[Bug 31051] New: HttpQueryInfo() erroneously ignores lpdwIndex argument for some info levels

[wine-bugs at winehq.org]

http://bugs.winehq.org/show_bug.cgi?id=31051

             Bug #: 31051
           Summary: HttpQueryInfo() erroneously ignores lpdwIndex argument
                    for some info levels
           Product: Wine
           Version: unspecified
          Platform: x86
        OS/Version: Linux
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: wininet
        AssignedTo: wine-bugs at winehq.org
        ReportedBy: support at tarma.com
    Classification: Unclassified


The HttpQueryInfo() function should return data based on both the dwInfoLevel
and the *lpdwIndex arguments (if the latter is specified). In particular,
*lpdwIndex may be used by the caller to enumerate multiple headers with the
same name, like this idiom:

/* ...various irrelevant details and other error handling omitted...*/
DWORD dwIndex = 0;
while (HttpQueryInfo(hRequest, dwInfoLevel, pBuffer, dwBufSize, &dwIndex)) {
    /* ...process the returned data... */
}

This enumerates potentially multiple like-named headers for the given
dwInfoLevel. It relies on HttpQueryInfo() to do the following (see Microsoft
Win32 API docs for HttpQueryInfo()):

(1) Check if the dwIndex-th header is available for dwInfoLevel; if not, return
FALSE and SetLastError(ERROR_HTTP_HEADER_NOT_FOUND).

(2) If the dwIndex-th header is available, then return its data (subject to
buffer space etc.) and increment *(&dwIndex).

For several of the possible dwInfoLevels, Wine's HttpQueryInfoW()
implementation has the following problems:

(P1) It does not check its *lpdwIndex value, but returns the same data and an
ERROR_SUCCESS result regardless of that value; and

(P2) It does not always increment *lpdwIndex if the current function call is
successful.

It keeps returning the same data regardless of the value of *lpdwIndex, and
keeps returning TRUE. This leads to infinite loops in the caller when used with
(variations of) the above enumeration idiom.

In particular, this erroneous behavior occurs with the following dwInfoLevels
(see implementation of HTTP_HttpQueryInfoW() in dlls\wininet\http.c):

HTTP_QUERY_RAW_HEADERS_CRLF:

EXPECTED: Should return data and increment *lpdwIndex for *lpdwIndex==0 only,
and return ERROR_HTTP_HEADER_NOT_FOUND for all other values of *lpdwIndex.

ACTUAL: Instead, always returns ERROR_SUCCESS except if the destination buffer
is too small. It also does not increment *lpdwIndex if it returns
ERROR_SUCCESS.

HTTP_QUERY_RAW_HEADERS: (ditto)
HTTP_QUERY_STATUS_TEXT: (ditto)
HTTP_QUERY_VERSION: (ditto)

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