Factorize the version-number parsing and checking code into a separate macro.

Already used by the gpgme version check in kdepim.
FindQt4 has similar code, but since it's a fork of a CMake module I'm not sure if I should modify it

CCMAIL: kde-buildsystem@kde.org

svn path=/trunk/KDE/kdelibs/; revision=537476

2 files changed, 33 insertions, 19 deletions

diff --git a/modules/FindKDE4Internal.cmake b/modules/FindKDE4Internal.cmake
index ad0ccb80..f37cdbb2 100644
--- a/modules/FindKDE4Internal.cmake
+++ b/modules/FindKDE4Internal.cmake
@@ -177,6 +177,8 @@
 # _KDE4_PLATFORM_INCLUDE_DIRS is used only internally
 # _KDE4_PLATFORM_DEFINITIONS is used only internally
 
+INCLUDE (MacroEnsureVersion)
+
 cmake_minimum_required(VERSION 2.4.0 FATAL_ERROR)
 
 set(QT_MIN_VERSION "4.1.1")
@@ -292,6 +294,7 @@ else(EXISTS ${CMAKE_SOURCE_DIR}/kdecore/kglobal.h)
          message ( FATAL_ERROR "ERROR: don't port against this version of kdelibs! Use /branches/work/kdelibs4_snapshot instead!!" )
       endif (_match)
 
+      STRING(REGEX REPLACE "^KDE: " "" KDEVERSION "${KDEVERSION}")
 
       # we need at least this version:
       IF (NOT KDE_MIN_VERSION)
@@ -299,26 +302,9 @@ else(EXISTS ${CMAKE_SOURCE_DIR}/kdecore/kglobal.h)
       ENDIF (NOT KDE_MIN_VERSION)
    
       #message(STATUS "KDE_MIN_VERSION=${KDE_MIN_VERSION}  found ${KDEVERSION}")
-   
-      # now parse the parts of the user given version string into variables
-      STRING(REGEX REPLACE "([0-9]+)\\.[0-9]+\\.[0-9]+" "\\1" req_kde_major_vers "${KDE_MIN_VERSION}")
-      STRING(REGEX REPLACE "[0-9]+\\.([0-9])+\\.[0-9]+" "\\1" req_kde_minor_vers "${KDE_MIN_VERSION}")
-      STRING(REGEX REPLACE "[0-9]+\\.[0-9]+\\.([0-9]+)" "\\1" req_kde_patch_vers "${KDE_MIN_VERSION}")
-   
-      # and now the version string given by kde-config
-      STRING(REGEX REPLACE "KDE: ([0-9]+)\\.[0-9]+\\.[0-9]+.*" "\\1" found_kde_major_vers "${KDEVERSION}")
-      STRING(REGEX REPLACE "KDE: [0-9]+\\.([0-9])+\\.[0-9]+.*" "\\1" found_kde_minor_vers "${KDEVERSION}")
-      STRING(REGEX REPLACE "KDE: [0-9]+\\.[0-9]+\\.([0-9]+).*" "\\1" found_kde_patch_vers "${KDEVERSION}")
-   
-      # compute an overall version number which can be compared at once
-      MATH(EXPR req_vers "${req_kde_major_vers}*10000 + ${req_kde_minor_vers}*100 + ${req_kde_patch_vers}")
-      MATH(EXPR found_vers "${found_kde_major_vers}*10000 + ${found_kde_minor_vers}*100 + ${found_kde_patch_vers}")
-   
-      IF (found_vers LESS req_vers)
-         SET(KDE4_FOUND FALSE)
-         SET(KDE4_INSTALLED_VERSION_TOO_OLD TRUE)
-      ENDIF (found_vers LESS req_vers)
 
+      MACRO_ENSURE_VERSION( ${KDE_MIN_VERSION} ${KDEVERSION} KDE4_INSTALLED_VERSION_TOO_OLD )
+   
    ELSE (KDEVERSION)
       message(FATAL_ERROR "Couldn't parse KDE version string from the kde-config output:\n${kdeconfig_output}")
    ENDIF (KDEVERSION)
diff --git a/modules/MacroEnsureVersion.cmake b/modules/MacroEnsureVersion.cmake
new file mode 100644
index 00000000..c2bcc448
--- /dev/null
+++ b/modules/MacroEnsureVersion.cmake
@@ -0,0 +1,28 @@
+# LGPL-v2, David Faure
+#
+# This macro compares version numbers of the form "x.y.z"
+# MACRO_ENSURE_VERSION( ${FOO_MIN_VERSION} ${FOO_VERSION_FOUND} FOO_TOO_OLD)
+# will set FOO_TOO_OLD to true if FOO_VERSION_FOUND < FOO_MIN_VERSION
+#
+MACRO(MACRO_ENSURE_VERSION requested_version found_version var_too_old)
+
+    message(STATUS "requested_version=${requested_version}  found_version=${found_version}")
+
+    # parse the parts of the version strings
+    STRING(REGEX REPLACE "([0-9]+)\\.[0-9]+\\.[0-9]+" "\\1" req_major_vers "${requested_version}")
+    STRING(REGEX REPLACE "[0-9]+\\.([0-9])+\\.[0-9]+" "\\1" req_minor_vers "${requested_version}")
+    STRING(REGEX REPLACE "[0-9]+\\.[0-9]+\\.([0-9]+)" "\\1" req_patch_vers "${requested_version}")
+   
+    STRING(REGEX REPLACE "([0-9]+)\\.[0-9]+\\.[0-9]+.*" "\\1" found_major_vers "${found_version}")
+    STRING(REGEX REPLACE "[0-9]+\\.([0-9])+\\.[0-9]+.*" "\\1" found_minor_vers "${found_version}")
+    STRING(REGEX REPLACE "[0-9]+\\.[0-9]+\\.([0-9]+).*" "\\1" found_patch_vers "${found_version}")
+   
+    # compute an overall version number which can be compared at once
+    MATH(EXPR req_vers_num "${req_major_vers}*10000 + ${req_minor_vers}*100 + ${req_patch_vers}")
+    MATH(EXPR found_vers_num "${found_major_vers}*10000 + ${found_minor_vers}*100 + ${found_patch_vers}")
+
+    if (found_vers_num LESS req_vers_num)
+        set( ${var_too_old} TRUE )
+    endif (found_vers_num LESS req_vers_num)
+
+ENDMACRO(MACRO_ENSURE_VERSION)