Add option for building python bindings (default to ON for back compat) (#177)

* Add option for building python bindings (default to ON for back compat)

* Fix some stragglers for the python target

Author: cmmarslender

.github/workflows/build-c-libraries.yml

@@ -87,7 +87,7 @@ jobs:
       env:
         BUILD_VDF_CLIENT: "N"
       run: |
-        cmake . -DBUILD_CHIAVDFC=ON
+        cmake . -DBUILD_CHIAVDFC=ON -DBUILD_PYTHON=OFF
         cmake --build .
 
     - name: Upload artifacts

src/CMakeLists.txt

@@ -1,5 +1,6 @@
 CMAKE_MINIMUM_REQUIRED(VERSION 3.14 FATAL_ERROR)
 option(BUILD_CHIAVDFC "Build the chiavdfc shared library" OFF)
+option(BUILD_PYTHON "Build the python bindings for chiavdf" ON)
 
 set(CMAKE_CXX_STANDARD 17)
 set(CMAKE_CXX_STANDARD_REQUIRED ON)
@@ -52,28 +53,32 @@ endif()
 # CMake 3.14+
 include(FetchContent)
 
-FetchContent_Declare(
-  pybind11-src
-  GIT_REPOSITORY https://github.com/pybind/pybind11.git
-  GIT_TAG        v2.11.1
-)
-FetchContent_MakeAvailable(pybind11-src)
+if(BUILD_PYTHON)
+  FetchContent_Declare(
+    pybind11-src
+    GIT_REPOSITORY https://github.com/pybind/pybind11.git
+    GIT_TAG        v2.11.1
+  )
+  FetchContent_MakeAvailable(pybind11-src)
 
-pybind11_add_module(chiavdf
-  ${CMAKE_CURRENT_SOURCE_DIR}/python_bindings/fastvdf.cpp
-  ${CMAKE_CURRENT_SOURCE_DIR}/refcode/lzcnt.c
-)
+  pybind11_add_module(chiavdf
+    ${CMAKE_CURRENT_SOURCE_DIR}/python_bindings/fastvdf.cpp
+    ${CMAKE_CURRENT_SOURCE_DIR}/refcode/lzcnt.c
+  )
+
+  target_link_libraries(chiavdf PRIVATE ${GMP_LIBRARIES} ${GMPXX_LIBRARIES})
+  if(UNIX)
+    target_link_libraries(chiavdf PRIVATE -pthread)
+  endif()
+endif()
 
 add_executable(verifier_test
   ${CMAKE_CURRENT_SOURCE_DIR}/verifier_test.cpp
   ${CMAKE_CURRENT_SOURCE_DIR}/refcode/lzcnt.c
 )
-
-target_link_libraries(chiavdf PRIVATE ${GMP_LIBRARIES} ${GMPXX_LIBRARIES})
 target_link_libraries(verifier_test PRIVATE ${GMP_LIBRARIES} ${GMPXX_LIBRARIES})
 
 if(UNIX)
-  target_link_libraries(chiavdf PRIVATE -pthread)
   target_link_libraries(verifier_test PRIVATE -pthread)
 endif()