reference basis

.github/workflows/automerge.yml

+# File managed by web3-bot. DO NOT EDIT.
+# See https://github.com/protocol/.github/ for details.
+
+# Automatically merge pull requests opened by web3-bot, as soon as (and only if) all tests pass.
+# This reduces the friction associated with updating with our workflows.
+
+on: [ pull_request ]
+name: Automerge
+
+jobs:
+  automerge-check:
+    if: github.event.pull_request.user.login == 'web3-bot'
+    runs-on: ubuntu-latest
+    outputs:
+      status: ${{ steps.should-automerge.outputs.status }}
+    steps:
+    - uses: actions/checkout@v2
+      with:
+        fetch-depth: 0
+    - name: Check if we should automerge
+      id: should-automerge
+      run: |
+        for commit in $(git rev-list --first-parent origin/${{ github.event.pull_request.base.ref }}..${{ github.event.pull_request.head.sha }}); do
+          committer=$(git show --format=$'%ce' -s $commit)
+          echo "Committer: $committer"
+          if [[ "$committer" != "web3-bot@users.noreply.github.com" ]]; then
+            echo "Commit $commit wasn't committed by web3-bot, but by $committer."
+            echo "::set-output name=status::false"
+            exit
+          fi
+        done
+        echo "::set-output name=status::true"
+  automerge:
+    needs: automerge-check
+    runs-on: ubuntu-latest
+    if: ${{ needs.automerge-check.outputs.status == 'true' }}
+    steps:
+    - name: Wait on tests
+      uses: lewagon/wait-on-check-action@bafe56a6863672c681c3cf671f5e10b20abf2eaa # v0.2
+      with:
+        ref: ${{ github.event.pull_request.head.sha }}
+        repo-token: ${{ secrets.GITHUB_TOKEN }}
+        wait-interval: 10
+        running-workflow-name: 'automerge' # the name of this job
+    - name: Merge PR
+      uses: pascalgn/automerge-action@741c311a47881be9625932b0a0de1b0937aab1ae # v0.13.1
+      env:
+        GITHUB_TOKEN: "${{ secrets.GITHUB_TOKEN }}"
+        MERGE_LABELS: ""
+        MERGE_METHOD: "squash"
+        MERGE_DELETE_BRANCH: true

.github/workflows/go-check.yml

+# File managed by web3-bot. DO NOT EDIT.
+# See https://github.com/protocol/.github/ for details.
+
+on: [push, pull_request]
+name: Go Checks
+
+jobs:
+  unit:
+    runs-on: ubuntu-latest
+    name: All
+    steps:
+      - uses: actions/checkout@v2
+        with:
+          submodules: recursive
+      - uses: actions/setup-go@v2
+        with:
+          go-version: "1.16.x"
+      - name: Install staticcheck
+        run: go install honnef.co/go/tools/cmd/staticcheck@434f5f3816b358fe468fa83dcba62d794e7fe04b # 2021.1 (v0.2.0)
+      - name: Check that go.mod is tidy
+        uses: protocol/multiple-go-modules@v1.0
+        with:
+          run: |
+            go mod tidy
+            if [[ -n $(git ls-files --other --exclude-standard --directory -- go.sum) ]]; then
+              echo "go.sum was added by go mod tidy"
+              exit 1
+            fi
+            git diff --exit-code -- go.sum go.mod
+      - name: gofmt
+        if: ${{ success() || failure() }} # run this step even if the previous one failed
+        run: |
+          out=$(gofmt -s -l .)
+          if [[ -n "$out" ]]; then
+            echo $out | awk '{print "::error file=" $0 ",line=0,col=0::File is not gofmt-ed."}'
+            exit 1
+          fi
+      - name: go vet
+        if: ${{ success() || failure() }} # run this step even if the previous one failed
+        uses: protocol/multiple-go-modules@v1.0
+        with:
+          run: go vet ./...
+      - name: staticcheck
+        if: ${{ success() || failure() }} # run this step even if the previous one failed
+        uses: protocol/multiple-go-modules@v1.0
+        with:
+          run: |
+            set -o pipefail
+            staticcheck ./... | sed -e 's@\(.*\)\.go@./\1.go@g'
+

