IHttpContext::GetExecuteFlags Method

Article
06/14/2022

Retrieves the execution flags for the current context.

Syntax

virtual DWORD GetExecuteFlags(  
   VOID  
) const = 0;

Parameters

This method takes no parameters.

Return Value

A DWORD that contains the execution flags.

Remarks

The GetExecuteFlags method retrieves the execution flags for the current context. The following table lists the possible values for these flags.

Value	Description
EXECUTE_FLAG_NO_HEADERS	Suppress the HTTP headers for the child request.
EXECUTE_FLAG_IGNORE_CURRENT_INTERCEPTOR	Ignore the current script map handler for this request chain.
EXECUTE_FLAG_IGNORE_APPPOOL	Execute the request even if the child request is not in the same application pool.
EXECUTE_FLAG_DISABLE_CUSTOM_ERROR	Disable custom errors for the child request.
EXECUTE_FLAG_SAME_URL	The URL for the child request is the same as the parent request.
EXECUTE_FLAG_BUFFER_RESPONSE	Do not flush the child response; return the response to the parent request.
EXECUTE_FLAG_HTTP_CACHE_ELIGIBLE	The child response is still eligible for caching by Http.sys.

Example

The following code example demonstrates how to create an HTTP module that performs the following tasks:

The module registers for the RQ_SEND_RESPONSE notification.
The module creates a CHttpModule class that contains an OnSendResponse method.
When a Web client requests a URL, IIS calls the module's OnSendResponse method. This method performs the following tasks:
1. Clears the existing response buffer and sets the MIME type for the response.
2. Retrieves the execution flags for the current context by using the GetExecuteFlags method.
3. Tests for individual execution flags and returns the status to the Web client.
The module removes the CHttpModule class from memory and then exits.

#define _WINSOCKAPI_
#include <windows.h>
#include <sal.h>
#include <httpserv.h>

// Create the module class.
class MyHttpModule : public CHttpModule
{
public:
    REQUEST_NOTIFICATION_STATUS
    OnSendResponse(
        IN IHttpContext * pHttpContext,
        IN ISendResponseProvider * pProvider
    )
    {
        UNREFERENCED_PARAMETER( pProvider );
        
        // Clear the existing response.
        pHttpContext->GetResponse()->Clear();
        // Set the MIME type to plain text.
        pHttpContext->GetResponse()->SetHeader(
            HttpHeaderContentType,"text/plain",
            (USHORT)strlen("text/plain"),TRUE);

        WriteResponseMessage(pHttpContext,"Execute Flags:\n");

        // Retrieve the execution flags.
        DWORD dwExecuteFlags = pHttpContext->GetExecuteFlags();

        // Test for any flags.
        if (dwExecuteFlags == 0)
        {
            // Return a generic status if no flags are set.
            WriteResponseMessage(pHttpContext,"N/A\n");
        }
        // Test for individual flags and return them to a Web client.
        else
        {
            if (dwExecuteFlags & EXECUTE_FLAG_NO_HEADERS)
                WriteResponseMessage(pHttpContext,
                "EXECUTE_FLAG_NO_HEADERS\n");
            if (dwExecuteFlags & EXECUTE_FLAG_IGNORE_CURRENT_INTERCEPTOR)
                WriteResponseMessage(pHttpContext,
                "EXECUTE_FLAG_IGNORE_CURRENT_INTERCEPTOR\n");
            if (dwExecuteFlags & EXECUTE_FLAG_IGNORE_APPPOOL)
                WriteResponseMessage(pHttpContext,
                "EXECUTE_FLAG_IGNORE_APPPOOL\n");
            if (dwExecuteFlags & EXECUTE_FLAG_DISABLE_CUSTOM_ERROR)
                WriteResponseMessage(pHttpContext,
                "EXECUTE_FLAG_DISABLE_CUSTOM_ERROR\n");
            if (dwExecuteFlags & EXECUTE_FLAG_SAME_URL)
                WriteResponseMessage(pHttpContext,
                "EXECUTE_FLAG_SAME_URL\n");
            if (dwExecuteFlags & EXECUTE_FLAG_BUFFER_RESPONSE)
                WriteResponseMessage(pHttpContext,
                "EXECUTE_FLAG_BUFFER_RESPONSE\n");
            if (dwExecuteFlags & EXECUTE_FLAG_HTTP_CACHE_ELIGIBLE)
                WriteResponseMessage(pHttpContext,
                "EXECUTE_FLAG_HTTP_CACHE_ELIGIBLE\n");
        }

