1 /*
2 * Copyright (C) 2008 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
18 /*
19 * System clock functions.
20 */
21
22 #include <sys/time.h>
23 #include <limits.h>
24 #include <fcntl.h>
25 #include <errno.h>
26 #include <string.h>
27
28 #include <nativehelper/JNIHelp.h>
29 #include "jni.h"
30 #include "core_jni_helpers.h"
31
32 #include <utils/SystemClock.h>
33 #include <utils/Timers.h>
34
35 namespace android {
36
37 static_assert(std::is_same<int64_t, jlong>::value, "jlong isn't an int64_t");
38 static_assert(std::is_same<decltype(uptimeMillis()), int64_t>::value,
39 "uptimeMillis signature change, expected int64_t return value");
40 static_assert(std::is_same<decltype(elapsedRealtime()), int64_t>::value,
41 "uptimeMillis signature change, expected int64_t return value");
42 static_assert(std::is_same<decltype(elapsedRealtimeNano()), int64_t>::value,
43 "uptimeMillis signature change, expected int64_t return value");
44
45 /*
46 * native public static long currentThreadTimeMillis();
47 */
android_os_SystemClock_currentThreadTimeMillis()48 static jlong android_os_SystemClock_currentThreadTimeMillis()
49 {
50 return nanoseconds_to_milliseconds(systemTime(SYSTEM_TIME_THREAD));
51 }
52
53 /*
54 * native public static long currentThreadTimeMicro();
55 */
android_os_SystemClock_currentThreadTimeMicro()56 static jlong android_os_SystemClock_currentThreadTimeMicro()
57 {
58 return nanoseconds_to_microseconds(systemTime(SYSTEM_TIME_THREAD));
59 }
60
61 /*
62 * native public static long currentTimeMicro();
63 */
android_os_SystemClock_currentTimeMicro()64 static jlong android_os_SystemClock_currentTimeMicro()
65 {
66 struct timeval tv;
67
68 gettimeofday(&tv, NULL);
69 return tv.tv_sec * 1000000LL + tv.tv_usec;
70 }
71
72 /*
73 * JNI registration.
74 */
75 static const JNINativeMethod gMethods[] = {
76 // All of these are @CriticalNative, so we can defer directly to SystemClock.h for
77 // some of these
78 { "uptimeMillis", "()J", (void*) uptimeMillis },
79 { "elapsedRealtime", "()J", (void*) elapsedRealtime },
80 { "elapsedRealtimeNanos", "()J", (void*) elapsedRealtimeNano },
81
82 // SystemClock doesn't have an implementation for these that we can directly call
83 { "currentThreadTimeMillis", "()J",
84 (void*) android_os_SystemClock_currentThreadTimeMillis },
85 { "currentThreadTimeMicro", "()J",
86 (void*) android_os_SystemClock_currentThreadTimeMicro },
87 { "currentTimeMicro", "()J",
88 (void*) android_os_SystemClock_currentTimeMicro },
89 };
register_android_os_SystemClock(JNIEnv * env)90 int register_android_os_SystemClock(JNIEnv* env)
91 {
92 return RegisterMethodsOrDie(env, "android/os/SystemClock", gMethods, NELEM(gMethods));
93 }
94
95 }; // namespace android
96
97