int GetStatusFileDescriptor()

in ext/gtest-1.8.0/googletest/src/gtest-death-test.cc [1227:1288]


int GetStatusFileDescriptor(unsigned int parent_process_id,
                            size_t write_handle_as_size_t,
                            size_t event_handle_as_size_t) {
  AutoHandle parent_process_handle(::OpenProcess(PROCESS_DUP_HANDLE,
                                                   FALSE,  // Non-inheritable.
                                                   parent_process_id));
  if (parent_process_handle.Get() == INVALID_HANDLE_VALUE) {
    DeathTestAbort("Unable to open parent process " +
                   StreamableToString(parent_process_id));
  }

  // TODO(vladl@google.com): Replace the following check with a
  // compile-time assertion when available.
  GTEST_CHECK_(sizeof(HANDLE) <= sizeof(size_t));

  const HANDLE write_handle =
      reinterpret_cast<HANDLE>(write_handle_as_size_t);
  HANDLE dup_write_handle;

  // The newly initialized handle is accessible only in in the parent
  // process. To obtain one accessible within the child, we need to use
  // DuplicateHandle.
  if (!::DuplicateHandle(parent_process_handle.Get(), write_handle,
                         ::GetCurrentProcess(), &dup_write_handle,
                         0x0,    // Requested privileges ignored since
                                 // DUPLICATE_SAME_ACCESS is used.
                         FALSE,  // Request non-inheritable handler.
                         DUPLICATE_SAME_ACCESS)) {
    DeathTestAbort("Unable to duplicate the pipe handle " +
                   StreamableToString(write_handle_as_size_t) +
                   " from the parent process " +
                   StreamableToString(parent_process_id));
  }

  const HANDLE event_handle = reinterpret_cast<HANDLE>(event_handle_as_size_t);
  HANDLE dup_event_handle;

  if (!::DuplicateHandle(parent_process_handle.Get(), event_handle,
                         ::GetCurrentProcess(), &dup_event_handle,
                         0x0,
                         FALSE,
                         DUPLICATE_SAME_ACCESS)) {
    DeathTestAbort("Unable to duplicate the event handle " +
                   StreamableToString(event_handle_as_size_t) +
                   " from the parent process " +
                   StreamableToString(parent_process_id));
  }

  const int write_fd =
      ::_open_osfhandle(reinterpret_cast<intptr_t>(dup_write_handle), O_APPEND);
  if (write_fd == -1) {
    DeathTestAbort("Unable to convert pipe handle " +
                   StreamableToString(write_handle_as_size_t) +
                   " to a file descriptor");
  }

  // Signals the parent that the write end of the pipe has been acquired
  // so the parent can release its own write end.
  ::SetEvent(dup_event_handle);

  return write_fd;
}