[Enhancement-208] Add an option to send multiple times the same files

README.md

@@ -17,6 +17,7 @@ Status"></a>
 - provides **end-to-end encryption** (using PAKE)
 - enables easy **cross-platform** transfers (Windows, Linux, Mac)
 - allows **multiple file** transfers
+- allows **multiple sequential** transfers 
 - allows **resuming transfers** that are interrupted
 - local server or port-forwarding **not needed**
 - **ipv6-first** with ipv4 fallback
@@ -134,6 +135,33 @@ The code phrase is used to establish password-authenticated key agreement ([PAKE
 
 There are a number of configurable options (see `--help`). A set of options (like custom relay, ports, and code phrase) can be set using `--remember`.
 
+### Transfer on LAN only
+
+You can transfer files using only local connections.
+
+```
+croc --local send [file(s)-or-folder]
+```
+
+### Allow multiple sequential transfers
+
+By default, after a transfer is done, the program stops.
+You can allow more than one transfer to happen (one after another) by using the `--multiple` flag, which requires a value >= 1.
+
+```
+croc send --multiple [nr-of-transfers] [file(s)-or-folder]
+```
+
+After all `[nr-of-transfers]` were done, the program will stop. To prevent keeping the program running forever if not all transfers
+possibilities are used, a timeout is set on the connection with the relay. By default, this `timeout` is set to `30 seconds`, which is 
+likely not enough. If you want to keep the connection alive for more time you can use the `--timeout` flag like this:
+
+```
+croc send --timeout [nr-of-seconds] (--multiple [nr-of-transfers]) [file(s)-or-folder]
+```
+
+*NOTE*: You can't keep the connection alive for more than `1 hour`.
+
 ### Custom code phrase
 
 You can send with your own code phrase (must be more than 6 characters).

go.mod

@@ -24,6 +24,7 @@ require (
 	github.com/OneOfOne/xxhash v1.2.8 // indirect
 	github.com/cpuguy83/go-md2man/v2 v2.0.3 // indirect
 	github.com/davecgh/go-spew v1.1.1 // indirect
+	github.com/google/uuid v1.3.1
 	github.com/magisterquis/connectproxy v0.0.0-20200725203833-3582e84f0c9b
 	github.com/mitchellh/colorstring v0.0.0-20190213212951-d06e56a500db // indirect
 	github.com/pmezard/go-difflib v1.0.0 // indirect

go.sum

@@ -18,6 +18,8 @@ github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/denisbrodbeck/machineid v1.0.1 h1:geKr9qtkB876mXguW2X6TU4ZynleN6ezuMSRhl4D7AQ=
 github.com/denisbrodbeck/machineid v1.0.1/go.mod h1:dJUwb7PTidGDeYyUBmXZ2GphQBbjJCrnectwCyxcUSI=
+github.com/google/uuid v1.3.1 h1:KjJaJ9iWZ3jOFZIf1Lqf4laDRCasjl0BCmnEGxkdLb4=
+github.com/google/uuid v1.3.1/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
 github.com/k0kubun/go-ansi v0.0.0-20180517002512-3bf9e2903213/go.mod h1:vNUNkEQ1e29fT/6vq2aBdFsgNPmy8qMdSay1npru+Sw=
 github.com/kalafut/imohash v1.0.2 h1:j/cUPa15YvXv7abJlM+kdJIycbBMpmO7WqhPl4YB76I=
 github.com/kalafut/imohash v1.0.2/go.mod h1:PjHBF0vpo1q7zMqiTn0qwSTQU2wDn5QIe8S8sFQuZS8=

src/cli/cli.go

@@ -44,7 +44,7 @@ func Run() (err error) {
 	app.UsageText = `Send a file:
       croc send file.txt
 
