1 files changed, 121 insertions, 0 deletions
diff --git a/scripts/dscextract.sh b/scripts/dscextract.sh
new file mode 100755
index 0000000..78e2334
--- /dev/null
+++ b/scripts/dscextract.sh
@@ -0,0 +1,121 @@
+#!/bin/sh
+
+#   dscextract.sh - Extract a single file from a Debian source package
+#   Copyright (C) 2011 Christoph Berg <myon@debian.org>
+#
+#   This program is free software; you can redistribute it and/or modify
+#   it under the terms of the GNU General Public License as published by
+#   the Free Software Foundation; either version 2 of the License, or
+#   (at your option) any later version.
+#
+#   This program is distributed in the hope that it will be useful,
+#   but WITHOUT ANY WARRANTY; without even the implied warranty of
+#   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+#   GNU General Public License for more details.
+#
+#   You should have received a copy of the GNU General Public License
+#   along with this program; if not, write to the Free Software
+#   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
+
+set -eu
+
+PROGNAME=${0##*/}
+
+die() {
+	echo "$*" >&2
+	exit 2
+}
+
+setzip() {
+	case $1 in
+		*.gz) ZIP=--gzip ;;
+		*.xz) ZIP=--xz ;;
+		*.lzma) ZIP=--lzma ;;
+		*.bz2) ZIP=--bzip2 ;;
+	esac
+}
+
+FAST=""
+while getopts "f" opt ; do
+	case $opt in
+		f) FAST=yes ;;
+		*) exit 2 ;;
+	esac
+done
+# shift away args
+shift $(($OPTIND - 1))
+
+[ $# = 2 ] || die "Usage: $PROGNAME <dsc> <file>"
+DSC="$1"
+test -e "$DSC" || die "$DSC not found"
+FILE="$2"
+
+DSCDIR=$(dirname "$DSC")
+WORKDIR=$(mktemp -d --tmpdir dscextract.XXXXXX)
+trap 'rm -rf "$WORKDIR"' EXIT
+
+if DIFFGZ=$(grep -E '^ [0-9a-f]{32,64} [0-9]+ [^ ]+\.diff\.(gz|xz|lzma|bz2)$' "$DSC") ; then
+	DIFFGZ=$(echo "$DIFFGZ" | cut -d ' ' -f 4 | head -n 1)
+	test -e "$DSCDIR/$DIFFGZ" || die "$DSCDIR/$DIFFGZ: not found"
+	filterdiff -p1 -i "$FILE" -z "$DSCDIR/$DIFFGZ" > "$WORKDIR/patch"
+	if test -s "$WORKDIR/patch" ; then
+		# case 1: file found in .diff.gz
+		if ! grep -q '^@@ -0,0 ' "$WORKDIR/patch" ; then
+			# case 1a: patch requires original file
+			ORIGTGZ=$(grep -E '^ [0-9a-f]{32,64} [0-9]+ [^ ]+\.orig\.tar\.(gz|xz|lzma|bz2)$' "$DSC") || die "no orig.tar.* found in $DSC"
+			ORIGTGZ=$(echo "$ORIGTGZ" | cut -d ' ' -f 4 | head -n 1)
+			setzip $ORIGTGZ
+			test -e "$DSCDIR/$ORIGTGZ" || die "$DSCDIR/$ORIGTGZ not found"
+			tar --extract --to-stdout $ZIP --file "$DSCDIR/$ORIGTGZ" --wildcards "*/$FILE" > "$WORKDIR/output" 2>/dev/null || :
+			test -s "$WORKDIR/output" || die "$FILE not found in $DSCDIR/$ORIGTGZ, but required by patch"
+		fi
+		patch --silent "$WORKDIR/output" < "$WORKDIR/patch"
+		test -s "$WORKDIR/output" || die "patch $FILE did not produce any output"
+		cat "$WORKDIR/output"
+		exit 0
+	elif [ "$FAST" ] ; then
+		# in fast mode, don't bother looking into .orig.tar.gz
+		exit 1
+	fi
+fi
+
+if DEBIANTARGZ=$(grep -E '^ [0-9a-f]{32,64} [0-9]+ [^ ]+\.debian\.tar\.(gz|xz|lzma|bz2)$' "$DSC") ; then
+	case $FILE in
+		debian/*)
+			DEBIANTARGZ=$(echo "$DEBIANTARGZ" | cut -d ' ' -f 4 | head -n 1)
+			test -e "$DSCDIR/$DEBIANTARGZ" || die "$DSCDIR/$DEBIANTARGZ not found"
+			setzip $DEBIANTARGZ
+			tar --extract --to-stdout $ZIP --file "$DSCDIR/$DEBIANTARGZ" "$FILE" > "$WORKDIR/output" 2>/dev/null || :
+			test -s "$WORKDIR/output" || exit 1
+			# case 2a: file found in .debian.tar.gz
+			cat "$WORKDIR/output"
+			exit 0
+			# for 3.0 format, no need to look in other places here
+			;;
+		*)
+			ORIGTGZ=$(grep -E '^ [0-9a-f]{32,64} [0-9]+ [^ ]+\.orig\.tar\.(gz|xz|lzma|bz2)$' "$DSC") || die "no orig.tar.gz found in $DSC"
+			ORIGTGZ=$(echo "$ORIGTGZ" | cut -d ' ' -f 4 | head -n 1)
+			test -e "$DSCDIR/$ORIGTGZ" || die "$DSCDIR/$ORIGTGZ not found"
+			setzip $ORIGTGZ
+			tar --extract --to-stdout $ZIP --file "$DSCDIR/$ORIGTGZ" --wildcards --no-wildcards-match-slash "*/$FILE" > "$WORKDIR/output" 2>/dev/null || :
+			test -s "$WORKDIR/output" || exit 1
+			# case 2b: file found in .orig.tar.gz
+			# TODO: apply patches from debian.tar.gz
+			cat "$WORKDIR/output"
+			exit 0
+			;;
+	esac
+fi
+
+if TARGZ=$(grep -E '^ [0-9a-f]{32,64} [0-9]+ [^ ]+\.tar\.(gz|xz|lzma|bz2)$' "$DSC") ; then
+	TARGZ=$(echo "$TARGZ" | cut -d ' ' -f 4 | head -n 1)
+	test -e "$DSCDIR/$TARGZ" || die "$DSCDIR/$TARGZ not found"
+	setzip $TARGZ
+	tar --extract --to-stdout $ZIP --file "$DSCDIR/$TARGZ" --wildcards --no-wildcards-match-slash "*/$FILE" > "$WORKDIR/output" 2>/dev/null || :
+	test -s "$WORKDIR/output" || exit 1
+	# case 3: file found in .tar.gz or .orig.tar.gz
+	cat "$WORKDIR/output"
+	exit 0
+fi
+
+exit 1