From 30b22d49d2d0049c82ed615c75fc5bffac476160 Mon Sep 17 00:00:00 2001
From: Axel Burri <axel@tty0.ch>
Date: Sun, 26 Mar 2023 13:19:11 +0200
Subject: [PATCH] btrbk: add vinfo_realpath

---
 btrbk | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/btrbk b/btrbk
index 41bb72e..f345eac 100755
--- a/btrbk
+++ b/btrbk
@@ -355,7 +355,7 @@ my %raw_url_cache;   # map URL to (fake) btr_tree node
 my %mountinfo_cache; # map MACHINE_ID to mount points (sorted descending by file length)
 my %mount_source_cache; # map URL_PREFIX:mount_source (aka device) to btr_tree node
 my %uuid_cache;      # map UUID to btr_tree node
-my %realpath_cache;  # map URL to realpath (symlink target). empty string denotes an error.
+my %realpath_cache;  # map URL to realpath (symlink target). undef denotes an error.
 
 my $tree_inject_id   = 0;  # fake subvolume id for injected nodes (negative)
 my $fake_uuid_prefix = 'XXXXXXXX-XXXX-XXXX-XXXX-'; # plus 0-padded inject_id: XXXXXXXX-XXXX-XXXX-XXXX-000000000000
@@ -2900,6 +2900,15 @@ sub mountinfo_tree($)
 }
 
 
+sub vinfo_realpath($@)
+{
+  my $vol = shift // die;
+  my $url = $vol->{URL} // die;
+  return $realpath_cache{$url} if(exists($realpath_cache{$url}));
+  return $realpath_cache{$url} = system_realpath($vol);
+}
+
+
 sub vinfo_mountpoint
 {
   my $vol = shift // die;