vendor: initial vendor

Signed-off-by: Tonis Tiigi <tonistiigi@gmail.com>

vendor/github.com/containerd/fifo/handle_linux.go

@@ -0,0 +1,97 @@
+// +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 fifo
+
+import (
+	"fmt"
+	"os"
+	"sync"
+	"syscall"
+
+	"github.com/pkg/errors"
+)
+
+const O_PATH = 010000000
+
+type handle struct {
+	f         *os.File
+	fd        uintptr
+	dev       uint64
+	ino       uint64
+	closeOnce sync.Once
+	name      string
+}
+
+func getHandle(fn string) (*handle, error) {
+	f, err := os.OpenFile(fn, O_PATH, 0)
+	if err != nil {
+		return nil, errors.Wrapf(err, "failed to open %v with O_PATH", fn)
+	}
+
+	var (
+		stat syscall.Stat_t
+		fd   = f.Fd()
+	)
+	if err := syscall.Fstat(int(fd), &stat); err != nil {
+		f.Close()
+		return nil, errors.Wrapf(err, "failed to stat handle %v", fd)
+	}
+
+	h := &handle{
+		f:    f,
+		name: fn,
+		dev:  uint64(stat.Dev),
+		ino:  stat.Ino,
+		fd:   fd,
+	}
+
+	// check /proc just in case
+	if _, err := os.Stat(h.procPath()); err != nil {
+		f.Close()
+		return nil, errors.Wrapf(err, "couldn't stat %v", h.procPath())
+	}
+
+	return h, nil
+}
+
+func (h *handle) procPath() string {
+	return fmt.Sprintf("/proc/self/fd/%d", h.fd)
+}
+
+func (h *handle) Name() string {
+	return h.name
+}
+
+func (h *handle) Path() (string, error) {
+	var stat syscall.Stat_t
+	if err := syscall.Stat(h.procPath(), &stat); err != nil {
+		return "", errors.Wrapf(err, "path %v could not be statted", h.procPath())
+	}
+	if uint64(stat.Dev) != h.dev || stat.Ino != h.ino {
+		return "", errors.Errorf("failed to verify handle %v/%v %v/%v", stat.Dev, h.dev, stat.Ino, h.ino)
+	}
+	return h.procPath(), nil
+}
+
+func (h *handle) Close() error {
+	h.closeOnce.Do(func() {
+		h.f.Close()
+	})
+	return nil
+}