import (
	"log"
	"os"
	"runtime/trace"
	"syscall"
	"time"
)

func main() {
	// Create a pipe to block on.
	var p [2]int
	if err := syscall.Pipe(p[:]); err != nil {
		log.Fatalf("failed to create pipe: %v", err)
	}
	rfd, wfd := p[0], p[1]

	// Create a goroutine that blocks on the pipe.
	done := make(chan struct{})
	go func() {
		var data [1]byte
		_, err := syscall.Read(rfd, data[:])

	}
	// windows pipes are expected to use forward slashes: https://learn.microsoft.com/windows/win32/ipc/pipe-names
	// so using `url` like we do on unix gives us unclear benefits - see https://github.com/kubernetes/kubernetes/issues/78628
	// So we just construct the path from scratch.
	// Format: \\ServerName\pipe\PipeName

			outerDone <- true
		}()

		var wg sync.WaitGroup
		done := make(chan bool)

		wg.Add(1)
		go func() {
			<-done
			wg.Done()
		}()

		rp, wp, err := os.Pipe()
		if err != nil {
			log.Fatalf("failed to create pipe: %v", err)
			return
		}
		defer func() {
			rp.Close()
			wp.Close()
		}()
		wg.Add(1)
		go func() {
			var tmp [1]byte
			rp.Read(tmp[:])
			<-done
			wg.Done()

	// Create a goroutine blocked before tracing.
	wg.Add(1)
	go func() {
		<-done
		wg.Done()
	}()

	// Create a goroutine blocked in syscall before tracing.
	rp, wp, err := os.Pipe()
	if err != nil {
		log.Fatalf("failed to create pipe: %v", err)
	}
	defer func() {
		rp.Close()
		wp.Close()
	}()
	wg.Add(1)
	go func() {
		var tmp [1]byte
		rp.Read(tmp[:])
		<-done
		wg.Done()
	}()

		}
		if err = r.Close(); err != nil {
			t.Errorf("r.Close: %v", err)
		}
	}
}

// Test close on Read side during Read.
func TestPipeReadClose2(t *testing.T) {
	c := make(chan int, 1)
	r, _ := Pipe()
	go delayClose(t, r, c, pipeTest{})
	n, err := r.Read(make([]byte, 64))
	<-c
	if n != 0 || err != ErrClosedPipe {

	testenv.MustHaveGoBuild(t)
	t.Parallel()

	r, w, err := os.Pipe()
	if err != nil {
		t.Fatalf("Pipe() got err %v, want nil", err)
	}
	defer r.Close()
	defer w.Close()

	p, err := os.StartProcess(testenv.GoToolPath(t), []string{"go"}, &os.ProcAttr{
		// N.B. On Windows, StartProcess requires exactly 3 Files. Pass
		// in a dummy pipe to avoid irrelevant output on the test stdout.
		Files: []*os.File{r, w, w},
	})

	cmd := exec.Command(exe, "-test.run=ExampleSetCrashOutput_monitor")
	cmd.Env = append(os.Environ(), monitorVar+"=1")
	cmd.Stderr = os.Stderr
	cmd.Stdout = os.Stderr
	pipe, err := cmd.StdinPipe()
	if err != nil {
		log.Fatalf("StdinPipe: %v", err)
	}
	debug.SetCrashOutput(pipe.(*os.File), debug.CrashOptions{}) // (this conversion is safe)
	if err := cmd.Start(); err != nil {
		log.Fatalf("can't start monitor: %v", err)
	}

	// Race condition is because of io.PipeWriter implementation. i.e consider the following
	// sequent of operations:
	// 1) pipe.Write()
	// 2) pipe.Close()
	// Now pipe.Close() can return before the data is read on the other end of the pipe and written to the disk
	// Hence an immediate Read() on the file can return incorrect data.
	if b.canClose != nil {
		b.canClose.Wait()
	}

If you want to block when reading or writing, you must enable it:

```go
	rb := ringbuffer.New(1024).SetBlocking(true)
```

Enabling blocking will cause the ring buffer to behave like a buffered [io.Pipe](https://pkg.go.dev/io#Pipe).

Regular Reads will block until data is available, but not wait for a full buffer. 
Writes will block until there is space available and writes bigger than the buffer will wait for reads to make space.

./mc mb sitea/delissue --insecure

./mc version enable sitea/delissue --insecure

echo hello | ./mc pipe sitea/delissue/hello --insecure

./mc version suspend sitea/delissue --insecure

./mc rm sitea/delissue/hello --insecure

./mc version enable sitea/delissue --insecure

echo hello | ./mc pipe sitea/delissue/hello --insecure

./mc version suspend sitea/delissue --insecure