Merge pull request #3545 from estesp/update-fifo

Update fifo vendoring for typed errors

vendor.conf

@@ -2,7 +2,7 @@ github.com/containerd/go-runc 9007c2405372fe28918845901a3276c0915689a1
 github.com/containerd/console 0650fd9eeb50bab4fc99dceb9f2e14cf58f36e7f
 github.com/containerd/cgroups c4b9ac5c7601384c965b9646fc515884e091ebb9
 github.com/containerd/typeurl a93fcdb778cd272c6e9b3028b2f42d813e785d40
-github.com/containerd/fifo 3d5202aec260678c48179c56f40e6f38a095738c
+github.com/containerd/fifo bda0ff6ed73c67bfb5e62bc9c697f146b7fd7f13
 github.com/containerd/btrfs af5082808c833de0e79c1e72eea9fea239364877
 github.com/containerd/continuity bd77b46c8352f74eb12c85bdc01f4b90f69d66b4
 github.com/coreos/go-systemd 48702e0da86bd25e76cfef347e2adeb434a0d0a6

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

@@ -0,0 +1,30 @@
+/*
+   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 (
+	"errors"
+)
+
+var (
+	ErrClosed       = errors.New("fifo closed")
+	ErrCtrlClosed   = errors.New("control of closed fifo")
+	ErrRdFrmWRONLY  = errors.New("reading from write-only fifo")
+	ErrReadClosed   = errors.New("reading from a closed fifo")
+	ErrWrToRDONLY   = errors.New("writing to read-only fifo")
+	ErrWriteClosed  = errors.New("writing to a closed fifo")
+)

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

@@ -147,7 +147,7 @@ func OpenFifo(ctx context.Context, fn string, flag int, perm os.FileMode) (io.Re
 // Read from a fifo to a byte array.
 func (f *fifo) Read(b []byte) (int, error) {
 	if f.flag&syscall.O_WRONLY > 0 {
-		return 0, errors.New("reading from write-only fifo")
+		return 0, ErrRdFrmWRONLY
 	}
 	select {
 	case <-f.opened:
@@ -158,14 +158,14 @@ func (f *fifo) Read(b []byte) (int, error) {
 	case <-f.opened:
 		return f.file.Read(b)
 	case <-f.closed:
-		return 0, errors.New("reading from a closed fifo")
+		return 0, ErrReadClosed
 	}
 }
 
 // Write from byte array to a fifo.
 func (f *fifo) Write(b []byte) (int, error) {
 	if f.flag&(syscall.O_WRONLY|syscall.O_RDWR) == 0 {
-		return 0, errors.New("writing to read-only fifo")
+		return 0, ErrWrToRDONLY
 	}
 	select {
 	case <-f.opened:
@@ -176,7 +176,7 @@ func (f *fifo) Write(b []byte) (int, error) {
 	case <-f.opened:
 		return f.file.Write(b)
 	case <-f.closed:
-		return 0, errors.New("writing to a closed fifo")
+		return 0, ErrWriteClosed
 	}
 }
 

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

@@ -0,0 +1,114 @@
+// +build go1.12
+
+/*
+   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 (
+	"syscall"
+)
+
+// SyscallConn provides raw access to the fifo's underlying filedescrptor.
+// See syscall.Conn for guarentees provided by this interface.
+func (f *fifo) SyscallConn() (syscall.RawConn, error) {
+	// deterministic check for closed
+	select {
+	case <-f.closed:
+		return nil, ErrClosed
+	default:
+	}
+
+	select {
+	case <-f.closed:
+		return nil, ErrClosed
+	case <-f.opened:
+		return f.file.SyscallConn()
+	default:
+	}
+
+	// Not opened and not closed, this means open is non-blocking AND it's not open yet
+	// Use rawConn to deal with non-blocking open.
+	rc := &rawConn{f: f, ready: make(chan struct{})}
+	go func() {
+		select {
+		case <-f.closed:
+			return
+		case <-f.opened:
+			rc.raw, rc.err = f.file.SyscallConn()
+			close(rc.ready)
+		}
+	}()
+
+	return rc, nil
+}
+
+type rawConn struct {
+	f     *fifo
+	ready chan struct{}
+	raw   syscall.RawConn
+	err   error
+}
+
+func (r *rawConn) Control(f func(fd uintptr)) error {
+	select {
+	case <-r.f.closed:
+		return ErrCtrlClosed
+	case <-r.ready:
+	}
+
+	if r.err != nil {
+		return r.err
+	}
+
+	return r.raw.Control(f)
+}
+
+func (r *rawConn) Read(f func(fd uintptr) (done bool)) error {
+	if r.f.flag&syscall.O_WRONLY > 0 {
+		return ErrRdFrmWRONLY
+	}
+
+	select {
+	case <-r.f.closed:
+		return ErrReadClosed
+	case <-r.ready:
+	}
+
+	if r.err != nil {
+		return r.err
+	}
+
+	return r.raw.Read(f)
+}
+
+func (r *rawConn) Write(f func(fd uintptr) (done bool)) error {
+	if r.f.flag&(syscall.O_WRONLY|syscall.O_RDWR) == 0 {
+		return ErrWrToRDONLY
+	}
+
+	select {
+	case <-r.f.closed:
+		return ErrWriteClosed
+	case <-r.ready:
+	}
+
+	if r.err != nil {
+		return r.err
+	}
+
+	return r.raw.Write(f)
+}

vendor/github.com/containerd/fifo/readme.md

@@ -1,6 +1,7 @@
 ### fifo
 
 [![Build Status](https://travis-ci.org/containerd/fifo.svg?branch=master)](https://travis-ci.org/containerd/fifo)
+[![codecov](https://codecov.io/gh/containerd/fifo/branch/master/graph/badge.svg)](https://codecov.io/gh/containerd/fifo)
 
 Go package for handling fifos in a sane way.
 
@@ -30,3 +31,14 @@ func (f *fifo) Write(b []byte) (int, error)
 // before open(2) has returned and fifo was never opened.
 func (f *fifo) Close() error 
 ```
+
+## Project details
+
+The fifo is a containerd sub-project, licensed under the [Apache 2.0 license](./LICENSE).
+As a containerd sub-project, you will find the:
+
+ * [Project governance](https://github.com/containerd/project/blob/master/GOVERNANCE.md),
+ * [Maintainers](https://github.com/containerd/project/blob/master/MAINTAINERS),
+ * and [Contributing guidelines](https://github.com/containerd/project/blob/master/CONTRIBUTING.md)
+
+information in our [`containerd/project`](https://github.com/containerd/project) repository.