/* Regression test for thread-safe reference-counting
 *
 * Author: Simon McVittie <simon.mcvittie@collabora.co.uk>
 * Copyright © 2011 Nokia Corporation
 * SPDX-License-Identifier: MIT
 *
 * Permission is hereby granted, free of charge, to any person
 * obtaining a copy of this software and associated documentation files
 * (the "Software"), to deal in the Software without restriction,
 * including without limitation the rights to use, copy, modify, merge,
 * publish, distribute, sublicense, and/or sell copies of the Software,
 * and to permit persons to whom the Software is furnished to do so,
 * subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be
 * included in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

#include <config.h>

#include <glib.h>
#include <glib-object.h>

#include <dbus/dbus.h>
#include <dbus/dbus-connection-internal.h>
#include <dbus/dbus-mainloop.h>
#include <dbus/dbus-message-internal.h>
#include <dbus/dbus-pending-call-internal.h>
#include <dbus/dbus-server-protected.h>
#include "test-utils-glib.h"

static void
assert_no_error (const DBusError *e)
{
  if (G_UNLIKELY (dbus_error_is_set (e)))
    g_error ("expected success but got error: %s: %s", e->name, e->message);
}

#define N_THREADS 200
#define N_REFS 10000
G_STATIC_ASSERT (((unsigned) N_THREADS * (unsigned) N_REFS) < G_MAXINT32);

static dbus_int32_t connection_slot = -1;
static dbus_int32_t server_slot = -1;
static dbus_int32_t message_slot = -1;
static dbus_int32_t pending_call_slot = -1;

typedef struct {
  DBusError e;
  DBusLoop *loop;
  DBusServer *server;
  DBusConnection *connection;
  DBusConnection *server_connection;
  DBusMessage *message;
  GThread *threads[N_THREADS];
  gboolean last_unref;
  unsigned n_refs;
  unsigned n_threads;
} Fixture;

typedef void *(*RefFunc) (void *);
typedef void (*VoidFunc) (void *);

typedef struct {
  const Fixture *f;
  void *thing;
  RefFunc ref;
  VoidFunc ref_void;
  VoidFunc unref;
  void *mutex;
  VoidFunc lock;
  VoidFunc unlock;
} Thread;

static gpointer
ref_thread (gpointer data)
{
  Thread *thread = data;
  const Fixture *f = thread->f;
  unsigned i;

  for (i = 0; i < f->n_refs; i++)
    {
      if (thread->lock != NULL)
        (thread->lock) (thread->mutex);

      if (thread->ref != NULL)
        {
          gpointer ret = (thread->ref) (thread->thing);

          g_assert (ret == thread->thing);
        }
      else
        {
          (thread->ref_void) (thread->thing);
        }

      if (thread->unlock != NULL)
        (thread->unlock) (thread->mutex);
    }

  return NULL;
}

static gpointer
cycle_thread (gpointer data)
{
  Thread *thread = data;
  const Fixture *f = thread->f;
  unsigned i;

  for (i = 0; i < f->n_refs; i++)
    {
      if (thread->lock != NULL)
        (thread->lock) (thread->mutex);

      if (thread->ref != NULL)
        {
          gpointer ret = (thread->ref) (thread->thing);

          g_assert (ret == thread->thing);
        }
      else
        {
          (thread->ref_void) (thread->thing);
        }

      (thread->unref) (thread->thing);

      if (thread->unlock != NULL)
        (thread->unlock) (thread->mutex);
    }

  return NULL;
}

static gpointer
unref_thread (gpointer data)
{
  Thread *thread = data;
  const Fixture *f = thread->f;
  unsigned i;

  for (i = 0; i < f->n_refs; i++)
    {
      if (thread->lock != NULL)
        (thread->lock) (thread->mutex);

      (thread->unref) (thread->thing);

      if (thread->unlock != NULL)
        (thread->unlock) (thread->mutex);
    }

  return NULL;
}

static void
last_unref (void *data)
{
  Fixture *f = data;

  g_assert (!f->last_unref);
  f->last_unref = TRUE;
}

static void
wait_for_all_threads (Fixture *f)
{
  unsigned i;

  for (i = 0; i < f->n_threads; i++)
    g_thread_join (f->threads[i]);
}

static void
new_conn_cb (DBusServer *server,
    DBusConnection *server_connection,
    void *data)
{
  Fixture *f = data;

  g_assert (f->server_connection == NULL);
  f->server_connection = dbus_connection_ref (server_connection);

  test_connection_setup (f->loop, f->server_connection);
}

static void
setup (Fixture *f,
    gconstpointer data)
{
#ifdef DBUS_WIN
  const char *dbus_test_slow = NULL;
#endif
  if (!dbus_threads_init_default ())
    g_error ("OOM");

