win: Explain the CreateFile() client-side pipe-opening loop

win: Explain the CreateFile() client-side pipe-opening loop

The bug and linked code review has more of the history, but we’ve been
tempted to remove the loop outright a couple of times already before
realizing that it serves an important purpose. Hopefully this comment
will protect our future selves from going on the same fool’s errand.

BUG=crashpad:75
R=scottmg@chromium.org

Committed: https://chromium.googlesource.com/crashpad/crashpad/+/7413569ea648a43200798fbc1b2a4730122905a1

[Mark Mentovai, 2015-11-10 19:55:51]

mark@chromium.org changed reviewers:
+ scottmg@chromium.org

[scottmg, 2015-11-10 20:02:20]

lgtm

https://codereview.chromium.org/1427643010/diff/20001/util/win/registration_p...
File util/win/registration_protocol_win.cc (left):

https://codereview.chromium.org/1427643010/diff/20001/util/win/registration_p...
util/win/registration_protocol_win.cc:68: LOG(ERROR) << "TransactNamedPipe:
expected " << sizeof(*response)
Duh, oops.

https://codereview.chromium.org/1427643010/diff/20001/util/win/registration_p...
File util/win/registration_protocol_win.cc (right):

https://codereview.chromium.org/1427643010/diff/20001/util/win/registration_p...
util/win/registration_protocol_win.cc:33: // user-mode code.
You could maybe also note that this means we don't retry in order to
pseudo-synchronize startup -- if the server-side pipe hasn't been created yet,
we'll just fail and return false.

[Mark Mentovai, 2015-11-10 20:10:15]

Patchset #3 (id:40001) has been deleted

[Mark Mentovai, 2015-11-10 20:10:50]

Patchset #3 (id:60001) has been deleted

[Mark Mentovai, 2015-11-10 20:11:36]

Patchset #3 (id:80001) has been deleted

[Mark Mentovai, 2015-11-10 20:12:20]

https://codereview.chromium.org/1427643010/diff/20001/util/win/registration_p...
File util/win/registration_protocol_win.cc (right):

https://codereview.chromium.org/1427643010/diff/20001/util/win/registration_p...
util/win/registration_protocol_win.cc:33: // user-mode code.
scottmg wrote:
> You could maybe also note that this means we don't retry in order to
> pseudo-synchronize startup -- if the server-side pipe hasn't been created yet,
> we'll just fail and return false.

Good call! Updated.

[scottmg, 2015-11-10 20:35:25]

lgtm!

[Mark Mentovai, 2015-11-10 21:43:18]

Committed patchset #3 (id:100001) manually as
7413569ea648a43200798fbc1b2a4730122905a1 (presubmit successful).