github.com/lovishpuri/go-40569/src@v0.0.0-20230519171745-f8623e7c56cf/os/rawconn_test.go (about)

     1  // Copyright 2018 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  // Test use of raw connections.
     6  //
     7  //go:build !plan9 && !js && !wasip1
     8  
     9  package os_test
    10  
    11  import (
    12  	"os"
    13  	"syscall"
    14  	"testing"
    15  )
    16  
    17  func TestRawConnReadWrite(t *testing.T) {
    18  	t.Parallel()
    19  
    20  	r, w, err := os.Pipe()
    21  	if err != nil {
    22  		t.Fatal(err)
    23  	}
    24  	defer r.Close()
    25  	defer w.Close()
    26  
    27  	rconn, err := r.SyscallConn()
    28  	if err != nil {
    29  		t.Fatal(err)
    30  	}
    31  	wconn, err := w.SyscallConn()
    32  	if err != nil {
    33  		t.Fatal(err)
    34  	}
    35  
    36  	var operr error
    37  	err = wconn.Write(func(s uintptr) bool {
    38  		_, operr = syscall.Write(syscallDescriptor(s), []byte{'b'})
    39  		return operr != syscall.EAGAIN
    40  	})
    41  	if err != nil {
    42  		t.Fatal(err)
    43  	}
    44  	if operr != nil {
    45  		t.Fatal(err)
    46  	}
    47  
    48  	var n int
    49  	buf := make([]byte, 1)
    50  	err = rconn.Read(func(s uintptr) bool {
    51  		n, operr = syscall.Read(syscallDescriptor(s), buf)
    52  		return operr != syscall.EAGAIN
    53  	})
    54  	if err != nil {
    55  		t.Fatal(err)
    56  	}
    57  	if operr != nil {
    58  		t.Fatal(operr)
    59  	}
    60  	if n != 1 {
    61  		t.Errorf("read %d bytes, expected 1", n)
    62  	}
    63  	if buf[0] != 'b' {
    64  		t.Errorf("read %q, expected %q", buf, "b")
    65  	}
    66  }