pax_global_header00006660000000000000000000000064135255676770014541gustar00rootroot0000000000000052 comment=bda0ff6ed73c67bfb5e62bc9c697f146b7fd7f13 golang-github-containerd-fifo-0.0~git20190816.bda0ff6/000077500000000000000000000000001352556767700221405ustar00rootroot00000000000000golang-github-containerd-fifo-0.0~git20190816.bda0ff6/.gitignore000066400000000000000000000000151352556767700241240ustar00rootroot00000000000000coverage.txt golang-github-containerd-fifo-0.0~git20190816.bda0ff6/.travis.yml000066400000000000000000000007101352556767700242470ustar00rootroot00000000000000language: go go: - 1.11.x - tip install: - go get -u github.com/vbatts/git-validation - go get -u github.com/kunalkushwaha/ltag before_script: - pushd ..; git clone https://github.com/containerd/project; popd script: - DCO_VERBOSITY=-q ../project/script/validate/dco - ../project/script/validate/fileheader ../project/ - make deps - make fmt - make vet - make test after_success: - bash <(curl -s https://codecov.io/bash) golang-github-containerd-fifo-0.0~git20190816.bda0ff6/LICENSE000066400000000000000000000261351352556767700231540ustar00rootroot00000000000000 Apache License Version 2.0, January 2004 http://www.apache.org/licenses/ TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION 1. 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See the License for the specific language governing permissions and limitations under the License. golang-github-containerd-fifo-0.0~git20190816.bda0ff6/Makefile000066400000000000000000000014071352556767700236020ustar00rootroot00000000000000# 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. .PHONY: fmt vet test deps test: deps go test -v -race -covermode=atomic -coverprofile=coverage.txt ./... deps: go get -d -t ./... fmt: gofmt -s -l . vet: go vet ./... golang-github-containerd-fifo-0.0~git20190816.bda0ff6/errors.go000066400000000000000000000017241352556767700240070ustar00rootroot00000000000000/* 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") ) golang-github-containerd-fifo-0.0~git20190816.bda0ff6/fifo.go000066400000000000000000000120151352556767700234110ustar00rootroot00000000000000/* 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 ( "io" "os" "runtime" "sync" "syscall" "github.com/pkg/errors" "golang.org/x/net/context" ) type fifo struct { flag int opened chan struct{} closed chan struct{} closing chan struct{} err error file *os.File closingOnce sync.Once // close has been called closedOnce sync.Once // fifo is closed handle *handle } var leakCheckWg *sync.WaitGroup // OpenFifo opens a fifo. Returns io.ReadWriteCloser. // Context can be used to cancel this function until open(2) has not returned. // Accepted flags: // - syscall.O_CREAT - create new fifo if one doesn't exist // - syscall.O_RDONLY - open fifo only from reader side // - syscall.O_WRONLY - open fifo only from writer side // - syscall.O_RDWR - open fifo from both sides, never block on syscall level // - syscall.O_NONBLOCK - return io.ReadWriteCloser even if other side of the // fifo isn't open. read/write will be connected after the actual fifo is // open or after fifo is closed. func OpenFifo(ctx context.Context, fn string, flag int, perm os.FileMode) (io.ReadWriteCloser, error) { if _, err := os.Stat(fn); err != nil { if os.IsNotExist(err) && flag&syscall.O_CREAT != 0 { if err := mkfifo(fn, uint32(perm&os.ModePerm)); err != nil && !os.IsExist(err) { return nil, errors.Wrapf(err, "error creating fifo %v", fn) } } else { return nil, err } } block := flag&syscall.O_NONBLOCK == 0 || flag&syscall.O_RDWR != 0 flag &= ^syscall.O_CREAT flag &= ^syscall.O_NONBLOCK h, err := getHandle(fn) if err != nil { return nil, err } f := &fifo{ handle: h, flag: flag, opened: make(chan struct{}), closed: make(chan struct{}), closing: make(chan struct{}), } wg := leakCheckWg if wg != nil { wg.Add(2) } go func() { if wg != nil { defer wg.Done() } select { case <-ctx.Done(): select { case <-f.opened: default: f.Close() } case <-f.opened: case <-f.closed: } }() go func() { if wg != nil { defer wg.Done() } var file *os.File fn, err := h.Path() if err == nil { file, err = os.OpenFile(fn, flag, 0) } select { case <-f.closing: if err == nil { select { case <-ctx.Done(): err = ctx.Err() default: err = errors.Errorf("fifo %v was closed before opening", h.Name()) } if file != nil { file.Close() } } default: } if err != nil { f.closedOnce.Do(func() { f.err = err close(f.closed) }) return } f.file = file close(f.opened) }() if block { select { case <-f.opened: case <-f.closed: return nil, f.err } } return f, nil } // 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, ErrRdFrmWRONLY } select { case <-f.opened: return f.file.Read(b) default: } select { case <-f.opened: return f.file.Read(b) case <-f.closed: 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, ErrWrToRDONLY } select { case <-f.opened: return f.file.Write(b) default: } select { case <-f.opened: return f.file.Write(b) case <-f.closed: return 0, ErrWriteClosed } } // Close the fifo. Next reads/writes will error. This method can also be used // before open(2) has returned and fifo was never opened. func (f *fifo) Close() (retErr error) { for { select { case <-f.closed: f.handle.Close() return default: select { case <-f.opened: f.closedOnce.Do(func() { retErr = f.file.Close() f.err = retErr close(f.closed) }) default: if f.flag&syscall.O_RDWR != 0 { runtime.Gosched() break } f.closingOnce.Do(func() { close(f.closing) }) reverseMode := syscall.O_WRONLY if f.flag&syscall.O_WRONLY > 0 { reverseMode = syscall.O_RDONLY } fn, err := f.handle.Path() // if Close() is called concurrently(shouldn't) it may cause error // because handle is closed select { case <-f.closed: default: if err != nil { // Path has become invalid. We will leak a goroutine. // This case should not happen in linux. f.closedOnce.Do(func() { f.err = err close(f.closed) }) <-f.closed break } f, err := os.OpenFile(fn, reverseMode|syscall.O_NONBLOCK, 0) if err == nil { f.Close() } runtime.Gosched() } } } } } golang-github-containerd-fifo-0.0~git20190816.bda0ff6/fifo_linux_test.go000066400000000000000000000046111352556767700256720ustar00rootroot00000000000000// +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 ( "io/ioutil" "os" "path/filepath" "sync" "syscall" "testing" "time" "github.com/stretchr/testify/assert" "golang.org/x/net/context" ) func TestFifoCloseAfterRm(t *testing.T) { tmpdir, err := ioutil.TempDir("", "fifos") assert.NoError(t, err) defer os.RemoveAll(tmpdir) leakCheckWg = &sync.WaitGroup{} defer func() { leakCheckWg = nil }() ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second) defer cancel() f, err := OpenFifo(ctx, filepath.Join(tmpdir, "f0"), syscall.O_RDONLY|syscall.O_CREAT|syscall.O_NONBLOCK, 0600) assert.NoError(t, err) err = os.RemoveAll(filepath.Join(tmpdir, "f0")) assert.NoError(t, err) cerr := make(chan error) go func() { b := make([]byte, 32) _, err := f.Read(b) cerr <- err }() select { case err := <-cerr: t.Fatalf("read should have blocked, but got %v", err) case <-time.After(500 * time.Millisecond): } err = f.Close() assert.NoError(t, err) select { case err := <-cerr: assert.EqualError(t, err, "reading from a closed fifo") case <-time.After(500 * time.Millisecond): t.Fatal("read should have been unblocked") } assert.NoError(t, checkWgDone(leakCheckWg)) cancel() ctx, cancel = context.WithCancel(context.Background()) cerr = make(chan error) go func() { _, err = OpenFifo(ctx, filepath.Join(tmpdir, "f1"), syscall.O_WRONLY|syscall.O_CREAT, 0600) cerr <- err }() select { case err := <-cerr: t.Fatalf("open should have blocked, but got %v", err) case <-time.After(500 * time.Millisecond): } err = os.RemoveAll(filepath.Join(tmpdir, "f1")) cancel() select { case err := <-cerr: assert.EqualError(t, err, "context canceled") case <-time.After(500 * time.Millisecond): t.Fatal("open should have been unblocked") } assert.NoError(t, checkWgDone(leakCheckWg)) } golang-github-containerd-fifo-0.0~git20190816.bda0ff6/fifo_nolinux_test.go000066400000000000000000000045511352556767700262320ustar00rootroot00000000000000// +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 ( "io/ioutil" "os" "path/filepath" "syscall" "testing" "time" "github.com/stretchr/testify/assert" "golang.org/x/net/context" ) func TestFifoCloseAfterRm(t *testing.T) { tmpdir, err := ioutil.TempDir("", "fifos") assert.NoError(t, err) defer os.RemoveAll(tmpdir) // non-linux version of this test leaks a goroutine ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second) defer cancel() f, err := OpenFifo(ctx, filepath.Join(tmpdir, "f0"), syscall.O_RDONLY|syscall.O_CREAT|syscall.O_NONBLOCK, 0600) assert.NoError(t, err) time.Sleep(time.Second) // non-linux doesn't allow removing before syscall has been called. will cause an error. err = os.RemoveAll(filepath.Join(tmpdir, "f0")) assert.NoError(t, err) cerr := make(chan error) go func() { b := make([]byte, 32) _, err := f.Read(b) cerr <- err }() select { case err := <-cerr: t.Fatalf("read should have blocked, but got %v", err) case <-time.After(500 * time.Millisecond): } err = f.Close() assert.NoError(t, err) select { case err := <-cerr: assert.EqualError(t, err, "reading from a closed fifo") case <-time.After(500 * time.Millisecond): t.Fatal("read should have been unblocked") } cancel() ctx, cancel = context.WithCancel(context.Background()) cerr = make(chan error) go func() { _, err = OpenFifo(ctx, filepath.Join(tmpdir, "f1"), syscall.O_WRONLY|syscall.O_CREAT, 0600) cerr <- err }() select { case err := <-cerr: t.Fatalf("open should have blocked, but got %v", err) case <-time.After(500 * time.Millisecond): } err = os.RemoveAll(filepath.Join(tmpdir, "f1")) cancel() select { case err := <-cerr: assert.Error(t, err) case <-time.After(500 * time.Millisecond): t.Fatal("open should have been unblocked") } } golang-github-containerd-fifo-0.0~git20190816.bda0ff6/fifo_test.go000066400000000000000000000224331352556767700244550ustar00rootroot00000000000000/* 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 ( "io" "io/ioutil" "os" "path/filepath" "sync" "syscall" "testing" "time" "github.com/stretchr/testify/assert" "golang.org/x/net/context" ) func TestFifoCancel(t *testing.T) { tmpdir, err := ioutil.TempDir("", "fifos") assert.NoError(t, err) defer os.RemoveAll(tmpdir) leakCheckWg = &sync.WaitGroup{} defer func() { leakCheckWg = nil }() _, err = OpenFifo(context.Background(), filepath.Join(tmpdir, "f0"), syscall.O_RDONLY|syscall.O_NONBLOCK, 0600) assert.NotNil(t, err) assert.NoError(t, checkWgDone(leakCheckWg)) ctx, cancel := context.WithTimeout(context.Background(), 500*time.Millisecond) defer cancel() f, err := OpenFifo(ctx, filepath.Join(tmpdir, "f0"), syscall.O_RDONLY|syscall.O_CREAT|syscall.O_NONBLOCK, 0600) assert.NoError(t, err) b := make([]byte, 32) n, err := f.Read(b) assert.Equal(t, n, 0) assert.Equal(t, err, ErrReadClosed) select { case <-ctx.Done(): default: t.Fatal("context should have been done") } assert.NoError(t, checkWgDone(leakCheckWg)) } func TestFifoReadWrite(t *testing.T) { tmpdir, err := ioutil.TempDir("", "fifos") assert.NoError(t, err) defer os.RemoveAll(tmpdir) leakCheckWg = &sync.WaitGroup{} defer func() { leakCheckWg = nil }() ctx, cancel := context.WithTimeout(context.Background(), 2*time.Second) defer cancel() r, err := OpenFifo(ctx, filepath.Join(tmpdir, "f0"), syscall.O_RDONLY|syscall.O_CREAT|syscall.O_NONBLOCK, 0600) assert.NoError(t, err) w, err := OpenFifo(ctx, filepath.Join(tmpdir, "f0"), syscall.O_WRONLY|syscall.O_NONBLOCK, 0) assert.NoError(t, err) _, err = w.Write([]byte("foo")) assert.NoError(t, err) b := make([]byte, 32) n, err := r.Read(b) assert.NoError(t, err) assert.Equal(t, string(b[:n]), "foo") err = r.Close() assert.NoError(t, err) _, err = w.Write([]byte("bar")) assert.NotNil(t, err) assert.NoError(t, checkWgDone(leakCheckWg)) cancel() ctx, cancel = context.WithTimeout(context.Background(), 2*time.Second) defer cancel() w, err = OpenFifo(ctx, filepath.Join(tmpdir, "f1"), syscall.O_CREAT|syscall.O_WRONLY|syscall.O_NONBLOCK, 0600) assert.NoError(t, err) written := make(chan struct{}) go func() { w.Write([]byte("baz")) close(written) }() time.Sleep(200 * time.Millisecond) r, err = OpenFifo(ctx, filepath.Join(tmpdir, "f1"), syscall.O_RDONLY|syscall.O_NONBLOCK, 0) assert.NoError(t, err) n, err = r.Read(b) assert.NoError(t, err) assert.Equal(t, string(b[:n]), "baz") select { case <-written: case <-time.After(500 * time.Millisecond): t.Fatal("content should have been written") } _, err = w.Write([]byte("barbar")) // kernel-buffer assert.NoError(t, err) err = w.Close() assert.NoError(t, err) n, err = r.Read(b) assert.NoError(t, err) assert.Equal(t, string(b[:n]), "barbar") n, err = r.Read(b) assert.Equal(t, n, 0) assert.Equal(t, err, io.EOF) n, err = r.Read(b) assert.Equal(t, n, 0) assert.Equal(t, err, io.EOF) assert.NoError(t, checkWgDone(leakCheckWg)) } func TestFifoCancelOneSide(t *testing.T) { tmpdir, err := ioutil.TempDir("", "fifos") assert.NoError(t, err) defer os.RemoveAll(tmpdir) leakCheckWg = &sync.WaitGroup{} defer func() { leakCheckWg = nil }() ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second) defer cancel() f, err := OpenFifo(ctx, filepath.Join(tmpdir, "f0"), syscall.O_RDONLY|syscall.O_CREAT|syscall.O_NONBLOCK, 0600) assert.NoError(t, err) read := make(chan struct{}) b := make([]byte, 32) go func() { _, err = f.Read(b) close(read) }() select { case <-read: t.Fatal("read should have blocked") case <-time.After(time.Second): } cerr := f.Close() assert.NoError(t, cerr) select { case <-read: case <-time.After(time.Second): t.Fatal("read should have unblocked") } assert.Equal(t, err, ErrReadClosed) assert.NoError(t, checkWgDone(leakCheckWg)) } func TestFifoBlocking(t *testing.T) { tmpdir, err := ioutil.TempDir("", "fifos") assert.NoError(t, err) defer os.RemoveAll(tmpdir) leakCheckWg = &sync.WaitGroup{} defer func() { leakCheckWg = nil }() ctx, cancel := context.WithTimeout(context.Background(), 1*time.Second) defer cancel() _, err = OpenFifo(ctx, filepath.Join(tmpdir, "f0"), syscall.O_RDONLY|syscall.O_CREAT, 