8 files changed, 489 insertions, 206 deletions

diff --git a/doc/pacman.conf.5.txt b/doc/pacman.conf.5.txt
index fa212947..2f1fe3df 100644
--- a/doc/pacman.conf.5.txt
+++ b/doc/pacman.conf.5.txt
@@ -144,7 +144,7 @@ Options
 
 *UseDelta*::
 	Download delta files instead of complete packages if possible.  Requires
-	the xdelta program to be installed.
+	the xdelta3 program to be installed.
 
 *TotalDownload*::
 	When downloading, display the amount downloaded, download rate, ETA,
diff --git a/lib/libalpm/delta.c b/lib/libalpm/delta.c
index 9e4bcb42..de5dd601 100644
--- a/lib/libalpm/delta.c
+++ b/lib/libalpm/delta.c
@@ -21,6 +21,7 @@
 
 #include <stdlib.h>
 #include <string.h>
+#include <stdint.h> /* intmax_t */
 #include <limits.h>
 #include <sys/types.h>
 #include <regex.h>
@@ -215,13 +216,13 @@ off_t _alpm_shortest_delta_path(alpm_list_t *deltas,
 		return(bestsize);
 	}
 
-	_alpm_log(PM_LOG_DEBUG, "started delta shortest-path search\n");
+	_alpm_log(PM_LOG_DEBUG, "started delta shortest-path search for '%s'\n", to);
 
 	vertices = delta_graph_init(deltas);
 
 	bestsize = delta_vert(vertices, to, &bestpath);
 
-	_alpm_log(PM_LOG_DEBUG, "delta shortest-path search complete\n");
+	_alpm_log(PM_LOG_DEBUG, "delta shortest-path search complete : '%jd'\n", (intmax_t)bestsize);
 
 	alpm_list_free_inner(vertices, _alpm_graph_free);
 	alpm_list_free(vertices);
diff --git a/lib/libalpm/sync.c b/lib/libalpm/sync.c
index fca96d8f..49ea3c27 100644
--- a/lib/libalpm/sync.c
+++ b/lib/libalpm/sync.c
@@ -27,6 +27,7 @@
 #include <stdio.h>
 #include <fcntl.h>
 #include <string.h>
+#include <stdint.h> /* intmax_t */
 #include <unistd.h>
 #include <time.h>
 #include <dirent.h>
@@ -387,8 +388,8 @@ static int compute_download_size(pmpkg_t *newpkg)
 		size = alpm_pkg_get_size(newpkg);
 	}
 
-	_alpm_log(PM_LOG_DEBUG, "setting download size %lld for pkg %s\n",
-			(long long)size, alpm_pkg_get_name(newpkg));
+	_alpm_log(PM_LOG_DEBUG, "setting download size %jd for pkg %s\n",
+			(intmax_t)size, alpm_pkg_get_name(newpkg));
 
 	newpkg->download_size = size;
 	return(0);
@@ -679,6 +680,12 @@ off_t SYMEXPORT alpm_pkg_download_size(pmpkg_t *newpkg)
 	return(newpkg->download_size);
 }
 
+static int endswith(char *filename, char *extension)
+{
+	char *s = filename + strlen(filename) - strlen(extension);
+	return (strcmp(s, extension) == 0);
+}
+
 /** Applies delta files to create an upgraded package file.
  *
  * All intermediate files are deleted, leaving only the starting and
@@ -724,16 +731,18 @@ static int apply_deltas(pmtrans_t *trans)
 			CALLOC(to, len, sizeof(char), RET_ERR(PM_ERR_MEMORY, 1));
 			snprintf(to, len, "%s/%s", cachedir, d->to);
 
-			/* an example of the patch command: (using /cache for cachedir)
-			 * xdelta patch /path/to/pacman_3.0.0-1_to_3.0.1-1-i686.delta \
-			 *              /path/to/pacman-3.0.0-1-i686.pkg.tar.gz       \
-			 *              /cache/pacman-3.0.1-1-i686.pkg.tar.gz
-			 */
-
 			/* build the patch command */
-			snprintf(command, PATH_MAX, "xdelta patch %s %s %s", delta, from, to);
+			/* compression command */
+			char *compress = "cat";
+			if(endswith(to, ".gz")) {
+				compress = "gzip -n";
+			} else if(endswith(to, ".bz2")) {
+				compress = "bzip";
+			}
+			/* -R for disabling external recompression, -c for sending to stdout */
+			snprintf(command, PATH_MAX, "xdelta3 -d -q -R -c -s %s %s | %s > %s", from, delta, compress, to);
 
-			_alpm_log(PM_LOG_DEBUG, _("command: %s\n"), command);
+			_alpm_log(PM_LOG_DEBUG, "command: %s\n", command);
 
 			EVENT(trans, PM_TRANS_EVT_DELTA_PATCH_START, d->to, d->delta);
 
