diff --git a/dfu.go b/dfu.go index e054ad3..5a7365f 100644 --- a/dfu.go +++ b/dfu.go @@ -6,7 +6,6 @@ import ( "encoding/binary" "encoding/json" "errors" - "io" "io/fs" "io/ioutil" "os" @@ -191,6 +190,23 @@ func (dfu *DFU) sendProgress() { } } +// bufferPropsCh resends all messages on in to a new channel that is buffered with 5 elements +func bufferPropsCh(in chan *bluez.PropertyChanged) chan *bluez.PropertyChanged { + // Create new buffered channel + out := make(chan *bluez.PropertyChanged, 5) + go func() { + // Close channel when underlying channel closed + defer close(out) + // For every property change on in + for prop := range in { + // Write to out + out <- prop + } + }() + // Return new buffered channel + return out +} + // Start DFU process func (dfu *DFU) Start() error { if dfu.progress == nil { @@ -209,10 +225,12 @@ func (dfu *DFU) Start() error { } // Watch for property changes on control point - dfu.ctrlRespCh, err = dfu.ctrlPointChar.WatchProperties() + unbufferedCh, err := dfu.ctrlPointChar.WatchProperties() if err != nil { return err } + // Buffer properties channel so no changes are missed + dfu.ctrlRespCh = bufferPropsCh(unbufferedCh) // Run step one err = dfu.stepOne() @@ -279,24 +297,42 @@ func (dfu *DFU) Start() error { return nil } +// Reset reverts all values back to default to prepare for +// the next DFU. +func (dfu *DFU) Reset() { + dfu.bytesRecvd = 0 + dfu.bytesSent = 0 + dfu.fwSize = 0 + dfu.fwSendDone = false + dfu.fwImage = nil + dfu.initPacket = nil + dfu.ctrlRespCh = nil + dfu.progress = nil +} + // on waits for the given command to be received on // the control point characteristic, then runs the callback. func (dfu *DFU) on(cmd []byte, onCmdCb func(data []byte) error) error { - select { - case propChanged := <-dfu.ctrlRespCh: - if propChanged.Name != "Value" { + // Use for loop in case of invalid property + for { + select { + case propChanged := <-dfu.ctrlRespCh: + // If property was invalid + if propChanged.Name != "Value" { + // Keep waiting + continue + } + // Assert propery value as byte slice + data := propChanged.Value.([]byte) + // If command has prefix of given command + if bytes.HasPrefix(data, cmd) { + // Return callback with data after command + return onCmdCb(data[len(cmd):]) + } return ErrDFUInvalidResponse + case <-time.After(50 * time.Second): + return ErrDFUTimeout } - // Assert propery value as byte slice - data := propChanged.Value.([]byte) - // If command has prefix of given command - if bytes.HasPrefix(data, cmd) { - // Return callback with data after command - return onCmdCb(data[len(cmd):]) - } - return ErrDFUInvalidResponse - case <-time.After(50 * time.Second): - return ErrDFUTimeout } } @@ -346,7 +382,13 @@ func (dfu *DFU) stepSeven() error { // While send is not done for !dfu.fwSendDone { for i := 0; i < DFUPktRecvInterval; i++ { - amtLeft := int(dfu.fwSize) - dfu.bytesSent + amtLeft := dfu.fwSize - int64(dfu.bytesSent) + // If no bytes left to send, end transfer + if amtLeft == 0 { + dfu.sendProgress() + dfu.fwSendDone = true + return nil + } var segment []byte // If amount left is less than segment size if amtLeft < DFUSegmentSize { @@ -357,13 +399,8 @@ func (dfu *DFU) stepSeven() error { segment = make([]byte, DFUSegmentSize) } // Write firmware image into slice - n, err := dfu.fwImage.Read(segment) - // If EOF, send is done - if err == io.EOF { - dfu.sendProgress() - dfu.fwSendDone = true - return nil - } else if err != nil { + _, err := dfu.fwImage.Read(segment) + if err != nil { return err } // Write segment to packet characteristic @@ -372,7 +409,7 @@ func (dfu *DFU) stepSeven() error { return err } // Increment bytes sent by amount read - dfu.bytesSent += n + dfu.bytesSent += len(segment) } // On 0x11, verify packet receipt size err := dfu.on(DFUNotifPktRecvd, func(data []byte) error {