Create macOS configuration variables for triplets (#4477)

* Create macOS configuration variables for triplets

* Add new macOS configuration variables to documentation

* [vcpkg-configure-cmake] Fix typo

docs/users/triplets.md

@@ -69,6 +69,17 @@ This option also has forms for configuration-specific and C flags:
 - `VCPKG_C_FLAGS_DEBUG`
 - `VCPKG_C_FLAGS_RELEASE`
 
+## macOS Variables
+
+### VCPKG_INSTALL_NAME_DIR
+Sets the install name used when building macOS dynamic libraries. Default value is `@rpath`. See the CMake documentation for [CMAKE_INSTALL_NAME_DIR](https://cmake.org/cmake/help/latest/variable/CMAKE_INSTALL_NAME_DIR.html) for more information.
+
+### VCPKG_OSX_DEPLOYMENT_TARGET
+Sets the minimum macOS version for compiled binaries. This also changes what versions of the macOS platform SDK that CMake will search for. See the CMake documentation for [CMAKE_OSX_DEPLOYMENT_TARGET](https://cmake.org/cmake/help/latest/variable/CMAKE_OSX_DEPLOYMENT_TARGET.html) for more information.
+
+### VCPKG_OSX_SYSROOT
+Set the name or path of the macOS platform SDK that will be used by CMake. See the CMake documentation for [CMAKE_OSX_SYSROOT](https://cmake.org/cmake/help/latest/variable/CMAKE_OSX_SYSROOT.html) for more information.
+
 ## Per-port customization
 The CMake Macro `PORT` will be set when interpreting the triplet file and can be used to change settings (such as `VCPKG_LIBRARY_LINKAGE`) on a per-port basis.
 

scripts/cmake/vcpkg_configure_cmake.cmake

@@ -201,6 +201,17 @@ function(vcpkg_configure_cmake)
         )
     endif()
 
+    # Sets configuration variables for macOS builds
+    if(DEFINED VCPKG_INSTALL_NAME_DIR)
+        list(APPEND _csc_OPTIONS "-DCMAKE_INSTALL_NAME_DIR=${VCPKG_INSTALL_NAME_DIR}")
+    endif()
+    if(DEFINED VCPKG_OSX_DEPLOYMENT_TARGET)
+        list(APPEND _csc_OPTIONS "-DCMAKE_OSX_DEPLOYMENT_TARGET=${VCPKG_OSX_DEPLOYMENT_TARGET}")
+    endif()
+    if(DEFINED VCPKG_OSX_SYSROOT)
+        list(APPEND _csc_OPTIONS "-DCMAKE_OSX_SYSROOT=${VCPKG_OSX_SYSROOT}")
+    endif()
+
     set(rel_command
         ${CMAKE_COMMAND} ${_csc_SOURCE_PATH} "${_csc_OPTIONS}" "${_csc_OPTIONS_RELEASE}"
         -G ${GENERATOR}

scripts/toolchains/osx.cmake

@@ -9,6 +9,8 @@ else()
 endif()
 set(CMAKE_SYSTEM_NAME Darwin CACHE STRING "")
 
+set(CMAKE_MACOSX_RPATH ON CACHE BOOL "")
+
 get_property( _CMAKE_IN_TRY_COMPILE GLOBAL PROPERTY IN_TRY_COMPILE )
 if(NOT _CMAKE_IN_TRY_COMPILE)
     set(CMAKE_CXX_FLAGS "${VCPKG_CXX_FLAGS} -fPIC" CACHE STRING "")