openethereum/parity/main.rs
Wei Tang a1a002f4da Attempt to graceful shutdown in case of panics (#8999)
* Handle graceful shutdown with unwinding

* Fix a race condition

* Avoid double exit deadlock

* typo: fix docs

* Fix ethkey cli compilation

* Fix all other cases panic_hook::set -> panic_hook::set_abort

* struct fields do not need to be public

* Add comments on why exiting AtomicBool is needed
2018-07-02 11:53:50 +02:00

331 lines
10 KiB
Rust

// Copyright 2015-2018 Parity Technologies (UK) Ltd.
// This file is part of Parity.
// Parity is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// Parity is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with Parity. If not, see <http://www.gnu.org/licenses/>.
//! Ethcore client application.
#![warn(missing_docs)]
extern crate parity;
extern crate ctrlc;
extern crate dir;
extern crate fdlimit;
#[macro_use]
extern crate log;
extern crate panic_hook;
extern crate parking_lot;
#[cfg(windows)] extern crate winapi;
use std::{process, env};
use std::sync::atomic::{AtomicBool, Ordering};
use std::io::{self as stdio, Read, Write};
use std::fs::{remove_file, metadata, File, create_dir_all};
use std::path::PathBuf;
use std::sync::Arc;
use ctrlc::CtrlC;
use dir::default_hypervisor_path;
use fdlimit::raise_fd_limit;
use parity::{start, ExecutionAction};
use parking_lot::{Condvar, Mutex};
fn updates_path(name: &str) -> PathBuf {
let mut dest = PathBuf::from(default_hypervisor_path());
dest.push(name);
dest
}
fn latest_exe_path() -> Option<PathBuf> {
File::open(updates_path("latest")).ok()
.and_then(|mut f| { let mut exe = String::new(); f.read_to_string(&mut exe).ok().map(|_| updates_path(&exe)) })
}
fn set_spec_name_override(spec_name: String) {
if let Err(e) = create_dir_all(default_hypervisor_path())
.and_then(|_| File::create(updates_path("spec_name_override"))
.and_then(|mut f| f.write_all(spec_name.as_bytes())))
{
warn!("Couldn't override chain spec: {} at {:?}", e, updates_path("spec_name_override"));
}
}
fn take_spec_name_override() -> Option<String> {
let p = updates_path("spec_name_override");
let r = File::open(p.clone()).ok()
.and_then(|mut f| { let mut spec_name = String::new(); f.read_to_string(&mut spec_name).ok().map(|_| spec_name) });
let _ = remove_file(p);
r
}
#[cfg(windows)]
fn global_cleanup() {
// We need to cleanup all sockets before spawning another Parity process. This makes sure everything is cleaned up.
// The loop is required because of internal reference counter for winsock dll. We don't know how many crates we use do
// initialize it. There's at least 2 now.
for _ in 0.. 10 {
unsafe { ::winapi::um::winsock2::WSACleanup(); }
}
}
#[cfg(not(windows))]
fn global_init() {}
#[cfg(windows)]
fn global_init() {
// When restarting in the same process this reinits windows sockets.
unsafe {
const WS_VERSION: u16 = 0x202;
let mut wsdata: ::winapi::um::winsock2::WSADATA = ::std::mem::zeroed();
::winapi::um::winsock2::WSAStartup(WS_VERSION, &mut wsdata);
}
}
#[cfg(not(windows))]
fn global_cleanup() {}
// Starts ~/.parity-updates/parity and returns the code it exits with.
fn run_parity() -> Option<i32> {
global_init();
use ::std::ffi::OsString;
let prefix = vec![OsString::from("--can-restart"), OsString::from("--force-direct")];
let res = latest_exe_path().and_then(|exe| process::Command::new(exe)
.args(&(env::args_os().skip(1).chain(prefix.into_iter()).collect::<Vec<_>>()))
.status()
.map(|es| es.code().unwrap_or(128))
.ok()
);
global_cleanup();
res
}
const PLEASE_RESTART_EXIT_CODE: i32 = 69;
#[derive(Debug)]
/// Status used to exit or restart the program.
struct ExitStatus {
/// Whether the program panicked.
panicking: bool,
/// Whether the program should exit.
should_exit: bool,
/// Whether the program should restart.
should_restart: bool,
/// If a restart happens, whether a new chain spec should be used.
spec_name_override: Option<String>,
}
// Run our version of parity.
// Returns the exit error code.
fn main_direct(force_can_restart: bool) -> i32 {
global_init();
let mut conf = {
let args = std::env::args().collect::<Vec<_>>();
parity::Configuration::parse_cli(&args).unwrap_or_else(|e| e.exit())
};
if let Some(spec_override) = take_spec_name_override() {
conf.args.flag_testnet = false;
conf.args.arg_chain = spec_override;
}
let can_restart = force_can_restart || conf.args.flag_can_restart;
// increase max number of open files
raise_fd_limit();
let exit = Arc::new((Mutex::new(ExitStatus {
panicking: false,
should_exit: false,
should_restart: false,
spec_name_override: None
}), Condvar::new()));
// Double panic can happen. So when we lock `ExitStatus` after the main thread is notified, it cannot be locked
// again.
let exiting = Arc::new(AtomicBool::new(false));
let exec = if can_restart {
start(
conf,
{
