src/host/async_task.cpp

/*
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 *     notice, this list of conditions and the following disclaimer in the
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 *  3. Neither the name of the copyright holder nor the
 *     names of its contributors may be used to endorse or promote products
 *     derived from this software without specific prior written permission.
 *
 *  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 *  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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 */

#include "async_task.hpp"

#include <assert.h>
#include <memory>

#include "common/code_utils.hpp"

namespace otbr {
namespace Host {

AsyncTask::AsyncTask(const ResultHandler &aResultHandler)
    : mResultHandler(aResultHandler)
{
}

AsyncTask::~AsyncTask()
{
    if (!mNext)
    {
        if (mResultHandler)
        {
            mResultHandler(OT_ERROR_FAILED, "AsyncTask ends without setting any result.");
        }
    }
}

void AsyncTask::Run(void)
{
    SetResult(OT_ERROR_NONE, "");
}

void AsyncTask::SetResult(otError aError, const std::string &aErrorInfo)
{
    if (mNext)
    {
        if (aError == OT_ERROR_NONE)
        {
            mThen(std::move(mNext));
        }
        else
        {
            mNext->SetResult(aError, aErrorInfo);
        }
        mThen = nullptr;
    }
    else
    {
        mResultHandler(aError, aErrorInfo);
        mResultHandler = nullptr;
    }
}

AsyncTaskPtr &AsyncTask::First(const ThenHandler &aFirst)
{
    assert(mNext == nullptr);

    return Then(aFirst);
}

AsyncTaskPtr &AsyncTask::Then(const ThenHandler &aThen)
{
    assert(mNext == nullptr);

    mNext = std::make_shared<AsyncTask>(mResultHandler);
    mThen = aThen;

    return mNext;
}

} // namespace Host
} // namespace otbr