public MemoryMapper(string filePath, long initialFileSize)
{
try
{
if (initialFileSize <= 0 || initialFileSize % Constants.AllocationGranularity != 0)
{
throw new ArgumentException("The initial file size must be a multiple of 64Kb and grater than zero");
}
bool existingFile = File.Exists(filePath);
fs = new FileStream(filePath, FileMode.OpenOrCreate, FileAccess.ReadWrite, FileShare.None);
if (existingFile)
{
if (fs.Length <= 0 || fs.Length % Constants.AllocationGranularity != 0)
{
throw new ArgumentException("Invalid file. Its lenght must be a multiple of 64Kb and greater than zero");
}
}
else
{
fs.SetLength(initialFileSize);
}
mapping = MemoryMapping.Create(fs);
}
catch
{
Dispose();
throw;
}
}
public DataFile(string filePath, long initialSize, int growthIncrement)
{
try
{
bool isNew = !File.Exists(filePath);
memoryMapper = new MemoryMapper(filePath, initialSize);
mapping = MemoryMapping.Create(memoryMapper.fs, Constants.AllocationGranularity);
dataFileHeaderPointer = (DataFileHeader *)mapping.GetBaseAddress();
this.growthIncrement = (growthIncrement + Constants.AllocationGranularityMask) / Constants.AllocationGranularity * Constants.AllocationGranularity;
if (isNew)
{
InitializeHeader();
}
else
{
ValidateHeader();
}
}
catch
{
Dispose();
throw;
}
}
