// send is run in a separate goroutine. It's used
// to ensure clear interleaving of frames and to
// provide assurances of priority and structure.
func (c *Conn) send() {
// Catch any panics.
defer func() {
if v := recover(); v != nil {
if !c.Closed() {
log.Printf("Encountered send error: %v (%[1]T)\n", v)
}
}
}()
// Enter the processing loop.
i := 1
for {
// Once per 5 frames, pick randomly.
var frame common.Frame
if i == 0 { // Ignore priority.
frame = c.selectFrameToSend(false)
} else { // Normal selection.
frame = c.selectFrameToSend(true)
}
i++
if i >= 5 {
i = 0
}
if frame == nil {
c.Close()
return
}
// Compress any name/value header blocks.
err := frame.Compress(c.compressor)
if err != nil {
log.Printf("Error in compression: %v (%T).\n", err, frame)
return
}
debug.Printf("Sending %s:\n", frame.Name())
debug.Println(frame)
// Leave the specifics of writing to the
// connection up to the frame.
c.refreshWriteTimeout()
_, err = frame.WriteTo(c.conn)
if err != nil {
c.handleReadWriteError(err)
return
}
}
}
// send is run in a separate goroutine. It's used
// to ensure clear interleaving of frames and to
// provide assurances of priority and structure.
func (c *Conn) send() {
// Catch any panics.
defer func() {
if v := recover(); v != nil {
if !c.Closed() {
log.Printf("Encountered send error: %v (%[1]T)\n", v)
}
}
}()
for i := 1; ; i++ {
if i >= 5 {
i = 0 // Once per 5 frames, pick randomly.
}
var frame common.Frame
if i == 0 { // Ignore priority.
frame = c.selectFrameToSend(false)
} else { // Normal selection.
frame = c.selectFrameToSend(true)
}
if frame == nil {
c.Close()
return
}
// Process connection-level flow control.
if c.Subversion > 0 {
c.connectionWindowLock.Lock()
if frame, ok := frame.(*frames.DATA); ok {
size := int64(len(frame.Data))
constrained := false
sending := size
if sending > c.connectionWindowSize {
sending = c.connectionWindowSize
constrained = true
}
if sending < 0 {
sending = 0
}
c.connectionWindowSize -= sending
if constrained {
// Chop off what we can send now.
partial := new(frames.DATA)
partial.Flags = frame.Flags
partial.StreamID = frame.StreamID
partial.Data = make([]byte, int(sending))
copy(partial.Data, frame.Data[:sending])
frame.Data = frame.Data[sending:]
// Buffer this frame and try again.
if c.dataBuffer == nil {
c.dataBuffer = []*frames.DATA{frame}
} else {
buffer := make([]*frames.DATA, 1, len(c.dataBuffer)+1)
buffer[0] = frame
buffer = append(buffer, c.dataBuffer...)
c.dataBuffer = buffer
}
frame = partial
}
}
c.connectionWindowLock.Unlock()
}
// Compress any name/value header blocks.
err := frame.Compress(c.compressor)
if err != nil {
log.Printf("Error in compression: %v (type %T).\n", err, frame)
c.Close()
return
}
debug.Printf("Sending %s:\n", frame.Name())
debug.Println(frame)
// Leave the specifics of writing to the
// connection up to the frame.
c.refreshWriteTimeout()
if _, err = frame.WriteTo(c.conn); err != nil {
c.handleReadWriteError(err)
return
}
}
}