src/librustc_trans/back/archive.rs

   1 // Copyright 2013-2014 The Rust Project Developers. See the COPYRIGHT
   2 // file at the top-level directory of this distribution and at
   3 // http://rust-lang.org/COPYRIGHT.
   4 //
   5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
   6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
   7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
   8 // option. This file may not be copied, modified, or distributed
   9 // except according to those terms.
  10
  11 //! A helper class for dealing with static archives
  12
  13 use std::env;
  14 use std::ffi::{CString, CStr, OsString};
  15 use std::fs::{self, File};
  16 use std::io::prelude::*;
  17 use std::io;
  18 use std::mem;
  19 use std::path::{Path, PathBuf};
  20 use std::process::{Command, Output, Stdio};
  21 use std::ptr;
  22 use std::str;
  23
  24 use libc;
  25 use llvm::archive_ro::{ArchiveRO, Child};
  26 use llvm::{self, ArchiveKind};
  27 use rustc::metadata::loader::METADATA_FILENAME;
  28 use rustc::session::Session;
  29 use rustc_back::tempdir::TempDir;
  30
  31 pub struct ArchiveConfig<'a> {
  32     pub sess: &'a Session,
  33     pub dst: PathBuf,
  34     pub src: Option<PathBuf>,
  35     pub lib_search_paths: Vec<PathBuf>,
  36     pub ar_prog: String,
  37     pub command_path: OsString,
  38 }
  39
  40 /// Helper for adding many files to an archive with a single invocation of
  41 /// `ar`.
  42 #[must_use = "must call build() to finish building the archive"]
  43 pub struct ArchiveBuilder<'a> {
  44     config: ArchiveConfig<'a>,
  45     work_dir: TempDir,
  46     removals: Vec<String>,
  47     additions: Vec<Addition>,
  48     should_update_symbols: bool,
  49     src_archive: Option<Option<ArchiveRO>>,
  50 }
  51
  52 enum Addition {
  53     File {
  54         path: PathBuf,
  55         name_in_archive: String,
  56     },
  57     Archive {
  58         archive: ArchiveRO,
  59         archive_name: String,
  60         skip: Box<FnMut(&str) -> bool>,
  61     },
  62 }
  63
  64 enum Action<'a> {
  65     Remove(&'a [String]),
  66     AddObjects(&'a [&'a PathBuf], bool),
  67     UpdateSymbols,
  68 }
  69
  70 pub fn find_library(name: &str, search_paths: &[PathBuf], sess: &Session)
  71                     -> PathBuf {
  72     // On Windows, static libraries sometimes show up as libfoo.a and other
  73     // times show up as foo.lib
  74     let oslibname = format!("{}{}{}",
  75                             sess.target.target.options.staticlib_prefix,
  76                             name,
  77                             sess.target.target.options.staticlib_suffix);
  78     let unixlibname = format!("lib{}.a", name);
  79
  80     for path in search_paths {
  81         debug!("looking for {} inside {:?}", name, path);
  82         let test = path.join(&oslibname[..]);
  83         if test.exists() { return test }
  84         if oslibname != unixlibname {
  85             let test = path.join(&unixlibname[..]);
  86             if test.exists() { return test }
  87         }
  88     }
  89     sess.fatal(&format!("could not find native static library `{}`, \
  90                          perhaps an -L flag is missing?", name));
  91 }
  92
  93 fn is_relevant_child(c: &Child) -> bool {
  94     match c.name() {
  95         Some(name) => !name.contains("SYMDEF"),
  96         None => false,
  97     }
  98 }
  99
 100 impl<'a> ArchiveBuilder<'a> {
 101     /// Create a new static archive, ready for modifying the archive specified
 102     /// by `config`.
