Add hidapi project. Don't cache _DEPENDs macros, so depenendcies are only set when externalprojects are added.

external/CMakeLists.txt

@@ -208,6 +208,8 @@ else()
     set(USE_PRECOMPILED_LIBS TRUE)
 endif()
 
+# We don't CACHE for _DEPENDS variable, as the external project is only added when NOT _FOUND
+
 if (NOT LIBUSB_FOUND AND NOT USE_PRECOMPILED_LIBS)
     # Cloning git repo doesn't include configure, so we download the bz2 which does
     ExternalProject_Add(libusb
@@ -218,7 +220,7 @@ if (NOT LIBUSB_FOUND AND NOT USE_PRECOMPILED_LIBS)
             TEST_COMMAND ""
             )
     ExternalProject_Get_Property(libusb install_dir)
-    set(LIBUSB_DEPENDS libusb CACHE INTERNAL "")
+    set(LIBUSB_DEPENDS libusb)
     set(LIBUSB_FOUND ON CACHE INTERNAL "")
     set(LIBUSB_EXTERNAL ON CACHE INTERNAL "")
     set(LIBUSB_INCLUDE_DIR "${install_dir}/include/libusb-1.0" CACHE INTERNAL "")
@@ -232,6 +234,25 @@ if (NOT LIBUSB_FOUND AND NOT USE_PRECOMPILED_LIBS)
     endif ()
 endif (NOT LIBUSB_FOUND AND NOT USE_PRECOMPILED_LIBS)
 
