From 29d5458ca8b98c70d51b3358845c4eb0813a9f99 Mon Sep 17 00:00:00 2001
From: Daijiro Fukuda <fukuda@clear-code.com>
Date: Fri, 18 Mar 2022 16:50:00 +0900
Subject: [PATCH 01/15] Just refactored codes

Signed-off-by: Daijiro Fukuda <fukuda@clear-code.com>
---
 lib/fluent/supervisor.rb | 40 +++++++++++++++++++++-------------------
 1 file changed, 21 insertions(+), 19 deletions(-)

diff --git a/lib/fluent/supervisor.rb b/lib/fluent/supervisor.rb
index 4c57048809..487d0d04e6 100644
--- a/lib/fluent/supervisor.rb
+++ b/lib/fluent/supervisor.rb
@@ -215,39 +215,41 @@ def install_windows_event_handler
       Thread.new do
         ipc = Win32::Ipc.new(nil)
         events = [
-          Win32::Event.new("#{@pid_signame}_STOP_EVENT_THREAD"),
-          Win32::Event.new("#{@pid_signame}"),
-          Win32::Event.new("#{@pid_signame}_HUP"),
-          Win32::Event.new("#{@pid_signame}_USR1"),
-          Win32::Event.new("#{@pid_signame}_USR2"),
+          {win32_event: Win32::Event.new("#{@pid_signame}_STOP_EVENT_THREAD"), action: :stop_event_thread},
+          {win32_event: Win32::Event.new("#{@pid_signame}"), action: :stop},
+          {win32_event: Win32::Event.new("#{@pid_signame}_HUP"), action: :hup},
+          {win32_event: Win32::Event.new("#{@pid_signame}_USR1"), action: :usr1},
+          {win32_event: Win32::Event.new("#{@pid_signame}_USR2"), action: :usr2},
         ]
         if @signame
           signame_events = [
-            Win32::Event.new("#{@signame}"),
-            Win32::Event.new("#{@signame}_HUP"),
-            Win32::Event.new("#{@signame}_USR1"),
-            Win32::Event.new("#{@signame}_USR2"),
+            {win32_event: Win32::Event.new("#{@signame}"), action: :stop},
+            {win32_event: Win32::Event.new("#{@signame}_HUP"), action: :hup},
+            {win32_event: Win32::Event.new("#{@signame}_USR1"), action: :usr1},
+            {win32_event: Win32::Event.new("#{@signame}_USR2"), action: :usr2},
           ]
           events.concat(signame_events)
         end
         begin
           loop do
-            idx = ipc.wait_any(events, Windows::Synchronize::INFINITE)
-            if idx > 0 && idx <= events.length
-              $log.debug("Got Win32 event \"#{events[idx - 1].name}\"")
+            ipc_idx = ipc.wait_any(events.map {|e| e[:win32_event]}, Windows::Synchronize::INFINITE)
+            event_idx = ipc_idx - 1
+
+            if event_idx >= 0 && event_idx < events.length
+              $log.debug("Got Win32 event \"#{events[event_idx][:win32_event].name}\"")
             else
-              $log.warn("Unexpected reutrn value of Win32::Ipc#wait_any: #{idx}")
+              $log.warn("Unexpected return value of Win32::Ipc#wait_any: #{ipc_idx}")
             end
-            case idx
-            when 2, 6
+            case events[event_idx][:action]
+            when :stop
               stop(true)
-            when 3, 7
+            when :hup
               supervisor_sighup_handler
-            when 4, 8
+            when :usr1
               supervisor_sigusr1_handler
-            when 5, 9
+            when :usr2
               supervisor_sigusr2_handler
-            when 1
+            when :stop_event_thread
               break
             end
           end

From dcca77aa96a0d94942176dd7532a7e0b2cf699d2 Mon Sep 17 00:00:00 2001
From: Daijiro Fukuda <fukuda@clear-code.com>
Date: Fri, 18 Mar 2022 18:43:16 +0900
Subject: [PATCH 02/15] Add dump func to fluent-ctl

TODO

- add test-codes
- support winsvc
- consider about supporting rpc
- consider about supporting the next error which occurs without `/tmp` dir.
 (`Sigdump.dump` outputs to `/tmp/sigdump-{pid}.log` by default)

error: `failed to dump: No such file or directory @ rb_sysopen - /tmp/sigdump-{pid}.log`

