add package

[bytom/vapor.git] / vendor / github.com / hashicorp / yamux / mux.go

diff --git a/vendor/github.com/hashicorp/yamux/mux.go b/vendor/github.com/hashicorp/yamux/mux.go
new file mode 100644 (file)
index 0000000..7abc7c7
--- /dev/null
+++ b/vendor/github.com/hashicorp/yamux/mux.go
@@ -0,0 +1,87 @@
+package yamux
+
+import (
+       "fmt"
+       "io"
+       "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
+
+       // 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
+
+       // 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
+}
+
+// DefaultConfig is used to return a default configuration
+func DefaultConfig() *Config {
+       return &Config{
+               AcceptBacklog:          256,
+               EnableKeepAlive:        true,
+               KeepAliveInterval:      30 * time.Second,
+               ConnectionWriteTimeout: 10 * time.Second,
+               MaxStreamWindowSize:    initialStreamWindow,
+               LogOutput:              os.Stderr,
+       }
+}
+
+// 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.MaxStreamWindowSize < initialStreamWindow {
+               return fmt.Errorf("MaxStreamWindowSize must be larger than %d", initialStreamWindow)
+       }
+       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 io.ReadWriteCloser, config *Config) (*Session, error) {
+       if config == nil {
+               config = DefaultConfig()
+       }
+       if err := VerifyConfig(config); err != nil {
+               return nil, err
+       }
+       return newSession(config, conn, false), nil
+}
+
+// Client is used to initialize a new client-side connection.
+// There must be at most one client-side connection.
+func Client(conn io.ReadWriteCloser, config *Config) (*Session, error) {
+       if config == nil {
+               config = DefaultConfig()
+       }
+
+       if err := VerifyConfig(config); err != nil {
+               return nil, err
+       }
+       return newSession(config, conn, true), nil
+}