containerd/runtime/v2/runc/platform.go
Michael Crosby f8cca26f3c Handle large output in v2 shim with TTY
Reized the I/O buffers to align with the size of the kernel buffers with fifos
and move the close aspect of the console to key off of the stdin closing.

Fixes #3738

Signed-off-by: Michael Crosby <crosbymichael@gmail.com>
2019-10-11 15:42:05 -04:00

124 lines
2.9 KiB
Go

// +build linux
/*
Copyright The containerd Authors.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
package runc
import (
"context"
"io"
"sync"
"syscall"
"github.com/containerd/console"
"github.com/containerd/containerd/pkg/stdio"
"github.com/containerd/fifo"
"github.com/pkg/errors"
)
var bufPool = sync.Pool{
New: func() interface{} {
// setting to 4096 to align with PIPE_BUF
// http://man7.org/linux/man-pages/man7/pipe.7.html
buffer := make([]byte, 4096)
return &buffer
},
}
// NewPlatform returns a linux platform for use with I/O operations
func NewPlatform() (stdio.Platform, error) {
epoller, err := console.NewEpoller()
if err != nil {
return nil, errors.Wrap(err, "failed to initialize epoller")
}
go epoller.Wait()
return &linuxPlatform{
epoller: epoller,
}, nil
}
type linuxPlatform struct {
epoller *console.Epoller
}
func (p *linuxPlatform) CopyConsole(ctx context.Context, console console.Console, stdin, stdout, stderr string, wg *sync.WaitGroup) (console.Console, error) {
if p.epoller == nil {
return nil, errors.New("uninitialized epoller")
}
epollConsole, err := p.epoller.Add(console)
if err != nil {
return nil, err
}
var cwg sync.WaitGroup
if stdin != "" {
in, err := fifo.OpenFifo(context.Background(), stdin, syscall.O_RDONLY|syscall.O_NONBLOCK, 0)
if err != nil {
return nil, err
}
cwg.Add(1)
go func() {
cwg.Done()
bp := bufPool.Get().(*[]byte)
defer bufPool.Put(bp)
io.CopyBuffer(epollConsole, in, *bp)
// we need to shutdown epollConsole when pipe broken
epollConsole.Shutdown(p.epoller.CloseConsole)
epollConsole.Close()
}()
}
outw, err := fifo.OpenFifo(ctx, stdout, syscall.O_WRONLY, 0)
if err != nil {
return nil, err
}
outr, err := fifo.OpenFifo(ctx, stdout, syscall.O_RDONLY, 0)
if err != nil {
return nil, err
}
wg.Add(1)
cwg.Add(1)
go func() {
cwg.Done()
buf := bufPool.Get().(*[]byte)
defer bufPool.Put(buf)
io.CopyBuffer(outw, epollConsole, *buf)
outw.Close()
outr.Close()
wg.Done()
}()
cwg.Wait()
return epollConsole, nil
}
func (p *linuxPlatform) ShutdownConsole(ctx context.Context, cons console.Console) error {
if p.epoller == nil {
return errors.New("uninitialized epoller")
}
epollConsole, ok := cons.(*console.EpollConsole)
if !ok {
return errors.Errorf("expected EpollConsole, got %#v", cons)
}
return epollConsole.Shutdown(p.epoller.CloseConsole)
}
func (p *linuxPlatform) Close() error {
return p.epoller.Close()
}