Signed-off-by: Daijiro Fukuda <fukuda@clear-code.com>
---
 lib/fluent/command/ctl.rb |  3 +++
 lib/fluent/supervisor.rb  | 45 +++++++++++++++++++++++++++++++++++++++
 2 files changed, 48 insertions(+)

diff --git a/lib/fluent/command/ctl.rb b/lib/fluent/command/ctl.rb
index a042c989e2..5036f72dcf 100644
--- a/lib/fluent/command/ctl.rb
+++ b/lib/fluent/command/ctl.rb
@@ -36,6 +36,7 @@ class Ctl
         restart: "HUP",
         flush: "USR1",
         reload: "USR2",
+        dump: "CONT",
       }
       WINSVC_CONTROL_CODE_MAP = {
         shutdown: SERVICE_CONTROL_STOP,
@@ -44,6 +45,7 @@ class Ctl
         restart: 128,
         flush: 129,
         reload: SERVICE_CONTROL_PARAMCHANGE,
+        # dump: 130? TODO support svc control
       }
     else
       COMMAND_MAP = {
@@ -51,6 +53,7 @@ class Ctl
         restart: :HUP,
         flush: :USR1,
         reload: :USR2,
+        dump: "CONT",
       }
     end
 
diff --git a/lib/fluent/supervisor.rb b/lib/fluent/supervisor.rb
index 487d0d04e6..d74ca1cc26 100644
--- a/lib/fluent/supervisor.rb
+++ b/lib/fluent/supervisor.rb
@@ -186,6 +186,11 @@ def install_supervisor_signal_handlers
         $log.debug 'fluentd supervisor process got SIGUSR2'
         supervisor_sigusr2_handler
       end
+
+      trap :CONT do
+        $log.debug 'fluentd supervisor process got CONT'
+        supervisor_sigcont_handler
+      end
     end
 
     if Fluent.windows?
@@ -220,6 +225,7 @@ def install_windows_event_handler
           {win32_event: Win32::Event.new("#{@pid_signame}_HUP"), action: :hup},
           {win32_event: Win32::Event.new("#{@pid_signame}_USR1"), action: :usr1},
           {win32_event: Win32::Event.new("#{@pid_signame}_USR2"), action: :usr2},
+          {win32_event: Win32::Event.new("#{@pid_signame}_CONT"), action: :cont},
         ]
         if @signame
           signame_events = [
@@ -227,6 +233,7 @@ def install_windows_event_handler
             {win32_event: Win32::Event.new("#{@signame}_HUP"), action: :hup},
             {win32_event: Win32::Event.new("#{@signame}_USR1"), action: :usr1},
             {win32_event: Win32::Event.new("#{@signame}_USR2"), action: :usr2},
+            {win32_event: Win32::Event.new("#{@signame}_CONT"), action: :cont},
           ]
           events.concat(signame_events)
         end
@@ -249,6 +256,8 @@ def install_windows_event_handler
               supervisor_sigusr1_handler
             when :usr2
               supervisor_sigusr2_handler
+            when :cont
+              supervisor_sigcont_handler
             when :stop_event_thread
               break
             end
@@ -304,6 +313,21 @@ def supervisor_sigusr2_handler
       $log.error "Failed to reload config file: #{e}"
     end
 
+    def supervisor_sigcont_handler
+      if Fluent.windows?
+        $log.info "dump file. [pid:#{Process.pid}]"
+        require 'sigdump'
+        Sigdump.dump
+      else
+        Process.kill :CONT, Process.pid
+      end
+
+      # TODO should do `reopen_log`?
+      send_signal_to_workers(:CONT)
+    rescue => e
+      $log.error "failed to dump: #{e}"
+    end
+
     def kill_worker
       if config[:worker_pid]
         pids = config[:worker_pid].clone
@@ -360,6 +384,14 @@ def send_command_to_workers(signal)
         restart(true)
       when :USR2
         reload
+      when :CONT
+        dump_all_windows_workers
+      end
+    end
+
+    def dump_all_windows_workers
+      @monitors.each do |m|
+        m.send_command("DUMP\n")
       end
     end
   end
@@ -898,6 +930,9 @@ def install_main_process_command_handlers
           when "RELOAD"
             $log.debug "fluentd main process get #{cmd} command"
             reload_config
+          when "DUMP"
+            $log.debug "fluentd main process get #{cmd} command"
+            dump
           else
             $log.warn "fluentd main process get unknown command [#{cmd}]"
           end
@@ -947,6 +982,16 @@ def reload_config
       end
     end
 
+    def dump
+      # Intended for use on Windows
+      # TODO should put these codes inside of a new thread block?
+      $log.info("dump file. [pid:#{Process.pid}]")
+      require 'sigdump'
+      Sigdump.dump
+    rescue => e
+      $log.error("failed to dump: #{e}")
+    end
+
     def logging_with_console_output
       yield $log
       unless @log.stdout?

