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/*
 * Copyright (C) 2010 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#ifndef SCOPEDPRIMITIVEARRAY_H_
#define SCOPEDPRIMITIVEARRAY_H_

#include <conscrypt/jniutil.h>

// ScopedBooleanArrayRO, ScopedByteArrayRO, ScopedCharArrayRO, ScopedDoubleArrayRO,
// ScopedFloatArrayRO, ScopedIntArrayRO, ScopedLongArrayRO, and ScopedShortArrayRO provide
// convenient read-only access to Java arrays from JNI code. This is cheaper than read-write
// access and should be used by default.
#define INSTANTIATE_SCOPED_PRIMITIVE_ARRAY_RO(PRIMITIVE_TYPE, NAME)                   \
    class Scoped##NAME##ArrayRO {                                                     \
     public:                                                                          \
        explicit Scoped##NAME##ArrayRO(JNIEnv* env)                                   \
            : mEnv(env), mJavaArray(nullptr), mRawArray(nullptr) {}                   \
        Scoped##NAME##ArrayRO(JNIEnv* env, PRIMITIVE_TYPE##Array javaArray)           \
            : mEnv(env), mJavaArray(javaArray), mRawArray(nullptr) {                  \
            if (mJavaArray == nullptr) {                                              \
                conscrypt::jniutil::throwNullPointerException(mEnv, nullptr);      \
            } else {                                                                  \
                mRawArray = mEnv->Get##NAME##ArrayElements(mJavaArray, nullptr);      \
            }                                                                         \
        }                                                                             \
        ~Scoped##NAME##ArrayRO() {                                                    \
            if (mRawArray) {                                                          \
                mEnv->Release##NAME##ArrayElements(mJavaArray, mRawArray, JNI_ABORT); \
            }                                                                         \
        }                                                                             \
        void reset(PRIMITIVE_TYPE##Array javaArray) {                                 \
            mJavaArray = javaArray;                                                   \
            mRawArray = mEnv->Get##NAME##ArrayElements(mJavaArray, nullptr);          \
        }                                                                             \
        const PRIMITIVE_TYPE* get() const {                                           \
            return mRawArray;                                                         \
        }                                                                             \
        PRIMITIVE_TYPE##Array getJavaArray() const {                                  \
            return mJavaArray;                                                        \
        }                                                                             \
        const PRIMITIVE_TYPE& operator[](size_t n) const {                            \
            return mRawArray[n];                                                      \
        }                                                                             \
        size_t size() const {                                                         \
            return static_cast<size_t>(mEnv->GetArrayLength(mJavaArray));             \
        }                                                                             \
                                                                                      \
     private:                                                                         \
        JNIEnv* mEnv;                                                                 \
        PRIMITIVE_TYPE##Array mJavaArray;                                             \
        PRIMITIVE_TYPE* mRawArray;                                                    \
        Scoped##NAME##ArrayRO(const Scoped##NAME##ArrayRO&);                          \
        void operator=(const Scoped##NAME##ArrayRO&);                                 \
    }

INSTANTIATE_SCOPED_PRIMITIVE_ARRAY_RO(jboolean, Boolean);
INSTANTIATE_SCOPED_PRIMITIVE_ARRAY_RO(jbyte, Byte);
INSTANTIATE_SCOPED_PRIMITIVE_ARRAY_RO(jchar, Char);
INSTANTIATE_SCOPED_PRIMITIVE_ARRAY_RO(jdouble, Double);
INSTANTIATE_SCOPED_PRIMITIVE_ARRAY_RO(jfloat, Float);
INSTANTIATE_SCOPED_PRIMITIVE_ARRAY_RO(jint, Int);
INSTANTIATE_SCOPED_PRIMITIVE_ARRAY_RO(jlong, Long);
INSTANTIATE_SCOPED_PRIMITIVE_ARRAY_RO(jshort, Short);

