utils_native/base/include/parcel.h

/*
 * Copyright (c) 2021 Huawei Device Co., Ltd.
 * 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 OHOS_UTILS_PARCEL_H
#define OHOS_UTILS_PARCEL_H

#include <string>
#include <vector>
#include "nocopyable.h"
#include "refbase.h"
#include "flat_obj.h"

namespace OHOS {

class Parcel;

class Parcelable : public virtual RefBase {
public:
    virtual ~Parcelable() = default;

    Parcelable();
    explicit Parcelable(bool asRemote);

    // Write a parcelable object to the given parcel.
    // The object position is saved into Parcel if set asRemote_ to
    // true, and this intends to use in kernel data transaction.
    // Returns true being written on success or false if any error occur.
    virtual bool Marshalling(Parcel &parcel) const = 0;

    // NOTICE! A static Unmarshalling function must also be implemented, so
    // that you can get data from the given parcel into this parcelable object.
    // See "static TestParcelable *Unmarshalling(Parcel &parcel)" as an example.

    enum BehaviorFlag { IPC = 0x01, RPC = 0x02, HOLD_OBJECT = 0x10 };

    inline void SetBehavior(BehaviorFlag b) const
    {
        behavior_ |= static_cast<uint8_t>(b);
    }

    inline void ClearBehavior(BehaviorFlag b) const
    {
        behavior_ &= ~(static_cast<uint8_t>(b));
    }

    inline bool TestBehavior(BehaviorFlag b) const
    {
        return behavior_ & (static_cast<uint8_t>(b));
    }

public:
    bool asRemote_;
    mutable uint8_t behavior_;
};

class Allocator {
public:
    virtual ~Allocator() = default;

    virtual void *Realloc(void *data, size_t newSize) = 0;

    virtual void *Alloc(size_t size) = 0;

    virtual void Dealloc(void *data) = 0;
};

class DefaultAllocator : public Allocator {
public:
    virtual void *Alloc(size_t size) override;

    virtual void Dealloc(void *data) override;
private:
    virtual void *Realloc(void *data, size_t newSize) override;
};

class Parcel {
public:
    Parcel();
    explicit Parcel(Allocator *allocator);

    virtual ~Parcel();

    size_t GetDataSize() const;

    uintptr_t GetData() const;

    binder_size_t GetObjectOffsets() const;

    size_t GetOffsetsSize() const;

    size_t GetWritableBytes() const;

    size_t GetReadableBytes() const;

    size_t GetDataCapacity() const;

    bool SetDataCapacity(size_t newCapacity);

    bool SetDataSize(size_t dataSize);

    bool SetMaxCapacity(size_t maxCapacity);

    bool WriteBool(bool value);

    bool WriteInt8(int8_t value);

    bool WriteInt16(int16_t value);

    bool WriteInt32(int32_t value);

    bool WriteInt64(int64_t value);

    bool WriteUint8(uint8_t value);

    bool WriteUint16(uint16_t value);

    bool WriteUint32(uint32_t value);

    bool WriteUint64(uint64_t value);

    bool WriteFloat(float value);

    bool WriteDouble(double value);

    bool WritePointer(uintptr_t value);

    bool WriteBuffer(const void *data, size_t size);

    bool WriteBufferAddTerminator(const void *data, size_t size, size_t typeSize);

    bool WriteUnpadBuffer(const void *data, size_t size);

    bool WriteCString(const char *value);

    bool WriteString(const std::string &value);

    bool WriteString16(const std::u16string &value);

    bool WriteString16WithLength(const char16_t *value, size_t len);

    bool WriteString8WithLength(const char *value, size_t len);

    bool WriteParcelable(const Parcelable *object);

    bool WriteStrongParcelable(const sptr<Parcelable> &object);

    bool WriteRemoteObject(const Parcelable *object);

    template<typename T>
    bool WriteObject(const sptr<T> &object);

    bool ParseFrom(uintptr_t data, size_t size);

    bool ReadBool();

    int8_t ReadInt8();

    int16_t ReadInt16();

    int32_t ReadInt32();

    int64_t ReadInt64();

    uint8_t ReadUint8();

    uint16_t ReadUint16();

    uint32_t ReadUint32();

    uint64_t ReadUint64();

    float ReadFloat();

    double ReadDouble();

    uintptr_t ReadPointer();

    bool ReadBool(bool &value);

    bool ReadInt8(int8_t &value);

    bool ReadInt16(int16_t &value);

    bool ReadInt32(int32_t &value);

    bool ReadInt64(int64_t &value);

    bool ReadUint8(uint8_t &value);

    bool ReadUint16(uint16_t &value);

    bool ReadUint32(uint32_t &value);

    bool ReadUint64(uint64_t &value);

    bool ReadFloat(float &value);

    bool ReadDouble(double &value);

    const uint8_t *ReadBuffer(size_t length);

    const uint8_t *ReadUnpadBuffer(size_t length);

    void SkipBytes(size_t bytes);

    const char *ReadCString();

    const std::string ReadString();

    bool ReadString(std::string &value);

    const std::u16string ReadString16();

    bool ReadString16(std::u16string &value);

    const std::u16string ReadString16WithLength(int32_t &len);

    const std::string ReadString8WithLength(int32_t &len);

    bool RewindRead(size_t newPosition);

