1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
|
// +build !windows
// Copyright 2019 The Gitea Authors. All rights reserved.
// Use of this source code is governed by a MIT-style
// license that can be found in the LICENSE file.
package graceful
import (
"context"
"errors"
"os"
"os/signal"
"sync"
"syscall"
"time"
"code.gitea.io/gitea/modules/log"
"code.gitea.io/gitea/modules/setting"
)
// Manager manages the graceful shutdown process
type Manager struct {
isChild bool
forked bool
lock *sync.RWMutex
state state
shutdownCtx context.Context
hammerCtx context.Context
terminateCtx context.Context
doneCtx context.Context
shutdownCtxCancel context.CancelFunc
hammerCtxCancel context.CancelFunc
terminateCtxCancel context.CancelFunc
doneCtxCancel context.CancelFunc
runningServerWaitGroup sync.WaitGroup
createServerWaitGroup sync.WaitGroup
terminateWaitGroup sync.WaitGroup
toRunAtShutdown []func()
toRunAtHammer []func()
toRunAtTerminate []func()
}
func newGracefulManager(ctx context.Context) *Manager {
manager := &Manager{
isChild: len(os.Getenv(listenFDs)) > 0 && os.Getppid() > 1,
lock: &sync.RWMutex{},
}
manager.createServerWaitGroup.Add(numberOfServersToCreate)
manager.start(ctx)
return manager
}
func (g *Manager) start(ctx context.Context) {
// Make contexts
g.terminateCtx, g.terminateCtxCancel = context.WithCancel(ctx)
g.shutdownCtx, g.shutdownCtxCancel = context.WithCancel(ctx)
g.hammerCtx, g.hammerCtxCancel = context.WithCancel(ctx)
g.doneCtx, g.doneCtxCancel = context.WithCancel(ctx)
// Set the running state & handle signals
g.setState(stateRunning)
go g.handleSignals(ctx)
// Handle clean up of unused provided listeners and delayed start-up
startupDone := make(chan struct{})
go func() {
defer close(startupDone)
// Wait till we're done getting all of the listeners and then close
// the unused ones
g.createServerWaitGroup.Wait()
// Ignore the error here there's not much we can do with it
// They're logged in the CloseProvidedListeners function
_ = CloseProvidedListeners()
}()
if setting.StartupTimeout > 0 {
go func() {
select {
case <-startupDone:
return
case <-g.IsShutdown():
func() {
// When waitgroup counter goes negative it will panic - we don't care about this so we can just ignore it.
defer func() {
_ = recover()
}()
// Ensure that the createServerWaitGroup stops waiting
for {
g.createServerWaitGroup.Done()
}
}()
return
case <-time.After(setting.StartupTimeout):
log.Error("Startup took too long! Shutting down")
g.doShutdown()
}
}()
}
}
func (g *Manager) handleSignals(ctx context.Context) {
signalChannel := make(chan os.Signal, 1)
signal.Notify(
signalChannel,
syscall.SIGHUP,
syscall.SIGUSR1,
syscall.SIGUSR2,
syscall.SIGINT,
syscall.SIGTERM,
syscall.SIGTSTP,
)
pid := syscall.Getpid()
for {
select {
case sig := <-signalChannel:
switch sig {
case syscall.SIGHUP:
log.Info("PID: %d. Received SIGHUP. Attempting GracefulRestart...", pid)
g.DoGracefulRestart()
case syscall.SIGUSR1:
log.Warn("PID %d. Received SIGUSR1. Releasing and reopening logs", pid)
if err := log.ReleaseReopen(); err != nil {
log.Error("Error whilst releasing and reopening logs: %v", err)
}
case syscall.SIGUSR2:
log.Warn("PID %d. Received SIGUSR2. Hammering...", pid)
g.DoImmediateHammer()
case syscall.SIGINT:
log.Warn("PID %d. Received SIGINT. Shutting down...", pid)
g.DoGracefulShutdown()
case syscall.SIGTERM:
log.Warn("PID %d. Received SIGTERM. Shutting down...", pid)
g.DoGracefulShutdown()
case syscall.SIGTSTP:
log.Info("PID %d. Received SIGTSTP.", pid)
default:
log.Info("PID %d. Received %v.", pid, sig)
}
case <-ctx.Done():
log.Warn("PID: %d. Background context for manager closed - %v - Shutting down...", pid, ctx.Err())
g.DoGracefulShutdown()
}
}
}
func (g *Manager) doFork() error {
g.lock.Lock()
if g.forked {
g.lock.Unlock()
return errors.New("another process already forked. Ignoring this one")
}
g.forked = true
g.lock.Unlock()
// We need to move the file logs to append pids
setting.RestartLogsWithPIDSuffix()
_, err := RestartProcess()
return err
}
// DoGracefulRestart causes a graceful restart
func (g *Manager) DoGracefulRestart() {
if setting.GracefulRestartable {
log.Info("PID: %d. Forking...", os.Getpid())
err := g.doFork()
if err != nil && err.Error() != "another process already forked. Ignoring this one" {
log.Error("Error whilst forking from PID: %d : %v", os.Getpid(), err)
}
} else {
log.Info("PID: %d. Not set restartable. Shutting down...", os.Getpid())
g.doShutdown()
}
}
// DoImmediateHammer causes an immediate hammer
func (g *Manager) DoImmediateHammer() {
g.doHammerTime(0 * time.Second)
}
// DoGracefulShutdown causes a graceful shutdown
func (g *Manager) DoGracefulShutdown() {
g.doShutdown()
}
// RegisterServer registers the running of a listening server, in the case of unix this means that the parent process can now die.
// Any call to RegisterServer must be matched by a call to ServerDone
func (g *Manager) RegisterServer() {
KillParent()
g.runningServerWaitGroup.Add(1)
}
|