From 861493fbd405734553f3364d77dee404b7052db6 Mon Sep 17 00:00:00 2001
From: Daijiro Fukuda <fukuda@clear-code.com>
Date: Tue, 22 Mar 2022 00:24:51 +0900
Subject: [PATCH 03/15] Unify by symbol

Signed-off-by: Daijiro Fukuda <fukuda@clear-code.com>
---
 lib/fluent/command/ctl.rb | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/fluent/command/ctl.rb b/lib/fluent/command/ctl.rb
index 5036f72dcf..a19cfd88e4 100644
--- a/lib/fluent/command/ctl.rb
+++ b/lib/fluent/command/ctl.rb
@@ -53,7 +53,7 @@ class Ctl
         restart: :HUP,
         flush: :USR1,
         reload: :USR2,
-        dump: "CONT",
+        dump: :CONT,
       }
     end
 

From 337b0998932f1a6a69c70fd1afadceb4a8af98f1 Mon Sep 17 00:00:00 2001
From: Daijiro Fukuda <fukuda@clear-code.com>
Date: Tue, 22 Mar 2022 00:32:15 +0900
Subject: [PATCH 04/15] Add rpc `api/processes.dump`

Signed-off-by: Daijiro Fukuda <fukuda@clear-code.com>
---
 lib/fluent/supervisor.rb | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/lib/fluent/supervisor.rb b/lib/fluent/supervisor.rb
index d74ca1cc26..10c2b8ad36 100644
--- a/lib/fluent/supervisor.rb
+++ b/lib/fluent/supervisor.rb
@@ -106,6 +106,11 @@ def run_rpc_server
         end
         nil
       }
+      @rpc_server.mount_proc('/api/processes.dump') { |req, res|
+        $log.debug "fluentd RPC got /api/processes.dump request"
+        supervisor_sigcont_handler
+        nil
+      }
       @rpc_server.mount_proc('/api/plugins.flushBuffers') { |req, res|
         $log.debug "fluentd RPC got /api/plugins.flushBuffers request"
         if Fluent.windows?

From 97bc7a0c9f73781492aa9dd47a99ccbd73fcb2c5 Mon Sep 17 00:00:00 2001
From: Daijiro Fukuda <fukuda@clear-code.com>
Date: Tue, 22 Mar 2022 01:16:23 +0900
Subject: [PATCH 05/15] Support SVC control for Windows Service

Signed-off-by: Daijiro Fukuda <fukuda@clear-code.com>
---
 lib/fluent/command/ctl.rb | 2 +-
 lib/fluent/winsvc.rb      | 2 ++
 2 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/lib/fluent/command/ctl.rb b/lib/fluent/command/ctl.rb
index a19cfd88e4..d740753f81 100644
--- a/lib/fluent/command/ctl.rb
+++ b/lib/fluent/command/ctl.rb
@@ -45,7 +45,7 @@ class Ctl
         restart: 128,
         flush: 129,
         reload: SERVICE_CONTROL_PARAMCHANGE,
-        # dump: 130? TODO support svc control
+        dump: 130,
       }
     else
       COMMAND_MAP = {
diff --git a/lib/fluent/winsvc.rb b/lib/fluent/winsvc.rb
index d1b893168d..8cfb807e43 100644
--- a/lib/fluent/winsvc.rb
+++ b/lib/fluent/winsvc.rb
@@ -84,6 +84,8 @@ def service_user_defined_control(code)
         set_event("#{@service_name}_HUP")
       when 129
         set_event("#{@service_name}_USR1")
+      when 130
+        set_event("#{@service_name}_CONT")
       end
     end
 

From 50dbfa6d07af52d312e42f72a421b5f043ace677 Mon Sep 17 00:00:00 2001
From: Daijiro Fukuda <fukuda@clear-code.com>
Date: Tue, 22 Mar 2022 10:49:24 +0900
Subject: [PATCH 06/15] Fix undefined method error

Signed-off-by: Daijiro Fukuda <fukuda@clear-code.com>
---
 lib/fluent/supervisor.rb | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/fluent/supervisor.rb b/lib/fluent/supervisor.rb
index 10c2b8ad36..b8e4340219 100644
--- a/lib/fluent/supervisor.rb
+++ b/lib/fluent/supervisor.rb
@@ -268,7 +268,7 @@ def install_windows_event_handler
             end
           end
         ensure
-          events.each { |event| event.close }
+          events.each { |event| event[:win32_event].close }
         end
       end
     end

From 42b581e4cefc89f4db342fd436fde60294146cf1 Mon Sep 17 00:00:00 2001
From: Daijiro Fukuda <fukuda@clear-code.com>
Date: Tue, 22 Mar 2022 15:30:51 +0900
Subject: [PATCH 07/15] Add test

A class definition in `test_in_object_space` was making Sigdump fail.
This is because `ObjectSpace.each_object` iterates all classes defined.
I have fixed this so that `FailObject.class` raises an error only in
`test_in_object_space`.

