[Mageia-dev] Script for rediffing patches

Sun Mar 31 23:17:17 CEST 2013

Hi all,
+
+Colin's question reminded me of another hacky script I use for rediffing
+patches. I had planned to clean it up but clearly that is never going to
+happen, so I may as well provide it here in case someone else finds it
+useful or even wants to make a clean version...
+
+It has accumulated hacks on top of hacks over the years to handle lots
+of special cases (%apply_patches, Patch: foo.patch, concatenated
+patches, tarballs containing .orig files etc.) with little regard to
+readability, but it has worked well for me...
+
+Usage, in pkg checkout:
+$ rediffpatches SOURCES/foobar-1.2.tar.bz2
+
+It rediffs all patches automatically, and in case of nonmergeable
+conflict it will drop you to shell to apply the patch manually, and will
+continue after you exit.
+
+Of course you still *have to* manually review *all* the changes made as
+always, but it still makes the work progress faster (especially in pkgs
+with lots of patches).
+
+-- 
+Anssi Hannula
+-------------- next part --------------
+#!/bin/bash
+allow_fastmode=1
+[ -f "$1" ] || exit 1
+tarball=$(readlink -f $1)
+[ -d ../SPECS ] && cd ../SPECS
+[ -d SPECS ] && cd SPECS
+name=$(dirname $PWD | sed s,.*/,,)
+spec=$(readlink -f $name.spec)
+[ -e $spec ] || exit 1
+sourcedir=$(readlink -f $PWD/../SOURCES)
+#source=$sourcedir/$(awk '/^Source.*:/ { print $2 }' $spec | head -n1)
+source=$tarball
+rm -rf .rediff
+mkdir .rediff
+cd .rediff
+tar -xf $source
+for file in ./*; do
+	if [ -L "$file" ]; then
+		rm -vf $file
+	fi
+done
+workdir=$(echo */)
+workdir=${workdir%/}
+plain_magic=9999924
+for patch in $(sed "s/^[Pp]atch:/Patch$plain_magic:/" $spec | sed -n -r "/^[Pp]atch.*:/s,^[Pp]atch([0-9]+):\s*(.+)$,\1=\2,p" | sed "s,%{name},${name},"); do
+	eval patch$patch
+done
+ext=.orig
+[ $(find */ -name '*.orig' | wc -l) -eq 0 ] || ext=.orig2
+apply_magic=
+egrep -q '^%{?apply_patches}?' $spec && apply_magic=1
+for patch in $(sed -r $([ -n "$apply_magic" ] && echo "-e s/^[Pp]atch([0-9]*):.*$/%patch\1/") -e "s/^%patch[$ ]/%patch$plain_magic /" $spec | sed -n -r "/^%patch[0-9]+/s,^%patch([0-9]+)\s*(\-p[0-9])?.*$,\1:\2,p"); do
+	pvar=${patch#*:}
+	[ -n "$pvar" ] || pvar=-p1
+	patch=${patch%:*}
+	eval patch=\$patch$patch
+	patch="$sourcedir/${patch##*/}"
+	while echo "$patch" | grep -q '%'; do
+		variable=$(echo "$patch" | sed -r 's,^.*%\{?([a-zA-Z0-9_]+)\}?.*$,\1,')
+		value=$(awk "/^%define[[:space:]]+$variable[[:space:]]+/ { print \$3 }" $spec)
+		patch=$(echo "$patch" | sed -r "s,%\{?$variable\}?,$value,")
+	done
+	if patch -d */ -F0 --dry-run -i $patch $pvar >/dev/null; then
+		echo "Up-to-date: $patch"
+		patch -d */ -F0 --no-backup-if-mismatch -i $patch $pvar -s || exit 1
+		continue
+	fi
+	echo -n "Rediffing $patch... "
+	gawk '{ if ($1 == "Index:" || $1 == "diff" || $1 == "---") exit; print; }' $patch > pretext.txt
+	fastmode=1
+	if [ -n "$allow_fastmode" ]; then
+		if [ $(cat $patch | egrep '^(\+\+\+|---) ' | grep -v '^... /dev/null' | cut -f1 | sed -r 's, [^/]+/, ,' | sort | uniq -d | wc -l) -ne 0 ]; then
+			echo -n "combined patch detected, disabling fast mode... "
+			fastmode=
+		elif [ $(cat $patch | egrep '^(\+\+\+|---) ' | grep -c '^... /dev/null') -ne 0 ]; then
+			echo -n "files added or removed, disabling fast mode... "
+			fastmode=
+	
+		elif ! patch -d $workdir -F2 -i $patch --dry-run $pvar >/dev/null; then
+			echo -n "patch does not apply, disabling fast mode... "
+			fastmode=
+		fi
+	fi
+
+	pstatus=0
+	if [ -n "$fastmode" -a -n "$allow_fastmode" ]; then
+		patch -d */ -F2 -V simple -b -z $ext -i $patch $pvar -s || exit 1
+	else
+		cp -a $workdir newdir
+		patch -d newdir -F2 --merge=diff3 -V simple -z $ext -i $patch $pvar > out.txt
+		pstatus=$?
+	fi
+	if [ $pstatus -ne 0 ]; then
+		echo
+		echo "Patch $patch did not apply cleanly, dropping to shell."
+		echo "Apply manually and then exit, or abort with \"exit 1\"."
+		cd newdir
+		cat ../out.txt
+		bash
+		ret=$?
+		[ $ret -ne 0 ] && echo "Aborted." && exit $ret
+		cd ..
+		echo -n "Assuming clean state, continuing... "
+	fi
+	rm -f out.txt
+	if [ -n "$fastmode" -a -n "$allow_fastmode" ]; then
+		gendiff $workdir $ext > $patch.new
+	else
+		diff -Nurpa -x '*~' -x '*.orig' -x '*.rej' -x '*.swp' $workdir newdir | sed -e "s,^+++ newdir/,+++ $workdir/," -e "s,^\(diff.* \)newdir/,\1$workdir/,"  > $patch.new
+		rm -rf newdir
+		patch -d $workdir -F0 -i $patch.new -p1 -s || exit 1
+	fi
+	backupname=$patch.origsvn
+	if [ -e $backupname ]; then
+		i=1
+		while [ -e $backupname.$i ]; do
+			i=$((i+1))
+		done
+		backupname=$backupname.$i
+	fi
+	mv $patch $backupname
+	cat pretext.txt $patch.new > $patch
+	rm $patch.new
+	find . -name "*${ext}" -delete
+	echo "OK"
+done
+cd ..
+rm -rf .rediff
+