rust/src/bootstrap/util.rs
2016-09-12 21:22:15 -07:00

175 lines
5.8 KiB
Rust

// Copyright 2015 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.
//! Various utility functions used throughout rustbuild.
//!
//! Simple things like testing the various filesystem operations here and there,
//! not a lot of interesting happenings here unfortunately.
use std::env;
use std::ffi::OsString;
use std::fs;
use std::path::{Path, PathBuf};
use std::process::Command;
use filetime::FileTime;
/// Returns the `name` as the filename of a static library for `target`.
pub fn staticlib(name: &str, target: &str) -> String {
if target.contains("windows") {
format!("{}.lib", name)
} else {
format!("lib{}.a", name)
}
}
/// Returns the last-modified time for `path`, or zero if it doesn't exist.
pub fn mtime(path: &Path) -> FileTime {
fs::metadata(path).map(|f| {
FileTime::from_last_modification_time(&f)
}).unwrap_or(FileTime::zero())
}
/// Copies a file from `src` to `dst`, attempting to use hard links and then
/// falling back to an actually filesystem copy if necessary.
pub fn copy(src: &Path, dst: &Path) {
let res = fs::hard_link(src, dst);
let res = res.or_else(|_| fs::copy(src, dst).map(|_| ()));
if let Err(e) = res {
panic!("failed to copy `{}` to `{}`: {}", src.display(),
dst.display(), e)
}
}
/// Copies the `src` directory recursively to `dst`. Both are assumed to exist
/// when this function is called.
pub fn cp_r(src: &Path, dst: &Path) {
for f in t!(fs::read_dir(src)) {
let f = t!(f);
let path = f.path();
let name = path.file_name().unwrap();
let dst = dst.join(name);
if t!(f.file_type()).is_dir() {
let _ = fs::remove_dir_all(&dst);
t!(fs::create_dir(&dst));
cp_r(&path, &dst);
} else {
let _ = fs::remove_file(&dst);
copy(&path, &dst);
}
}
}
/// Copies the `src` directory recursively to `dst`. Both are assumed to exist
/// when this function is called. Unwanted files or directories can be skipped
/// by returning `false` from the filter function.
pub fn cp_filtered<F: Fn(&Path) -> bool>(src: &Path, dst: &Path, filter: &F) {
// Inner function does the actual work
fn recurse<F: Fn(&Path) -> bool>(src: &Path, dst: &Path, relative: &Path, filter: &F) {
for f in t!(fs::read_dir(src)) {
let f = t!(f);
let path = f.path();
let name = path.file_name().unwrap();
let dst = dst.join(name);
let relative = relative.join(name);
// Only copy file or directory if the filter function returns true
if filter(&relative) {
if t!(f.file_type()).is_dir() {
let _ = fs::remove_dir_all(&dst);
t!(fs::create_dir(&dst));
recurse(&path, &dst, &relative, filter);
} else {
let _ = fs::remove_file(&dst);
copy(&path, &dst);
}
}
}
}
// Immediately recurse with an empty relative path
recurse(src, dst, Path::new(""), filter)
}
/// Given an executable called `name`, return the filename for the
/// executable for a particular target.
pub fn exe(name: &str, target: &str) -> String {
if target.contains("windows") {
format!("{}.exe", name)
} else {
name.to_string()
}
}
/// Returns whether the file name given looks like a dynamic library.
pub fn is_dylib(name: &str) -> bool {
name.ends_with(".dylib") || name.ends_with(".so") || name.ends_with(".dll")
}
/// Returns the corresponding relative library directory that the compiler's
/// dylibs will be found in.
pub fn libdir(target: &str) -> &'static str {
if target.contains("windows") {"bin"} else {"lib"}
}
/// Adds a list of lookup paths to `cmd`'s dynamic library lookup path.
pub fn add_lib_path(path: Vec<PathBuf>, cmd: &mut Command) {
let mut list = dylib_path();
for path in path {
list.insert(0, path);
}
cmd.env(dylib_path_var(), t!(env::join_paths(list)));
}
/// Returns whether `dst` is up to date given that the file or files in `src`
/// are used to generate it.
///
/// Uses last-modified time checks to verify this.
pub fn up_to_date(src: &Path, dst: &Path) -> bool {
let threshold = mtime(dst);
let meta = match fs::metadata(src) {
Ok(meta) => meta,
Err(e) => panic!("source {:?} failed to get metadata: {}", src, e),
};
if meta.is_dir() {
dir_up_to_date(src, &threshold)
} else {
FileTime::from_last_modification_time(&meta) <= threshold
}
}
fn dir_up_to_date(src: &Path, threshold: &FileTime) -> bool {
t!(fs::read_dir(src)).map(|e| t!(e)).all(|e| {
let meta = t!(e.metadata());
if meta.is_dir() {
dir_up_to_date(&e.path(), threshold)
} else {
FileTime::from_last_modification_time(&meta) < *threshold
}
})
}
/// Returns the environment variable which the dynamic library lookup path
/// resides in for this platform.
pub fn dylib_path_var() -> &'static str {
if cfg!(target_os = "windows") {
"PATH"
} else if cfg!(target_os = "macos") {
"DYLD_LIBRARY_PATH"
} else {
"LD_LIBRARY_PATH"
}
}
/// Parses the `dylib_path_var()` environment variable, returning a list of
/// paths that are members of this lookup path.
pub fn dylib_path() -> Vec<PathBuf> {
env::split_paths(&env::var_os(dylib_path_var()).unwrap_or(OsString::new()))
.collect()
}