Signed-off-by: Daijiro Fukuda <fukuda@clear-code.com>
---
 test/plugin/test_in_object_space.rb | 12 +++++++++---
 test/test_supervisor.rb             | 26 ++++++++++++++++++++++++++
 2 files changed, 35 insertions(+), 3 deletions(-)

diff --git a/test/plugin/test_in_object_space.rb b/test/plugin/test_in_object_space.rb
index ef3c6d2b68..6e8bfa524b 100644
--- a/test/plugin/test_in_object_space.rb
+++ b/test/plugin/test_in_object_space.rb
@@ -17,13 +17,19 @@ def waiting(seconds, instance)
   end
 
   class FailObject
-    def self.class
-      raise "error"
-    end
   end
 
   def setup
     Fluent::Test.setup
+    # Overriding this behavior in the global scope will have an unexpected influence on other tests.
+    # So this should be overridden here and be removed in `teardown`.
+    def FailObject.class
+      raise "FailObject error for tests in ObjectSpaceInputTest."
+    end
+  end
+
+  def teardown
+    FailObject.singleton_class.remove_method(:class)
   end
 
   TESTCONFIG = %[
diff --git a/test/test_supervisor.rb b/test/test_supervisor.rb
index 9b6ca82195..8c23780df8 100644
--- a/test/test_supervisor.rb
+++ b/test/test_supervisor.rb
@@ -213,6 +213,32 @@ def server.config
     $log.out.reset if $log && $log.out && $log.out.respond_to?(:reset)
   end
 
+  def test_supervisor_event_dump_windows
+    omit "Only for Windows, alternative to UNIX signals" unless Fluent.windows?
+
+    ENV['SIGDUMP_PATH'] = TMP_DIR + "/sigdump.log"
+
+    server = DummyServer.new
+    def server.config
+      {:signame => "TestFluentdEvent"}
+    end
+    server.install_windows_event_handler
+    begin
+      sleep 0.1 # Wait for starting windows event thread
+      event = Win32::Event.open("TestFluentdEvent_CONT")
+      event.set
+      event.close
+      sleep 1.0 # Wait for dumping
+    ensure
+      server.stop_windows_event_thread
+    end
+
+    result_filepaths = Dir.glob("#{TMP_DIR}/*")
+    assert {result_filepaths.length > 0}
+  ensure
+    ENV.delete('SIGDUMP_PATH')
+  end
+
   data(:ipv4 => ["0.0.0.0", "127.0.0.1", false],
        :ipv6 => ["[::]", "[::1]", true],
        :localhost_ipv4 => ["localhost", "127.0.0.1", false])

From 1a461476effe82c93c9e16d3dd49ac666707d986 Mon Sep 17 00:00:00 2001
From: Daijiro Fukuda <fukuda@clear-code.com>
Date: Tue, 22 Mar 2022 16:17:06 +0900
Subject: [PATCH 08/15] Support the case where `/tmp` dir doesn't exist on
 Windows

Signed-off-by: Daijiro Fukuda <fukuda@clear-code.com>
---
 lib/fluent/supervisor.rb | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/lib/fluent/supervisor.rb b/lib/fluent/supervisor.rb
index b8e4340219..7359b77429 100644
--- a/lib/fluent/supervisor.rb
+++ b/lib/fluent/supervisor.rb
@@ -321,6 +321,18 @@ def supervisor_sigusr2_handler
     def supervisor_sigcont_handler
       if Fluent.windows?
         $log.info "dump file. [pid:#{Process.pid}]"
+
+        # Sigdump outputs under `/tmp` dir without `SIGDUMP_PATH` specified
+        # but `/tmp` dir may not exist on Windows by default.
+        # Since this function is mainly for Windows, this case should be saved.
+        # (Don't want to couple tightly with the Sigdump library but want to save this case especially.)
+        unless ENV['SIGDUMP_PATH']
+          dump_dir = '/tmp'
+          unless Dir.exist?(dump_dir)
+            FileUtils.mkdir_p(dump_dir, mode: Fluent::DEFAULT_DIR_PERMISSION)
+          end
+        end
+
         require 'sigdump'
         Sigdump.dump
       else

From b6f9b35b5787817461f86f7a6446d3347199c8b6 Mon Sep 17 00:00:00 2001
From: Daijiro Fukuda <fukuda@clear-code.com>
Date: Tue, 22 Mar 2022 17:49:52 +0900
Subject: [PATCH 09/15] Fix problem where CONT signal is sent infinitely on
 UNIX-like