let e = exit.clone();
let exiting = exiting.clone();
move |new_chain: String| {
if !exiting.swap(true, Ordering::SeqCst) {
*e.0.lock() = ExitStatus {
panicking: false,
should_exit: true,
should_restart: true,
spec_name_override: Some(new_chain),
};
e.1.notify_all();
}
}
},
{
let e = exit.clone();
let exiting = exiting.clone();
move || {
if !exiting.swap(true, Ordering::SeqCst) {
*e.0.lock() = ExitStatus {
panicking: false,
should_exit: true,
should_restart: true,
spec_name_override: None,
};
e.1.notify_all();
}
}
}
)
} else {
trace!(target: "mode", "Not hypervised: not setting exit handlers.");
start(conf, move |_| {}, move || {})
};
let res = match exec {
Ok(result) => match result {
ExecutionAction::Instant(Some(s)) => { println!("{}", s); 0 },
ExecutionAction::Instant(None) => 0,
ExecutionAction::Running(client) => {
panic_hook::set_with({
let e = exit.clone();
let exiting = exiting.clone();
move || {
if !exiting.swap(true, Ordering::SeqCst) {
*e.0.lock() = ExitStatus {
panicking: true,
should_exit: true,
should_restart: false,
spec_name_override: None,
};
e.1.notify_all();
}
}
});
CtrlC::set_handler({
let e = exit.clone();
let exiting = exiting.clone();
move || {
if !exiting.swap(true, Ordering::SeqCst) {
*e.0.lock() = ExitStatus {
panicking: false,
should_exit: true,
should_restart: false,
spec_name_override: None,
};
e.1.notify_all();
}
}
});
// Wait for signal
let mut lock = exit.0.lock();
if !lock.should_exit {
let _ = exit.1.wait(&mut lock);
}
client.shutdown();
if lock.should_restart {
if let Some(ref spec_name) = lock.spec_name_override {
set_spec_name_override(spec_name.clone());
}
PLEASE_RESTART_EXIT_CODE
} else {
if lock.panicking {
1
} else {
0
}
}
},
},
Err(err) => {
writeln!(&mut stdio::stderr(), "{}", err).expect("StdErr available; qed");
1
},
};
global_cleanup();
res
}
fn println_trace_main(s: String) {
if env::var("RUST_LOG").ok().and_then(|s| s.find("main=trace")).is_some() {
println!("{}", s);
}
}
#[macro_export]
macro_rules! trace_main {
($arg:expr) => (println_trace_main($arg.into()));
($($arg:tt)*) => (println_trace_main(format!("{}", format_args!($($arg)*))));
}
fn main() {
panic_hook::set_abort();
// assuming the user is not running with `--force-direct`, then:
// if argv[0] == "parity" and this executable != ~/.parity-updates/parity, run that instead.
let force_direct = std::env::args().any(|arg| arg == "--force-direct");
let exe = std::env::current_exe().ok();
let development = exe.as_ref().and_then(|p| p.parent().and_then(|p| p.parent()).and_then(|p| p.file_name()).map(|n| n == "target")).unwrap_or(false);
let same_name = exe.as_ref().map(|p| p.file_stem().map_or(false, |s| s == "parity") && p.extension().map_or(true, |x| x == "exe")).unwrap_or(false);
trace_main!("Starting up {} (force-direct: {}, development: {}, same-name: {})", std::env::current_exe().map(|x| format!("{}", x.display())).unwrap_or("<unknown>".to_owned()), force_direct, development, same_name);
if !force_direct && !development && same_name {
// looks like we're not running ~/.parity-updates/parity when the user is expecting otherwise.
// Everything run inside a loop, so we'll be able to restart from the child into a new version seamlessly.
loop {
// If we fail to run the updated parity then fallback to local version.
let latest_exe = latest_exe_path();
let have_update = latest_exe.as_ref().map_or(false, |p| p.exists());
let is_non_updated_current = exe.as_ref().map_or(false, |exe| latest_exe.as_ref().map_or(false, |lexe| exe.canonicalize().ok() != lexe.canonicalize().ok()));
let update_is_newer = match (
latest_exe.as_ref()
.and_then(|p| metadata(p.as_path()).ok())
.and_then(|m| m.modified().ok()),
exe.as_ref()
.and_then(|p| metadata(p.as_path()).ok())
.and_then(|m| m.modified().ok())
) {
(Some(latest_exe_time), Some(this_exe_time)) if latest_exe_time > this_exe_time => true,
_ => false,
};
trace_main!("Starting... (have-update: {}, non-updated-current: {}, update-is-newer: {})", have_update, is_non_updated_current, update_is_newer);
let exit_code = if have_update && is_non_updated_current && update_is_newer {
trace_main!("Attempting to run latest update ({})...", latest_exe.as_ref().expect("guarded by have_update; latest_exe must exist for have_update; qed").display());
run_parity().unwrap_or_else(|| { trace_main!("Falling back to local..."); main_direct(true) })
} else {
trace_main!("No latest update. Attempting to direct...");
main_direct(true)
};
trace_main!("Latest exited with {}", exit_code);
if exit_code != PLEASE_RESTART_EXIT_CODE {
trace_main!("Quitting...");
process::exit(exit_code);
}
trace_main!("Rerunning...");
}
} else {
trace_main!("Running direct");
// Otherwise, we're presumably running the version we want. Just run and fall-through.
process::exit(main_direct(false));
}
}