avdevice/decklink: fix MSVC build issues

Purpose: Made minor changes to get the decklink avdevice code to build
using Visual C++.

Notes: Made changes to configure per Hendrik Leppkes's review of first
and second versions of patch.  Also made slight alterations per Marton
Balint's reviews.

Comments:

-- configure: Added if enabled decklink section and setting
   decklink_indev_extralibs and decklink_outdev_extralibs here for
   both mingw and Windows.  Also eliminated the setting of these
   variables in the mingw section earlier in the file.

-- libavdevice/decklink_common.cpp: Switched the order of the include
   of libavformat/internal.h to workaround build issues with Visual
   C++.  See comment in file for more details.

-- libavdevice/decklink_dec.cpp:
a) Rearranged the include of libavformat/internal.h (for reasons as
   described above).
b) Made slight alteration to an argument for call to av_rescale_q() to
   workaround a compiler error with Visual C++.  This appears to only
   be an issue when building C++ files with Visual C++.  See comment
   in code for more details.

-- libavdevice/decklink_enc.cpp: Rearranged the include of
   libavformat/internal.h (for reasons as described above).

Signed-off-by: Aaron Levinson <alevinsn@aracnet.com>
Signed-off-by: Marton Balint <cus@passwd.hu>

1 files changed, 9 insertions, 2 deletions

diff --git a/configure b/configure
index 47c9ee9a35..e2e50e516c 100755
--- a/configure
+++ b/configure
@@ -4853,8 +4853,6 @@ case $target_os in
         else
             target_os=mingw32
         fi
-        decklink_outdev_extralibs="$decklink_outdev_extralibs -lole32 -loleaut32"
-        decklink_indev_extralibs="$decklink_indev_extralibs -lole32 -loleaut32"
         LIBTARGET=i386
         if enabled x86_64; then
             LIBTARGET="i386:x86-64"
@@ -5959,6 +5957,15 @@ if ! disabled sdl2; then
 fi
 enabled sdl2 && enable sdl && add_cflags $sdl2_cflags && add_extralibs $sdl2_extralibs
 
+if enabled decklink; then
+    case $target_os in
+        mingw32*|mingw64*|win32|win64)
+            decklink_outdev_extralibs="$decklink_outdev_extralibs -lole32 -loleaut32"
+            decklink_indev_extralibs="$decklink_indev_extralibs -lole32 -loleaut32"
+            ;;
+    esac
+fi
+
 disabled securetransport || { check_func SecIdentityCreate "-Wl,-framework,CoreFoundation -Wl,-framework,Security" &&
     check_lib securetransport "Security/SecureTransport.h Security/Security.h" "SSLCreateContext SecItemImport" "-Wl,-framework,CoreFoundation -Wl,-framework,Security"; }