Signed-off-by: Daijiro Fukuda <fukuda@clear-code.com>
---
 lib/fluent/supervisor.rb | 20 ++++++++++++++------
 1 file changed, 14 insertions(+), 6 deletions(-)

diff --git a/lib/fluent/supervisor.rb b/lib/fluent/supervisor.rb
index 7359b77429..1f4cd4591e 100644
--- a/lib/fluent/supervisor.rb
+++ b/lib/fluent/supervisor.rb
@@ -108,7 +108,11 @@ def run_rpc_server
       }
       @rpc_server.mount_proc('/api/processes.dump') { |req, res|
         $log.debug "fluentd RPC got /api/processes.dump request"
-        supervisor_sigcont_handler
+        if Fluent.windows?
+          supervisor_sigcont_handler
+        else
+          Process.kill :CONT, $$
+        end
         nil
       }
       @rpc_server.mount_proc('/api/plugins.flushBuffers') { |req, res|
@@ -332,14 +336,18 @@ def supervisor_sigcont_handler
             FileUtils.mkdir_p(dump_dir, mode: Fluent::DEFAULT_DIR_PERMISSION)
           end
         end
+      end
 
+      # Need new thread to dump in UNIX-like.
+      # (For some reason it seems to work fine on Windows with the original thread.)
+      Thread.new do
+        # As for UNIX-like, `kill CONT` signal is trapped by the supervisor process,
+        # so we have to dump manually for the supervisor process.
+        # (Normally, the dump is automatic with the signal by using `require 'sigdump/setup'`.)
         require 'sigdump'
         Sigdump.dump
-      else
-        Process.kill :CONT, Process.pid
       end
 
-      # TODO should do `reopen_log`?
       send_signal_to_workers(:CONT)
     rescue => e
       $log.error "failed to dump: #{e}"
@@ -1000,8 +1008,8 @@ def reload_config
     end
 
     def dump
-      # Intended for use on Windows
-      # TODO should put these codes inside of a new thread block?
+      raise "[BUG] The `dump` function of workers is for Windows ONLY." unless Fluent.windows?
+      # May need to create a new thread for UNIX-like.
       $log.info("dump file. [pid:#{Process.pid}]")
       require 'sigdump'
       Sigdump.dump

From 65407e59a5200e21d1449815b4a310073cf27976 Mon Sep 17 00:00:00 2001
From: Daijiro Fukuda <fukuda@clear-code.com>
Date: Wed, 23 Mar 2022 08:56:52 +0900
Subject: [PATCH 10/15] Change sigdump path on Windows

To "%windir%/Temp/fluentd-sigdump-#{Process.pid}.log" by default.

When 'SIGDUMP_PATH' environment variable is specified,
add pid to the extension of the path
in order to avoid a conflict of writing to the same file.

Made no modifications for UNIX-like for this commit.
As for UNIX-like, in order to add the same specification,
need to add a trap of SIGCONT to the worker processes
or to fix the Sigdump library.
However, it loses backward compatibility for users using 'SIGDUMP_PATH'
environment variable, so need to consider what to do.

Signed-off-by: Daijiro Fukuda <fukuda@clear-code.com>
---
 lib/fluent/supervisor.rb | 61 +++++++++++++++++++++++-----------------
 test/test_supervisor.rb  | 10 +++++++
 2 files changed, 45 insertions(+), 26 deletions(-)

diff --git a/lib/fluent/supervisor.rb b/lib/fluent/supervisor.rb
index 1f4cd4591e..e3e5d409e4 100644
--- a/lib/fluent/supervisor.rb
+++ b/lib/fluent/supervisor.rb
@@ -16,6 +16,7 @@
 
 require 'fileutils'
 require 'open3'
+require 'pathname'
 
 require 'fluent/config'
 require 'fluent/counter'
@@ -324,30 +325,19 @@ def supervisor_sigusr2_handler
 
     def supervisor_sigcont_handler
       if Fluent.windows?
-        $log.info "dump file. [pid:#{Process.pid}]"
-
-        # Sigdump outputs under `/tmp` dir without `SIGDUMP_PATH` specified
-        # but `/tmp` dir may not exist on Windows by default.
-        # Since this function is mainly for Windows, this case should be saved.
-        # (Don't want to couple tightly with the Sigdump library but want to save this case especially.)
-        unless ENV['SIGDUMP_PATH']
-          dump_dir = '/tmp'
-          unless Dir.exist?(dump_dir)
-            FileUtils.mkdir_p(dump_dir, mode: Fluent::DEFAULT_DIR_PERMISSION)
-          end
+        FluentSigdump.dump_windows
+      else
+        # Need new thread to dump in UNIX-like.
+        # (For some reason it seems to work fine on Windows with the original thread.)
+        Thread.new do
+          # As for UNIX-like, `kill CONT` signal is trapped by the supervisor process,
+          # so we have to dump manually for the supervisor process.
+          # (Normally, the dump is automatic with the signal by using `require 'sigdump/setup'`.)
+          require 'sigdump'
+          Sigdump.dump
         end
       end
 
