From 6e248dafd8d4578dc5d94b569eeccda76c7ac70e Mon Sep 17 00:00:00 2001
From: Andreas Schneider <mail@cynapses.org>
Date: Thu, 11 Mar 2010 11:06:15 +0100
Subject: [PATCH] Added version handling in FIND_PACKAGE_HANDLE_STANDARD_ARGS.


Signed-off-by: Andreas Schneider <mail@cynapses.org>
---
 Modules/FindPackageHandleStandardArgs.cmake |   67 ++++++++++++++++++++++++++-
 1 files changed, 65 insertions(+), 2 deletions(-)

diff --git a/Modules/FindPackageHandleStandardArgs.cmake b/Modules/FindPackageHandleStandardArgs.cmake
index e17105c..a5580cc 100644
--- a/Modules/FindPackageHandleStandardArgs.cmake
+++ b/Modules/FindPackageHandleStandardArgs.cmake
@@ -16,9 +16,22 @@
 #    If the second argument is DEFAULT_MSG, the message in the failure case will 
 #    be "Could NOT find LibXml2", if you don't like this message you can specify
 #    your own custom failure message there.
+#
+#    If you set the version before you call FIND_PACKAGE_HANDLE_STANDARD_ARGS
+#    then a version check is performed.
+#    It handles NAME_FIND_VERSION and NAME_VERSION variables in a Module.
+#
+#    Example:
+#    find_package(LibSSH 2.7.0)
+#
+#    # check for the version (read header files, pkg-config ...)
+#    # and set it with:
+#    set(LibXml2 VERSION 2.7.1)
+#    FIND_PACKAGE_HANDLE_STANDARD_ARGS(LibXml2 DEFAULT_MSG LIBXML2_LIBRARIES LIBXML2_INCLUDE_DIR)
 
 #=============================================================================
 # Copyright 2007-2009 Kitware, Inc.
+# Copyrigth 2010 Andreas Schneider
 #
 # Distributed under the OSI-approved BSD License (the "License");
 # see accompanying file Copyright.txt for details.
@@ -38,6 +51,7 @@ FUNCTION(FIND_PACKAGE_HANDLE_STANDARD_ARGS _NAME _FAIL_MSG _VAR1 )
   ELSE("${_FAIL_MSG}" STREQUAL "DEFAULT_MSG")
     SET(_FAIL_MESSAGE "${_FAIL_MSG}")
   ENDIF("${_FAIL_MSG}" STREQUAL "DEFAULT_MSG")
+  set(_AGE "old")
 
   STRING(TOUPPER ${_NAME} _NAME_UPPER)
 
@@ -63,14 +77,63 @@ FUNCTION(FIND_PACKAGE_HANDLE_STANDARD_ARGS _NAME _FAIL_MSG _VAR1 )
     ENDIF(NOT ${_CURRENT_VAR})
   ENDFOREACH(_CURRENT_VAR)
 
