ISAPI Filter DLL - OnUrlMap is called multiple times   

Hi everyone,

I wrote a ISAPI filter DLL to process text/html content. Whenever there's a 
request for a .php file, the OnUrlMap gets called 3 times whereas .html or 
..asp files causes the right behaviour in Filter (i.e. - OnUrlMap gets called 
once only). How do I get rid off this problem? Below is the excerpt of the 
code -

DWORD OnSendRawData(...) {
  //Process pvRawData....
  ........
  //Writes HTTP HEADER to client
  pfc->WriteClient(....);
  //Writes BODY
  //pfc->WriteClient(...);
}

When the code executes for HTTP HEADER, the function gets suspended and the 
second request of the .php file calls OnSendRawData. When any Win32 API gets 
called in the OnSendRawData code, the second request is suspended and the 
first one is resumed (i.e.- starts writing the BODY).

As both are same actually request, it messed up the private (or content 
specific) data.

So, How to stop multiple request in OnUrlMap?

date: Sat, 11 Mar 2006 09:24:26 -0800   author:   Shoily Obaidur Rahman Shoily Obaidur

Re: ISAPI Filter DLL - OnUrlMap is called multiple times   

The behaviors you describe are all by-design.

http://blogs.msdn.com/david.wang/archive/2006/03/11/Why_some_ISAPI_Filter_events_trigger_multiple_times_per_request.aspx

-- 
//David
IIS
http://blogs.msdn.com/David.Wang
This posting is provided "AS IS" with no warranties, and confers no rights.
//

"Shoily Obaidur Rahman" <Shoily Obaidur Rahman@discussions.microsoft.com> 
wrote in message news:820D6BAE-C86B-4785-A8AF-B89DE39F2496@microsoft.com...
> Hi everyone,
>
> I wrote a ISAPI filter DLL to process text/html content. Whenever there's 
> a
> request for a .php file, the OnUrlMap gets called 3 times whereas .html or
> .asp files causes the right behaviour in Filter (i.e. - OnUrlMap gets 
> called
> once only). How do I get rid off this problem? Below is the excerpt of the
> code -
>
> DWORD OnSendRawData(...) {
>  //Process pvRawData....
>  ........
>  //Writes HTTP HEADER to client
>  pfc->WriteClient(....);
>  //Writes BODY
>  //pfc->WriteClient(...);
> }
>
> When the code executes for HTTP HEADER, the function gets suspended and 
> the
> second request of the .php file calls OnSendRawData. When any Win32 API 
> gets
> called in the OnSendRawData code, the second request is suspended and the
> first one is resumed (i.e.- starts writing the BODY).
>
> As both are same actually request, it messed up the private (or content
> specific) data.
>
> So, How to stop multiple request in OnUrlMap?
>
>

date: Sun, 12 Mar 2006 05:41:31 -0800   author:   David Wang [Msft]