From d4517bc26f3c0f917c3070f173d334cb0bdfa5aa Mon Sep 17 00:00:00 2001
From: Rolf Neugebauer <rolf.neugebauer@docker.com>
Date: Wed, 8 Nov 2017 10:58:42 +0000
Subject: [PATCH] tool: Move the code for parsing published ports to utils.go

This code will soon be shared by other backends.

While at it, also rename the type to PublishPort (from publishPorts)
as it is just one Port and the function from splitPublish() to
NewPublishPort() as this seems more go like.

Signed-off-by: Rolf Neugebauer <rolf.neugebauer@docker.com>
---
 src/cmd/linuxkit/run_qemu.go | 54 ++----------------------------------
 src/cmd/linuxkit/util.go     | 52 ++++++++++++++++++++++++++++++++++
 2 files changed, 54 insertions(+), 52 deletions(-)

diff --git a/src/cmd/linuxkit/run_qemu.go b/src/cmd/linuxkit/run_qemu.go
index 8dec12943..e1a6cd4ab 100644
--- a/src/cmd/linuxkit/run_qemu.go
+++ b/src/cmd/linuxkit/run_qemu.go
@@ -620,12 +620,6 @@ func discoverBackend(config QemuConfig) QemuConfig {
 
 type multipleFlag []string
 
-type publishedPorts struct {
-	guest    int
-	host     int
-	protocol string
-}
-
 func (f *multipleFlag) String() string {
 	return "A multiple flag is a type of flag that can be repeated any number of times"
 }
@@ -635,57 +629,13 @@ func (f *multipleFlag) Set(value string) error {
 	return nil
 }
 
-func splitPublish(publish string) (publishedPorts, error) {
-	p := publishedPorts{}
-	slice := strings.Split(publish, ":")
-
-	if len(slice) < 2 {
-		return p, fmt.Errorf("Unable to parse the ports to be published, should be in format <host>:<guest> or <host>:<guest>/<tcp|udp>")
-	}
-
-	hostPort, err := strconv.Atoi(slice[0])
-
-	if err != nil {
-		return p, fmt.Errorf("The provided hostPort can't be converted to int")
-	}
-
-	right := strings.Split(slice[1], "/")
-
-	protocol := "tcp"
-	if len(right) == 2 {
-		protocol = strings.TrimSpace(strings.ToLower(right[1]))
-	}
-
-	if protocol != "tcp" && protocol != "udp" {
-		return p, fmt.Errorf("Provided protocol is not valid, valid options are: udp and tcp")
-	}
-	guestPort, err := strconv.Atoi(right[0])
-
-	if err != nil {
-		return p, fmt.Errorf("The provided guestPort can't be converted to int")
-	}
-
-	if hostPort < 1 || hostPort > 65535 {
-		return p, fmt.Errorf("Invalid hostPort: %d", hostPort)
-	}
-
-	if guestPort < 1 || guestPort > 65535 {
-		return p, fmt.Errorf("Invalid guestPort: %d", guestPort)
-	}
-
-	p.guest = guestPort
-	p.host = hostPort
-	p.protocol = protocol
-	return p, nil
-}
-
 func buildQemuForwardings(publishFlags multipleFlag, containerized bool) (string, error) {
 	if len(publishFlags) == 0 {
 		return "", nil
 	}
 	var forwardings string
 	for _, publish := range publishFlags {
-		p, err := splitPublish(publish)
+		p, err := NewPublishedPort(publish)
 		if err != nil {
 			return "", err
 		}
@@ -705,7 +655,7 @@ func buildQemuForwardings(publishFlags multipleFlag, containerized bool) (string
 func buildDockerForwardings(publishedPorts []string) ([]string, error) {
 	pmap := []string{}
 	for _, port := range publishedPorts {
-		s, err := splitPublish(port)
+		s, err := NewPublishedPort(port)
 		if err != nil {
 			return nil, err
 		}
diff --git a/src/cmd/linuxkit/util.go b/src/cmd/linuxkit/util.go
index 39d794cb1..1f02fa622 100644
--- a/src/cmd/linuxkit/util.go
+++ b/src/cmd/linuxkit/util.go
@@ -191,3 +191,55 @@ func (l *Disks) Set(value string) error {
 	*l = append(*l, d)
 	return nil
 }
+
+// PublishedPort is used by some backends to expose a VMs port on the host
+type PublishedPort struct {
+	guest    int
+	host     int
+	protocol string
+}
+
+// NewPublishedPort parses a string of the form <host>:<guest>[/<tcp|udp>] and returns a PublishedPort structure
+func NewPublishedPort(publish string) (PublishedPort, error) {
+	p := PublishedPort{}
+	slice := strings.Split(publish, ":")
+
+	if len(slice) < 2 {
+		return p, fmt.Errorf("Unable to parse the ports to be published, should be in format <host>:<guest> or <host>:<guest>/<tcp|udp>")
+	}
+
+	hostPort, err := strconv.Atoi(slice[0])
+
+	if err != nil {
+		return p, fmt.Errorf("The provided hostPort can't be converted to int")
+	}
+
+	right := strings.Split(slice[1], "/")
+
+	protocol := "tcp"
+	if len(right) == 2 {
+		protocol = strings.TrimSpace(strings.ToLower(right[1]))
+	}
+
+	if protocol != "tcp" && protocol != "udp" {
+		return p, fmt.Errorf("Provided protocol is not valid, valid options are: udp and tcp")
+	}
+	guestPort, err := strconv.Atoi(right[0])
+
+	if err != nil {
+		return p, fmt.Errorf("The provided guestPort can't be converted to int")
+	}
+
+	if hostPort < 1 || hostPort > 65535 {
+		return p, fmt.Errorf("Invalid hostPort: %d", hostPort)
+	}
+
+	if guestPort < 1 || guestPort > 65535 {
+		return p, fmt.Errorf("Invalid guestPort: %d", guestPort)
+	}
+
+	p.guest = guestPort
+	p.host = hostPort
+	p.protocol = protocol
+	return p, nil
+}