public IEnumerable <FileSegment> LoadSegments()
{
using (var stream = File.Open(_info.FullName, FileMode.Open, FileAccess.Read, FileShare.Delete | FileShare.ReadWrite))
{
var fileLength = stream.Length;
stream.Seek(0, SeekOrigin.Begin);
using (var reader = new StreamReaderExtended(stream, true))
{
if (reader.EndOfStream || fileLength == 0)
{
yield return(new FileSegment(0, 0, 0, FileSegmentType.Tail));
yield break;
}
if (fileLength < _initialTail)
{
yield return(new FileSegment(0, 0, fileLength, FileSegmentType.Tail));
yield break;
}
var headStartsAt = reader.FindNextEndOfLinePosition(fileLength - _initialTail);
long currentEnfOfPage = 0;
long previousEndOfPage = 0;
int index = 0;
do
{
var approximateEndOfPage = currentEnfOfPage + _segmentSize;
if (approximateEndOfPage >= headStartsAt)
{
yield return(new FileSegment(index, previousEndOfPage, headStartsAt, FileSegmentType.Head));
break;
}
currentEnfOfPage = reader.FindNextEndOfLinePosition(approximateEndOfPage);
yield return(new FileSegment(index, previousEndOfPage, currentEnfOfPage, FileSegmentType.Head));
index++;
previousEndOfPage = currentEnfOfPage;
} while (true);
index++;
yield return(new FileSegment(index, headStartsAt, fileLength, FileSegmentType.Tail));
}
}
}
public IEnumerable<FileSegment> LoadSegments()
{
using (var stream = File.Open(_info.FullName, FileMode.Open, FileAccess.Read,FileShare.Delete | FileShare.ReadWrite))
{
var fileLength = stream.Length;
stream.Seek(0, SeekOrigin.Begin);
using (var reader = new StreamReaderExtended(stream, true))
{
if (reader.EndOfStream || fileLength == 0)
{
yield return new FileSegment(0, 0, 0, FileSegmentType.Tail);
yield break;
}
if (fileLength < _initialTail)
{
yield return new FileSegment(0, 0, fileLength, FileSegmentType.Tail);
yield break;
}
var headStartsAt = reader.FindNextEndOfLinePosition(fileLength - _initialTail);
long currentEnfOfPage = 0;
long previousEndOfPage = 0;
int index = 0;
do
{
var approximateEndOfPage = currentEnfOfPage + _segmentSize;
if (approximateEndOfPage >= headStartsAt)
{
yield return new FileSegment(index, previousEndOfPage, headStartsAt, FileSegmentType.Head);
break;
}
currentEnfOfPage = reader.FindNextEndOfLinePosition(approximateEndOfPage);
yield return new FileSegment(index, previousEndOfPage, currentEnfOfPage, FileSegmentType.Head);
index++;
previousEndOfPage = currentEnfOfPage;
} while (true);
index ++;
yield return new FileSegment(index, headStartsAt, fileLength, FileSegmentType.Tail);
}
}
}
