rearrange block communication

src/recipient/recipient.go

@@ -51,6 +51,8 @@ func receive(forceSend int, serverAddress string, tcpPorts []string, isLocal boo
 	var transferTime time.Duration
 	var hash256 []byte
 	var otherIP string
+	var progressFile string
+	var resumeFile bool
 	var tcpConnections []comm.Comm
 	dataChan := make(chan []byte, 1024*1024)
 	blocks := []string{}
@@ -132,17 +134,7 @@ func receive(forceSend int, serverAddress string, tcpPorts []string, isLocal boo
 			}
 			log.Debugf("%x\n", sessionKey)
 
-			// append the previous blocks if there was progress previously
-			file, errCrocProgress := os.Open("croc-progress")
-			if errCrocProgress == nil {
-				scanner := bufio.NewScanner(file)
-				for scanner.Scan() {
-					blocks = append(blocks, strings.TrimSpace(scanner.Text()))
-				}
-				file.Close()
-			}
-			blocksBytes, _ := json.Marshal(blocks)
-			c.WriteMessage(websocket.BinaryMessage, append([]byte("ready"), blocksBytes...))
+			c.WriteMessage(websocket.BinaryMessage, []byte("ready"))
 		case 3:
 			spin.Stop()
 
@@ -164,9 +156,14 @@ func receive(forceSend int, serverAddress string, tcpPorts []string, isLocal boo
 			log.Debugf("got file stats: %+v", fstats)
 
 			// prompt user if its okay to receive file
+			progressFile = fmt.Sprintf("%s.progress", fstats.SentName)
 			overwritingOrReceiving := "Receiving"
-			if utils.Exists(fstats.Name) {
+			if utils.Exists(fstats.Name) || utils.Exists(fstats.SentName) {
 				overwritingOrReceiving = "Overwriting"
+				if utils.Exists(progressFile) && !useWebsockets {
+					overwritingOrReceiving = "Resume receiving"
+					resumeFile = true
+				}
 			}
 			fileOrFolder := "file"
 			if fstats.IsDir {
@@ -220,6 +217,26 @@ func receive(forceSend int, serverAddress string, tcpPorts []string, isLocal boo
 					return err
 				}
 			}
+
+			// append the previous blocks if there was progress previously
+			if resumeFile {
+				file, _ := os.Open(progressFile)
+				scanner := bufio.NewScanner(file)
+				for scanner.Scan() {
+					blocks = append(blocks, strings.TrimSpace(scanner.Text()))
+				}
+				file.Close()
+			}
+			blocksBytes, _ := json.Marshal(blocks)
+
+			blockSize := 0
+			if useWebsockets {
+				blockSize = models.WEBSOCKET_BUFFER_SIZE / 8
+			} else {
+				blockSize = models.TCP_BUFFER_SIZE / 2
+			}
+
+			// start the ui for pgoress
 			bytesWritten := 0
 			fmt.Fprintf(os.Stderr, "\nReceiving (<-%s)...\n", otherIP)
 			bar := progressbar.NewOptions(
@@ -228,15 +245,24 @@ func receive(forceSend int, serverAddress string, tcpPorts []string, isLocal boo
 				progressbar.OptionSetBytes(int(fstats.Size)),
 				progressbar.OptionSetWriter(os.Stderr),
 			)
+			bar.Add((len(blocks) * blockSize))
 			finished := make(chan bool)
 
 			go func(finished chan bool, dataChan chan []byte) (err error) {
-				os.Remove("croc-progress2")
-				fProgress, errCreate := os.Create("croc-progress2")
-				if errCreate != nil {
-					panic(errCreate)
+				// remove previous progress
+				var fProgress *os.File
+				var progressErr error
+				if resumeFile {
+					fProgress, progressErr = os.OpenFile(progressFile, os.O_APPEND, 0644)
+				} else {
+					os.Remove(progressFile)
+					fProgress, progressErr = os.Create(progressFile)
+				}
+				if progressErr != nil {
+					panic(progressErr)
 				}
 				defer fProgress.Close()
+
 				blocksWritten := 0.0
 				blocksToWrite := float64(fstats.Size)
 				if useWebsockets {
@@ -305,7 +331,8 @@ func receive(forceSend int, serverAddress string, tcpPorts []string, isLocal boo
 			}(finished, dataChan)
 