+  if (${_NAME_UPPER}_FOUND AND ${_NAME}_VERSION)
+    set(_AGE "old")
+
+    if(${_NAME}_FIND_VERSION_EXACT)
+      if (${_NAME}_FIND_VERSION VERSION_EQUAL ${_NAME}_VERSION)
+        # exact version found
+        set(${_NAME_UPPER}_FOUND TRUE)
+      else (${_NAME}_FIND_VERSION VERSION_EQUAL ${_NAME}_VERSION)
+        # exect version not found
+        set(${_NAME_UPPER}_FOUND FALSE)
+        # check if newer or older
+        if (${_NAME}_FIND_VERSION VERSION_LESS ${_NAME}_VERSION)
+          set(_AGE "new")
+        else (${_NAME}_FIND_VERSION VERSION_LESS ${_NAME}_VERSION)
+          set(_AGE "old")
+        endif (${_NAME}_FIND_VERSION VERSION_LESS ${_NAME}_VERSION)
+      endif (${_NAME}_FIND_VERSION VERSION_EQUAL ${_NAME}_VERSION)
+    else (${_NAME}_FIND_VERSION_EXACT)
+      if (${_NAME}_FIND_VERSION)
+        if (${_NAME}_VERSION VERSION_LESS ${_NAME}_FIND_VERSION)
+          set(${_NAME_UPPER}_FOUND FALSE)
+          set(_AGE "old")
+        else (${_NAME}_VERSION VERSION_LESS ${_NAME}_FIND_VERSION)
+          set(${_NAME_UPPER}_FOUND TRUE)
+       endif (${_NAME}_VERSION VERSION_LESS ${_NAME}_FIND_VERSION)
+      endif (${_NAME}_FIND_VERSION)
+    endif(${_NAME}_FIND_VERSION_EXACT)
+
+    if (NOT ${_NAME_UPPER}_FOUND)
+      if ("${_FAIL_MSG}" STREQUAL "DEFAULT_MSG")
+        if (${_NAME}_FIND_VERSION_EXACT)
+          set(_FAIL_MESSAGE "The installed ${_NAME} version ${${_NAME}_VERSION} is too ${_AGE}, version ${${_NAME}_FIND_VERSION} is required.")
+        else (${_NAME}_FIND_VERSION_EXACT)
+          set(_FAIL_MESSAGE "The installed ${_NAME} version ${${_NAME}_VERSION} is too ${_AGE}, at least version ${${_NAME}_FIND_VERSION} is required.")
+        endif (${_NAME}_FIND_VERSION_EXACT)
+      else ("${_FAIL_MSG}" STREQUAL "DEFAULT_MSG")
+        set(_FAIL_MESSAGE "${_FAIL_MSG}")
+      endif ("${_FAIL_MSG}" STREQUAL "DEFAULT_MSG")
+    endif (NOT ${_NAME_UPPER}_FOUND)
+  endif (${_NAME_UPPER}_FOUND AND ${_NAME}_VERSION)
+
   IF (${_NAME_UPPER}_FOUND)
     FIND_PACKAGE_MESSAGE(${_NAME} "Found ${_NAME}: ${${_VAR1}}" "${DETAILS}")
   ELSE (${_NAME_UPPER}_FOUND)
     IF (${_NAME}_FIND_REQUIRED)
-        MESSAGE(FATAL_ERROR "${_FAIL_MESSAGE} (missing: ${MISSING_VARS})")
+      if (MISSING_VARS)
+        message(FATAL_ERROR "${_FAIL_MESSAGE} (missing: ${MISSING_VARS})")
+      else (MISSING_VARS)
+        message(FATAL_ERROR "${_FAIL_MESSAGE}")
+      endif (MISSING_VARS)
     ELSE (${_NAME}_FIND_REQUIRED)
       IF (NOT ${_NAME}_FIND_QUIETLY)
-        MESSAGE(STATUS "${_FAIL_MESSAGE}  (missing: ${MISSING_VARS})")
+      if (MISSING_VARS)
+        message(STATUS "${_FAIL_MESSAGE}  (missing: ${MISSING_VARS})")
+      else (MISSING_VARS)
+        message(STATUS "${_FAIL_MESSAGE}")
+      endif (MISSING_VARS)
       ENDIF (NOT ${_NAME}_FIND_QUIETLY)
     ENDIF (${_NAME}_FIND_REQUIRED)
   ENDIF (${_NAME_UPPER}_FOUND)
-- 
1.7.0.1

--- /opt/cmake-2.8.1-rc5-Linux-i386/share/cmake-2.8/Modules/FindPackageHandleStandardArgs.cmake	2010-03-11 02:00:34.000000000 +0100
+++ FindPackageHandleStandardArgs.cmake	2010-03-14 16:29:04.000000000 +0100
@@ -2,7 +2,10 @@
 #    This macro is intended to be used in FindXXX.cmake modules files.
 #    It handles the REQUIRED and QUIET argument to FIND_PACKAGE() and
 #    it also sets the <UPPERCASED_NAME>_FOUND variable.
-#    The package is found if all variables listed are TRUE.
+#    The package is considered found if all variables listed are TRUE.
+#    The version-argument of FIND_PACKAGE() is also handled. 
+#    For checking whether the version is ok, this macro compares the 
+#    variable <UPPERCASED_NAME>_VERSION with the specified version.
 #    Example:
 #
 #    FIND_PACKAGE_HANDLE_STANDARD_ARGS(LibXml2 DEFAULT_MSG LIBXML2_LIBRARIES LIBXML2_INCLUDE_DIR)
@@ -63,16 +66,74 @@ FUNCTION(FIND_PACKAGE_HANDLE_STANDARD_AR
     ENDIF(NOT ${_CURRENT_VAR})
   ENDFOREACH(_CURRENT_VAR)
 
