status-go/vendor/github.com/libp2p/go-yamux/v3/mux.go

134 lines
4.0 KiB
Go

package yamux
import (
"errors"
"fmt"
"io"
"net"
"os"
"time"
)
// Config is used to tune the Yamux session
type Config struct {
// AcceptBacklog is used to limit how many streams may be
// waiting an accept.
AcceptBacklog int
// PingBacklog is used to limit how many ping acks we can queue.
PingBacklog int
// EnableKeepalive is used to do a period keep alive
// messages using a ping.
EnableKeepAlive bool
// KeepAliveInterval is how often to perform the keep alive
KeepAliveInterval time.Duration
// ConnectionWriteTimeout is meant to be a "safety valve" timeout after
// we which will suspect a problem with the underlying connection and
// close it. This is only applied to writes, where's there's generally
// an expectation that things will move along quickly.
ConnectionWriteTimeout time.Duration
// MaxIncomingStreams is maximum number of concurrent incoming streams
// that we accept. If the peer tries to open more streams, those will be
// reset immediately.
MaxIncomingStreams uint32
// InitialStreamWindowSize is used to control the initial
// window size that we allow for a stream.
InitialStreamWindowSize uint32
// MaxStreamWindowSize is used to control the maximum
// window size that we allow for a stream.
MaxStreamWindowSize uint32
// LogOutput is used to control the log destination
LogOutput io.Writer
// ReadBufSize controls the size of the read buffer.
//
// Set to 0 to disable it.
ReadBufSize int
// WriteCoalesceDelay is the maximum amount of time we'll delay
// coalescing a packet before sending it. This should be on the order of
// micro-milliseconds.
WriteCoalesceDelay time.Duration
// MaxMessageSize is the maximum size of a message that we'll send on a
// stream. This ensures that a single stream doesn't hog a connection.
MaxMessageSize uint32
}
// DefaultConfig is used to return a default configuration
func DefaultConfig() *Config {
return &Config{
AcceptBacklog: 256,
PingBacklog: 32,
EnableKeepAlive: true,
KeepAliveInterval: 30 * time.Second,
ConnectionWriteTimeout: 10 * time.Second,
MaxIncomingStreams: 1000,
InitialStreamWindowSize: initialStreamWindow,
MaxStreamWindowSize: maxStreamWindow,
LogOutput: os.Stderr,
ReadBufSize: 4096,
MaxMessageSize: 64 * 1024,
WriteCoalesceDelay: 100 * time.Microsecond,
}
}
// VerifyConfig is used to verify the sanity of configuration
func VerifyConfig(config *Config) error {
if config.AcceptBacklog <= 0 {
return fmt.Errorf("backlog must be positive")
}
if config.KeepAliveInterval == 0 {
return fmt.Errorf("keep-alive interval must be positive")
}
if config.InitialStreamWindowSize < initialStreamWindow {
return errors.New("InitialStreamWindowSize must be larger or equal 256 kB")
}
if config.MaxStreamWindowSize < config.InitialStreamWindowSize {
return errors.New("MaxStreamWindowSize must be larger than the InitialStreamWindowSize")
}
if config.MaxMessageSize < 1024 {
return fmt.Errorf("MaxMessageSize must be greater than a kilobyte")
}
if config.WriteCoalesceDelay < 0 {
return fmt.Errorf("WriteCoalesceDelay must be >= 0")
}
if config.PingBacklog < 1 {
return fmt.Errorf("PingBacklog must be > 0")
}
return nil
}
// Server is used to initialize a new server-side connection.
// There must be at most one server-side connection. If a nil config is
// provided, the DefaultConfiguration will be used.
func Server(conn net.Conn, config *Config, mm MemoryManager) (*Session, error) {
if config == nil {
config = DefaultConfig()
}
if err := VerifyConfig(config); err != nil {
return nil, err
}
return newSession(config, conn, false, config.ReadBufSize, mm), nil
}
// Client is used to initialize a new client-side connection.
// There must be at most one client-side connection.
func Client(conn net.Conn, config *Config, mm MemoryManager) (*Session, error) {
if config == nil {
config = DefaultConfig()
}
if err := VerifyConfig(config); err != nil {
return nil, err
}
return newSession(config, conn, true, config.ReadBufSize, mm), nil
}