.github/workflows/go-test.yml

+# File managed by web3-bot. DO NOT EDIT.
+# See https://github.com/protocol/.github/ for details.
+
+on: [push, pull_request]
+name: Go Test
+
+jobs:
+  unit:
+    strategy:
+      fail-fast: false
+      matrix:
+        os: [ "ubuntu", "windows", "macos" ]
+        go: [ "1.15.x", "1.16.x" ]
+    runs-on: ${{ matrix.os }}-latest
+    name: ${{ matrix.os}} (go ${{ matrix.go }})
+    steps:
+      - uses: actions/checkout@v2
+        with:
+          submodules: recursive
+      - uses: actions/setup-go@v2
+        with:
+          go-version: ${{ matrix.go }}
+      - name: Go information
+        run: |
+          go version
+          go env
+      - name: Run tests
+        uses: protocol/multiple-go-modules@v1.0
+        with:
+          run: go test -v -coverprofile coverage.txt ./...
+      - name: Run tests (32 bit)
+        if: ${{ matrix.os != 'macos' }} # can't run 32 bit tests on OSX.
+        uses: protocol/multiple-go-modules@v1.0
+        env:
+          GOARCH: 386
+        with:
+          run: go test -v ./...
+      - name: Run tests with race detector
+        if: ${{ matrix.os == 'ubuntu' }} # speed things up. Windows and OSX VMs are slow
+        uses: protocol/multiple-go-modules@v1.0
+        with:
+          run: go test -v -race ./...
+      - name: Upload coverage to Codecov
+        uses: codecov/codecov-action@a1ed4b322b4b38cb846afb5a0ebfa17086917d27 # v1.5.0
+        with:
+          file: coverage.txt
+          env_vars: OS=${{ matrix.os }}, GO=${{ matrix.go }}

LICENSE

+The MIT License (MIT)
+
+Copyright (c) 2019 Protocol Labs
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.

README.md

-# go-socket-activation
+go-socket-activation
+==================
 
-dms3 p2p go-socket-activation
\ No newline at end of file
+[![](https://img.shields.io/badge/made%20by-Protocol%20Labs-blue.svg?style=flat-square)](https://protocol.ai)
+[![](https://img.shields.io/badge/project-libp2p-yellow.svg?style=flat-square)](https://libp2p.io/)
+[![](https://img.shields.io/badge/freenode-%23libp2p-yellow.svg?style=flat-square)](https://webchat.freenode.net/?channels=%23libp2p)
+[![Coverage Status](https://img.shields.io/codecov/c/github/libp2p/go-socket-activation.svg?style=flat-square&branch=master)](https://codecov.io/github/libp2p/go-socket-activation?branch=master)
+[![Travis CI](https://travis-ci.org/libp2p/go-socket-activation.svg?branch=master)](https://travis-ci.org/libp2p/go-socket-activation)
+[![Discourse posts](https://img.shields.io/discourse/https/discuss.libp2p.io/posts.svg)](https://discuss.libp2p.io)
+
+
+> A library for creating socket-activated processes.
+
+This library provides access to sockets registered by the system's init daemon.
+See: http://0pointer.de/blog/projects/socket-activation.html for details.
+
+At the moment, this library only supports systemd.
+
+## Table of Contents
+
+- [Install](#install)
+- [Contribute](#contribute)
+- [License](#license)
+
+## Install
+
+```sh
+go get -u github.com/libp2p/go-socket-activation
+```
+
+## Usage
+
+
+## Contribute
+
+PRs are welcome!
+
+Small note: If editing the Readme, please conform to the [standard-readme](https://github.com/RichardLitt/standard-readme) specification.
+
+## License
+
+MIT © 2019 Protocol Labs

codecov.yml

+coverage:
+  range: "50...100"
+comment: off

go.mod

+module github.com/libp2p/go-socket-activation
+
+go 1.15
+
+require (
+	github.com/coreos/go-systemd/v22 v22.0.0
+	github.com/ipfs/go-log v1.0.3
+	github.com/multiformats/go-multiaddr-net v0.1.2
+)

