/*

* Copyright (c) 2009 Nokia Corporation and/or its subsidiary(-ies).

* All rights reserved.

*

* This program is free software: you can redistribute it and/or modify

* it under the terms of the GNU Lesser General Public License as published by

* the Free Software Foundation, either version 3 of the License, or

* (at your option) any later version.

*

* This program is distributed in the hope that it will be useful,

* but WITHOUT ANY WARRANTY; without even the implied warranty of

* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

* GNU Lesser General Public License for more details.

* 

* You should have received a copy of the GNU Lesser General Public License

* along with this program.  If not, see <http://www.gnu.org/licenses/>.

*/

#include <sys/types.h>

#include <sys/stat.h>

#include <fcntl.h>

#include <cstdio>

#include <cstdlib>

#include <unistd.h>

#include <cassert>

#include "outputfile.h"

static const size_t NumReservedFileFragments = 100;

OutputFile::OutputFile(PathName aFileName) :

	iFileName(aFileName), iOpened(false), iFd(-1), iCurrentOffset(0)

{

	assert(iFileName.size() != 0);

	// reserve space for file fragments

	iFileFragments.reserve(NumReservedFileFragments);

}

OutputFile::~OutputFile(){

	iFileFragments.clear();

	if (iOpened)

		Close();

}

void OutputFile::Close(){

	if (iOpened) {

		close(iFd);

		iOpened = false;

	}

}

void OutputFile::Flush(){

	if (!iOpened)

		Open();

	if (iFileFragments.size() > 0) {

		FragmentList::iterator aFrag = iFileFragments.begin();

		FragmentList::iterator end = iFileFragments.end();

		while (aFrag != end) {

			aFrag->Write(this);

			aFrag++;

		}

		iFileFragments.clear();

	}	

}

void OutputFile::Dump(){

	Flush();

	Close();

}

const FileFragment & OutputFile::GetFileFragment(FileFragmentOwner * aOwner){

	size_t aSize = aOwner->Size();

	FileFragment aFragment(iCurrentOffset, aSize, aOwner);

	iFileFragments.push_back(aFragment);

	iCurrentOffset += ALIGN4(aSize);

	return  iFileFragments.back();

}

void OutputFile::Open(){

	if (!iOpened) {

		if ((iFd = open(iFileName.c_str(), O_WRONLY | O_CREAT | O_BINARY | O_TRUNC, S_IRUSR | S_IWUSR)) == -1) {

			char msg[1000];

			sprintf(msg, "Output file %s", iFileName.c_str());

			perror(msg);

			exit(EXIT_FAILURE);

		}

		iOpened = true;

	}

}

void OutputFile::Write(size_t aOffset, size_t aSize, char * aData){

	assert(((aSize==0) && (aData==NULL)) || ((aSize>0) && (aData!=NULL)));

	if (aSize == 0) return;

	char msg[1000];

#ifndef USE_PWRITE

	if (lseek(iFd, aOffset, SEEK_SET) != (int)aOffset) {

		sprintf(msg, "Failed to seek to offset %d in output file %s", aOffset, iFileName.c_str());

		goto error;

	}

	for (size_t n = 0; n < aSize;) {

		if ((int)(n += write(iFd, aData+n, aSize - n)) == -1) {

			sprintf(msg, "Failed to write to output file %s", iFileName.c_str());

			goto error;			

		}

	}

#else

	for (size_t n = 0; n < aSize;) {

		if ((n += pwrite(iFd, aData+n, aSize - n, aOffset + n)) == -1) {

			sprintf(msg, "Failed to write to output file %s", iFileName.c_str());

			goto error;			

		}

	}	

#endif

	return;

error:

		perror(msg);

// should we close the file and delete it??		

#ifdef DELETE_OUTPUT_ON_ERROR

		Close();

		unlink(iFileName);

#endif

		exit(EXIT_FAILURE);

}