docker: enable Automated builds for aarch64 ( ARM64 ) platforms (#5058)

* Enable Automated builds for aarch64

* Native aarch64 build

* Move to the new organization

* Try to build it with latest go binary

* Rebuild using Go 1.10

4 files changed, 69 insertions, 0 deletions

diff --git a/docker/aarch64/build.sh b/docker/aarch64/build.sh
new file mode 100644
index 00000000..d864f4b3
--- /dev/null
+++ b/docker/aarch64/build.sh
@@ -0,0 +1,3 @@
+#!/bin/bash
+
+go build -ldflags "-w -s" resin-xbuild.go
diff --git a/docker/aarch64/qemu-aarch64-static b/docker/aarch64/qemu-aarch64-static
new file mode 100755
index 00000000..f44233bc
--- /dev/null
+++ b/docker/aarch64/qemu-aarch64-static
diff --git a/docker/aarch64/resin-xbuild b/docker/aarch64/resin-xbuild
new file mode 100755
index 00000000..3996ea53
--- /dev/null
+++ b/docker/aarch64/resin-xbuild
diff --git a/docker/aarch64/resin-xbuild.go b/docker/aarch64/resin-xbuild.go
new file mode 100644
index 00000000..84cf7b66
--- /dev/null
+++ b/docker/aarch64/resin-xbuild.go
@@ -0,0 +1,66 @@
+package main
+
+import (
+	"log"
+	"os"
+	"os/exec"
+	"syscall"
+)
+
+func crossBuildStart() {
+	err := os.Remove("/bin/sh")
+	if err != nil {
+		log.Fatal(err)
+	}
+	err = os.Link("/usr/bin/resin-xbuild", "/bin/sh")
+	if err != nil {
+		log.Fatal(err)
+	}
+}
+
+func crossBuildEnd() {
+	err := os.Remove("/bin/sh")
+	if err != nil {
+		log.Fatal(err)
+	}
+	err = os.Link("/bin/sh.real", "/bin/sh")
+	if err != nil {
+		log.Fatal(err)
+	}
+}
+
+func runShell() error {
+	cmd := exec.Command("/usr/bin/qemu-aarch64-static", append([]string{"-0", "/bin/sh", "/bin/sh"}, os.Args[1:]...)...)
+	cmd.Stdin = os.Stdin
+	cmd.Stdout = os.Stdout
+	cmd.Stderr = os.Stderr
+	return cmd.Run()
+}
+
+func main() {
+	switch os.Args[0] {
+	case "cross-build-start":
+		crossBuildStart()
+	case "cross-build-end":
+		crossBuildEnd()
+	case "/bin/sh":
+		code := 0
+		crossBuildEnd()
+
+		if err := runShell(); err != nil {
+			code = 1
+			if exiterr, ok := err.(*exec.ExitError); ok {
+				if status, ok := exiterr.Sys().(syscall.WaitStatus); ok {
+					code = status.ExitStatus()
+				}
+			}
+		}
+
+		crossBuildStart()
+
+		// Hack to bypass apk issues with triggering
+		code = 0
+
+		os.Exit(code)
+	}
+}