add changes from actual run

README.md

@@ -20,5 +20,28 @@ which can be added to sbuild by applying
 Any unused dependencies can then be found by investigating the file
 `unneededdepends.list`.
 
-Bugs: when investigating which build dependencies are unused, virtual packages
-are not taken into account.
+The process can be automated for multiple packages by passing `dsc` files to
+`run.sh`:
+
+	$ ./run.sh ../mysources/*.dsc
+
+This script will put the successful builds in `buildsuccess.list` and the found
+unused build dependencies as `*.unusedbd` for each `dsc` file in the current
+directory. A second pass on the successfully built `dsc` files will then check
+each of the found unused build dependencies for their validity by replacing
+them by an empty equivs package one after another. The results of that run are
+stored in `*.unusedbd.real` files for each `dsc` file in the current directory.
+The `run.sh` script expects to find `findunusedbd.sh` directly under `/home`.
+Best try this out in a chroot to not mess with the host system.
+
+Customize the schroot:
+
+	$ sbuild-shell source:sid-amd64-sbuild
+	$ echo 'Acquire::Check-Valid-Until "false";' > /etc/apt/apt.conf.d/80-nocheckvaliduntil
+	$ apt-get install equivs --no-install-recommends
+
+
+Bugs:
+ - when investigating which build dependencies are unused, virtual packages are not taken into account
+ - maybe the fake equivs package can be built outside the schroot to avoid the additional dependencies for installing equivs
+ - maybe equivs can be avoided altogether by finding a way to edit debian/control on the fly

findunusedbd.sh

@@ -1,52 +1,52 @@
 #!/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'
+#    sbuild --chroot-setup-commands='/home/prebuildcmd.sh chroot-setup' --pre-realbuild-commands='/home/prebuildcmd.sh pre-realbuild' --post-realbuild-commands='/home/prebuildcmd.sh post-realbuild'
 
-if [ "$#" -ne 1 ]; then
-	rm -rf /home/josch/myfifo /home/josch/myfifo2 /tmp/pkglists
-	mkfifo /home/josch/myfifo
-	mkfifo /home/josch/myfifo2
+if [ "$#" -eq 0 ]; then
+	rm -rf /home/myfifo /home/myfifo2 /tmp/pkglists
+	mkfifo /home/myfifo
+	mkfifo /home/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
+	cat /home/myfifo | cut -d ':' -f 1 | sort > initialselection.list
+	echo > /home/myfifo2
+	cat /home/myfifo | cut -d ':' -f 1 | sort > fullselection.list
+	echo > /home/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
+		pkgname=`cat /home/myfifo | cut -d ':' -f 1`
+		echo > /home/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"
+			cat /home/myfifo | sort > "/tmp/pkglists/$pkgname"
 		else
-			cat /home/josch/myfifo > /dev/null
+			cat /home/myfifo > /dev/null
 		fi
-		echo > /home/josch/myfifo2
+		echo > /home/myfifo2
 	done
-	cat /home/josch/myfifo | sed 's/, \+/\n/'g \
+	cat /home/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
+	echo > /home/myfifo2
+	SCHROOT_SESSION_ID=`cat /home/myfifo`;
+	echo > /home/myfifo2
 
 	# start fatrace in the mounted directory
 	(
 		cd /var/lib/schroot/mount/$SCHROOT_SESSION_ID;
-		sudo fatrace --current-mount > /home/josch/fatrace.log &
+		fatrace --current-mount > /home/fatrace.log &
 		FATRACE_PID=$!;
-		cat /home/josch/myfifo > /dev/null;
-		echo > /home/josch/myfifo2
-		sudo kill $FATRACE_PID;
+		cat /home/myfifo > /dev/null;
+		echo > /home/myfifo2
+		kill $FATRACE_PID;
 	)
 