@@ -847,29 +856,31 @@ int _alpm_sync_commit(pmtrans_t *trans, pmdb_t *db_local, alpm_list_t **data)
 
 				fname = alpm_pkg_get_filename(spkg);
 				ASSERT(fname != NULL, RET_ERR(PM_ERR_PKG_INVALID_NAME, -1));
-				if(spkg->download_size != 0) {
-					alpm_list_t *delta_path = spkg->delta_path;
-					if(delta_path) {
-						alpm_list_t *dlts = NULL;
-
-						for(dlts = delta_path; dlts; dlts = dlts->next) {
-							pmdelta_t *d = dlts->data;
-
-							if(d->download_size != 0) {
-								/* add the delta filename to the download list if
-								 * it's not in the cache */
-								files = alpm_list_add(files, strdup(d->delta));
-							}
-
-							/* keep a list of the delta files for md5sums */
-							deltas = alpm_list_add(deltas, d);
+				alpm_list_t *delta_path = spkg->delta_path;
+				if(delta_path) {
+					/* using deltas */
+					alpm_list_t *dlts = NULL;
+
+					for(dlts = delta_path; dlts; dlts = dlts->next) {
+						pmdelta_t *d = dlts->data;
+
+						if(d->download_size != 0) {
+							/* add the delta filename to the download list if needed */
+							files = alpm_list_add(files, strdup(d->delta));
 						}
 
-					} else {
-						/* not using deltas, so add the file to the download list */
+						/* keep a list of all the delta files for md5sums */
+						deltas = alpm_list_add(deltas, d);
+					}
+
+				} else {
+					/* not using deltas */
+					if(spkg->download_size != 0) {
+						/* add the filename to the download list if needed */
 						files = alpm_list_add(files, strdup(fname));
 					}
 				}
+
 			}
 		}
 
@@ -890,37 +901,34 @@ int _alpm_sync_commit(pmtrans_t *trans, pmdb_t *db_local, alpm_list_t **data)
 		handle->totaldlcb(0);
 	}
 
-	if(handle->usedelta) {
+	/* if we have deltas to work with */
+	if(handle->usedelta && deltas) {
 		int ret = 0;
-
-		/* only output if there are deltas to work with */
-		if(deltas) {
-			errors = 0;
-			/* Check integrity of deltas */
-			EVENT(trans, PM_TRANS_EVT_DELTA_INTEGRITY_START, NULL, NULL);
-
-			for(i = deltas; i; i = i->next) {
-				pmdelta_t *d = alpm_list_getdata(i);
-				const char *filename = alpm_delta_get_filename(d);
-				const char *md5sum = alpm_delta_get_md5sum(d);
-
-				if(test_md5sum(trans, filename, md5sum) != 0) {
-					errors++;
-					*data = alpm_list_add(*data, strdup(filename));
-				}
+		errors = 0;
+		/* Check integrity of deltas */
+		EVENT(trans, PM_TRANS_EVT_DELTA_INTEGRITY_START, NULL, NULL);
+
+		for(i = deltas; i; i = i->next) {
+			pmdelta_t *d = alpm_list_getdata(i);
+			const char *filename = alpm_delta_get_filename(d);
+			const char *md5sum = alpm_delta_get_md5sum(d);
+
+			if(test_md5sum(trans, filename, md5sum) != 0) {
+				errors++;
+				*data = alpm_list_add(*data, strdup(filename));
 			}
-			if(errors) {
-				pm_errno = PM_ERR_DLT_INVALID;
-				goto error;
-			}
-			EVENT(trans, PM_TRANS_EVT_DELTA_INTEGRITY_DONE, NULL, NULL);
+		}
+		if(errors) {
+			pm_errno = PM_ERR_DLT_INVALID;
+			goto error;
+		}
+		EVENT(trans, PM_TRANS_EVT_DELTA_INTEGRITY_DONE, NULL, NULL);
 
-			/* Use the deltas to generate the packages */
-			EVENT(trans, PM_TRANS_EVT_DELTA_PATCHES_START, NULL, NULL);
-			ret = apply_deltas(trans);
-			EVENT(trans, PM_TRANS_EVT_DELTA_PATCHES_DONE, NULL, NULL);
+		/* Use the deltas to generate the packages */
+		EVENT(trans, PM_TRANS_EVT_DELTA_PATCHES_START, NULL, NULL);
+		ret = apply_deltas(trans);
+		EVENT(trans, PM_TRANS_EVT_DELTA_PATCHES_DONE, NULL, NULL);
 
