rust/src/librustc_back/archive.rs
Steve Klabnik 7828c3dd28 Rename fail! to panic!
https://github.com/rust-lang/rfcs/pull/221

The current terminology of "task failure" often causes problems when
writing or speaking about code. You often want to talk about the
possibility of an operation that returns a Result "failing", but cannot
because of the ambiguity with task failure. Instead, you have to speak
of "the failing case" or "when the operation does not succeed" or other
circumlocutions.

Likewise, we use a "Failure" header in rustdoc to describe when
operations may fail the task, but it would often be helpful to separate
out a section describing the "Err-producing" case.

We have been steadily moving away from task failure and toward Result as
an error-handling mechanism, so we should optimize our terminology
accordingly: Result-producing functions should be easy to describe.

To update your code, rename any call to `fail!` to `panic!` instead.
Assuming you have not created your own macro named `panic!`, this
will work on UNIX based systems:

    grep -lZR 'fail!' . | xargs -0 -l sed -i -e 's/fail!/panic!/g'

You can of course also do this by hand.

[breaking-change]
2014-10-29 11:43:07 -04:00

317 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::abi;
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 os: abi::Os,
pub maybe_ar_prog: Option<String>
}
pub struct Archive<'a> {
handler: &'a ErrorHandler,
dst: Path,
lib_search_paths: Vec<Path>,
os: abi::Os,
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.as_slice(),
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).as_slice());
handler.note(format!("stdout ---\n{}",
str::from_utf8(o.output
.as_slice()).unwrap())
.as_slice());
handler.note(format!("stderr ---\n{}",
str::from_utf8(o.error
.as_slice()).unwrap())
.as_slice());
handler.abort_if_errors();
}
o
},
Err(e) => {
handler.err(format!("could not exec `{}`: {}", ar.as_slice(),
e).as_slice());
handler.abort_if_errors();
panic!("rustc::back::archive::run_ar() should not reach this point");
}
}
}
pub fn find_library(name: &str, os: abi::Os, search_paths: &[Path],
handler: &ErrorHandler) -> Path {
let (osprefix, osext) = match os {
abi::OsWindows => ("", "lib"), _ => ("lib", "a"),
};
// On Windows, static libraries sometimes show up as libfoo.a and other
// times show up as foo.lib
let oslibname = format!("{}{}.{}", osprefix, name, osext);
let unixlibname = format!("lib{}.a", name);
for path in search_paths.iter() {
debug!("looking for {} inside {}", name, path.display());
let test = path.join(oslibname.as_slice());
if test.exists() { return test }
if oslibname != unixlibname {
let test = path.join(unixlibname.as_slice());
if test.exists() { return test }
}
}
handler.fatal(format!("could not find native static library `{}`, \
perhaps an -L flag is missing?",
name).as_slice());
}
impl<'a> Archive<'a> {
fn new(config: ArchiveConfig<'a>) -> Archive<'a> {
let ArchiveConfig { handler, dst, lib_search_paths, os, maybe_ar_prog } = config;
Archive {
handler: handler,
dst: dst,
lib_search_paths: lib_search_paths,
os: os,
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.as_slice()).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.os,
self.archive.lib_search_paths.as_slice(),
self.archive.handler);
self.add_archive(&location, name, [])
}
/// 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<()> {
let object = format!("{}.o", name);
let bytecode = format!("{}.bytecode.deflate", name);
let mut ignore = vec!(bytecode.as_slice(), METADATA_FILENAME);
if lto {
ignore.push(object.as_slice());
}
self.add_archive(rlib, name, ignore.as_slice())
}
/// 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().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.as_slice());
}
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.as_slice());
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.as_slice());
self.archive
}
fn add_archive(&mut self, archive: &Path, name: &str,
skip: &[&str]) -> io::IoResult<()> {
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);
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.iter().any(|s| *s == 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.as_slice());
try!(fs::rename(file, &new_filename));
self.members.push(Path::new(filename));
}
Ok(())
}
}