common/src/shared_block.cpp

/*
 * 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.
 */
#include "shared_block.h"
#include <ashmem.h>
#include <fcntl.h>
#include <securec.h>
#include <sys/mman.h>
#include <unistd.h>

#include <codecvt>
#include <iostream>

#include "string_ex.h"
#include "datashare_log.h"

namespace OHOS {
namespace AppDataFwk {
using namespace OHOS::DataShare;
SharedBlock::SharedBlock(const std::string &name, sptr<Ashmem> ashmem, size_t size, bool readOnly)
    : mName(name), ashmem_(ashmem), mSize(size), mReadOnly(readOnly), mHeader(nullptr)
{
}

SharedBlock::~SharedBlock()
{
    if (ashmem_ != nullptr) {
        ashmem_->UnmapAshmem();
        ashmem_->CloseAshmem();
        LOG_DEBUG("SharedBlock: close ashmem");
    }
}

std::u16string SharedBlock::ToUtf16(const std::string& str)
{
    return OHOS::Str8ToStr16(str);
}

std::string SharedBlock::ToUtf8(const std::u16string& str16)
{
    return OHOS::Str16ToStr8(str16);
}

bool SharedBlock::Init()
{
    mData = const_cast<void *>(ashmem_->ReadFromAshmem(sizeof(SharedBlockHeader), 0));
    mHeader = static_cast<SharedBlockHeader *>(mData);
    if (mHeader == nullptr) {
        return false;
    }
    return true;
}

int SharedBlock::CreateSharedBlock(const std::string &name, size_t size, sptr<Ashmem> ashmem,
    SharedBlock *&outSharedBlock)
{
    outSharedBlock = new SharedBlock(name, ashmem, size, false);
    if (outSharedBlock == nullptr) {
        LOG_ERROR("CreateSharedBlock: new SharedBlock error.");
        return SHARED_BLOCK_BAD_VALUE;
    }

    if (!outSharedBlock->Init()) {
        delete outSharedBlock;
        outSharedBlock = nullptr;
        LOG_ERROR("CreateSharedBlock: mHeader is null.");
        return SHARED_BLOCK_ASHMEM_ERROR;
    }
    return SHARED_BLOCK_OK;
}

int SharedBlock::Create(const std::string &name, size_t size, SharedBlock *&outSharedBlock)
{
    std::string ashmemName = "SharedBlock:" + name;

    sptr<Ashmem> ashmem = Ashmem::CreateAshmem(ashmemName.c_str(), size);
    if (ashmem == nullptr) {
        LOG_ERROR("SharedBlock: CreateAshmem function error.");
        return SHARED_BLOCK_ASHMEM_ERROR;
    }

    bool ret = ashmem->MapReadAndWriteAshmem();
    if (!ret) {
        LOG_ERROR("SharedBlock: MapReadAndWriteAshmem function error.");
        ashmem->CloseAshmem();
        return SHARED_BLOCK_SET_PORT_ERROR;
    }

    int result = CreateSharedBlock(name, size, ashmem, outSharedBlock);
    if (result == SHARED_BLOCK_OK) {
        return SHARED_BLOCK_OK;
    }
    ashmem->UnmapAshmem();
    ashmem->CloseAshmem();
    outSharedBlock = nullptr;
    return result;
}

int SharedBlock::WriteMessageParcel(MessageParcel &parcel)
{
    return parcel.WriteString16(ToUtf16(mName)) && parcel.WriteAshmem(ashmem_);
}

int SharedBlock::ReadMessageParcel(MessageParcel &parcel, SharedBlock *&block)
{
    std::string name = ToUtf8(parcel.ReadString16());
    sptr<Ashmem> ashmem = parcel.ReadAshmem();
    if (ashmem == nullptr) {
        LOG_ERROR("ReadMessageParcel: No ashmem in the parcel.");
        return SHARED_BLOCK_BAD_VALUE;
    }
    bool ret = ashmem->MapReadAndWriteAshmem();
    if (!ret) {
        LOG_ERROR("ReadMessageParcel: MapReadAndWriteAshmem function error.");
        ashmem->CloseAshmem();
        return SHARED_BLOCK_SET_PORT_ERROR;
    }
    block = new (std::nothrow) SharedBlock(name, ashmem, ashmem->GetAshmemSize(), true);
    if (block == nullptr) {
        LOG_ERROR("ReadMessageParcel new SharedBlock error.");
        return SHARED_BLOCK_BAD_VALUE;
    }
    if (!block->Init()) {
        delete block;
        block = nullptr;
        LOG_ERROR("ReadMessageParcel: mHeader is null.");
        return SHARED_BLOCK_ASHMEM_ERROR;
    }

