From 64a4b761a009768d3ef7c8e3bc4692d4e95772f9 Mon Sep 17 00:00:00 2001
From: josch <j.schauer@email.de>
Date: Thu, 5 Jun 2014 14:14:03 +0200
Subject: [PATCH] initial commit

---
 findunusedbd.sh | 103 ++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 103 insertions(+)
 create mode 100755 findunusedbd.sh

diff --git a/findunusedbd.sh b/findunusedbd.sh
new file mode 100755
index 0000000..d002f58
--- /dev/null
+++ b/findunusedbd.sh
@@ -0,0 +1,103 @@
+#!/bin/sh -ex
+# start this script without arguments and then start sbuild as:
+#
+#    sbuild --chroot-setup-commands='/home/josch/prebuildcmd.sh chroot-setup' --pre-realbuild-commands='/home/josch/prebuildcmd.sh pre-realbuild' --post-realbuild-commands='/home/josch/prebuildcmd.sh post-realbuild'
+
+if [ "$#" -ne 1 ]; then
+	rm -rf /home/josch/myfifo /home/josch/myfifo2 /tmp/pkglists
+	mkfifo /home/josch/myfifo
+	mkfifo /home/josch/myfifo2
+	mkdir -p /tmp/pkglists
+	# strip the architecture qualifier
+	cat /home/josch/myfifo | cut -d ':' -f 1 | sort > initialselection.list
+	echo > /home/josch/myfifo2
+	cat /home/josch/myfifo | cut -d ':' -f 1 | sort > fullselection.list
+	echo > /home/josch/myfifo2
+	# get all packages that were installed on top of the base packages
+	comm -13 initialselection.list fullselection.list > bdselection.list
+	while true; do
+		pkgname=`cat /home/josch/myfifo | cut -d ':' -f 1`
+		echo > /home/josch/myfifo2
+		# end loop when packagename is empty
+		[ -z "$pkgname" ] && break
+		# check if the package was installed as its build dependencies
+		if grep --line-regexp $pkgname bdselection.list; then
+			cat /home/josch/myfifo | sort > "/tmp/pkglists/$pkgname"
+		else
+			cat /home/josch/myfifo > /dev/null
+		fi
+		echo > /home/josch/myfifo2
+	done
+	cat /home/josch/myfifo | sed 's/, \+/\n/'g \
+		| sed 's/\([a-zA-Z0-9][a-zA-Z0-9+.-]*\).*/\1/' \
+		> /tmp/sbuild-dummy-depends
+	echo > /home/josch/myfifo2
+	SCHROOT_SESSION_ID=`cat /home/josch/myfifo`;
+	echo > /home/josch/myfifo2
+
+	# start fatrace in the mounted directory
+	(
+		cd /var/lib/schroot/mount/$SCHROOT_SESSION_ID;
+		sudo fatrace --current-mount > /home/josch/fatrace.log &
+		FATRACE_PID=$!;
+		cat /home/josch/myfifo > /dev/null;
+		echo > /home/josch/myfifo2
+		sudo kill $FATRACE_PID;
+	)
+
+	# clean up the fatrace log to only include unique paths
+	sed 's/\/var\/lib\/schroot\/mount\/[^\/]\+//' /home/josch/fatrace.log \
+		| awk '{ print $3; }' \
+		| grep -v ^/build \
+		| sort \
+		| uniq \
+		> accessed.log
+	# now get all packages in /tmp/pkglists that have files that never appear in the collected trace
+	while read pkg; do
+		# FIXME: the following cannot handle dependencies on virtual packages
+		[ -z "`comm -12 accessed.log /tmp/pkglists/$pkg`" ] \
+			&& grep --line-regexp "$pkg" /tmp/sbuild-dummy-depends || true
+	done > unneededdepends.list < bdselection.list
+else
+	case "$1" in
+		chroot-setup)
+			env
+			dpkg --get-selections | awk '{ print $1; }' > /home/josch/myfifo
+			cat /home/josch/myfifo2 > /dev/null
+			;;
+		pre-realbuild)
+			# get the current selection so that the parent script can find the additional packages that were installed
+			dpkg --get-selections | awk '{ print $1; }' > /home/josch/myfifo
+			cat /home/josch/myfifo2 > /dev/null
+			# output the files belonging to all packages
+			for pkg in `dpkg --get-selections | awk '{ print $1; }'`; do
+				echo $pkg > /home/josch/myfifo
+				cat /home/josch/myfifo2 > /dev/null
+				dpkg -L $pkg > /home/josch/myfifo
+				cat /home/josch/myfifo2 > /dev/null
+			done
+			# output an empty line to indicate the end
+			echo > /home/josch/myfifo
+			cat /home/josch/myfifo2 > /dev/null
+			# output the dependencies of the sbuild dummy package
+			dpkg --get-selections | awk '{ print $1; }' \
+				| grep sbuild-build-depends \
+				| grep -v sbuild-build-depends-core-dummy \
+				| grep -v sbuild-build-depends-essential-dummy \
+				| grep -v sbuild-build-depends-lintian-dummy \
+				| xargs -I {} dpkg-query --showformat='${Depends}\n' --show {} \
+				> /home/josch/myfifo
+			cat /home/josch/myfifo2 > /dev/null
+			# output the schroot id to start tracing
+			echo $SCHROOT_SESSION_ID > /home/josch/myfifo
+			cat /home/josch/myfifo2 > /dev/null
+			;;
+		post-realbuild)
+			echo "done" > /home/josch/myfifo
+			cat /home/josch/myfifo2 > /dev/null
+			;;
+		*)
+			echo "invalid argument: $1" >&2
+			;;
+	esac
+fi