fermentord/vendor/github.com/JuulLabs-OSS/ble/handler.go

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package ble
import (
"bytes"
"context"
"io"
)
// A ReadHandler handles GATT requests.
type ReadHandler interface {
ServeRead(req Request, rsp ResponseWriter)
}
// ReadHandlerFunc is an adapter to allow the use of ordinary functions as Handlers.
type ReadHandlerFunc func(req Request, rsp ResponseWriter)
// ServeRead returns f(r, maxlen, offset).
func (f ReadHandlerFunc) ServeRead(req Request, rsp ResponseWriter) {
f(req, rsp)
}
// A WriteHandler handles GATT requests.
type WriteHandler interface {
ServeWrite(req Request, rsp ResponseWriter)
}
// WriteHandlerFunc is an adapter to allow the use of ordinary functions as Handlers.
type WriteHandlerFunc func(req Request, rsp ResponseWriter)
// ServeWrite returns f(r, maxlen, offset).
func (f WriteHandlerFunc) ServeWrite(req Request, rsp ResponseWriter) {
f(req, rsp)
}
// A NotifyHandler handles GATT requests.
type NotifyHandler interface {
ServeNotify(req Request, n Notifier)
}
// NotifyHandlerFunc is an adapter to allow the use of ordinary functions as Handlers.
type NotifyHandlerFunc func(req Request, n Notifier)
// ServeNotify returns f(r, maxlen, offset).
func (f NotifyHandlerFunc) ServeNotify(req Request, n Notifier) {
f(req, n)
}
// Request ...
type Request interface {
Conn() Conn
Data() []byte
Offset() int
}
// NewRequest returns a default implementation of Request.
func NewRequest(conn Conn, data []byte, offset int) Request {
return &request{conn: conn, data: data, offset: offset}
}
// Default implementation of request.
type request struct {
conn Conn
data []byte
offset int
}
func (r *request) Conn() Conn { return r.conn }
func (r *request) Data() []byte { return r.data }
func (r *request) Offset() int { return r.offset }
// ResponseWriter ...
type ResponseWriter interface {
// Write writes data to return as the characteristic value.
Write(b []byte) (int, error)
// Status reports the result of the request.
Status() ATTError
// SetStatus reports the result of the request.
SetStatus(status ATTError)
// Len ...
Len() int
// Cap ...
Cap() int
}
// NewResponseWriter ...
func NewResponseWriter(buf *bytes.Buffer) ResponseWriter {
return &responseWriter{buf: buf}
}
// responseWriter implements Response
type responseWriter struct {
buf *bytes.Buffer
status ATTError
}
// Status reports the result of the request.
func (r *responseWriter) Status() ATTError {
return r.status
}
// SetStatus reports the result of the request.
func (r *responseWriter) SetStatus(status ATTError) {
r.status = status
}
// Len returns length of the buffer.
// Len returns 0 if it is a dummy write response for WriteCommand.
func (r *responseWriter) Len() int {
if r.buf == nil {
return 0
}
return r.buf.Len()
}
// Cap returns capacity of the buffer.
// Cap returns 0 if it is a dummy write response for WriteCommand.
func (r *responseWriter) Cap() int {
if r.buf == nil {
return 0
}
return r.buf.Cap()
}
// Write writes data to return as the characteristic value.
// Cap returns 0 with error set to ErrReqNotSupp if it is a dummy write response for WriteCommand.
func (r *responseWriter) Write(b []byte) (int, error) {
if r.buf == nil {
return 0, ErrReqNotSupp
}
if len(b) > r.buf.Cap()-r.buf.Len() {
return 0, io.ErrShortWrite
}
return r.buf.Write(b)
}
// Notifier ...
type Notifier interface {
// Context sends data to the central.
Context() context.Context
// Write sends data to the central.
Write(b []byte) (int, error)
// Close ...
Close() error
// Cap returns the maximum number of bytes that may be sent in a single notification.
Cap() int
}
type notifier struct {
ctx context.Context
maxlen int
cancel func()
send func([]byte) (int, error)
}
// NewNotifier ...
func NewNotifier(send func([]byte) (int, error)) Notifier {
n := &notifier{}
n.ctx, n.cancel = context.WithCancel(context.Background())
n.send = send
// n.maxlen = cap
return n
}
func (n *notifier) Context() context.Context {
return n.ctx
}
func (n *notifier) Write(b []byte) (int, error) {
return n.send(b)
}
func (n *notifier) Close() error {
n.cancel()
return nil
}
func (n *notifier) Cap() int {
return n.maxlen
}