 103     pub fn new(config: ArchiveConfig<'a>) -> ArchiveBuilder<'a> {
 104         ArchiveBuilder {
 105             config: config,
 106             work_dir: TempDir::new("rsar").unwrap(),
 107             removals: Vec::new(),
 108             additions: Vec::new(),
 109             should_update_symbols: false,
 110             src_archive: None,
 111         }
 112     }
 113
 114     /// Removes a file from this archive
 115     pub fn remove_file(&mut self, file: &str) {
 116         self.removals.push(file.to_string());
 117     }
 118
 119     /// Lists all files in an archive
 120     pub fn src_files(&mut self) -> Vec<String> {
 121         if self.src_archive().is_none() {
 122             return Vec::new()
 123         }
 124         let archive = self.src_archive.as_ref().unwrap().as_ref().unwrap();
 125         let ret = archive.iter()
 126                          .filter(is_relevant_child)
 127                          .filter_map(|child| child.name())
 128                          .filter(|name| !self.removals.iter().any(|x| x == name))
 129                          .map(|name| name.to_string())
 130                          .collect();
 131         return ret;
 132     }
 133
 134     fn src_archive(&mut self) -> Option<&ArchiveRO> {
 135         if let Some(ref a) = self.src_archive {
 136             return a.as_ref()
 137         }
 138         let src = match self.config.src {
 139             Some(ref src) => src,
 140             None => return None,
 141         };
 142         self.src_archive = Some(ArchiveRO::open(src));
 143         self.src_archive.as_ref().unwrap().as_ref()
 144     }
 145
 146     /// Adds all of the contents of a native library to this archive. This will
 147     /// search in the relevant locations for a library named `name`.
 148     pub fn add_native_library(&mut self, name: &str) -> io::Result<()> {
 149         let location = find_library(name, &self.config.lib_search_paths,
 150                                     self.config.sess);
 151         self.add_archive(&location, name, |_| false)
 152     }
 153
 154     /// Adds all of the contents of the rlib at the specified path to this
 155     /// archive.
 156     ///
 157     /// This ignores adding the bytecode from the rlib, and if LTO is enabled
 158     /// then the object file also isn't added.
 159     pub fn add_rlib(&mut self, rlib: &Path, name: &str, lto: bool)
 160                     -> io::Result<()> {
 161         // Ignoring obj file starting with the crate name
 162         // as simple comparison is not enough - there
 163         // might be also an extra name suffix
 164         let obj_start = format!("{}", name);
 165
 166         // Ignoring all bytecode files, no matter of
 167         // name
 168         let bc_ext = ".bytecode.deflate";
 169
 170         self.add_archive(rlib, &name[..], move |fname: &str| {
 171             let skip_obj = lto && fname.starts_with(&obj_start)
 172                 && fname.ends_with(".o");
 173             skip_obj || fname.ends_with(bc_ext) || fname == METADATA_FILENAME
 174         })
 175     }
 176
 177     fn add_archive<F>(&mut self, archive: &Path, name: &str, skip: F)
 178                       -> io::Result<()>
 179         where F: FnMut(&str) -> bool + 'static
 180     {
 181         let archive = match ArchiveRO::open(archive) {
 182             Some(ar) => ar,
 183             None => return Err(io::Error::new(io::ErrorKind::Other,
 184                                               "failed to open archive")),
 185         };
 186         self.additions.push(Addition::Archive {
 187             archive: archive,
 188             archive_name: name.to_string(),
 189             skip: Box::new(skip),
 190         });
 191         Ok(())
 192     }
 193
 194     /// Adds an arbitrary file to this archive
 195     pub fn add_file(&mut self, file: &Path) {
 196         let name = file.file_name().unwrap().to_str().unwrap();
 197         self.additions.push(Addition::File {
 198             path: file.to_path_buf(),
 199             name_in_archive: name.to_string(),
 200         });
 201     }
 202
 203     /// Indicate that the next call to `build` should updates all symbols in
 204     /// the archive (run 'ar s' over it).
 205     pub fn update_symbols(&mut self) {
 206         self.should_update_symbols = true;
 207     }
 208
 209     /// Combine the provided files, rlibs, and native libraries into a single
 210     /// `Archive`.
