Add executable to install with

main.go

+package main
+
+import (
+	"archive/tar"
+	"bufio"
+	"bytes"
+	"compress/bzip2"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"net/http"
+	"os"
+	"path"
+	"regexp"
+	"runtime"
+	"strings"
+	"time"
+
+	"github.com/richardwilkes/toolbox/atexit"
+	"github.com/richardwilkes/toolbox/cmdline"
+	"github.com/richardwilkes/toolbox/xio"
+)
+
+const desiredCEFVersion = "3.3538.1852.gcb937fc"
+
+var (
+	cefVersionRegex = regexp.MustCompile(`^\s*#define\s+CEF_VERSION\s+"(\d+\.\d+\.\d+\.\w+)"\s*$`)
+	installPrefix   = "/usr/local/cef"
+	cefPlatform     string
+)
+
+func main() {
+	cmdline.CopyrightYears = "2018"
+	cmdline.CopyrightHolder = "Richard A. Wilkes"
+	cmdline.AppIdentifier = "com.trollworks.cef"
+	cl := cmdline.New(true)
+	cl.Description = "Downloads and installs the headers and libraries necessary use the github.com/richardwilkes/cef/cef package."
+	var needInstall bool
+	cl.NewBoolOption(&needInstall).SetSingle('f').SetName("force").SetUsage("Force an install")
+	cl.Parse(os.Args[1:])
+
+	switch runtime.GOOS {
+	case "darwin":
+		cefPlatform = "macosx64"
+	case "windows":
+		if os.Getenv("MSYSTEM") != "MINGW64" {
+			fmt.Println("Windows is only supported through the use of MINGW64")
+			atexit.Exit(1)
+		}
+		cefPlatform = "windows64"
+		installPrefix = path.Join(path.Dir(os.Getenv("MINGW_PREFIX")), installPrefix)
+	default:
+		fmt.Println("Unsupported OS: ", runtime.GOOS)
+		atexit.Exit(1)
+	}
+
+	if !needInstall {
+		var existingCEFVersion string
+		if f, err := os.Open(path.Join(installPrefix, "include/cef_version.h")); err == nil {
+			s := bufio.NewScanner(f)
+			for s.Scan() {
+				line := s.Text()
+				if result := cefVersionRegex.FindStringSubmatch(line); len(result) == 2 {
+					existingCEFVersion = result[1]
+					break
+				}
+			}
+			xio.CloseIgnoringErrors(f)
+		}
+		needInstall = existingCEFVersion != desiredCEFVersion
+	}
+
+	if needInstall {
+		fmt.Printf("Installing into %s...\n", installPrefix)
+		if err := os.RemoveAll(installPrefix); err != nil {
+			fmt.Printf("Unable to remove old installation at %s\n", installPrefix)
+			fmt.Println(err)
+			fmt.Println("You may need to run this as root.")
+			atexit.Exit(1)
+		}
+		createDir(installPrefix, 0755)
+		untar(bytes.NewBuffer(downloadAndUncompressArchive()))
+		if runtime.GOOS == "windows" {
+			dir := path.Join(path.Dir(os.Getenv("MINGW_PREFIX")), "lib/pkgconfig")
+			createDir(dir, 0755)
+			name := path.Join(dir, "cef.pc")
+			f, err := os.Create(name)
+			checkFileError(err, "create", name)
+			_, err = fmt.Fprintf(f, `Name: cef
+Description: Chromium Embedded Framework
+Version: %[1]s
+
+Requires:
+Libs: -L%[2]s/Release -lcef
+Cflags: -I%[2]s
+`, desiredCEFVersion, installPrefix)
+			checkFileError(err, "write", name)
+			checkFileError(f.Close(), "write", name)
+		}
+	}
+
+	atexit.Exit(0)
+}
+
+func createDir(dir string, mode os.FileMode) {
+	if err := os.MkdirAll(dir, mode); err != nil {
+		fmt.Println(err)
+		fmt.Println("You may need to run this as root.")
+		atexit.Exit(1)
+	}
+}
+
+func checkFileError(err error, op, name string) {
+	if err != nil {
+		fmt.Printf("Unable to %s file %s\n", op, name)
+		fmt.Println(err)
+		atexit.Exit(1)
+	}
+}
+
+func archiveName() string {
+	return fmt.Sprintf("cef_binary_%s_%s_minimal", desiredCEFVersion, cefPlatform)
+}
+
+func downloadAndUncompressArchive() []byte {
+	client := http.Client{Timeout: 10 * time.Minute}
+	url := fmt.Sprintf("http://opensource.spotify.com/cefbuilds/%s.tar.bz2", archiveName())
+	fmt.Println("  Downloading...")
+	resp, err := client.Get(url)
+	if err != nil {
+		fmt.Printf("Unable to download CEF archive at %s\n", url)
+		fmt.Println(err)
+		atexit.Exit(1)
+	}
+	buffer, err := ioutil.ReadAll(resp.Body)
+	xio.CloseIgnoringErrors(resp.Body)
+	if err != nil {
+		fmt.Printf("Unable to download CEF archive at %s\n", url)
+		fmt.Println(err)
+		atexit.Exit(1)
+	}
+	if resp.StatusCode > 299 {
+		fmt.Printf("Unable to download CEF archive at %s\n", url)
+		fmt.Printf("Status: %s\n", resp.Status)
+		atexit.Exit(1)
+	}
+	fmt.Println("  Uncompressing...")
+	buffer, err = ioutil.ReadAll(bzip2.NewReader(bytes.NewReader(buffer)))
+	if err != nil {
+		fmt.Printf("Unable to uncompress CEF archive from %s\n", url)
+		fmt.Println(err)
+		atexit.Exit(1)
+	}
+	return buffer
+}
+
+func untar(in io.Reader) {
+	prefix := archiveName()
+	fmt.Println("  Unarchiving...")
+	r := tar.NewReader(in)
+	for {
+		h, err := r.Next()
+		if err != nil {
+			if err == io.EOF {
+				break
+			}
+			fmt.Println("Unable to read tar entry from archive")
+			fmt.Println(err)
+			atexit.Exit(1)
+		}
+		name := strings.Trim(strings.TrimPrefix(h.Name, prefix), "/")
+		if name != "" && !strings.Contains(name, "..") {
+			name = path.Join(installPrefix, name)
+			switch h.Typeflag {
+			case tar.TypeDir:
+				createDir(name, os.FileMode(h.Mode|0555))
+			case tar.TypeReg:
+				buffer, err := ioutil.ReadAll(r)
+				checkFileError(err, "read archive data for", name)
+				checkFileError(ioutil.WriteFile(name, buffer, os.FileMode(h.Mode|0444)), "write", name)
+			default:
+				fmt.Printf("Unexpected type flag: %d\n", h.Typeflag)
+				atexit.Exit(1)
+			}
+		}
+	}
+}