From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Christian Glombek <lorbus@fedoraproject.org>
Date: Mon, 8 Oct 2018 11:57:04 +0200
Subject: [PATCH] Add comments and revert logic changes in 01_fallback_counting

---
 util/grub.d/01_fallback_counting.in | 27 +++++++++++++++------------
 1 file changed, 15 insertions(+), 12 deletions(-)

diff --git a/util/grub.d/01_fallback_counting.in b/util/grub.d/01_fallback_counting.in
index 1a0b5fbecfc..be0e770ea82 100644
--- a/util/grub.d/01_fallback_counting.in
+++ b/util/grub.d/01_fallback_counting.in
@@ -1,19 +1,22 @@
 #! /bin/sh -e
 
-if ! systemctl -q is-enabled greenboot.service >/dev/null 2>&1 ; then
-  exit 0
-fi
-
 # Boot Counting
+# The boot_counter env var can be used to count down boot attempts after an
+# OSTree upgrade and choose the rollback deployment when 0 is reached.  Both
+# boot_counter and boot_success need to be (re-)set from userspace.
 cat << EOF
 insmod increment
-if [ -z "\${boot_counter}" ]; then
-  set boot_counter=0
-elif [ "\${boot_counter}" = "0" -o "\${boot_counter}" = "-1" ]; then
-  increment default
-  set boot_counter=-1
-else
-  decrement boot_counter
+# Check if boot_counter exists and boot_success=0 to activate this behaviour.
+if [ -n "\${boot_counter}" -a "\${boot_success}" = "0" ]; then
+  # if countdown has ended, choose to boot rollback deployment (default=1 on
+  # OSTree-based systems)
+  if  [ "\${boot_counter}" = "0" -o "\${boot_counter}" = "-1" ]; then
+    set default=1
+    set boot_counter=-1
+  # otherwise decrement boot_counter
+  else
+    decrement boot_counter
+  fi
+  save_env boot_counter
 fi
-save_env boot_counter
 EOF