Change #261817

Comments

multi: improve wakeup and wait code
- Split WINSOCK and POSIX code in `multi_wait()` as the ifdef'ery
  was becoming unreadable
- define `ENABLE_WAKEUP` to mean the wakeup socketpair is enabled,
  no additional USE_WINSOCK check needed. Under WINSOCK
  `ENABLE_WAKEUP` is not defined, so it's availability is as before
  under the double defined() checks
- When the multi handle has "alive" transfers, the admin handle's
  pollset include the wakeup receive socket. This results in the
  admin handle running when someone uses `curl_multi_wakeup()`.
- Without any "alive" transfers, the wakeup socket is removed from
  the pollset. Otherwise, event based processing would never finish,
  eg. leave the event loop.
- The wakeup socket was never registered for event processing before,
  e.g. `curl_multi_wakeup()` never worked in that mode.
- Adjust test exepectations on socket callback invocations and
  number of sockets appearing in waitfds sets.

Closes #20832

Changed files

• lib/multi.c
• lib/multi_ev.c
• lib/multihandle.h
• tests/http/test_19_shutdown.py
• tests/libtest/lib2405.c
• tests/libtest/lib530.c
• tests/libtest/lib758.c