-      -git to respect your .gitignore
+	-git to respect your .gitignore
    Send multiple files:
       croc send file1.txt file2.txt file3.txt
     or
@@ -66,6 +66,8 @@ func Run() (err error) {
 			ArgsUsage:   "[filename(s) or folder]",
 			Flags: []cli.Flag{
 				&cli.BoolFlag{Name: "zip", Usage: "zip folder before sending"},
+				&cli.IntFlag{Name: "timelimit", Value: 30, Usage: "timelimit in secods for sender to allow all transfers"},
+				&cli.IntFlag{Name: "multiple", Value: 1, Usage: "maximum number of transfers"},
 				&cli.StringFlag{Name: "code", Aliases: []string{"c"}, Usage: "codephrase used to connect to relay"},
 				&cli.StringFlag{Name: "hash", Value: "xxhash", Usage: "hash algorithm (xxhash, imohash, md5)"},
 				&cli.StringFlag{Name: "text", Aliases: []string{"t"}, Usage: "send some text"},
@@ -181,6 +183,8 @@ func send(c *cli.Context) (err error) {
 	crocOptions := croc.Options{
 		SharedSecret:   c.String("code"),
 		IsSender:       true,
+		TimeLimit:      c.Int("timelimit"),
+		MaxTransfers:   c.Int("multiple"),
 		Debug:          c.Bool("debug"),
 		NoPrompt:       c.Bool("yes"),
 		RelayAddress:   c.String("relay"),
@@ -202,11 +206,30 @@ func send(c *cli.Context) (err error) {
 		ZipFolder:      c.Bool("zip"),
 		GitIgnore:      c.Bool("git"),
 	}
+
+	if crocOptions.TimeLimit <= 0 {
+		fmt.Println("timelimit must be greater than 0. Defaulting to 30 seconds.")
+		crocOptions.TimeLimit = 30
+	} else if crocOptions.TimeLimit > 3600 {
+		fmt.Println("timelimit must be less than 3600. Defaulting to 30 seconds.")
+		crocOptions.TimeLimit = 30
+	}
+
+	if crocOptions.MaxTransfers <= 0 {
+		fmt.Println("multiple must be greater than 0. Defaulting to 1 transfers.")
+		crocOptions.MaxTransfers = 1
+	} else if crocOptions.MaxTransfers > 1 {
+		fmt.Println("Allowing multiple transfers.")
+		fmt.Println("The connection will stay open until all transfers are complete, or the timelimit is reached.")
+		fmt.Printf("The current timelimit is %d seconds.\n", crocOptions.TimeLimit)
+	}
+
 	if crocOptions.RelayAddress != models.DEFAULT_RELAY {
 		crocOptions.RelayAddress6 = ""
 	} else if crocOptions.RelayAddress6 != models.DEFAULT_RELAY6 {
 		crocOptions.RelayAddress = ""
 	}
+
 	b, errOpen := os.ReadFile(getConfigFile())
 	if errOpen == nil && !c.Bool("remember") {
 		var rememberedOptions croc.Options

src/comm/comm.go

@@ -10,6 +10,7 @@ import (
 	"strings"
 	"time"
 
+	"github.com/google/uuid"
 	"github.com/magisterquis/connectproxy"
 	"github.com/schollz/croc/v9/src/utils"
 	log "github.com/schollz/logger"
@@ -23,6 +24,7 @@ var MAGIC_BYTES = []byte("croc")
 
 // Comm is some basic TCP communication
 type Comm struct {
+	id         string
 	connection net.Conn
 }
 
@@ -100,6 +102,7 @@ func New(c net.Conn) *Comm {
 		log.Errorf("error setting write deadline: %v", err)
 	}
 	comm := new(Comm)
+	comm.id = uuid.New().String()
 	comm.connection = c
 	return comm
 }
@@ -109,6 +112,10 @@ func (c *Comm) Connection() net.Conn {
 	return c.connection
 }
 
+func (c *Comm) ID() string {
+	return c.id
+}
+
 // Close closes the connection
 func (c *Comm) Close() {
 	if err := c.connection.Close(); err != nil {

src/comm/comm_test.go

@@ -51,6 +51,7 @@ func TestComm(t *testing.T) {
 	time.Sleep(300 * time.Millisecond)
 	a, err := NewConnection("127.0.0.1:"+port, 10*time.Minute)
 	assert.Nil(t, err)
+	assert.NotNil(t, a.id)
 	data, err := a.Receive()
 	assert.Equal(t, []byte("hello, world"), data)
 	assert.Nil(t, err)