Files
selfpost/internal/postfix/write.go
T
mix 8ce050ef7f release: 0.1.0: Phases 0-11: panel, Postfix/DKIM, milter, backup, Docker image
Initial feature-complete implementation of the v1.0 specification (phases 0-11 of `docs/implementation-plan.md`).
Added:
  - Panel (Go, single static binary) with SQLite persistence, one-time
  - Domain management with per-domain DKIM (RSA-2048, generated in pure Go) and
  - Application (sender identity) management: SASL credentials via `sasldb2`,
  - Full Postfix relay config generated from env at container start: SMTPS 465,
  - Journal milter (pure Go, `go-milter`) recording every send to `send_log`;
  … (6 more in CHANGELOG)

Full detail: CHANGELOG.md (0.1.0).
2026-09-22 15:24:51 +03:00

48 lines
1.2 KiB
Go

package postfix
import (
"fmt"
"os"
"path/filepath"
)
// writeFileAtomic writes data to path via a temp file in the same directory
// followed by a rename, so a concurrent Postfix reload only ever sees the
// complete old or new map, never a partial write (spec 7.6.4). It mirrors the
// same primitive used for the OpenDKIM tables.
func writeFileAtomic(path string, data []byte, perm os.FileMode) error {
dir := filepath.Dir(path)
tmp, err := os.CreateTemp(dir, ".tmp-*")
if err != nil {
return fmt.Errorf("create temp in %s: %w", dir, err)
}
tmpName := tmp.Name()
cleanup := true
defer func() {
if cleanup {
_ = os.Remove(tmpName)
}
}()
if _, err := tmp.Write(data); err != nil {
tmp.Close()
return fmt.Errorf("write temp %s: %w", tmpName, err)
}
if err := tmp.Chmod(perm); err != nil {
tmp.Close()
return fmt.Errorf("chmod temp %s: %w", tmpName, err)
}
if err := tmp.Sync(); err != nil {
tmp.Close()
return fmt.Errorf("sync temp %s: %w", tmpName, err)
}
if err := tmp.Close(); err != nil {
return fmt.Errorf("close temp %s: %w", tmpName, err)
}
if err := os.Rename(tmpName, path); err != nil {
return fmt.Errorf("rename %s -> %s: %w", tmpName, path, err)
}
cleanup = false
return nil
}