  /* This can be fairly slow, so make the test timeout per-test */
  test_timeout_reset (1);

  f->n_threads = N_THREADS;
  f->n_refs = N_REFS;

#ifdef DBUS_WIN
  dbus_test_slow = g_getenv ("DBUS_TEST_SLOW");

  if (dbus_test_slow == NULL || atoi (dbus_test_slow) < 1)
    {
      /* Our reference-counting is really slow under Wine (it involves
       * IPC to wineserver) or Windows 7 guest on VirtualBox (5.22).
       * Do fewer iterations:  enough to demonstrate that it works,
       * rather than seriously trying to reproduce race conditions.
       */
      f->n_threads = 100;
      f->n_refs = 1000;
      g_info ("reducing number of threads/refs to %d/%d", f->n_threads, f->n_refs);
    }
#endif
  f->loop = _dbus_loop_new ();
  g_assert (f->loop != NULL);

  dbus_error_init (&f->e);

#ifdef DBUS_UNIX
  f->server = dbus_server_listen ("unix:tmpdir=/tmp", &f->e);
#else
  f->server = dbus_server_listen ("tcp:host=127.0.0.1", &f->e);
#endif

  assert_no_error (&f->e);
  g_assert (f->server != NULL);

  if (!dbus_connection_allocate_data_slot (&connection_slot))
    g_error ("OOM");

  if (!dbus_server_allocate_data_slot (&server_slot))
    g_error ("OOM");

  if (!dbus_message_allocate_data_slot (&message_slot))
    g_error ("OOM");

  if (!dbus_pending_call_allocate_data_slot (&pending_call_slot))
    g_error ("OOM");
}

static void
setup_connection (Fixture *f,
    gconstpointer data)
{
  char *address;

  setup (f, data);

  dbus_server_set_new_connection_function (f->server,
      new_conn_cb, f, NULL);

  test_server_setup (f->loop, f->server);

  address = dbus_server_get_address (f->server);
  g_assert (address != NULL);
  f->connection = dbus_connection_open_private (address, &f->e);
  assert_no_error (&f->e);
  g_assert (f->connection != NULL);
  dbus_free (address);

  test_connection_setup (f->loop, f->connection);

  while (f->server_connection == NULL)
    _dbus_loop_iterate (f->loop, TRUE);

  test_connection_shutdown (f->loop, f->connection);
  test_server_shutdown (f->loop, f->server);
}

static void
test_connection (Fixture *f,
    gconstpointer data)
{
  Thread public_api = {
    f,
    f->connection,
    (RefFunc) dbus_connection_ref,
    NULL,
    (VoidFunc) dbus_connection_unref,
    NULL,
    NULL,
    NULL };
  Thread internal_api = {
    f,
    f->connection,
    (RefFunc) _dbus_connection_ref_unlocked,
    NULL,
    (VoidFunc) _dbus_connection_unref_unlocked,
    f->connection,
    (VoidFunc) _dbus_connection_lock,
    (VoidFunc) _dbus_connection_unlock };
  unsigned i;

  /* Use a slot as a pseudo-weakref */
  if (!dbus_connection_set_data (f->connection, connection_slot, f,
        last_unref))
    g_error ("OOM");

  for (i = 0; i < f->n_threads; i++)
    {
      if ((i % 2) == 0)
        f->threads[i] = g_thread_new (NULL, ref_thread, &public_api);
      else
        f->threads[i] = g_thread_new (NULL, ref_thread, &internal_api);

      g_assert (f->threads[i] != NULL);
    }

  wait_for_all_threads (f);

  for (i = 0; i < f->n_threads; i++)
    {
      if ((i % 2) == 0)
        f->threads[i] = g_thread_new (NULL, cycle_thread, &public_api);
      else
        f->threads[i] = g_thread_new (NULL, cycle_thread, &internal_api);

      g_assert (f->threads[i] != NULL);
    }

  wait_for_all_threads (f);

  for (i = 0; i < f->n_threads; i++)
    {
      if ((i % 2) == 0)
        f->threads[i] = g_thread_new (NULL, unref_thread, &public_api);
      else
        f->threads[i] = g_thread_new (NULL, unref_thread, &internal_api);

      g_assert (f->threads[i] != NULL);
    }

  wait_for_all_threads (f);

