CPack/RPM external symlink handling

Symbolic links that point to external
location no longer cause cmake to fail
with string out of bounds error but
are instead packaged as non relocatable
symlinks and print out a warning message.

4 files changed, 34 insertions, 7 deletions

diff --git a/Help/release/dev/cpack-rpm-external-symlink-handling.rst b/Help/release/dev/cpack-rpm-external-symlink-handling.rst
new file mode 100644
index 0000000..ff74e1d
--- /dev/null
+++ b/Help/release/dev/cpack-rpm-external-symlink-handling.rst
@@ -0,0 +1,5 @@
+cpack-rpm-external-symlink-handling
+-----------------------------------
+
+* The "CPackRPM" module learned how to correctly handle symlinks
+  that are pointing outside generated packages.
diff --git a/Modules/CPackRPM.cmake b/Modules/CPackRPM.cmake
index ae51dc1..713b938 100644
--- a/Modules/CPackRPM.cmake
+++ b/Modules/CPackRPM.cmake
@@ -599,9 +599,10 @@
 # while determining if symlink should be either created or present in a
 # post install script - depending on relocation paths.
 #
-# Currenty there are a few limitations though:
+# Symbolic links that point to locations outside packaging path produce a
+# warning and are treated as non relocatable permanent symbolic links.
 #
-# * Only symbolic links with relative path can be packaged.
+# Currenty there are a few limitations though:
 #
 # * For component based packaging component interdependency is not checked
 #   when processing symbolic links. Symbolic links pointing to content of
@@ -1068,13 +1069,28 @@ function(cpack_rpm_prepare_install_files INSTALL_FILES_LIST WDIR PACKAGE_PREFIXE
           get_filename_component(SYMLINK_POINT_ "${SYMLINK_LOCATION_}/${SYMLINK_POINT_}" ABSOLUTE)
         endif()
 
-        string(SUBSTRING "${SYMLINK_POINT_}" ${WDR_LEN_} -1 SYMLINK_POINT_WD_)
+        # recalculate path length after conversion to canonical form
+        string(LENGTH "${SYMLINK_POINT_}" SYMLINK_POINT_LENGTH_)
 
-        cpack_rpm_symlink_get_relocation_prefixes("${F}" "${PACKAGE_PREFIXES}" "SYMLINK_RELOCATIONS")
-        cpack_rpm_symlink_get_relocation_prefixes("${SYMLINK_POINT_WD_}" "${PACKAGE_PREFIXES}" "POINT_RELOCATIONS")
+        if(SYMLINK_POINT_ MATCHES "${WDIR}/.*")
+          # only symlinks that are pointing inside the packaging structure should be checked for relocation
+          string(SUBSTRING "${SYMLINK_POINT_}" ${WDR_LEN_} -1 SYMLINK_POINT_WD_)
+          cpack_rpm_symlink_get_relocation_prefixes("${F}" "${PACKAGE_PREFIXES}" "SYMLINK_RELOCATIONS")
+          cpack_rpm_symlink_get_relocation_prefixes("${SYMLINK_POINT_WD_}" "${PACKAGE_PREFIXES}" "POINT_RELOCATIONS")
 
-        list(LENGTH SYMLINK_RELOCATIONS SYMLINK_RELOCATIONS_COUNT)
-        list(LENGTH POINT_RELOCATIONS POINT_RELOCATIONS_COUNT)
+          list(LENGTH SYMLINK_RELOCATIONS SYMLINK_RELOCATIONS_COUNT)
+          list(LENGTH POINT_RELOCATIONS POINT_RELOCATIONS_COUNT)
+        else()
+          # location pointed to is ouside WDR so it should be treated as a permanent symlink
+          set(SYMLINK_POINT_WD_ "${SYMLINK_POINT_}")
+
+          unset(SYMLINK_RELOCATIONS)
+          unset(POINT_RELOCATIONS)
+          unset(SYMLINK_RELOCATIONS_COUNT)
+          unset(POINT_RELOCATIONS_COUNT)
+
+          message(AUTHOR_WARNING "CPackRPM:Warning: Symbolic link '${F}' points to location that is outside packaging path! Link will possibly not be relocatable.")
+        endif()
 