-		}
 		if(ret) {
 			pm_errno = PM_ERR_DLT_PATCHFAILED;
 			goto error;
diff --git a/scripts/.gitignore b/scripts/.gitignore
index f2f19fd8..eafc4930 100644
--- a/scripts/.gitignore
+++ b/scripts/.gitignore
@@ -3,3 +3,4 @@ pacman-optimize
 rankmirrors
 repo-add
 repo-remove
+pkgdelta
diff --git a/scripts/Makefile.am b/scripts/Makefile.am
index d6d9bb93..5a2b780c 100644
--- a/scripts/Makefile.am
+++ b/scripts/Makefile.am
@@ -8,12 +8,14 @@ bin_SCRIPTS = \
 OURSCRIPTS = \
 	makepkg \
 	pacman-optimize \
+	pkgdelta \
 	rankmirrors \
 	repo-add
 
 EXTRA_DIST = \
 	makepkg.sh.in \
 	pacman-optimize.sh.in \
+	pkgdelta.sh.in \
 	rankmirrors.py.in \
 	repo-add.sh.in
 
@@ -58,6 +60,7 @@ $(OURSCRIPTS): Makefile
 
 makepkg: $(srcdir)/makepkg.sh.in
 pacman-optimize: $(srcdir)/pacman-optimize.sh.in
+pkgdelta: $(srcdir)/pkgdelta.sh.in
 rankmirrors: $(srcdir)/rankmirrors.py.in
 repo-add: $(srcdir)/repo-add.sh.in
 repo-remove: $(srcdir)/repo-add.sh.in
diff --git a/scripts/makepkg.sh.in b/scripts/makepkg.sh.in
index 3070c66e..97acfb49 100644
--- a/scripts/makepkg.sh.in
+++ b/scripts/makepkg.sh.in
@@ -974,25 +974,34 @@ create_package() {
 	# tar it up
 	msg2 "$(gettext "Compressing package...")"
 
-	local TAR_OPT
 	case "$PKGEXT" in
-		*tar.gz)  TAR_OPT="z" ;;
-		*tar.bz2) TAR_OPT="j" ;;
+		*tar.gz)  EXT=${PKGEXT%.gz} ;;
+		*tar.bz2) EXT=${PKGEXT%.bz2} ;;
 		*) warning "$(gettext "'%s' is not a valid archive extension.")" \
-		"$PKGEXT" ;;
+		"$PKGEXT" ; EXT=$PKGEXT ;;
 	esac
+	local pkg_file="$PKGDEST/${nameofpkg}-${pkgver}-${pkgrel}-${CARCH}${EXT}"
 
-	local pkg_file="$PKGDEST/${nameofpkg}-${pkgver}-${pkgrel}-${CARCH}${PKGEXT}"
+	local ret=0
 
 	# when fileglobbing, we want * in an empty directory to expand to
 	# the null string rather than itself
 	shopt -s nullglob
+	bsdtar -cf - $comp_files * > "$pkg_file" || ret=$?
+	shopt -u nullglob
 
-	if ! bsdtar -c${TAR_OPT}f "$pkg_file" $comp_files *; then
+	if [ $ret -eq 0 ]; then
+		case "$PKGEXT" in
+			*tar.gz)  gzip -f -n "$pkg_file" ;;
+			*tar.bz2) bzip2 -f "$pkg_file" ;;
+		esac
+		ret=$?
+	fi
+
+	if [ $ret -ne 0 ]; then
 		error "$(gettext "Failed to create package file.")"
 		exit 1 # TODO: error code
 	fi
-	shopt -u nullglob
 }
 