+  # version handling:
+  SET(VERSION_MSG "")
+  SET(VERSION_OK TRUE)
+  IF (${_NAME}_FIND_VERSION)
+
+    # if the package was found, check for the version using <NAME>_FIND_VERSION
+    IF (${_NAME_UPPER}_FOUND)
+      SET(VERSION ${${_NAME_UPPER}_VERSION})
+
+      IF(${_NAME}_FIND_VERSION_EXACT)       # exact version required
+        IF (NOT "${${_NAME}_FIND_VERSION}" VERSION_EQUAL "${VERSION}")
+          SET(VERSION_MSG " Found version \"${VERSION}\", but required is exact version \"${${_NAME}_FIND_VERSION}\"")
+          SET(VERSION_OK FALSE)
+        ELSE (NOT "${${_NAME}_FIND_VERSION}" VERSION_EQUAL "${VERSION}")
+          SET(VERSION_MSG " (found exact version \"${VERSION}\")")
+        ENDIF (NOT "${${_NAME}_FIND_VERSION}" VERSION_EQUAL "${VERSION}")
+
+      ELSE(${_NAME}_FIND_VERSION_EXACT)     # minimum version specified:
+        IF ("${${_NAME}_FIND_VERSION}" VERSION_GREATER "${VERSION}")
+          SET(VERSION_MSG " Found version \"${VERSION}\", but required is at least \"${${_NAME}_FIND_VERSION}\"")
+          SET(VERSION_OK FALSE)
+        ELSE ("${${_NAME}_FIND_VERSION}" VERSION_GREATER "${VERSION}")
+          SET(VERSION_MSG " (found version \"${VERSION}\", required is \"${${_NAME}_FIND_VERSION}\")")
+        ENDIF ("${${_NAME}_FIND_VERSION}" VERSION_GREATER "${VERSION}")
+      ENDIF(${_NAME}_FIND_VERSION_EXACT)
+
+    # if the package was not found, but some a version was given, add that to the output:
+    ELSE (${_NAME_UPPER}_FOUND)
+      IF(${_NAME}_FIND_VERSION_EXACT)
+         SET(VERSION_MSG " (Required is exact version \"${${_NAME}_FIND_VERSION}\")")
+      ELSE(${_NAME}_FIND_VERSION_EXACT)
+         SET(VERSION_MSG " (Required is at least version \"${${_NAME}_FIND_VERSION}\")")
+      ENDIF(${_NAME}_FIND_VERSION_EXACT)
+    ENDIF (${_NAME_UPPER}_FOUND)
+  ENDIF (${_NAME}_FIND_VERSION)
+
+  IF(VERSION_OK)
+      SET(DETAILS "${DETAILS}[v${${VERSION}}]")
+  ELSE(VERSION_OK)
+    SET(${_NAME_UPPER}_FOUND FALSE)
+  ENDIF(VERSION_OK)
+
+
+  # print the result:
   IF (${_NAME_UPPER}_FOUND)
-    FIND_PACKAGE_MESSAGE(${_NAME} "Found ${_NAME}: ${${_VAR1}}" "${DETAILS}")
+    FIND_PACKAGE_MESSAGE(${_NAME} "Found ${_NAME}: ${${_VAR1}} ${VERSION_MSG}" "${DETAILS}")
   ELSE (${_NAME_UPPER}_FOUND)
+    IF(NOT VERSION_OK)
+
     IF (${_NAME}_FIND_REQUIRED)
-        MESSAGE(FATAL_ERROR "${_FAIL_MESSAGE} (missing: ${MISSING_VARS})")
+          MESSAGE(FATAL_ERROR "${_FAIL_MESSAGE}: ${VERSION_MSG} (found ${${_VAR1}})")
     ELSE (${_NAME}_FIND_REQUIRED)
       IF (NOT ${_NAME}_FIND_QUIETLY)
-        MESSAGE(STATUS "${_FAIL_MESSAGE}  (missing: ${MISSING_VARS})")
+          MESSAGE(STATUS "${_FAIL_MESSAGE}: ${VERSION_MSG} (found ${${_VAR1}})")
       ENDIF (NOT ${_NAME}_FIND_QUIETLY)
     ENDIF (${_NAME}_FIND_REQUIRED)
+
+    ELSE(NOT VERSION_OK)
+
+      IF (${_NAME}_FIND_REQUIRED)
+          MESSAGE(FATAL_ERROR "${_FAIL_MESSAGE} (missing: ${MISSING_VARS}) ${VERSION_MSG}")
+      ELSE (${_NAME}_FIND_REQUIRED)
+        IF (NOT ${_NAME}_FIND_QUIETLY)
+          MESSAGE(STATUS "${_FAIL_MESSAGE}  (missing: ${MISSING_VARS}) ${VERSION_MSG}")
+        ENDIF (NOT ${_NAME}_FIND_QUIETLY)
+      ENDIF (${_NAME}_FIND_REQUIRED)
+    ENDIF(NOT VERSION_OK)
+
   ENDIF (${_NAME_UPPER}_FOUND)
 
