src/archive.rs

   1 //! Creation of ar archives like for the lib and staticlib crate type
   2
   3 use std::collections::BTreeMap;
   4 use std::convert::TryFrom;
   5 use std::fs::File;
   6 use std::io::{self, Read, Seek};
   7 use std::path::{Path, PathBuf};
   8
   9 use rustc_codegen_ssa::back::archive::{find_library, ArchiveBuilder};
  10 use rustc_codegen_ssa::METADATA_FILENAME;
  11 use rustc_session::Session;
  12
  13 use object::read::archive::ArchiveFile;
  14 use object::{Object, ObjectSymbol, ReadCache, SymbolKind};
  15
  16 #[derive(Debug)]
  17 enum ArchiveEntry {
  18     FromArchive { archive_index: usize, file_range: (u64, u64) },
  19     File(PathBuf),
  20 }
  21
  22 pub(crate) struct ArArchiveBuilder<'a> {
  23     sess: &'a Session,
  24     dst: PathBuf,
  25     lib_search_paths: Vec<PathBuf>,
  26     use_gnu_style_archive: bool,
  27     no_builtin_ranlib: bool,
  28
  29     src_archives: Vec<File>,
  30     // Don't use `HashMap` here, as the order is important. `rust.metadata.bin` must always be at
  31     // the end of an archive for linkers to not get confused.
  32     entries: Vec<(Vec<u8>, ArchiveEntry)>,
  33 }
  34
  35 impl<'a> ArchiveBuilder<'a> for ArArchiveBuilder<'a> {
  36     fn new(sess: &'a Session, output: &Path, input: Option<&Path>) -> Self {
  37         use rustc_codegen_ssa::back::link::archive_search_paths;
  38
  39         let (src_archives, entries) = if let Some(input) = input {
  40             let read_cache = ReadCache::new(File::open(input).unwrap());
  41             let archive = ArchiveFile::parse(&read_cache).unwrap();
  42             let mut entries = Vec::new();
  43
  44             for entry in archive.members() {
  45                 let entry = entry.unwrap();
  46                 entries.push((
  47                     entry.name().to_vec(),
  48                     ArchiveEntry::FromArchive { archive_index: 0, file_range: entry.file_range() },
  49                 ));
  50             }
  51
  52             (vec![read_cache.into_inner()], entries)
  53         } else {
  54             (vec![], Vec::new())
  55         };
  56
  57         ArArchiveBuilder {
  58             sess,
  59             dst: output.to_path_buf(),
  60             lib_search_paths: archive_search_paths(sess),
  61             use_gnu_style_archive: sess.target.archive_format == "gnu",
  62             // FIXME fix builtin ranlib on macOS
  63             no_builtin_ranlib: sess.target.is_like_osx,
  64
  65             src_archives,
  66             entries,
  67         }
  68     }
  69
  70     fn src_files(&mut self) -> Vec<String> {
  71         self.entries.iter().map(|(name, _)| String::from_utf8(name.clone()).unwrap()).collect()
  72     }
  73
  74     fn remove_file(&mut self, name: &str) {
  75         let index = self
  76             .entries
  77             .iter()
  78             .position(|(entry_name, _)| entry_name == name.as_bytes())
  79             .expect("Tried to remove file not existing in src archive");
  80         self.entries.remove(index);
  81     }
  82
  83     fn add_file(&mut self, file: &Path) {
  84         self.entries.push((
  85             file.file_name().unwrap().to_str().unwrap().to_string().into_bytes(),
  86             ArchiveEntry::File(file.to_owned()),
  87         ));
  88     }
  89
  90     fn add_native_library(&mut self, name: rustc_span::symbol::Symbol, verbatim: bool) {
  91         let location = find_library(name, verbatim, &self.lib_search_paths, self.sess);
  92         self.add_archive(location.clone(), |_| false).unwrap_or_else(|e| {
  93             panic!("failed to add native library {}: {}", location.to_string_lossy(), e);
  94         });
  95     }
  96
  97     fn add_rlib(
  98         &mut self,
  99         rlib: &Path,
 100         name: &str,
 101         lto: bool,
 102         skip_objects: bool,
 103     ) -> io::Result<()> {
 104         self.add_archive(rlib.to_owned(), move |fname: &str| {
 105             // Ignore metadata files, no matter the name.
 106             if fname == METADATA_FILENAME {
 107                 return true;
 108             }
 109
 110             // Don't include Rust objects if LTO is enabled
 111             if lto && fname.starts_with(name) && fname.ends_with(".o") {
 112                 return true;
 113             }
 114
 115             // Otherwise if this is *not* a rust object and we're skipping
 116             // objects then skip this file
 117             if skip_objects && (!fname.starts_with(name) || !fname.ends_with(".o")) {
 118                 return true;
 119             }
 120
 121             // ok, don't skip this
 122             false
 123         })
 124     }
 125
 126     fn update_symbols(&mut self) {}
 127
 128     fn build(mut self) {
 129         enum BuilderKind {
 130             Bsd(ar::Builder<File>),
 131             Gnu(ar::GnuBuilder<File>),
 132         }
 133
 134         let sess = self.sess;
 135
 136         let mut symbol_table = BTreeMap::new();
 137
 138         let mut entries = Vec::new();
 139
 140         for (entry_name, entry) in self.entries {
 141             // FIXME only read the symbol table of the object files to avoid having to keep all
 142             // object files in memory at once, or read them twice.