 create_srcpackage() {
diff --git a/scripts/pkgdelta.sh.in b/scripts/pkgdelta.sh.in
new file mode 100644
index 00000000..588dc49d
--- /dev/null
+++ b/scripts/pkgdelta.sh.in
@@ -0,0 +1,165 @@
+#!/bin/bash
+#
+#   pkgdelta - create delta files for use with pacman and repo-add
+#   @configure_input@
+#
+#   Copyright (c) 2009 Xavier Chantry <shiningxc@gmail.com>
+#
+#   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, see <http://www.gnu.org/licenses/>.
+#
+
+# bash options
+set -o nounset
+set -o errexit
+
+# gettext initialization
+export TEXTDOMAIN='pacman'
+export TEXTDOMAINDIR='@localedir@'
+
+myver='@PACKAGE_VERSION@'
+
+QUIET=0
+
+# ensure we have a sane umask set
+umask 0022
+
+msg() {
+	[ $QUIET -ne 0 ] && return
+	local mesg=$1; shift
+	printf "==> ${mesg}\n" "$@" >&1
+}
+
+warning() {
+	local mesg=$1; shift
+	printf "==> $(gettext "WARNING:") ${mesg}\n" "$@" >&2
+}
+
+error() {
+	local mesg=$1; shift
+	printf "==> $(gettext "ERROR:") ${mesg}\n" "$@" >&2
+}
+
+# print usage instructions
+usage() {
+	printf "pkgdelta (pacman) %s\n\n" "$myver"
+	printf "$(gettext "Usage: pkgdelta [-q] <package1> <package2>\n")"
+	printf "$(gettext "\
+	pkgdelta will create a delta file between two packages\n\
+This delta file can then be added to a database using repo-add.\n\n")"
+	echo "$(gettext "Example:  pkgdelta pacman-3.0.0.pkg.tar.gz pacman-3.0.1.pkg.tar.gz")"
+}
+
+version() {
+	printf "pkgdelta (pacman) %s\n\n" "$myver"
+	printf "$(gettext "\
+Copyright (c) 2009 Xavier Chantry <shiningxc@gmail.com>.\n\n\
+This is free software; see the source for copying conditions.\n\
+There is NO WARRANTY, to the extent permitted by law.\n")"
+}
+
+read_pkginfo()
+{
+	pkgname= pkgver= arch=
+	local OLDIFS=$IFS
+	# IFS (field separator) is only the newline character
+	IFS="
+"
+	local line var val
+	for line in $(bsdtar -xOf "$1" .PKGINFO 2>/dev/null |
+		grep -v "^#" | sed 's|\(\w*\)\s*=\s*\(.*\)|\1="\2"|'); do
+		eval "$line"
+		if [ -n "$pkgname" -a -n "$pkgver" -a -n "$arch" ]; then
+			IFS=$OLDIFS
+			return 0
+		fi
+	done
+	IFS=$OLDIFS
+	error "$(gettext "Invalid package '%s'")" "$1"
+	return 1
+}
+
+# $oldfile $oldmd5 $newfile $newmd5 $deltafile $deltamd5 $deltasize
+create_xdelta()
+{
+	local oldfile=$1
+	local newfile=$2
+	local \
+	oldname oldver oldarch \
+	newname newver newarch \
+	deltafile
+
+	read_pkginfo "$oldfile" || return 1
+	oldname="$pkgname"
+	oldver="$pkgver"
+	oldarch="$arch"
+	read_pkginfo "$newfile" || return 1
+	newname="$pkgname"
+	newver="$pkgver"
+	newarch="$arch"
+
+	if [ "$oldname" != "$newname" ]; then
+		error "$(gettext "The package names don't match : '%s' and '%s'")" "$oldname" "$newname"
+		return 1
+	fi
+
+	if [ "$oldarch" != "$newarch" ]; then
+		error "$(gettext "The package architectures don't match : '%s' and '%s'")" "$oldarch" "$newarch"
+		return 1
+	fi
+
+	if [ "$oldver" == "$newver" ]; then
+		error "$(gettext "Both packages have the same version : '%s'")" "$newver"
+		return 1
+	fi
+
+	msg "$(gettext "Generating delta from version %s to version %s")" "$oldver" "$newver"
+	deltafile="$(dirname $newfile)/$pkgname-${oldver}_to_${newver}-$arch.delta"
+	local ret=0
+
+	xdelta3 -q -f -s "$oldfile" "$newfile" "$deltafile" || ret=$?
+	if [ $ret -ne 0 ]; then
+		error "$(gettext "Delta could not be created.")"
+		return 1
+	else
+		msg "$(gettext "Generated delta : '%s'")" "$deltafile"
+		[ $QUIET -eq 1 ] && echo "$deltafile"
+	fi
+	return 0
+}
+
+case "$1" in
+	-q|--quiet) QUIET=1; shift ;;
+esac
+
+if [ $# -ne 2 ]; then
+	usage
+	exit 0
+fi
+
+if [ ! -f "$1" ]; then
+	error "$(gettext "File '%s' does not exist")" "$1"
+	exit 0
+fi
+
+if [ ! -f "$2" ]; then
+	error "$(gettext "File '%s' does not exist")" "$2"
+	exit 0
+fi
+
+if [ ! "$(type -p xdelta3)" ]; then
+	error "$(gettext "Cannot find the xdelta3 binary! Is xdelta3 installed?")"
+	exit 1
+fi
+
+create_xdelta "$1" "$2"
diff --git a/scripts/repo-add.sh.in b/scripts/repo-add.sh.in
index b12188ce..2390a92c 100644
--- a/scripts/repo-add.sh.in
+++ b/scripts/repo-add.sh.in
@@ -28,7 +28,10 @@ myver='@PACKAGE_VERSION@'
 confdir='@sysconfdir@'
 
 QUIET=0
-REPO_DB_FILE=""
+REPO_DB_FILE=
+LOCKFILE=
+CLEAN_LOCK=0
+startdir="$PWD"
 
 # ensure we have a sane umask set
 umask 0022
@@ -57,8 +60,8 @@ error() {
 # print usage instructions
 usage() {
 	printf "repo-add, repo-remove (pacman) %s\n\n" "$myver"
-	printf "$(gettext "Usage: repo-add [-q] <path-to-db> <package> ...\n")"
-	printf "$(gettext "Usage: repo-remove [-q] <path-to-db> <packagename> ...\n\n")"
+	printf "$(gettext "Usage: repo-add [-q] <path-to-db> <package|delta> ...\n")"
+	printf "$(gettext "Usage: repo-remove [-q] <path-to-db> <packagename|delta> ...\n\n")"
 	printf "$(gettext "\
 repo-add will update a package database by reading a package file.\n\
 Multiple packages to add can be specified on the command line.\n\n")"
@@ -93,36 +96,86 @@ write_list_entry() {
 	fi
 }
 
