rust/src/librustc_back/archive.rs
2014-12-21 23:31:42 -08:00

327 lines
12 KiB
Rust

// Copyright 2013-2014 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.
//! A helper class for dealing with static archives
use std::io::fs::PathExtensions;
use std::io::process::{Command, ProcessOutput};
use std::io::{fs, TempDir};
use std::io;
use std::os;
use std::str;
use syntax::diagnostic::Handler as ErrorHandler;
pub static METADATA_FILENAME: &'static str = "rust.metadata.bin";
pub struct ArchiveConfig<'a> {
pub handler: &'a ErrorHandler,
pub dst: Path,
pub lib_search_paths: Vec<Path>,
pub slib_prefix: String,
pub slib_suffix: String,
pub maybe_ar_prog: Option<String>
}
pub struct Archive<'a> {
handler: &'a ErrorHandler,
dst: Path,
lib_search_paths: Vec<Path>,
slib_prefix: String,
slib_suffix: String,
maybe_ar_prog: Option<String>
}
/// Helper for adding many files to an archive with a single invocation of
/// `ar`.
#[must_use = "must call build() to finish building the archive"]
pub struct ArchiveBuilder<'a> {
archive: Archive<'a>,
work_dir: TempDir,
/// Filename of each member that should be added to the archive.
members: Vec<Path>,
should_update_symbols: bool,
}
fn run_ar(handler: &ErrorHandler, maybe_ar_prog: &Option<String>,
args: &str, cwd: Option<&Path>,
paths: &[&Path]) -> ProcessOutput {
let ar = match *maybe_ar_prog {
Some(ref ar) => ar[],
None => "ar"
};
let mut cmd = Command::new(ar);
cmd.arg(args).args(paths);
debug!("{}", cmd);
match cwd {
Some(p) => {
cmd.cwd(p);
debug!("inside {}", p.display());
}
None => {}
}
match cmd.spawn() {
Ok(prog) => {
let o = prog.wait_with_output().unwrap();
if !o.status.success() {
handler.err(format!("{} failed with: {}",
cmd,
o.status)[]);
handler.note(format!("stdout ---\n{}",
str::from_utf8(o.output
[]).unwrap())
[]);
handler.note(format!("stderr ---\n{}",
str::from_utf8(o.error
[]).unwrap())
[]);
handler.abort_if_errors();
}
o
},
Err(e) => {
handler.err(format!("could not exec `{}`: {}", ar[],
e)[]);
handler.abort_if_errors();
panic!("rustc::back::archive::run_ar() should not reach this point");
}
}
}
pub fn find_library(name: &str, osprefix: &str, ossuffix: &str,
search_paths: &[Path], handler: &ErrorHandler) -> Path {
// On Windows, static libraries sometimes show up as libfoo.a and other
// times show up as foo.lib
let oslibname = format!("{}{}{}", osprefix, name, ossuffix);
let unixlibname = format!("lib{}.a", name);
for path in search_paths.iter() {
debug!("looking for {} inside {}", name, path.display());
let test = path.join(oslibname[]);
if test.exists() { return test }
if oslibname != unixlibname {
let test = path.join(unixlibname[]);
if test.exists() { return test }
}
}
handler.fatal(format!("could not find native static library `{}`, \
perhaps an -L flag is missing?",
name)[]);
}
impl<'a> Archive<'a> {
fn new(config: ArchiveConfig<'a>) -> Archive<'a> {
let ArchiveConfig { handler, dst, lib_search_paths, slib_prefix, slib_suffix,
maybe_ar_prog } = config;
Archive {
handler: handler,
dst: dst,
lib_search_paths: lib_search_paths,
slib_prefix: slib_prefix,
slib_suffix: slib_suffix,
maybe_ar_prog: maybe_ar_prog
}
}
/// Opens an existing static archive
pub fn open(config: ArchiveConfig<'a>) -> Archive<'a> {
let archive = Archive::new(config);
assert!(archive.dst.exists());
archive
}
/// Removes a file from this archive
pub fn remove_file(&mut self, file: &str) {
run_ar(self.handler, &self.maybe_ar_prog, "d", None, &[&self.dst, &Path::new(file)]);
}
/// Lists all files in an archive
pub fn files(&self) -> Vec<String> {
let output = run_ar(self.handler, &self.maybe_ar_prog, "t", None, &[&self.dst]);
let output = str::from_utf8(output.output[]).unwrap();
// use lines_any because windows delimits output with `\r\n` instead of
// just `\n`
output.lines_any().map(|s| s.to_string()).collect()
}
/// Creates an `ArchiveBuilder` for adding files to this archive.
pub fn extend(self) -> ArchiveBuilder<'a> {
ArchiveBuilder::new(self)
}
}
impl<'a> ArchiveBuilder<'a> {
fn new(archive: Archive<'a>) -> ArchiveBuilder<'a> {
ArchiveBuilder {
archive: archive,
work_dir: TempDir::new("rsar").unwrap(),
members: vec![],
should_update_symbols: false,
}
}
/// Create a new static archive, ready for adding files.
pub fn create(config: ArchiveConfig<'a>) -> ArchiveBuilder<'a> {
let archive = Archive::new(config);
ArchiveBuilder::new(archive)
}
/// Adds all of the contents of a native library to this archive. This will
/// search in the relevant locations for a library named `name`.
pub fn add_native_library(&mut self, name: &str) -> io::IoResult<()> {
let location = find_library(name,
self.archive.slib_prefix[],
self.archive.slib_suffix[],
self.archive.lib_search_paths[],
self.archive.handler);
self.add_archive(&location, name, |_| false)
}
/// Adds all of the contents of the rlib at the specified path to this
/// archive.
