define-alpine-the-sequel/qemu.ts

import { cp, mkdir, mkdtemp, rm } from "node:fs/promises";
import { tmpdir } from "node:os";
import path, { join } from "node:path";
import { canAccess, execFile } from "./helpers/better-api.js";
import { sudoChownToRunningUser } from "./helpers/sudo.js";

export async function runQemu(
  squashfs: string,
  kernel: { initramfs: string; vmlinuz: string },
  { graphic, noShutdown }: { graphic?: boolean; noShutdown?: boolean } = {
    graphic: true,
    noShutdown: false,
  }
) {
  await sudoChownToRunningUser(kernel.initramfs);
  await sudoChownToRunningUser(kernel.vmlinuz);
  await sudoChownToRunningUser(squashfs);
  const tmp = await mkdtemp(path.join(tmpdir(), "define-alpine-qemu-"));
  try {
    // const disk = path.join(tmp, "tmp.ext4");
    const disk = "tmp.ext4";
    if (!(await canAccess(disk))) {
      await execFile("fallocate", ["--length", "1G", disk]);
      await execFile("mkfs.ext4", ["-F", disk]);
    }
    {
      const mountpoint = join(tmp, "persist-mount");
      await mkdir(mountpoint);
      await execFile("sudo", ["mount", disk, mountpoint]);
      try {
        await execFile("sudo", [
          "cp",
          squashfs,
          join(mountpoint, "current.squashfs"),
        ]);
      } finally {
        await execFile("sudo", ["umount", mountpoint]);
      }
    }

    let kernelAppend = [
      "root=/dev/sda",
      "rootfstype=ext4",
      "modules=ext4",
      "quiet",
      "init=/sbin/runit-init",
    ];
    let qemuAppend: string[] = [];

    if (!graphic) {
      kernelAppend.push("console=ttyS0");
      qemuAppend.push("-nographic");
    }
    if (noShutdown) qemuAppend.push("-no-shutdown");

    // sudo chown root:$(id -u) -R boot/ && sudo chmod g+rw -R boot/
    await execFile("qemu-system-x86_64", [
      "-enable-kvm",
      "-m",
      "2048",
      // "-drive",
      // `file=${squashfs},media=disk,format=raw`,
      "-drive",
      `file=${disk},media=disk,format=raw`,
      "-net",
      "nic,model=virtio-net-pci",
      "-net",
      "user,hostfwd=tcp:127.0.0.1:8080-:80",
      "-kernel",
      kernel.vmlinuz,
      "-initrd",
      kernel.initramfs,
      "-append",
      kernelAppend.join(" "),
      ...qemuAppend,
    ]);
    // -append "root=/dev/sda rootfstype=squashfs modules=ext4 quiet init=/sbin/runit-init $append" $qemuappend
  } finally {
    await rm(tmp, { recursive: true, force: true });
  }
}

await runQemu(
  "artifacts/image.squashfs",
  {
    initramfs: "artifacts/kernel/initramfs",
    vmlinuz: "artifacts/kernel/vmlinuz",
  },
  { graphic: true, noShutdown: true }
);