rust/compiler/rustc_session/src/filesearch.rs

125 lines
4.3 KiB
Rust

//! A module for searching for libraries
use std::env;
use std::fs;
use std::iter::FromIterator;
use std::path::{Path, PathBuf};
use crate::search_paths::{PathKind, SearchPath};
use rustc_fs_util::fix_windows_verbatim_for_gcc;
#[derive(Copy, Clone)]
pub enum FileMatch {
FileMatches,
FileDoesntMatch,
}
#[derive(Clone)]
pub struct FileSearch<'a> {
sysroot: &'a Path,
triple: &'a str,
search_paths: &'a [SearchPath],
tlib_path: &'a SearchPath,
kind: PathKind,
}
impl<'a> FileSearch<'a> {
pub fn search_paths(&self) -> impl Iterator<Item = &'a SearchPath> {
let kind = self.kind;
self.search_paths
.iter()
.filter(move |sp| sp.kind.matches(kind))
.chain(std::iter::once(self.tlib_path))
}
pub fn get_lib_path(&self) -> PathBuf {
make_target_lib_path(self.sysroot, self.triple)
}
pub fn get_self_contained_lib_path(&self) -> PathBuf {
self.get_lib_path().join("self-contained")
}
pub fn new(
sysroot: &'a Path,
triple: &'a str,
search_paths: &'a [SearchPath],
tlib_path: &'a SearchPath,
kind: PathKind,
) -> FileSearch<'a> {
debug!("using sysroot = {}, triple = {}", sysroot.display(), triple);
FileSearch { sysroot, triple, search_paths, tlib_path, kind }
}
/// Returns just the directories within the search paths.
pub fn search_path_dirs(&self) -> Vec<PathBuf> {
self.search_paths().map(|sp| sp.dir.to_path_buf()).collect()
}
}
pub fn make_target_lib_path(sysroot: &Path, target_triple: &str) -> PathBuf {
let rustlib_path = rustc_target::target_rustlib_path(sysroot, target_triple);
PathBuf::from_iter([sysroot, Path::new(&rustlib_path), Path::new("lib")])
}
/// This function checks if sysroot is found using env::args().next(), and if it
/// is not found, uses env::current_exe() to imply sysroot.
pub fn get_or_default_sysroot() -> PathBuf {
// Follow symlinks. If the resolved path is relative, make it absolute.
fn canonicalize(path: PathBuf) -> PathBuf {
let path = fs::canonicalize(&path).unwrap_or(path);
// See comments on this target function, but the gist is that
// gcc chokes on verbatim paths which fs::canonicalize generates
// so we try to avoid those kinds of paths.
fix_windows_verbatim_for_gcc(&path)
}
// Use env::current_exe() to get the path of the executable following
// symlinks/canonicalizing components.
fn from_current_exe() -> PathBuf {
match env::current_exe() {
Ok(exe) => {
let mut p = canonicalize(exe);
p.pop();
p.pop();
p
}
Err(e) => panic!("failed to get current_exe: {e}"),
}
}
// Use env::args().next() to get the path of the executable without
// following symlinks/canonicalizing any component. This makes the rustc
// binary able to locate Rust libraries in systems using content-addressable
// storage (CAS).
fn from_env_args_next() -> Option<PathBuf> {
match env::args_os().next() {
Some(first_arg) => {
let mut p = PathBuf::from(first_arg);
// Check if sysroot is found using env::args().next() only if the rustc in argv[0]
// is a symlink (see #79253). We might want to change/remove it to conform with
// https://www.gnu.org/prep/standards/standards.html#Finding-Program-Files in the
// future.
if fs::read_link(&p).is_err() {
// Path is not a symbolic link or does not exist.
return None;
}
// Pop off `bin/rustc`, obtaining the suspected sysroot.
p.pop();
p.pop();
// Look for the target rustlib directory in the suspected sysroot.
let mut rustlib_path = rustc_target::target_rustlib_path(&p, "dummy");
rustlib_path.pop(); // pop off the dummy target.
if rustlib_path.exists() { Some(p) } else { None }
}
None => None,
}
}
// Check if sysroot is found using env::args().next(), and if is not found,
// use env::current_exe() to imply sysroot.
from_env_args_next().unwrap_or_else(from_current_exe)
}