farfetched - ws_broadcast.go

     1  package main
     2  
     3  import (
     4  	"encoding/json"
     5  )
     6  
     7  const (
     8  	BroadcastUserList = -1 - iota
     9  	BroadcastUserAdd
    10  	BroadcastUserRemove
    11  	BroadcastSDP
    12  	BroadcastCancel
    13  	BroadcastAccept
    14  	BroadcastDecline
    15  )
    16  
    17  const broadcastStart = "{\"id\": -0,\"result\":"
    18  
    19  func buildBroadcast(id int, data json.RawMessage) []byte {
    20  	l := len(broadcastStart) + len(data) + 1
    21  	dat := make([]byte, l)
    22  	copy(dat, broadcastStart)
    23  	copy(dat[len(broadcastStart):], data)
    24  	id = -id
    25  	if id > 9 {
    26  		dat[6] = '-'
    27  		dat[7] = byte('0' + id/10)
    28  	}
    29  	dat[8] = byte('0' + id%10)
    30  	dat[l-1] = '}'
    31  	return dat
    32  }
    33  
    34  func Broadcast(mc *conn, id int, data json.RawMessage) {
    35  	var dat json.RawMessage
    36  	for c := range conns {
    37  		if c != mc {
    38  			if len(dat) == 0 {
    39  				dat = buildBroadcast(id, data)
    40  			}
    41  			go c.rpc.SendData(dat)
    42  		}
    43  	}
    44  }
    45