-# write a delta entry to the pacman database
-#   arg1 - path to delta
+find_pkgentry()
+{
+	local pkgname=$1
+	local pkgentry
+	for pkgentry in $tmpdir/$pkgname*; do
+		name=${pkgentry##*/}
+		if [ "${name%-*-*}" = "$pkgname" ]; then
+			echo $pkgentry
+			return 0
+		fi
+	done
+	return 1
+}
+
+# Get the package name from the delta filename
+get_delta_pkgname() {
+	local tmp
+
+	tmp=${1##*/}
+	echo ${tmp%-*-*_to*}
+}
+
+# write a delta entry
+#   arg1 - path to delta file
 db_write_delta()
 {
-	# blank out all variables
-	local deltafile="$1"
-	local filename=$(basename "$deltafile")
-	local deltavars pkgname fromver tover arch csize md5sum
-
-	# format of the delta filename:
-	# (package)-(fromver)_to_(tover)-(arch).delta
-	deltavars=( $(echo "$filename" | sed -e 's/\(.*\)-\(.*-.*\)_to_\(.*-.*\)-\(.*\).delta/\1 \2 \3 \4/') )
-	pkgname=${deltavars[0]}
-	fromver=${deltavars[1]}
-	tover=${deltavars[2]}
-	arch=${deltavars[3]}
-
-	# get md5sum and size of delta
+	deltafile="$1"
+	pkgname="$(get_delta_pkgname $deltafile)"
+
+	pkgentry=$(find_pkgentry $pkgname)
+	if [ -z "$pkgentry" ]; then
+		return 1
+	fi
+	deltas="$pkgentry/deltas"
+	# create deltas file if it does not already exist
+	if [ ! -f "$deltas" ]; then
+		msg2 "$(gettext "Creating 'deltas' db entry...")"
+		echo -e "%DELTAS%" >>$deltas
+	fi
+	# get md5sum and compressed size of package
 	md5sum="$(openssl dgst -md5 "$deltafile" | awk '{print $NF}')"
 	csize=$(@SIZECMD@ "$deltafile")
 
-	# ensure variables were found
-	if [ -z "$pkgname" -o -z "$fromver" -o -z "$tover" -o -z "$arch" ]; then
-		return 1
+	oldfile=$(xdelta3 printhdr $deltafile | grep "XDELTA filename (source)" | sed 's/.*: *//')
+	newfile=$(xdelta3 printhdr $deltafile | grep "XDELTA filename (output)" | sed 's/.*: *//')
+
+	if grep -q "$oldfile.*$newfile" $deltas; then
+		warning "$(gettext "An entry for '%s' already existed")" "$deltafile"
+		sed -i.backup "/$oldfile.*$newfile/d" $deltas && rm -f $deltas.backup
+		msg2 "$(gettext "Removing existing entry '%s'...")" "$deltafile"
 	fi
+	echo ${deltafile##*/} $md5sum $csize $oldfile $newfile >> $deltas
 
-	# add the entry for this delta file
-	echo -e "$fromver $tover $csize $filename $md5sum" >>deltas
+	return 0
 } # end db_write_delta
 
+# remove a delta entry
+#   arg1 - path to delta file
+db_remove_delta()
+{
+	deltafile="$1"
+	filename=${deltafile##*/}
+	pkgname="$(get_delta_pkgname $deltafile)"
+
+	pkgentry=$(find_pkgentry $pkgname)
+	if [ -z "$pkgentry" ]; then
+		return 1
+	fi
+	deltas="$pkgentry/deltas"
+	if [ ! -f "$deltas" ]; then
+		return 1
+	fi
+	if grep -q "$filename" $deltas; then
+		sed -i.backup "/$filename/d" $deltas && rm -f $deltas.backup
+		msg2 "$(gettext "Removing existing entry '%s'...")" "$filename"
+		return 0
+	fi
+
+	return 1
+} # end db_remove_delta
 
