1
0
Fork 0
mirror of https://github.com/restic/restic.git synced 2024-12-25 17:27:25 +00:00
restic/build.go
Alexander Neumann 6e1a3987b7 Add 'self-update' command
This commit adds a command called `self-update` which downloads the
latest released version of restic from GitHub and replacing the current
binary with it. It does not rely on any external program (so it'll work
everywhere), but still verifies the GPG signature using the embedded GPG
public key.

By default, the `self-update` command is hidden behind the `selfupdate`
built tag, which is only set when restic is built using `build.go`. The
reason for this is that downstream distributions will then not include
the command by default, so users are encouraged to use the
platform-specific distribution mechanism.
2018-08-12 23:34:47 +02:00

618 lines
15 KiB
Go

// BSD 2-Clause License
//
// Copyright (c) 2016-2018, Alexander Neumann <alexander@bumpern.de>
// All rights reserved.
//
// This file has been copied from the repository at:
// https://github.com/fd0/build-go
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are met:
//
// * Redistributions of source code must retain the above copyright notice, this
// list of conditions and the following disclaimer.
//
// * 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.
//
// 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.
// +build ignore_build_go
package main
import (
"fmt"
"io"
"io/ioutil"
"os"
"os/exec"
"path"
"path/filepath"
"runtime"
"strconv"
"strings"
)
// config contains the configuration for the program to build.
var config = Config{
Name: "restic", // name of the program executable and directory
Namespace: "github.com/restic/restic", // subdir of GOPATH, e.g. "github.com/foo/bar"
Main: "github.com/restic/restic/cmd/restic", // package name for the main package
DefaultBuildTags: []string{"selfupdate"}, // specify build tags which are always used
Tests: []string{ // tests to run
"github.com/restic/restic/internal/...",
"github.com/restic/restic/cmd/...",
},
MinVersion: GoVersion{Major: 1, Minor: 9, Patch: 0}, // minimum Go version supported
}
// Config configures the build.
type Config struct {
Name string
Namespace string
Main string
DefaultBuildTags []string
Tests []string
MinVersion GoVersion
}
var (
verbose bool
keepGopath bool
runTests bool
enableCGO bool
enablePIE bool
)
// specialDir returns true if the file begins with a special character ('.' or '_').
func specialDir(name string) bool {
if name == "." {
return false
}
base := filepath.Base(name)
if base == "vendor" || base[0] == '_' || base[0] == '.' {
return true
}
return false
}
// excludePath returns true if the file should not be copied to the new GOPATH.
func excludePath(name string) bool {
ext := path.Ext(name)
if ext == ".go" || ext == ".s" || ext == ".h" {
return false
}
parentDir := filepath.Base(filepath.Dir(name))
if parentDir == "testdata" {
return false
}
return true
}
// updateGopath builds a valid GOPATH at dst, with all Go files in src/ copied
// to dst/prefix/, so calling
//
// updateGopath("/tmp/gopath", "/home/u/restic", "github.com/restic/restic")
//
// with "/home/u/restic" containing the file "foo.go" yields the following tree
// at "/tmp/gopath":
//
// /tmp/gopath
// └── src
// └── github.com
// └── restic
// └── restic
// └── foo.go
func updateGopath(dst, src, prefix string) error {
verbosePrintf("copy contents of %v to %v\n", src, filepath.Join(dst, prefix))
return filepath.Walk(src, func(name string, fi os.FileInfo, err error) error {
if name == src {
return err
}
if specialDir(name) {
if fi.IsDir() {
return filepath.SkipDir
}
return nil
}
if err != nil {
return err
}
if fi.IsDir() {
return nil
}
if excludePath(name) {
return nil
}
intermediatePath, err := filepath.Rel(src, name)
if err != nil {
return err
}
fileSrc := filepath.Join(src, intermediatePath)
fileDst := filepath.Join(dst, "src", prefix, intermediatePath)
return copyFile(fileDst, fileSrc)
})
}
func directoryExists(dirname string) bool {
stat, err := os.Stat(dirname)
if err != nil && os.IsNotExist(err) {
return false
}
return stat.IsDir()
}
// copyFile creates dst from src, preserving file attributes and timestamps.
