Use HW_NCPUONLINE/_SC_NPROCESSORS_ONLN for FFmpeg, VLC, X264. From Brad.

graphics/ffmpeg/Makefile

@@ -1,9 +1,10 @@
-# $OpenBSD: Makefile,v 1.207 2021/02/23 14:30:04 sthen Exp $
+# $OpenBSD: Makefile,v 1.208 2021/04/03 11:15:46 sthen Exp $
 
 COMMENT=	audio/video converter and streamer
 
 V=		4.3.2
 DISTNAME=	ffmpeg-${V}
+REVISION=	0
 EPOCH=		1
 CATEGORIES=	graphics multimedia
 MASTER_SITES=	https://ffmpeg.org/releases/

graphics/ffmpeg/patches/patch-libavutil_cpu_c

@@ -0,0 +1,18 @@
+$OpenBSD: patch-libavutil_cpu_c,v 1.1 2021/04/03 11:15:46 sthen Exp $
+
+Index: libavutil/cpu.c
+--- libavutil/cpu.c.orig
++++ libavutil/cpu.c
+@@ -283,6 +283,12 @@ int av_cpu_count(void)
+     DWORD_PTR proc_aff, sys_aff;
+     if (GetProcessAffinityMask(GetCurrentProcess(), &proc_aff, &sys_aff))
+         nb_cpus = av_popcount64(proc_aff);
++#elif HAVE_SYSCTL && defined(HW_NCPUONLINE)
++    int mib[2] = { CTL_HW, HW_NCPUONLINE };
++    size_t len = sizeof(nb_cpus);
++
++    if (sysctl(mib, 2, &nb_cpus, &len, NULL, 0) == -1)
++        nb_cpus = 0;
+ #elif HAVE_SYSCTL && defined(HW_NCPU)
+     int mib[2] = { CTL_HW, HW_NCPU };
+     size_t len = sizeof(nb_cpus);

multimedia/x264/Makefile

@@ -1,4 +1,4 @@
-# $OpenBSD: Makefile,v 1.58 2020/11/05 19:42:29 sthen Exp $
+# $OpenBSD: Makefile,v 1.59 2021/04/03 11:15:46 sthen Exp $
 
 COMMENT=	free H.264/MPEG-4 AVC encoder
 
@@ -6,7 +6,7 @@ DISTNAME=	x264-20200705
 GH_ACCOUNT=	mirror
 GH_PROJECT=	x264
 GH_COMMIT=	cde9a93319bea766a92e306d69059c76de970190
-REVISION=	0
+REVISION=	1
 CATEGORIES=	multimedia
 
 SHARED_LIBS=	x264	22.0

multimedia/x264/patches/patch-common_cpu_c

@@ -0,0 +1,31 @@
+$OpenBSD: patch-common_cpu_c,v 1.6 2021/04/03 11:15:46 sthen Exp $
+
+Index: common/cpu.c
+--- common/cpu.c.orig
++++ common/cpu.c
+@@ -433,7 +433,7 @@ int x264_cpu_num_processors( void )
+ #elif SYS_WINDOWS
+     return x264_pthread_num_processors_np();
+ 
+-#elif SYS_CYGWIN || SYS_SunOS
++#elif SYS_CYGWIN || SYS_SunOS || SYS_OPENBSD
+     return sysconf( _SC_NPROCESSORS_ONLN );
+ 
+ #elif SYS_LINUX
+@@ -460,15 +460,10 @@ int x264_cpu_num_processors( void )
+     get_system_info( &info );
+     return info.cpu_count;
+ 
+-#elif SYS_MACOSX || SYS_FREEBSD || SYS_OPENBSD
++#elif SYS_MACOSX || SYS_FREEBSD
+     int ncpu;
+     size_t length = sizeof( ncpu );
+-#if SYS_OPENBSD
+-    int mib[2] = { CTL_HW, HW_NCPU };
+-    if( sysctl(mib, 2, &ncpu, &length, NULL, 0) )
+-#else
+     if( sysctlbyname("hw.ncpu", &ncpu, &length, NULL, 0) )
+-#endif
+     {
+         ncpu = 1;
+     }

x11/vlc/Makefile

@@ -1,4 +1,4 @@
-# $OpenBSD: Makefile,v 1.247 2021/01/23 09:50:09 ajacoutot Exp $
+# $OpenBSD: Makefile,v 1.248 2021/04/03 11:15:46 sthen Exp $
 
 COMMENT-main=	VideoLAN client; multimedia player
 COMMENT-jack=	JACK audio output module for VLC
@@ -7,6 +7,7 @@ V=		3.0.12
 DISTNAME=	vlc-${V}
 PKGNAME-main=	${DISTNAME}
 PKGNAME-jack=	vlc-jack-${V}
+REVISION-main=	0
 CATEGORIES=	x11
 MASTER_SITES=	https://download.videolan.org/pub/videolan/vlc/${V}/
 EXTRACT_SUFX=	.tar.xz

x11/vlc/patches/patch-src_posix_thread_c

@@ -1,7 +1,8 @@
-$OpenBSD: patch-src_posix_thread_c,v 1.4 2019/12/01 22:44:13 ajacoutot Exp $
+$OpenBSD: patch-src_posix_thread_c,v 1.5 2021/04/03 11:15:46 sthen Exp $
 
-Make use of clock_gettime() on OpenBSD. Until we have per-process
-timers and can enable _POSIX_TIMERS in unistd.h.
+- Make use of clock_gettime() on OpenBSD. Until we have per-process
+  timers and can enable _POSIX_TIMERS in unistd.h.
+- Make use of _SC_NPROCESSORS_ONLN.
 
 Index: src/posix/thread.c
 --- src/posix/thread.c.orig
@@ -24,3 +25,12 @@ Index: src/posix/thread.c
      struct timespec ts;
  
      vlc_clock_setup ();
+@@ -712,6 +712,8 @@ unsigned vlc_GetCPUCount(void)
+         count = sysconf (_SC_NPROCESSORS_ONLN);
+     free (cpulist);
+     return count ? count : 1;
++#elif defined(_SC_NPROCESSORS_ONLN)
++    return sysconf(_SC_NPROCESSORS_ONLN);
+ #elif defined(_SC_NPROCESSORS_CONF)
+     return sysconf(_SC_NPROCESSORS_CONF);
+ #else