1 /*
2 * Copyright (C) 2023 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 #define LOG_NAMESPACE "TeX.tag."
18 #define LOG_TAG "TeX"
19
20 #include <log/log.h>
21 #include <nativehelper/scoped_local_ref.h>
22 #include <nativehelper/scoped_utf_chars.h>
23 #include <utils/hash/farmhash.h>
24
25 // ----------------------------------------------------------------------------
26 // JNI Glue
27 // ----------------------------------------------------------------------------
28
29 static jclass gStringClass = nullptr;
30
31 /**
32 * Class: com_android_modules_expresslog_Utils
33 * Method: hashString
34 * Signature: (Ljava/lang/String;)J
35 */
hashString(JNIEnv * env,jclass,jstring metricNameObj)36 static jlong hashString(JNIEnv* env, jclass /*class*/, jstring metricNameObj) {
37 ScopedUtfChars name(env, metricNameObj);
38 if (name.c_str() == nullptr) {
39 return 0;
40 }
41
42 return static_cast<jlong>(farmhash::Fingerprint64(name.c_str(), name.size()));
43 }
44
45 static const JNINativeMethod gMethods[] = {
46 {"hashString", "(Ljava/lang/String;)J", (void*)hashString},
47 };
48
49 namespace android {
50
register_com_android_modules_expresslog_Utils(JNIEnv * env)51 int register_com_android_modules_expresslog_Utils(JNIEnv* env) {
52 static const char* const kUtilsClassName = "com/android/modules/expresslog/Utils";
53 static const char* const kStringClassName = "java/lang/String";
54
55 ScopedLocalRef<jclass> utilsCls(env, env->FindClass(kUtilsClassName));
56 if (utilsCls.get() == nullptr) {
57 ALOGE("jni expresslog registration failure, class not found '%s'", kUtilsClassName);
58 return JNI_ERR;
59 }
60
61 jclass stringClass = env->FindClass(kStringClassName);
62 if (stringClass == nullptr) {
63 ALOGE("jni expresslog registration failure, class not found '%s'", kStringClassName);
64 return JNI_ERR;
65 }
66 gStringClass = static_cast<jclass>(env->NewGlobalRef(stringClass));
67 if (gStringClass == nullptr) {
68 ALOGE("jni expresslog Unable to create global reference '%s'", kStringClassName);
69 return JNI_ERR;
70 }
71
72 const jint count = sizeof(gMethods) / sizeof(gMethods[0]);
73 int status = env->RegisterNatives(utilsCls.get(), gMethods, count);
74 if (status < 0) {
75 ALOGE("jni expresslog registration failure, status: %d", status);
76 return JNI_ERR;
77 }
78 return JNI_VERSION_1_4;
79 }
80
81 } // namespace android
82