1 files changed, 73 insertions, 0 deletions
diff --git a/modules/check_installed_exports_file.cmake b/modules/check_installed_exports_file.cmake
new file mode 100644
index 00000000..d1d0c718
--- /dev/null
+++ b/modules/check_installed_exports_file.cmake
@@ -0,0 +1,73 @@
+
+# This file is executed via install(SCRIPT).
+# This means it is include()d into the cmake_install.cmake file
+# Due to this the following variables already have the correct value:
+# CMAKE_INSTALL_PREFIX
+# CMAKE_CURRENT_BINARY_DIR
+#
+# Additionally the following two variables have to be set:
+# EXPORT_INSTALL_DIR - set it to the install destination
+# EXPORT_FILES  - the filenames of the exports file
+#
+# Alex
+
+
+# put all the code into a function so all variables used here are local
+# which makes sure including this file multiple times in a cmake_install.cmake works
+function(CHECK_INSTALLED_EXPORTS_FILE _filename)
+
+   # get the absolute install directory, consider absolute and relative paths and also DESTDIR
+   if(IS_ABSOLUTE "${EXPORT_INSTALL_DIR}")
+      set(installDir "$ENV{DESTDIR}${EXPORT_INSTALL_DIR}")
+   else(IS_ABSOLUTE "${EXPORT_INSTALL_DIR}")
+      set(installDir "$ENV{DESTDIR}${CMAKE_INSTALL_PREFIX}/${EXPORT_INSTALL_DIR}")
+   endif(IS_ABSOLUTE "${EXPORT_INSTALL_DIR}")
+
+   set(installedExportsFile "${installDir}/${_filename}")
+
+   #message(STATUS "************ bin dir: ${CMAKE_CURRENT_BINARY_DIR}")
+   #message(STATUS "************ prefix: ${CMAKE_INSTALL_PREFIX}")
+   #message(STATUS "************ exportsfile: ${installedExportsFile}")
+
+   # if the file already exists at the install location, and if we can
+   # find the exports file in the build dir, read both, and if their contents differ,
+   # remove all configuration-specific exports files from the install dir, since
+   # they may create conflicts if the new targets have been added/targets have been 
+   # removed/ targets have been renamed/ the namespace for the exported targets has changed
+   if(EXISTS "${installedExportsFile}")
+      if (${EXPORT_INSTALL_DIR} MATCHES "^(/)(.+)$")
+         set(binaryDirExportFileDir "_${CMAKE_MATCH_2}")
+         set(binaryDirExportsFile "${CMAKE_CURRENT_BINARY_DIR}/CMakeFiles/Export/${binaryDirExportFileDir}/${_filename}")
+      else (${EXPORT_INSTALL_DIR} MATCHES "^(/)(.+)$")
+         set(binaryDirExportsFile "${CMAKE_CURRENT_BINARY_DIR}/CMakeFiles/Export/${EXPORT_INSTALL_DIR}/${_filename}")
+      endif (${EXPORT_INSTALL_DIR} MATCHES "^(/)(.+)$")
+
+   #   message(STATUS "************* binaryDirExportsFile: ${binaryDirExportsFile}")
+
+      if(EXISTS "${binaryDirExportsFile}") 
+         file(READ "${installedExportsFile}" installedExportsFileContents)
+         file(READ "${binaryDirExportsFile}" binaryDirExportsFileContents)
+
+         if(NOT "${installedExportsFileContents}" STREQUAL "${binaryDirExportsFileContents}")
+
+            if("${_filename}" MATCHES "^(.+)(\\.cmake)$")
+               message(STATUS "XXX Installed and new ${_filename} differ, removing installed ${CMAKE_MATCH_1}-*.cmake files")
+               file(GLOB exportFiles "${installDir}/${CMAKE_MATCH_1}-*.cmake")
+#               message(STATUS "XXX files: ${exportFiles}")
+               file(REMOVE ${exportFiles})
+            endif("${_filename}" MATCHES "^(.+)(\\.cmake)$")
+         else(NOT "${installedExportsFileContents}" STREQUAL "${binaryDirExportsFileContents}")
+#            message(STATUS "XXX FILES ${_filename} are the same")
+         endif(NOT "${installedExportsFileContents}" STREQUAL "${binaryDirExportsFileContents}")
+
+      endif(EXISTS "${binaryDirExportsFile}") 
+
+   endif(EXISTS "${installedExportsFile}")
+
+endfunction(CHECK_INSTALLED_EXPORTS_FILE)
+
+# call the function for each exports file
+foreach(_currentExportsFile ${EXPORT_FILES})
+   check_installed_exports_file("${_currentExportsFile}")
+endforeach(_currentExportsFile ${EXPORT_FILES})
+