LibCore: Add rmdir system call wrapper

Author: https://github.com/ldm5180
Commit: https://github.com/SerenityOS/serenity/commit/b455363ce7
Pull-request: https://github.com/SerenityOS/serenity/pull/12421
Reviewed-by: https://github.com/timschumi

Userland/Libraries/LibCore/System.cpp

@@ -766,6 +766,21 @@ ErrorOr<void> chdir(StringView path)
 #endif
 }
 
+ErrorOr<void> rmdir(StringView path)
+{
+    if (path.is_null())
+        return Error::from_errno(EFAULT);
+#ifdef __serenity__
+    int rc = syscall(SC_rmdir, path.characters_without_null_termination(), path.length());
+    HANDLE_SYSCALL_RETURN_VALUE("rmdir"sv, rc, {});
+#else
+    String path_string = path;
+    if (::rmdir(path_string.characters()) < 0)
+        return Error::from_syscall("rmdir"sv, -errno);
+    return {};
+#endif
+}
+
 ErrorOr<pid_t> fork()
 {
     pid_t pid = ::fork();

Userland/Libraries/LibCore/System.h

@@ -111,6 +111,7 @@ ErrorOr<bool> isatty(int fd);
 ErrorOr<void> symlink(StringView target, StringView link_path);
 ErrorOr<void> mkdir(StringView path, mode_t);
 ErrorOr<void> chdir(StringView path);
+ErrorOr<void> rmdir(StringView path);
 ErrorOr<pid_t> fork();
 ErrorOr<int> mkstemp(Span<char> pattern);
 ErrorOr<void> fchmod(int fd, mode_t mode);
@@ -142,5 +143,4 @@ ErrorOr<void> socketpair(int domain, int type, int protocol, int sv[2]);
 ErrorOr<Vector<gid_t>> getgroups();
 ErrorOr<void> mknod(StringView pathname, mode_t mode, dev_t dev);
 ErrorOr<void> mkfifo(StringView pathname, mode_t mode);
-
 }