private bool GetPieceInfoFromFile(CheckIntegrityCallback callback)
{
string pieceFilePath = Config.ApplicationDataDirectory + IO.Path.DirectorySeparatorChar + this.infofile.PieceFileName + ".piece";
IO.FileInfo pieceFileInfo = new IO.FileInfo(pieceFilePath);
if (pieceFileInfo.Exists)
{
// before we rely on the piece file, do a simple check of file existance and lengths to make sure nothing's changed
for (int i = 0; i < this.infofile.FileCount; ++i)
{
string path = this.infofile.GetFileName(i);
int properLength = this.infofile.GetFileLength(i);
// TODO: introduce modification time check - requires saving time data in piece file
IO.FileInfo fileInfo = new IO.FileInfo(path);
if (!fileInfo.Exists)
{
return(false); // a file doesn't exist, do a proper check
}
long realLength = fileInfo.Length;
if (properLength != realLength)
{
return(false); // a file doesn't have a proper length, do a proper check
}
}
IO.FileStream pieceFile = pieceFileInfo.OpenRead();
int numBytes = this.infofile.PieceCount / 8 + ((this.infofile.PieceCount % 8) > 0 ? 1 : 0);
byte[] data = new byte[numBytes];
pieceFile.Read(data, 0, data.Length);
pieceFile.Close();
this.piecesDownloaded.SetFromRaw(data, 0, data.Length);
this.piecesDownloaded.SetLength(this.infofile.PieceCount);
this.numBytesLeft = 0;
for (int i = 0; i < this.infofile.PieceCount; ++i)
{
if (!this.piecesDownloaded[i])
{
this.numBytesLeft += this.infofile.GetPieceLength(i);
}
}
if (callback != null)
{
callback(this, this.infofile.PieceCount - 1, false, 100.0f);
}
return(true);
}
else
{
return(false);
}
}
/// <summary>
/// This *must* be called before any operations are performed. This should be in the constructor, but as it can be a time-consuming process
/// it was decided against. This analyzes the file to look for which pieces are downloaded, or if the torrent has just started it will create the
/// new, empty files.
/// </summary>
/// <param name="callback">Callback delegate to inform the caller of the progress</param>
public void CheckIntegrity(bool forced, CheckIntegrityCallback callback)
{
// if their already is a piece file in the application directory, load it from there. (unless it is forced where is has to do it)
if (forced || !GetPieceInfoFromFile(callback))
{
int dataPosition = 0, filePosition = 0;
int i = 0;
byte[] data = new byte[this.infofile.GetPieceLength(0)];
Crypto.SHA1 sha = Crypto.SHA1CryptoServiceProvider.Create();
for (int currentFile = 0; currentFile < this.infofile.FileCount; ++currentFile)
{
int fileLength = this.infofile.GetFileLength(currentFile);
string path = this.infofile.GetFileName(currentFile);
IO.FileInfo fileInfo = new IO.FileInfo(path);
if (!fileInfo.Exists)
{
// create the file if it does not exist
this.CreateEmptyFile(fileInfo, fileLength);
int fileDataLeft = 0;
if (dataPosition > 0)
{
// if dataPosition does not equal zero, meaning we have some of a piece from the last file. This automatically fails,
// and we move onto the next piece.
i++;
fileDataLeft = fileLength - (this.infofile.GetPieceLength(0) - dataPosition);
}
else
{
fileDataLeft = fileLength - filePosition;
}
int numPieces = fileDataLeft / this.infofile.GetPieceLength(0);
i += numPieces;
if (fileDataLeft % this.infofile.GetPieceLength(0) > 0)
{
// set the next file's filePosition, and fail the next piece
filePosition = this.infofile.GetPieceLength(i) - (fileDataLeft % this.infofile.GetPieceLength(i));
i++;
}
else
{
filePosition = 0;
}
dataPosition = 0;
if (callback != null)
{
callback(this, i, false, ((float)(i + 1) / (float)this.infofile.PieceCount) * 100.0f);
}
// move onto next file
continue;
}
else
{
// check the length, otherwise truncate it
if (fileInfo.Length != fileLength)
{
this.TruncateFile(fileInfo, fileLength);
}
// open the file, start checking.
IO.FileStream fstream = fileInfo.OpenRead();
while (filePosition < fileLength)
{
int dataToRead = System.Math.Min(fileLength - filePosition, this.infofile.GetPieceLength(i) - dataPosition);
byte[] tempData = new byte[dataToRead];
fstream.Read(tempData, 0, tempData.Length);
if (dataToRead + dataPosition >= this.infofile.GetPieceLength(i))
{
// piece finished
System.Array.Copy(tempData, 0, data, dataPosition, dataToRead);
sha.ComputeHash(data, 0, this.infofile.GetPieceLength(i));
ByteField20 final = new ByteField20(sha.Hash);
bool good = final.Equals(this.infofile.GetSHADigest(i));
if (!good) // if piece is good we can subtract it from the bytes left to download
{
numBytesLeft += this.infofile.GetPieceLength(i);
}
this.piecesDownloaded.Set(i, good);
if (callback != null)
{
callback(this, i, good, ((float)(i + 1) / (float)this.infofile.PieceCount) * 100.0f);
}
i++;
dataPosition = 0;
}
else
{
System.Array.Copy(tempData, 0, data, dataPosition, dataToRead);
dataPosition += dataToRead;
}
filePosition += dataToRead;
}
filePosition = 0;
fstream.Close();
}
}
}
if (this.PercentChanged != null)
{
this.PercentChanged(this, this.PercentComplete);
}
}
/// <summary>
/// This *must* be called before any operations are performed. This should be in the constructor, but as it can be a time-consuming process
/// it was decided against. This analyzes the file to look for which pieces are downloaded, or if the torrent has just started it will create the
/// new, empty files.