 211     pub fn build(&mut self) {
 212         let res = match self.llvm_archive_kind() {
 213             Some(kind) => self.build_with_llvm(kind),
 214             None => self.build_with_ar_cmd(),
 215         };
 216         if let Err(e) = res {
 217             self.config.sess.fatal(&format!("failed to build archive: {}", e));
 218         }
 219     }
 220
 221     pub fn llvm_archive_kind(&self) -> Option<ArchiveKind> {
 222         if unsafe { llvm::LLVMVersionMinor() < 7 } {
 223             return None
 224         }
 225
 226         // Currently LLVM only supports writing archives in the 'gnu' format.
 227         match &self.config.sess.target.target.options.archive_format[..] {
 228             "gnu" => Some(ArchiveKind::K_GNU),
 229             "mips64" => Some(ArchiveKind::K_MIPS64),
 230             "bsd" => Some(ArchiveKind::K_BSD),
 231             "coff" => Some(ArchiveKind::K_COFF),
 232             _ => None,
 233         }
 234     }
 235
 236     pub fn using_llvm(&self) -> bool {
 237         self.llvm_archive_kind().is_some()
 238     }
 239
 240     fn build_with_ar_cmd(&mut self) -> io::Result<()> {
 241         let removals = mem::replace(&mut self.removals, Vec::new());
 242         let additions = mem::replace(&mut self.additions, Vec::new());
 243         let should_update_symbols = mem::replace(&mut self.should_update_symbols,
 244                                                  false);
 245
 246         // Don't use fs::copy because libs may be installed as read-only and we
 247         // want to modify this archive, so we use `io::copy` to not preserve
 248         // permission bits.
 249         if let Some(ref s) = self.config.src {
 250             try!(io::copy(&mut try!(File::open(s)),
 251                           &mut try!(File::create(&self.config.dst))));
 252         }
 253
 254         if removals.len() > 0 {
 255             self.run(None, Action::Remove(&removals));
 256         }
 257
 258         let mut members = Vec::new();
 259         for addition in additions {
 260             match addition {
 261                 Addition::File { path, name_in_archive } => {
 262                     let dst = self.work_dir.path().join(&name_in_archive);
 263                     try!(fs::copy(&path, &dst));
 264                     members.push(PathBuf::from(name_in_archive));
 265                 }
 266                 Addition::Archive { archive, archive_name, mut skip } => {
 267                     try!(self.add_archive_members(&mut members, archive,
 268                                                   &archive_name, &mut *skip));
 269                 }
 270             }
 271         }
 272
 273         // Get an absolute path to the destination, so `ar` will work even
 274         // though we run it from `self.work_dir`.
 275         let mut objects = Vec::new();
 276         let mut total_len = self.config.dst.to_string_lossy().len();
 277
 278         if members.is_empty() {
 279             if should_update_symbols {
 280                 self.run(Some(self.work_dir.path()), Action::UpdateSymbols);
 281             }
 282             return Ok(())
 283         }
 284
 285         // Don't allow the total size of `args` to grow beyond 32,000 bytes.
 286         // Windows will raise an error if the argument string is longer than
 287         // 32,768, and we leave a bit of extra space for the program name.
 288         const ARG_LENGTH_LIMIT: usize = 32_000;
 289
 290         for member_name in &members {
 291             let len = member_name.to_string_lossy().len();
 292
 293             // `len + 1` to account for the space that's inserted before each
 294             // argument.  (Windows passes command-line arguments as a single
 295             // string, not an array of strings.)
 296             if total_len + len + 1 > ARG_LENGTH_LIMIT {
 297                 // Add the archive members seen so far, without updating the
 298                 // symbol table.
 299                 self.run(Some(self.work_dir.path()),
 300                          Action::AddObjects(&objects, false));
 301
 302                 objects.clear();
 303                 total_len = self.config.dst.to_string_lossy().len();
 304             }
 305
 306             objects.push(member_name);
 307             total_len += len + 1;
 308         }
 309
 310         // Add the remaining archive members, and update the symbol table if
 311         // necessary.