go.sum

+github.com/coreos/go-systemd/v22 v22.0.0 h1:XJIw/+VlJ+87J+doOxznsAWIdmWuViOVhkQamW5YV28=
+github.com/coreos/go-systemd/v22 v22.0.0/go.mod h1:xO0FLkIi5MaZafQlIrOotqXZ90ih+1atmu1JpKERPPk=
+github.com/davecgh/go-spew v1.1.0 h1:ZDRjVQ15GmhC3fiQ8ni8+OwkZQO4DARzQgrnXU1Liz8=
+github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/godbus/dbus/v5 v5.0.3/go.mod h1:xhWf0FNVPg57R7Z0UbKHbJfkEywrmjJnf7w5xrFpKfA=
+github.com/gogo/protobuf v1.2.1 h1:/s5zKNz0uPFCZ5hddgPdo2TK2TVrUNMn0OOX8/aZMTE=
+github.com/gogo/protobuf v1.2.1/go.mod h1:hp+jE20tsWTFYpLwKvXlhS1hjn+gTNwPg2I6zVXpSg4=
+github.com/ipfs/go-log v1.0.3 h1:Gg7SUYSZ7BrqaKMwM+hRgcAkKv4QLfzP4XPQt5Sx/OI=
+github.com/ipfs/go-log v1.0.3/go.mod h1:OsLySYkwIbiSUR/yBTdv1qPtcE4FW3WPWk/ewz9Ru+A=
+github.com/ipfs/go-log/v2 v2.0.3 h1:Q2gXcBoCALyLN/pUQlz1qgu0x3uFV6FzP9oXhpfyJpc=
+github.com/ipfs/go-log/v2 v2.0.3/go.mod h1:O7P1lJt27vWHhOwQmcFEvlmo49ry2VY2+JfBWFaa9+0=
+github.com/kisielk/errcheck v1.1.0/go.mod h1:EZBBE59ingxPouuu3KfxchcWSUPOHkagtvWXihfKN4Q=
+github.com/kisielk/gotool v1.0.0/go.mod h1:XhKaO+MFFWcvkIS/tQcRk01m1F5IRFswLeQ+oQHNcck=
+github.com/minio/blake2b-simd v0.0.0-20160723061019-3f5f724cb5b1 h1:lYpkrQH5ajf0OXOcUbGjvZxxijuBwbbmlSxLiuofa+g=
+github.com/minio/blake2b-simd v0.0.0-20160723061019-3f5f724cb5b1/go.mod h1:pD8RvIylQ358TN4wwqatJ8rNavkEINozVn9DtGI3dfQ=
+github.com/minio/sha256-simd v0.1.1-0.20190913151208-6de447530771 h1:MHkK1uRtFbVqvAgvWxafZe54+5uBxLluGylDiKgdhwo=
+github.com/minio/sha256-simd v0.1.1-0.20190913151208-6de447530771/go.mod h1:B5e1o+1/KgNmWrSQK08Y6Z1Vb5pwIktudl0J58iy0KM=
+github.com/mr-tron/base58 v1.1.2 h1:ZEw4I2EgPKDJ2iEw0cNmLB3ROrEmkOtXIkaG7wZg+78=
+github.com/mr-tron/base58 v1.1.2/go.mod h1:BinMc/sQntlIE1frQmRFPUoPA1Zkr8VRgBdjWI2mNwc=
+github.com/multiformats/go-multiaddr v0.2.0 h1:lR52sFwcTCuQb6bTfnXF6zA2XfyYvyd+5a9qECv/J90=
+github.com/multiformats/go-multiaddr v0.2.0/go.mod h1:0nO36NvPpyV4QzvTLi/lafl2y95ncPj0vFwVF6k6wJ4=
+github.com/multiformats/go-multiaddr-net v0.1.2 h1:P7zcBH9FRETdPkDrylcXVjQLQ2t1JQtNItZULWNWgeg=
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+github.com/multiformats/go-multihash v0.0.8 h1:wrYcW5yxSi3dU07n5jnuS5PrNwyHy0zRHGVoUugWvXg=
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sockets.go

+package sockets
+
+import (
+	"sync"
+
+	manet "github.com/multiformats/go-multiaddr-net"
+)
+
+var (
+	mu          sync.Mutex
+	initFn      = func() {}
+	initialized = false
+	listeners   = make(map[string][]manet.Listener)
+	packetConns = make(map[string][]manet.PacketConn)
+)
+
+func initialize() {
+	if !initialized {
+		initFn()
+		initialized = true
+	}
+}
+
+// TakeSockets takes the listeners associated with the given name.
+func TakeListeners(name string) ([]manet.Listener, error) {
+	mu.Lock()
+	defer mu.Unlock()
+	initialize()
+
+	s := listeners[name]
+	delete(listeners, name)
+
+	return s, nil
+}
+
+// ListListeners lists the names of the available listeners.
+func ListListeners() ([]string, error) {
+	mu.Lock()
+	defer mu.Unlock()
+	initialize()
+
+	names := make([]string, 0, len(listeners))
+	for name := range listeners {
+		names = append(names, name)
+	}
+	return names, nil
+}
+
+// TakePacketConns takes the packet connections associated with the given name.
+func TakePacketConns(name string) ([]manet.PacketConn, error) {
+	mu.Lock()
+	defer mu.Unlock()
+	initialize()
+
+	s := packetConns[name]
+	delete(packetConns, name)
+
+	return s, nil
+}
+
+// ListListeners lists the names of the available packet connections.
+func ListPacketConns() ([]string, error) {
+	mu.Lock()
+	defer mu.Unlock()
+	initialize()
+
+	names := make([]string, 0, len(packetConns))
+	for name := range packetConns {
+		names = append(names, name)
+	}
+	return names, nil
+}

