66 lines
2.2 KiB
Go
66 lines
2.2 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 (
|
|
"fmt"
|
|
"os"
|
|
)
|
|
|
|
// replaceBinary replaces the file at dst with src.
|
|
//
|
|
// On Unix the rename is atomic: the kernel keeps the running
|
|
// executable mapped via its inode, while the destination path now
|
|
// points at the new binary on disk. The next exec (after the
|
|
// supervisor restarts the process) loads the new code.
|
|
//
|
|
// We try a same-directory rename first, then fall back to a
|
|
// copy + atomic rename when src and dst live on different
|
|
// filesystems (e.g. when /tmp is a tmpfs separate from /usr/local/bin).
|
|
func replaceBinary(dst, src string) error {
|
|
if err := os.Chmod(src, 0o755); err != nil {
|
|
return fmt.Errorf("cannot chmod new binary: %w", err)
|
|
}
|
|
|
|
if err := os.Rename(src, dst); err == nil {
|
|
return nil
|
|
}
|
|
|
|
// Cross-filesystem fallback: copy into <dst>.new, fsync,
|
|
// then rename within the destination directory.
|
|
staging := dst + ".new"
|
|
if err := copyFile(src, staging); err != nil {
|
|
return err
|
|
}
|
|
|
|
if err := os.Chmod(staging, 0o755); err != nil {
|
|
_ = os.Remove(staging)
|
|
return fmt.Errorf("cannot chmod staged binary: %w", err)
|
|
}
|
|
|
|
if err := os.Rename(staging, dst); err != nil {
|
|
_ = os.Remove(staging)
|
|
return fmt.Errorf("cannot atomically replace %s: %w", dst, err)
|
|
}
|
|
|
|
return nil
|
|
}
|
|
|
|
// CleanupAfterRestart removes any leftover .old binary from a
|
|
// previous Windows-style swap. On Unix this is a no-op.
|
|
func CleanupAfterRestart(_ string) {}
|