 # write an entry to the pacman database
 #   arg1 - path to package
@@ -130,10 +183,8 @@ db_write_entry()
 {
 	# blank out all variables
 	local pkgfile="$1"
-	local pkgname pkgver pkgdesc url builddate packager csize size \
-		group depend backup license replaces provides conflict force \
-		_groups _depends _backups _licenses _replaces _provides _conflicts \
-		startdir optdepend _optdepends md5sum
+	local pkgname pkgver pkgdesc csize size md5sum url arch builddate packager force \
+		_groups _licenses _replaces _depends _conflicts _provides _optdepends
 
 	local OLDIFS="$IFS"
 	# IFS (field separator) is only the newline character
@@ -150,12 +201,11 @@ db_write_entry()
 		declare $var="$val"
 		case "$var" in
 			group)    _groups="$_groups$group\n" ;;
-			depend)   _depends="$_depends$depend\n" ;;
-			backup)   _backups="$_backups$backup\n" ;;
 			license)  _licenses="$_licenses$license\n" ;;
 			replaces) _replaces="$_replaces$replaces\n" ;;
-			provides) _provides="$_provides$provides\n" ;;
+			depend)   _depends="$_depends$depend\n" ;;
 			conflict) _conflicts="$_conflicts$conflict\n" ;;
+			provides) _provides="$_provides$provides\n" ;;
 			optdepend) _optdepends="$_optdepends$optdepend\n" ;;
 		esac
 	done
@@ -172,8 +222,7 @@ db_write_entry()
 		return 1
 	fi
 
-	startdir=$(pwd)
-	pushd "$gstmpdir" 2>&1 >/dev/null
+	cd "$tmpdir"
 
 	if [ -d "$pkgname-$pkgver" ]; then
 		warning "$(gettext "An entry for '%s' already existed")" "$pkgname-$pkgver"
@@ -186,6 +235,9 @@ db_write_entry()
 	mkdir "$pkgname-$pkgver"
 	cd "$pkgname-$pkgver"
 
+	# restore an eventual deltas file
+	[ -f "../$pkgname.deltas" ] && mv "../$pkgname.deltas" deltas
+
 	# create desc entry
 	msg2 "$(gettext "Creating 'desc' db entry...")"
 	echo -e "%FILENAME%\n$(basename "$1")\n" >>desc
@@ -210,45 +262,14 @@ db_write_entry()
 
 	# create depends entry
 	msg2 "$(gettext "Creating 'depends' db entry...")"
+	# create the file even if it will remain empty
+	touch "depends"
 	write_list_entry "DEPENDS" "$_depends" "depends"
 	write_list_entry "CONFLICTS" "$_conflicts" "depends"
 	write_list_entry "PROVIDES" "$_provides" "depends"
 	write_list_entry "OPTDEPENDS" "$_optdepends" "depends"
 
-	# create deltas entry if there are delta files
-	# Xav : why should deltas be in $startdir?
-	for delta in $startdir/$pkgname-*-*_to_*-*-$arch.delta; do
-		# This for loop also pulls in all files that start with the current package
-		# name and are followed by a -whatever. For instance, running this loop for
-		# gcc would also grab gcc-libs. To guard against this, compare the package
-		# name of the delta to the current package name.
-		local filename=$(basename "$delta")
-		local dpkgname="$(echo "$filename" | sed -e 's/\(.*\)-.*-.*_to_.*-.*-.*.delta/\1/')"
-		if [ "$pkgname" = "$dpkgname" -a -f "$delta" ]; then
-			# create deltas file if it does not already exist
-			if [ ! -f "deltas" ]; then
-				msg2 "$(gettext "Creating 'deltas' db entry...")"
-				echo -e "%DELTAS%" >>deltas
-			fi
-
-			# write this delta entry
-			if db_write_delta "$delta"; then
-				msg2 "$(gettext "Added delta '%s'")" "$(basename "$delta")"
-			else
-				warning "$(gettext "Could not add delta '%s'")" "$(basename "$delta")"
-			fi
-		fi
-	done
-	# add the final newline
-	[ -f "deltas" ] && echo -e "" >>deltas
-
-	popd 2>&1 >/dev/null
-
-	# preserve the modification time
-	# Xav : what for?
-	pkgdir="$gstmpdir/$pkgname-$pkgver"
-	touch -r "$pkgfile" "$pkgdir/desc" "$pkgdir/depends"
-	[ -f "$pkgdir/deltas" ] && touch -r "$pkgfile" "$pkgdir/deltas"
+	cd "$startdir"
 
 	return 0
 } # end db_write_entry
@@ -256,20 +277,122 @@ db_write_entry()
 # remove existing entries from the DB
 #   arg1 - package name
 db_remove_entry() {
-	pushd "$gstmpdir" 2>&1 >/dev/null
-
-	# remove any other package in the DB with same name
-	local existing
-	for existing in *; do
-		if [ "${existing%-*-*}" = "$1" ]; then
-			msg2 "$(gettext "Removing existing package '%s'...")" "$existing"
-			rm -rf "$existing"
+	local pkgname=$1
+	local notfound=1
+	local pkgentry=$(find_pkgentry $pkgname)
+	while [ -n "$pkgentry" ]; do
+		notfound=0
+		if [ -f "$pkgentry/deltas" ]; then
+			mv "$pkgentry/deltas" "$tmpdir/$pkgname.deltas"
 		fi
+		msg2 "$(gettext "Removing existing entry '%s'...")" \
+		"$(basename $pkgentry)"
+		rm -rf $pkgentry
+		pkgentry=$(find_pkgentry $pkgname)
 	done
-
-	popd 2>&1 >/dev/null
+	return $notfound
 } # end db_remove_entry
 