        // Return processing to the pipeline.
        return RQ_NOTIFICATION_FINISH_REQUEST;
    }

private:

    // Create a utility method that inserts a string value into the response.
    HRESULT WriteResponseMessage(
        IHttpContext * pHttpContext,
        PCSTR pszBuffer
    )
    {
        // Create an HRESULT to receive return values from methods.
        HRESULT hr;
        
        // Create a data chunk.
        HTTP_DATA_CHUNK dataChunk;
        // Set the chunk to a chunk in memory.
        dataChunk.DataChunkType = HttpDataChunkFromMemory;
        // Buffer for bytes written of data chunk.
        DWORD cbSent;

        // Set the chunk to the buffer.
        dataChunk.FromMemory.pBuffer =
            (PVOID) pszBuffer;
        // Set the chunk size to the buffer size.
        dataChunk.FromMemory.BufferLength =
            (USHORT) strlen(pszBuffer);
        // Insert the data chunk into the response.
        hr = pHttpContext->GetResponse()->WriteEntityChunks(
            &dataChunk,1,FALSE,TRUE,&cbSent);
        // Test for an error.
        if (FAILED(hr))
        {
            // Return the error status.
            return hr;
        }

        // Return a success status.
        return S_OK;
    }
};

// Create the module's class factory.
class MyHttpModuleFactory : public IHttpModuleFactory
{
public:
    HRESULT
    GetHttpModule(
        OUT CHttpModule ** ppModule, 
        IN IModuleAllocator * pAllocator
    )
    {
        UNREFERENCED_PARAMETER( pAllocator );

        // Create a new instance.
        MyHttpModule * pModule = new MyHttpModule;

        // Test for an error.
        if (!pModule)
        {
            // Return an error if we cannot create the instance.
            return HRESULT_FROM_WIN32( ERROR_NOT_ENOUGH_MEMORY );
        }
        else
        {
            // Return a pointer to the module.
            *ppModule = pModule;
            pModule = NULL;
            // Return a success status.
            return S_OK;
        }            
    }

    void Terminate()
    {
        // Remove the class from memory.
        delete this;
    }
};

// Create the module's exported registration function.
HRESULT
__stdcall
RegisterModule(
    DWORD dwServerVersion,
    IHttpModuleRegistrationInfo * pModuleInfo,
    IHttpServer * pGlobalInfo
)
{
    UNREFERENCED_PARAMETER( dwServerVersion );
    UNREFERENCED_PARAMETER( pGlobalInfo );

    return pModuleInfo->SetRequestNotifications(
        new MyHttpModuleFactory,
        RQ_SEND_RESPONSE,
        0
    );
}

Your module must export the RegisterModule function. You can export this function by creating a module definition (.def) file for your project, or you can compile the module by using the /EXPORT:RegisterModule switch. For more information, see Walkthrough: Creating a Request-Level HTTP Module By Using Native Code.

You can optionally compile the code by using the __stdcall (/Gz) calling convention instead of explicitly declaring the calling convention for each function.

Requirements

Type	Description
Client	- IIS 7.0 on Windows Vista - IIS 7.5 on Windows 7 - IIS 8.0 on Windows 8 - IIS 10.0 on Windows 10
Server	- IIS 7.0 on Windows Server 2008 - IIS 7.5 on Windows Server 2008 R2 - IIS 8.0 on Windows Server 2012 - IIS 8.5 on Windows Server 2012 R2 - IIS 10.0 on Windows Server 2016
Product	- IIS 7.0, IIS 7.5, IIS 8.0, IIS 8.5, IIS 10.0 - IIS Express 7.5, IIS Express 8.0, IIS Express 10.0
Header	Httpserv.h

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