[NODERAWFS] Fix getcwd() on Windows

system/lib/libc/musl/src/unistd/getcwd.c

@@ -17,7 +17,18 @@ char *getcwd(char *buf, size_t size)
 	long ret = syscall(SYS_getcwd, buf, size);
 	if (ret < 0)
 		return 0;
+#ifdef __EMSCRIPTEN__
+	// In upstream musl, `buf[0] != '/'` checks for Linux's `(unreachable)`
+	// prefix returned by the kernel's getcwd syscall. Emscripten's
+	// __syscall_getcwd never returns `(unreachable)` (it returns -ENOENT
+	// directly), and under NODERAWFS on Windows valid paths can start with
+	// a drive letter (e.g. `C:\...`) or UNC prefix (`\\...`). That is, the
+	// Emscripten change here is to get musl to work properly on Windows (which
+	// musl does not normally do).
+	if (ret == 0) {
+#else
 	if (ret == 0 || buf[0] != '/') {
+#endif
 		errno = ENOENT;
 		return 0;
 	}

test/codesize/test_codesize_hello_dylink_all.json

@@ -1,7 +1,7 @@
 {
   "a.out.js": 270695,
-  "a.out.nodebug.wasm": 588110,
-  "total": 858805,
+  "a.out.nodebug.wasm": 588098,
+  "total": 858793,
   "sent": [
     "IMG_Init",
     "IMG_Load",

test/test_other.py

@@ -9753,6 +9753,7 @@ def test_noderawfs_disables_embedding(self):
     self.assert_fail(base + ['--preload-file', 'somefile'], expected)
     self.assert_fail(base + ['--embed-file', 'somefile'], expected)
 
+  @crossplatform
   def test_noderawfs_access_abspath(self):
     create_file('foo', 'bar')
     create_file('access.c', r'''
@@ -9763,6 +9764,24 @@ def test_noderawfs_access_abspath(self):
     ''')
     self.do_runf('access.c', cflags=['-sNODERAWFS'], args=[os.path.abspath('foo')])
 
+  @crossplatform
+  def test_noderawfs_getcwd(self):
+    create_file('getcwd.c', r'''
+      #include <assert.h>
+      #include <limits.h>
+      #include <stdio.h>
+      #include <unistd.h>
+
+      int main() {
+        char buf[PATH_MAX];
+        char* cwd = getcwd(buf, sizeof(buf));
+        assert(cwd == buf);
+        printf("cwd: %s\n", cwd);
+        return 0;
+      }
+    ''')
+    self.do_runf('getcwd.c', f'cwd: {os.getcwd()}\n', cflags=['-sNODERAWFS'])
+
   def test_noderawfs_readfile_prerun(self):
     create_file('foo', 'bar')
     self.add_pre_run("console.log(FS.readFile('foo', { encoding: 'utf8' }));")

test/unistd/unlink.c

@@ -140,7 +140,8 @@ void test() {
   // Update: Removing cwd on Linux does not return EBUSY.
   // WASMFS behaviour will match the native FS.
 #ifndef __APPLE__
-  getcwd(buffer, sizeof(buffer));
+  char* cwd = getcwd(buffer, sizeof(buffer));
+  assert(cwd != NULL);
   printf("CWD: %s\n", buffer);
   err = rmdir(buffer);
   assert(err == -1);