Bug#797724: debian-installer: Use apt-config's shell command to get sourcelist/sourceparts

[James McCoy]

Package: debian-installer
Version: 20150828
Severity: normal
Tags: patch

Instead of caching apt-config's output and piping through sed, it seems
simpler to use apt-config's support for providing the information for
evaluation by the shell.  The ‘/f’ modifier on the end of the config
name makes apt-config provide the full path as a filename (i.e., no
trailing slash).

-- System Information:
Debian Release: stretch/sid
  APT prefers unstable
  APT policy: (500, 'unstable'), (1, 'experimental')
Architecture: amd64 (x86_64)
Foreign Architectures: i386

Kernel: Linux 4.1.0-2-amd64 (SMP w/4 CPU cores)
Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)

>From e6835a537c27c5815e361eb58fd88bb233d5582e Mon Sep 17 00:00:00 2001
From: James McCoy <james...@debian.org>
Date: Tue, 1 Sep 2015 20:13:10 -0400
Subject: [PATCH] Use apt-config's shell command to get sourcelist/sourceparts

Signed-off-by: James McCoy <james...@debian.org>
---
 build/util/gen-sources.list.udeb | 12 +++---------
 1 file changed, 3 insertions(+), 9 deletions(-)

diff --git a/build/util/gen-sources.list.udeb b/build/util/gen-sources.list.udeb
index 26a0ac2..715dc68 100755
--- a/build/util/gen-sources.list.udeb
+++ b/build/util/gen-sources.list.udeb
@@ -45,20 +45,14 @@ get_mirrors() {
 	done
 }
 
-# Cache the apt configuration dump, with only the needed namespace
-APT_CONFIG=$(apt-config dump | grep '^Dir::Etc')
-
-# Get the system apt directory
-APT_DIR_ETC=$(echo "$APT_CONFIG" | sed -n -e 's/^Dir::Etc *\"\(.*\)\";$/\1/p')
-
 # Fetch APT's sources.list
-APT_SOURCELIST=$(echo "$APT_CONFIG" | sed -n -e 's/^Dir::Etc::sourcelist *\"\(.*\)\";$/\1/p')
+eval $(apt-config shell APT_SOURCELIST Dir::Etc::sourcelist/f)
 
 # Fetch APT' sources.list.d
-APT_SOURCEPARTS=$(echo "$APT_CONFIG" | sed -n -e 's/^Dir::Etc::sourceparts *\"\(.*\)\";$/\1/p')
+eval $(apt-config shell APT_SOURCEPARTS Dir::Etc::sourceparts/f)
 
 # Also use mirrors defined in files in $SOURCES_LIST.d/
-MIRRORS="$(get_mirrors $SOURCES_LIST /$APT_DIR_ETC/$APT_SOURCELIST /$APT_DIR_ETC/$APT_SOURCEPARTS/*)"
+MIRRORS="$(get_mirrors $SOURCES_LIST $APT_SOURCELIST $APT_SOURCEPARTS/*)"
 
 if ! which 'wget' >/dev/null; then
 	echo "ERROR: the command wget is not available; please install it" >&2
-- 
2.5.1