[#63] Saving in parallel thread (Part 8: Fixed crash when insufficient amount of space on disk)

Author: tomas-nestorovic

Main/src/Dsk5.cpp

@@ -220,6 +220,8 @@ formatError: ::SetLastError(ERROR_BAD_FORMAT);
 		CFile f;
 		if (const TStdWinError err=CreateImageForWriting(lpszPathName,f))
 			return err;
+		if (GetCurrentDiskFreeSpace()<sizeof(TDiskInfo))
+			return ERROR_DISK_FULL;
 		f.Write(&diskInfo,sizeof(TDiskInfo));
 		const PTrackInfo *ppti=tracks;
 		if (params.rev5){
@@ -228,8 +230,11 @@ formatError: ::SetLastError(ERROR_BAD_FORMAT);
 			for( BYTE track=0,*pOffset256=diskInfo.rev5_trackOffsets256; track<DSK_REV5_TRACKS_MAX; pOffset256++,ppti++,ap.UpdateProgress(++track) )
 				if (ap.Cancelled)
 					return ERROR_CANCELLED;
-				else if (const BYTE tmp=*pOffset256)
-					f.Write(*ppti,tmp<<8);
+				else if (const DWORD tmp=*pOffset256<<8)
+					if (GetCurrentDiskFreeSpace()<tmp)
+						return ERROR_DISK_FULL;
+					else
+						f.Write(*ppti,tmp);
 		}else{
 			// standard DSK
 			bool mayLeadToIncompatibilityIssues=false; // assumption (none Track contains assets that could potentially lead to unreadability in randomly selected emulator)
@@ -238,6 +243,8 @@ formatError: ::SetLastError(ERROR_BAD_FORMAT);
 				for( THead head=diskInfo.nHeads; head--; ){
 					const TTrackInfo *const ti=*ppti++;
 					WORD trackLength=sizeof(TTrackInfo)+__getTrackLength256__(ti);
+					if (GetCurrentDiskFreeSpace()<diskInfo.std_trackLength)
+						return ERROR_DISK_FULL;
 					f.Write( ti, trackLength );
 					if (trackLength<diskInfo.std_trackLength){
 						for( static constexpr BYTE Zero=0; trackLength++<diskInfo.std_trackLength; f.Write(&Zero,1) );

Main/src/Image.cpp

@@ -334,6 +334,15 @@ namespace Medium{
 		return (PImage)CMainWindow::CTdiTemplate::pSingleInstance->__getDocument__();
 	}
 
+	DWORD CImage::GetCurrentDiskFreeSpace(){
+		// determines and returns number of free Bytes on current working disk (nullptr below); this function to be used during Image saving to avoid exceptions (for can't use try-catch blocks in "MFC4.2" release!)
+		DWORD nSectorsPerCluster,nBytesPerSector,nFreeClusters,nAllClusters;
+		if (!::GetDiskFreeSpace( nullptr, &nSectorsPerCluster, &nBytesPerSector, &nFreeClusters, &nAllClusters ))
+			return 0;
+		const auto nFreeBytes=(ULONGLONG)nSectorsPerCluster*nBytesPerSector*nFreeClusters;
+		return	nFreeBytes<ULONG_MAX ? nFreeBytes : ULONG_MAX;
+	}
+
 	TStdWinError CImage::OpenImageForReading(LPCTSTR fileName,CFile &f){
 		// True <=> File successfully opened for reading, otherwise False
 		CFileException e;

Main/src/Image.h

@@ -251,6 +251,7 @@
 		void Patch();
 		void OnCloseDocument() override sealed;
 	protected:
+		static DWORD GetCurrentDiskFreeSpace();
 		static TStdWinError OpenImageForReading(LPCTSTR fileName,CFile &f);
 		static TStdWinError OpenImageForReadingAndWriting(LPCTSTR fileName,CFile &f);
 		static TStdWinError CreateImageForWriting(LPCTSTR fileName,CFile &f);

Main/src/ImageRaw.cpp

@@ -106,9 +106,11 @@
 		return TRUE;
 	}
 
-	void CImageRaw::__saveTrackToCurrentPositionInFile__(CFile *pfOtherThanCurrentFile,TPhysicalAddress chs){
-		// saves Track defined by the {Cylinder,Head} pair in PhysicalAddress to the current position in the open file; after saving, the position in the file will advance immediately "after" the just saved Track
+	TStdWinError CImageRaw::SaveTrackToCurrentPositionInFile(CFile *pfOtherThanCurrentFile,TPhysicalAddress chs){
+		// saves Track defined by the {Cylinder,Head} pair in PhysicalAddress to the current position in the open file, returning Windows standard i/o error; after saving, the position in the file will advance immediately "after" the just saved Track
 		for( TSector s=0; s<nSectors; s++ ){
+			if (GetCurrentDiskFreeSpace()<sectorLength)
+				return ERROR_DISK_FULL;
 			chs.sectorId.sector=firstSectorNumber+s;
 			const PCSectorData bufferedData=__getBufferedSectorData__(chs.cylinder,chs.head,&chs.sectorId);
 			if (!pfOtherThanCurrentFile){
@@ -128,6 +130,7 @@
 					pfOtherThanCurrentFile->Write( buffer, f.Read(buffer,sectorLength) );
 				}
 		}
+		return ERROR_SUCCESS;
 	}
 
