CHttpFile::QueryInfo() returns "corrupted" CStrings with invalid lengths.

CHttpFile::QueryInfo() returns "corrupted" CStrings with invalid lengths. by ijprest

Closed

as Fixed

Type:	Bug
ID:	773448
Opened:	12/4/2012 12:15:00 PM
Access Restriction:	Public

Workaround(s)

view

User(s) can reproduce this bug

The implementation of the CString form of CHttpFile::QueryInfo() calls HttpQueryInfo to determine how big a buffer to allocate, which is always reported in bytes.

Since CHttpFile::QueryInfo() neglects to divide by sizeof(TCHAR), it ends up allocating a buffer twice as big as necessary in UNICODE builds.

When CHttpFile::QueryInfo() subsequently calls ReleaseBuffer() on the CString, it again specifies the incorrect size. As a result, the CString thinks it's bigger than it actually is, and cannot be used normally (e.g., in CString contenation scenarios).

Details (expand)

Visual Studio 2012

The following code snippet demonstrates the problem. (Compile w/UNICODE enabled)
---------------
CInternetSession session;
CHttpConnection* pConnection = session.GetHttpConnection(L"www.microsoft.com");
CHttpFile* pFile = pConnection->OpenRequest(L"GET", L"/");
pFile->SendRequest();

CString str;
pFile->QueryInfo(HTTP_QUERY_STATUS_TEXT, str);

CString message = CString(L"The status code '") + str + CString(L"' was received from the server.");
int length = str.GetLength();
------------------------

English

Windows 7

English

message == "The status code 'OK"
length == 4

message == "The status code 'OK' was received from the server."
length == 2

File Name	Submitted By	Submitted On	File Size
httpfiletest.zip	ijprest	12/5/2012	16 KB

Posted by Microsoft on 12/7/2012 at 12:54 AM

Hi ijprest, thanks for your response, we have received your demo project.
Thank you for submitting feedback on Visual Studio and .NET Framework. Your issue has been routed to the appropriate VS development team for investigation. We will contact you if we require any additional information.

Posted by ijprest on 12/5/2012 at 9:22 AM

I have attached a demo project (I think).

Posted by Microsoft on 12/4/2012 at 11:02 PM

Thank you for submitting feedback on Visual Studio and .NET Framework. In order to efficiently investigate and reproduce this issue, we are requesting a demo project. Please submit this information to us within 3 business days. We look forward to hearing from you with this information.

Posted by Microsoft on 12/4/2012 at 12:51 PM

Thank you for your feedback, we are currently reviewing the issue you have submitted. If this issue is urgent, please contact support directly(http://support.microsoft.com)