func copyFile(dst, src string) error {
fi, err := os.Stat(src)
if err != nil {
return err
}
fsrc, err := os.Open(src)
if err != nil {
return err
}
if err = os.MkdirAll(filepath.Dir(dst), 0755); err != nil {
fmt.Printf("MkdirAll(%v)\n", filepath.Dir(dst))
return err
}
fdst, err := os.Create(dst)
if err != nil {
return err
}
if _, err = io.Copy(fdst, fsrc); err != nil {
return err
}
if err == nil {
err = fsrc.Close()
}
if err == nil {
err = fdst.Close()
}
if err == nil {
err = os.Chmod(dst, fi.Mode())
}
if err == nil {
err = os.Chtimes(dst, fi.ModTime(), fi.ModTime())
}
return nil
}
// die prints the message with fmt.Fprintf() to stderr and exits with an error
// code.
func die(message string, args ...interface{}) {
fmt.Fprintf(os.Stderr, message, args...)
os.Exit(1)
}
func showUsage(output io.Writer) {
fmt.Fprintf(output, "USAGE: go run build.go OPTIONS\n")
fmt.Fprintf(output, "\n")
fmt.Fprintf(output, "OPTIONS:\n")
fmt.Fprintf(output, " -v --verbose output more messages\n")
fmt.Fprintf(output, " -t --tags specify additional build tags\n")
fmt.Fprintf(output, " -k --keep-gopath do not remove the GOPATH after build\n")
fmt.Fprintf(output, " -T --test run tests\n")
fmt.Fprintf(output, " -o --output set output file name\n")
fmt.Fprintf(output, " --enable-cgo use CGO to link against libc\n")
fmt.Fprintf(output, " --enable-pie use PIE buildmode\n")
fmt.Fprintf(output, " --goos value set GOOS for cross-compilation\n")
fmt.Fprintf(output, " --goarch value set GOARCH for cross-compilation\n")
fmt.Fprintf(output, " --goarm value set GOARM for cross-compilation\n")
fmt.Fprintf(output, " --tempdir dir use a specific directory for compilation\n")
}
func verbosePrintf(message string, args ...interface{}) {
if !verbose {
return
}
fmt.Printf("build: "+message, args...)
}
// cleanEnv returns a clean environment with GOPATH, GOBIN and GO111MODULE
// removed (if present).
func cleanEnv() (env []string) {
removeKeys := map[string]struct{}{
"GOPATH": struct{}{},
"GOBIN": struct{}{},
"GO111MODULE": struct{}{},
}
for _, v := range os.Environ() {
data := strings.SplitN(v, "=", 2)
name := data[0]
if _, ok := removeKeys[name]; ok {
continue
}
env = append(env, v)
}
return env
}
// build runs "go build args..." with GOPATH set to gopath.
func build(cwd string, ver GoVersion, goos, goarch, goarm, gopath string, args ...string) error {
a := []string{"build"}
if ver.AtLeast(GoVersion{1, 10, 0}) {
verbosePrintf("Go version is at least 1.10, using new syntax for -gcflags\n")
// use new prefix
a = append(a, "-asmflags", fmt.Sprintf("all=-trimpath=%s", gopath))
a = append(a, "-gcflags", fmt.Sprintf("all=-trimpath=%s", gopath))
} else {
a = append(a, "-asmflags", fmt.Sprintf("-trimpath=%s", gopath))
a = append(a, "-gcflags", fmt.Sprintf("-trimpath=%s", gopath))
}
if enablePIE {
a = append(a, "-buildmode=pie")
}
a = append(a, args...)
cmd := exec.Command("go", a...)
