Handle/ignore AT_NO_AUTOMOUNT in fstatat (#18261)

Fixes: #17660

Author: sbc100

src/library_syscall.js

@@ -861,9 +861,9 @@ var SyscallsLibrary = {
     path = SYSCALLS.getStr(path);
     var nofollow = flags & {{{ cDefine('AT_SYMLINK_NOFOLLOW') }}};
     var allowEmpty = flags & {{{ cDefine('AT_EMPTY_PATH') }}};
-    flags = flags & (~{{{ cDefine('AT_SYMLINK_NOFOLLOW') | cDefine('AT_EMPTY_PATH') }}});
+    flags = flags & (~{{{ cDefine('AT_SYMLINK_NOFOLLOW') | cDefine('AT_EMPTY_PATH') | cDefine('AT_NO_AUTOMOUNT') }}});
 #if ASSERTIONS
-    assert(!flags, flags);
+    assert(!flags, 'unknown flags in __syscall_newfstatat: ' + flags);
 #endif
     path = SYSCALLS.calculateAt(dirfd, path, allowEmpty);
     return SYSCALLS.doStat(nofollow ? FS.lstat : FS.stat, path, buf);

src/struct_info.json

@@ -103,7 +103,8 @@
             "AT_FDCWD",
             "AT_SYMLINK_NOFOLLOW",
             "AT_REMOVEDIR",
-            "AT_EMPTY_PATH"
+            "AT_EMPTY_PATH",
+            "AT_NO_AUTOMOUNT"
         ],
         "structs": {
             "flock": [

test/reference_struct_info.json

@@ -34,6 +34,7 @@
         "AL_VELOCITY": 4102,
         "AT_EMPTY_PATH": 4096,
         "AT_FDCWD": -100,
+        "AT_NO_AUTOMOUNT": 2048,
         "AT_REMOVEDIR": 512,
         "AT_SYMLINK_NOFOLLOW": 256,
         "AUDIO_F32": 33056,

test/stat/test_fstatat.c

@@ -146,8 +146,9 @@ void test() {
   close(fd);
 
   // lstat a link - with AT_FDCWD and AT_SYMLINK_NOFOLLOW.
+  // Also test that AT_NO_AUTOMOUNT is ignored.
   memset(&s, 0, sizeof(s));
-  err = fstatat(AT_FDCWD, "folder/file-link", &s, AT_SYMLINK_NOFOLLOW);
+  err = fstatat(AT_FDCWD, "folder/file-link", &s, AT_SYMLINK_NOFOLLOW|AT_NO_AUTOMOUNT);
   assert(!err);
   assert(s.st_dev);
   assert(s.st_ino);