         if(SYMLINK_RELOCATIONS_COUNT AND POINT_RELOCATIONS_COUNT)
           # find matching
diff --git a/Tests/CPackComponentsForAll/CMakeLists.txt b/Tests/CPackComponentsForAll/CMakeLists.txt
index 823f6db..05c13a4 100644
--- a/Tests/CPackComponentsForAll/CMakeLists.txt
+++ b/Tests/CPackComponentsForAll/CMakeLists.txt
@@ -92,6 +92,9 @@ if("${CPACK_GENERATOR}" MATCHES "RPM")
   # test symbolic link to location outside package
   execute_process(COMMAND ${CMAKE_COMMAND} -E create_symlink ./outside_package symlink_outside_package)
   install(FILES ${CMAKE_CURRENT_BINARY_DIR}/symlink_outside_package DESTINATION ${CMAKE_INSTALL_LIBDIR}/inside_relocatable_one/depth_two COMPONENT libraries)
+  # test symbolic link to location outside wdr (packaging directory)
+  execute_process(COMMAND ${CMAKE_COMMAND} -E create_symlink /outside_package_wdr symlink_outside_wdr)
+  install(FILES ${CMAKE_CURRENT_BINARY_DIR}/symlink_outside_wdr DESTINATION ${CMAKE_INSTALL_LIBDIR}/inside_relocatable_one/depth_two COMPONENT libraries)
 endif()
 
 # CPack boilerplate for this project
diff --git a/Tests/CPackComponentsForAll/RunCPackVerifyResult.cmake b/Tests/CPackComponentsForAll/RunCPackVerifyResult.cmake
index 0c5cca8..e956f17 100644
--- a/Tests/CPackComponentsForAll/RunCPackVerifyResult.cmake
+++ b/Tests/CPackComponentsForAll/RunCPackVerifyResult.cmake
@@ -188,6 +188,7 @@ if(CPackGen MATCHES "RPM")
 /usr/foo/bar/lib${LIB_SUFFIX}/inside_relocatable_one/depth_two/depth_three
 /usr/foo/bar/lib${LIB_SUFFIX}/inside_relocatable_one/depth_two/depth_three/symlink_parentdir_path
 /usr/foo/bar/lib${LIB_SUFFIX}/inside_relocatable_one/depth_two/symlink_outside_package
+/usr/foo/bar/lib${LIB_SUFFIX}/inside_relocatable_one/depth_two/symlink_outside_wdr
 /usr/foo/bar/lib${LIB_SUFFIX}/inside_relocatable_one/depth_two/symlink_relocatable_subpath
 /usr/foo/bar/lib${LIB_SUFFIX}/inside_relocatable_one/depth_two/symlink_samedir_path
 /usr/foo/bar/lib${LIB_SUFFIX}/inside_relocatable_one/depth_two/symlink_samedir_path_current_dir
@@ -354,6 +355,8 @@ if(CPackGen MATCHES "RPM")
         string(REGEX MATCH "^.*${whitespaces}->${whitespaces}${CPACK_PACKAGING_INSTALL_PREFIX}/non_relocatable/depth_two$" check_symlink "${SYMLINK_POINT_}")
       elseif("${symlink_name}" STREQUAL "symlink_outside_package")
         string(REGEX MATCH "^.*${whitespaces}->${whitespaces}outside_package$" check_symlink "${SYMLINK_POINT_}")
+      elseif("${symlink_name}" STREQUAL "symlink_outside_wdr")
+        string(REGEX MATCH "^.*${whitespaces}->${whitespaces}/outside_package_wdr$" check_symlink "${SYMLINK_POINT_}")
       elseif("${symlink_name}" STREQUAL "symlink_other_relocatable_path"
           OR "${symlink_name}" STREQUAL "symlink_from_non_relocatable_path"
           OR "${symlink_name}" STREQUAL "symlink_relocatable_subpath")