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::fs::File;
   5 use std::path::{Path, PathBuf};
   6
   7 use rustc_codegen_ssa::back::archive::{find_library, ArchiveBuilder};
   8 use rustc_codegen_ssa::METADATA_FILENAME;
   9 use rustc_session::Session;
  10
  11 use object::{Object, ObjectSymbol, SymbolKind};
  12
  13 #[derive(Debug)]
  14 enum ArchiveEntry {
  15     FromArchive {
  16         archive_index: usize,
  17         entry_index: usize,
  18     },
  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<(PathBuf, ar::Archive<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 mut archive = ar::Archive::new(File::open(input).unwrap());
  41             let mut entries = Vec::new();
  42
  43             let mut i = 0;
  44             while let Some(entry) = archive.next_entry() {
  45                 let entry = entry.unwrap();
  46                 entries.push((
  47                     String::from_utf8(entry.header().identifier().to_vec()).unwrap(),
  48                     ArchiveEntry::FromArchive {
  49                         archive_index: 0,
  50                         entry_index: i,
  51                     },
  52                 ));
  53                 i += 1;
  54             }
  55
  56             (vec![(input.to_owned(), archive)], entries)
  57         } else {
  58             (vec![], Vec::new())
  59         };
  60
  61         ArArchiveBuilder {
  62             sess,
  63             dst: output.to_path_buf(),
  64             lib_search_paths: archive_search_paths(sess),
  65             use_gnu_style_archive: sess.target.archive_format == "gnu",
  66             // FIXME fix builtin ranlib on macOS
  67             no_builtin_ranlib: sess.target.is_like_osx,
  68
  69             src_archives,
  70             entries,
  71         }
  72     }
  73
  74     fn src_files(&mut self) -> Vec<String> {
  75         self.entries.iter().map(|(name, _)| name.clone()).collect()
  76     }
  77
  78     fn remove_file(&mut self, name: &str) {
  79         let index = self
  80             .entries
  81             .iter()
  82             .position(|(entry_name, _)| entry_name == name)
  83             .expect("Tried to remove file not existing in src archive");
  84         self.entries.remove(index);
  85     }
  86
  87     fn add_file(&mut self, file: &Path) {
  88         self.entries.push((
  89             file.file_name().unwrap().to_str().unwrap().to_string(),
  90             ArchiveEntry::File(file.to_owned()),
  91         ));
  92     }
  93
  94     fn add_native_library(&mut self, name: rustc_span::symbol::Symbol) {
  95         let location = find_library(name, &self.lib_search_paths, self.sess);
  96         self.add_archive(location.clone(), |_| false)
  97             .unwrap_or_else(|e| {
  98                 panic!(
  99                     "failed to add native library {}: {}",
 100                     location.to_string_lossy(),
 101                     e
 102                 );
 103             });
 104     }
 105
 106     fn add_rlib(
 107         &mut self,
 108         rlib: &Path,
 109         name: &str,
 110         lto: bool,
 111         skip_objects: bool,
 112     ) -> std::io::Result<()> {
 113         let obj_start = name.to_owned();
 114
 115         self.add_archive(rlib.to_owned(), move |fname: &str| {
 116             // Ignore metadata files, no matter the name.
 117             if fname == METADATA_FILENAME {
 118                 return true;
 119             }
 120
 121             // Don't include Rust objects if LTO is enabled
 122             if lto && fname.starts_with(&obj_start) && fname.ends_with(".o") {
 123                 return true;
 124             }
 125
 126             // Otherwise if this is *not* a rust object and we're skipping
 127             // objects then skip this file
 128             if skip_objects && (!fname.starts_with(&obj_start) || !fname.ends_with(".o")) {
 129                 return true;
 130             }
 131
 132             // ok, don't skip this
 133             false
 134         })
 135     }
 136
 137     fn update_symbols(&mut self) {}
 138
 139     fn build(mut self) {
 140         enum BuilderKind {
 141             Bsd(ar::Builder<File>),
 142             Gnu(ar::GnuBuilder<File>),
 143         }
 144
 145         let sess = self.sess;
 146
 147         let mut symbol_table = BTreeMap::new();
 148
 149         let mut entries = Vec::new();
 150
 151         for (entry_name, entry) in self.entries {
 152             // FIXME only read the symbol table of the object files to avoid having to keep all
 153             // object files in memory at once, or read them twice.