    LOG_DEBUG("Created SharedBlock from parcel: unusedOffset=%{private}" PRIu32 ", "
              "rowNums=%{private}" PRIu32 ", columnNums=%{private}" PRIu32 ", mSize=%{private}d",
              block->mHeader->unusedOffset, block->mHeader->rowNums, block->mHeader->columnNums,
              static_cast<int>(block->mSize));

    return SHARED_BLOCK_OK;
}

int SharedBlock::Clear()
{
    if (mReadOnly) {
        return SHARED_BLOCK_INVALID_OPERATION;
    }

    mHeader->unusedOffset = sizeof(SharedBlockHeader) + sizeof(RowGroupHeader);
    mHeader->firstRowGroupOffset = sizeof(SharedBlockHeader);
    mHeader->rowNums = 0;
    mHeader->columnNums = 0;
    mHeader->startPos_ = 0;
    mHeader->lastPos_ = 0;
    mHeader->blockPos_ = 0;

    RowGroupHeader *firstGroup = static_cast<RowGroupHeader *>(OffsetToPtr(mHeader->firstRowGroupOffset));
    if (!firstGroup) {
        LOG_ERROR("Failed to get group in clear().");
        return SHARED_BLOCK_BAD_VALUE;
    }
    firstGroup->nextGroupOffset = 0;
    return SHARED_BLOCK_OK;
}

int SharedBlock::SetColumnNum(uint32_t numColumns)
{
    if (mReadOnly) {
        return SHARED_BLOCK_INVALID_OPERATION;
    }

    uint32_t cur = mHeader->columnNums;
    if ((cur > 0 || mHeader->rowNums > 0) && cur != numColumns) {
        LOG_ERROR("Trying to go from %{public}" PRIu32 " columns to %{public}" PRIu32 "", cur, numColumns);
        return SHARED_BLOCK_INVALID_OPERATION;
    }
    if (numColumns > COL_MAX_NUM) {
        LOG_ERROR("Trying to set %{public}" PRIu32 " columns out of size", numColumns);
        return SHARED_BLOCK_INVALID_OPERATION;
    }
    mHeader->columnNums = numColumns;
    return SHARED_BLOCK_OK;
}

int SharedBlock::AllocRow()
{
    if (mReadOnly) {
        return SHARED_BLOCK_INVALID_OPERATION;
    }

    uint32_t *rowOffset = AllocRowOffset();
    if (rowOffset == nullptr) {
        return SHARED_BLOCK_NO_MEMORY;
    }

    /* Allocate the units for the field directory */
    size_t fieldDirSize = mHeader->columnNums * sizeof(CellUnit);

    /* Aligned */
    uint32_t fieldDirOffset = Alloc(fieldDirSize, true);
    if (!fieldDirOffset) {
        mHeader->rowNums--;
        LOG_INFO("Alloc the row failed, so back out the new row accounting from allocRowoffset %{public}" PRIu32 "",
            mHeader->rowNums);
        return SHARED_BLOCK_NO_MEMORY;
    }

    CellUnit *fieldDir = static_cast<CellUnit *>(OffsetToPtr(fieldDirOffset));
    if (fieldDir == nullptr) {
        return SHARED_BLOCK_BAD_VALUE;
    }
    int result = memset_s(fieldDir, fieldDirSize, 0, fieldDirSize);
    if (result != 0) {
        LOG_ERROR("Set memory failed");
        return SHARED_BLOCK_NO_MEMORY;
    }

