Delegate build environment configuration with QUIC_EXTERNAL_TOOLCHAIN (…

…#4625)

Well managed CMake build environments make use of CMAKE_TOOLCHAIN_FILE
to configure build environment such as include/lib search paths,
system libraries, build flags, etc.

This change introduces QUIC_EXTERNAL_TOOLCHAIN build option, which
when enabled stops MSQuic CMake scripts from attempting to
do CMake toolchain job.

QUIC_EXTERNAL_TOOLCHAIN defaults to OFF to preserve original behaviour.

CMakeLists.txt

@@ -90,6 +90,7 @@ option(QUIC_STATIC_LINK_CRT "Statically links the C runtime" ON)
 option(QUIC_STATIC_LINK_PARTIAL_CRT "Statically links the compiler-specific portion of the C runtime" ON)
 option(QUIC_UWP_BUILD "Build for UWP" OFF)
 option(QUIC_GAMECORE_BUILD "Build for GameCore" OFF)
+option(QUIC_EXTERNAL_TOOLCHAIN "Enable if system libs and include paths are configured by CMake toolchain" OFF)
 option(QUIC_PGO "Enables profile guided optimizations" OFF)
 option(QUIC_LINUX_XDP_ENABLED "Enables XDP support" OFF)
 option(QUIC_SOURCE_LINK "Enables source linking on MSVC" ON)
@@ -488,7 +489,11 @@ if(WIN32)
     endif()
 
     if (QUIC_GAMECORE_BUILD)
-        list(APPEND QUIC_COMMON_DEFINES WINAPI_FAMILY=WINAPI_FAMILY_GAMES QUIC_GAMECORE_BUILD QUIC_RESTRICTED_BUILD)
+        list(APPEND QUIC_COMMON_DEFINES QUIC_GAMECORE_BUILD QUIC_RESTRICTED_BUILD)
+    endif()
+
+    if (QUIC_GAMECORE_BUILD AND NOT QUIC_EXTERNAL_TOOLCHAIN)
+        list(APPEND QUIC_COMMON_DEFINES WINAPI_FAMILY=WINAPI_FAMILY_GAMES)
         set(CMAKE_CXX_STANDARD_LIBRARIES "")
         set(CMAKE_CXX_STANDARD_LIBRARIES_INIT "")
         set(CMAKE_C_STANDARD_LIBRARIES "")

src/inc/CMakeLists.txt

@@ -42,10 +42,13 @@ if(WIN32)
     if(QUIC_UWP_BUILD)
         target_link_libraries(base_link INTERFACE OneCore ws2_32 ntdll)
     elseif(QUIC_GAMECORE_BUILD)
-        target_link_options(inc INTERFACE ${Console_LinkOptions})
-        target_compile_options(inc INTERFACE ${Console_ArchOptions})
-        target_link_directories(inc INTERFACE ${Console_EndpointLibRoot})
-        target_link_libraries(base_link INTERFACE xgameplatform ntdll advapi32)
+        target_link_libraries(base_link INTERFACE ntdll advapi32)
+        if(NOT QUIC_EXTERNAL_TOOLCHAIN)
+            target_link_options(inc INTERFACE ${Console_LinkOptions})
+            target_compile_options(inc INTERFACE ${Console_ArchOptions})
+            target_link_directories(inc INTERFACE ${Console_EndpointLibRoot})
+            target_link_libraries(base_link INTERFACE xgameplatform)
+        endif()
     else()
         target_link_libraries(base_link INTERFACE ws2_32 schannel ntdll bcrypt ncrypt crypt32 iphlpapi advapi32)
     endif()

src/platform/CMakeLists.txt

@@ -132,5 +132,8 @@ if(QUIC_TLS STREQUAL "openssl" OR QUIC_TLS STREQUAL "openssl3")
         target_link_libraries(platform PUBLIC "-framework CoreFoundation" "-framework Security")
     endif()
 elseif(QUIC_TLS STREQUAL "schannel")
-    target_link_libraries(platform PUBLIC secur32 onecore)
+    target_link_libraries(platform PUBLIC secur32)
+    if (NOT QUIC_GAMECORE_BUILD)
+        target_link_libraries(platform PUBLIC onecore)
+    endif()
 endif()