0600) assert.EqualError(t, err, "context deadline exceeded") select { case <-ctx.Done(): default: t.Fatal("context should have been completed") } assert.NoError(t, checkWgDone(leakCheckWg)) cancel() ctx, cancel = context.WithTimeout(context.Background(), 2*time.Second) defer cancel() var rerr error var r io.ReadCloser readerOpen := make(chan struct{}) go func() { r, rerr = OpenFifo(ctx, filepath.Join(tmpdir, "f1"), syscall.O_RDONLY|syscall.O_CREAT, 0600) close(readerOpen) }() time.Sleep(500 * time.Millisecond) w, err := OpenFifo(ctx, filepath.Join(tmpdir, "f1"), syscall.O_WRONLY, 0) assert.NoError(t, err) select { case <-readerOpen: case <-time.After(time.Second): t.Fatal("writer should have unblocke reader") } assert.NoError(t, rerr) _, err = w.Write([]byte("foobar")) assert.NoError(t, err) b := make([]byte, 32) n, err := r.Read(b) assert.NoError(t, err) assert.Equal(t, string(b[:n]), "foobar") assert.NoError(t, checkWgDone(leakCheckWg)) err = w.Close() assert.NoError(t, err) n, err = r.Read(b) assert.Equal(t, n, 0) assert.Equal(t, err, io.EOF) assert.NoError(t, checkWgDone(leakCheckWg)) } func TestFifoORDWR(t *testing.T) { tmpdir, err := ioutil.TempDir("", "fifos") assert.NoError(t, err) defer os.RemoveAll(tmpdir) leakCheckWg = &sync.WaitGroup{} defer func() { leakCheckWg = nil }() ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second) defer cancel() f, err := OpenFifo(ctx, filepath.Join(tmpdir, "f0"), syscall.O_RDWR|syscall.O_CREAT, 0600) assert.NoError(t, err) _, err = f.Write([]byte("foobar")) assert.NoError(t, err) b := make([]byte, 32) n, err := f.Read(b) assert.NoError(t, err) assert.Equal(t, string(b[:n]), "foobar") r1, err := OpenFifo(ctx, filepath.Join(tmpdir, "f0"), syscall.O_RDONLY|syscall.O_NONBLOCK, 0) assert.NoError(t, err) _, err = f.Write([]byte("barbar")) assert.NoError(t, err) n, err = r1.Read(b) assert.NoError(t, err) assert.Equal(t, string(b[:n]), "barbar") r2, err := OpenFifo(ctx, filepath.Join(tmpdir, "f0"), syscall.O_RDONLY, 0) assert.NoError(t, err) _, err = f.Write([]byte("barbaz")) assert.NoError(t, err) n, err = r2.Read(b) assert.NoError(t, err) assert.Equal(t, string(b[:n]), "barbaz") err = r2.Close() assert.NoError(t, err) _, err = f.Write([]byte("bar123")) assert.NoError(t, err) n, err = r1.Read(b) assert.NoError(t, err) assert.Equal(t, string(b[:n]), "bar123") err = r1.Close() assert.NoError(t, err) _, err = f.Write([]byte("bar456")) assert.NoError(t, err) r2, err = OpenFifo(ctx, filepath.Join(tmpdir, "f0"), syscall.O_RDONLY, 0) assert.NoError(t, err) n, err = r2.Read(b) assert.NoError(t, err) assert.Equal(t, string(b[:n]), "bar456") err = f.Close() assert.NoError(t, err) n, err = r2.Read(b) assert.EqualError(t, err, io.EOF.Error()) assert.NoError(t, checkWgDone(leakCheckWg)) } func TestFifoCloseError(t *testing.T) { tmpdir, err := ioutil.TempDir("", "fifos") assert.NoError(t, err) defer os.RemoveAll(tmpdir) ctx, cancel := context.WithTimeout(context.Background(), 2*time.Second) defer cancel() w, err := OpenFifo(ctx, filepath.Join(tmpdir, t.Name()), syscall.O_WRONLY|syscall.O_CREAT|syscall.O_NONBLOCK, 0600) assert.NoError(t, err) w.Close() data := []byte("hello world!") _, err = w.Write(data) assert.Equal(t, ErrWriteClosed, err) r, err := OpenFifo(ctx, filepath.Join(tmpdir, t.Name()), syscall.O_RDONLY|syscall.O_CREAT|syscall.O_NONBLOCK, 0600) assert.NoError(t, err) r.Close() buf := make([]byte, len(data)) _, err = r.Read(buf) assert.Equal(t, ErrReadClosed, err) } func