/*
  zip_file_rename.c -- rename file in zip archive
  Copyright (C) 1999-2019 Dieter Baron and Thomas Klausner

  This file is part of libzip, a library to manipulate ZIP archives.
  The authors can be contacted at <libzip@nih.at>

  Redistribution and use in source and binary forms, with or without
  modification, are permitted provided that the following conditions
  are met:
  1. Redistributions of source code must retain the above copyright
     notice, this list of conditions and the following disclaimer.
  2. Redistributions in binary form must reproduce the above copyright
     notice, this list of conditions and the following disclaimer in
     the documentation and/or other materials provided with the
     distribution.
  3. The names of the authors may not be used to endorse or promote
     products derived from this software without specific prior
     written permission.

  THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS
  OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY
  DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
  GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
  IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
  OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
  IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/


#include <string.h>

#include "zipint.h"


ZIP_EXTERN int
zip_file_rename(zip_t *za, zip_uint64_t idx, const char *name, zip_flags_t flags) {
    const char *old_name;
    int old_is_dir, new_is_dir;

    if (idx >= za->nentry || (name != NULL && strlen(name) > ZIP_UINT16_MAX)) {
	zip_error_set(&za->error, ZIP_E
/*
 Derived from source code of TrueCrypt 7.1a, which is
 Copyright (c) 2008-2012 TrueCrypt Developers Association and which is governed
 by the TrueCrypt License 3.0.

 Modifications and additions to the original source code (contained in this file)
 and all other portions of this file are Copyright (c) 2013-2016 IDRIX
 and are governed by the Apache License 2.0 the full text of which is
 contained in the file License.txt included in VeraCrypt binary and source
 code distribution packages.
*/

#ifdef TC_UNIX
#	include <unistd.h>
#endif

#ifdef TC_MACOSX
#	include <sys/types.h>
#	include <sys/sysctl.h>
#endif

#include "Platform/SyncEvent.h"
#include "Platform/SystemLog.h"
#include "Common/Crypto.h"
#include "EncryptionThreadPool.h"

namespace VeraCrypt
{
	void EncryptionThreadPool::DoWork (WorkType::Enum type, const EncryptionMode *encryptionMode, byte *data, uint64 startUnitNo, uint64 unitCount, size_t sectorSize)
	{
		size_t fragmentCount;
		size_t unitsPerFragment;
		size_t remainder;

		byte *fragmentData;
		uint64 fragmentStartUnitNo;

		WorkItem *workItem;
		WorkItem *firstFragmentWorkItem;

		if (unitCount == 0)
			return;

		if (!ThreadPoolRunning || unitCount == 1)
		{
			switch (type)
			{
			case WorkType::DecryptDataUnits:
				encryptionMode->DecryptSectorsCurrentThread (data, startUnitNo, unitCount, sectorSize);
				break;

			case WorkType::EncryptDataUnits:
				encryptionMode->EncryptSectorsCurrentThread (data, startUnitNo, unitCount, sectorSize);
				break;

			default:
				throw ParameterIncorrect (SRC_POS);
			}

			return;
		}

		if (unitCount <= ThreadCount)
		{
			fragmentCount = (size_t) unitCount;
			unitsPerFragment = 1;
			remainder = 0;
		}
		else
		{
			fragmentCount = ThreadCount;
			unitsPerFragment = (size_t) unitCount / ThreadCount;
			remainder = (size_t) unitCount % ThreadCount;

			if (remainder > 0)
				++unitsPerFragment;
		}

		fragmentData = data;
		fragmentStartUnitNo = startUnitNo;

		{
			ScopeLock lock (EnqueueMutex);
			firstFragmentWorkItem = &WorkItemQueue[EnqueuePosition];

			while (firstFragmentWorkItem->State != WorkItem::State::Free)
			{
				WorkItemCompletedEvent.Wait();
			}

			firstFragmentWorkItem->OutstandingFragmentCount.Set (fragmentCount);
			firstFragmentWorkItem->ItemException.reset();

			while (fragmentCount-- > 0)
			{
				workItem = &WorkItemQueue[EnqueuePosition++];

				if (EnqueuePosition >= QueueSize)
					EnqueuePosition = 0;

				while (workItem->State != WorkItem::State::Free)
				{
					WorkItemCompletedEvent.Wait();
				}

				workItem->Type = type;
				workItem->FirstFragment = firstFragmentWorkItem;

				workItem->Encryption.Mode = encryptionMode;
				workItem->Encryption.Data = fragmentData;
				workItem->Encryption.UnitCount = unitsPerFragment;
				workItem->Encryption.StartUnitNo = fragmentStartUnitNo;
				workItem->Encryption.SectorSize = sectorSize;

				fragmentData += unitsPerFragment * sectorSize;
				fragmentStartUnitNo += unitsPerFragment;

				if (remainder > 0 && --remainder == 0)
					--unitsPerFragment;

				workItem->State.Set (WorkItem::State::Ready);
				WorkItemReadyEvent.Signal();
			}
		}

		firstFragmentWorkItem->ItemCompletedEvent.Wait();

		auto_ptr <Exception> itemException;
		if (firstFragmentWorkItem->ItemException.get())
			itemException = firstFragmentWorkItem->ItemException;

		firstFragmentWorkItem->State.Set (WorkItem::State::Free);
		WorkItemCompletedEvent.Signal();

		if (itemException.get())
			itemException->Throw();
	}

	void EncryptionThreadPool::Start ()
	{
		if (ThreadPoolRunning)
			return;

		size_t cpuCount;