cmd.Env = append(cleanEnv(), "GOPATH="+gopath, "GOARCH="+goarch, "GOOS="+goos)
if goarm != "" {
cmd.Env = append(cmd.Env, "GOARM="+goarm)
}
if !enableCGO {
cmd.Env = append(cmd.Env, "CGO_ENABLED=0")
}
cmd.Dir = cwd
cmd.Stdout = os.Stdout
cmd.Stderr = os.Stderr
verbosePrintf("go %s\n", a)
return cmd.Run()
}
// test runs "go test args..." with GOPATH set to gopath.
func test(cwd, gopath string, args ...string) error {
args = append([]string{"test"}, args...)
cmd := exec.Command("go", args...)
cmd.Env = append(cleanEnv(), "GOPATH="+gopath)
cmd.Dir = cwd
cmd.Stdout = os.Stdout
cmd.Stderr = os.Stderr
verbosePrintf("go %s\n", args)
return cmd.Run()
}
// getVersion returns the version string from the file VERSION in the current
// directory.
func getVersionFromFile() string {
buf, err := ioutil.ReadFile("VERSION")
if err != nil {
verbosePrintf("error reading file VERSION: %v\n", err)
return ""
}
return strings.TrimSpace(string(buf))
}
// getVersion returns a version string which is a combination of the contents
// of the file VERSION in the current directory and the version from git (if
// available).
func getVersion() string {
versionFile := getVersionFromFile()
versionGit := getVersionFromGit()
verbosePrintf("version from file 'VERSION' is %q, version from git %q\n",
versionFile, versionGit)
switch {
case versionFile == "":
return versionGit
case versionGit == "":
return versionFile
}
return fmt.Sprintf("%s (%s)", versionFile, versionGit)
}
// getVersionFromGit returns a version string that identifies the currently
// checked out git commit.
func getVersionFromGit() string {
cmd := exec.Command("git", "describe",
"--long", "--tags", "--dirty", "--always")
out, err := cmd.Output()
if err != nil {
verbosePrintf("git describe returned error: %v\n", err)
return ""
}
version := strings.TrimSpace(string(out))
verbosePrintf("git version is %s\n", version)
return version
}
// Constants represents a set of constants that are set in the final binary to
// the given value via compiler flags.
type Constants map[string]string
// LDFlags returns the string that can be passed to go build's `-ldflags`.
func (cs Constants) LDFlags() string {
l := make([]string, 0, len(cs))
for k, v := range cs {
l = append(l, fmt.Sprintf(`-X "%s=%s"`, k, v))
}
return strings.Join(l, " ")
}
// GoVersion is the version of Go used to compile the project.
type GoVersion struct {
Major int
Minor int
Patch int
}
// ParseGoVersion parses the Go version s. If s cannot be parsed, the returned GoVersion is null.
func ParseGoVersion(s string) (v GoVersion) {
if !strings.HasPrefix(s, "go") {
return
}
s = s[2:]
data := strings.Split(s, ".")
if len(data) < 2 || len(data) > 3 {
// invalid version
return GoVersion{}
}
var err error
v.Major, err = strconv.Atoi(data[0])
if err != nil {
return GoVersion{}
}
// try to parse the minor version while removing an eventual suffix (like
// "rc2" or so)
for s := data[1]; s != ""; s = s[:len(s)-1] {
v.Minor, err = strconv.Atoi(s)
if err == nil {
break
}
}
if v.Minor == 0 {
// no minor version found
return GoVersion{}
}
if len(data) >= 3 {
v.Patch, err = strconv.Atoi(data[2])
if err != nil {
return GoVersion{}
}
}
return
}
// AtLeast returns true if v is at least as new as other. If v is empty, true is returned.
