Set GIT_HEAD and GIT_DESCRIBE via environmental variables

Set GIT_HEAD and GIT_DESCRIBE before run cmake in case no source repo is
available - booth values must be extracted at clone/pull time

Example:
git log -1 | grep commit | sed 's#commit ##' > debian/git_head; \
git describe > debian/git_describe

export GIT_HEAD=$(shell [ -f debian/git_head ] && cat debian/git_head)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 70b05c9..d9a397f 100644 (file)
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -555,11 +555,11 @@ git_describe(GIT_DESCRIBE --long)
 # If not in a Git repo try to read GIT_HEAD and GIT_DESCRIBE from
 # enviroment
 if (NOT GIT_HEAD OR NOT GIT_DESCRIBE)
-  if (ENV_GIT_HEAD)
-      set(GIT_HEAD ${ENV_GIT_HEAD}) 
+  if (DEFINED ENV{GIT_HEAD})
+      set(GIT_HEAD ${GIT_HEAD}) 
   endif ()
-  if (ENV_GIT_DESCRIBE)
-     set(GIT_DESCRIBE ${ENV_GIT_DESCRIBE})
+  if (DEFINED ENV{GIT_DESCRIBE})
+     set(GIT_DESCRIBE ${GIT_DESCRIBE})
   endif()
 endif()