TestFifoWrongRdWrError(t *testing.T) { tmpdir, err := ioutil.TempDir("", "fifos") assert.NoError(t, err) defer os.RemoveAll(tmpdir) ctx, cancel := context.WithTimeout(context.Background(), 2*time.Second) defer cancel() r, err := OpenFifo(ctx, filepath.Join(tmpdir, t.Name()), syscall.O_RDONLY|syscall.O_CREAT|syscall.O_NONBLOCK, 0600) assert.NoError(t, err) data := []byte("hello world!") _, err = r.Write(data) assert.Equal(t, ErrWrToRDONLY, err) w, err := OpenFifo(ctx, filepath.Join(tmpdir, t.Name()), syscall.O_WRONLY|syscall.O_CREAT|syscall.O_NONBLOCK, 0600) assert.NoError(t, err) buf := make([]byte, len(data)) _, err = w.Read(buf) assert.Equal(t, ErrRdFrmWRONLY, err) } func checkWgDone(wg *sync.WaitGroup) error { ctx, cancel := context.WithTimeout(context.Background(), 3*time.Second) defer cancel() done := make(chan struct{}) go func() { wg.Wait() // No way to cancel close(done) }() select { case <-done: return nil case <-ctx.Done(): return ctx.Err() } } golang-github-containerd-fifo-0.0~git20190816.bda0ff6/handle_linux.go000066400000000000000000000041001352556767700251340ustar00rootroot00000000000000// +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 } golang-github-containerd-fifo-0.0~git20190816.bda0ff6/handle_nolinux.go000066400000000000000000000027331352556767700255030ustar00rootroot00000000000000// +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 ( "syscall" "github.com/pkg/errors" ) type handle struct { fn string dev uint64 ino uint64 } func getHandle(fn string) (*handle, error) { var stat syscall.Stat_t if err := syscall.Stat(fn, &stat); err != nil { return nil, errors.Wrapf(err, "failed to stat %v", fn) } h := &handle{ fn: fn, dev: uint64(stat.Dev), ino: uint64(stat.Ino), } return h, nil } func (h *handle) Path() (string, error) { var stat syscall.Stat_t if err := syscall.Stat(h.fn, &stat); err != nil { return "", errors.Wrapf(err, "path %v could not be statted", h.fn) } if uint64(stat.Dev) != h.dev || uint64(stat.Ino) != h.ino { return "", errors.Errorf("failed to verify handle %v/%v %v/%v for %v", stat.Dev, h.dev, stat.Ino, h.ino, h.fn) } return h.fn, nil } func (h *handle) Name() string { return h.fn } func (h *handle) Close() error { return nil } golang-github-containerd-fifo-0.0~git20190816.bda0ff6/mkfifo_nosolaris.go000066400000000000000000000013411352556767700260320ustar00rootroot00000000000000// +build !solaris /* 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" func mkfifo(path string, mode uint32) (err error) { return syscall.Mkfifo(path, mode) } golang-github-containerd-fifo-0.0~git20190816.bda0ff6/mkfifo_solaris.go000066400000000000000000000013601352556767700254760ustar00rootroot00000000000000// +build solaris /* 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 ( "golang.org/x/sys/unix" ) func mkfifo(path string, mode uint32) (err error) { return unix.Mkfifo(path, mode) } golang-github-containerd-fifo-0.0~git20190816.bda0ff6/raw.go000066400000000000000000000043001352556767700232550ustar00rootroot00000000000000// +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) } golang-github-containerd-fifo-0.0~git20190816.bda0ff6/raw_test.go000066400000000000000000000154721352556767700243300ustar00rootroot00000000000000// +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 ( "bytes" "io" "io/ioutil" "os" "path" "path/filepath" "syscall" "testing" "time" "github.com/stretchr/testify/assert" "golang.org/x/net/context" ) func TestRawReadWrite(t *testing.T) { tmpdir, err := ioutil.TempDir("", "fifos") assert.NoError(t, err) defer