#undef INSTANTIATE_SCOPED_PRIMITIVE_ARRAY_RO

// ScopedBooleanArrayRW, ScopedByteArrayRW, ScopedCharArrayRW, ScopedDoubleArrayRW,
// ScopedFloatArrayRW, ScopedIntArrayRW, ScopedLongArrayRW, and ScopedShortArrayRW provide
// convenient read-write access to Java arrays from JNI code. These are more expensive,
// since they entail a copy back onto the Java heap, and should only be used when necessary.
#define INSTANTIATE_SCOPED_PRIMITIVE_ARRAY_RW(PRIMITIVE_TYPE, NAME)              \
    class Scoped##NAME##ArrayRW {                                                \
     public:                                                                      \
        explicit Scoped##NAME##ArrayRW(JNIEnv* env)                              \
            : mEnv(env), mJavaArray(nullptr), mRawArray(nullptr) {}              \
        Scoped##NAME##ArrayRW(JNIEnv* env, PRIMITIVE_TYPE##Array javaArray)      \
            : mEnv(env), mJavaArray(javaArray), mRawArray(nullptr) {             \
            if (mJavaArray == nullptr) {                                         \
                conscrypt::jniutil::throwNullPointerException(mEnv, nullptr); \
            } else {                                                             \
                mRawArray = mEnv->Get##NAME##ArrayElements(mJavaArray, nullptr); \
            }                                                                    \
        }                                                                        \
        ~Scoped##NAME##ArrayRW() {                                               \
            if (mRawArray) {                                                     \
                mEnv->Release##NAME##ArrayElements(mJavaArray, mRawArray, 0);    \
            }                                                                    \
        }                                                                        \
        void reset(PRIMITIVE_TYPE##Array javaArray) {                            \
            mJavaArray = javaArray;                                              \
            mRawArray = mEnv->Get##NAME##ArrayElements(mJavaArray, nullptr);     \
        }                                                                        \
        const PRIMITIVE_TYPE* get() const {                                      \
            return mRawArray;                                                    \
        }                                                                        \
        PRIMITIVE_TYPE##Array getJavaArray() const {                             \
            return mJavaArray;                                                   \
        }                                                                        \
        const PRIMITIVE_TYPE& operator[](size_t n) const {                       \
            return mRawArray[n];                                                 \
        }                                                                        \
        PRIMITIVE_TYPE* get() {                                                  \
            return mRawArray;                                                    \
        }                                                                        \
        PRIMITIVE_TYPE& operator[](size_t n) {                                   \
            return mRawArray[n];                                                 \
        }                                                                        \
        size_t size() const {                                                    \
            return static_cast<size_t>(mEnv->GetArrayLength(mJavaArray));        \
        }                                                                        \
                                                                                 \
     private:                                                                     \
        JNIEnv* mEnv;                                                            \
        PRIMITIVE_TYPE##Array mJavaArray;                                        \
        PRIMITIVE_TYPE* mRawArray;                                               \
        Scoped##NAME##ArrayRW(const Scoped##NAME##ArrayRW&);                     \
        void operator=(const Scoped##NAME##ArrayRW&);                            \
    }

INSTANTIATE_SCOPED_PRIMITIVE_ARRAY_RW(jboolean, Boolean);
INSTANTIATE_SCOPED_PRIMITIVE_ARRAY_RW(jbyte, Byte);
INSTANTIATE_SCOPED_PRIMITIVE_ARRAY_RW(jchar, Char);
INSTANTIATE_SCOPED_PRIMITIVE_ARRAY_RW(jdouble, Double);
INSTANTIATE_SCOPED_PRIMITIVE_ARRAY_RW(jfloat, Float);
INSTANTIATE_SCOPED_PRIMITIVE_ARRAY_RW(jint, Int);
INSTANTIATE_SCOPED_PRIMITIVE_ARRAY_RW(jlong, Long);
INSTANTIATE_SCOPED_PRIMITIVE_ARRAY_RW(jshort, Short);

#undef INSTANTIATE_SCOPED_PRIMITIVE_ARRAY_RW

#endif  // SCOPEDPRIMITIVEARRAY_H_