-      # Need new thread to dump in UNIX-like.
-      # (For some reason it seems to work fine on Windows with the original thread.)
-      Thread.new do
-        # As for UNIX-like, `kill CONT` signal is trapped by the supervisor process,
-        # so we have to dump manually for the supervisor process.
-        # (Normally, the dump is automatic with the signal by using `require 'sigdump/setup'`.)
-        require 'sigdump'
-        Sigdump.dump
-      end
-
       send_signal_to_workers(:CONT)
     rescue => e
       $log.error "failed to dump: #{e}"
@@ -1008,11 +998,7 @@ def reload_config
     end
 
     def dump
-      raise "[BUG] The `dump` function of workers is for Windows ONLY." unless Fluent.windows?
-      # May need to create a new thread for UNIX-like.
-      $log.info("dump file. [pid:#{Process.pid}]")
-      require 'sigdump'
-      Sigdump.dump
+      FluentSigdump.dump_windows
     rescue => e
       $log.error("failed to dump: #{e}")
     end
@@ -1126,4 +1112,27 @@ def build_spawn_command
       fluentd_spawn_cmd
     end
   end
+
+  module FluentSigdump
+    def self.dump_windows
+      raise "[BUG] WindowsSigdump::dump is for Windows ONLY." unless Fluent.windows?
+
+      # Sigdump outputs under `/tmp` dir without `SIGDUMP_PATH` specified,
+      # but `/tmp` dir may not exist on Windows by default.
+      # So use the systemroot-temp-dir instead.
+      dump_filepath = ENV['SIGDUMP_PATH'].nil? || ENV['SIGDUMP_PATH'].empty? \
+        ? "#{ENV['windir']}/Temp/fluentd-sigdump-#{Process.pid}.log"
+        : get_path_with_pid(ENV['SIGDUMP_PATH'])
+
+      require 'sigdump'
+      Sigdump.dump(dump_filepath)
+
+      $log.info "dump to #{dump_filepath}."
+    end
+
+    def self.get_path_with_pid(raw_path)
+      path = Pathname.new(raw_path)
+      path.sub_ext("-#{Process.pid}#{path.extname}").to_s
+    end
+  end
 end
diff --git a/test/test_supervisor.rb b/test/test_supervisor.rb
index 8c23780df8..875c443c37 100644
--- a/test/test_supervisor.rb
+++ b/test/test_supervisor.rb
@@ -213,6 +213,16 @@ def server.config
     $log.out.reset if $log && $log.out && $log.out.respond_to?(:reset)
   end
 
+  data("Normal", {raw_path: "C:\\Windows\\Temp\\sigdump.log", expected: "C:\\Windows\\Temp\\sigdump-#{$$}.log"})
+  data("UNIX style", {raw_path: "/Windows/Temp/sigdump.log", expected: "/Windows/Temp/sigdump-#{$$}.log"})
+  data("No extension", {raw_path: "C:\\Windows\\Temp\\sigdump", expected: "C:\\Windows\\Temp\\sigdump-#{$$}"})
+  data("Multi-extension", {raw_path: "C:\\Windows\\Temp\\sig.dump.bk", expected: "C:\\Windows\\Temp\\sig.dump-#{$$}.bk"})
+  def test_fluentsigdump_get_path_with_pid(data)
+    p data
+    path = Fluent::FluentSigdump.get_path_with_pid(data[:raw_path])
+    assert_equal(data[:expected], path)
+  end
+
   def test_supervisor_event_dump_windows
     omit "Only for Windows, alternative to UNIX signals" unless Fluent.windows?
 

From eac5ce1fd908d98cada9244fbb8225c596abd48a Mon Sep 17 00:00:00 2001
From: Daijiro Fukuda <fukuda@clear-code.com>
Date: Wed, 23 Mar 2022 09:05:07 +0900
Subject: [PATCH 11/15] Fix handler name

to describe its function well

Signed-off-by: Daijiro Fukuda <fukuda@clear-code.com>
---
 lib/fluent/supervisor.rb | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/lib/fluent/supervisor.rb b/lib/fluent/supervisor.rb
index e3e5d409e4..5aee227e29 100644
--- a/lib/fluent/supervisor.rb
+++ b/lib/fluent/supervisor.rb
@@ -110,7 +110,7 @@ def run_rpc_server
       @rpc_server.mount_proc('/api/processes.dump') { |req, res|
         $log.debug "fluentd RPC got /api/processes.dump request"
         if Fluent.windows?
-          supervisor_sigcont_handler
+          supervisor_dump_handler
         else
           Process.kill :CONT, $$
         end
@@ -199,7 +199,7 @@ def install_supervisor_signal_handlers
 
       trap :CONT do
         $log.debug 'fluentd supervisor process got CONT'
-        supervisor_sigcont_handler
+        supervisor_dump_handler
       end
     end
 
@@ -267,7 +267,7 @@ def install_windows_event_handler
             when :usr2
               supervisor_sigusr2_handler
             when :cont
-              supervisor_sigcont_handler
+              supervisor_dump_handler
             when :stop_event_thread
               break
             end
@@ -323,7 +323,7 @@ def supervisor_sigusr2_handler
       $log.error "Failed to reload config file: #{e}"
     end
 
-    def supervisor_sigcont_handler
+    def supervisor_dump_handler
       if Fluent.windows?
         FluentSigdump.dump_windows
       else

From 9d0d1f331dda7a10d76a102b514096719cb8248e Mon Sep 17 00:00:00 2001
From: Daijiro Fukuda <fukuda@clear-code.com>
Date: Wed, 23 Mar 2022 16:10:25 +0900
Subject: [PATCH 12/15] Abolish SIGCONT trap on UNIX-like

Shouldn't change SIGCONT behavior on UNIX-like for backward compatibility.
The rpc dump command is a new function, so make it send SIGCONT to all fluentd
processes.

