bug#22789: 25.1.50; In last master build https connections stop working

[Alain Schneble <a.s@realize.ch>]

Lars Ingebrigtsen <larsi@gnus.org> writes:

> Eli Zaretskii <eliz@gnu.org> writes:
>
>> So what you can do instead of launching a timer is this: as long as
>> some process waits for some sync stuff to complete, reduce the timeout
>> with which we call 'pselect' to some reasonably small value, like half
>> a second or maybe 0.25 sec.  This will ensure the loop doesn't stop as
>> long as we wait for at least one such connection.  (This will need a
>> simple logic to not exit the loop too early; see the variable
>> timeout_reduced_for_timers for a similar logic we employ already for
>> timers.)
>
> Aha!  With the following (for debugging purposes only) patch, it looks
> like I'm getting progress on my https connections even if I don't have a
> blinking cursor.  (I chose 50ms as my timeout, if I counted my zeroes
> correctly...)  Were you thinking about something along these lines?  If
> so, I can clean the patch up...

I was debugging it further and AFAICS, there must also be an issue in
shr with the processing of images.  Because without any patch, if all
the images were loaded properly, i.e. the shr-image-fetched callback in
shr.el was invoked for each of the images in a page, the images are
sometimes not displayed.

In shr.el shr-image-fetched, if I comment the line...
(url-store-in-cache image-buffer)
...then images are never shown.  Strange, not?  Or is this expected?

And now, even with ordinary http connections, if I delete
~/.emacs.d/url/cache, no images are displayed the first time I load the
page.

Did I mess up something with my build/installation?