##// END OF EJS Templates
rust-chg: add struct holding information needed to spawn server process...
rust-chg: add struct holding information needed to spawn server process The Locator will handle the initialization of the connection. It will spawn server processes as needed.

File last commit:

r40325:7d3285f7 default
r40325:7d3285f7 default
Show More
locator.rs
126 lines | 3.9 KiB | application/rls-services+xml | RustLexer
// Copyright 2011, 2018 Yuya Nishihara <yuya@tcha.org>
//
// This software may be used and distributed according to the terms of the
// GNU General Public License version 2 or any later version.
//! Utility for locating command-server process.
use std::env;
use std::ffi::{OsStr, OsString};
use std::fs::{self, DirBuilder};
use std::io;
use std::os::unix::ffi::{OsStrExt, OsStringExt};
use std::os::unix::fs::{DirBuilderExt, MetadataExt};
use std::path::{Path, PathBuf};
use std::process;
use std::time::Duration;
use super::procutil;
/// Helper to connect to and spawn a server process.
#[derive(Clone, Debug)]
pub struct Locator {
hg_command: OsString,
current_dir: PathBuf,
env_vars: Vec<(OsString, OsString)>,
process_id: u32,
base_sock_path: PathBuf,
timeout: Duration,
}
impl Locator {
/// Creates locator capturing the current process environment.
///
/// If no `$CHGSOCKNAME` is specified, the socket directory will be
/// created as necessary.
pub fn prepare_from_env() -> io::Result<Locator> {
Ok(Locator {
hg_command: default_hg_command(),
current_dir: env::current_dir()?,
env_vars: env::vars_os().collect(),
process_id: process::id(),
base_sock_path: prepare_server_socket_path()?,
timeout: default_timeout(),
})
}
/// Temporary socket path for this client process.
fn temp_sock_path(&self) -> PathBuf {
let src = self.base_sock_path.as_os_str().as_bytes();
let mut buf = Vec::with_capacity(src.len() + 6);
buf.extend_from_slice(src);
buf.extend_from_slice(format!(".{}", self.process_id).as_bytes());
OsString::from_vec(buf).into()
}
}
/// Determines the server socket to connect to.
///
/// If no `$CHGSOCKNAME` is specified, the socket directory will be created
/// as necessary.
pub fn prepare_server_socket_path() -> io::Result<PathBuf> {
if let Some(s) = env::var_os("CHGSOCKNAME") {
Ok(PathBuf::from(s))
} else {
let mut path = default_server_socket_dir();
create_secure_dir(&path)?;
path.push("server");
Ok(path)
}
}
/// Determines the default server socket path as follows.
///
/// 1. `$XDG_RUNTIME_DIR/chg`
/// 2. `$TMPDIR/chg$UID`
/// 3. `/tmp/chg$UID`
pub fn default_server_socket_dir() -> PathBuf {
// XDG_RUNTIME_DIR should be ignored if it has an insufficient permission.
// https://standards.freedesktop.org/basedir-spec/basedir-spec-latest.html
if let Some(Ok(s)) = env::var_os("XDG_RUNTIME_DIR").map(check_secure_dir) {
let mut path = PathBuf::from(s);
path.push("chg");
path
} else {
let mut path = env::temp_dir();
path.push(format!("chg{}", procutil::get_effective_uid()));
path
}
}
/// Determines the default hg command.
pub fn default_hg_command() -> OsString {
// TODO: maybe allow embedding the path at compile time (or load from hgrc)
env::var_os("CHGHG").or(env::var_os("HG")).unwrap_or(OsStr::new("hg").to_owned())
}
fn default_timeout() -> Duration {
let secs = env::var("CHGTIMEOUT").ok().and_then(|s| s.parse().ok()).unwrap_or(60);
Duration::from_secs(secs)
}
/// Creates a directory which the other users cannot access to.
///
/// If the directory already exists, tests its permission.
fn create_secure_dir<P>(path: P) -> io::Result<()>
where P: AsRef<Path>,
{
DirBuilder::new().mode(0o700).create(path.as_ref()).or_else(|err| {
if err.kind() == io::ErrorKind::AlreadyExists {
check_secure_dir(path).map(|_| ())
} else {
Err(err)
}
})
}
fn check_secure_dir<P>(path: P) -> io::Result<P>
where P: AsRef<Path>,
{
let a = fs::symlink_metadata(path.as_ref())?;
if a.is_dir() && a.uid() == procutil::get_effective_uid() && (a.mode() & 0o777) == 0o700 {
Ok(path)
} else {
Err(io::Error::new(io::ErrorKind::Other, "insecure directory"))
}
}