From 05f1ad25b8effdf7497ccc4f3d95cb15a035f0b8 Mon Sep 17 00:00:00 2001
From: Davin McCall <davmac@davmac.org>
Date: Mon, 26 Jun 2017 18:58:03 +0100
Subject: [PATCH] service: use recorded state to check whether we can track
 child process

We have a flag which records whether we are tracking the child process.
A BGPROCESS service can't always track the child, so it stops once the
dependencies have stopped without waiting for the process. Previously we
did a manual check rather than using the existing flag to see whether
the process could be tracked before immediately stopping.
---
 src/service.cc | 16 +++-------------
 src/service.h  |  6 +++---
 2 files changed, 6 insertions(+), 16 deletions(-)

diff --git a/src/service.cc b/src/service.cc
index b6d726a..cda831e 100644
--- a/src/service.cc
+++ b/src/service.cc
@@ -1185,19 +1185,8 @@ void base_process_service::all_deps_stopped() noexcept
         // In most cases, the rest is done in handle_exit_status.
         // If we are a BGPROCESS and the process is not our immediate child, however, that
         // won't work - check for this now:
-        if (record_type == service_type::BGPROCESS) {
-            // TODO use 'tracking_child' instead
-            int status;
-            pid_t r = waitpid(pid, &status, WNOHANG);
-            if (r == -1 && errno == ECHILD) {
-                // We can't track this child (or it's terminated already)
-                stopped();
-            }
-            else if (r == pid) {
-                // Process may have died due to signal since we explicitly requested it to
-                // stop by signalling it; no need to log any termination status.
-                stopped();
-            }
+        if (record_type == service_type::BGPROCESS && ! tracking_child) {
+            stopped();
         }
     }
     else {
@@ -1279,6 +1268,7 @@ base_process_service::base_process_service(service_set *sset, string name, servi
 
     waiting_restart_timer = false;
     reserved_child_watch = false;
+    tracking_child = false;
 }
 
 void base_process_service::do_restart() noexcept
diff --git a/src/service.h b/src/service.h
index c0d1abc..c4640fb 100644
--- a/src/service.h
+++ b/src/service.h
@@ -612,11 +612,11 @@ class base_process_service : public service_record
     service_child_watcher child_listener;
     exec_status_pipe_watcher child_status_listener;
     process_restart_timer restart_timer;
-    timespec last_start_time;
+    time_val last_start_time;
 
     // Restart interval time and restart count are used to track the number of automatic restarts
     // over an interval. Too many restarts over an interval will inhibit further restarts.
-    timespec restart_interval_time;
+    time_val restart_interval_time;
     int restart_interval_count;
 
     timespec restart_interval;
@@ -625,6 +625,7 @@ class base_process_service : public service_record
 
     bool waiting_restart_timer : 1;
     bool reserved_child_watch : 1;
+    bool tracking_child : 1;
 
     // Start the process, return true on success
     virtual bool start_ps_process() noexcept override;
@@ -691,7 +692,6 @@ class bgproc_service : public base_process_service
 
     bool doing_recovery : 1;    // if we are currently recovering a BGPROCESS (restarting process, while
                                 //   holding STARTED service state)
-    bool tracking_child : 1;
 
     enum class pid_result_t {
         OK,
-- 
2.25.1