 			log.Debug("telling sender i'm ready")
-			c.WriteMessage(websocket.BinaryMessage, []byte("ready"))
+			c.WriteMessage(websocket.BinaryMessage, append([]byte("ready"), blocksBytes...))
+
 			startTime := time.Now()
 			if useWebsockets {
 				for {
@@ -426,6 +453,7 @@ func receive(forceSend int, serverAddress string, tcpPorts []string, isLocal boo
 						fstats.Name = "stdout"
 					}
 					fmt.Fprintf(os.Stderr, "\nReceived %s written to %s (%2.1f %s)\n", folderOrFile, fstats.Name, transferRate, transferType)
+					os.Remove(progressFile)
 				}
 				return err
 			} else {
@@ -435,7 +463,6 @@ func receive(forceSend int, serverAddress string, tcpPorts []string, isLocal boo
 				}
 				return errors.New("file corrupted")
 			}
-
 		default:
 			return fmt.Errorf("unknown step")
 		}

src/sender/sender.go

@@ -199,14 +199,38 @@ func send(forceSend int, serverAddress string, tcpPorts []string, isLocal bool,
 			if !bytes.HasPrefix(message, []byte("ready")) {
 				return errors.New("recipient refused file")
 			}
+
+			err = <-fileReady // block until file is ready
+			if err != nil {
+				return err
+			}
+			fstatsBytes, err := json.Marshal(fstats)
+			if err != nil {
+				return err
+			}
+
+			// encrypt the file meta data
+			enc := crypt.Encrypt(fstatsBytes, sessionKey)
+			// send the file meta data
+			c.WriteMessage(websocket.BinaryMessage, enc.Bytes())
+		case 4:
+			spin.Stop()
+
+			log.Debugf("[%d] recipient declares readiness for file data", step)
+			if !bytes.HasPrefix(message, []byte("ready")) {
+				return errors.New("recipient refused file")
+			}
+
 			// determine if any blocks were sent to skip
 			var blocks []string
 			errBlocks := json.Unmarshal(message[5:], &blocks)
 			if errBlocks == nil {
 				log.Debugf("found blocks: %+v", blocks)
 				for _, block := range blocks {
-					blockInt64, _ := strconv.Atoi(block)
-					blocksToSkip[int64(blockInt64)] = struct{}{}
+					blockInt64, errBlock := strconv.Atoi(block)
+					if errBlock == nil {
+						blocksToSkip[int64(blockInt64)] = struct{}{}
+					}
 				}
 			}
 
@@ -298,27 +322,6 @@ func send(forceSend int, serverAddress string, tcpPorts []string, isLocal bool,
 				}
 			}(dataChan)
 
-			err = <-fileReady // block until file is ready
-			if err != nil {
-				return err
-			}
-			fstatsBytes, err := json.Marshal(fstats)
-			if err != nil {
-				return err
-			}
-
-			// encrypt the file meta data
-			enc := crypt.Encrypt(fstatsBytes, sessionKey)
-			// send the file meta data
-			c.WriteMessage(websocket.BinaryMessage, enc.Bytes())
-		case 4:
-			spin.Stop()
-
-			log.Debugf("[%d] recipient declares readiness for file data", step)
-			if !bytes.Equal(message, []byte("ready")) {
-				return errors.New("recipient refused file")
-			}
-
 			// connect to TCP to receive file
 			if !useWebsockets {
 				log.Debugf("connecting to server")

src/zipper/zip.go

@@ -4,7 +4,6 @@ import (
 	"archive/zip"
 	"compress/flate"
 	"io"
-	"io/ioutil"
 	"os"
 	"path/filepath"
 	"strings"
@@ -97,7 +96,7 @@ func ZipFile(fname string, compress bool) (writtenFilename string, err error) {
 		return
 	}
 	log.Debugf("current directory: %s", curdir)
-	newfile, err := ioutil.TempFile(curdir, filename+".")
+	newfile, err := os.Create(fname + ".zip")
 	if err != nil {
 		log.Error(err)
 		return