[libchamplain] Generate changelog the same way as recommended by live.gnome.org

[Jiří Techet <jiritechet src gnome org>]

commit 8fa46ff85b2ae61ff6d5286c9a198aaec6cfd714
Author: JiÅ?í Techet <techet gmail com>
Date:   Mon May 17 23:38:34 2010 +0200

    Generate changelog the same way as recommended by live.gnome.org
    
    Signed-off-by: JiÅ?í Techet <techet gmail com>

 Makefile.am |   16 ++++++++++++++--
 1 files changed, 14 insertions(+), 2 deletions(-)
---
diff --git a/Makefile.am b/Makefile.am
index c1ed57b..072645a 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -48,5 +48,17 @@ all: $(other_pcfiles)
 # Have the demos build at the end as they depend on optional parts
 SUBDIRS += docs demos bindings
 
-ChangeLog: Makefile.am
-	git log --pretty=short > ChangeLog
+dist-hook:
+	@if test -d "$(srcdir)/.git"; \
+	then \
+		echo Creating ChangeLog && \
+		( cd "$(top_srcdir)" && \
+		  echo '# Generated by Makefile. Do not edit.'; echo; \
+		  $(top_srcdir)/missing --run git log --pretty=medium ) > ChangeLog.tmp \
+		&& mv -f ChangeLog.tmp $(top_distdir)/ChangeLog \
+		|| ( rm -f ChangeLog.tmp ; \
+		     echo Failed to generate ChangeLog >&2 ); \
+	else \
+		echo A git clone is required to generate a ChangeLog >&2; \
+	fi
+