+check_repo_db()
+{
+	# check lock file
+	if ( set -o noclobber; echo "$$" > "$LOCKFILE") 2> /dev/null; then
+		CLEAN_LOCK=1
+	else
+		error "$(gettext "Failed to acquire lockfile: %s.")" "$LOCKFILE"
+		[ -f "$LOCKFILE" ] && error "$(gettext "Held by %s")" "$(cat $LOCKFILE)"
+		exit 1
+	fi
+
+	if [ -f "$REPO_DB_FILE" ]; then
+		if ! (bsdtar -tf "$REPO_DB_FILE" | grep -q "/desc"); then
+			error "$(gettext "Repository file '%s' is not a proper pacman database.")" "$REPO_DB_FILE"
+			exit 1
+		fi
+		msg "$(gettext "Extracting database to a temporary location...")"
+		bsdtar -xf "$REPO_DB_FILE" -C "$tmpdir"
+	else
+		if [ "$cmd" == "repo-remove" ]; then
+			error "$(gettext "Repository file '%s' was not found.")" "$REPO_DB_FILE"
+			exit 1
+		fi
+	fi
+}
+
+add()
+{
+	if [ ! -f "$1" ]; then
+		error "$(gettext "File '%s' not found.")" "$1"
+		return 1
+	fi
+
+	if [ "${1##*.}" == "delta" ]; then
+		deltafile=$1
+		msg "$(gettext "Adding delta '%s'")" "$deltafile"
+		if [ ! "$(type -p xdelta3)" ]; then
+			error "$(gettext "Cannot find the xdelta3 binary! Is xdelta3 installed?")"
+			exit 1
+		fi
+		if db_write_delta "$deltafile"; then
+			return 0
+		else
+			return 1
+		fi
+	fi
+
+	pkgfile=$1
+	if ! bsdtar -tf "$pkgfile" .PKGINFO 2>&1 >/dev/null; then
+		error "$(gettext "'%s' is not a package file, skipping")" "$pkgfile"
+		return 1
+	fi
+
+	msg "$(gettext "Adding package '%s'")" "$pkgfile"
+
+	db_write_entry "$pkgfile"
+}
+
+remove()
+{
+	if [ "${1##*.}" == "delta" ]; then
+		deltafile=$1
+		msg "$(gettext "Searching for delta '%s'...")" "$deltafile"
+		if db_remove_delta "$deltafile"; then
+			return 0
+		else
+			error "$(gettext "Delta matching '%s' not found.")" "$deltafile"
+			return 1
+		fi
+	fi
+
+	pkgname=$1
+	msg "$(gettext "Searching for package '%s'...")" "$pkgname"
+
+	if db_remove_entry "$pkgname"; then
+		rm -f "$tmpdir/$pkgname.deltas"
+		return 0
+	else
+		error "$(gettext "Package matching '%s' not found.")" "$pkgname"
+		return 1
+	fi
+}
+
+trap_exit()
+{
+	echo
+	error "$@"
+	exit 1
+}
+
+clean_up() {
+	local exit_code=$?
+
+	cd "$startdir"
+	[ -d "$tmpdir" ] && rm -rf "$tmpdir"
+	[ $CLEAN_LOCK -eq 1 -a -f "$LOCKFILE" ] && rm -f "$LOCKFILE"
+
+	exit $exit_code
+}
+
 # PROGRAM START
 
 # determine whether we have gettext; make it a no-op if we do not
@@ -279,17 +402,10 @@ if [ ! $(type -t gettext) ]; then
 	}
 fi
 
-# check for help flags
-if [ "$1" = "-h" -o "$1" = "--help" ]; then
-	usage
-	exit 0
-fi
-
-# check for version flags
-if [ "$1" = "-V" -o "$1" = "--version" ]; then
-	version
-	exit 0
-fi
+case "$1" in
+	-h|--help) usage; exit 0;;
+	-V|--version) version; exit 0;;
+esac
 
 # check for correct number of args
 if [ $# -lt 2 ]; then
@@ -297,11 +413,6 @@ if [ $# -lt 2 ]; then
 	exit 1
 fi
 
-# main routine
-gstmpdir=$(mktemp -d /tmp/repo-tools.XXXXXXXXXX) || (\
-	error "$(gettext "Cannot create temp directory for database building.")"; \
-	exit 1)
-
 # figure out what program we are
 cmd="$(basename $0)"
 if [ "$cmd" != "repo-add" -a "$cmd" != "repo-remove" ]; then
@@ -309,55 +420,42 @@ if [ "$cmd" != "repo-add" -a "$cmd" != "repo-remove" ]; then
 	exit 1
 fi
 
