From 77722599c0ca66b20adfdcffe58b612353ab2def Mon Sep 17 00:00:00 2001
From: John Bachir <j@jjb.cc>
Date: Sat, 11 Sep 2021 01:31:34 +0100
Subject: [PATCH 1/3] coexist with other signal handlers

---
 lib/sidekiq/cli.rb | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/lib/sidekiq/cli.rb b/lib/sidekiq/cli.rb
index df6339a67..cd66459f5 100644
--- a/lib/sidekiq/cli.rb
+++ b/lib/sidekiq/cli.rb
@@ -46,7 +46,10 @@ def run(boot_app: true)
       # USR1 and USR2 don't work on the JVM
       sigs << "USR2" if Sidekiq.pro? && !jruby?
       sigs.each do |sig|
-        trap sig do
+        old_handler = Signal.trap(sig) do
+          if old_handler.respond_to?(:call)
+            old_handler.call
+          end
           self_write.puts(sig)
         end
       rescue ArgumentError

From f6245d3b2bc733d10970c293cf97364928e58da0 Mon Sep 17 00:00:00 2001
From: John Bachir <j@jjb.cc>
Date: Mon, 13 Sep 2021 00:02:10 +0100
Subject: [PATCH 2/3] don't allow error from old handler to disrupt sidekiq
 signal handling

---
 lib/sidekiq/cli.rb | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/lib/sidekiq/cli.rb b/lib/sidekiq/cli.rb
index cd66459f5..8398759df 100644
--- a/lib/sidekiq/cli.rb
+++ b/lib/sidekiq/cli.rb
@@ -48,7 +48,11 @@ def run(boot_app: true)
       sigs.each do |sig|
         old_handler = Signal.trap(sig) do
           if old_handler.respond_to?(:call)
-            old_handler.call
+            begin
+              old_handler.call
+            rescue Exception
+              puts $!.inspect
+            end
           end
           self_write.puts(sig)
         end

From d2ad0fe73128d686092e7baf81bf7beaa4ac2dae Mon Sep 17 00:00:00 2001
From: John Bachir <j@jjb.cc>
Date: Mon, 13 Sep 2021 00:30:18 +0100
Subject: [PATCH 3/3] changelog

---
 Changes.md | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/Changes.md b/Changes.md
index 3aa6dbc2f..e5b66acea 100644
--- a/Changes.md
+++ b/Changes.md
@@ -22,6 +22,8 @@ require "sidekiq/middleware/current_attributes"
 Sidekiq::CurrentAttributes.persist(Myapp::Current) # Your AS:CurrentAttributes singleton
 ```
 - Retry Redis operation if we get an `UNBLOCKED` Redis error. [#4985]
+- **BREAKING CHANGE** Run existing signal-handling code, if there is any, before running sidekiq's
+  signal-handling code. [#4991]
 
 6.2.2
 ---------