[gnome-sound-theme] Autogenerate ChangeLog file on make dist (untested)

[Luca Ferretti <lferrett src gnome org>]

commit 3e1c6997d59c929955fc74ef17d0f0bbf594bef0
Author: Luca Ferretti <elle uca libero it>
Date:   Thu Apr 23 10:16:27 2009 +0200

    Autogenerate ChangeLog file on make dist (untested)
---
 ChangeLog   |    7 ++-----
 Makefile.am |   13 +++++++++++++
 2 files changed, 15 insertions(+), 5 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 033e2eb..826fc8c 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,8 +1,5 @@
 2008-08-09  Luca Ferretti  <elle uca libero it>
 
-	* index.theme.in: Fixed stupid typos to make theme work.
-
-2008-08-09  Luca Ferretti  <elle uca libero it>
-
-	* *:intial version.
+	* *: The ChangeLog is auto-generated when releasing. If you
+        are seeing this, use 'git log' for a detailed list of changes.
 
diff --git a/Makefile.am b/Makefile.am
index 917ab67..3fc33c1 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -30,3 +30,16 @@ MAINTAINERCLEANFILES =			\
 	missing				\
 	mkinstalldirs
 
+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 --stat ) > 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