 	TStdWinError CImageRaw::SaveAllModifiedTracks(LPCTSTR lpszPathName,CActionProgress &ap){
@@ -148,14 +151,16 @@
 				for( chs.cylinder=0; chs.cylinder<nCylinders; chs.cylinder++ )
 					for( chs.sectorId.cylinder=chs.cylinder,chs.head=0; chs.head<nHeads; chs.head++,ap.IncrementProgress() ){
 						chs.sectorId.side=sideMap[chs.head];
-						__saveTrackToCurrentPositionInFile__( savingToCurrentFile?nullptr:&fTmp, chs );
+						if (const TStdWinError err=SaveTrackToCurrentPositionInFile( savingToCurrentFile?nullptr:&fTmp, chs ))
+							return err;
 					}
 				break;
 			case TTrackScheme::BY_SIDES:
 				for( chs.head=0; chs.head<nHeads; chs.head++ )
 					for( chs.sectorId.side=sideMap[chs.head],chs.cylinder=0; chs.cylinder<nCylinders; chs.cylinder++,ap.IncrementProgress() ){
 						chs.sectorId.cylinder=chs.cylinder;
-						__saveTrackToCurrentPositionInFile__( savingToCurrentFile?nullptr:&fTmp, chs );
+						if (const TStdWinError err=SaveTrackToCurrentPositionInFile( savingToCurrentFile?nullptr:&fTmp, chs ))
+							return err;
 					}
 				break;
 			default:

Main/src/ImageRaw.h

@@ -10,7 +10,7 @@
 
 		bool IsKnownSector(TCylinder cyl,THead head,RCSectorId id) const;
 		PSectorData __getBufferedSectorData__(TCylinder cyl,THead head,PCSectorId sectorId) const;
-		void __saveTrackToCurrentPositionInFile__(CFile *pfOtherThanCurrentFile,TPhysicalAddress chs);
+		TStdWinError SaveTrackToCurrentPositionInFile(CFile *pfOtherThanCurrentFile,TPhysicalAddress chs);
 	protected:
 		TTrackScheme trackAccessScheme;
 		Utils::CCallocPtr<TSide,THead> explicitSides; // non-Null = Side numbers explicitly provided by user

Main/src/KryoFluxStreams.cpp

@@ -133,7 +133,10 @@
 				if (!f.Open( GetStreamFileName(cyl,head), CFile::modeCreate|CFile::modeWrite|CFile::typeBinary|CFile::shareExclusive, &e ))
 					return e.m_cause;
 				if (const auto data=Utils::MakeCallocPtr<BYTE>(KF_BUFFER_CAPACITY)){
-					f.Write( data, TrackToStream(*pit,data) );
+					const DWORD nTrackBytes=TrackToStream(*pit,data);
+					if (GetCurrentDiskFreeSpace()<nTrackBytes)
+						return ERROR_DISK_FULL;
+					f.Write( data, nTrackBytes );
 					pit->modified=false;
 				}else
 					return ERROR_NOT_ENOUGH_MEMORY;

Main/src/SCL.cpp

@@ -66,18 +66,24 @@
 			TSclHeader header;
 			::lstrcpyA( header.id, HEADER_SINCLAIR );
 			header.nFiles=boot->nFiles;
+			if (GetCurrentDiskFreeSpace()<sizeof(header))
+				return ERROR_DISK_FULL;
 			f.Write(&header,sizeof(header));
 			// - saving Directory
 			CTRDOS503 *const trdos=(CTRDOS503 *)dos;
 			CTRDOS503::PDirectoryEntry directory[TRDOS503_FILE_COUNT_MAX],*pde=directory;
+			if (GetCurrentDiskFreeSpace()<n*sizeof(TSclDirectoryItem))
+				return ERROR_DISK_FULL;
 			for( BYTE n=trdos->__getDirectory__(directory); n--; f.Write(*pde++,sizeof(TSclDirectoryItem)) );
 			// - saving each File's data
 	{		const Utils::CVarTempReset<CDos::TGetFileSizeOptions> gfso0( trdos->getFileSizeDefaultOption, CDos::TGetFileSizeOptions::SizeOnDisk ); // exporting whole Sectors instead of just reported File length
 				BYTE buf[65536];
-				for( pde=directory; header.nFiles--; )
-					f.Write(buf,
-							trdos->ExportFile( *pde++, &CMemFile(buf,sizeof(buf)), sizeof(buf), nullptr )
-						);
+				for( pde=directory; header.nFiles--; ){
+					const DWORD fileLength=trdos->ExportFile( *pde++, &CMemFile(buf,sizeof(buf)), sizeof(buf), nullptr );
+					if (GetCurrentDiskFreeSpace()<fileLength)
+						return ERROR_DISK_FULL;
+					f.Write( buf, fileLength );
+				}
 				m_bModified=FALSE;
 	}		// - reopening the Image's underlying file
 			f.Close();

