SP_Link - add Erlang headers for Win/macOS

These need to be kept inline with headers for the specific version of Erlang the NIF is to be loaded into.

Also, headers for macOS ARM64 chipset are included but are currently not used by CMakeLists.txt - this is in anticipation of future support for Apple Silicon.

Note that the only major difference between headers on different platforms are the size declarations in erl_int_sizes_config.h

Author: samaaron

app/external/sp_link/CMakeLists.txt

@@ -13,18 +13,16 @@ endif(NOT MSVC)
 
 
 # If we need to change something based on this running on CI, we can use if(DEFINED ENV{GITHUB_ACTION})
-if(APPLE)
-    set(ERLANG_INCLUDE_PATH "/usr/local/lib/erlang/usr/include" CACHE PATH "Path to erlang includes")
-elseif(UNIX)
-    set(ERLANG_INCLUDE_PATH "/usr/lib/erlang/usr/include" CACHE PATH "Path to erlang includes")
-elseif(MSVC)
-    if(DEFINED ENV{GITHUB_ACTION})
-        set(ERLANG_INCLUDE_PATH "C:/Program Files/erl10.7/usr/include" CACHE PATH "Path to erlang includes")
-    else()
-        set(ERLANG_INCLUDE_PATH "C:/Program Files/erl-24.0/usr/include" CACHE PATH "Path to erlang includes")
-    endif()
-endif(APPLE)
-
+if(WIN32)
+  set(ERLANG_INCLUDE_PATH ${CMAKE_CURRENT_SOURCE_DIR}/external_libs/erlang_headers/win_x86_64 CACHE STRING "Path to the Erlang header files for 64 bit Windows")
+elseif(${CMAKE_SYSTEM_NAME} MATCHES Darwin) # macOS
+  set(ERLANG_INCLUDE_PATH ${CMAKE_CURRENT_SOURCE_DIR}/external_libs/erlang_headers/mac_x86_64 CACHE STRING "Path to the Erlang header files for 64 bit Intel Macs")
+else()
+  execute_process(
+    COMMAND erl -noshell -eval "io:format(\"~s~n\", [filename:join([lists:concat([code:root_dir(), \"/erts-\", erlang:system_info(version)]), \"include\"])]), init:stop(0)."
+    OUTPUT_VARIABLE FOUND_ERLANG_INCLUDE_PATH OUTPUT_STRIP_TRAILING_WHITESPACE)
+  set(ERLANG_INCLUDE_PATH ${FOUND_ERLANG_INCLUDE_PATH} CACHE STRING "Path to the Erlang header files")
+endif()
 
 # For Link
 include(${PROJECT_SOURCE_DIR}/external_libs/link/AbletonLinkConfig.cmake)

app/external/sp_link/external_libs/erlang_headers/mac_arm64/driver_int.h

@@ -0,0 +1,42 @@
+/*
+ * %CopyrightBegin%
+ * 
+ * Copyright Ericsson AB 1997-2016. All Rights Reserved.
+ * 
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * 
+ * %CopyrightEnd%
+ */
+/*
+ * System dependant driver declarations
+ */
+
+#ifndef __DRIVER_INT_H__
+#define __DRIVER_INT_H__
+
+#ifdef HAVE_SYS_UIO_H
+#include <sys/types.h>
+#include <sys/uio.h>
+
+typedef struct iovec SysIOVec;
+
+#else
+
+typedef struct {
+    char* iov_base;
+    int   iov_len;
+} SysIOVec;
+
+#endif
+
+#endif