os.RemoveAll(tmpdir) ctx, cancel := context.WithTimeout(context.Background(), 2*time.Second) defer cancel() r, err := OpenFifo(ctx, filepath.Join(tmpdir, t.Name()), syscall.O_RDONLY|syscall.O_CREAT|syscall.O_NONBLOCK, 0600) assert.NoError(t, err) defer r.Close() rawR := makeRawConn(t, r, false) assert.Error(t, rawR.Write(func(uintptr) bool { return true })) w, err := OpenFifo(ctx, filepath.Join(tmpdir, t.Name()), syscall.O_WRONLY|syscall.O_NONBLOCK, 0) assert.NoError(t, err) defer w.Close() rawW := makeRawConn(t, w, false) assert.Error(t, rawW.Read(func(uintptr) bool { return true })) data := []byte("hello world") rawWrite(t, rawW, data) dataR := make([]byte, len(data)) rawRead(t, rawR, dataR) assert.True(t, bytes.Equal(data, dataR)) } func TestRawWriteUserRead(t *testing.T) { tmpdir, err := ioutil.TempDir("", "fifos") assert.NoError(t, err) defer os.RemoveAll(tmpdir) ctx, cancel := context.WithTimeout(context.Background(), 2*time.Second) defer cancel() w, err := OpenFifo(ctx, filepath.Join(tmpdir, t.Name()), syscall.O_WRONLY|syscall.O_CREAT|syscall.O_NONBLOCK, 0600) assert.NoError(t, err) defer w.Close() rawW := makeRawConn(t, w, false) r, err := OpenFifo(ctx, filepath.Join(tmpdir, t.Name()), syscall.O_RDONLY|syscall.O_CREAT|syscall.O_NONBLOCK, 0600) assert.NoError(t, err) defer r.Close() data := []byte("hello world!") rawWrite(t, rawW, data) w.Close() buf := make([]byte, len(data)) n, err := io.ReadFull(r, buf) assert.NoError(t, err) assert.True(t, bytes.Equal(data, buf[:n])) } func TestUserWriteRawRead(t *testing.T) { tmpdir, err := ioutil.TempDir("", "fifos") assert.NoError(t, err) defer os.RemoveAll(tmpdir) ctx, cancel := context.WithTimeout(context.Background(), 2*time.Second) defer cancel() w, err := OpenFifo(ctx, filepath.Join(tmpdir, t.Name()), syscall.O_WRONLY|syscall.O_CREAT|syscall.O_NONBLOCK, 0600) assert.NoError(t, err) defer w.Close() r, err := OpenFifo(ctx, filepath.Join(tmpdir, t.Name()), syscall.O_RDONLY|syscall.O_CREAT|syscall.O_NONBLOCK, 0600) assert.NoError(t, err) defer r.Close() rawR := makeRawConn(t, r, false) data := []byte("hello world!") n, err := w.Write(data) assert.NoError(t, err) assert.Equal(t, n, len(data)) w.Close() buf := make([]byte, len(data)) rawRead(t, rawR, buf) assert.True(t, bytes.Equal(data, buf[:n])) } func TestRawCloseError(t *testing.T) { tmpdir, err := ioutil.TempDir("", "fifos") assert.NoError(t, err) defer os.RemoveAll(tmpdir) t.Run("SyscallConnAfterClose", func(t *testing.T) { ctx, cancel := context.WithTimeout(context.Background(), 1*time.Second) defer cancel() f, err := OpenFifo(ctx, filepath.Join(tmpdir, path.Base(t.Name())), syscall.O_RDWR|syscall.O_CREAT, 0600) assert.NoError(t, err) f.Close() makeRawConn(t, f, true) }) t.Run("RawOpsAfterClose", func(t *testing.T) { ctx, cancel := context.WithTimeout(context.Background(), 1*time.Second) defer cancel() f, err := OpenFifo(ctx, filepath.Join(tmpdir, path.Base(t.Name())), syscall.O_RDWR|syscall.O_CREAT, 0600) assert.NoError(t, err) defer f.Close() raw := makeRawConn(t, f, false) f.Close() assert.Error(t, raw.Control(func(uintptr) {})) dummy := func(uintptr) bool { return true } assert.Error(t, raw.Write(dummy)) assert.Error(t, raw.Read(dummy)) }) t.Run("NonBlockRawOpsAfterClose", func(t *testing.T) { ctx, cancel := context.WithTimeout(context.Background(), 1*time.Second) defer cancel() dummy := func(uintptr) bool { return true } r, err := OpenFifo(ctx, filepath.Join(tmpdir, path.Base(t.Name())), syscall.O_RDONLY|syscall.O_CREAT|syscall.O_NONBLOCK, 