Files
probo/pkg/deviceagent/update/install_windows.go
Bryan Frimin 712f00f434 Update copyright year
Signed-off-by: Bryan Frimin <bryan@probo.com>
2026-05-26 13:59:17 -07:00

75 lines
2.3 KiB
Go

// Copyright (c) 2026 Probo Inc <hello@getprobo.com>.
//
// Permission to use, copy, modify, and/or distribute this software for any
// purpose with or without fee is hereby granted, provided that the above
// copyright notice and this permission notice appear in all copies.
//
// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH
// REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
// AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT,
// INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
// LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
// OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
// PERFORMANCE OF THIS SOFTWARE.
//go:build windows
package update
import (
"errors"
"fmt"
"os"
)
const oldSuffix = ".old"
// replaceBinary swaps dst with src on Windows.
//
// Windows blocks deletion / replacement of the running .exe but does
// allow renaming a locked .exe out of the way. We:
//
// 1. Stage src as `<dst>.new` (same directory, so the final rename is
// just a metadata update and won't cross volumes).
// 2. Move the running binary to `<dst>.old` (NTFS lets us rename a
// locked exe).
// 3. Move `<dst>.new` into place at `<dst>`.
//
// On the next start the agent's main() calls CleanupAfterRestart to
// best-effort delete `<dst>.old`.
func replaceBinary(dst, src string) error {
staging := dst + ".new"
if err := copyFile(src, staging); err != nil {
return err
}
oldPath := dst + oldSuffix
_ = os.Remove(oldPath)
if err := os.Rename(dst, oldPath); err != nil && !errors.Is(err, os.ErrNotExist) {
_ = os.Remove(staging)
return fmt.Errorf("cannot move running binary aside: %w", err)
}
if err := os.Rename(staging, dst); err != nil {
// Try to roll back the running binary swap.
_ = os.Rename(oldPath, dst)
_ = os.Remove(staging)
return fmt.Errorf("cannot install new binary at %s: %w", dst, err)
}
return nil
}
// CleanupAfterRestart removes the previous-version binary left behind
// by replaceBinary. Best-effort: callers ignore errors, so a still-locked
// `<exePath>.old` is fine and will be retried on the next boot.
func CleanupAfterRestart(exePath string) {
if exePath == "" {
return
}
_ = os.Remove(exePath + oldSuffix)
}