Add support for CGroups

.github/workflows/build.yaml

@@ -16,7 +16,7 @@ on:
 
 jobs:
   build:
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-24.04
     steps:
     - name: Checkout code
       uses: actions/checkout@v4
@@ -46,6 +46,10 @@ jobs:
     - name: Set up gotestfmt
       run: go install github.com/gotesttools/gotestfmt/v2/cmd/gotestfmt@latest
 
+    - name: Check systemd version
+      run: |
+        sudo systemctl --version
+
     - name: Test
       run: |
         sudo --preserve-env \

.github/workflows/lint.yaml

@@ -22,7 +22,7 @@ permissions:
 jobs:
   golangci:
     name: lint
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-24.04
     steps:
     - name: Checkout code
       uses: actions/checkout@v4

.github/workflows/website.yaml

@@ -19,7 +19,7 @@ defaults:
 jobs:
   deploy:
     name: Build and deploy website
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-24.04
     environment: release
     steps:
     - name: Checkout

LICENSES/BSD-3-Clause.txt

@@ -0,0 +1,11 @@
+Copyright (c) <year> <owner>. 
+
+Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:
+
+1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
+
+2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.
+
+3. Neither the name of the copyright holder nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

Makefile

@@ -3,14 +3,15 @@
 
 GIT_TAG = $(shell git describe --tags HEAD)
 
-GOFLAGS = -ldflags "-X main.tag=$(GIT_TAG)"
+export GOFLAGS = -buildvcs=false -ldflags=-X=main.tag=$(GIT_TAG)
 
 all: gontc
 
 tests:
-	sudo -E go test ./pkg ./internal -v $(TEST_OPTS)
+	sudo -E go test ./pkg -v $(TEST_OPTS)
+	sudo -E go test ./internal -v $(TEST_OPTS)
 
 gontc:
-	go build $(GOFLAGS) -o $@ ./cmd/gontc
+	go build -o $@ ./cmd/gontc
 
 .PHONY: all gontc

README.md

@@ -26,7 +26,7 @@ Integration tests can be automated and executed in CI environments like GitHub a
 
 ## Getting started
 
-Have a look at our **[slide set](https://cunicu.github.io/gont/)** to get you started.
+Have a look at our **[slide set](https://gont.cunicu.li/slides/)** to get you started.
 
 ## Features
 

cmd/gontc/clean.go

@@ -0,0 +1,38 @@
+// SPDX-FileCopyrightText: 2023 Steffen Vogel <[email protected]>
+// SPDX-License-Identifier: Apache-2.0
+
+package main
+
+import (
+	"context"
+	"fmt"
+	"time"
+
+	g "cunicu.li/gont/v2/pkg"
+	"github.com/coreos/go-systemd/v22/dbus"
+)
+
+func clean(args []string) error {
+	ctx := context.Background()
+	ctx, _ = context.WithTimeout(ctx, 30*time.Second) //nolint:govet
+
+	c, err := dbus.NewWithContext(ctx)
+	if err != nil {
+		return fmt.Errorf("failed to connect to D-Bus: %w", err)
+	}
+
+	networks := args[1:]
+	if len(networks) == 0 {
+		networks = g.NetworkNames()
+	}
+
+	for _, name := range networks {
+		if err := g.TeardownNetwork(ctx, c, name); err != nil {
+			return fmt.Errorf("failed to teardown network '%s': %w", name, err)
+		}
+
+		fmt.Println(name)
+	}
+
+	return nil
+}