   SET(${_NAME_UPPER}_FOUND ${${_NAME_UPPER}_FOUND} PARENT_SCOPE)

--- /home/alex/src/CMake/CMake/Modules/FindPackageHandleStandardArgs.cmake	2010-02-23 22:10:57.000000000 +0100
+++ FindPackageHandleStandardArgs.cmake	2010-03-15 23:58:33.000000000 +0100
@@ -2,7 +2,12 @@
 #    This macro is intended to be used in FindXXX.cmake modules files.
 #    It handles the REQUIRED and QUIET argument to FIND_PACKAGE() and
 #    it also sets the <UPPERCASED_NAME>_FOUND variable.
-#    The package is found if all variables listed are TRUE.
+#    The package is considered found if all variables listed are TRUE.
+#    The version-argument of FIND_PACKAGE() is also handled. 
+#    For checking whether the version is ok, this macro checks whether any of the 
+#    variables <UPPERCASED_NAME>_VERSION, <OriginalCaseName>_VERSION, 
+#    <UPPERCASED_NAME>_VERSION_STRING and <OriginalCaseName>_VERSION_STRING is set
+#    and compares it with the specified version.
 #    Example:
 #
 #    FIND_PACKAGE_HANDLE_STANDARD_ARGS(LibXml2 DEFAULT_MSG LIBXML2_LIBRARIES LIBXML2_INCLUDE_DIR)
@@ -63,16 +68,89 @@ FUNCTION(FIND_PACKAGE_HANDLE_STANDARD_AR
     ENDIF(NOT ${_CURRENT_VAR})
   ENDFOREACH(_CURRENT_VAR)
 
