From c0ac82be6a91cd4f5e43e7de6281d2854bbf63c2 Mon Sep 17 00:00:00 2001
From: Eugene Burkov <e.burkov@adguard.com>
Date: Tue, 24 May 2022 14:43:54 +0300
Subject: [PATCH] Pull request: 4480 fix sysv service script

Merge in DNS/adguard-home from 4480-sysv-boot to master

Updates #4480.

Squashed commit of the following:

commit c9645b1f3bd22a249c666e4485818bab6769f32d
Author: Eugene Burkov <E.Burkov@AdGuard.COM>
Date:   Tue May 24 14:25:09 2022 +0300

    home: imp sysv script

commit cc323364ba6cce0284cbc6be9133a50a51b71f56
Author: Eugene Burkov <E.Burkov@AdGuard.COM>
Date:   Mon May 23 21:13:06 2022 +0300

    home: fix sysv service script
---
 CHANGELOG.md             | 2 ++
 internal/home/service.go | 9 ++++++---
 2 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 8aca8f15..9d837c95 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -128,6 +128,7 @@ In this release, the schema version has changed from 12 to 14.
 
 ### Fixed
 
+- Service startup on boot on systems using SysV-init ([#4480]).
 - Detection of the stopped service status on macOS and Linux ([#4273]).
 - Case-sensitive ClientID ([#4542]).
 - Slow version update queries making other HTTP APIs unresponsible ([#4499]).
@@ -150,6 +151,7 @@ In this release, the schema version has changed from 12 to 14.
 [#4238]: https://github.com/AdguardTeam/AdGuardHome/issues/4238
 [#4273]: https://github.com/AdguardTeam/AdGuardHome/issues/4273
 [#4276]: https://github.com/AdguardTeam/AdGuardHome/issues/4276
+[#4480]: https://github.com/AdguardTeam/AdGuardHome/issues/4480
 [#4499]: https://github.com/AdguardTeam/AdGuardHome/issues/4499
 [#4503]: https://github.com/AdguardTeam/AdGuardHome/issues/4503
 [#4533]: https://github.com/AdguardTeam/AdGuardHome/issues/4533
diff --git a/internal/home/service.go b/internal/home/service.go
index 70ab3c78..831a80d0 100644
--- a/internal/home/service.go
+++ b/internal/home/service.go
@@ -433,8 +433,11 @@ EnvironmentFile=-/etc/sysconfig/{{.Name}}
 WantedBy=multi-user.target
 `
 
-// Note: we should keep it in sync with the template from service_sysv_linux.go file
-// Use "ps | grep -v grep | grep $(get_pid)" because "ps PID" may not work on OpenWrt
+// sysvScript is the source of the daemon script for SysV-based Linux systems.
+// Keep as close as possible to the https://github.com/kardianos/service/blob/29f8c79c511bc18422bb99992779f96e6bc33921/service_sysv_linux.go#L187.
+//
+// Use ps command instead of reading the procfs since it's a more
+// implementation-independent approach.
 const sysvScript = `#!/bin/sh
 # For RedHat and cousins:
 # chkconfig: - 99 01
@@ -465,7 +468,7 @@ get_pid() {
 }
 
 is_running() {
-    [ -f "$pid_file" ] && ps | grep -v grep | grep $(get_pid) > /dev/null 2>&1
+    [ -f "$pid_file" ] && ps -p "$(get_pid)" > /dev/null 2>&1
 }
 
 case "$1" in