[2/2] imagehlp: Implement ImageGetDigestStream

[Andrey Turkin]

On Saturday 17 July 2010 18:19:50 Dan Kegel wrote:
> I was worried that mapping the file will fail if you're
> low on address space and are running this function
> on a large PE file.
> It ought to be possible to write a test to see how
> the function behaves when you've used up oodles
> of address space, though it'd be tricky to make
> the test reliable.
> 
> I see that Windows has a similar problem in MapFileAndCheckSum
> (which is said to be a caller of this function)
> http://www.daniweb.com/forums/thread122484.html
> so who knows, maybe Windows also maps the file...

A good question; using mapped file seemed like a good idea (much easier to 
deal with than reading chunks explicitly) and, frankly speaking, I didn't 
thought about possible virtual address space shortage as a side-effect. 
Anyway, I tried ImageGetDigestStream with a big file on Vista and apparently 
it uses whole file map as well - no problem here.