    bool RewindWrite(size_t offsets);

    size_t GetReadPosition();

    size_t GetWritePosition();

    template <typename T>
    T *ReadParcelable();

    template <typename T>
    sptr<T> ReadStrongParcelable();

    bool CheckOffsets();

    template<typename T>
    sptr<T> ReadObject();

    bool SetAllocator(Allocator *allocator);

    void InjectOffsets(binder_size_t offsets, size_t offsetSize);

    void FlushBuffer();

    template <typename T1, typename T2>
    bool WriteVector(const std::vector<T1> &val, bool (Parcel::*Write)(T2));
    bool WriteBoolVector(const std::vector<bool> &val);
    bool WriteInt8Vector(const std::vector<int8_t> &val);
    bool WriteInt16Vector(const std::vector<int16_t> &val);
    bool WriteInt32Vector(const std::vector<int32_t> &val);
    bool WriteInt64Vector(const std::vector<int64_t> &val);
    bool WriteUInt8Vector(const std::vector<uint8_t> &val);
    bool WriteUInt16Vector(const std::vector<uint16_t> &val);
    bool WriteUInt32Vector(const std::vector<uint32_t> &val);
    bool WriteUInt64Vector(const std::vector<uint64_t> &val);
    bool WriteFloatVector(const std::vector<float> &val);
    bool WriteDoubleVector(const std::vector<double> &val);
    bool WriteStringVector(const std::vector<std::string> &val);
    bool WriteString16Vector(const std::vector<std::u16string> &val);

    template <typename T>
    bool ReadVector(std::vector<T> *val, bool (Parcel::*Read)(T &));
    bool ReadBoolVector(std::vector<bool> *val);
    bool ReadInt8Vector(std::vector<int8_t> *val);
    bool ReadInt16Vector(std::vector<int16_t> *val);
    bool ReadInt32Vector(std::vector<int32_t> *val);
    bool ReadInt64Vector(std::vector<int64_t> *val);
    bool ReadUInt8Vector(std::vector<uint8_t> *val);
    bool ReadUInt16Vector(std::vector<uint16_t> *val);
    bool ReadUInt32Vector(std::vector<uint32_t> *val);
    bool ReadUInt64Vector(std::vector<uint64_t> *val);
    bool ReadFloatVector(std::vector<float> *val);
    bool ReadDoubleVector(std::vector<double> *val);
    bool ReadStringVector(std::vector<std::string> *val);
    bool ReadString16Vector(std::vector<std::u16string> *val);

    bool WriteBoolUnaligned(bool value);
    bool WriteInt8Unaligned(int8_t value);
    bool WriteInt16Unaligned(int16_t value);
    bool WriteUint8Unaligned(uint8_t value);
    bool WriteUint16Unaligned(uint16_t value);

    bool ReadBoolUnaligned();
    bool ReadInt8Unaligned(int8_t &value);
    bool ReadInt16Unaligned(int16_t &value);
    bool ReadUint8Unaligned(uint8_t &value);
    bool ReadUint16Unaligned(uint16_t &value);

private:
    DISALLOW_COPY_AND_MOVE(Parcel);
    template <typename T>
    bool Write(T value);

    template <typename T>
    bool Read(T &value);

    template <typename T>
    T Read();

    template <typename T>
    bool ReadPadded(T &value);

    inline size_t GetPadSize(size_t size)
    {
        const int SIZE_OFFSET = 3;
        return (((size + SIZE_OFFSET) & (~SIZE_OFFSET)) - size);
    }

    bool WriteObjectOffset(binder_size_t offset);

    size_t CalcNewCapacity(size_t minCapacity);

    bool WriteDataBytes(const void *data, size_t size);

    void WritePadBytes(size_t padded);

    bool EnsureWritableCapacity(size_t desireCapacity);

    bool EnsureObjectsCapacity();

    bool WriteParcelableOffset(size_t offset);

private:
    uint8_t *data_;
    size_t readCursor_;
    size_t writeCursor_;
    size_t dataSize_;
    size_t dataCapacity_;
    size_t maxDataCapacity_;
    binder_size_t *objectOffsets_;
    size_t objectCursor_;
    size_t objectsCapacity_;
    Allocator *allocator_;
    std::vector<sptr<Parcelable>> objectHolder_;
    bool writable_ = true;
};

template <typename T>
bool Parcel::WriteObject(const sptr<T> &object)
{
    if (object == nullptr) {
        return T::Marshalling(*this, object);
    }
    return WriteRemoteObject(object.GetRefPtr());
}

template <typename T>
sptr<T> Parcel::ReadObject()
{
    if (!this->CheckOffsets()) {
        return nullptr;
    }
    return T::Unmarshalling(*this);
}

// Read data from the given parcel into this parcelable object.
template <typename T>
T *Parcel::ReadParcelable()
{
    int32_t size = this->ReadInt32();
    if (size == 0) {
        return nullptr;
    }

    return T::Unmarshalling(*this);
}

// Read data from the given parcel into this parcelable object, return sptr.
template <typename T>
sptr<T> Parcel::ReadStrongParcelable()
{
    int32_t size = this->ReadInt32();
    if (size == 0) {
        return nullptr;
    }

    return T::Unmarshalling(*this);
}

} // namespace OHOS
#endif