+if (NOT HIDAPI_FOUND AND NOT USE_PRECOMPILED_LIBS)
+    ExternalProject_Add(hidapi
+            GIT_REPOSITORY https://github.com/libusb/hidapi.git
+            PREFIX "${EXTERNAL_BUILD_LIBRARIES}/hidapi"
+            CMAKE_ARGS ${COMMON_CMAKE_ARGS} -DCMAKE_INSTALL_PREFIX=<INSTALL_DIR>
+            TEST_COMMAND ""
+            )
+    ExternalProject_Get_Property(hidapi install_dir)
+    set(HIDAPI_DEPENDS hidapi)
+    set(HIDAPI_FOUND ON CACHE INTERNAL "")
+    set(HIDAPI_EXTERNAL ON CACHE INTERNAL "")
+    set(HIDAPI_ROOT_DIR "${install_dir}" CACHE INTERNAL "")
+    set(HIDAPI_INCLUDE_DIRS "${install_dir}/include" CACHE INTERNAL "")
+    if (APPLE)
+        set(HIDAPI_LIBRARIES "${install_dir}/lib/libhidapi${CMAKE_SHARED_LIBRARY_SUFFIX}" CACHE INTERNAL "")
+        set(MACOS_EXTERNAL_LIBS_FIXUP "${MACOS_EXTERNAL_LIBS_FIXUP};${install_dir}/lib")
+    endif ()
+endif (NOT HIDAPI_FOUND AND NOT USE_PRECOMPILED_LIBS)
+
 if (NOT OPUS_FOUND AND NOT USE_PRECOMPILED_LIBS)
     ExternalProject_Add(opus
             GIT_REPOSITORY https://github.com/xiph/opus
@@ -241,7 +262,7 @@ if (NOT OPUS_FOUND AND NOT USE_PRECOMPILED_LIBS)
             TEST_COMMAND ""
             )
     ExternalProject_Get_Property(opus install_dir)
-    set(OPUS_DEPENDS opus CACHE INTERNAL "")
+    set(OPUS_DEPENDS opus)
     set(OPUS_FOUND ON CACHE INTERNAL "")
     set(OPUS_EXTERNAL ON CACHE INTERNAL "")
     set(OPUS_INCLUDE_DIRS "${install_dir}/include" CACHE INTERNAL "")
@@ -264,7 +285,7 @@ if (NOT ZLIB_FOUND AND NOT USE_PRECOMPILED_LIBS)
             TEST_COMMAND ""
             )
     ExternalProject_Get_Property(zlib install_dir)
-    set(ZLIB_DEPENDS zlib CACHE INTERNAL "")
+    set(ZLIB_DEPENDS zlib)
     set(ZLIB_FOUND ON CACHE INTERNAL "")
     set(ZLIB_EXTERNAL ON CACHE INTERNAL "")
     set(ZLIB_INCLUDE_DIRS "${install_dir}/include" CACHE INTERNAL "")
@@ -286,7 +307,7 @@ if (NOT FAAD_FOUND AND NOT USE_PRECOMPILED_LIBS)
             TEST_COMMAND ""
             )
     ExternalProject_Get_Property(faad source_dir binary_dir install_dir)
-    set(FAAD_DEPENDS faad CACHE INTERNAL "")
+    set(FAAD_DEPENDS faad)
     set(FAAD_FOUND ON CACHE INTERNAL "")
     set(FAAD_EXTERNAL ON CACHE INTERNAL "")
     set(FAAD_INCLUDE_DIR "${install_dir}/include" CACHE INTERNAL "")
@@ -310,7 +331,7 @@ if (NOT FFTW3F_FOUND AND NOT USE_PRECOMPILED_LIBS)
             TEST_COMMAND ""
             )
     ExternalProject_Get_Property(fftw3f source_dir binary_dir)
-    set(FFTW3F_DEPENDS fftw3f CACHE INTERNAL "")
+    set(FFTW3F_DEPENDS fftw3f)
     set(FFTW3F_FOUND ON CACHE INTERNAL "")
     set(FFTW3F_EXTERNAL ON CACHE INTERNAL "")
     set(FFTW3F_INCLUDE_DIRS "${source_dir}/api" "${binary_dir}" CACHE INTERNAL "")
@@ -393,7 +414,7 @@ if (NOT FFMEG_FOUND AND NOT USE_PRECOMPILED_LIBS)
             TEST_COMMAND ""
             )
         ExternalProject_Get_Property(x264 install_dir)
-        set(X264_DEPENDS x264 CACHE INTERNAL "")
+        set(X264_DEPENDS x264)
         set(X264_PKG_CONFIG_DIR "${install_dir}/lib/pkgconfig")
         set(X264_FOUND ON CACHE INTERNAL "")
         set(X264_EXTERNAL ON CACHE INTERNAL "")
@@ -411,7 +432,7 @@ if (NOT FFMEG_FOUND AND NOT USE_PRECOMPILED_LIBS)
             TEST_COMMAND ""
             )
         ExternalProject_Get_Property(x265 install_dir)
-        set(X265_DEPENDS x265 CACHE INTERNAL "")
+        set(X265_DEPENDS x265)
         set(X265_PKG_CONFIG_DIR "${install_dir}/lib/pkgconfig")
         set(X265_FOUND ON CACHE INTERNAL "")
         set(X265_EXTERNAL ON CACHE INTERNAL "")
@@ -428,7 +449,7 @@ if (NOT FFMEG_FOUND AND NOT USE_PRECOMPILED_LIBS)
             TEST_COMMAND ""
             )
         ExternalProject_Get_Property(fdk_aac install_dir)
-        set(FDK_AAC_DEPENDS fdk_aac CACHE INTERNAL "")
+        set(FDK_AAC_DEPENDS fdk_aac)
         set(FDK_AAC_PKG_CONFIG_DIR "${install_dir}/lib/pkgconfig")
         set(FDK_AAC_FOUND ON CACHE INTERNAL "")
         set(FDK_AAC_EXTERNAL ON CACHE INTERNAL "")
@@ -447,7 +468,7 @@ if (NOT FFMEG_FOUND AND NOT USE_PRECOMPILED_LIBS)
             TEST_COMMAND ""
             )
         ExternalProject_Get_Property(mpg123 install_dir)
-        set(MPG123_DEPENDS mpg123 CACHE INTERNAL "")
+        set(MPG123_DEPENDS mpg123)
         set(MPG123_PKG_CONFIG_DIR "${install_dir}/lib/pkgconfig")
         set(MPG123_FOUND ON CACHE INTERNAL "")
         set(MPG123_EXTERNAL ON CACHE INTERNAL "")
@@ -467,7 +488,7 @@ if (NOT FFMEG_FOUND AND NOT USE_PRECOMPILED_LIBS)
             TEST_COMMAND ""
             )
         ExternalProject_Get_Property(lame install_dir)
-        set(LAME_DEPENDS lame CACHE INTERNAL "")
+        set(LAME_DEPENDS lame)
         # ffmpeg doesn't try to use pkg-config for lame, as it doesn't include a .pc file
         #set(LAME_PKG_CONFIG_DIR "${install_dir}/lib/pkgconfig")
         set(LAME_EXTRA_CFLAGS "-I${install_dir}/include")
@@ -491,7 +512,7 @@ if (NOT FFMEG_FOUND AND NOT USE_PRECOMPILED_LIBS)
             TEST_COMMAND ""
             )
     ExternalProject_Get_Property(ffmpeg install_dir)
-    set(FFMPEG_DEPENDS ffmpeg CACHE INTERNAL "")
+    set(FFMPEG_DEPENDS ffmpeg)
     set(FFMPEG_INSTALL_DIR "${install_dir}")
     set(FFMPEG_FOUND ON CACHE INTERNAL "")
     set(FFMPEG_EXTERNAL ON CACHE INTERNAL "")
@@ -523,7 +544,7 @@ if (NOT OpenCV_FOUND AND NOT USE_PRECOMPILED_LIBS)
             TEST_COMMAND ""
             )
     ExternalProject_Get_Property(opencv source_dir binary_dir)
-    set(OpenCV_DEPENDS opencv CACHE INTERNAL "")
+    set(OpenCV_DEPENDS opencv)
     set(OpenCV_FOUND ON CACHE INTERNAL "")
     set(OpenCV_EXTERNAL ON CACHE INTERNAL "")
     set(OpenCV_INCLUDE_DIRS
@@ -578,7 +599,7 @@ if ((NOT CODEC2_FOUND OR CODEC2_EXTERNAL) AND NOT USE_PRECOMPILED_LIBS)
             TEST_COMMAND ""
             )
     ExternalProject_Get_Property(codec2 source_dir binary_dir)
-    set(CODEC2_DEPENDS codec2 CACHE INTERNAL "")
+    set(CODEC2_DEPENDS codec2)
     set(CODEC2_FOUND ON CACHE INTERNAL "")
     set(CODEC2_EXTERNAL ON CACHE INTERNAL "")
     set(CODEC2_INCLUDE_DIR "${source_dir}/src" "${binary_dir}" CACHE INTERNAL "")
@@ -619,7 +640,7 @@ if (NOT CM256CC_FOUND OR CM256CC_EXTERNAL)
             TEST_COMMAND ""
             )
     ExternalProject_Get_Property(cm256cc source_dir binary_dir)
-    set(CM256CC_DEPENDS cm256cc CACHE INTERNAL "")
+    set(CM256CC_DEPENDS cm256cc)
     set(CM256CC_FOUND ON CACHE INTERNAL "")
     set(CM256CC_EXTERNAL ON CACHE INTERNAL "")
     # we need cm256cc/library.h