compiler/rustc_codegen_cranelift/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::io::{self, Read, Seek};
   6 use std::path::{Path, PathBuf};
   7
   8 use rustc_codegen_ssa::back::archive::{ArchiveBuilder, ArchiveBuilderBuilder};
   9 use rustc_session::Session;
  10
  11 use object::read::archive::ArchiveFile;
  12 use object::{Object, ObjectSymbol, ReadCache};
  13
  14 #[derive(Debug)]
  15 enum ArchiveEntry {
  16     FromArchive { archive_index: usize, file_range: (u64, u64) },
  17     File(PathBuf),
  18 }
  19
  20 pub(crate) struct ArArchiveBuilderBuilder;
  21
  22 impl ArchiveBuilderBuilder for ArArchiveBuilderBuilder {
  23     fn new_archive_builder<'a>(&self, sess: &'a Session) -> Box<dyn ArchiveBuilder<'a> + 'a> {
  24         Box::new(ArArchiveBuilder {
  25             sess,
  26             use_gnu_style_archive: sess.target.archive_format == "gnu",
  27             // FIXME fix builtin ranlib on macOS
  28             no_builtin_ranlib: sess.target.is_like_osx,
  29
  30             src_archives: vec![],
  31             entries: vec![],
  32         })
  33     }
  34
  35     fn create_dll_import_lib(
  36         &self,
  37         _sess: &Session,
  38         _lib_name: &str,
  39         _dll_imports: &[rustc_session::cstore::DllImport],
  40         _tmpdir: &Path,
  41         _is_direct_dependency: bool,
  42     ) -> PathBuf {
  43         bug!("creating dll imports is not supported");
  44     }
  45 }
  46
  47 pub(crate) struct ArArchiveBuilder<'a> {
  48     sess: &'a Session,
  49     use_gnu_style_archive: bool,
  50     no_builtin_ranlib: bool,
  51
  52     src_archives: Vec<File>,
  53     // Don't use `HashMap` here, as the order is important. `rust.metadata.bin` must always be at
  54     // the end of an archive for linkers to not get confused.
  55     entries: Vec<(Vec<u8>, ArchiveEntry)>,
  56 }
  57
  58 impl<'a> ArchiveBuilder<'a> for ArArchiveBuilder<'a> {
  59     fn add_file(&mut self, file: &Path) {
  60         self.entries.push((
  61             file.file_name().unwrap().to_str().unwrap().to_string().into_bytes(),
  62             ArchiveEntry::File(file.to_owned()),
  63         ));
  64     }
  65
  66     fn add_archive(
  67         &mut self,
  68         archive_path: &Path,
  69         mut skip: Box<dyn FnMut(&str) -> bool + 'static>,
  70     ) -> std::io::Result<()> {
  71         let read_cache = ReadCache::new(std::fs::File::open(&archive_path)?);
  72         let archive = ArchiveFile::parse(&read_cache).unwrap();
  73         let archive_index = self.src_archives.len();
  74
  75         for entry in archive.members() {
  76             let entry = entry.map_err(|err| io::Error::new(io::ErrorKind::InvalidData, err))?;
  77             let file_name = String::from_utf8(entry.name().to_vec())
  78                 .map_err(|err| io::Error::new(io::ErrorKind::InvalidData, err))?;
  79             if !skip(&file_name) {
  80                 self.entries.push((
  81                     file_name.into_bytes(),
  82                     ArchiveEntry::FromArchive { archive_index, file_range: entry.file_range() },
  83                 ));
  84             }
  85         }
  86
  87         self.src_archives.push(read_cache.into_inner());
  88         Ok(())
  89     }
  90
  91     fn build(mut self: Box<Self>, output: &Path) -> bool {
  92         enum BuilderKind {
  93             Bsd(ar::Builder<File>),
  94             Gnu(ar::GnuBuilder<File>),
  95         }
  96
  97         let sess = self.sess;
  98
  99         let mut symbol_table = BTreeMap::new();
 100
 101         let mut entries = Vec::new();
 102
 103         for (mut entry_name, entry) in self.entries {
 104             // FIXME only read the symbol table of the object files to avoid having to keep all
 105             // object files in memory at once, or read them twice.
