Use relative paths for CMake package config files

Using relative paths in the 'install' command results in a CMake
target file that does not contain hard-coded/machine dependent absolute
paths to the binary library file. This is useful when building and
installing the library on one machine then copying the installed files
to be consumed on another machine. A common practice when using
distributed builds.

Author: marcomagdy

CMakeLists.txt

@@ -87,9 +87,9 @@ install(FILES "include/aws/logging/logging.h"
 
 install(TARGETS ${PROJECT_NAME}
     EXPORT ${PROJECT_NAME}-targets
-    ARCHIVE DESTINATION ${CMAKE_INSTALL_PREFIX}/lib
-    LIBRARY DESTINATION ${CMAKE_INSTALL_PREFIX}/lib
-    RUNTIME DESTINATION ${CMAKE_INSTALL_PREFIX}/bin)
+    ARCHIVE DESTINATION lib
+    LIBRARY DESTINATION lib
+    RUNTIME DESTINATION bin)
 
 configure_file("${CMAKE_SOURCE_DIR}/cmake/${PROJECT_NAME}-config.cmake"
     "${CMAKE_CURRENT_BINARY_DIR}/${PROJECT_NAME}-config.cmake"
@@ -98,12 +98,12 @@ configure_file("${CMAKE_SOURCE_DIR}/cmake/${PROJECT_NAME}-config.cmake"
 export(EXPORT "${PROJECT_NAME}-targets" NAMESPACE AWS::)
 
 install(EXPORT "${PROJECT_NAME}-targets"
-    DESTINATION "${CMAKE_INSTALL_PREFIX}/lib/${PROJECT_NAME}/cmake/"
+    DESTINATION "lib/${PROJECT_NAME}/cmake/"
     NAMESPACE AWS::)
 
 install(FILES "${CMAKE_CURRENT_BINARY_DIR}/${PROJECT_NAME}-config.cmake"
-    DESTINATION "${CMAKE_INSTALL_PREFIX}/lib/${PROJECT_NAME}/cmake/")
+    DESTINATION "lib/${PROJECT_NAME}/cmake/")
 
 install(PROGRAMS "${CMAKE_SOURCE_DIR}/packaging/packager"
-    DESTINATION "${CMAKE_INSTALL_PREFIX}/lib/${PROJECT_NAME}/cmake/")
+    DESTINATION "lib/${PROJECT_NAME}/cmake/")
 

ci/codebuild/build.sh

@@ -8,4 +8,4 @@ mkdir build
 cd build
 cmake .. -GNinja -DBUILD_SHARED_LIBS=ON -DCMAKE_BUILD_TYPE=Debug -DCMAKE_INSTALL_PREFIX=/install $@
 ninja
-
+ninja install