From 210a1172ff8d80c20af5bed9bd1536051016d82a Mon Sep 17 00:00:00 2001
From: Adam Warner <me@adamwarner.co.uk>
Date: Sun, 6 Oct 2024 22:39:04 +0100
Subject: [PATCH] Always terminate the container if pihole-FTL binary exits.
 Either naturally or via an error. Don't attempt to restart it, allow the
 container's restart policy to do this.

Signed-off-by: Adam Warner <me@adamwarner.co.uk>
---
 src/bash_functions.sh | 16 +++++------
 src/start.sh          | 65 ++++++++++++++++++++++++++++++++-----------
 2 files changed, 56 insertions(+), 25 deletions(-)

diff --git a/src/bash_functions.sh b/src/bash_functions.sh
index b5f8671f..5a605cdf 100644
--- a/src/bash_functions.sh
+++ b/src/bash_functions.sh
@@ -202,25 +202,25 @@ setup_web_password() {
 start_ftl() {
 
     echo "  [i] pihole-FTL pre-start checks"
-    echo ""
 
     # Remove possible leftovers from previous pihole-FTL processes
     rm -f /dev/shm/FTL-* 2>/dev/null
     rm -f /run/pihole/FTL.sock
 
-    # Is /var/run/pihole used anymore? Or is this just a hangover from old container version
-    # /var/log sorted by running pihole-FTL-prestart.sh
-    # mkdir -p /var/run/pihole /var/log/pihole
-    # touch /var/log/pihole/FTL.log /var/log/pihole/pihole.log
-    # chown -R pihole:pihole /var/run/pihole /var/log/pihole /etc/pihole
-
     fix_capabilities
     sh /opt/pihole/pihole-FTL-prestart.sh
 
     echo "  [i] Starting pihole-FTL ($FTL_CMD) as ${DNSMASQ_USER}"
-    capsh --user=$DNSMASQ_USER --keep=1 -- -c "/usr/bin/pihole-FTL $FTL_CMD >/dev/null" &
     echo ""
 
+    capsh --user=$DNSMASQ_USER --keep=1 -- -c "/usr/bin/pihole-FTL $FTL_CMD >/dev/null"
+    ftl_exit_code=$?
+    # Store the exit code so that we can exit the container with the same code from start.sh
+    echo $ftl_exit_code >/pihole-FTL.exit
+
+    # pihole-FTL has exited, so we should stop the rest of the container
+    killall --signal 15 start.sh
+
     # Notes on above:
     # - DNSMASQ_USER default of pihole is in Dockerfile & can be overwritten by runtime container env
     # - /var/log/pihole/pihole*.log has FTL's output that no-daemon would normally print in FG too
diff --git a/src/start.sh b/src/start.sh
index 4f7b8f37..9b8c58f5 100644
--- a/src/start.sh
+++ b/src/start.sh
@@ -1,4 +1,4 @@
-#!/bin/bash -e
+#!/bin/bash
 
 if [ "${PH_VERBOSE:-0}" -gt 0 ]; then
   set -x
@@ -53,11 +53,13 @@ start() {
   #migrate Gravity Database if needed:
   migrate_gravity
 
-  # Start pihole-FTL
-  start_ftl
+  # Start pihole-FTL in the background
+  start_ftl &
 
-  # Give FTL a couple of seconds to start up
-  sleep 2
+  # Wait until the log file exists before continuing
+  while [ ! -f /var/log/pihole/FTL.log ]; do
+    sleep 0.5
+  done
 
   # If we are migrating from v5 to v6, we now need to run the basic configuration step that we deferred earlier
   # This is because pihole-FTL needs to migrate the config files before we can perform the basic configuration checks
@@ -75,8 +77,8 @@ start() {
     # Start tailing the FTL log from the most recent "FTL Started" message
     # Get the line number
     startFrom=$(grep -n '########## FTL started' /var/log/pihole/FTL.log | tail -1 | cut -d: -f1)
-    # Start the tail from the line number
-    tail -f -n +${startFrom} /var/log/pihole/FTL.log &
+    # Start the tail from the line number and background it
+    tail --follow=name -n +${startFrom} /var/log/pihole/FTL.log &
   else
     echo "  [i] FTL log output is disabled. Remove the Environment variable TAIL_FTL_LOG, or set it to 1 to enable FTL log output."
   fi
@@ -86,22 +88,51 @@ start() {
 }
 
 stop() {
-  # Ensure pihole-FTL shuts down cleanly on SIGTERM/SIGINT
-  ftl_pid=$(pgrep pihole-FTL)
-  killall --signal 15 pihole-FTL
 
-  # Wait for pihole-FTL to exit
-  while test -d /proc/"${ftl_pid}"; do
-    sleep 0.5
-  done
+  # Only attempt to close pihole-FTL if it is running, it may already have crashed
+  if pgrep pihole-FTL >/dev/null; then
+    echo ""
+    echo "  [i] Container stop requested..."
+    echo "  [i] pihole-FTL is running - Attempting to shut it down cleanly"
+    echo ""
+    # Ensure pihole-FTL shuts down cleanly on SIGTERM/SIGINT
+    ftl_pid=$(pgrep pihole-FTL)
+
+    killall --signal 15 pihole-FTL
+
+    # Wait for pihole-FTL to exit
+    while test -d /proc/"${ftl_pid}"; do
+      sleep 0.5
+    done
+  fi
 
-  # If we are running pytest, keep the container alive for a little longer
-  # to allow the tests to complete
+  # Wait for a few seconds to allow the FTL log tail to catch up before exiting the container
+  sleep 2  
+
+  # read the FTL exit code from the file created in the `start_ftl` function
+  FTL_EXIT_CODE=$(cat /pihole-FTL.exit)
+  rm /pihole-FTL.exit
+
+  # ensure the exit code is an integer, if not set it to 1
+  if ! [[ "${FTL_EXIT_CODE}" =~ ^[0-9]+$ ]]; then
+    FTL_EXIT_CODE=1
+  fi
+
+  echo ""
+  echo "  [i] pihole-FTL exited with status $FTL_EXIT_CODE"
+  echo ""
+  echo "  [i] Container will now stop or restart depending on your restart policy"
+  echo "      https://docs.docker.com/engine/containers/start-containers-automatically/#use-a-restart-policy"
+  echo ""
+
+  # # If we are running pytest, keep the container alive for a little longer
+  # # to allow the tests to complete
   if [[ ${PYTEST} ]]; then
     sleep 10
   fi
 
-  exit
+  exit ${FTL_EXIT_CODE}
+
 }
 
 start