  /* Destroy the connection. This should be the last-unref. */
  g_assert (!f->last_unref);
  test_connection_shutdown (f->loop, f->connection);
  dbus_connection_close (f->connection);
  dbus_connection_unref (f->connection);
  f->connection = NULL;
  g_assert (f->last_unref);
}

static void
server_lock (void *server)
{
  SERVER_LOCK (((DBusServer *) server));
}

static void
server_unlock (void *server)
{
  SERVER_UNLOCK (((DBusServer *) server));
}

static void
test_server (Fixture *f,
    gconstpointer data)
{
  Thread public_api = {
    f,
    f->server,
    (RefFunc) dbus_server_ref,
    NULL,
    (VoidFunc) dbus_server_unref,
    NULL,
    NULL,
    NULL };
  Thread internal_api = {
    f,
    f->server,
    NULL,
    (VoidFunc) _dbus_server_ref_unlocked,
    (VoidFunc) _dbus_server_unref_unlocked,
    f->server,
    server_lock,
    server_unlock };
  unsigned i;

  if (!dbus_server_set_data (f->server, server_slot, f, last_unref))
    g_error ("OOM");

  for (i = 0; i < f->n_threads; i++)
    {
      if ((i % 2) == 0)
        f->threads[i] = g_thread_new (NULL, ref_thread, &public_api);
      else
        f->threads[i] = g_thread_new (NULL, ref_thread, &internal_api);

      g_assert (f->threads[i] != NULL);
    }

  wait_for_all_threads (f);

  for (i = 0; i < f->n_threads; i++)
    {
      if ((i % 2) == 0)
        f->threads[i] = g_thread_new (NULL, cycle_thread, &public_api);
      else
        f->threads[i] = g_thread_new (NULL, cycle_thread, &internal_api);

      g_assert (f->threads[i] != NULL);
    }

  wait_for_all_threads (f);

  for (i = 0; i < f->n_threads; i++)
    {
      if ((i % 2) == 0)
        f->threads[i] = g_thread_new (NULL, unref_thread, &public_api);
      else
        f->threads[i] = g_thread_new (NULL, unref_thread, &internal_api);

      g_assert (f->threads[i] != NULL);
    }

  wait_for_all_threads (f);

  /* Destroy the server. This should be the last-unref. */
  g_assert (!f->last_unref);
  test_server_shutdown (f->loop, f->server);
  dbus_server_unref (f->server);
  f->server = NULL;
  g_assert (f->last_unref);
}

static void
test_message (Fixture *f,
    gconstpointer data)
{
  DBusMessage *message = dbus_message_new_signal ("/foo", "foo.bar.baz",
      "Foo");
  Thread public_api = {
    f,
    message,
    (RefFunc) dbus_message_ref,
    NULL,
    (VoidFunc) dbus_message_unref,
    NULL,
    NULL,
    NULL };
  unsigned i;

  if (!dbus_message_set_data (message, message_slot, f, last_unref))
    g_error ("OOM");

  for (i = 0; i < f->n_threads; i++)
    {
      f->threads[i] = g_thread_new (NULL, ref_thread, &public_api);
      g_assert (f->threads[i] != NULL);
    }

  wait_for_all_threads (f);

  for (i = 0; i < f->n_threads; i++)
    {
      f->threads[i] = g_thread_new (NULL, cycle_thread, &public_api);
      g_assert (f->threads[i] != NULL);
    }

  wait_for_all_threads (f);

  for (i = 0; i < f->n_threads; i++)
    {
      f->threads[i] = g_thread_new (NULL, unref_thread, &public_api);
      g_assert (f->threads[i] != NULL);
    }

  wait_for_all_threads (f);