+tmpdir=$(mktemp -d /tmp/repo-tools.XXXXXXXXXX) || (\
+	error "$(gettext "Cannot create temp directory for database building.")"; \
+	exit 1)
+
+trap 'clean_up' EXIT
+trap 'trap_exit "$(gettext "TERM signal caught. Exiting...")"' TERM HUP QUIT
+trap 'trap_exit "$(gettext "Aborted by user! Exiting...")"' INT
+trap 'trap_exit "$(gettext "An unknown error has occured. Exiting...")"' ERR
+
 success=0
 # parse arguments
 for arg in "$@"; do
-	if [ "$arg" == "--force" -o "$arg" == "-f" ]; then
-		warning "$(gettext "the -f and --force options are no longer recognized")"
-		msg2 "$(gettext "use options=(force) in the PKGBUILD instead")"
-	elif [ "$arg" == "--quiet" -o "$arg" == "-q" ]; then
-		QUIET=1
-	elif [ -z "$REPO_DB_FILE" ]; then
-		REPO_DB_FILE="$arg"
-		if [ -f "$REPO_DB_FILE" ]; then
-			if ! (bsdtar -tf "$REPO_DB_FILE" | grep -q "/desc"); then
-				error "$(gettext "Repository file '%s' is not a proper pacman database.")" "$REPO_DB_FILE"
-				exit 1
-			fi
-			msg "$(gettext "Extracting database to a temporary location...")"
-			bsdtar -xf "$REPO_DB_FILE" -C "$gstmpdir"
-		elif [ "$cmd" == "repo-remove" ]; then
-			error "$(gettext "Repository file '%s' was not found.")" "$REPO_DB_FILE"
-			exit 1
-		fi
-	else
-		if [ "$cmd" == "repo-add" ]; then
-			if [ -f "$arg" ]; then
-				if ! bsdtar -tf "$arg" .PKGINFO 2>&1 >/dev/null; then
-					error "$(gettext "'%s' is not a package file, skipping")" "$arg"
-				else
-					msg "$(gettext "Adding package '%s'")" "$arg"
-
-					if db_write_entry "$arg"; then
-						success=1
-					fi
-				fi
+	case "$arg" in
+		-q|--quiet) QUIET=1;;
+
+		-f|--force)
+			warning "$(gettext "the -f and --force options are no longer recognized")"
+			msg2 "$(gettext "use options=(force) in the PKGBUILD instead")"
+			;;
+
+		*)
+			if [ -z "$REPO_DB_FILE" ]; then
+				REPO_DB_FILE="$arg"
+				LOCKFILE="$REPO_DB_FILE.lck"
+				check_repo_db
 			else
-				error "$(gettext "Package '%s' not found.")" "$arg"
+				case "$cmd" in
+					repo-add) add $arg && success=1 ;;
+					repo-remove) remove $arg && success=1 ;;
+				esac
 			fi
-		elif [ "$cmd" == "repo-remove" ]; then
-			msg "$(gettext "Searching for package '%s'...")" "$arg"
-
-			if db_remove_entry "$arg"; then
-				success=1
-			else
-				error "$(gettext "Package matching '%s' not found.")" "$arg"
-			fi
-		fi
-	fi
+			;;
+	esac
 done
 
-# if all operations were a success, re-zip database
+# if at least one operation was a success, re-zip database
 if [ $success -eq 1 ]; then
 	msg "$(gettext "Creating updated database file '%s'")" "$REPO_DB_FILE"
 
@@ -370,22 +468,20 @@ if [ $success -eq 1 ]; then
 
 	filename=$(basename "$REPO_DB_FILE")
 
-	pushd "$gstmpdir" 2>&1 >/dev/null
+	cd "$tmpdir"
 	if [ -n "$(ls)" ]; then
 		bsdtar -c${TAR_OPT}f "$filename" *
 	else
 		# the database will be moved to .old below, and there will be no new one to replace it
 		error "$(gettext "All packages have been removed from the database. Deleting '%s'.")" "$REPO_DB_FILE"
 	fi
-	popd 2>&1 >/dev/null
+	cd "$startdir"
 
 	[ -f "$REPO_DB_FILE" ] && mv -f "$REPO_DB_FILE" "${REPO_DB_FILE}.old"
-	[ -f "$gstmpdir/$filename" ] && mv "$gstmpdir/$filename" "$REPO_DB_FILE"
+	[ -f "$tmpdir/$filename" ] && mv "$tmpdir/$filename" "$REPO_DB_FILE"
 else
 	msg "$(gettext "No packages modified, nothing to do.")"
 fi
 
-# remove the temp directory used to unzip
-[ -d "$gstmpdir" ] && rm -rf "$gstmpdir"
-
+exit 0
 # vim: set ts=2 sw=2 noet: