github.com/kubeshark/ebpf@v0.9.2/internal/epoll/poller_test.go (about)

     1  package epoll
     2  
     3  import (
     4  	"errors"
     5  	"os"
     6  	"testing"
     7  	"time"
     8  
     9  	"github.com/kubeshark/ebpf/internal/unix"
    10  )
    11  
    12  func TestPoller(t *testing.T) {
    13  	event, err := newEventFd()
    14  	if err != nil {
    15  		t.Fatal(err)
    16  	}
    17  	defer event.close()
    18  
    19  	poller, err := New()
    20  	if err != nil {
    21  		t.Fatal(err)
    22  	}
    23  	defer poller.Close()
    24  
    25  	if err := poller.Add(event.raw, 42); err != nil {
    26  		t.Fatal("Can't add fd:", err)
    27  	}
    28  
    29  	done := make(chan struct{}, 1)
    30  	read := func() {
    31  		defer func() {
    32  			done <- struct{}{}
    33  		}()
    34  
    35  		events := make([]unix.EpollEvent, 1)
    36  
    37  		n, err := poller.Wait(events)
    38  		if errors.Is(err, os.ErrClosed) {
    39  			return
    40  		}
    41  
    42  		if err != nil {
    43  			t.Error("Error from wait:", err)
    44  			return
    45  		}
    46  
    47  		if n != 1 {
    48  			t.Errorf("Got %d instead of 1 events", n)
    49  		}
    50  
    51  		if e := events[0]; e.Pad != 42 {
    52  			t.Errorf("Incorrect value in EpollEvent.Pad: %d != 42", e.Pad)
    53  		}
    54  	}
    55  
    56  	if err := event.add(1); err != nil {
    57  		t.Fatal(err)
    58  	}
    59  
    60  	go read()
    61  	select {
    62  	case <-done:
    63  	case <-time.After(time.Second):
    64  		t.Fatal("Timed out")
    65  	}
    66  
    67  	if _, err := event.read(); err != nil {
    68  		t.Fatal(err)
    69  	}
    70  
    71  	go read()
    72  	select {
    73  	case <-done:
    74  		t.Fatal("Wait doesn't block")
    75  	case <-time.After(time.Second):
    76  	}
    77  
    78  	if err := poller.Close(); err != nil {
    79  		t.Fatal("Close returns an error:", err)
    80  	}
    81  
    82  	select {
    83  	case <-done:
    84  	case <-time.After(time.Second):
    85  		t.Fatal("Close doesn't unblock Wait")
    86  	}
    87  
    88  	if err := poller.Close(); !errors.Is(err, os.ErrClosed) {
    89  		t.Fatal("Closing a second time doesn't return ErrClosed:", err)
    90  	}
    91  }