+  # version handling:
+  SET(VERSION_MSG "")
+  SET(VERSION_OK TRUE)
+  IF (${_NAME}_FIND_VERSION)
+
+    # if the package was found, check for the version using <NAME>_FIND_VERSION
+    IF (${_NAME_UPPER}_FOUND)
+      SET(VERSION ${${_NAME_UPPER}_VERSION}) # consider FOO_VERSION, Foo_VERSION, FOO_VERSION_STRING and Foo_VERSION_STRING
+      IF(NOT VERSION)
+        SET(VERSION ${${_NAME_UPPER}_VERSION_STRING})
+      ENDIF(NOT VERSION)
+      IF(NOT VERSION)
+        SET(VERSION ${${_NAME}_VERSION})
+      ENDIF(NOT VERSION)
+      IF(NOT VERSION)
+        SET(VERSION ${${_NAME}_VERSION_STRING})
+      ENDIF(NOT VERSION)
+
+      IF(VERSION)  #hmm what do we do if the module in question doesn't set FOO_VERSION but something else ?... Ignore it for now
+
+      IF(${_NAME}_FIND_VERSION_EXACT)       # exact version required
+        IF (NOT "${${_NAME}_FIND_VERSION}" VERSION_EQUAL "${VERSION}")
+          SET(VERSION_MSG " Found version \"${VERSION}\", but required is exact version \"${${_NAME}_FIND_VERSION}\"")
+          SET(VERSION_OK FALSE)
+        ELSE (NOT "${${_NAME}_FIND_VERSION}" VERSION_EQUAL "${VERSION}")
+          SET(VERSION_MSG " (found exact version \"${VERSION}\")")
+        ENDIF (NOT "${${_NAME}_FIND_VERSION}" VERSION_EQUAL "${VERSION}")
+
+      ELSE(${_NAME}_FIND_VERSION_EXACT)     # minimum version specified:
+        IF ("${${_NAME}_FIND_VERSION}" VERSION_GREATER "${VERSION}")
+          SET(VERSION_MSG " Found version \"${VERSION}\", but required is at least \"${${_NAME}_FIND_VERSION}\"")
+          SET(VERSION_OK FALSE)
+        ELSE ("${${_NAME}_FIND_VERSION}" VERSION_GREATER "${VERSION}")
+          SET(VERSION_MSG " (found version \"${VERSION}\", required is \"${${_NAME}_FIND_VERSION}\")")
+        ENDIF ("${${_NAME}_FIND_VERSION}" VERSION_GREATER "${VERSION}")
+      ENDIF(${_NAME}_FIND_VERSION_EXACT)
+
+      ELSE(VERSION)
+        SET(VERSION_MSG " (WARNING: Required version is \"${${_NAME}_FIND_VERSION}\", but version of ${_NAME} is unknown)")
+      ENDIF(VERSION)
+
+    # if the package was not found, but some a version was given, add that to the output:
+    ELSE (${_NAME_UPPER}_FOUND)
+      IF(${_NAME}_FIND_VERSION_EXACT)
+         SET(VERSION_MSG " (Required is exact version \"${${_NAME}_FIND_VERSION}\")")
+      ELSE(${_NAME}_FIND_VERSION_EXACT)
+         SET(VERSION_MSG " (Required is at least version \"${${_NAME}_FIND_VERSION}\")")
+      ENDIF(${_NAME}_FIND_VERSION_EXACT)
+    ENDIF (${_NAME_UPPER}_FOUND)
+  ENDIF (${_NAME}_FIND_VERSION)
+
+  IF(VERSION_OK)
+      SET(DETAILS "${DETAILS}[v${${VERSION}}]")
+  ELSE(VERSION_OK)
+    SET(${_NAME_UPPER}_FOUND FALSE)
+  ENDIF(VERSION_OK)
+
+
+  # print the result:
   IF (${_NAME_UPPER}_FOUND)
-    FIND_PACKAGE_MESSAGE(${_NAME} "Found ${_NAME}: ${${_VAR1}}" "${DETAILS}")
+    FIND_PACKAGE_MESSAGE(${_NAME} "Found ${_NAME}: ${${_VAR1}} ${VERSION_MSG}" "${DETAILS}")
   ELSE (${_NAME_UPPER}_FOUND)
+    IF(NOT VERSION_OK)
+
     IF (${_NAME}_FIND_REQUIRED)
-        MESSAGE(FATAL_ERROR "${_FAIL_MESSAGE} (missing: ${MISSING_VARS})")
+          MESSAGE(FATAL_ERROR "${_FAIL_MESSAGE}: ${VERSION_MSG} (found ${${_VAR1}})")
     ELSE (${_NAME}_FIND_REQUIRED)
       IF (NOT ${_NAME}_FIND_QUIETLY)
-        MESSAGE(STATUS "${_FAIL_MESSAGE}  (missing: ${MISSING_VARS})")
+          MESSAGE(STATUS "${_FAIL_MESSAGE}: ${VERSION_MSG} (found ${${_VAR1}})")
       ENDIF (NOT ${_NAME}_FIND_QUIETLY)
     ENDIF (${_NAME}_FIND_REQUIRED)
+
+    ELSE(NOT VERSION_OK)
+
+      IF (${_NAME}_FIND_REQUIRED)
+          MESSAGE(FATAL_ERROR "${_FAIL_MESSAGE} (missing: ${MISSING_VARS}) ${VERSION_MSG}")
+      ELSE (${_NAME}_FIND_REQUIRED)
+        IF (NOT ${_NAME}_FIND_QUIETLY)
+          MESSAGE(STATUS "${_FAIL_MESSAGE}  (missing: ${MISSING_VARS}) ${VERSION_MSG}")
+        ENDIF (NOT ${_NAME}_FIND_QUIETLY)
+      ENDIF (${_NAME}_FIND_REQUIRED)
+    ENDIF(NOT VERSION_OK)
+
   ENDIF (${_NAME_UPPER}_FOUND)
 
