Create a git repository on top of a Subversion working copy.

git-ontop.sh

#!/bin/sh

# Create a git repository on top of a Subversion working copy (all files added,
# including files in different SVN repositories checked out via svn:externals
# property). Additionally .gitginore files are added according to svn:ignore
# properties.
# Used for local git workflow ability with official SVN repo. Alternative to
# 'git-svn' with less possibilities, but faster and without compatibility
# concerns. The git repo is meant to be a throw-away repository.
#
# This is a Q&D script, using git porcelain rather than plumbing and other
# quirks.
#
# Limitations/TODO:
# - Cleanup is not yet automated.
# - Maybe use Subversion API and libgit2?
#
# Usage:
# - Put this script into a directory included in the PATH environment variable
#   so that 'git' can find it and rename it to 'git-ontop'.
# - Invoke 'git ontop' without parameters (parameters/commands will be added in
#   the future).

svn info >/dev/null || exit 1

if [ $(LANG=C svn status | grep -v "^Performing\|^?\|^X\|^$\|^.$" | wc -l) -gt 0 ]
then
	echo "error: Subversion working copy dirty"
	exit 1
fi

git init

# we do not care about line endings, just keep them as is to avoid hassle
git config --local core.autocrlf false

# creation of ignorefiles
echo -e "# generated by git-ontop\n/.gitignore" > .gitignore

# svn propget output looks like this (including the leading spaces between blocks):
# Properties on 'Source':
#   svn:ignore
#     Main.o
#     Module.o
#     
LANG=C svn propget -Rv svn:ignore | awk ' \
	/^Properties on/ { \
		dir = $3; \
		gsub("^.|.:\r?$", "", dir); \
		ignorefile = dir "/.gitignore"; \
		if (ignorefile != "/.gitignore") \
			print "# generated by git-ontop\n/.gitignore" > ignorefile; \
	} \
	/^    [^ ]/ { \
		untrackedfile = $1; \
		if (ignorefile != "/.gitignore") \
			print "/" untrackedfile >> ignorefile; \
	} \
'

# global ignores
echo ".svn/" >> .gitignore

# add all files belonging to the Subversion repository
# spaces in filenames are handled
# do not pass all files in one invocation to prevent 'git add' failing: /libexec/git-core/git: Bad file number
IFS=$'\n'
FILES_PACKET=()
CNT=0
for i in $(LANG=C svn status -v | grep -v "^Performing\|^?\|^X\|^$\|^.$" | awk '{ if ($4 != ".") { $1=$2=$3=""; sub(/^ +/, ""); print $0 } }')
do
	if [ ! -d "$i" ]
	then
		FILES_PACKET+=("$i")
		CNT=$((CNT + 1))

		if [ $CNT -gt 100 ]
		then
			git add -f ${FILES_PACKET[@]}
			FILES_PACKET=()
			CNT=0
		fi
	fi
done
git add -f ${FILES_PACKET[@]}

git add -u
git commit -m"SVN revision $(LANG=C svn info | awk '/^Revision:/ { print $2 }')"