dearsky/numa
1
0
Fork 0
Code Issues 10 Pull Requests 1 Actions Packages Projects Releases 25 Wiki Activity

fix(linux): atomic binary copy + restart instead of start on re-install

Browse Source 
Re-install failed with ETXTBSY (Text file busy) because std::fs::copy
can't overwrite a binary that's currently being executed by the
running service. Switch to copy-then-rename: write the new binary to
/usr/local/bin/numa.new, then rename over /usr/local/bin/numa. Rename
swaps the path while the running process keeps the old inode alive,
so DNS keeps serving from the previous binary until restart.

Bump systemctl start to restart so the new binary actually loads on
re-install (start is a no-op when the unit is already active, which
would silently leave the old binary running).

Locally verified the full CI sequence: install → curl → reinstall →
curl → uninstall → curl-fails. All three assertions pass.
This commit is contained in:
Razvan Dimescu
2026-04-18 12:12:11 +03:00
parent e19505aa95
commit 067195f2ab
1 changed files with 14 additions and 4 deletions
Download Patch File Download Diff File Expand all files Collapse all files

18
src/system_dns.rs
View File

@@ -1708,10 +1708,18 @@ fn install_service_binary_linux() -> Result<std::path::PathBuf, String> {
std::fs::create_dir_all(parent)
.map_err(|e| format!("failed to create {}: {}", parent.display(), e))?;
}
std::fs::copy(&src, &dst).map_err(|e| {
// Atomic replace via temp + rename. Plain copy fails with ETXTBSY when
// re-installing while the service is running the previous binary —
// rename swaps the path while the running process keeps the old inode.
let tmp = dst.with_extension("new");
std::fs::copy(&src, &tmp).map_err(|e| {
format!("failed to copy {} -> {}: {}", src.display(), tmp.display(), e)
})?;
std::fs::rename(&tmp, &dst).map_err(|e| {
let _ = std::fs::remove_file(&tmp);
format!(
"failed to copy {} -> {}: {}",
src.display(),
"failed to rename {} -> {}: {}",
tmp.display(),
dst.display(),
e
)
@@ -1734,7 +1742,9 @@ fn install_service_linux() -> Result<(), String> {
eprintln!(" warning: failed to configure system DNS: {}", e);
}
run_systemctl(&["start", "numa"])?;
// restart, not start: on re-install the service is already running
// the previous binary; restart picks up the new one.
run_systemctl(&["restart", "numa"])?;
eprintln!(" Service installed and started.");
eprintln!(" Numa will auto-start on boot and restart if killed.");