   SET(${_NAME_UPPER}_FOUND ${${_NAME_UPPER}_FOUND} PARENT_SCOPE)

diff --git a/Modules/FindPackageHandleStandardArgs.cmake b/Modules/FindPackageHandleStandardArgs.cmake
index e17105c..351a639 100644
--- a/Modules/FindPackageHandleStandardArgs.cmake
+++ b/Modules/FindPackageHandleStandardArgs.cmake
@@ -2,10 +2,19 @@
 #    This macro is intended to be used in FindXXX.cmake modules files.
 #    It handles the REQUIRED and QUIET argument to FIND_PACKAGE() and
 #    it also sets the <UPPERCASED_NAME>_FOUND variable.
-#    The package is found if all variables listed are TRUE.
+#    The package is considered found if all variables listed are TRUE.
+#    The version-argument of FIND_PACKAGE() is also handled. 
+#    For checking whether the version is ok, this macro checks whether any of the 
+#    variables <UPPERCASED_NAME>_VERSION, <OriginalCaseName>_VERSION, 
+#    <UPPERCASED_NAME>_VERSION_STRING and <OriginalCaseName>_VERSION_STRING is set
+#    and compares it with the specified version.
+#    So, before calling FIND_PACKAGE_HANDLE_STANDARD_ARGS(), make sure you have 
+#    <UPPERCASED_NAME>_VERSION set correctly.
 #    Example:
 #
-#    FIND_PACKAGE_HANDLE_STANDARD_ARGS(LibXml2 DEFAULT_MSG LIBXML2_LIBRARIES LIBXML2_INCLUDE_DIR)
+#    SET(LIBXML2_VERSION 2.5.0)   # e.g. from parsing a header file
+#    ...
+#    FIND_PACKAGE_HANDLE_STANDARD_ARGS(LibXml2  DEFAULT_MSG  LIBXML2_LIBRARIES LIBXML2_INCLUDE_DIR)
 #
 #    LibXml2 is considered to be found, if both LIBXML2_LIBRARIES and 
 #    LIBXML2_INCLUDE_DIR are valid. Then also LIBXML2_FOUND is set to TRUE.
@@ -63,16 +72,89 @@ FUNCTION(FIND_PACKAGE_HANDLE_STANDARD_ARGS _NAME _FAIL_MSG _VAR1 )
     ENDIF(NOT ${_CURRENT_VAR})
   ENDFOREACH(_CURRENT_VAR)
 
