Vendor the PortAudio dependency as a submodule with ExternalProject.

This commits adds a submodule pointing to the portaudio
pa_stable_v190600_20161030 (same as latest FlexASIO release bundle)
and extends the FlexASIO CMake superbuild to build the PortAudio
dependency. This ensures that FlexASIO is built against a
well-defined PortAudio library, and will make it easy to migrate
to a different PortAudio revision in the future. It also gets rid of
the dependency on vcpkg.

Closes #37.

.gitmodules

@@ -1,3 +1,6 @@
 [submodule "src/tinytoml"]
 	path = src/tinytoml
 	url = https://github.com/mayah/tinytoml.git
+[submodule "src/portaudio"]
+	path = src/portaudio
+	url = https://git.assembla.com/portaudio.git

src/CMakeLists.txt

@@ -19,14 +19,36 @@ ExternalProject_Add(
     EXCLUDE_FROM_ALL
 )
 
+find_path(DXSDK_INCLUDE_DIR dsound.h)
+find_library(DXSDK_DSOUND_LIBRARY dsound.lib)
+ExternalProject_Add(
+	portaudio
+	SOURCE_DIR "${CMAKE_CURRENT_LIST_DIR}/portaudio"
+	INSTALL_DIR "${INTERNAL_INSTALL_PREFIX}"
+    BUILD_ALWAYS TRUE USES_TERMINAL_BUILD TRUE
+	# In the version we're currently using, PortAudio doesn't have an install target.
+	CMAKE_ARGS ${CMAKE_ARGS}
+		"-DCMAKE_LIBRARY_OUTPUT_DIRECTORY=${INTERNAL_INSTALL_PREFIX}/bin"
+		"-DCMAKE_RUNTIME_OUTPUT_DIRECTORY=${INTERNAL_INSTALL_PREFIX}/bin"
+		"-DCMAKE_ARCHIVE_OUTPUT_DIRECTORY=${INTERNAL_INSTALL_PREFIX}/lib"
+		-DPA_ENABLE_DEBUG_OUTPUT=ON
+		"-DCMAKE_C_FLAGS=-DPA_GIT_REVISION=396fe4b6699ae929d3a685b3ef8a7e97396139a4-FlexASIO"  # TODO: stop hardcoding this
+		# Work around https://lists.columbia.edu/pipermail/portaudio/2017-January/001001.html
+		-DMSVS=ON
+		# Work around lack of https://app.assembla.com/spaces/portaudio/git/commits/0baa1e2e31f37bac2883ea59e50b76037271426d
+		"-DDXSDK_ROOT_DIR=${DXSDK_INCLUDE_DIR}/.." "-DDXSDK_INCLUDE_DIR=${DXSDK_INCLUDE_DIR}" "-DDXSDK_DSOUND_LIBRARY=${DXSDK_DSOUND_LIBRARY}"
+		INSTALL_COMMAND "${CMAKE_COMMAND}" -E copy_directory "${CMAKE_CURRENT_LIST_DIR}/portaudio/include" "${INTERNAL_INSTALL_PREFIX}/include"
+	EXCLUDE_FROM_ALL
+)
+
 ExternalProject_Add(
     FlexASIO
     SOURCE_DIR "${CMAKE_CURRENT_LIST_DIR}/flexasio"
     USES_TERMINAL_CONFIGURE TRUE
     BUILD_ALWAYS TRUE USES_TERMINAL_BUILD TRUE
     INSTALL_DIR "${INTERNAL_INSTALL_PREFIX}"
     CMAKE_ARGS ${CMAKE_ARGS}
-    DEPENDS tinytoml
+    DEPENDS tinytoml portaudio
 )
 
 install(DIRECTORY "${INTERNAL_INSTALL_PREFIX}/" DESTINATION "${CMAKE_INSTALL_PREFIX}")

src/README.md

@@ -5,38 +5,29 @@
 FlexASIO is designed to be built using CMake within the Microsoft Visual C++
 2017 toolchain native CMake support.
 
-For the build to work you will need to provide the [PortAudio][] dependency. The
-easiest way is to use [vcpkg][]:
+FlexASIO uses a CMake "superbuild" system (in `/src`) to automatically build the
+[tinytoml][] and [PortAudio][] dependencies before building FlexASIO itself.
+These dependencies are pulled in as git submodules; make sure to run
+`git submodule update --init`.
 
-```
-vcpkg install portaudio:x64-windows portaudio:x86-windows
-```
-
-Note that vcpkg needs to be integrated with CMake for the build to work. You
-can use the method described in the vcpkg documentation, or you might find it
-easier to simply set the `VCPKG_DIR` environment variable to your vcpkg
-directory.
-
-The FlexASIO CMake build system will download the [ASIO SDK][] for you
-automatically at configure time.
+If you want to handle the dependencies yourself, you can build FlexASIO in
+isolation from `/src/flexasio`.
 
-The [tinytoml][] dependency is pulled in as a git submodule. Make sure to
-run `git submodule update --init`.
+In any case, the FlexASIO CMake build system will download the [ASIO SDK][] for
+you automatically at configure time.
 
 ## Packaging
 
-The following command will do a clean build and generate a FlexASIO installer
-package for you:
+The following command will do a clean superbuild and generate a FlexASIO
+installer package for you:
 
 ```
 cmake -P installer.cmake
 ```
 
-Note that for this command to work, you need to have [Inno Setup][] installed,
-and the `VCPKG_DIR` environment variable must be set.
+Note that for this command to work, you need to have [Inno Setup][] installed.
 
 [ASIO SDK]: http://www.steinberg.net/en/company/developer.html
 [Inno Setup]: http://www.jrsoftware.org/isdl.php
 [PortAudio]: http://www.portaudio.com/
 [tinytoml]: https://github.com/mayah/tinytoml
-[vcpkg]: https://github.com/Microsoft/vcpkg

src/flexasio/CMakeLists.txt

@@ -1,10 +1,6 @@
 cmake_minimum_required(VERSION 3.11)
 project(FlexASIO DESCRIPTION "FlexASIO Universal ASIO Driver")
 
-if(DEFINED ENV{VCPKG_DIR})
-	include("$ENV{VCPKG_DIR}/scripts/buildsystems/vcpkg.cmake")
-endif()
-
 if(CMAKE_SIZEOF_VOID_P EQUAL 4)
 	set(FLEXASIO_PLATFORM x86)
 elseif(CMAKE_SIZEOF_VOID_P EQUAL 8)

src/flexasio/CMakeModules/Findportaudio.cmake

@@ -1,5 +1,5 @@
 find_path(portaudio_INCLUDE_DIR	NAMES portaudio.h)
-find_library(portaudio_LIBRARY NAMES portaudio)
+find_library(portaudio_LIBRARY NAMES "portaudio_${FLEXASIO_PLATFORM}")
 mark_as_advanced(portaudio_INCLUDE_DIR portaudio_LIBRARY)
 
 include(FindPackageHandleStandardArgs)
@@ -11,5 +11,4 @@ if(portaudio_FOUND AND NOT TARGET portaudio::portaudio)
 		IMPORTED_LOCATION "${portaudio_LIBRARY}"
 		INTERFACE_INCLUDE_DIRECTORIES "${portaudio_INCLUDE_DIR}"
 	)
-	install(FILES "${portaudio_LIBRARY}/../../bin/portaudio_${FLEXASIO_PLATFORM}.dll" DESTINATION bin)
 endif()