cmd/gontc/exec.go

@@ -0,0 +1,56 @@
+// SPDX-FileCopyrightText: 2023 Steffen Vogel <[email protected]>
+// SPDX-License-Identifier: Apache-2.0
+
+package main
+
+import (
+	"flag"
+	"fmt"
+	"os"
+
+	g "cunicu.li/gont/v2/pkg"
+	sdbus "github.com/coreos/go-systemd/v22/dbus"
+	"github.com/godbus/dbus/v5"
+)
+
+func exec(network, node string, args []string) error {
+	if len(flag.Args()) <= 1 {
+		return fmt.Errorf("not enough arguments")
+	}
+
+	if network == "" {
+		return fmt.Errorf("there is no active Gont network")
+	}
+
+	if err := os.Setenv("GONT_NETWORK", network); err != nil {
+		return err
+	}
+	if err := os.Setenv("GONT_NODE", node); err != nil {
+		return err
+	}
+
+	sliceName := fmt.Sprintf("gont-%s-%s", network, node)
+	scopeName := fmt.Sprintf("gont-run-%d", os.Getpid())
+
+	cgroup, err := g.NewCGroup(nil, "scope", scopeName)
+	if err != nil {
+		return fmt.Errorf("failed to create cgroup: %w", err)
+	}
+
+	cgroup.Properties = append(cgroup.Properties,
+		sdbus.Property{
+			Name:  "Slice",
+			Value: dbus.MakeVariant(sliceName + ".slice"),
+		},
+		sdbus.Property{
+			Name:  "PIDs",
+			Value: dbus.MakeVariant([]uint{uint(os.Getpid())}), //nolint:gosec
+		},
+	)
+
+	if err := cgroup.Start(); err != nil {
+		return fmt.Errorf("failed to start cgroup: %w", err)
+	}
+
+	return g.Exec(network, node, args)
+}

cmd/gontc/gc.go

@@ -0,0 +1,34 @@
+// SPDX-FileCopyrightText: 2023 Steffen Vogel <[email protected]>
+// SPDX-License-Identifier: Apache-2.0
+
+package main
+
+import (
+	"context"
+	"fmt"
+	"time"
+
+	g "cunicu.li/gont/v2/pkg"
+	"github.com/coreos/go-systemd/v22/dbus"
+)
+
+func collectGarbage(args []string) error {
+	ctx := context.Background()
+	ctx, _ = context.WithTimeout(ctx, 10*time.Second) //nolint:govet
+
+	c, err := dbus.NewWithContext(ctx)
+	if err != nil {
+		return fmt.Errorf("failed to connect to D-Bus: %w", err)
+	}
+
+	deleted, err := g.TeardownStaleCgroups(ctx, c)
+	if err != nil {
+		return err
+	}
+
+	for _, name := range deleted {
+		fmt.Println(name)
+	}
+
+	return nil
+}

cmd/gontc/gontc.go

@@ -13,7 +13,6 @@ import (
 	"strings"
 
 	"cunicu.li/gont/v2/internal"
-	"cunicu.li/gont/v2/internal/utils"
 	g "cunicu.li/gont/v2/pkg"
 	"golang.org/x/exp/slices"
 )
@@ -97,6 +96,9 @@ func main() {
 	case "version":
 		version()
 
+	case "gc":
+		err = collectGarbage(args)
+
 	case "help":
 		flag.Usage()
 		err = nil
@@ -141,80 +143,3 @@ func networkNode(args []string) (string, string, error) {
 
