// Copyright 2019-2020 CERN and copyright holders of ALICE O2.

// See https://alice-o2.web.cern.ch/copyright for details of the copyright holders.

// All rights not expressly granted are reserved.

//

// This software is distributed under the terms of the GNU General Public

// License v3 (GPL Version 3), copied verbatim in the file "COPYING".

//

// In applying this license CERN does not waive the privileges and immunities

// granted to it by virtue of its status as an Intergovernmental Organization

// or submit itself to any jurisdiction.

#include <Common/Fifo.h>

#include <memory>

#include <mutex>

#include <stdint.h>

#include <string>

#include "DataBlockContainer.h"

#include "ReadoutUtils.h"

struct MemoryRegion {

unsigned long long size; // size of memory block

void* ptr; // pointer to memory block

std::string name; // name of the region

// todo: add callback to release region afterwards

unsigned long long usedSize; // amount of memory in use

};

extern std::unique_ptr<MemoryRegion> bigBlock;

// todo: named list of big blocks, with get/set functions

// todo: big blocks: one different per equipment to avoid lock

// a big block of memory for I/O

class MemoryHandler

{

public:

MemoryHandler(int pageSize, int numberOfPages);

~MemoryHandler();

void* getPage();

void freePage(void*);

void* getBaseAddress();

size_t getSize();

size_t getPageSize();

private:

size_t memorySize; // total size of buffer

size_t pageSize; // size of each superpage in buffer (not the one of getpagesize())

size_t numberOfPages; // number of pages allocated

uint8_t* baseAddress; // base address of buffer

std::unique_ptr<AliceO2::Common::Fifo<long>> pagesAvailable; // a buffer to keep track of individual pages. storing offset (with respect to base address) of pages available

};

class DataBlockContainerFromMemoryHandler : public DataBlockContainer

{

private:

std::shared_ptr<MemoryHandler> mMemoryHandler;

public:

DataBlockContainerFromMemoryHandler(std::shared_ptr<MemoryHandler> const& h) : DataBlockContainer((DataBlock*)nullptr)

{

mMemoryHandler = h;

data = nullptr;

try {

data = new DataBlock;

} catch (...) {

throw __LINE__;

}

data->data = (char*)h->getPage();

if (data->data == nullptr) {

delete data;

throw __LINE__;

}

// printf("In use: page %p\n",data->data);

}

~DataBlockContainerFromMemoryHandler()

{

if (data != nullptr) {

// printf("~DataBlockContainerFromMemoryHandler(%p) : header=%p data=%p\n",this,data,data->data);

if (data->data != nullptr) {

mMemoryHandler->freePage(data->data);

}

delete data;

}

}

};