Result Par2Creator::Process(const CommandLine &commandline)
{
// Get information from commandline
noiselevel = commandline.GetNoiseLevel();
blocksize = commandline.GetBlockSize();
sourceblockcount = commandline.GetBlockCount();
const list<CommandLine::ExtraFile> extrafiles = commandline.GetExtraFiles();
sourcefilecount = (u32)extrafiles.size();
u32 redundancy = commandline.GetRedundancy();
recoveryblockcount = commandline.GetRecoveryBlockCount();
recoveryfilecount = commandline.GetRecoveryFileCount();
firstrecoveryblock = commandline.GetFirstRecoveryBlock();
recoveryfilescheme = commandline.GetRecoveryFileScheme();
string par2filename = commandline.GetParFilename();
size_t memorylimit = commandline.GetMemoryLimit();
largestfilesize = commandline.GetLargestSourceSize();
// Compute block size from block count or vice versa depending on which was
// specified on the command line
if (!ComputeBlockSizeAndBlockCount(extrafiles))
return eInvalidCommandLineArguments;
// Determine how many recovery blocks to create based on the source block
// count and the requested level of redundancy.
if (redundancy > 0 && !ComputeRecoveryBlockCount(redundancy))
return eInvalidCommandLineArguments;
// Determine how much recovery data can be computed on one pass
if (!CalculateProcessBlockSize(memorylimit))
return eLogicError;
// Determine how many recovery files to create.
if (!ComputeRecoveryFileCount())
return eInvalidCommandLineArguments;
if (noiselevel > CommandLine::nlQuiet)
{
// Display information.
cout << "Block size: " << blocksize << endl;
cout << "Source file count: " << sourcefilecount << endl;
cout << "Source block count: " << sourceblockcount << endl;
if (redundancy>0 || recoveryblockcount==0)
cout << "Redundancy: " << redundancy << '%' << endl;
cout << "Recovery block count: " << recoveryblockcount << endl;
cout << "Recovery file count: " << recoveryfilecount << endl;
cout << endl;
}
// Open all of the source files, compute the Hashes and CRC values, and store
// the results in the file verification and file description packets.
if (!OpenSourceFiles(extrafiles))
return eFileIOError;
// Create the main packet and determine the setid to use with all packets
if (!CreateMainPacket())
return eLogicError;
// Create the creator packet.
if (!CreateCreatorPacket())
return eLogicError;
// Initialise all of the source blocks ready to start reading data from the source files.
if (!CreateSourceBlocks())
return eLogicError;
// Create all of the output files and allocate all packets to appropriate file offets.
if (!InitialiseOutputFiles(par2filename))
return eFileIOError;
if (recoveryblockcount > 0)
{
// Allocate memory buffers for reading and writing data to disk.
if (!AllocateBuffers())
return eMemoryError;
// Compute the Reed Solomon matrix
if (!ComputeRSMatrix())
return eLogicError;
// Set the total amount of data to be processed.
progress = 0;
totaldata = blocksize * sourceblockcount * recoveryblockcount;
previouslyReportedFraction = -10000000; // Big negative
// Start at an offset of 0 within a block.
u64 blockoffset = 0;
while (blockoffset < blocksize) // Continue until the end of the block.
{
// Work out how much data to process this time.
size_t blocklength = (size_t)min((u64)chunksize, blocksize-blockoffset);
// Read source data, process it through the RS matrix and write it to disk.
if (!ProcessData(blockoffset, blocklength))
return eFileIOError;
blockoffset += blocklength;
}
if (noiselevel > CommandLine::nlQuiet)
cout << "Writing recovery packets" << endl;
// Finish computation of the recovery packets and write the headers to disk.
if (!WriteRecoveryPacketHeaders())
return eFileIOError;
// Finish computing the full file hash values of the source files
if (!FinishFileHashComputation())
return eLogicError;
}
// Fill in all remaining details in the critical packets.
if (!FinishCriticalPackets())
return eLogicError;
if (noiselevel > CommandLine::nlQuiet)
cout << "Writing verification packets" << endl;
// Write all other critical packets to disk.
if (!WriteCriticalPackets())
return eFileIOError;
// Close all files.
if (!CloseFiles())
return eFileIOError;
if (noiselevel > CommandLine::nlSilent)
cout << "Done" << endl;
return eSuccess;
}
// Determine how many recovery blocks to create based on the source block
// count and the requested level of redundancy.
bool Par2Creator::ComputeRecoveryBlockCount(u32 redundancy, u64 redundancysize)
{
if (redundancy > 0)
{
// Determine recoveryblockcount
recoveryblockcount = (sourceblockcount * redundancy + 50) / 100;
}
else if (redundancysize > 0)
{
bool closest = false;
u64 overhead;
overhead = sourceblockcount * 21;
u32 estimatedFileCount;
u64 totalOverhead;
do
{
if (recoveryfilecount == 0)
{
estimatedFileCount = 15;
}
else
{
closest = true;
estimatedFileCount = recoveryfilecount + 1;
}
totalOverhead = estimatedFileCount * overhead;
if (totalOverhead > redundancysize)
{
recoveryblockcount = 1;
}
else
{
recoveryblockcount = (redundancysize - totalOverhead) / (blocksize + 70);
}
ComputeRecoveryFileCount();
}
while(closest == false);
recoveryfilecount = 0;
}
else
{
cerr << "Redundancy and Redundancysize not set." << endl;
return false;
}
// Force valid values if necessary
if (recoveryblockcount == 0 && redundancy > 0)
recoveryblockcount = 1;
if (recoveryblockcount > 65536)
{
cerr << "Too many recovery blocks requested." << endl;
return false;
}
// Check that the last recovery block number would not be too large
if (firstrecoveryblock + recoveryblockcount >= 65536)
{
cerr << "First recovery block number is too high." << endl;
return false;
}
cout << endl;
return true;
}
