[git] Add git-changelog

git/README

@@ -1,3 +1,28 @@
+# git-changelog #
+
+git-changelog allows one to build a changelog file from the tag
+messages. The tags considered are those whose names follow the format
+vX.Y[.Z[...]] (for example v1.2, v0.0.1, v4.3.2.1, etc.).
+
+One can edit the options into the script to change the message displayed
+at the top of the changelog, and the number of line to separate two tag
+messages.
+
+The changelog is displayed on the standard output, in revese order
+(higher version numbers first), whereas the error output displays the
+included or skipped tag names (i.e. those which do not correspond to the
+pattern).
+
+Note that if there is no tag at all in the repository, no particular
+warning will be displayed.
+
+You can make this script a Git command by putting it in a directory
+within your PATH (e.g. /usr/local/bin) and add an alias in your Git
+configuration:
+
+ git config --global alias.changelog "\!sh -c 'git-changelog'"
+
+
 # git-cherry-move #
 
 git-cherry-move is like git cherry-pick, but it moves the commit

git/git-changelog

@@ -0,0 +1,66 @@
+#!/bin/sh
+#
+# git-changelog, Copyright © 2012 Matteo Cypriani
+#
+# This program is free software. It comes without any warranty, to
+# the extent permitted by applicable law. You can redistribute it
+# and/or modify it under the terms of the Do What The Fuck You Want
+# To Public License, Version 2, as published by Sam Hocevar. See
+# http://sam.zoy.org/wtfpl/COPYING for more details.
+#
+# This script generates a changelog list from the Git tag messages.
+# Only the tags named after the format vX.Y[.Z[...]] are selected.
+# The changelog content is displayed on the standard output, whereas the
+# error output displays the included or skipped tag names.
+
+set -e
+#set -x
+
+### User options
+
+# Message to display at the top of the file (blank to display nothing)
+HEADER="This file is automatically generated from the Git tag messages."
+
+# Number of blank lines between two tag messages
+NEWLINES=2
+
+# Maximal number of lines to display for each tag message
+NBLINES=1000
+
+### End of user options
+
+if [ $# -ne 0 ] ; then
+	echo "Warning! $0 takes no arguments!" >&2
+fi
+
+# Indicates wether or not new lines should be printed
+PRINTNL=0
+
+# Print the header
+if [ "$HEADER" != "" ] ; then
+	echo "$HEADER"
+	PRINTNL=1
+fi
+
+for TAG in $(git tag -l | sort -r) ; do
+	if echo $TAG | egrep '^v[0-9]+(\.[0-9]+)+$' >/dev/null ; then
+		# Display current tag's name
+		echo $TAG >&2
+
+		# Print empty lines if needed
+		if [ $PRINTNL -eq 1 ] ; then
+			i=0
+			while [ $i -lt $NEWLINES ] ; do
+				echo
+				i=`expr $i + 1`
+			done
+		fi
+
+		# Print the tag message
+		git tag -l $TAG -n$NBLINES | sed 's/ \+$//'
+
+		PRINTNL=1
+	else
+		echo "Skipping $TAG" >&2
+	fi
+done