func (v GoVersion) AtLeast(other GoVersion) bool {
var empty GoVersion
// the empty version satisfies all versions
if v == empty {
return true
}
if v.Major < other.Major {
return false
}
if v.Minor < other.Minor {
return false
}
if v.Patch < other.Patch {
return false
}
return true
}
func (v GoVersion) String() string {
return fmt.Sprintf("Go %d.%d.%d", v.Major, v.Minor, v.Patch)
}
func main() {
ver := ParseGoVersion(runtime.Version())
if !ver.AtLeast(config.MinVersion) {
fmt.Fprintf(os.Stderr, "%s detected, this program requires at least %s\n", ver, config.MinVersion)
os.Exit(1)
}
buildTags := config.DefaultBuildTags
skipNext := false
params := os.Args[1:]
targetGOOS := runtime.GOOS
targetGOARCH := runtime.GOARCH
targetGOARM := ""
gopath := ""
var outputFilename string
for i, arg := range params {
if skipNext {
skipNext = false
continue
}
switch arg {
case "-v", "--verbose":
verbose = true
case "-k", "--keep-gopath":
keepGopath = true
case "-t", "-tags", "--tags":
if i+1 >= len(params) {
die("-t given but no tag specified")
}
skipNext = true
buildTags = append(buildTags, strings.Split(params[i+1], " ")...)
case "-o", "--output":
skipNext = true
outputFilename = params[i+1]
case "--tempdir":
skipNext = true
gopath = params[i+1]
case "-T", "--test":
runTests = true
case "--enable-cgo":
enableCGO = true
case "--enable-pie":
enablePIE = true
case "--goos":
skipNext = true
targetGOOS = params[i+1]
case "--goarch":
skipNext = true
targetGOARCH = params[i+1]
case "--goarm":
skipNext = true
targetGOARM = params[i+1]
case "-h":
showUsage(os.Stdout)
return
default:
fmt.Fprintf(os.Stderr, "Error: unknown option %q\n\n", arg)
showUsage(os.Stderr)
os.Exit(1)
}
}
verbosePrintf("detected Go version %v\n", ver)
if len(buildTags) == 0 {
verbosePrintf("adding build-tag release\n")
buildTags = []string{"release"}
}
for i := range buildTags {
buildTags[i] = strings.TrimSpace(buildTags[i])
}
verbosePrintf("build tags: %s\n", buildTags)
root, err := os.Getwd()
if err != nil {
die("Getwd(): %v\n", err)
}
if gopath == "" {
gopath, err = ioutil.TempDir("", fmt.Sprintf("%v-build-", config.Name))
if err != nil {
die("TempDir(): %v\n", err)
}
}
verbosePrintf("create GOPATH at %v\n", gopath)
if err = updateGopath(gopath, root, config.Namespace); err != nil {
die("copying files from %v/src to %v/src failed: %v\n", root, gopath, err)
}
vendor := filepath.Join(root, "vendor")
if directoryExists(vendor) {
if err = updateGopath(gopath, vendor, filepath.Join(config.Namespace, "vendor")); err != nil {
die("copying files from %v to %v failed: %v\n", root, gopath, err)
}
}
defer func() {
if !keepGopath {
verbosePrintf("remove %v\n", gopath)
if err = os.RemoveAll(gopath); err != nil {
die("remove GOPATH at %s failed: %v\n", gopath, err)
}
} else {
verbosePrintf("leaving temporary GOPATH at %v\n", gopath)
}
}()
if outputFilename == "" {
outputFilename = config.Name
if targetGOOS == "windows" {
outputFilename += ".exe"
}
}
cwd, err := os.Getwd()
if err != nil {
die("Getwd() returned %v\n", err)
}
output := outputFilename
if !filepath.IsAbs(output) {
output = filepath.Join(cwd, output)
}
version := getVersion()
constants := Constants{}
if version != "" {
constants["main.version"] = version
}
ldflags := "-s -w " + constants.LDFlags()
verbosePrintf("ldflags: %s\n", ldflags)
args := []string{
"-tags", strings.Join(buildTags, " "),
"-ldflags", ldflags,
"-o", output, config.Main,
}
err = build(filepath.Join(gopath, "src"), ver, targetGOOS, targetGOARCH, targetGOARM, gopath, args...)
if err != nil {
die("build failed: %v\n", err)
}
if runTests {
verbosePrintf("running tests\n")
err = test(filepath.Join(gopath, "src"), gopath, config.Tests...)
if err != nil {
die("running tests failed: %v\n", err)
}
}
}