Fix build for older CMake versions.

CMake versions newer than ~3.1x automatically determine the subdirectory under CMAKE_INSTALL_PREFIX using the type of the installed target. Older versions need this to be manually computed using the GNUInstallDirs library.

Since we override the CMAKE_INSTALL_PREFIX default, this just controls
the internal layout of the install/ directory generated underneath the
boringssl checkout.

Bug: 488
Change-Id: I97b02006301e463bb0cfd54acb2b27656484cc85
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/52345
Reviewed-by: Adam Langley <agl@google.com>
Reviewed-by: David Benjamin <davidben@google.com>
Commit-Queue: David Benjamin <davidben@google.com>

CMakeLists.txt

diff --git a/CMakeLists.txt b/CMakeLists.txt
index dad27f8..202681d 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -20,6 +20,8 @@
 enable_language(C)
 enable_language(CXX)
 
+include(GNUInstallDirs)
+
 # This is a dummy target which all other targets depend on (manually - see other
 # CMakeLists.txt files). This gives us a hook to add any targets which need to
 # run before all other targets.
@@ -563,7 +565,7 @@
     -DLIBCXX_BUILDING_LIBCXXABI
   )
   target_link_libraries(libcxx libcxxabi)
-  install(TARGETS libcxx EXPORT OpenSSLTargets)
+  install(TARGETS libcxx EXPORT OpenSSLTargets DESTINATION ${CMAKE_INSTALL_LIBDIR})
 endif()
 
 # Add minimal googletest targets. The provided one has many side-effects, and
@@ -665,7 +667,7 @@
     DEPENDS all_tests bssl_shim handshaker fips_specific_tests_if_any
     USES_TERMINAL)
 
-install(DIRECTORY include/ TYPE INCLUDE)
+install(DIRECTORY include/ DESTINATION ${CMAKE_INSTALL_INCLUDEDIR})
 
 install(EXPORT OpenSSLTargets
   FILE OpenSSLTargets.cmake

crypto/CMakeLists.txt

diff --git a/crypto/CMakeLists.txt b/crypto/CMakeLists.txt
index 91ecb3e..6701158 100644
--- a/crypto/CMakeLists.txt
+++ b/crypto/CMakeLists.txt
@@ -441,7 +441,7 @@
  $<BUILD_INTERFACE:${CMAKE_SOURCE_DIR}/include>
  $<INSTALL_INTERFACE:include>
 )
-install(TARGETS crypto EXPORT OpenSSLTargets)
+install(TARGETS crypto EXPORT OpenSSLTargets DESTINATION ${CMAKE_INSTALL_LIBDIR})
 set_property(TARGET crypto PROPERTY EXPORT_NAME Crypto)
 
 if(FIPS_SHARED)

ssl/CMakeLists.txt

diff --git a/ssl/CMakeLists.txt b/ssl/CMakeLists.txt
index ed02bb5..67a72ae 100644
--- a/ssl/CMakeLists.txt
+++ b/ssl/CMakeLists.txt
@@ -45,7 +45,7 @@
   $<BUILD_INTERFACE:${CMAKE_SOURCE_DIR}/include>
   $<INSTALL_INTERFACE:include>
 )
-install(TARGETS ssl EXPORT OpenSSLTargets)
+install(TARGETS ssl EXPORT OpenSSLTargets DESTINATION ${CMAKE_INSTALL_LIBDIR})
 set_property(TARGET ssl PROPERTY EXPORT_NAME SSL)
 
 add_dependencies(ssl global_target)

tool/CMakeLists.txt

diff --git a/tool/CMakeLists.txt b/tool/CMakeLists.txt
index e695f56..f98e96e 100644
--- a/tool/CMakeLists.txt
+++ b/tool/CMakeLists.txt
@@ -21,7 +21,7 @@
   tool.cc
   transport_common.cc
 )
-install(TARGETS bssl)
+install(TARGETS bssl DESTINATION ${CMAKE_INSTALL_BINDIR})
 
 add_dependencies(bssl global_target)