    *rowOffset = fieldDirOffset;
    return SHARED_BLOCK_OK;
}

int SharedBlock::FreeLastRow()
{
    if (mReadOnly) {
        return SHARED_BLOCK_INVALID_OPERATION;
    }

    if (mHeader->rowNums > 0) {
        mHeader->rowNums--;
    }

    return SHARED_BLOCK_OK;
}

uint32_t SharedBlock::Alloc(size_t size, bool aligned)
{
    /* Number of unused offsets in the header */
    uint32_t offsetDigit = 3;
    uint32_t padding = aligned ? (~mHeader->unusedOffset + 1) & offsetDigit : 0;
    uint32_t offset = mHeader->unusedOffset + padding;
    uint32_t nextFreeOffset;

    if (offset + size > mSize) {
        LOG_ERROR("SharedBlock is full: requested allocation %{public}zu bytes,"
            " free space %{public}zu bytes, block size %{public}zu bytes",
            size, mSize - mHeader->unusedOffset, mSize);
        return 0;
    }
    nextFreeOffset = offset + size;
    mHeader->unusedOffset = nextFreeOffset;
    return offset;
}

inline uint32_t *SharedBlock::GetRowOffset(uint32_t row)
{
    uint32_t rowPos = row;

    RowGroupHeader *group = static_cast<RowGroupHeader *>(OffsetToPtr(mHeader->firstRowGroupOffset));
    if (group == nullptr) {
        LOG_ERROR("Failed to get group in getRowOffset().");
        return nullptr;
    }

    while (rowPos >= ROW_OFFSETS_NUM) {
        group = static_cast<RowGroupHeader *>(OffsetToPtr(group->nextGroupOffset));
        if (group == nullptr) {
            LOG_ERROR("Failed to get group in OffsetToPtr(group->nextGroupOffset) when while loop.");
            return nullptr;
        }
        rowPos -= ROW_OFFSETS_NUM;
    }

    return &group->rowOffsets[rowPos];
}

uint32_t *SharedBlock::AllocRowOffset()
{
    uint32_t rowPos = mHeader->rowNums;

    RowGroupHeader *group = static_cast<RowGroupHeader *>(OffsetToPtr(mHeader->firstRowGroupOffset));
    if (group == nullptr) {
        LOG_ERROR("Failed to get group in allocRowOffset().");
        return nullptr;
    }

    while (rowPos > ROW_OFFSETS_NUM) {
        group = static_cast<RowGroupHeader *>(OffsetToPtr(group->nextGroupOffset));
        if (group == nullptr) {
            LOG_ERROR("Failed to get group in OffsetToPtr(group->nextGroupOffset) when while loop.");
            return nullptr;
        }
        rowPos -= ROW_OFFSETS_NUM;
    }
    if (rowPos == ROW_OFFSETS_NUM) {
        if (!group->nextGroupOffset) {
            /* Aligned */
            group->nextGroupOffset = Alloc(sizeof(RowGroupHeader), true);
            if (!group->nextGroupOffset) {
                return nullptr;
            }
        }
        group = static_cast<RowGroupHeader *>(OffsetToPtr(group->nextGroupOffset));
        if (group == nullptr) {
            LOG_ERROR("Failed to get group in OffsetToPtr(group->nextGroupOffset).");
            return nullptr;
        }
        group->nextGroupOffset = 0;
        rowPos = 0;
    }

    mHeader->rowNums += 1;
    return &group->rowOffsets[rowPos];
}

SharedBlock::CellUnit *SharedBlock::GetCellUnit(uint32_t row, uint32_t column)
{
    if (row >= mHeader->rowNums || column >= mHeader->columnNums) {
        LOG_ERROR("Failed to read row %{public}" PRIu32 ", column %{public}" PRIu32 " from a SharedBlock"
            " which has %{public}" PRIu32 " rows, %{public}" PRIu32 " columns.",
            row, column, mHeader->rowNums, mHeader->columnNums);
        return nullptr;
    }

    uint32_t *rowOffset = GetRowOffset(row);
    if (!rowOffset) {
        LOG_ERROR("Failed to find rowOffset for row %{public}" PRIu32 ".", row);
        return nullptr;
    }