 312         self.run(Some(self.work_dir.path()),
 313                          Action::AddObjects(&objects, should_update_symbols));
 314         Ok(())
 315     }
 316
 317     fn add_archive_members(&mut self, members: &mut Vec<PathBuf>,
 318                            archive: ArchiveRO, name: &str,
 319                            skip: &mut FnMut(&str) -> bool) -> io::Result<()> {
 320         // Next, we must rename all of the inputs to "guaranteed unique names".
 321         // We write each file into `self.work_dir` under its new unique name.
 322         // The reason for this renaming is that archives are keyed off the name
 323         // of the files, so if two files have the same name they will override
 324         // one another in the archive (bad).
 325         //
 326         // We skip any files explicitly desired for skipping, and we also skip
 327         // all SYMDEF files as these are just magical placeholders which get
 328         // re-created when we make a new archive anyway.
 329         for file in archive.iter().filter(is_relevant_child) {
 330             let filename = file.name().unwrap();
 331             if skip(filename) { continue }
 332             let filename = Path::new(filename).file_name().unwrap()
 333                                               .to_str().unwrap();
 334
 335             // Archives on unix systems typically do not have slashes in
 336             // filenames as the `ar` utility generally only uses the last
 337             // component of a path for the filename list in the archive. On
 338             // Windows, however, archives assembled with `lib.exe` will preserve
 339             // the full path to the file that was placed in the archive,
 340             // including path separators.
 341             //
 342             // The code below is munging paths so it'll go wrong pretty quickly
 343             // if there's some unexpected slashes in the filename, so here we
 344             // just chop off everything but the filename component. Note that
 345             // this can cause duplicate filenames, but that's also handled below
 346             // as well.
 347             let filename = Path::new(filename).file_name().unwrap()
 348                                               .to_str().unwrap();
 349
 350             // An archive can contain files of the same name multiple times, so
 351             // we need to be sure to not have them overwrite one another when we
 352             // extract them. Consequently we need to find a truly unique file
 353             // name for us!
 354             let mut new_filename = String::new();
 355             for n in 0.. {
 356                 let n = if n == 0 {String::new()} else {format!("-{}", n)};
 357                 new_filename = format!("r{}-{}-{}", n, name, filename);
 358
 359                 // LLDB (as mentioned in back::link) crashes on filenames of
 360                 // exactly
 361                 // 16 bytes in length. If we're including an object file with
 362                 //    exactly 16-bytes of characters, give it some prefix so
 363                 //    that it's not 16 bytes.
 364                 new_filename = if new_filename.len() == 16 {
 365                     format!("lldb-fix-{}", new_filename)
 366                 } else {
 367                     new_filename
 368                 };
 369
 370                 let present = members.iter().filter_map(|p| {
 371                     p.file_name().and_then(|f| f.to_str())
 372                 }).any(|s| s == new_filename);
 373                 if !present {
 374                     break
 375                 }
 376             }
 377             let dst = self.work_dir.path().join(&new_filename);
 378             try!(try!(File::create(&dst)).write_all(file.data()));
 379             members.push(PathBuf::from(new_filename));
 380         }
 381         Ok(())
 382     }
 383
 384     fn run(&self, cwd: Option<&Path>, action: Action) -> Output {
 385         let abs_dst = env::current_dir().unwrap().join(&self.config.dst);
 386         let ar = &self.config.ar_prog;
 387         let mut cmd = Command::new(ar);
 388         cmd.env("PATH", &self.config.command_path);
 389         cmd.stdout(Stdio::piped()).stderr(Stdio::piped());
 390         self.prepare_ar_action(&mut cmd, &abs_dst, action);
 391         info!("{:?}", cmd);
 392
 393         if let Some(p) = cwd {
 394             cmd.current_dir(p);
 395             info!("inside {:?}", p.display());
 396         }
 397
 398         let sess = &self.config.sess;
 399         match cmd.spawn() {
 400             Ok(prog) => {
 401                 let o = prog.wait_with_output().unwrap();
 402                 if !o.status.success() {
 403                     sess.err(&format!("{:?} failed with: {}", cmd, o.status));
 404                     sess.note(&format!("stdout ---\n{}",
 405                                        str::from_utf8(&o.stdout).unwrap()));