  /* Destroy the server. This should be the last-unref. */
  g_assert (!f->last_unref);
  dbus_message_unref (message);
  g_assert (f->last_unref);
}

static void
test_pending_call (Fixture *f,
    gconstpointer data)
{
  Thread public_api = {
    f,
    NULL,
    (RefFunc) dbus_pending_call_ref,
    NULL,
    (VoidFunc) dbus_pending_call_unref,
    NULL,
    NULL,
    NULL };
  Thread internal_api = {
    f,
    NULL,
    (RefFunc) _dbus_pending_call_ref_unlocked,
    NULL,
    (VoidFunc) dbus_pending_call_unref,
    f->connection,
    (VoidFunc) _dbus_connection_lock,
    (VoidFunc) _dbus_connection_unlock };
  /* This one can't be used to ref, only to cycle or unref. */
  Thread unref_and_unlock_api = {
    f,
    NULL,
    (RefFunc) _dbus_pending_call_ref_unlocked,
    NULL,
    (VoidFunc) _dbus_pending_call_unref_and_unlock,
    f->connection,
    (VoidFunc) _dbus_connection_lock,
    NULL };
  unsigned i;
  DBusPendingCall *pending_call;

  _dbus_connection_lock (f->connection);
  pending_call = _dbus_pending_call_new_unlocked (f->connection,
      DBUS_TIMEOUT_INFINITE, NULL);
  g_assert (pending_call != NULL);
  _dbus_connection_unlock (f->connection);

  public_api.thing = pending_call;
  internal_api.thing = pending_call;
  unref_and_unlock_api.thing = pending_call;

  if (!dbus_pending_call_set_data (pending_call, pending_call_slot, f,
        last_unref))
    g_error ("OOM");

  for (i = 0; i < f->n_threads; i++)
    {
      if ((i % 2) == 0)
        f->threads[i] = g_thread_new (NULL, ref_thread, &public_api);
      else
        f->threads[i] = g_thread_new (NULL, ref_thread, &internal_api);

      g_assert (f->threads[i] != NULL);
    }

  wait_for_all_threads (f);

  for (i = 0; i < f->n_threads; i++)
    {
      switch (i % 3)
        {
          case 0:
            f->threads[i] = g_thread_new (NULL, cycle_thread, &public_api);
            break;
          case 1:
            f->threads[i] = g_thread_new (NULL, cycle_thread, &internal_api);
            break;
          default:
            f->threads[i] = g_thread_new (NULL, cycle_thread,
                &unref_and_unlock_api);
        }

      g_assert (f->threads[i] != NULL);
    }

  wait_for_all_threads (f);

  for (i = 0; i < f->n_threads; i++)
    {
      switch (i % 3)
        {
          case 0:
            f->threads[i] = g_thread_new (NULL, unref_thread, &public_api);
            break;
          case 1:
            f->threads[i] = g_thread_new (NULL, unref_thread, &internal_api);
            break;
          default:
            f->threads[i] = g_thread_new (NULL, unref_thread,
                &unref_and_unlock_api);
        }

      g_assert (f->threads[i] != NULL);
    }

  wait_for_all_threads (f);

  /* Destroy the pending call. This should be the last-unref. */
  g_assert (!f->last_unref);
  dbus_pending_call_unref (pending_call);
  g_assert (f->last_unref);
}

static void
teardown (Fixture *f,
    gconstpointer data)
{
  if (f->server_connection != NULL)
    {
      test_connection_shutdown (f->loop, f->server_connection);
      dbus_connection_close (f->server_connection);
      dbus_connection_unref (f->server_connection);
    }

  if (f->connection != NULL)
    {
      test_connection_shutdown (f->loop, f->connection);
      dbus_connection_close (f->connection);
      dbus_connection_unref (f->connection);
    }

  if (f->server != NULL)
    {
      dbus_server_disconnect (f->server);
      dbus_server_unref (f->server);
    }

  dbus_connection_free_data_slot (&connection_slot);
  dbus_server_free_data_slot (&server_slot);
  dbus_message_free_data_slot (&message_slot);
  dbus_pending_call_free_data_slot (&pending_call_slot);

  _dbus_loop_unref (f->loop);
  dbus_error_free (&f->e);
}

int
main (int argc,
    char **argv)
{
  int ret;

  test_init (&argc, &argv);

  g_test_add ("/refs/connection", Fixture, NULL, setup_connection,
      test_connection, teardown);
  g_test_add ("/refs/message", Fixture, NULL, setup,
      test_message, teardown);
  g_test_add ("/refs/pending-call", Fixture, NULL, setup_connection,
      test_pending_call, teardown);
  g_test_add ("/refs/server", Fixture, NULL, setup,
      test_server, teardown);

  ret = g_test_run ();
  dbus_shutdown ();
  return ret;
}