maxRequestLength - behind the scene details needed! - asp.net

Question

What really happens to the currently executing request in IIS during a file upload, when the upload length exceed configured maxRequestLength.
Tried hard to find a decent article that talks about that, but there are none!!
Thanks

Answer 1

This is what exactly happens:
In class HttpRequest and in method GetEntireRawContent this condition is checked and will throw an exception:
if (length > maxRequestLengthBytes)
{
throw new HttpException(System.Web.SR.GetString("Max_request_length_exceeded"), null, 0xbbc);
}
Here is the whole of the method if you find useful:
private HttpRawUploadedContent GetEntireRawContent()
{
if (this._wr == null)
{
return null;
}
if (this._rawContent == null)
{
HttpRuntimeSection httpRuntime = RuntimeConfig.GetConfig(this._context).HttpRuntime;
int maxRequestLengthBytes = httpRuntime.MaxRequestLengthBytes;
if (this.ContentLength > maxRequestLengthBytes)
{
if (!(this._wr is IIS7WorkerRequest))
{
this.Response.CloseConnectionAfterError();
}
throw new HttpException(System.Web.SR.GetString("Max_request_length_exceeded"), null, 0xbbc);
}
int requestLengthDiskThresholdBytes = httpRuntime.RequestLengthDiskThresholdBytes;
HttpRawUploadedContent data = new HttpRawUploadedContent(requestLengthDiskThresholdBytes, this.ContentLength);
byte[] preloadedEntityBody = this._wr.GetPreloadedEntityBody();
if (preloadedEntityBody != null)
{
this._wr.UpdateRequestCounters(preloadedEntityBody.Length);
data.AddBytes(preloadedEntityBody, 0, preloadedEntityBody.Length);
}
if (!this._wr.IsEntireEntityBodyIsPreloaded())
{
int num3 = (this.ContentLength > 0) ? (this.ContentLength - data.Length) : 0x7fffffff;
HttpApplication applicationInstance = this._context.ApplicationInstance;
byte[] buffer = (applicationInstance != null) ? applicationInstance.EntityBuffer : new byte[0x2000];
int length = data.Length;
while (num3 > 0)
{
int size = buffer.Length;
if (size > num3)
{
size = num3;
}
int bytesIn = this._wr.ReadEntityBody(buffer, size);
if (bytesIn <= 0)
{
break;
}
this._wr.UpdateRequestCounters(bytesIn);
this.NeedToInsertEntityBody = true;
data.AddBytes(buffer, 0, bytesIn);
num3 -= bytesIn;
length += bytesIn;
if (length > maxRequestLengthBytes)
{
throw new HttpException(System.Web.SR.GetString("Max_request_length_exceeded"), null, 0xbbc);
}
}
}
data.DoneAddingBytes();
if ((this._installedFilter != null) && (data.Length > 0))
{
try
{
try
{
this._filterSource.SetContent(data);
HttpRawUploadedContent content2 = new HttpRawUploadedContent(requestLengthDiskThresholdBytes, data.Length);
HttpApplication application2 = this._context.ApplicationInstance;
byte[] buffer3 = (application2 != null) ? application2.EntityBuffer : new byte[0x2000];
while (true)
{
int num7 = this._installedFilter.Read(buffer3, 0, buffer3.Length);
if (num7 == 0)
{
break;
}
content2.AddBytes(buffer3, 0, num7);
}
content2.DoneAddingBytes();
data = content2;
}
finally
{
this._filterSource.SetContent(null);
}
}
catch
{
throw;
}
}
this._rawContent = data;
}
return this._rawContent;
}