scripts: make generate_git do something

Generate a git tree from the ltsi queue of patches, by
only using git commands.

Support a quasi intelligent auto resume feature in the case
where a patch fails to apply, by using the upstream ID (if
present) to determine the current patch used for the HEAD
commit.  If that fails, use a diffstat comparison to try
and find the current patch.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 118 insertions, 1 deletions

diff --git a/scripts/generate_git b/scripts/generate_git
index 3c09e7acaca40..cb1053d2ef881 100755
--- a/scripts/generate_git
+++ b/scripts/generate_git
@@ -9,4 +9,121 @@
 #
 #
 
-echo "Not implemented yet, check back soon."
+UPSTREAM="git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git"
+if [ "$1" = "-a" ]; then
+	AUTORESUME=1
+	shift
+fi
+
+DIR=`dirname $0 |sed 's/scripts$//'`
+SERIES=$DIR/series
+
+if [ -z "$SERIES" ]; then
+	echo Cant find series file at $SERIES
+	exit 1
+fi
+
+if [ -n "$2" ];then
+	START=$2
+fi
+
+diffstat --help > /dev/null 2>&1
+if [ $? != 0 ]; then
+	echo It appears you dont have diffstat installed.
+	echo Please install it.
+	exit 1
+fi
+
+if [ ! -d .git ]; then
+	echo There does not appear to be a git tree in this dir.
+	echo You need a copy of:
+	echo $UPSTREAM
+	echo as a baseline.
+	exit 1
+fi
+
+KVER=`cat $DIR/KERNEL_VERSION`
+git rev-parse -q --verify v$KVER > /dev/null
+if [ $? != 0 ]; then
+	echo There is no \"v$KVER\" in this git repository.  Perhaps pull from:
+	echo $UPSTREAM
+	echo to get this tag?
+	exit 1
+fi
+
+if [ -n "$AUTORESUME" ]; then
+	PARENT=`git show|grep ommit|grep 'pstream\|herry\|tip'|sed 's/.* \([0-9a-f]\+\).*/\1/'`
+	CLEN=`echo $PARENT|wc -c`
+	if [ $CLEN -ne 41 ]; then
+		echo Failed to autodetect resume point -- no parent ID
+		echo falling back to diffstat detection
+		DS1=`mktemp`
+		DS2=`mktemp`
+		git show | diffstat -p0 > $DS1
+		for i in $DIR/*\.patch ; do
+			cat $i | diffstat -p0 > $DS2
+			cmp -s $DS1 $DS2
+			if [ $? = 0 ]; then
+				START=$i
+				break
+			fi
+		done
+		rm $DS1 $DS2
+		if [ -z "$START" ]; then
+			echo diffstat detection failed
+			exit 1
+		fi
+	fi
+
+	if [ -z "$START" ]; then
+		START=`grep -l $PARENT $DIR/patches.*/*`
+	fi
+
+	if [ -z "$START" ]; then
+		echo Failed to autodetect resume point - no matching filename
+		echo for patch that created current HEAD commit $PARENT
+		exit 1
+	fi
+
+	START=`basename $START`
+	echo resuming from current \"$START\"
+fi
+
+if [ -z "$START" ]; then
+	echo creating branch "$KVER-ltsi"
+	git checkout -b $KVER-ltsi v$KVER
+	if [ $? != 0 ]; then
+		echo Creation of branch $KVER-ltsi failed
+		exit 1
+	fi
+fi
+
+COUNT=`cat $SERIES | grep '^[a-zA-Z0-9_]'|wc -l`
+APPLIED=0
+
+for i in `cat $SERIES | grep '^[a-zA-Z0-9_]'`
+do
+
+	APPLIED=$[$APPLIED+1]
+
+	if [ -n "$START" ]; then
+		if [ "$START" != "$i" ];then
+			continue
+		else
+			START=""
+			continue
+		fi
+	fi
+
+	if [ ! -f "$DIR/$i" ];then
+		echo $DIR/$i doesnt exist
+		break
+	fi
+
+	echo -n "($APPLIED/$COUNT) "
+	git am $DIR/$i
+	if [ $? != 0 ];then
+		echo git am of $i failed. STBU.
+		exit 1
+	fi
+done