+  # version handling:
+  SET(VERSION_MSG "")
+  SET(VERSION_OK TRUE)
+  IF (${_NAME}_FIND_VERSION)
+
+    # if the package was found, check for the version using <NAME>_FIND_VERSION
+    IF (${_NAME_UPPER}_FOUND)
+      SET(VERSION ${${_NAME_UPPER}_VERSION}) # consider FOO_VERSION, Foo_VERSION, FOO_VERSION_STRING and Foo_VERSION_STRING
+      IF(NOT VERSION)
+        SET(VERSION ${${_NAME_UPPER}_VERSION_STRING})
+      ENDIF(NOT VERSION)
+      IF(NOT VERSION)
+        SET(VERSION ${${_NAME}_VERSION})
+      ENDIF(NOT VERSION)
+      IF(NOT VERSION)
+        SET(VERSION ${${_NAME}_VERSION_STRING})
+      ENDIF(NOT VERSION)
+
+      IF(VERSION)  #hmm what do we do if the module in question doesn't set FOO_VERSION but something else ?... Ignore it for now
+
+        IF(${_NAME}_FIND_VERSION_EXACT)       # exact version required
+          IF (NOT "${${_NAME}_FIND_VERSION}" VERSION_EQUAL "${VERSION}")
+            SET(VERSION_MSG " Found version \"${VERSION}\", but required is exact version \"${${_NAME}_FIND_VERSION}\"")
+            SET(VERSION_OK FALSE)
+          ELSE (NOT "${${_NAME}_FIND_VERSION}" VERSION_EQUAL "${VERSION}")
+            SET(VERSION_MSG " (found exact version \"${VERSION}\")")
+          ENDIF (NOT "${${_NAME}_FIND_VERSION}" VERSION_EQUAL "${VERSION}")
+
+        ELSE(${_NAME}_FIND_VERSION_EXACT)     # minimum version specified:
+          IF ("${${_NAME}_FIND_VERSION}" VERSION_GREATER "${VERSION}")
+            SET(VERSION_MSG " Found version \"${VERSION}\", but required is at least \"${${_NAME}_FIND_VERSION}\"")
+            SET(VERSION_OK FALSE)
+          ELSE ("${${_NAME}_FIND_VERSION}" VERSION_GREATER "${VERSION}")
+            SET(VERSION_MSG " (found version \"${VERSION}\", required is \"${${_NAME}_FIND_VERSION}\")")
+          ENDIF ("${${_NAME}_FIND_VERSION}" VERSION_GREATER "${VERSION}")
+        ENDIF(${_NAME}_FIND_VERSION_EXACT)
+
+      ELSE(VERSION)
+        SET(VERSION_MSG " (WARNING: Required version is \"${${_NAME}_FIND_VERSION}\", but version of ${_NAME} is unknown)")
+      ENDIF(VERSION)
+
+    # if the package was not found, but some a version was given, add that to the output:
+    ELSE (${_NAME_UPPER}_FOUND)
+      IF(${_NAME}_FIND_VERSION_EXACT)
+         SET(VERSION_MSG " (Required is exact version \"${${_NAME}_FIND_VERSION}\")")
+      ELSE(${_NAME}_FIND_VERSION_EXACT)
+         SET(VERSION_MSG " (Required is at least version \"${${_NAME}_FIND_VERSION}\")")
+      ENDIF(${_NAME}_FIND_VERSION_EXACT)
+    ENDIF (${_NAME_UPPER}_FOUND)
+  ENDIF (${_NAME}_FIND_VERSION)
+
+  IF(VERSION_OK)
+      SET(DETAILS "${DETAILS}[v${${VERSION}}]")
+  ELSE(VERSION_OK)
+    SET(${_NAME_UPPER}_FOUND FALSE)
+  ENDIF(VERSION_OK)
+
+
+  # print the result:
   IF (${_NAME_UPPER}_FOUND)
-    FIND_PACKAGE_MESSAGE(${_NAME} "Found ${_NAME}: ${${_VAR1}}" "${DETAILS}")
+    FIND_PACKAGE_MESSAGE(${_NAME} "Found ${_NAME}: ${${_VAR1}} ${VERSION_MSG}" "${DETAILS}")
   ELSE (${_NAME_UPPER}_FOUND)
-    IF (${_NAME}_FIND_REQUIRED)
-        MESSAGE(FATAL_ERROR "${_FAIL_MESSAGE} (missing: ${MISSING_VARS})")
-    ELSE (${_NAME}_FIND_REQUIRED)
-      IF (NOT ${_NAME}_FIND_QUIETLY)
-        MESSAGE(STATUS "${_FAIL_MESSAGE}  (missing: ${MISSING_VARS})")
-      ENDIF (NOT ${_NAME}_FIND_QUIETLY)
-    ENDIF (${_NAME}_FIND_REQUIRED)
+    IF(NOT VERSION_OK)
+
+      IF (${_NAME}_FIND_REQUIRED)
+          MESSAGE(FATAL_ERROR "${_FAIL_MESSAGE}: ${VERSION_MSG} (found ${${_VAR1}})")
+      ELSE (${_NAME}_FIND_REQUIRED)
+        IF (NOT ${_NAME}_FIND_QUIETLY)
+          MESSAGE(STATUS "${_FAIL_MESSAGE}: ${VERSION_MSG} (found ${${_VAR1}})")
+        ENDIF (NOT ${_NAME}_FIND_QUIETLY)
+      ENDIF (${_NAME}_FIND_REQUIRED)
+
+    ELSE(NOT VERSION_OK)
+
+      IF (${_NAME}_FIND_REQUIRED)
+          MESSAGE(FATAL_ERROR "${_FAIL_MESSAGE} (missing: ${MISSING_VARS}) ${VERSION_MSG}")
+      ELSE (${_NAME}_FIND_REQUIRED)
+        IF (NOT ${_NAME}_FIND_QUIETLY)
+          MESSAGE(STATUS "${_FAIL_MESSAGE}  (missing: ${MISSING_VARS}) ${VERSION_MSG}")
+        ENDIF (NOT ${_NAME}_FIND_QUIETLY)
+      ENDIF (${_NAME}_FIND_REQUIRED)
+    ENDIF(NOT VERSION_OK)
+
   ENDIF (${_NAME_UPPER}_FOUND)
 
   SET(${_NAME_UPPER}_FOUND ${${_NAME_UPPER}_FOUND} PARENT_SCOPE)