 	# clean up the fatrace log to only include unique paths
-	sed 's/\/var\/lib\/schroot\/mount\/[^\/]\+//' /home/josch/fatrace.log \
+	sed 's/\/var\/lib\/schroot\/mount\/[^\/]\+//' /home/fatrace.log \
 		| awk '{ print $3; }' \
 		| grep -v ^/build \
 		| sort \
@@ -62,23 +62,23 @@ else
 	case "$1" in
 		chroot-setup)
 			env
-			dpkg --get-selections | awk '{ print $1; }' > /home/josch/myfifo
-			cat /home/josch/myfifo2 > /dev/null
+			dpkg --get-selections | awk '{ print $1; }' > /home/myfifo
+			cat /home/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
+			dpkg --get-selections | awk '{ print $1; }' > /home/myfifo
+			cat /home/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
+				echo $pkg > /home/myfifo
+				cat /home/myfifo2 > /dev/null
+				dpkg -L $pkg > /home/myfifo
+				cat /home/myfifo2 > /dev/null
 			done
 			# output an empty line to indicate the end
-			echo > /home/josch/myfifo
-			cat /home/josch/myfifo2 > /dev/null
+			echo > /home/myfifo
+			cat /home/myfifo2 > /dev/null
 			# output the dependencies of the sbuild dummy package
 			dpkg --get-selections | awk '{ print $1; }' \
 				| grep sbuild-build-depends \
@@ -86,15 +86,21 @@ else
 				| grep -v sbuild-build-depends-essential-dummy \
 				| grep -v sbuild-build-depends-lintian-dummy \
 				| xargs -I {} dpkg-query --showformat='${Depends}\n' --show {} \
-				> /home/josch/myfifo
-			cat /home/josch/myfifo2 > /dev/null
+				> /home/myfifo
+			cat /home/myfifo2 > /dev/null
 			# output the schroot id to start tracing
-			echo $SCHROOT_SESSION_ID > /home/josch/myfifo
-			cat /home/josch/myfifo2 > /dev/null
+			echo $SCHROOT_SESSION_ID > /home/myfifo
+			cat /home/myfifo2 > /dev/null
 			;;
 		post-realbuild)
-			echo "done" > /home/josch/myfifo
-			cat /home/josch/myfifo2 > /dev/null
+			echo "done" > /home/myfifo
+			cat /home/myfifo2 > /dev/null
+			;;
+		equivs)
+			pkgname="$2"
+			# create and install a package with same name and version but without dependencies
+			apt-cache show --no-all-versions $pkgname | grep -v "^Depends:" | grep -v "^Pre-Depends:" | equivs-build -
+			dpkg -i ${pkgname}_*.deb
 			;;
 		*)
 			echo "invalid argument: $1" >&2

run.sh

@@ -0,0 +1,38 @@
+#!/bin/sh -x
+
+if [ $# -eq 0 ]; then
+	echo "usage: $0 foo.dsc [bar.dsc ...]"
+	exit 1
+fi
+
+echo > buildsuccess.list
+for dsc in $1; do
+	echo $dsc
+	/home/findunusedbd.sh &
+	sbuild --no-arch-all \
+		--chroot-setup-commands='/home/findunusedbd.sh chroot-setup' \
+		--pre-realbuild-commands='/home/findunusedbd.sh pre-realbuild' \
+		--post-realbuild-commands='/home/findunusedbd.sh post-realbuild' \
+		"$dsc"
+	ret=$?
+	rm -f *.deb *.udeb *.changes
+	if [ $ret -eq 0 ] && [ -s unneededdepends.list ]; then
+		mv unneededdepends.list `basename $dsc .dsc`.unusedbd
+		echo $dsc >> buildsuccess.list
+	fi
+done
+
+while read dscname; do
+	echo $dscname
+	unusedbdname=`basename $dscname .dsc`.unusedbd
+	while read bd; do
+		# now run sbuild with "findunusedbd.sh equivs" creating a fake equivs package
+		sbuild --no-arch-all \
+			--chroot-setup-commands="/home/findunusedbd.sh equivs $bd" \
+			"$dscname"
+		if [ $? -eq 0 ]; then
+			echo $bd >> "${unusedbdname}".real
+		fi
+		rm -f *.deb *.udeb *.changes
+	done < $unusedbdname
+done < buildsuccess.list