You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
57 lines
2.1 KiB
Plaintext
57 lines
2.1 KiB
Plaintext
/**
|
|
* @file
|
|
* @brief
|
|
*
|
|
* @author Thomas Escher
|
|
*/
|
|
|
|
#ifndef CACHE_DATA_ACCESS_H
|
|
#define CACHE_DATA_ACCESS_H
|
|
|
|
#include "slam6d/data_types.h"
|
|
|
|
#include <boost/interprocess/sync/interprocess_upgradable_mutex.hpp>
|
|
#include <boost/interprocess/sync/sharable_lock.hpp>
|
|
|
|
// hide the boost namespace and shorten others
|
|
namespace
|
|
{
|
|
namespace ip = boost::interprocess;
|
|
}
|
|
|
|
|
|
|
|
/**
|
|
* @brief Access object for data in a CacheObject.
|
|
*
|
|
* This object functions as a reading lock on the data in a CacheObject. While any of these objects exists with a lock on a CacheObject it is guaranteed the CacheManager won't remove it from memory when flushing the cache.
|
|
* It is derived from the DataPointer class, which already represents application-specific access operators for this data, and builds the locking functionality on top of it.
|
|
* A CacheDataAccess is returned by the accessing function in a CacheObject as a temporary and is constructed by these means (&&-ctor). Size and data pointer will be copied and the reading lock will also be obtained. When all CacheDataAccess instances for a given CacheObject are destroyed (fell out of scope) all read locks are gone and the CacheManager is able to remove its contained data from memory.
|
|
*/
|
|
class CacheDataAccess : public DataPointer {
|
|
class Lock : public PrivateImplementation {
|
|
public:
|
|
Lock(ip::interprocess_upgradable_mutex& mutex);
|
|
// on destruction, the lock has to be released, which comes from m_lock destruction
|
|
virtual ~Lock() {}
|
|
private:
|
|
ip::sharable_lock<ip::interprocess_upgradable_mutex> m_lock;
|
|
};
|
|
public:
|
|
// CacheDataAccess& operator=(const CacheDataAccess&) = delete;
|
|
// CacheDataAccess(const CacheDataAccess&) = delete;
|
|
|
|
//! Aquires a lock on the mutex and takes assigned data
|
|
CacheDataAccess(ip::interprocess_upgradable_mutex& mutex, unsigned int& size, unsigned char* data);
|
|
|
|
CacheDataAccess(CacheDataAccess&& other) : DataPointer(other) {}
|
|
|
|
//! Non-locking version
|
|
//CacheDataAccess(unsigned int& size, unsigned char* data);
|
|
|
|
//! Transfers the lock to this instance and also takes assigned data
|
|
//CacheDataAccess(const CacheDataAccess& other);
|
|
};
|
|
|
|
#endif //CACHE_DATA_ACCESS_H
|