 	return network, node, nil
 }
-
-func version() {
-	version := "unknown"
-	if tag != "" {
-		version = tag
-	}
-
-	if ok, rev, dirty, btime := utils.ReadVCSInfos(); ok {
-		dirtyFlag := ""
-		if dirty {
-			dirtyFlag = "-dirty"
-		}
-
-		fmt.Printf("%s (%s%s, build on %s)\n", version, rev[:8], dirtyFlag, btime.String())
-	} else {
-		fmt.Println(version)
-	}
-}
-
-func list(args []string) {
-	if len(args) > 1 {
-		network := args[1]
-		for _, name := range g.NodeNames(network) {
-			fmt.Printf("%s/%s\n", network, name)
-		}
-	} else {
-		for _, name := range g.NetworkNames() {
-			fmt.Println(name)
-		}
-	}
-}
-
-func clean(args []string) error {
-	if len(args) > 1 {
-		network := args[1]
-		if err := g.TeardownNetwork(network); err != nil {
-			return fmt.Errorf("failed to teardown network '%s': %w", network, err)
-		}
-	} else {
-		return g.TeardownAllNetworks()
-	}
-
-	return nil
-}
-
-func exec(network, node string, args []string) error {
-	if len(flag.Args()) <= 1 {
-		return fmt.Errorf("not enough arguments")
-	}
-
-	if network == "" {
-		return fmt.Errorf("there is no active Gont network")
-	}
-
-	if err := os.Setenv("GONT_NETWORK", network); err != nil {
-		return err
-	}
-	if err := os.Setenv("GONT_NODE", node); err != nil {
-		return err
-	}
-
-	return g.Exec(network, node, args)
-}
-
-func shell(network, node string) error {
-	shell := os.Getenv("SHELL")
-	if shell == "" {
-		shell = "/bin/bash"
-	}
-
-	ps1 := fmt.Sprintf("%s/%s: ", network, node)
-	os.Setenv("PS1", ps1)
-
-	cmd := []string{shell, "--norc"}
-
-	return exec(network, node, cmd)
-}

cmd/gontc/list.go

@@ -0,0 +1,23 @@
+// SPDX-FileCopyrightText: 2023 Steffen Vogel <[email protected]>
+// SPDX-License-Identifier: Apache-2.0
+
+package main
+
+import (
+	"fmt"
+
+	g "cunicu.li/gont/v2/pkg"
+)
+
+func list(args []string) {
+	if len(args) > 1 {
+		network := args[1]
+		for _, name := range g.NodeNames(network) {
+			fmt.Printf("%s/%s\n", network, name)
+		}
+	} else {
+		for _, name := range g.NetworkNames() {
+			fmt.Println(name)
+		}
+	}
+}

cmd/gontc/shell.go

@@ -0,0 +1,23 @@
+// SPDX-FileCopyrightText: 2023 Steffen Vogel <[email protected]>
+// SPDX-License-Identifier: Apache-2.0
+
+package main
+
+import (
+	"fmt"
+	"os"
+)
+
+func shell(network, node string) error {
+	shell := os.Getenv("SHELL")
+	if shell == "" {
+		shell = "/bin/bash"
+	}
+
+	ps1 := fmt.Sprintf("%s/%s: ", network, node)
+	os.Setenv("PS1", ps1)
+
+	cmd := []string{shell, "--norc"}
+
+	return exec(network, node, cmd)
+}

cmd/gontc/version.go

@@ -0,0 +1,28 @@
+// SPDX-FileCopyrightText: 2023 Steffen Vogel <[email protected]>
+// SPDX-License-Identifier: Apache-2.0
+
+package main
+
+import (
+	"fmt"
+
+	"cunicu.li/gont/v2/internal/utils"
+)
+
+func version() {
+	version := "unknown"
+	if tag != "" {
+		version = tag
+	}
+
+	if ok, rev, dirty, btime := utils.ReadVCSInfos(); ok {
+		dirtyFlag := ""
+		if dirty {
+			dirtyFlag = "-dirty"
+		}
+
+		fmt.Printf("%s (%s%s, build on %s)\n", version, rev[:8], dirtyFlag, btime.String())
+	} else {
+		fmt.Println(version)
+	}
+}

default.nix

@@ -4,7 +4,7 @@
 buildGoModule {
   name = "gont";
   src = ./.;
-  vendorHash = "sha256-IXTpMzTrWRH10vB6hRsMf7ilT5tUG/EPJbYLO+8d9Ik=";
+  vendorHash = "sha256-EAwP8nNyS6lnLi/OBxxdZzePIiy30l6uFr1Z8SPAllA=";
   buildInputs = [ libpcap ];
   doCheck = false;
 }