Exported functions in tests

[Zebediah Figura]

On 10/13/2017 02:16 AM, Hans Leidekker wrote:
> On Thu, 2017-10-12 at 23:09 -0500, Zebediah Figura wrote:
>> I was working on a test for MSI type 1 custom actions, i.e. functions
>> exported from a given DLL and called by the install script. I've tested
>> both with an independent file and in the Wine test environment, and I've
>> found that I can successfully export functions from the executable
>> itself with DECLSPEC_EXPORT, and MSI will successfully execute the
>> function, as the attached patch demonstrates.
>>
>> The function returns ERROR_SUCCESS, and changing this to other values
>> gets reflected in the install's error code appropriately. However, as
>> soon as I add a function call to the custom action, the install fails
>> with ERROR_INSTALL_FAILURE, and the function is never called—making it
>> look, in all probability, like a page fault occurred. This is the case
>> when compiling with mingw-w64, both inside the Wine test environment and
>> in an independent file.
>>
>> Notably I have no trouble calling DLLs taken from real MSI packages in
>> this way. I also have no trouble calling the function if I use
>> GetModuleHandle() and GetProcAddress() directly, nor do I run into any
>> trouble whatsoever running the custom action on Linux. It is
>> specifically this environment—running this function as part of a custom
>> action, on Windows.
> 
> Does it fail on any function call or just calls back into the test
> execu
> table? Can you call a kernel API? Perhaps it's some sort of
> protection
> scheme.
> 

It fails on any call into the API, so I have no way of checking if it's 
failing on internal function calls.