/// <summary>
/// Initialises the ImageFileHeader class and populates it with
/// the specific data from the file contents
/// </summary>
/// <param name="fileContents">The contents of the file being read as an array</param>
/// <param name="offset">The offset for the image file header</param>
public FileHeader(byte[] fileContents, Offset offset)
{
_machine = (MachineTypes)BitConverter.ToUInt16(fileContents, offset.Shift(2));
_numberOfSections = BitConverter.ToUInt16(fileContents, offset.Shift(2));
_timeDateStamp = BitConverter.ToUInt32(fileContents, offset.Shift(4));
_pointerToSymbolTable = BitConverter.ToUInt32(fileContents, offset.Shift(4));
_numberOfSymbols = BitConverter.ToUInt32(fileContents, offset.Shift(4));
_sizeOfOptionalHeader = BitConverter.ToUInt16(fileContents, offset.Shift(2));
_characteristics = (FileCharacteristics)BitConverter.ToUInt16(fileContents, offset.Shift(2));
}
/// <summary>
/// Returns the length of a specified file and the last time it has been written. File appender is queried before the file system.
/// </summary>
/// <param name="filePath">File which the information are requested.</param>
/// <returns>The file characteristics, if the file information was retrieved successfully, otherwise null.</returns>
private FileCharacteristics GetFileCharacteristics(string filePath)
{
var fileCharacteristics = this.fileAppenderCache.GetFileCharacteristics(filePath);
if (fileCharacteristics != null)
return fileCharacteristics;
var fileInfo = new FileInfo(filePath);
if (fileInfo.Exists)
{
#if !SILVERLIGHT
fileCharacteristics = new FileCharacteristics(fileInfo.CreationTimeUtc, fileInfo.LastWriteTimeUtc, fileInfo.Length);
#else
fileCharacteristics = new FileCharacteristics(fileInfo.CreationTime, fileInfo.LastWriteTime, fileInfo.Length);
#endif
return fileCharacteristics;
}
return null;
}
private bool PreviousLogOverlappedPeriod(FileCharacteristics fileCharacteristics, LogEventInfo logEvent)
{
if (!previousLogEventTimestamp.HasValue)
return false;
string formatString = GetArchiveDateFormatString(string.Empty);
string lastWriteTimeString = TimeSource.Current.FromSystemTime(fileCharacteristics.LastWriteTimeUtc).ToString(formatString, CultureInfo.InvariantCulture);
string logEventTimeString = logEvent.TimeStamp.ToString(formatString, CultureInfo.InvariantCulture);
if (lastWriteTimeString != logEventTimeString)
return false;
DateTime periodAfterPreviousLogEventTime;
switch (this.ArchiveEvery)
{
case FileArchivePeriod.Year: periodAfterPreviousLogEventTime = previousLogEventTimestamp.Value.AddYears(1); break;
case FileArchivePeriod.Month: periodAfterPreviousLogEventTime = previousLogEventTimestamp.Value.AddMonths(1); break;
case FileArchivePeriod.Day: periodAfterPreviousLogEventTime = previousLogEventTimestamp.Value.AddDays(1); break;
case FileArchivePeriod.Hour: periodAfterPreviousLogEventTime = previousLogEventTimestamp.Value.AddHours(1); break;
case FileArchivePeriod.Minute: periodAfterPreviousLogEventTime = previousLogEventTimestamp.Value.AddMinutes(1); break;
default: return false;
}
string periodAfterPreviousLogEventTimeString = periodAfterPreviousLogEventTime.ToString(formatString, CultureInfo.InvariantCulture);
return lastWriteTimeString == periodAfterPreviousLogEventTimeString;
}