0600) assert.NoError(t, err) defer r.Close() rawR := makeRawConn(t, r, false) r.Close() assert.Equal(t, ErrCtrlClosed, rawR.Control(func(uintptr) {})) assert.Equal(t, ErrReadClosed, rawR.Read(dummy)) w, err := OpenFifo(ctx, filepath.Join(tmpdir, path.Base(t.Name())), syscall.O_WRONLY|syscall.O_CREAT|syscall.O_NONBLOCK, 0600) assert.NoError(t, err) defer w.Close() rawW := makeRawConn(t, w, false) w.Close() assert.Equal(t, ErrCtrlClosed, rawW.Control(func(uintptr) {})) assert.Equal(t, ErrWriteClosed, rawW.Write(dummy)) }) } func TestRawWrongRdWrError(t *testing.T) { tmpdir, err := ioutil.TempDir("", "fifos") assert.NoError(t, err) defer os.RemoveAll(tmpdir) ctx, cancel := context.WithTimeout(context.Background(), 1*time.Second) defer cancel() dummy := func(uintptr) bool { return true } r, err := OpenFifo(ctx, filepath.Join(tmpdir, path.Base(t.Name())), syscall.O_RDONLY|syscall.O_CREAT|syscall.O_NONBLOCK, 0600) assert.NoError(t, err) defer r.Close() rawR := makeRawConn(t, r, false) assert.Equal(t, ErrWrToRDONLY, rawR.Write(dummy)) w, err := OpenFifo(ctx, filepath.Join(tmpdir, path.Base(t.Name())), syscall.O_WRONLY|syscall.O_CREAT|syscall.O_NONBLOCK, 0600) assert.NoError(t, err) defer w.Close() rawW := makeRawConn(t, w, false) assert.Equal(t, ErrRdFrmWRONLY, rawW.Read(dummy)) } func makeRawConn(t *testing.T, fifo io.ReadWriteCloser, expectError bool) syscall.RawConn { sc, ok := fifo.(syscall.Conn) assert.True(t, ok, "not a syscall.Conn") raw, err := sc.SyscallConn() if !expectError { assert.NoError(t, err) } else { assert.Error(t, err) } return raw } func rawWrite(t *testing.T, rc syscall.RawConn, data []byte) { var written int var wErr error err := rc.Write(func(fd uintptr) bool { var n int n, wErr = syscall.Write(int(fd), data[written:]) written += n if wErr != nil || n == 0 || written == len(data) { return true } return false }) assert.NoError(t, err) assert.NoError(t, wErr) assert.Equal(t, written, len(data)) } func rawRead(t *testing.T, rc syscall.RawConn, data []byte) { var ( rErr error read int ) err := rc.Read(func(fd uintptr) bool { var n int n, rErr = syscall.Read(int(fd), data[read:]) read += n if rErr != nil || n == 0 || read == len(data) { return true } return false }) assert.NoError(t, err) assert.NoError(t, rErr) assert.Equal(t, read, len(data)) } golang-github-containerd-fifo-0.0~git20190816.bda0ff6/readme.md000066400000000000000000000034761352556767700237310ustar00rootroot00000000000000### 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. ``` // OpenFifo opens a fifo. Returns io.ReadWriteCloser. // Context can be used to cancel this function until open(2) has not returned. // Accepted flags: // - syscall.O_CREAT - create new fifo if one doesn't exist // - syscall.O_RDONLY - open fifo only from reader side // - syscall.O_WRONLY - open fifo only from writer side // - syscall.O_RDWR - open fifo from both sides, never block on syscall level // - syscall.O_NONBLOCK - return io.ReadWriteCloser even if other side of the // fifo isn't open. read/write will be connected after the actual fifo is // open or after fifo is closed. func OpenFifo(ctx context.Context, fn string, flag int, perm os.FileMode) (io.ReadWriteCloser, error) // Read from a fifo to a byte array. func (f *fifo) Read(b []byte) (int, error) // Write from byte array to a fifo. func (f *fifo) Write(b []byte) (int, error) // Close the fifo. Next reads/writes will error. This method can also be used // 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.