From e18f5a53045d4b2810f56d33b9ff9a8f6a7ae8bf Mon Sep 17 00:00:00 2001
From: Sebastiaan van Stijn <github@gone.nl>
Date: Fri, 18 Aug 2023 16:18:40 +0200
Subject: [PATCH] container: internalize InitAttachContext
Move the initialization logic to the attachContext itself, so that
the container doesn't have to be aware about mutexes and other logic.
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
---
container/attach_context.go | 35 +++++++++++++++++++++++++++++++++++
container/container.go | 26 ++++----------------------
daemon/attach.go | 2 +-
3 files changed, 40 insertions(+), 23 deletions(-)
create mode 100644 container/attach_context.go
diff --git a/container/attach_context.go b/container/attach_context.go
new file mode 100644
index 0000000000..5a7d0748f0
--- /dev/null
+++ b/container/attach_context.go
@@ -0,0 +1,35 @@
+package container
+
+import (
+ "context"
+ "sync"
+)
+
+// attachContext is the context used for for attach calls.
+type attachContext struct {
+ mu sync.Mutex
+ ctx context.Context
+ cancelFunc context.CancelFunc
+}
+
+// init returns the context for attach calls. It creates a new context
+// if no context is created yet.
+func (ac *attachContext) init() context.Context {
+ ac.mu.Lock()
+ defer ac.mu.Unlock()
+ if ac.ctx == nil {
+ ac.ctx, ac.cancelFunc = context.WithCancel(context.Background())
+ }
+ return ac.ctx
+}
+
+// cancelFunc cancels the attachContext. All attach calls should detach
+// after this call.
+func (ac *attachContext) cancel() {
+ ac.mu.Lock()
+ if ac.ctx != nil {
+ ac.cancelFunc()
+ ac.ctx = nil
+ }
+ ac.mu.Unlock()
+}
diff --git a/container/container.go b/container/container.go
index bc21a33881..be492a0fa3 100644
--- a/container/container.go
+++ b/container/container.go
@@ -10,7 +10,6 @@ import (
"path/filepath"
"runtime"
"strings"
- "sync"
"syscall"
"time"
@@ -594,32 +593,15 @@ func (container *Container) ResetRestartManager(resetCount bool) {
container.restartManager = nil
}
-type attachContext struct {
- ctx context.Context
- cancel context.CancelFunc
- mu sync.Mutex
-}
-
-// InitAttachContext initializes or returns existing context for attach calls to
-// track container liveness.
-func (container *Container) InitAttachContext() context.Context {
- container.attachContext.mu.Lock()
- defer container.attachContext.mu.Unlock()
- if container.attachContext.ctx == nil {
- container.attachContext.ctx, container.attachContext.cancel = context.WithCancel(context.Background())
- }
- return container.attachContext.ctx
+// AttachContext returns the context for attach calls to track container liveness.
+func (container *Container) AttachContext() context.Context {
+ return container.attachContext.init()
}
// CancelAttachContext cancels attach context. All attach calls should detach
// after this call.
func (container *Container) CancelAttachContext() {
- container.attachContext.mu.Lock()
- if container.attachContext.ctx != nil {
- container.attachContext.cancel()
- container.attachContext.ctx = nil
- }
- container.attachContext.mu.Unlock()
+ container.attachContext.cancel()
}
func (container *Container) startLogging() error {
diff --git a/daemon/attach.go b/daemon/attach.go
index 18480df5db..9809671134 100644
--- a/daemon/attach.go
+++ b/daemon/attach.go
@@ -175,7 +175,7 @@ func (daemon *Daemon) containerAttach(c *container.Container, cfg *stream.Attach
}()
}
- ctx := c.InitAttachContext()
+ ctx := c.AttachContext()
err := <-c.StreamConfig.CopyStreams(ctx, cfg)
if err != nil {
var ierr term.EscapeError