blob: a429edba1c1e2b6786af1bf49fd021fca36c126f [file] [log] [blame]
//go:build go1.12
// +build go1.12
package pty
import (
"context"
"errors"
"os"
"runtime"
"sync"
"testing"
"time"
)
const (
errMarker byte = 0xEE
timeout = time.Second
)
//nolint:gochecknoglobals // Expected global lock to avoid potential race on (*os.File).Fd().
var glTestFdLock sync.Mutex
// Check that SetDeadline() works for ptmx.
// Outstanding Read() calls must be interrupted by deadline.
//
// https://github.com/creack/pty/issues/162
//
//nolint:paralleltest // Potential in (*os.File).Fd().
func TestReadDeadline(t *testing.T) {
ptmx, success := prepare(t)
if err := ptmx.SetDeadline(time.Now().Add(timeout / 10)); err != nil {
if errors.Is(err, os.ErrNoDeadline) {
t.Skipf("Deadline is not supported on %s/%s.", runtime.GOOS, runtime.GOARCH)
} else {
t.Fatalf("Error: set deadline: %s.", err)
}
}
buf := make([]byte, 1)
n, err := ptmx.Read(buf)
success()
if err != nil && !errors.Is(err, os.ErrDeadlineExceeded) {
t.Fatalf("Unexpected read error: %s.", err)
}
if n != 0 && buf[0] != errMarker {
t.Errorf("Received unexpected data from pmtx (%d bytes): 0x%X; err=%v.", n, buf, err)
}
}
// Check that ptmx.Close() interrupts outstanding ptmx.Read() calls.
//
// https://github.com/creack/pty/issues/114
// https://github.com/creack/pty/issues/88
//
//nolint:paralleltest // Potential in (*os.File).Fd().
func TestReadClose(t *testing.T) {
ptmx, success := prepare(t)
go func() {
time.Sleep(timeout / 10)
if err := ptmx.Close(); err != nil {
t.Errorf("Failed to close ptmx: %s.", err)
}
}()
buf := make([]byte, 1)
n, err := ptmx.Read(buf)
success()
if err != nil && !errors.Is(err, os.ErrClosed) {
t.Fatalf("Unexpected read error: %s.", err)
}
if n != 0 && buf[0] != errMarker {
t.Errorf("Received unexpected data from pmtx (%d bytes): 0x%X; err=%v.", n, buf, err)
}
}
// Open pty and setup watchdogs for graceful and not so graceful failure modes.
func prepare(t *testing.T) (ptmx *os.File, done func()) {
t.Helper()
if runtime.GOOS == "darwin" {
t.Log("creack/pty uses blocking i/o on darwin intentionally:")
t.Log("> https://github.com/creack/pty/issues/52")
t.Log("> https://github.com/creack/pty/pull/53")
t.Log("> https://github.com/golang/go/issues/22099")
t.SkipNow()
}
// Due to data race potential in (*os.File).Fd()
// we should never run these two tests in parallel.
glTestFdLock.Lock()
t.Cleanup(glTestFdLock.Unlock)
ptmx, pts, err := Open()
if err != nil {
t.Fatalf("Error: open: %s.\n", err)
}
t.Cleanup(func() { _ = ptmx.Close() })
t.Cleanup(func() { _ = pts.Close() })
ctx, done := context.WithCancel(context.Background())
t.Cleanup(done)
go func() {
select {
case <-ctx.Done():
// ptmx.Read() did not block forever, yay!
case <-time.After(timeout):
if _, err := pts.Write([]byte{errMarker}); err != nil { // Unblock ptmx.Read().
t.Errorf("Failed to write to pts: %s.", err)
}
t.Error("ptmx.Read() was not unblocked.")
done() // Cancel panic().
}
}()
go func() {
select {
case <-ctx.Done():
// Test has either failed or succeeded; it definitely did not hang.
case <-time.After(timeout * 10 / 9): // Timeout + 11%.
panic("ptmx.Read() was not unblocked; avoid hanging forever.") // Just in case.
}
}()
return ptmx, done
}