private void SendFileContent(File422 file, WebRequest req)
{
byte[] buffer = new byte[1024]; //1kb buffer
StringBuilder sb = new StringBuilder();
string contentType; //default contentType
string status = "200 Success"; //default status
int initialPos;
long contentLength, startByte = 0;
//find extension
if (!exts.TryGetValue(Path.GetExtension(file.Name).ToLower(),
out contentType))
{
//default
contentType = "application/octet-stream";
}
using (Stream fs = file.OpenReadOnly()){
contentLength = fs.Length;
//if client sent a range request.
if (req.Headers.ContainsKey("range"))
{
var t = req.GetRangeHeader(fs.Length);
//find range
if (t == null)
{
string pageHTML = "<html><h1>416 REQUESTED RANGE NOT SATISFIABLE</h1></html>";
req.WriteRangeNotSatisfiableResponse(pageHTML,
fs.Length.ToString());
return;
}
status = "206 Partial Content";
startByte = t.Item1; //start offset byte
contentLength = (t.Item2 - t.Item1) + 1; //because contentLength is the length, not last byte.
}
sb.Append("HTTP/1.1 " + status + "\r\n");
sb.Append("Content-Length: " + contentLength + "\r\n");
sb.Append("Content-Type: " + contentType + "\r\n");
//we need this so that the file downloads, instead
//of trying to switch views.
/*sb.Append("Content-Disposition: attachment; filename=\"" +
* file.Name + "\"\r\n");*/
sb.Append("\r\n");
initialPos = sb.Length;
ASCIIEncoding.ASCII.GetBytes(sb.ToString()).CopyTo(buffer, 0);
if (req.Headers.ContainsKey("range"))
{
int totalBytesRead;
int bytesRead = 0;
//seek to startbyte.
fs.Seek(startByte, SeekOrigin.Begin);
//our initial read has to be the smaller of one of these 2.
int initialRead = ((buffer.Length - initialPos) < contentLength)
? buffer.Length - initialPos
: (int)contentLength; // if (buffer.Length - initialPos) >= cL
totalBytesRead = fs.Read(buffer, initialPos, initialRead);
//Console.WriteLine(ASCIIEncoding.ASCII.GetString(buffer));
//has to be what we had initially plus what we just read.
req.WriteResponse(buffer, initialPos + initialRead);
Array.Clear(buffer, 0, buffer.Length);
//if we still have not read up to content length, keep reading.
if (totalBytesRead < contentLength)
{
int subsequentRead = (buffer.Length < contentLength)
? buffer.Length
: (int)contentLength; // if (buffer.Length - initialPos) >= cL
//keep track of previous total bytes
int prevTotalBytesRead = totalBytesRead;
while ((bytesRead = fs.Read(buffer, 0, subsequentRead)) != 0 &&
(totalBytesRead += bytesRead) < contentLength)
{
prevTotalBytesRead = totalBytesRead;
req.WriteResponse(buffer, bytesRead);
Array.Clear(buffer, 0, buffer.Length);
}
if (totalBytesRead >= contentLength)
{
//we subtract the value of totalBytes right before it was more than contentLength,
//from content length (contentLength - prevTotalBytesRead)
//this gives us the last bit we need to write to achieve the range requested's length.
req.WriteResponse(buffer, (int)contentLength - prevTotalBytesRead);
}
}
}
else
{
fs.Read(buffer, initialPos, buffer.Length - initialPos);
req.WriteResponse(buffer);
while (fs.Read(buffer, 0, buffer.Length) != 0)
{
req.WriteResponse(buffer);
Array.Clear(buffer, 0, buffer.Length);
}
}
req.CloseResponse();
}
}