1/*
2 * Copyright (C) 2013 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#include <errno.h>
18#include <fcntl.h>
19
20#include <gtest/gtest.h>
21
22#if defined(__BIONIC__) // Android's prebuilt gcc's header files don't include <sys/eventfd.h>.
23#include <sys/eventfd.h>
24#else
25// Include the necessary components of sys/eventfd.h right here.
26#include <stdint.h>
27
28typedef uint64_t eventfd_t;
29
30__BEGIN_DECLS
31extern int eventfd(int, int);
32extern int eventfd_read(int, eventfd_t*);
33extern int eventfd_write(int, eventfd_t);
34__END_DECLS
35#endif
36
37TEST(eventfd, smoke) {
38  unsigned int initial_value = 2;
39  int fd = eventfd(initial_value, O_NONBLOCK);
40  ASSERT_NE(fd, -1);
41
42  eventfd_t value = 123;
43  ASSERT_EQ(0, eventfd_read(fd, &value));
44  ASSERT_EQ(initial_value, value);
45
46  // Reading clears the counter.
47  ASSERT_EQ(-1, eventfd_read(fd, &value));
48  ASSERT_EQ(EAGAIN, errno);
49
50  // Values written are added until the next read.
51  ASSERT_EQ(0, eventfd_write(fd, 1));
52  ASSERT_EQ(0, eventfd_write(fd, 1));
53  ASSERT_EQ(0, eventfd_write(fd, 1));
54
55  ASSERT_EQ(0, eventfd_read(fd, &value));
56  ASSERT_EQ(3U, value);
57
58  close(fd);
59}
60