From 02e8f4272c99f745eb201622c07b0613a8cd22ae Mon Sep 17 00:00:00 2001
From: Daniel Verkamp <daniel@drv.nu>
Date: Sun, 1 Jan 2012 23:54:40 +0000
Subject: [PATCH] win32: detect number of CPUs using affinity

Signed-off-by: Janne Grunau <janne-libav@jannau.net>
---
 configure            |  4 ++--
 libavcodec/pthread.c | 11 ++++++-----
 2 files changed, 8 insertions(+), 7 deletions(-)

diff --git a/configure b/configure
index b7f0acdc0a..481f0eacaf 100755
--- a/configure
+++ b/configure
@@ -1084,9 +1084,9 @@ HAVE_LIST="
     fork
     getaddrinfo
     gethrtime
+    GetProcessAffinityMask
     GetProcessMemoryInfo
     GetProcessTimes
-    GetSystemInfo
     getrusage
     gnu_as
     ibm_asm
@@ -2864,8 +2864,8 @@ check_func  sysctl
 check_func_headers io.h setmode
 check_func_headers lzo/lzo1x.h lzo1x_999_compress
 check_lib2 "windows.h psapi.h" GetProcessMemoryInfo -lpsapi
+check_func_headers windows.h GetProcessAffinityMask
 check_func_headers windows.h GetProcessTimes
-check_func_headers windows.h GetSystemInfo
 check_func_headers windows.h MapViewOfFile
 check_func_headers windows.h VirtualAlloc
 
diff --git a/libavcodec/pthread.c b/libavcodec/pthread.c
index 58c5fcd638..2159a2572d 100644
--- a/libavcodec/pthread.c
+++ b/libavcodec/pthread.c
@@ -35,7 +35,7 @@
 #define _GNU_SOURCE
 #include <sched.h>
 #endif
-#if HAVE_GETSYSTEMINFO
+#if HAVE_GETPROCESSAFFINITYMASK
 #include <windows.h>
 #endif
 #if HAVE_SYSCTL
@@ -169,10 +169,11 @@ static int get_logical_cpus(AVCodecContext *avctx)
     if (!ret) {
         nb_cpus = CPU_COUNT(&cpuset);
     }
-#elif HAVE_GETSYSTEMINFO
-    SYSTEM_INFO sysinfo;
-    GetSystemInfo(&sysinfo);
-    nb_cpus = sysinfo.dwNumberOfProcessors;
+#elif HAVE_GETPROCESSAFFINITYMASK
+    DWORD_PTR proc_aff, sys_aff;
+    ret = GetProcessAffinityMask(GetCurrentProcess(), &proc_aff, &sys_aff);
+    if (ret)
+        nb_cpus = av_popcount64(proc_aff);
 #elif HAVE_SYSCTL && defined(HW_NCPU)
     int mib[2] = { CTL_HW, HW_NCPU };
     size_t len = sizeof(nb_cpus);