zircon/system/ulib/sync/condition.cc

// Copyright 2018 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include <assert.h>
#include <lib/sync/condition.h>
#include <lib/sync/internal/condition-template.h>
#include <zircon/compiler.h>

template <>
struct condition_impl_internal::MutexOps<sync_mutex_t> {
  static zx_futex_t* get_futex(sync_mutex_t* mutex) { return &mutex->futex; }

  static zx_status_t lock(sync_mutex_t* mutex, int* mutex_lock_err) __TA_ACQUIRE(mutex) {
    sync_mutex_lock(mutex);
    return ZX_OK;
  }

  static zx_status_t lock_with_waiters(sync_mutex_t* mutex, int waiters_delta, int* mutex_lock_err)
      __TA_ACQUIRE(mutex) {
    sync_mutex_lock_with_waiter(mutex);
    return ZX_OK;
  }

  static void unlock(sync_mutex_t* mutex) __TA_RELEASE(mutex) { sync_mutex_unlock(mutex); }

  static void signal_requeue(sync_completion_t* completion, sync_mutex_t* mutex) {
    zx_futex_storage_t mutex_val = __atomic_load_n(&mutex->futex, __ATOMIC_ACQUIRE);
    sync_completion_signal_requeue(completion, &mutex->futex,
                                   libsync_mutex_make_owner_from_state(mutex_val));
  }
};

void sync_condition_wait(sync_condition_t* condition, sync_mutex_t* mutex) {
  [[maybe_unused]] zx_status_t status =
      condition_impl_internal::timedwait(condition, mutex, ZX_TIME_INFINITE, nullptr);
  assert(status == ZX_OK);
}

zx_status_t sync_condition_timedwait(sync_condition_t* condition, sync_mutex_t* mutex,
                                     zx_time_t deadline) {
  return condition_impl_internal::timedwait(condition, mutex, deadline, nullptr);
}

void sync_condition_signal(sync_condition_t* condition) {
  return condition_impl_internal::signal(condition, 1);
}

void sync_condition_broadcast(sync_condition_t* condition) {
  condition_impl_internal::signal(condition, -1);
}