setjmp method

int setjmp(jmp_buf env, void body())

Dart-specific adaptation of C's setjmp.

Since Dart does not support returning twice from a function, this adaptation takes a closure. It executes body synchronously.

Returns 0 if body completes normally, or the integer value provided to longjmp if a non-local jump occurred targeting the provided env.

Implementation

int setjmp(jmp_buf env, void Function() body) {
  try {
    body();
    return 0;
  } on LongJmpException catch (e) {
    if (e.env == env) {
      return e.val == 0 ? 1 : e.val;
    }
    rethrow; // It was meant for a different jmp_buf
  }
}