icinga2/lib/remote/configobjectslock.cpp

62 lines
1.8 KiB
C++

/* Icinga 2 | (c) 2022 Icinga GmbH | GPLv2+ */
#include "remote/configobjectslock.hpp"
#ifndef _WIN32
#include "base/shared-memory.hpp"
#include <boost/interprocess/sync/lock_options.hpp>
#endif /* _WIN32 */
using namespace icinga;
#ifndef _WIN32
// On *nix one process may write config objects while another is loading the config, so this uses IPC.
static SharedMemory<boost::interprocess::interprocess_sharable_mutex> l_ConfigObjectsMutex;
ConfigObjectsExclusiveLock::ConfigObjectsExclusiveLock()
: m_Lock(l_ConfigObjectsMutex.Get())
{
}
ConfigObjectsSharedLock::ConfigObjectsSharedLock(std::try_to_lock_t)
: m_Lock(l_ConfigObjectsMutex.Get(), boost::interprocess::try_to_lock)
{
}
#endif /* _WIN32 */
std::mutex ObjectNameLock::m_Mutex;
std::condition_variable ObjectNameLock::m_CV;
std::map<Type*, std::set<String>> ObjectNameLock::m_LockedObjectNames;
/**
* Locks the specified object name of the given type and unlocks it upon destruction of the instance of this class.
*
* If it is already locked, the call blocks until the lock is released.
*
* @param Type::Ptr ptype The type of the object you want to lock
* @param String objName The object name you want to lock
*/
ObjectNameLock::ObjectNameLock(const Type::Ptr& ptype, const String& objName): m_ObjectName{objName}, m_Type{ptype}
{
std::unique_lock<std::mutex> lock(m_Mutex);
m_CV.wait(lock, [this]{
auto& locked = m_LockedObjectNames[m_Type.get()];
return locked.find(m_ObjectName) == locked.end();
});
// Add the object name to the locked list to block all other threads that try
// to process a message affecting the same object.
m_LockedObjectNames[ptype.get()].emplace(objName);
}
ObjectNameLock::~ObjectNameLock()
{
{
std::unique_lock<std::mutex> lock(m_Mutex);
m_LockedObjectNames[m_Type.get()].erase(m_ObjectName);
}
m_CV.notify_all();
}