Add `debian/patch2quilt' script

It can automate cherry-picking upstream patches into a quilt series patch.

Signed-off-by: Frank Terbeck <ft@bewatermyfriend.org>

1 files changed, 99 insertions, 0 deletions

diff --git a/debian/patch2quilt b/debian/patch2quilt
new file mode 100755
index 000000000..8a5c67305
--- /dev/null
+++ b/debian/patch2quilt
@@ -0,0 +1,99 @@
+#!/bin/sh
+
+# patch2quilt
+# Copyright (c) 2011, Frank Terbeck <ft@bewatermyfriend.org>
+#
+# Permission to use, copy, modify, and/or distribute this software for any
+# purpose with or without fee is hereby granted, provided that the above
+# copyright notice and this permission notice appear in all copies.
+#
+# THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+# WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+# MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+# ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+# WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+# ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+# OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+#
+# Often, we may want to backport a patch from upstream to our package. If
+# that's just a matter of cherry-picking a patch from upstream, this script can
+# help. We don't really want to git cherry-pick, but rather add a new patch to
+# our quilt series. In short, this script automates doing that.
+#
+# Call it like this:
+#   % ./debian/patch2quilt ../0000-git-patch.patch 0010-quilt-patch.diff
+#
+# Where `../0000-git-patch.patch' is a patch from git; `0010-quilt-patch.diff'
+# is the to-be-added quilt patch. The script now does this:
+#
+#  - Reset and clean the repository to a clean state.
+#  - Push the entire quilt series.
+#  - Add `0010-quilt-patch.diff' as a new patch in the quilt series.
+#  - Check which files are touched by `../0000-git-patch.patch' and add those
+#    to the newly added quilt patch.
+#  - Apply the git patch.
+#  - Refresh the quilt patch.
+#  - Pop the entire quilt series again.
+#  - Open the new quilt patch in ${VISUAL:-${EDITOR:-vi}} to add annotation.
+#
+# That's all.
+#
+# Note: If the patch file is located in the current repository, it will be
+#       deleted when the repository is cleaned up initially. So don't do that.
+#
+#       Also, if we're just cherry picking stuff from upstream git, there are
+#       likely changes to ChangeLog, which will not apply cleanly. Just throw
+#       away all such hunks from the patch beforehand.
+#
+# `patch2quilt' requires `quilt', `git' and `diffstat' available.
+#
+# Call this script *only* from the git repository's base directory.
+
+QUILT_PATCHES=debian/patches
+export QUILT_PATCHES
+
+if [ ! -d "${QUILT_PATCHES}" ]; then
+    printf 'No such directory: `%s'\''\n' "${QUILT_PATCHES}"
+    printf 'Quilt patches directory not found. Giving up.\n'
+    exit 1
+fi
+
+if [ $# -ne 2 ]; then
+    printf 'usage: patch2quilt <git-patch> <quilt-patch>\n'
+    exit 1
+fi
+
+gitpatch="$1"
+quiltpatch="$2"
+
+git clean -xdf || exit 1
+git reset --hard || exit 1
+
+quilt push -a || exit 1
+
+quilt new "${quiltpatch}" || exit 1
+
+diffstat -l "${gitpatch}" | while IFS= read -r file; do
+    quilt add "${file}" || exit 1
+done
+
+git apply "${gitpatch}" || exit 1
+
+quilt refresh || exit 1
+
+quilt pop -a || exit 1
+
+${VISUAL:-${EDITOR:-vi}} "${QUILT_PATCHES}/${quiltpatch}"
+
+printf -- '\n---------------------------------------'
+printf -- '---------------------------------------\n'
+printf '\n  New quilt patch `%s'\'' added.  You\n' "${quiltpatch}"
+printf '  should add it and its series file to git and commit the result.\n'
+printf '\n  Like this:\n\n'
+printf '    %% git add "%s"\n' "${QUILT_PATCHES}/series"
+printf '    %% git add "%s"\n' "${QUILT_PATCHES}/${quiltpatch}"
+printf '    %% git commit\n'
+printf '\n  Write a useful commit message.'
+printf '  Don'\''t forget `Closes:'\'' mentions!\n\n'
+
+exit 0