IGlobalRSCAQueryProvider::ResizeOutputBuffer Method

Article
03/09/2018

Resizes and returns the output BYTE array.

Syntax

virtual HRESULT ResizeOutputBuffer(  
   DWORD cbNewBuffer,  
   DWORD cbBytesToCopy,  
   IN OUT BYTE** ppbBuffer  
) = 0;

Parameters

cbNewBuffer
[IN] A DWORD that contains the number of bytes to allocate.

cbBytesToCopy
[IN] A DWORD that contains the number of bytes to copy from ppbBuffer into the new buffer.

ppbBuffer
[IN][OUT] A pointer to a BYTE array that contains the new buffer.

Return Value

An HRESULT. Possible values include, but are not limited to, those in the following table.

Value	Definition
S_OK	Indicates that the operation was successful.
E_INVALIDARG	Indicates that `cbBytesToCopy` is greater than `cbNewBuffer`.
E_OUTOFMEMORY	Indicates that heap memory is exhausted.

Remarks

CGlobalModule derived classes that register for GL_RSCA_QUERY events receive an IGlobalRscaQueryProvider pointer as a parameter on the CGlobalModule::OnGlobalRSCAQueryvirtual method. You can then resize a current BYTE array by calling the ResizeOutputBuffer method on the IGlobalRSCAQueryProvider pointer.

The ResizeOutputBuffer return value depends on implementation. You should use the following information as a guideline, but it may not be correct in all scenarios:

The IGlobalRSCAQueryProvider implementer declares a private``BYTE pointer as a member variable called buffer; the implementer initializes buffer to NULL at construction. If the cbBytesToCopy parameter is greater than the cbNewBuffer parameter when ResizeOutputBuffer is called, ResizeOutputBuffer immediately returns E_INVALIDARG. Otherwise, the LocalAlloc function is called to create a new buffer of size cbNewBuffer, and the contents of the ppbBuffer parameter (up to the length of cbBytesToCopy) are copied into this new buffer. The LocalFree function is then called to dispose of the private buffer, which is reassigned to the new buffer. The private buffer is then returned in the dereferenced ppbBuffer parameter if ResizeOutputBuffer returns S_OK.

Important This method is part of the IIS 7 infrastructure and is not intended to be used directly from your code.

Notes for Implementers

IGlobalRSCAQueryProvider implementers are responsible for memory management with this data; therefore, IGlobalRSCAQueryProvider implementers that use dynamic memory allocation must release or call delete on the BYTE pointer when it is no longer needed.

Notes for Callers

IGlobalRSCAQueryProvider implementers are responsible for memory management with this data; therefore, IGlobalRSCAQueryProvider clients must not release or call delete on the returned BYTE pointer when this data is no longer needed.

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 Technical Preview
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