tools: daemon: rename some structs

Reloadable resources are now 'Reloadable' instead of
'ReexecContinue'.

The struct handling the reload is a 'Reloader', not a
'ReexecStore'.

Signed-off-by: Wolfgang Bumiller <w.bumiller@proxmox.com>
This commit is contained in:
Wolfgang Bumiller 2019-03-18 13:44:37 +01:00
parent 14ed3eb57c
commit 3aa2dbc857

View File

@ -6,6 +6,7 @@ use std::os::unix::ffi::OsStrExt;
use std::panic::UnwindSafe;
use failure::*;
use nix::sys::signalfd::siginfo;
use tokio::prelude::*;
use crate::tools::fd_change_cloexec;
@ -16,14 +17,14 @@ pub type BoxedStoreFunc = Box<dyn Fn() -> Result<String, Error> + UnwindSafe + S
/// Helper trait to "store" something in the environment to be re-used after re-executing the
/// service on a reload.
pub trait ReexecContinue: Sized {
pub trait Reloadable: Sized {
fn restore(var: &str) -> Result<Self, Error>;
fn get_store_func(&self) -> BoxedStoreFunc;
}
/// Manages things to be stored and reloaded upon reexec.
/// Anything which should be restorable should be instantiated via this struct's `restore` method,
pub struct ReexecStore {
pub struct Reloader {
pre_exec: Vec<PreExecEntry>,
}
@ -34,7 +35,7 @@ struct PreExecEntry {
store_fn: BoxedStoreFunc,
}
impl ReexecStore {
impl Reloader {
pub fn new() -> Self {
Self {
pre_exec: Vec::new(),
@ -47,7 +48,7 @@ impl ReexecStore {
/// Values created via this method will be remembered for later re-execution.
pub fn restore<T, F>(&mut self, name: &'static str, or_create: F) -> Result<T, Error>
where
T: ReexecContinue,
T: Reloadable,
F: FnOnce() -> Result<T, Error>,
{
let res = match std::env::var(name) {
@ -120,12 +121,12 @@ impl ReexecStore {
}
/// Provide a default signal handler for daemons (daemon & proxy).
/// When the first `SIGHUP` is received, the `reexec_store`'s `fork_restart` method will be
/// When the first `SIGHUP` is received, the `reloader`'s `fork_restart` method will be
/// triggered. Any further `SIGHUP` is "passed through".
pub fn default_signalfd_stream<F>(
reexec_store: ReexecStore,
reloader: Reloader,
before_reload: F,
) -> Result<impl Stream<Item = nix::sys::signalfd::siginfo, Error = Error>, Error>
) -> Result<impl Stream<Item = siginfo, Error = Error>, Error>
where
F: FnOnce() -> Result<(), Error>,
{
@ -137,7 +138,7 @@ where
sigprocmask(SigmaskHow::SIG_BLOCK, Some(&sigs), None)?;
let sigfdstream = SignalFd::new(&sigs)?;
let mut reexec_store = Some(reexec_store);
let mut reloader = Some(reloader);
let mut before_reload = Some(before_reload);
Ok(sigfdstream
@ -148,12 +149,12 @@ where
if si.ssi_signo == Signal::SIGHUP as u32 {
// The firs time this happens we will try to start a new process which should take
// over.
if let Some(reexec_store) = reexec_store.take() {
if let Some(reloader) = reloader.take() {
if let Err(e) = (before_reload.take().unwrap())() {
return Some(Err(e));
}
match reexec_store.fork_restart() {
match reloader.fork_restart() {
Ok(_) => return None,
Err(e) => return Some(Err(e)),
}
@ -172,7 +173,7 @@ where
}
// For now all we need to do is store and reuse a tcp listening socket:
impl ReexecContinue for tokio::net::TcpListener {
impl Reloadable for tokio::net::TcpListener {
// NOTE: The socket must not be closed when the store-function is called:
// FIXME: We could become "independent" of the TcpListener and its reference to the file
// descriptor by `dup()`ing it (and check if the listener still exists via kcmp()?)