 406                     sess.note(&format!("stderr ---\n{}",
 407                                        str::from_utf8(&o.stderr).unwrap()));
 408                     sess.abort_if_errors();
 409                 }
 410                 o
 411             },
 412             Err(e) => {
 413                 sess.fatal(&format!("could not exec `{}`: {}",
 414                                     self.config.ar_prog, e));
 415             }
 416         }
 417     }
 418
 419     fn prepare_ar_action(&self, cmd: &mut Command, dst: &Path, action: Action) {
 420         match action {
 421             Action::Remove(files) => {
 422                 cmd.arg("d").arg(dst).args(files);
 423             }
 424             Action::AddObjects(objs, update_symbols) => {
 425                 cmd.arg(if update_symbols {"crs"} else {"crS"})
 426                    .arg(dst)
 427                    .args(objs);
 428             }
 429             Action::UpdateSymbols => {
 430                 cmd.arg("s").arg(dst);
 431             }
 432         }
 433     }
 434
 435     fn build_with_llvm(&mut self, kind: ArchiveKind) -> io::Result<()> {
 436         let mut archives = Vec::new();
 437         let mut strings = Vec::new();
 438         let mut members = Vec::new();
 439         let removals = mem::replace(&mut self.removals, Vec::new());
 440
 441         unsafe {
 442             if let Some(archive) = self.src_archive() {
 443                 for child in archive.iter() {
 444                     let child_name = match child.name() {
 445                         Some(s) => s,
 446                         None => continue,
 447                     };
 448                     if removals.iter().any(|r| r == child_name) {
 449                         continue
 450                     }
 451
 452                     let name = try!(CString::new(child_name));
 453                     members.push(llvm::LLVMRustArchiveMemberNew(ptr::null(),
 454                                                                 name.as_ptr(),
 455                                                                 child.raw()));
 456                     strings.push(name);
 457                 }
 458             }
 459             for addition in mem::replace(&mut self.additions, Vec::new()) {
 460                 match addition {
 461                     Addition::File { path, name_in_archive } => {
 462                         let path = try!(CString::new(path.to_str().unwrap()));
 463                         let name = try!(CString::new(name_in_archive));
 464                         members.push(llvm::LLVMRustArchiveMemberNew(path.as_ptr(),
 465                                                                     name.as_ptr(),
 466                                                                     ptr::null_mut()));
 467                         strings.push(path);
 468                         strings.push(name);
 469                     }
 470                     Addition::Archive { archive, archive_name: _, mut skip } => {
 471                         for child in archive.iter().filter(is_relevant_child) {
 472                             let child_name = child.name().unwrap();
 473                             if skip(child_name) { continue }
 474
 475                             let name = try!(CString::new(child_name));
 476                             let m = llvm::LLVMRustArchiveMemberNew(ptr::null(),
 477                                                                    name.as_ptr(),
 478                                                                    child.raw());
 479                             members.push(m);
 480                             strings.push(name);
 481                         }
 482                         archives.push(archive);
 483                     }
 484                 }
 485             }
 486
 487             let dst = self.config.dst.to_str().unwrap().as_bytes();
 488             let dst = try!(CString::new(dst));
 489             let r = llvm::LLVMRustWriteArchive(dst.as_ptr(),
 490                                                members.len() as libc::size_t,
 491                                                members.as_ptr(),
 492                                                self.should_update_symbols,
 493                                                kind);
 494             let ret = if r != 0 {
 495                 let err = llvm::LLVMRustGetLastError();
 496                 let msg = if err.is_null() {
 497                     "failed to write archive".to_string()
 498                 } else {
 499                     String::from_utf8_lossy(CStr::from_ptr(err).to_bytes())
 500                             .into_owned()
 501                 };
 502                 Err(io::Error::new(io::ErrorKind::Other, msg))
 503             } else {
 504                 Ok(())
 505             };
 506             for member in members {
 507                 llvm::LLVMRustArchiveMemberFree(member);
 508             }
 509             return ret
 510         }
 511     }
 512 }