1 /*
2 * Copyright (C) 2018 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 "android_os_NativeHandle.h"
18
19 #include <nativehelper/JNIHelp.h>
20 #include <nativehelper/ScopedLocalRef.h>
21
22 #include "core_jni_helpers.h"
23
24 #define PACKAGE_PATH "android/os"
25 #define CLASS_NAME "NativeHandle"
26 #define CLASS_PATH PACKAGE_PATH "/" CLASS_NAME
27
28 namespace android {
29
30 static struct {
31 jclass clazz;
32 jmethodID constructID; // NativeHandle(int[] fds, int[] ints, boolean owns)
33
34 jmethodID getFdsID; // int[] NativeHandle.getFds()
35 jmethodID getIntsID; // int[] NativeHandle.getInts()
36 } gNativeHandleFields;
37
MakeJavaNativeHandleObj(JNIEnv * env,const native_handle_t * handle)38 jobject JNativeHandle::MakeJavaNativeHandleObj(
39 JNIEnv *env, const native_handle_t *handle) {
40 if (handle == nullptr) { return nullptr; }
41
42 const int numFds = handle->numFds;
43 ScopedLocalRef<jintArray> fds(env, env->NewIntArray(numFds));
44 env->SetIntArrayRegion(fds.get(), 0, numFds, &(handle->data[0]));
45
46 const int numInts = handle->numInts;
47 ScopedLocalRef<jintArray> ints(env, env->NewIntArray(numInts));
48 env->SetIntArrayRegion(ints.get(), 0, numInts, &(handle->data[numFds]));
49
50 return env->NewObject(gNativeHandleFields.clazz,
51 gNativeHandleFields.constructID, fds.get(), ints.get(), false /*own*/);
52 }
53
MakeCppNativeHandle(JNIEnv * env,jobject jHandle,EphemeralStorage * storage)54 native_handle_t *JNativeHandle::MakeCppNativeHandle(
55 JNIEnv *env, jobject jHandle, EphemeralStorage *storage) {
56 if (jHandle == nullptr) { return nullptr; }
57
58 if (!env->IsInstanceOf(jHandle, gNativeHandleFields.clazz)) {
59 jniThrowException(env, "java/lang/ClassCastException",
60 "jHandle must be an instance of NativeHandle.");
61 return nullptr;
62 }
63
64 ScopedLocalRef<jintArray> fds(env, (jintArray) env->CallObjectMethod(
65 jHandle, gNativeHandleFields.getFdsID));
66
67 ScopedLocalRef<jintArray> ints(env, (jintArray) env->CallObjectMethod(
68 jHandle, gNativeHandleFields.getIntsID));
69
70 const int numFds = (int) env->GetArrayLength(fds.get());
71 const int numInts = (int) env->GetArrayLength(ints.get());
72
73 native_handle_t *handle = (storage == nullptr)
74 ? native_handle_create(numFds, numInts)
75 : storage->allocTemporaryNativeHandle(numFds, numInts);
76
77 if (handle != nullptr) {
78 env->GetIntArrayRegion(fds.get(), 0, numFds, &(handle->data[0]));
79 env->GetIntArrayRegion(ints.get(), 0, numInts, &(handle->data[numFds]));
80 } else {
81 jniThrowException(env, "java/lang/OutOfMemoryError",
82 "Failed to allocate memory for native_handle_t.");
83 }
84
85 return handle;
86 }
87
AllocJavaNativeHandleObjArray(JNIEnv * env,jsize length)88 jobjectArray JNativeHandle::AllocJavaNativeHandleObjArray(JNIEnv *env, jsize length) {
89 return env->NewObjectArray(length, gNativeHandleFields.clazz, nullptr);
90 }
91
register_android_os_NativeHandle(JNIEnv * env)92 int register_android_os_NativeHandle(JNIEnv *env) {
93 jclass clazz = FindClassOrDie(env, CLASS_PATH);
94 gNativeHandleFields.clazz = MakeGlobalRefOrDie(env, clazz);
95
96 gNativeHandleFields.constructID = GetMethodIDOrDie(env, clazz, "<init>", "([I[IZ)V");
97 gNativeHandleFields.getFdsID = GetMethodIDOrDie(env, clazz, "getFdsAsIntArray", "()[I");
98 gNativeHandleFields.getIntsID = GetMethodIDOrDie(env, clazz, "getInts", "()[I");
99
100 return 0;
101 }
102
103 }
104