(char* realpath, intptr_t realpath_size) {
     // Perform a PATH search if there's no slash in the path.
-    if (strchr(path_, '/') == nullptr) {
+    if (Namespace::IsDefault(namespc_) || strchr(path_, '/') == nullptr) {
       // TODO(zra): If there is a non-default namespace, the entries in PATH
       // should be treated as relative to the namespace.
       strncpy(realpath, path_, realpath_size);

tests/standalone/io/regress_54516_test.dart

@@ -0,0 +1,24 @@
+// Copyright (c) 2024, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'dart:io';
+
+import 'package:expect/expect.dart';
+
+Future<void> main() async {
+  // Create a shell script that prints the output.
+  final origDir = Directory.current;
+  final fileName = "tests/standalone/io/regress_54516_test.sh";
+  var script = new File("tests/standalone/io/regress_54516_test.sh");
+  if (!script.existsSync()) {
+    script = new File("../tests/standalone/io/regress_54516_test.sh");
+  }
+  var expectedResult = fileName + Platform.lineTerminator;
+  Expect.isTrue(script.existsSync());
+  List<String> args = [];
+  var result = Process.runSync(script.path, args, runInShell: false);
+  Expect.stringEquals(result.stdout, expectedResult);
+  result = Process.runSync(script.path, args, runInShell: true);
+  Expect.stringEquals(result.stdout, expectedResult);
+}

tests/standalone/io/regress_54516_test.sh

@@ -0,0 +1,4 @@
+#!/bin/bash
+#
+
+echo $0

tests/standalone/standalone_vm.status

@@ -41,6 +41,7 @@ io/socket_upgrade_to_secure_test: Skip # Issue 27638
 
 [ $system == windows ]
 io/process_sync_test: Pass, Timeout # Issue 24596
+io/regress_54516_test: SkipByDesign # Test uses a shell script which won't run on windows
 io/sleep_test: Pass, Fail # Issue 25757
 verbose_gc_to_bmu_test: Skip