Provide macro write_basic_config_version_file()

This macro can be used to generate basic version files which can be
installed along a Config.cmake file to provide versioning support.

This (3rd try) is implemented using a macro, which maps
the COMPATIBILITY mode to a filename and configure_file()s the
resulting file.

Alex

1 files changed, 43 insertions, 0 deletions

diff --git a/Modules/BasicConfigVersion-SameMajorVersion.cmake.in b/Modules/BasicConfigVersion-SameMajorVersion.cmake.in
new file mode 100644
index 0000000000..b41ffba403
--- /dev/null
+++ b/Modules/BasicConfigVersion-SameMajorVersion.cmake.in
@@ -0,0 +1,43 @@
+# This is a basic file for the new style find_package() search mode,
+# i.e. Config-mode.
+# It is used by WriteBasicConfigVersionFile.cmake as input file for configure_file()
+# to create a version-file which can be installed along a config.cmake file.
+#
+# The created file sets PACKAGE_VERSION_EXACT if the current version string and
+# the requested version string are exactly the same and it sets
+# PACKAGE_VERSION_COMPATIBLE if the current version is >= requested version,
+# but only if the requested major version is the same as the current one.
+# The variable CVF_VERSION must be set before calling configure_file().
+
+
+set(PACKAGE_VERSION "@CVF_VERSION@")
+
+# check that the installed version has the same 32/64bit-ness as the one which is currently searching:
+if(NOT "${CMAKE_SIZEOF_VOID_P}" STREQUAL "@CMAKE_SIZEOF_VOID_P@")
+   math(EXPR installedBits "@CMAKE_SIZEOF_VOID_P@ * 8")
+   set(PACKAGE_VERSION "${PACKAGE_VERSION} (${installedBits}bit)")
+   set(PACKAGE_VERSION_COMPATIBLE FALSE)
+else()
+
+  if("${PACKAGE_VERSION}" VERSION_LESS "${PACKAGE_FIND_VERSION}" )
+    set(PACKAGE_VERSION_COMPATIBLE FALSE)
+  else()
+
+    if("@CVF_VERSION@" MATCHES "^([0-9]+)\\.")
+      set(CVF_VERSION_MAJOR "${CMAKE_MATCH_1}")
+    else()
+      set(CVF_VERSION_MAJOR "@CVF_VERSION@")
+    endif()
+
+    if("${PACKAGE_FIND_VERSION_MAJOR}" STREQUAL "${CVF_VERSION_MAJOR}")
+      set(PACKAGE_VERSION_COMPATIBLE TRUE)
+    else()
+      set(PACKAGE_VERSION_COMPATIBLE FALSE)
+    endif()
+
+    if( "${PACKAGE_FIND_VERSION}" STREQUAL "${PACKAGE_VERSION}")
+        set(PACKAGE_VERSION_EXACT TRUE)
+    endif()
+  endif()
+
+endif()