64 lines
1.3 KiB
Go
64 lines
1.3 KiB
Go
package incrt
|
|
|
|
import (
|
|
"io"
|
|
"time"
|
|
|
|
logging "github.com/ipfs/go-log/v2"
|
|
)
|
|
|
|
var log = logging.Logger("incrt")
|
|
|
|
var now = time.Now
|
|
|
|
type ReaderDeadline interface {
|
|
Read([]byte) (int, error)
|
|
SetReadDeadline(time.Time) error
|
|
}
|
|
|
|
type incrt struct {
|
|
rd ReaderDeadline
|
|
|
|
waitPerByte time.Duration
|
|
wait time.Duration
|
|
maxWait time.Duration
|
|
}
|
|
|
|
// New creates an Incremental Reader Timeout, with minimum sustained speed of
|
|
// minSpeed bytes per second and with maximum wait of maxWait
|
|
func New(rd ReaderDeadline, minSpeed int64, maxWait time.Duration) io.Reader {
|
|
return &incrt{
|
|
rd: rd,
|
|
waitPerByte: time.Second / time.Duration(minSpeed),
|
|
wait: maxWait,
|
|
maxWait: maxWait,
|
|
}
|
|
}
|
|
|
|
func (crt *incrt) Read(buf []byte) (n int, err error) {
|
|
start := now()
|
|
err = crt.rd.SetReadDeadline(start.Add(crt.wait))
|
|
if err != nil {
|
|
return 0, err
|
|
}
|
|
|
|
defer func() {
|
|
crt.rd.SetReadDeadline(time.Time{})
|
|
if err == nil {
|
|
dur := now().Sub(start)
|
|
crt.wait -= dur
|
|
crt.wait += time.Duration(n) * crt.waitPerByte
|
|
if crt.wait < 0 {
|
|
crt.wait = 0
|
|
}
|
|
if crt.wait > crt.maxWait {
|
|
crt.wait = crt.maxWait
|
|
}
|
|
log.Warnf("max wait: %s, dur: %s, n: %d", crt.wait.String(), dur.String(), n)
|
|
}
|
|
}()
|
|
|
|
n, err = crt.rd.Read(buf)
|
|
return n, err
|
|
}
|