With `SIGDUMP_PATH` environment variable specified on UNIX-like,
the rpc dump command will cause a writing conflict.
This should be fixed by improving the Sigdump library so that we can
specify a directory path.

Signed-off-by: Daijiro Fukuda <fukuda@clear-code.com>
---
 lib/fluent/supervisor.rb | 32 +++++++++++---------------------
 1 file changed, 11 insertions(+), 21 deletions(-)

diff --git a/lib/fluent/supervisor.rb b/lib/fluent/supervisor.rb
index 5aee227e29..ff73bf04fb 100644
--- a/lib/fluent/supervisor.rb
+++ b/lib/fluent/supervisor.rb
@@ -110,9 +110,10 @@ def run_rpc_server
       @rpc_server.mount_proc('/api/processes.dump') { |req, res|
         $log.debug "fluentd RPC got /api/processes.dump request"
         if Fluent.windows?
-          supervisor_dump_handler
+          supervisor_dump_handler_for_windows
         else
           Process.kill :CONT, $$
+          send_signal_to_workers(:CONT)
         end
         nil
       }
@@ -196,11 +197,6 @@ def install_supervisor_signal_handlers
         $log.debug 'fluentd supervisor process got SIGUSR2'
         supervisor_sigusr2_handler
       end
-
-      trap :CONT do
-        $log.debug 'fluentd supervisor process got CONT'
-        supervisor_dump_handler
-      end
     end
 
     if Fluent.windows?
@@ -267,7 +263,7 @@ def install_windows_event_handler
             when :usr2
               supervisor_sigusr2_handler
             when :cont
-              supervisor_dump_handler
+              supervisor_dump_handler_for_windows
             when :stop_event_thread
               break
             end
@@ -323,20 +319,14 @@ def supervisor_sigusr2_handler
       $log.error "Failed to reload config file: #{e}"
     end
 
-    def supervisor_dump_handler
-      if Fluent.windows?
-        FluentSigdump.dump_windows
-      else
-        # Need new thread to dump in UNIX-like.
-        # (For some reason it seems to work fine on Windows with the original thread.)
-        Thread.new do
-          # As for UNIX-like, `kill CONT` signal is trapped by the supervisor process,
-          # so we have to dump manually for the supervisor process.
-          # (Normally, the dump is automatic with the signal by using `require 'sigdump/setup'`.)
-          require 'sigdump'
-          Sigdump.dump
-        end
-      end
+    def supervisor_dump_handler_for_windows
+      # As for UNIX-like, SIGCONT signal to each process makes the process output its dump-file,
+      # and it is implemented before the implementation of the function for Windows.
+      # It is possible to trap SIGCONT and handle it here also on UNIX-like,
+      # but for backward compatibility, this handler is currently for a Windows-only.
+      raise "[BUG] This function is for Windows ONLY." unless Fluent.windows?
+
+      FluentSigdump.dump_windows
 
       send_signal_to_workers(:CONT)
     rescue => e

From dafde43966c1029581d0dd065b368d3db7cbe41e Mon Sep 17 00:00:00 2001
From: Daijiro Fukuda <fukuda@clear-code.com>
Date: Wed, 23 Mar 2022 17:01:21 +0900
Subject: [PATCH 13/15] Wrap Windows dump process with a new thread

In order not to block the waiting thread.

Signed-off-by: Daijiro Fukuda <fukuda@clear-code.com>
---
 lib/fluent/supervisor.rb | 18 ++++++++++++++----
 1 file changed, 14 insertions(+), 4 deletions(-)

diff --git a/lib/fluent/supervisor.rb b/lib/fluent/supervisor.rb
index ff73bf04fb..f9e961c126 100644
--- a/lib/fluent/supervisor.rb
+++ b/lib/fluent/supervisor.rb
@@ -326,7 +326,13 @@ def supervisor_dump_handler_for_windows
       # but for backward compatibility, this handler is currently for a Windows-only.
       raise "[BUG] This function is for Windows ONLY." unless Fluent.windows?
 
