win32: Fix meson build system for Windows.

Part-of: <https://gitlab.freedesktop.org/pulseaudio/pulseaudio/-/merge_requests/360>

src/meson.build

@@ -39,7 +39,6 @@ libpulsecommon_sources = [
   'pulsecore/memblock.c',
   'pulsecore/memblockq.c',
   'pulsecore/memchunk.c',
-  'pulsecore/mutex-posix.c',
   'pulsecore/native-common.c',
   'pulsecore/once.c',
   'pulsecore/packet.c',
@@ -56,7 +55,6 @@ libpulsecommon_sources = [
   'pulsecore/random.c',
   'pulsecore/srbchannel.c',
   'pulsecore/sample-util.c',
-  'pulsecore/semaphore-posix.c',
   'pulsecore/shm.c',
   'pulsecore/bitset.c',
   'pulsecore/socket-client.c',
@@ -65,7 +63,6 @@ libpulsecommon_sources = [
   'pulsecore/strbuf.c',
   'pulsecore/strlist.c',
   'pulsecore/tagstruct.c',
-  'pulsecore/thread-posix.c',
   'pulsecore/time-smoother.c',
   'pulsecore/tokenizer.c',
   'pulsecore/usergroup.c',
@@ -177,6 +174,20 @@ if x11_dep.found()
 endif
 
 # FIXME: Do non-POSIX thread things
+if host_machine.system() == 'windows'
+  libpulsecommon_sources += [
+    'pulsecore/mutex-win32.c',
+    'pulsecore/poll-win32.c',
+    'pulsecore/semaphore-win32.c',
+    'pulsecore/thread-win32.c',
+  ]
+else
+  libpulsecommon_sources += [
+    'pulsecore/mutex-posix.c',
+    'pulsecore/semaphore-posix.c',
+    'pulsecore/thread-posix.c'
+  ]
+endif
 # FIXME: Do SIMD things
 
 libpulsecommon = shared_library('pulsecommon-' + pa_version_major_minor,
@@ -190,6 +201,7 @@ libpulsecommon = shared_library('pulsecommon-' + pa_version_major_minor,
   dependencies : [
     libm_dep, thread_dep, dl_dep, shm_dep, iconv_dep, sndfile_dep, dbus_dep,
     x11_dep, libsystemd_dep, glib_dep, gtk_dep, asyncns_dep, libintl_dep,
+    platform_dep, platform_socket_dep,
   ],
   implicit_include_directories : false)