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<(String, 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                     String::from_utf8(entry.name().to_vec()).unwrap(),
  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, _)| name.clone()).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)
  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(),
  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         let obj_start = name.to_owned();
 105
 106         self.add_archive(rlib.to_owned(), move |fname: &str| {
 107             // Ignore metadata files, no matter the name.
 108             if fname == METADATA_FILENAME {
 109                 return true;
 110             }
 111
 112             // Don't include Rust objects if LTO is enabled
 113             if lto && fname.starts_with(&obj_start) && fname.ends_with(".o") {
 114                 return true;
 115             }
 116
 117             // Otherwise if this is *not* a rust object and we're skipping
 118             // objects then skip this file
 119             if skip_objects && (!fname.starts_with(&obj_start) || !fname.ends_with(".o")) {
 120                 return true;
 121             }
 122
 123             // ok, don't skip this
 124             false
 125         })
 126     }
 127
 128     fn update_symbols(&mut self) {}
 129
 130     fn build(mut self) {
 131         enum BuilderKind {
 132             Bsd(ar::Builder<File>),
 133             Gnu(ar::GnuBuilder<File>),
 134         }
 135
 136         let sess = self.sess;
 137
 138         let mut symbol_table = BTreeMap::new();
 139
 140         let mut entries = Vec::new();
 141
 142         for (entry_name, entry) in self.entries {
 143             // FIXME only read the symbol table of the object files to avoid having to keep all
 144             // object files in memory at once, or read them twice.
 145             let data = match entry {
 146                 ArchiveEntry::FromArchive { archive_index, file_range } => {
 147                     // FIXME read symbols from symtab
 148                     let src_read_cache = &mut self.src_archives[archive_index];
 149
 150                     src_read_cache.seek(io::SeekFrom::Start(file_range.0)).unwrap();
 151                     let mut data = std::vec::from_elem(0, usize::try_from(file_range.1).unwrap());
 152                     src_read_cache.read_exact(&mut data).unwrap();
 153
 154                     data
 155                 }
 156                 ArchiveEntry::File(file) => std::fs::read(file).unwrap_or_else(|err| {
 157                     sess.fatal(&format!(
 158                         "error while reading object file during archive building: {}",
 159                         err
 160                     ));
 161                 }),
 162             };
 163
 164             if !self.no_builtin_ranlib {
 165                 match object::File::parse(&*data) {
 166                     Ok(object) => {
 167                         symbol_table.insert(
 168                             entry_name.as_bytes().to_vec(),
 169                             object
 170                                 .symbols()
 171                                 .filter_map(|symbol| {
 172                                     if symbol.is_undefined()
 173                                         || symbol.is_local()
 174                                         || symbol.kind() != SymbolKind::Data
 175                                             && symbol.kind() != SymbolKind::Text
 176                                             && symbol.kind() != SymbolKind::Tls
 177                                     {
 178                                         None
 179                                     } else {
 180                                         symbol.name().map(|name| name.as_bytes().to_vec()).ok()
 181                                     }
 182                                 })
 183                                 .collect::<Vec<_>>(),
 184                         );
 185                     }
 186                     Err(err) => {
 187                         let err = err.to_string();
 188                         if err == "Unknown file magic" {
 189                             // Not an object file; skip it.
 190                         } else {
 191                             sess.fatal(&format!(
 192                                 "error parsing `{}` during archive creation: {}",
 193                                 entry_name, err
 194                             ));
 195                         }
 196                     }
 197                 }
 198             }
 199
 200             entries.push((entry_name, data));
 201         }
 202
 203         let mut builder = if self.use_gnu_style_archive {
 204             BuilderKind::Gnu(
 205                 ar::GnuBuilder::new(
 206                     File::create(&self.dst).unwrap_or_else(|err| {
 207                         sess.fatal(&format!(
 208                             "error opening destination during archive building: {}",
 209                             err
 210                         ));
 211                     }),
 212                     entries.iter().map(|(name, _)| name.as_bytes().to_vec()).collect(),
 213                     ar::GnuSymbolTableFormat::Size32,
 214                     symbol_table,
 215                 )
 216                 .unwrap(),
 217             )
 218         } else {
 219             BuilderKind::Bsd(
 220                 ar::Builder::new(
 221                     File::create(&self.dst).unwrap_or_else(|err| {
 222                         sess.fatal(&format!(
 223                             "error opening destination during archive building: {}",
 224                             err
 225                         ));
 226                     }),
 227                     symbol_table,
 228                 )
 229                 .unwrap(),
 230             )
 231         };
 232
 233         // Add all files
 234         for (entry_name, data) in entries.into_iter() {
 235             let header = ar::Header::new(entry_name.into_bytes(), data.len() as u64);
 236             match builder {
 237                 BuilderKind::Bsd(ref mut builder) => builder.append(&header, &mut &*data).unwrap(),
 238                 BuilderKind::Gnu(ref mut builder) => builder.append(&header, &mut &*data).unwrap(),
 239             }
 240         }
 241
 242         // Finalize archive
 243         std::mem::drop(builder);
 244
 245         if self.no_builtin_ranlib {
 246             let ranlib = crate::toolchain::get_toolchain_binary(self.sess, "ranlib");
 247
 248             // Run ranlib to be able to link the archive
 249             let status = std::process::Command::new(ranlib)
 250                 .arg(self.dst)
 251                 .status()
 252                 .expect("Couldn't run ranlib");
 253
 254             if !status.success() {
 255                 self.sess.fatal(&format!("Ranlib exited with code {:?}", status.code()));
 256             }
 257         }
 258     }
 259
 260     fn inject_dll_import_lib(
 261         &mut self,
 262         _lib_name: &str,
 263         _dll_imports: &[rustc_middle::middle::cstore::DllImport],
 264         _tmpdir: &rustc_data_structures::temp_dir::MaybeTempDir,
 265     ) {
 266         bug!("injecting dll imports is not supported");
 267     }
 268 }
 269
 270 impl<'a> ArArchiveBuilder<'a> {
 271     fn add_archive<F>(&mut self, archive_path: PathBuf, mut skip: F) -> io::Result<()>
 272     where
 273         F: FnMut(&str) -> bool + 'static,
 274     {
 275         let read_cache = ReadCache::new(std::fs::File::open(&archive_path)?);
 276         let archive = ArchiveFile::parse(&read_cache).unwrap();
 277         let archive_index = self.src_archives.len();
 278
 279         for entry in archive.members() {
 280             let entry = entry.map_err(|err| io::Error::new(io::ErrorKind::InvalidData, err))?;
 281             let file_name = String::from_utf8(entry.name().to_vec())
 282                 .map_err(|err| io::Error::new(io::ErrorKind::InvalidData, err))?;
 283             if !skip(&file_name) {
 284                 self.entries.push((
 285                     file_name,
 286                     ArchiveEntry::FromArchive { archive_index, file_range: entry.file_range() },
 287                 ));
 288             }
 289         }
 290
 291         self.src_archives.push(read_cache.into_inner());
 292         Ok(())
 293     }
 294 }