-      FluentSigdump.dump_windows
+      Thread.new do
+        begin
+          FluentSigdump.dump_windows
+        rescue => e
+          $log.error "failed to dump: #{e}"
+        end
+      end
 
       send_signal_to_workers(:CONT)
     rescue => e
@@ -988,9 +994,13 @@ def reload_config
     end
 
     def dump
-      FluentSigdump.dump_windows
-    rescue => e
-      $log.error("failed to dump: #{e}")
+      Thread.new do
+        begin
+          FluentSigdump.dump_windows
+        rescue => e
+          $log.error("failed to dump: #{e}")
+        end
+      end
     end
 
     def logging_with_console_output

From 0d126dedf131637fad7d6dabf8a9c86fd5cf3eca Mon Sep 17 00:00:00 2001
From: Daijiro Fukuda <fukuda@clear-code.com>
Date: Thu, 24 Mar 2022 15:09:24 +0900
Subject: [PATCH 14/15] Fix failing test

This test works fine on its own, but some other tests make it fail.
Use mock to solve this problem.

Signed-off-by: Daijiro Fukuda <fukuda@clear-code.com>
---
 test/test_supervisor.rb | 37 ++++++++++++++++++++++---------------
 1 file changed, 22 insertions(+), 15 deletions(-)

diff --git a/test/test_supervisor.rb b/test/test_supervisor.rb
index 875c443c37..b2b9b76dca 100644
--- a/test/test_supervisor.rb
+++ b/test/test_supervisor.rb
@@ -226,27 +226,34 @@ def test_fluentsigdump_get_path_with_pid(data)
   def test_supervisor_event_dump_windows
     omit "Only for Windows, alternative to UNIX signals" unless Fluent.windows?
 
-    ENV['SIGDUMP_PATH'] = TMP_DIR + "/sigdump.log"
-
     server = DummyServer.new
     def server.config
       {:signame => "TestFluentdEvent"}
     end
     server.install_windows_event_handler
-    begin
-      sleep 0.1 # Wait for starting windows event thread
-      event = Win32::Event.open("TestFluentdEvent_CONT")
-      event.set
-      event.close
-      sleep 1.0 # Wait for dumping
-    ensure
-      server.stop_windows_event_thread
-    end
 
-    result_filepaths = Dir.glob("#{TMP_DIR}/*")
-    assert {result_filepaths.length > 0}
-  ensure
-    ENV.delete('SIGDUMP_PATH')
+    assert_rr do
+      # Have to use mock because `Sigdump.dump` seems to be somehow incompatible with RR.
+      # The `mock(server).restart(true) { nil }` line in `test_rpc_server_windows` cause the next error.
+      # Failure: test_supervisor_event_dump_windows(SupervisorTest):
+      #   class()
+      #   Called 0 times.
+      #   Expected 1 times.
+      # .../Ruby26-x64/lib/ruby/gems/2.6.0/gems/sigdump-0.2.4/lib/sigdump.rb:74:in `block in dump_object_count'
+      #     73: ObjectSpace.each_object {|o|
+      #     74:   c = o.class <-- HERE!
+      mock(Sigdump).dump(anything)
+
+      begin
+        sleep 0.1 # Wait for starting windows event thread
+        event = Win32::Event.open("TestFluentdEvent_CONT")
+        event.set
+        event.close
+        sleep 1.0 # Wait for dumping
+      ensure
+        server.stop_windows_event_thread
+      end
+    end
   end
 
   data(:ipv4 => ["0.0.0.0", "127.0.0.1", false],

From 4b18c6f34344d455faf75e407927871f1361f6b5 Mon Sep 17 00:00:00 2001
From: Takuro Ashie <ashie@clear-code.com>
Date: Thu, 19 May 2022 18:27:43 +0900
Subject: [PATCH 15/15] Remove RPC API `/api/processes.dump`

There is no actual request from users, and it might introduce security risk.

Signed-off-by: Takuro Ashie <ashie@clear-code.com>
---
 lib/fluent/supervisor.rb | 10 ----------
 1 file changed, 10 deletions(-)

diff --git a/lib/fluent/supervisor.rb b/lib/fluent/supervisor.rb
index f9e961c126..5c6c90b693 100644
--- a/lib/fluent/supervisor.rb
+++ b/lib/fluent/supervisor.rb
@@ -107,16 +107,6 @@ def run_rpc_server
         end
         nil
       }
-      @rpc_server.mount_proc('/api/processes.dump') { |req, res|
-        $log.debug "fluentd RPC got /api/processes.dump request"
-        if Fluent.windows?
-          supervisor_dump_handler_for_windows
-        else
-          Process.kill :CONT, $$
-          send_signal_to_workers(:CONT)
-        end
-        nil
-      }
       @rpc_server.mount_proc('/api/plugins.flushBuffers') { |req, res|
         $log.debug "fluentd RPC got /api/plugins.flushBuffers request"
         if Fluent.windows?