Initial commit

.gitmodules

@@ -13,3 +13,6 @@
 [submodule "submodules/nghttp2"]
 	path = submodules/nghttp2
 	url = https://github.com/nghttp2/nghttp2
+[submodule "submodules/c-ares"]
+	path = submodules/c-ares
+	url = https://github.com/c-ares/c-ares

CMakeLists.txt

@@ -11,6 +11,7 @@ project(
 option(KAI_ENABLE_LTO "Turn on compiler Link Time Optimizations" OFF)
 option(KAI_ENABLE_UNICODE "Enable unicode support for Windows builds" ON)
 option(KAI_ENABLE_HTTP2 "Enable HTTP/2 support in cURL" ON)
+option(KAI_ENABLE_ASYNC_RESOLVER "Enable async DNS resolver support in cURL" ON)
 
 set(
 	MODIFY_OUTPUT_DIRECTORY
@@ -68,6 +69,11 @@ if (KAI_ENABLE_HTTP2)
 	set(USE_NGHTTP2 ON)
 endif()
 
+if (KAI_ENABLE_ASYNC_RESOLVER)
+	set(ENABLE_ARES ON)
+	set(ENABLE_THREADED_RESOLVER OFF)
+endif()
+
 if (WIN32 AND KAI_ENABLE_UNICODE)
 	set(ENABLE_UNICODE ON)
 endif()
@@ -107,6 +113,20 @@ if (KAI_ENABLE_HTTP2)
 	list(APPEND MODIFY_OUTPUT_DIRECTORY nghttp2)
 endif()
 
+if (KAI_ENABLE_ASYNC_RESOLVER)
+	set(
+		CARES_INCLUDE_DIR
+		"${CMAKE_CURRENT_SOURCE_DIR}/submodules/c-ares/include"
+		"${CMAKE_CURRENT_BINARY_DIR}/submodules/c-ares"
+	)
+
+	set(CARES_LIBRARY "${CMAKE_CURRENT_BINARY_DIR}/${CMAKE_SHARED_LIBRARY_PREFIX}cares${CMAKE_SHARED_LIBRARY_SUFFIX}")
+
+	list(APPEND CURL_LIBRARY_DEPENDENCIES c-ares)
+	list(APPEND INTERNAL_LIBRARY_TARGETS c-ares)
+	list(APPEND MODIFY_OUTPUT_DIRECTORY c-ares)
+endif()
+
 include_directories(
 	"${CMAKE_SOURCE_DIR}/src"
 	"${CMAKE_SOURCE_DIR}/submodules/bearssl/src"
@@ -446,6 +466,10 @@ if (KAI_ENABLE_HTTP2)
 	endif()
 endif()
 
+if (KAI_ENABLE_ASYNC_RESOLVER)
+	add_subdirectory(submodules/c-ares EXCLUDE_FROM_ALL)
+endif()
+
 foreach(target ${CURL_LIBRARY_DEPENDENCIES})
 	add_custom_command(
 		OUTPUT ${target}