///
/// This ignores adding the bytecode from the rlib, and if LTO is enabled
/// then the object file also isn't added.
pub fn add_rlib(&mut self, rlib: &Path, name: &str,
lto: bool) -> io::IoResult<()> {
// Ignoring obj file starting with the crate name
// as simple comparison is not enough - there
// might be also an extra name suffix
let obj_start = format!("{}", name);
let obj_start = obj_start[];
// Ignoring all bytecode files, no matter of
// name
let bc_ext = ".bytecode.deflate";
self.add_archive(rlib, name[], |fname: &str| {
let skip_obj = lto && fname.starts_with(obj_start)
&& fname.ends_with(".o");
skip_obj || fname.ends_with(bc_ext) || fname == METADATA_FILENAME
})
}
/// Adds an arbitrary file to this archive
pub fn add_file(&mut self, file: &Path) -> io::IoResult<()> {
let filename = Path::new(file.filename().unwrap());
let new_file = self.work_dir.path().join(&filename);
try!(fs::copy(file, &new_file));
self.members.push(filename);
Ok(())
}
/// Indicate that the next call to `build` should updates all symbols in
/// the archive (run 'ar s' over it).
pub fn update_symbols(&mut self) {
self.should_update_symbols = true;
}
/// Combine the provided files, rlibs, and native libraries into a single
/// `Archive`.
pub fn build(self) -> Archive<'a> {
// Get an absolute path to the destination, so `ar` will work even
// though we run it from `self.work_dir`.
let abs_dst = os::getcwd().unwrap().join(&self.archive.dst);
assert!(!abs_dst.is_relative());
let mut args = vec![&abs_dst];
let mut total_len = abs_dst.as_vec().len();
if self.members.is_empty() {
// OSX `ar` does not allow using `r` with no members, but it does
// allow running `ar s file.a` to update symbols only.
if self.should_update_symbols {
run_ar(self.archive.handler, &self.archive.maybe_ar_prog,
"s", Some(self.work_dir.path()), args[]);
}
return self.archive;
}
// Don't allow the total size of `args` to grow beyond 32,000 bytes.
// Windows will raise an error if the argument string is longer than
// 32,768, and we leave a bit of extra space for the program name.
static ARG_LENGTH_LIMIT: uint = 32000;
for member_name in self.members.iter() {
let len = member_name.as_vec().len();
// `len + 1` to account for the space that's inserted before each
// argument. (Windows passes command-line arguments as a single
// string, not an array of strings.)
if total_len + len + 1 > ARG_LENGTH_LIMIT {
// Add the archive members seen so far, without updating the
// symbol table (`S`).
run_ar(self.archive.handler, &self.archive.maybe_ar_prog,
"cruS", Some(self.work_dir.path()), args[]);
args.clear();
args.push(&abs_dst);
total_len = abs_dst.as_vec().len();
}
args.push(member_name);
total_len += len + 1;
}
// Add the remaining archive members, and update the symbol table if
// necessary.
let flags = if self.should_update_symbols { "crus" } else { "cruS" };
run_ar(self.archive.handler, &self.archive.maybe_ar_prog,
flags, Some(self.work_dir.path()), args[]);
self.archive
}
fn add_archive<F>(&mut self, archive: &Path, name: &str, mut skip: F) -> io::IoResult<()> where
F: FnMut(&str) -> bool,
{
let loc = TempDir::new("rsar").unwrap();
// First, extract the contents of the archive to a temporary directory.
// We don't unpack directly into `self.work_dir` due to the possibility
// of filename collisions.
let archive = os::make_absolute(archive).unwrap();
run_ar(self.archive.handler, &self.archive.maybe_ar_prog,
"x", Some(loc.path()), &[&archive]);
// Next, we must rename all of the inputs to "guaranteed unique names".
// We move each file into `self.work_dir` under its new unique name.
// The reason for this renaming is that archives are keyed off the name
// of the files, so if two files have the same name they will override
// one another in the archive (bad).
//
// We skip any files explicitly desired for skipping, and we also skip
// all SYMDEF files as these are just magical placeholders which get
// re-created when we make a new archive anyway.
let files = try!(fs::readdir(loc.path()));
for file in files.iter() {
let filename = file.filename_str().unwrap();
if skip(filename) { continue }
if filename.contains(".SYMDEF") { continue }
let filename = format!("r-{}-{}", name, filename);
// LLDB (as mentioned in back::link) crashes on filenames of exactly
// 16 bytes in length. If we're including an object file with
// exactly 16-bytes of characters, give it some prefix so that it's
// not 16 bytes.
let filename = if filename.len() == 16 {
format!("lldb-fix-{}", filename)
} else {
filename
};
let new_filename = self.work_dir.path().join(filename[]);
try!(fs::rename(file, &new_filename));
self.members.push(Path::new(filename));
}
Ok(())
}
}