Main/src/SCP.cpp

@@ -202,10 +202,12 @@ formatError: ::SetLastError(ERROR_BAD_FORMAT);
 								pit->FlushSectorBuffers(); // convert all modifications into flux transitions
 								if (const DWORD trackLength=TrackToStream( *pit, CMemFile(buffer,SCP_BUFFER_CAPACITY), cylFile, head, bStreamAdjusted )){
 									// conversion of the Track to SuperCardPro stream succeeded?
+									const LONG capacity=((TTrackDataHeader *)buffer.get())->GetFullTrackCapacityInBytes( mp, header );
+									if (GetCurrentDiskFreeSpace()<capacity)
+										return ERROR_DISK_FULL;
 									// . success thanks to adjustments to overcome SuperCard Pro limitations?
 									header.flags.normalized|=bStreamAdjusted;
 									// . search for sufficiently big gap
-									const LONG capacity=((TTrackDataHeader *)buffer.get())->GetFullTrackCapacityInBytes( mp, header );
 									tdhOffsets[cylFile][head]=fTargetLength; // assumption (no gap big enough to contain this Track, so must extend the file)
 									for( auto it=contentLayout.begin(); it!=contentLayout.end(); it++ )
 										if (it->second<0 && it->second<=-capacity){ // a gap that can contain the Track
@@ -233,11 +235,14 @@ formatError: ::SetLastError(ERROR_BAD_FORMAT);
 							pit->FlushSectorBuffers(); // convert all modifications into flux transitions
 							if (const DWORD trackLength=TrackToStream( *pit, CMemFile(buffer,SCP_BUFFER_CAPACITY), cylFile, head, bStreamAdjusted )){
 								// conversion of the Track to SuperCardPro stream succeeded?
+								const LONG capacity=((TTrackDataHeader *)buffer.get())->GetFullTrackCapacityInBytes( mp, header );
+								if (GetCurrentDiskFreeSpace()<capacity)
+									return ERROR_DISK_FULL;
 								// . success thanks to adjustments to overcome SuperCard Pro limitations?
 								header.flags.normalized|=bStreamAdjusted;
 								// . append Track to file
 								fTarget.SetLength( // make reserve so that the Track can expand upon different data
-									fTargetLength + ((TTrackDataHeader *)buffer.get())->GetFullTrackCapacityInBytes( mp, header )
+									fTargetLength + capacity
 								);
 								fTarget.Seek(
 									tdhOffsets[cylFile][head] = fTargetLength,
@@ -252,8 +257,11 @@ formatError: ::SetLastError(ERROR_BAD_FORMAT);
 							if (!tdh.Read( f, cylFile, head, header.nAvailableRevolutions ))
 								return ERROR_INVALID_BLOCK; // read invalid TrackDataHeader structure
 							f.Seek( tdhOffset, CFile::begin ); // seek back to the TrackDataHeader
+							const DWORD capacity=tdh.GetFullTrackCapacityInBytes( mp, header );
+							if (GetCurrentDiskFreeSpace()<capacity)
+								return ERROR_DISK_FULL;
 							fTarget.SetLength( // make reserve so that the Track can expand upon different data
-								fTargetLength + tdh.GetFullTrackCapacityInBytes( mp, header )
+								fTargetLength + capacity
 							);
 							fTarget.Seek( // append Track to file
 								tdhOffsets[cylFile][head] = fTargetLength,
@@ -277,6 +285,8 @@ formatError: ::SetLastError(ERROR_BAD_FORMAT);
 		}*/
 		// - save Offsets
 		fTarget.Seek( sizeof(header)+header.flags.extended*0x70, CFile::begin );
+		if (GetCurrentDiskFreeSpace()<sizeof(tdhOffsets))
+			return ERROR_DISK_FULL;
 		fTarget.Write( tdhOffsets, sizeof(tdhOffsets) );
 		// - update Header
 		header.signatureAndRevision=THeader().signatureAndRevision;
@@ -322,7 +332,7 @@ formatError: ::SetLastError(ERROR_BAD_FORMAT);
 			}while (fTarget.GetPosition()<fTarget.GetLength());
 		}
 		fTarget.SeekToBegin();
-		fTarget.Write( &header, sizeof(header) );
+		fTarget.Write( &header, sizeof(header) ); // no need to test free space on disk - we would already fail somewhere above
 		m_bModified=FALSE;
 		// - reopening Image's underlying file
 		if (f.m_hFile!=CFile::hFileNull)