    CellUnit *cellUnit = static_cast<CellUnit *>(OffsetToPtr(*rowOffset));
    if (!cellUnit) {
        LOG_ERROR("Failed to find cellUnit for rowOffset %{public}" PRIu32 ".", *rowOffset);
        return nullptr;
    }

    return &cellUnit[column];
}

int SharedBlock::PutBlob(uint32_t row, uint32_t column, const void *value, size_t size)
{
    return PutBlobOrString(row, column, value, size, CELL_UNIT_TYPE_BLOB);
}

int SharedBlock::PutString(uint32_t row, uint32_t column, const char *value, size_t sizeIncludingNull)
{
    return PutBlobOrString(row, column, value, sizeIncludingNull, CELL_UNIT_TYPE_STRING);
}

int SharedBlock::PutBlobOrString(uint32_t row, uint32_t column, const void *value, size_t size, int32_t type)
{
    if (mReadOnly) {
        return SHARED_BLOCK_INVALID_OPERATION;
    }

    CellUnit *cellUnit = GetCellUnit(row, column);
    if (!cellUnit) {
        return SHARED_BLOCK_BAD_VALUE;
    }

    uint32_t offset = Alloc(size);
    if (!offset) {
        return SHARED_BLOCK_NO_MEMORY;
    }

    void *ptr = OffsetToPtr(offset);
    if (!ptr) {
        return SHARED_BLOCK_NO_MEMORY;
    }

    if (size != 0) {
        errno_t result = memcpy_s(ptr, size, value, size);
        if (result != EOK) {
            return SHARED_BLOCK_NO_MEMORY;
        }
    }

    cellUnit->type = type;
    cellUnit->cell.stringOrBlobValue.offset = offset;
    cellUnit->cell.stringOrBlobValue.size = size;
    return SHARED_BLOCK_OK;
}

int SharedBlock::PutLong(uint32_t row, uint32_t column, int64_t value)
{
    if (mReadOnly) {
        return SHARED_BLOCK_INVALID_OPERATION;
    }

    CellUnit *cellUnit = GetCellUnit(row, column);
    if (!cellUnit) {
        return SHARED_BLOCK_BAD_VALUE;
    }

    cellUnit->type = CELL_UNIT_TYPE_INTEGER;
    cellUnit->cell.longValue = value;
    return SHARED_BLOCK_OK;
}

int SharedBlock::PutDouble(uint32_t row, uint32_t column, double value)
{
    if (mReadOnly) {
        return SHARED_BLOCK_INVALID_OPERATION;
    }

    CellUnit *cellUnit = GetCellUnit(row, column);
    if (!cellUnit) {
        return SHARED_BLOCK_BAD_VALUE;
    }

    cellUnit->type = CELL_UNIT_TYPE_FLOAT;
    cellUnit->cell.doubleValue = value;
    return SHARED_BLOCK_OK;
}

int SharedBlock::PutNull(uint32_t row, uint32_t column)
{
    if (mReadOnly) {
        return SHARED_BLOCK_INVALID_OPERATION;
    }

    CellUnit *cellUnit = GetCellUnit(row, column);
    if (!cellUnit) {
        return SHARED_BLOCK_BAD_VALUE;
    }

    cellUnit->type = CELL_UNIT_TYPE_NULL;
    cellUnit->cell.stringOrBlobValue.offset = 0;
    cellUnit->cell.stringOrBlobValue.size = 0;
    return SHARED_BLOCK_OK;
}

size_t SharedBlock::SetRawData(const void *rawData, size_t size)
{
    if (size <= 0) {
        LOG_ERROR("SharedBlock rawData is less than or equal to 0M");
        return SHARED_BLOCK_INVALID_OPERATION;
    }
    if (size > mSize) {
        LOG_ERROR("SharedBlock size is %{public}zu, current byteArray size is %{public}zu", mSize, size);
        return SHARED_BLOCK_NO_MEMORY;
    }

    int result = memcpy_s(mHeader, mSize, rawData, size);
    if (result != 0) {
        return SHARED_BLOCK_NO_MEMORY;
    }
    return SHARED_BLOCK_OK;
}

uint32_t SharedBlock::OffsetFromPtr(void *ptr)
{
    return static_cast<uint8_t *>(ptr) - static_cast<uint8_t *>(mData);
}
} // namespace AppDataFwk
} // namespace OHOS