From 1b3edb9db50fc047f10f2b082becbc3de6863727 Mon Sep 17 00:00:00 2001
From: Florian Pritz <bluewind@xinu.at>
Date: Sun, 19 Feb 2017 19:47:17 +0100
Subject: borg-restore.pl: Add config file

Signed-off-by: Florian Pritz <bluewind@xinu.at>
---
 borg-restore.pl | 88 +++++++++++++++++++++++++++++++++++++++++++++++++++------
 1 file changed, 80 insertions(+), 8 deletions(-)

diff --git a/borg-restore.pl b/borg-restore.pl
index 5a0a139..2735a77 100755
--- a/borg-restore.pl
+++ b/borg-restore.pl
@@ -55,6 +55,60 @@ s (seconds), min (minutes), h (hours), d (days), m (months = 31 days), y (year).
 
 =back
 
+=head1 CONFIGURATION
+
+borg-restore.pl searches for configuration files in the following locations in
+order. The first file found will be used, any later ones are ignored. If no
+files are found, defaults are used.
+
+=over
+
+=item * $XDG_CONFIG_HOME/borg-restore.cfg
+
+=item * /etc/borg-restore.cfg
+
+=back
+
+=head2 Configuration Options
+
+You can set the following options in the config file.
+
+Note that the configuration file is parsed as a perl script. Thus you can also
+use any features available in perl itself.
+
+=over
+
+=item C<$cache_path_base>
+
+This defaults to "C<$XDG_CACHE_HOME>/borg-restore.pl". It contains the lookup database.
+
+=item C<@backup_prefixes>
+
+This is an array of prefixes that need to be added when looking up a file in the
+backup archives. If you use filesystem snapshots and the snapshot for /home is
+located at /mnt/snapshots/home, you have to add the following:
+
+# In the backup archives, /home has the path /mnt/snapshots/home
+{regex => "^/home/", replacement => "mnt/snapshots/home/"},
+
+The regex must always include the leading slash and it is suggested to include
+a tailing slash as well to prevent clashes with directories that start with the
+same string. The first regex that matches for a given file is used. This
+setting only affects lookups, it does not affect the creation of the database
+with --update-database.
+
+=back
+
+=head2 Example Configuration
+
+ $cache_path_base = "/mnt/somewhere/borg-restore.pl-cache";
+ @backup_prefixes = (
+ 	{regex => "^/home/", replacement => "mnt/snapshots/home/"},
+ 	# /boot is not snapshotted
+ 	{regex => "^/boot", replacement => ""},
+ 	{regex => "^/", replacement => "mnt/snapshots/root/"},
+ );
+
 =head1 SYNOPSIS
 
 borg-restore.pl [options] <path>
@@ -76,6 +130,30 @@ borg-restore.pl [options] <path>
 
 use v5.10;
 
+{
+package Settings;
+	our $cache_path_base = sprintf("%s/borg-restore.pl", $ENV{XDG_CACHE_HOME} // $ENV{HOME}."/.cache");
+	our @backup_prefixes = (
+		{regex => "^/", replacement => ""},
+	);
+
+	my @configfiles = (
+		sprintf("%s/borg-restore.cfg", $ENV{XDG_CONFIG_HOME} // $ENV{HOME}."/.config"),
+		"/etc/borg-restore.cfg",
+	);
+
+	for my $configfile (@configfiles) {
+		if (-e $configfile) {
+			unless (my $return = do $configfile) {
+				die "couldn't parse $configfile: $@" if $@;
+				die "couldn't do $configfile: $!"    unless defined $return;
+				die "couldn't run $configfile"       unless $return;
+			}
+		}
+	}
+	$cache_path_base = Helper::untaint($cache_path_base, qr/.*/);
+}
+
 package main;
 
 use autodie;
@@ -95,12 +173,6 @@ use Time::HiRes;
 
 my %opts;
 my %db;
-my $cache_path_base = "/home/flo/.cache/borg-restore.pl";
-my @backup_prefixes = (
-	{regex => "^/home/", replacement => "mnt/snapshots/vg0-homeborg/"},
-	{regex => "^/boot/", replacement => ""},
-	{regex => "^/", replacement => "mnt/snapshots/vg0-rootborg/"},
-);
 
 sub debug {
 	say STDERR @_ if $opts{debug};
@@ -268,7 +340,7 @@ sub restore {
 }
 
 sub get_cache_dir {
-	return "$cache_path_base/v2";
+	return "$Settings::cache_path_base/v2";
 }
 
 sub get_cache_path {
@@ -534,7 +606,7 @@ sub main {
 		$destination = dirname($abs_path);
 	}
 	my $backup_path = $abs_path;
-	for my $backup_prefix (@backup_prefixes) {
+	for my $backup_prefix (@Settings::backup_prefixes) {
 		if ($backup_path =~ m/$backup_prefix->{regex}/) {
 			$backup_path =~ s/$backup_prefix->{regex}/$backup_prefix->{replacement}/;
 			last;
-- 
cgit v1.2.3-24-g4f1b