xgo/xgo.go

121 lines
4.1 KiB
Go

// Go CGO cross compiler
// Copyright (c) 2014 Péter Szilágyi. All rights reserved.
//
// Released under the MIT license.
// Wrapper around the GCO cross compiler docker container.
package main
import (
"bytes"
"flag"
"fmt"
"log"
"os"
"os/exec"
"strings"
)
// Cross compilation docker containers
var dockerBase = "karalabe/xgo-base"
var dockerDist = "karalabe/xgo-"
// Command line arguments to fine tune the compilation
var goVersion = flag.String("go", "latest", "Go release to use for cross compilation")
var inPackage = flag.String("pkg", "", "Sub-package to build if not root import")
var outPrefix = flag.String("out", "", "Prefix to use for output naming (empty = package name)")
var srcRemote = flag.String("remote", "", "Version control remote repository to build")
var srcBranch = flag.String("branch", "", "Version control branch to build")
var crossDeps = flag.String("deps", "", "CGO dependencies (configure/make based archives)")
var targets = flag.String("targets", "*/*", "Comma separated targets to build for")
// Command line arguments to pass to go build
var buildVerbose = flag.Bool("v", false, "Print the names of packages as they are compiled")
var buildSteps = flag.Bool("x", false, "Print the command as executing the builds")
var buildRace = flag.Bool("race", false, "Enable data race detection (supported only on amd64)")
func main() {
flag.Parse()
// Ensure docker is available
if err := checkDocker(); err != nil {
log.Fatalf("Failed to check docker installation: %v.", err)
}
// Validate the command line arguments
if len(flag.Args()) != 1 {
log.Fatalf("Usage: %s [options] <go import path>", os.Args[0])
}
// Check that all required images are available
found, err := checkDockerImage(dockerDist + *goVersion)
switch {
case err != nil:
log.Fatalf("Failed to check docker image availability: %v.", err)
case !found:
fmt.Println("not found!")
if err := pullDockerImage(dockerDist + *goVersion); err != nil {
log.Fatalf("Failed to pull docker image from the registry: %v.", err)
}
default:
fmt.Println("found.")
}
// Cross compile the requested package into the local folder
if err := compile(flag.Args()[0], *srcRemote, *srcBranch, *inPackage, *crossDeps, *outPrefix, *buildVerbose, *buildSteps, *buildRace, strings.Split(*targets, ",")); err != nil {
log.Fatalf("Failed to cross compile package: %v.", err)
}
}
// Checks whether a docker installation can be found and is functional.
func checkDocker() error {
fmt.Println("Checking docker installation...")
if err := run(exec.Command("docker", "version")); err != nil {
return err
}
fmt.Println()
return nil
}
// Checks whether a required docker image is available locally.
func checkDockerImage(image string) (bool, error) {
fmt.Printf("Checking for required docker image %s... ", image)
out, err := exec.Command("docker", "images", "--no-trunc").Output()
if err != nil {
return false, err
}
return bytes.Contains(out, []byte(image)), nil
}
// Pulls an image from the docker registry.
func pullDockerImage(image string) error {
fmt.Printf("Pulling %s from docker registry...\n", image)
return run(exec.Command("docker", "pull", image))
}
// Cross compiles a requested package into the current working directory.
func compile(repo string, remote string, branch string, pack string, deps string, prefix string, verbose bool, steps bool, race bool, targets []string) error {
folder, err := os.Getwd()
if err != nil {
log.Fatalf("Failed to retrieve the working directory: %v.", err)
}
fmt.Printf("Cross compiling %s...\n", repo)
return run(exec.Command("docker", "run",
"-v", folder+":/build",
"-e", "REPO_REMOTE="+remote,
"-e", "REPO_BRANCH="+branch,
"-e", "PACK="+pack,
"-e", "DEPS="+deps,
"-e", "OUT="+prefix,
"-e", fmt.Sprintf("FLAG_V=%v", verbose),
"-e", fmt.Sprintf("FLAG_X=%v", steps),
"-e", fmt.Sprintf("FLAG_RACE=%v", race),
"-e", "TARGETS="+strings.Replace(strings.Join(targets, " "), "*", ".", -1),
dockerDist+*goVersion, repo))
}
// Executes a command synchronously, redirecting its output to stdout.
func run(cmd *exec.Cmd) error {
cmd.Stdout = os.Stdout
cmd.Stderr = os.Stderr
return cmd.Run()
}