sockets_linux.go

+// +build linux
+
+package sockets
+
+import (
+	"fmt"
+	"net"
+	"os"
+	"syscall"
+
+	activation "github.com/coreos/go-systemd/v22/activation"
+	logging "github.com/ipfs/go-log"
+	manet "github.com/multiformats/go-multiaddr-net"
+)
+
+var log = logging.Logger("socket-activation")
+
+func isListening(file *os.File) (bool, error) {
+	ret, err := syscall.GetsockoptInt(int(file.Fd()), syscall.SOL_SOCKET, syscall.SO_ACCEPTCONN)
+	return ret == 1, err
+}
+
+func registerFile(file *os.File) error {
+	listening, err := isListening(file)
+	if err != nil {
+		return fmt.Errorf("failed determine the socket type: %s", err)
+	}
+
+	if listening {
+		listener, err := net.FileListener(file)
+		if err != nil {
+			return fmt.Errorf("failed to convert listener: %s", err)
+		}
+		mal, err := manet.WrapNetListener(listener)
+		if err != nil {
+			return fmt.Errorf("failed to wrap net listener: %s", err)
+		}
+		listeners[file.Name()] = append(listeners[file.Name()], mal)
+	} else {
+		pc, err := net.FilePacketConn(file)
+		if err != nil {
+			return fmt.Errorf("failed to convert to a packet conn: %s", err)
+		}
+		mapc, err := manet.WrapPacketConn(pc)
+		if err != nil {
+			return fmt.Errorf("failed to wrap net packet conn: %s", err)
+		}
+		packetConns[file.Name()] = append(packetConns[file.Name()], mapc)
+	}
+	return nil
+}
+
+func init() {
+	// Initialize lazily as this isn't _free_.
+	initFn = func() {
+		for _, file := range activation.Files(true) {
+			err := registerFile(file)
+			file.Close()
+			if err != nil {
+				log.Errorf("when handling the socket %s: %s", file.Name(), err)
+			}
+		}
+	}
+
+}

sockets_test.go

+// +build linux
+
+package sockets
+
+import (
+	"fmt"
+	"io/ioutil"
+	"net"
+	"os"
+	"os/exec"
+	"strconv"
+	"testing"
+)
+
+func TestActivation(t *testing.T) {
+	testTcpAddr := os.Getenv("SOCKET_TEST_TCP_ADDR")
+	testUdpAddr := os.Getenv("SOCKET_TEST_UDP_ADDR")
+	if testTcpAddr == "" {
+		lt, err := net.ListenTCP("tcp", &net.TCPAddr{IP: net.IPv6loopback})
+		if err != nil {
+			t.Fatal(err)
+		}
+		tcpAddr := lt.Addr()
+		ltf, err := lt.File()
+		lt.Close()
+		if err != nil {
+			t.Fatal(err)
+		}
+
+		lu, err := net.ListenUDP("udp", &net.UDPAddr{IP: net.IPv6loopback})
+		if err != nil {
+			t.Fatal(err)
+		}
+		udpAddr := lu.LocalAddr()
+		luf, err := lu.File()
+		lu.Close()
+		if err != nil {
+			t.Fatal(err)
+		}
+
+		cmd := exec.Command("/proc/self/exe", "-test.run", "TestActivation")
+		cmd.ExtraFiles = append(cmd.ExtraFiles, ltf, luf)
+		cmd.Stdout = os.Stdout
+		cmd.Stderr = os.Stderr
+		cmd.Env = append(
+			cmd.Env,
+			"LISTEN_FDS=2",
+			"LISTEN_FDNAMES=tcp:udp",
+			fmt.Sprintf("SOCKET_TEST_TCP_ADDR=%s", tcpAddr),
+			fmt.Sprintf("SOCKET_TEST_UDP_ADDR=%s", udpAddr),
+		)
+		err = cmd.Run()
+		if err != nil {
+			t.Fatal(err)
+		}
+	} else {
+		// can't set this from the parent because we can't run anything between fork/exec.
+		os.Setenv("LISTEN_PID", strconv.Itoa(os.Getpid()))
+		tcp, err := TakeListeners("tcp")
+		if err != nil {
+			t.Fatal(err)
+		}
+		if len(tcp) != 1 {
+			t.Fatalf("expected 1 listener, got %d", len(tcp))
+		}
+
+		go func() {
+			l := tcp[0]
+			c, err := l.Accept()
+			if err != nil {
+				t.Error(err)
+				return
+			}
+			c.Write([]byte("foobar"))
+			c.Close()
+		}()
+		c, err := net.Dial("tcp6", testTcpAddr)
+		if err != nil {
+			t.Fatal(err)
+		}
+		b, err := ioutil.ReadAll(c)
+		if err != nil {
+			t.Error(err)
+		}
+		if string(b) != "foobar" {
+			t.Error("wrong message")
+		}
+		udp, err := TakePacketConns("udp")
+		if err != nil {
+			t.Fatal(err)
+		}
+		if len(udp) != 1 {
+			t.Fatalf("expected 1 listener, got %d", len(tcp))
+		}
+		if udp[0].LocalAddr().String() != testUdpAddr {
+			t.Fatal("got the wrong udp listener")
+		}
+	}
+}