nbpipe_test.go

Documentation: runtime

     1  // Copyright 2019 The Go Authors. All rights reserved.
     2  // Use of this source code is governed by a BSD-style
     3  // license that can be found in the LICENSE file.
     4  
     5  //go:build aix || darwin || dragonfly || freebsd || linux || netbsd || openbsd || solaris
     6  // +build aix darwin dragonfly freebsd linux netbsd openbsd solaris
     7  
     8  package runtime_test
     9  
    10  import (
    11  	"runtime"
    12  	"syscall"
    13  	"testing"
    14  	"unsafe"
    15  )
    16  
    17  func TestNonblockingPipe(t *testing.T) {
    18  	t.Parallel()
    19  
    20  	// NonblockingPipe is the test name for nonblockingPipe.
    21  	r, w, errno := runtime.NonblockingPipe()
    22  	if errno != 0 {
    23  		t.Fatal(syscall.Errno(errno))
    24  	}
    25  	defer func() {
    26  		runtime.Close(r)
    27  		runtime.Close(w)
    28  	}()
    29  
    30  	checkIsPipe(t, r, w)
    31  	checkNonblocking(t, r, "reader")
    32  	checkCloseonexec(t, r, "reader")
    33  	checkNonblocking(t, w, "writer")
    34  	checkCloseonexec(t, w, "writer")
    35  }
    36  
    37  func checkIsPipe(t *testing.T, r, w int32) {
    38  	bw := byte(42)
    39  	if n := runtime.Write(uintptr(w), unsafe.Pointer(&bw), 1); n != 1 {
    40  		t.Fatalf("Write(w, &b, 1) == %d, expected 1", n)
    41  	}
    42  	var br byte
    43  	if n := runtime.Read(r, unsafe.Pointer(&br), 1); n != 1 {
    44  		t.Fatalf("Read(r, &b, 1) == %d, expected 1", n)
    45  	}
    46  	if br != bw {
    47  		t.Errorf("pipe read %d, expected %d", br, bw)
    48  	}
    49  }
    50  
    51  func checkNonblocking(t *testing.T, fd int32, name string) {
    52  	t.Helper()
    53  	flags, errno := fcntl(uintptr(fd), syscall.F_GETFL, 0)
    54  	if errno != 0 {
    55  		t.Errorf("fcntl(%s, F_GETFL) failed: %v", name, syscall.Errno(errno))
    56  	} else if flags&syscall.O_NONBLOCK == 0 {
    57  		t.Errorf("O_NONBLOCK not set in %s flags %#x", name, flags)
    58  	}
    59  }
    60  
    61  func checkCloseonexec(t *testing.T, fd int32, name string) {
    62  	t.Helper()
    63  	flags, errno := fcntl(uintptr(fd), syscall.F_GETFD, 0)
    64  	if errno != 0 {
    65  		t.Errorf("fcntl(%s, F_GETFD) failed: %v", name, syscall.Errno(errno))
    66  	} else if flags&syscall.FD_CLOEXEC == 0 {
    67  		t.Errorf("FD_CLOEXEC not set in %s flags %#x", name, flags)
    68  	}
    69  }
    70  
    71  func TestSetNonblock(t *testing.T) {
    72  	t.Parallel()
    73  
    74  	r, w, errno := runtime.Pipe()
    75  	if errno != 0 {
    76  		t.Fatal(syscall.Errno(errno))
    77  	}
    78  	defer func() {
    79  		runtime.Close(r)
    80  		runtime.Close(w)
    81  	}()
    82  
    83  	checkIsPipe(t, r, w)
    84  
    85  	runtime.SetNonblock(r)
    86  	runtime.SetNonblock(w)
    87  	checkNonblocking(t, r, "reader")
    88  	checkNonblocking(t, w, "writer")
    89  
    90  	runtime.Closeonexec(r)
    91  	runtime.Closeonexec(w)
    92  	checkCloseonexec(t, r, "reader")
    93  	checkCloseonexec(t, w, "writer")
    94  }
    95
View as plain text