util/qemu-thread-posix.c: Replace OS ifdefs with CONFIG_HAVE_SEM_TIMEDWAIT

In qemu-thread-posix.c we have two implementations of the
various qemu_sem_* functions, one of which uses native POSIX
sem_* and the other of which emulates them with pthread conditions.
This is necessary because not all our host OSes support
sem_timedwait().

Instead of a hard-coded list of OSes which don't implement
sem_timedwait(), which gets out of date, make configure
test for the presence of the function and set a new
CONFIG_HAVE_SEM_TIMEDWAIT appropriately.

In particular, newer NetBSDs have sem_timedwait(), so this
commit will switch them over to using it. OSX still does
not have an implementation.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Kamil Rytarowski <n54@gmx.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>

1 files changed, 1 insertions, 1 deletions

diff --git a/include/qemu/thread-posix.h b/include/qemu/thread-posix.h
index e5e3a0ff97..f4296d31c4 100644
--- a/include/qemu/thread-posix.h
+++ b/include/qemu/thread-posix.h
@@ -21,7 +21,7 @@ struct QemuCond {
 };
 
 struct QemuSemaphore {
-#if defined(__APPLE__) || defined(__NetBSD__)
+#ifndef CONFIG_SEM_TIMEDWAIT
     pthread_mutex_t lock;
     pthread_cond_t cond;
     unsigned int count;