#ifdef TC_WINDOWS

		SYSTEM_INFO sysInfo;
		GetSystemInfo (&sysInfo);
		cpuCount = sysInfo.dwNumberOfProcessors;

#elif defined (_SC_NPROCESSORS_ONLN)

		cpuCount = (size_t) sysconf (_SC_NPROCESSORS_ONLN);
		if (cpuCount == (size_t) -1)
			cpuCount = 1;

#elif defined (TC_MACOSX)

		int cpuCountSys;
		int mib[2] = { CTL_HW, HW_NCPU };

		size_t len = sizeof (cpuCountSys);
		if (sysctl (mib, 2, &cpuCountSys, &len, nullptr, 0) == -1)
			cpuCountSys = 1;

		cpuCount = (size_t) cpuCountSys;

#else
#	error Cannot determine CPU count
#endif

		if (cpuCount < 2)
			return;

		if (cpuCount > MaxThreadCount)
			cpuCount = MaxThreadCount;

		StopPending = false;
		DequeuePosition = 0;
		EnqueuePosition = 0;

		for (size_t i = 0; i < sizeof (WorkItemQueue) / sizeof (WorkItemQueue[0]); ++i)
		{
			WorkItemQueue[i].State.Set (WorkItem::State::Free);
		}

		try
		{
			for (ThreadCount = 0; ThreadCount < cpuCount; ++ThreadCount)
			{
				struct ThreadFunctor : public Functor
				{
					virtual void operator() ()
					{
						WorkThreadProc();
					}
				};

				make_shared_auto (Thread, thread);
				thread->Start (new ThreadFunctor ());
				RunningThreads.push_back (thread);
			}
		}
		catch (...)
		{
			try
			{
				ThreadPoolRunning = true;
				Stop();
			} catch (...) { }

			throw;
		}

		ThreadPoolRunning = true;
	}

	void EncryptionThreadPool::Stop ()
	{
		if (!ThreadPoolRunning)
			return;

		StopPending = true;
		WorkItemReadyEvent.Signal();

		foreach_ref (const Thread &thread, RunningThreads)
		{
			thread.Join();
		}

		ThreadCount = 0;
		ThreadPoolRunning = false;
	}

	void EncryptionThreadPool::WorkThreadProc ()
	{
		try
		{
			WorkItem *workItem;

			while (!StopPending)
			{
				{
					ScopeLock lock (DequeueMutex);

					workItem = &WorkItemQueue[DequeuePosition++];

					if (DequeuePosition >= QueueSize)
						DequeuePosition = 0;

					while (!StopPending && workItem->State != WorkItem::State::Ready)
					{
						WorkItemReadyEvent.Wait();
					}

					workItem->State.Set (WorkItem::State::Busy);
				}

				if (StopPending)
					break;

				try
				{
					switch (workItem->Type)
					{
					case WorkType::DecryptDataUnits:
						workItem->Encryption.Mode->DecryptSectorsCurrentThread (workItem->Encryption.Data, workItem->Encryption.StartUnitNo, workItem->Encryption.UnitCount, workItem->Encryption.SectorSize);
						break;

					case WorkType::EncryptDataUnits:
						workItem->Encryption.Mode->EncryptSectorsCurrentThread (workItem->Encryption.Data, workItem->Encryption.StartUnitNo, workItem->Encryption.UnitCount, workItem->Encryption.SectorSize);
						break;

					default:
						throw ParameterIncorrect (SRC_POS);
					}
				}
				catch (Exception &e)
				{
					workItem->FirstFragment->ItemException.reset (e.CloneNew());
				}
				catch (exception &e)
				{
					workItem->FirstFragment->ItemException.reset (new ExternalException (SRC_POS, StringConverter::ToExceptionString (e)));
				}
				catch (...)
				{
					workItem->FirstFragment->ItemException.reset (new UnknownException (SRC_POS));
				}

				if (workItem != workItem->FirstFragment)
				{
					workItem->State.Set (WorkItem::State::Free);
					WorkItemCompletedEvent.Signal();
				}

				if (workItem->FirstFragment->OutstandingFragmentCount.Decrement() == 0)
					workItem->FirstFragment->ItemCompletedEvent.Signal();
			}
		}
		catch (exception &e)
		{
			SystemLog::WriteException (e);
		}
		catch (...)
		{
			SystemLog::WriteException (UnknownException (SRC_POS));
		}
	}

	volatile bool EncryptionThreadPool::ThreadPoolRunning = false;
	volatile bool EncryptionThreadPool::StopPending = false;

	size_t EncryptionThreadPool::ThreadCount;

	EncryptionThreadPool::WorkItem EncryptionThreadPool::WorkItemQueue[QueueSize];

	volatile size_t EncryptionThreadPool::EnqueuePosition;
	volatile size_t EncryptionThreadPool::DequeuePosition;

	Mutex EncryptionThreadPool::EnqueueMutex;
	Mutex EncryptionThreadPool::DequeueMutex;

	SyncEvent EncryptionThreadPool::WorkItemReadyEvent;
	SyncEvent EncryptionThreadPool::WorkItemCompletedEvent;

	list < shared_ptr <Thread> > EncryptionThreadPool::RunningThreads;
}