private char[] GetNextLine(Common.Random random, long capacity, ref List <char[]> duplicates)
{
char[] chars = null;
if (duplicates.Count > 0 && random.Next(100) < duplicatesProbabilityPercents)
{
//get duplicate line
chars = duplicates[random.Next(duplicates.Count)];
var remainingBytes = capacity - chars.Length;
if (remainingBytes <= MinLineLength)
{
chars = null;
}
}
// need to generate new line
if (null == chars)
{
// generate new line
var rnd = random.Next(MinLineLength, maxLineLength);
var length = Math.Min(rnd, capacity);
var remainingBytes = capacity - length;
if (remainingBytes <= MinLineLength)
{
length += remainingBytes;
}
chars = GenerateLine(random, (int)length);
// store duplicates to future use
if (duplicatePatternsCount > 0)
{
lock (duplicates)
{
--duplicatePatternsCount;
duplicates.Add(chars);
}
}
}
return(chars);
}
private static char[] GenerateLine(Common.Random random, int length)
{
var buffer = new char[length];
var dotIndex = random.Next(1, Math.Min(length - MinLineLength + 1, MaxDigitsConunt));
for (var i = 0; i < buffer.Length - 2; i++)
{
if (i == dotIndex || i == dotIndex + 1)
{
continue;
}
buffer[i] = chars[
i < dotIndex
? random.Next(i == 0 ? 1 : 0, 10)
: random.Next(chars.Length)];
}
buffer[dotIndex] = '.';
buffer[dotIndex + 1] = ' ';
buffer[buffer.Length - 2] = '\r';
buffer[buffer.Length - 1] = '\n';
return(buffer);
}
protected override void OnExecute()
{
Console.WriteLine("=========================================================");
Console.WriteLine("System.Security.Cryptography.RNGCryptoServiceProvider takes much more time but ensures pure random!");
Console.WriteLine("To increase performance please provide 'UseSystemRandom = true' in command but it can cause unpredictable duplicates!!!");
// avarage duplicates probabilty.
var duplicates = new List <char[]>();
var totalLinesCount = 0;
file = LargeFile.Create(fileName, fileSize);
var parts = file.Write().ToArray();
if (parts.Length > 1)
{
Console.WriteLine($"File generation is devided onto {parts.Length} parts.");
}
var random = new Common.Random(useSystemRandom);
for (var i = 0; i < parts.Length; ++i)
{
if (parts.Length > 1)
{
Console.WriteLine($"Generating Part({i})...");
}
var progress = new Progress();
parts[i].Process((stream, block, cancel) =>
{
var bytesWritten = 0;
while (!cancel.IsCancellationRequested && bytesWritten < stream.Length)
{
var chars = GetNextLine(random, stream.Length - bytesWritten, ref duplicates);
// use ASCII encoding for simplification
var buffer = Encoding.ASCII.GetBytes(chars);
stream.Write(buffer, 0, buffer.Length);
bytesWritten += buffer.Length;
progress.Report((double)bytesWritten / stream.Length);
Interlocked.Increment(ref totalLinesCount);
}
if (block.Id == 0)
{
Console.WriteLine("Flushing streams, please wait...");
}
});
}
Console.WriteLine($"Total lines count: {totalLinesCount}");
if (file.IsCancelled)
{
// delete file due to process was cacelled
if (File.Exists(fileName))
{
File.Delete(fileName);
Console.WriteLine("Process terminated");
Console.WriteLine("File system has been cleaned.");
Console.WriteLine("Press any key...");
Console.ReadLine();
}
}
}