/// </summary>
/// <param name="callback">Callback delegate to inform the caller of the progress</param>
public void CheckIntegrity( bool forced, CheckIntegrityCallback callback)
{
// if their already is a piece file in the application directory, load it from there. (unless it is forced where is has to do it)
if ( forced || !GetPieceInfoFromFile(callback))
{
int dataPosition = 0, filePosition = 0;
int i = 0;
byte[] data = new byte[this.infofile.GetPieceLength(0)];
Crypto.SHA1 sha = Crypto.SHA1CryptoServiceProvider.Create();
for (int currentFile=0; currentFile<this.infofile.FileCount; ++currentFile)
{
int fileLength = this.infofile.GetFileLength(currentFile);
string path = this.infofile.GetFileName(currentFile);
IO.FileInfo fileInfo = new IO.FileInfo(path);
if (!fileInfo.Exists)
{
// create the file if it does not exist
this.CreateEmptyFile(fileInfo, fileLength);
int fileDataLeft = 0;
if (dataPosition > 0)
{
// if dataPosition does not equal zero, meaning we have some of a piece from the last file. This automatically fails,
// and we move onto the next piece.
i++;
fileDataLeft = fileLength - (this.infofile.GetPieceLength(0) - dataPosition);
}
else
fileDataLeft = fileLength - filePosition;
int numPieces = fileDataLeft / this.infofile.GetPieceLength(0);
i += numPieces;
if (fileDataLeft % this.infofile.GetPieceLength(0) > 0)
{
// set the next file's filePosition, and fail the next piece
filePosition = this.infofile.GetPieceLength(i) - (fileDataLeft % this.infofile.GetPieceLength(i));
i++;
}
else
{
filePosition = 0;
}
dataPosition = 0;
if (callback != null)
callback(this, i, false, ((float)(i+1)/(float)this.infofile.PieceCount) * 100.0f);
// move onto next file
continue;
}
else
{
// check the length, otherwise truncate it
if (fileInfo.Length != fileLength)
this.TruncateFile(fileInfo, fileLength);
// open the file, start checking.
IO.FileStream fstream = fileInfo.OpenRead();
while (filePosition < fileLength)
{
int dataToRead = System.Math.Min(fileLength - filePosition, this.infofile.GetPieceLength(i) - dataPosition);
byte[] tempData = new byte[dataToRead];
fstream.Read(tempData, 0, tempData.Length);
if (dataToRead + dataPosition >= this.infofile.GetPieceLength(i))
{
// piece finished
System.Array.Copy(tempData, 0, data, dataPosition, dataToRead);
sha.ComputeHash(data, 0, this.infofile.GetPieceLength(i));
ByteField20 final = new ByteField20(sha.Hash);
bool good = final.Equals( this.infofile.GetSHADigest(i) );
if (!good) // if piece is good we can subtract it from the bytes left to download
numBytesLeft += this.infofile.GetPieceLength(i);
this.piecesDownloaded.Set(i, good);
if (callback != null)
callback(this, i, good, ((float)(i+1)/(float)this.infofile.PieceCount) * 100.0f);
i++;
dataPosition = 0;
}
else
{
System.Array.Copy(tempData, 0, data, dataPosition, dataToRead);
dataPosition += dataToRead;
}
filePosition += dataToRead;
}
filePosition = 0;
fstream.Close();
}
}
}
if (this.PercentChanged != null)
this.PercentChanged(this, this.PercentComplete);
}
private bool GetPieceInfoFromFile(CheckIntegrityCallback callback)
{
string pieceFilePath = Config.ApplicationDataDirectory + IO.Path.DirectorySeparatorChar + this.infofile.PieceFileName + ".piece";
IO.FileInfo pieceFileInfo = new IO.FileInfo(pieceFilePath);
if (pieceFileInfo.Exists)
{
// before we rely on the piece file, do a simple check of file existance and lengths to make sure nothing's changed
for (int i=0; i<this.infofile.FileCount; ++i)
{
string path = this.infofile.GetFileName(i);
int properLength = this.infofile.GetFileLength(i);
// TODO: introduce modification time check - requires saving time data in piece file
IO.FileInfo fileInfo = new IO.FileInfo(path);
if (!fileInfo.Exists)
return false; // a file doesn't exist, do a proper check
long realLength = fileInfo.Length;
if (properLength != realLength)
return false; // a file doesn't have a proper length, do a proper check
}
IO.FileStream pieceFile = pieceFileInfo.OpenRead();
int numBytes = this.infofile.PieceCount/8 + ((this.infofile.PieceCount % 8) > 0 ? 1 : 0);
byte[] data = new byte[numBytes];
pieceFile.Read(data, 0, data.Length);
pieceFile.Close();
this.piecesDownloaded.SetFromRaw( data, 0, data.Length );
this.piecesDownloaded.SetLength(this.infofile.PieceCount);
this.numBytesLeft = 0;
for (int i=0; i<this.infofile.PieceCount; ++i)
{
if (!this.piecesDownloaded[i])
this.numBytesLeft += this.infofile.GetPieceLength(i);
}
if (callback != null)
callback(this, this.infofile.PieceCount-1, false, 100.0f);
return true;
}
else
return false;
}