 154             let data = match entry {
 155                 ArchiveEntry::FromArchive {
 156                     archive_index,
 157                     entry_index,
 158                 } => {
 159                     // FIXME read symbols from symtab
 160                     use std::io::Read;
 161                     let (ref _src_archive_path, ref mut src_archive) =
 162                         self.src_archives[archive_index];
 163                     let mut entry = src_archive.jump_to_entry(entry_index).unwrap();
 164                     let mut data = Vec::new();
 165                     entry.read_to_end(&mut data).unwrap();
 166                     data
 167                 }
 168                 ArchiveEntry::File(file) => std::fs::read(file).unwrap_or_else(|err| {
 169                     sess.fatal(&format!(
 170                         "error while reading object file during archive building: {}",
 171                         err
 172                     ));
 173                 }),
 174             };
 175
 176             if !self.no_builtin_ranlib {
 177                 match object::File::parse(&data) {
 178                     Ok(object) => {
 179                         symbol_table.insert(
 180                             entry_name.as_bytes().to_vec(),
 181                             object
 182                                 .symbols()
 183                                 .filter_map(|symbol| {
 184                                     if symbol.is_undefined()
 185                                         || symbol.is_local()
 186                                         || symbol.kind() != SymbolKind::Data
 187                                             && symbol.kind() != SymbolKind::Text
 188                                             && symbol.kind() != SymbolKind::Tls
 189                                     {
 190                                         None
 191                                     } else {
 192                                         symbol.name().map(|name| name.as_bytes().to_vec()).ok()
 193                                     }
 194                                 })
 195                                 .collect::<Vec<_>>(),
 196                         );
 197                     }
 198                     Err(err) => {
 199                         let err = err.to_string();
 200                         if err == "Unknown file magic" {
 201                             // Not an object file; skip it.
 202                         } else {
 203                             sess.fatal(&format!(
 204                                 "error parsing `{}` during archive creation: {}",
 205                                 entry_name, err
 206                             ));
 207                         }
 208                     }
 209                 }
 210             }
 211
 212             entries.push((entry_name, data));
 213         }
 214
 215         let mut builder = if self.use_gnu_style_archive {
 216             BuilderKind::Gnu(
 217                 ar::GnuBuilder::new(
 218                     File::create(&self.dst).unwrap_or_else(|err| {
 219                         sess.fatal(&format!(
 220                             "error opening destination during archive building: {}",
 221                             err
 222                         ));
 223                     }),
 224                     entries
 225                         .iter()
 226                         .map(|(name, _)| name.as_bytes().to_vec())
 227                         .collect(),
 228                     ar::GnuSymbolTableFormat::Size32,
 229                     symbol_table,
 230                 )
 231                 .unwrap(),
 232             )
 233         } else {
 234             BuilderKind::Bsd(
 235                 ar::Builder::new(
 236                     File::create(&self.dst).unwrap_or_else(|err| {
 237                         sess.fatal(&format!(
 238                             "error opening destination during archive building: {}",
 239                             err
 240                         ));
 241                     }),
 242                     symbol_table,
 243                 )
 244                 .unwrap(),
 245             )
 246         };
 247
 248         // Add all files
 249         for (entry_name, data) in entries.into_iter() {
 250             let header = ar::Header::new(entry_name.into_bytes(), data.len() as u64);
 251             match builder {
 252                 BuilderKind::Bsd(ref mut builder) => builder.append(&header, &mut &*data).unwrap(),
 253                 BuilderKind::Gnu(ref mut builder) => builder.append(&header, &mut &*data).unwrap(),
 254             }
 255         }
 256
 257         // Finalize archive
 258         std::mem::drop(builder);
 259
 260         if self.no_builtin_ranlib {
 261             let ranlib = crate::toolchain::get_toolchain_binary(self.sess, "ranlib");
 262
 263             // Run ranlib to be able to link the archive
 264             let status = std::process::Command::new(ranlib)
 265                 .arg(self.dst)
 266                 .status()
 267                 .expect("Couldn't run ranlib");
 268
 269             if !status.success() {
 270                 self.sess
 271                     .fatal(&format!("Ranlib exited with code {:?}", status.code()));
 272             }
 273         }
 274     }
 275 }
 276
 277 impl<'a> ArArchiveBuilder<'a> {
 278     fn add_archive<F>(&mut self, archive_path: PathBuf, mut skip: F) -> std::io::Result<()>
 279     where
 280         F: FnMut(&str) -> bool + 'static,
 281     {
 282         let mut archive = ar::Archive::new(std::fs::File::open(&archive_path)?);
 283         let archive_index = self.src_archives.len();
 284
 285         let mut i = 0;
 286         while let Some(entry) = archive.next_entry() {
 287             let entry = entry?;
 288             let file_name = String::from_utf8(entry.header().identifier().to_vec())
 289                 .map_err(|err| std::io::Error::new(std::io::ErrorKind::InvalidData, err))?;
 290             if !skip(&file_name) {
 291                 self.entries.push((
 292                     file_name,
 293                     ArchiveEntry::FromArchive {
 294                         archive_index,
 295                         entry_index: i,
 296                     },
 297                 ));
 298             }
 299             i += 1;
 300         }
 301
 302         self.src_archives.push((archive_path, archive));
 303         Ok(())
 304     }
 305 }