 143             let data = match entry {
 144                 ArchiveEntry::FromArchive { archive_index, file_range } => {
 145                     // FIXME read symbols from symtab
 146                     let src_read_cache = &mut self.src_archives[archive_index];
 147
 148                     src_read_cache.seek(io::SeekFrom::Start(file_range.0)).unwrap();
 149                     let mut data = std::vec::from_elem(0, usize::try_from(file_range.1).unwrap());
 150                     src_read_cache.read_exact(&mut data).unwrap();
 151
 152                     data
 153                 }
 154                 ArchiveEntry::File(file) => std::fs::read(file).unwrap_or_else(|err| {
 155                     sess.fatal(&format!(
 156                         "error while reading object file during archive building: {}",
 157                         err
 158                     ));
 159                 }),
 160             };
 161
 162             if !self.no_builtin_ranlib {
 163                 match object::File::parse(&*data) {
 164                     Ok(object) => {
 165                         symbol_table.insert(
 166                             entry_name.to_vec(),
 167                             object
 168                                 .symbols()
 169                                 .filter_map(|symbol| {
 170                                     if symbol.is_undefined()
 171                                         || symbol.is_local()
 172                                         || symbol.kind() != SymbolKind::Data
 173                                             && symbol.kind() != SymbolKind::Text
 174                                             && symbol.kind() != SymbolKind::Tls
 175                                     {
 176                                         None
 177                                     } else {
 178                                         symbol.name().map(|name| name.as_bytes().to_vec()).ok()
 179                                     }
 180                                 })
 181                                 .collect::<Vec<_>>(),
 182                         );
 183                     }
 184                     Err(err) => {
 185                         let err = err.to_string();
 186                         if err == "Unknown file magic" {
 187                             // Not an object file; skip it.
 188                         } else {
 189                             sess.fatal(&format!(
 190                                 "error parsing `{}` during archive creation: {}",
 191                                 String::from_utf8_lossy(&entry_name),
 192                                 err
 193                             ));
 194                         }
 195                     }
 196                 }
 197             }
 198
 199             entries.push((entry_name, data));
 200         }
 201
 202         let mut builder = if self.use_gnu_style_archive {
 203             BuilderKind::Gnu(
 204                 ar::GnuBuilder::new(
 205                     File::create(&self.dst).unwrap_or_else(|err| {
 206                         sess.fatal(&format!(
 207                             "error opening destination during archive building: {}",
 208                             err
 209                         ));
 210                     }),
 211                     entries.iter().map(|(name, _)| name.clone()).collect(),
 212                     ar::GnuSymbolTableFormat::Size32,
 213                     symbol_table,
 214                 )
 215                 .unwrap(),
 216             )
 217         } else {
 218             BuilderKind::Bsd(
 219                 ar::Builder::new(
 220                     File::create(&self.dst).unwrap_or_else(|err| {
 221                         sess.fatal(&format!(
 222                             "error opening destination during archive building: {}",
 223                             err
 224                         ));
 225                     }),
 226                     symbol_table,
 227                 )
 228                 .unwrap(),
 229             )
 230         };
 231
 232         // Add all files
 233         for (entry_name, data) in entries.into_iter() {
 234             let header = ar::Header::new(entry_name, data.len() as u64);
 235             match builder {
 236                 BuilderKind::Bsd(ref mut builder) => builder.append(&header, &mut &*data).unwrap(),
 237                 BuilderKind::Gnu(ref mut builder) => builder.append(&header, &mut &*data).unwrap(),
 238             }
 239         }
 240
 241         // Finalize archive
 242         std::mem::drop(builder);
 243
 244         if self.no_builtin_ranlib {
 245             let ranlib = crate::toolchain::get_toolchain_binary(self.sess, "ranlib");
 246
 247             // Run ranlib to be able to link the archive
 248             let status = std::process::Command::new(ranlib)
 249                 .arg(self.dst)
 250                 .status()
 251                 .expect("Couldn't run ranlib");
 252
 253             if !status.success() {
 254                 self.sess.fatal(&format!("Ranlib exited with code {:?}", status.code()));
 255             }
 256         }
 257     }
 258
 259     fn inject_dll_import_lib(
 260         &mut self,
 261         _lib_name: &str,
 262         _dll_imports: &[rustc_middle::middle::cstore::DllImport],
 263         _tmpdir: &rustc_data_structures::temp_dir::MaybeTempDir,
 264     ) {
 265         bug!("injecting dll imports is not supported");
 266     }
 267 }
 268
 269 impl<'a> ArArchiveBuilder<'a> {
 270     fn add_archive<F>(&mut self, archive_path: PathBuf, mut skip: F) -> io::Result<()>
 271     where
 272         F: FnMut(&str) -> bool,
 273     {
 274         let read_cache = ReadCache::new(std::fs::File::open(&archive_path)?);
 275         let archive = ArchiveFile::parse(&read_cache).unwrap();
 276         let archive_index = self.src_archives.len();
 277
 278         for entry in archive.members() {
 279             let entry = entry.map_err(|err| io::Error::new(io::ErrorKind::InvalidData, err))?;
 280             let file_name = String::from_utf8(entry.name().to_vec())
 281                 .map_err(|err| io::Error::new(io::ErrorKind::InvalidData, err))?;
 282             if !skip(&file_name) {
 283                 self.entries.push((
 284                     file_name.into_bytes(),
 285                     ArchiveEntry::FromArchive { archive_index, file_range: entry.file_range() },
 286                 ));
 287             }
 288         }
 289
 290         self.src_archives.push(read_cache.into_inner());
 291         Ok(())
 292     }
 293 }