 106             let data = match entry {
 107                 ArchiveEntry::FromArchive { archive_index, file_range } => {
 108                     // FIXME read symbols from symtab
 109                     let src_read_cache = &mut self.src_archives[archive_index];
 110
 111                     src_read_cache.seek(io::SeekFrom::Start(file_range.0)).unwrap();
 112                     let mut data = std::vec::from_elem(0, usize::try_from(file_range.1).unwrap());
 113                     src_read_cache.read_exact(&mut data).unwrap();
 114
 115                     data
 116                 }
 117                 ArchiveEntry::File(file) => std::fs::read(file).unwrap_or_else(|err| {
 118                     sess.fatal(&format!(
 119                         "error while reading object file during archive building: {}",
 120                         err
 121                     ));
 122                 }),
 123             };
 124
 125             if !self.no_builtin_ranlib {
 126                 if symbol_table.contains_key(&entry_name) {
 127                     // The ar crate can't handle creating a symbol table in case of multiple archive
 128                     // members with the same name. Work around this by prepending a number until we
 129                     // get a unique name.
 130                     for i in 1.. {
 131                         let new_name = format!("{}_", i)
 132                             .into_bytes()
 133                             .into_iter()
 134                             .chain(entry_name.iter().copied())
 135                             .collect::<Vec<_>>();
 136                         if !symbol_table.contains_key(&new_name) {
 137                             entry_name = new_name;
 138                             break;
 139                         }
 140                     }
 141                 }
 142
 143                 match object::File::parse(&*data) {
 144                     Ok(object) => {
 145                         symbol_table.insert(
 146                             entry_name.to_vec(),
 147                             object
 148                                 .symbols()
 149                                 .filter_map(|symbol| {
 150                                     if symbol.is_undefined() || symbol.is_local() {
 151                                         None
 152                                     } else {
 153                                         symbol.name().map(|name| name.as_bytes().to_vec()).ok()
 154                                     }
 155                                 })
 156                                 .collect::<Vec<_>>(),
 157                         );
 158                     }
 159                     Err(err) => {
 160                         let err = err.to_string();
 161                         if err == "Unknown file magic" {
 162                             // Not an object file; skip it.
 163                         } else if object::read::archive::ArchiveFile::parse(&*data).is_ok() {
 164                             // Nested archive file; skip it.
 165                         } else {
 166                             sess.fatal(&format!(
 167                                 "error parsing `{}` during archive creation: {}",
 168                                 String::from_utf8_lossy(&entry_name),
 169                                 err
 170                             ));
 171                         }
 172                     }
 173                 }
 174             }
 175
 176             entries.push((entry_name, data));
 177         }
 178
 179         let mut builder = if self.use_gnu_style_archive {
 180             BuilderKind::Gnu(
 181                 ar::GnuBuilder::new(
 182                     File::create(output).unwrap_or_else(|err| {
 183                         sess.fatal(&format!(
 184                             "error opening destination during archive building: {}",
 185                             err
 186                         ));
 187                     }),
 188                     entries.iter().map(|(name, _)| name.clone()).collect(),
 189                     ar::GnuSymbolTableFormat::Size32,
 190                     symbol_table,
 191                 )
 192                 .unwrap(),
 193             )
 194         } else {
 195             BuilderKind::Bsd(
 196                 ar::Builder::new(
 197                     File::create(output).unwrap_or_else(|err| {
 198                         sess.fatal(&format!(
 199                             "error opening destination during archive building: {}",
 200                             err
 201                         ));
 202                     }),
 203                     symbol_table,
 204                 )
 205                 .unwrap(),
 206             )
 207         };
 208
 209         let any_members = !entries.is_empty();
 210
 211         // Add all files
 212         for (entry_name, data) in entries.into_iter() {
 213             let header = ar::Header::new(entry_name, data.len() as u64);
 214             match builder {
 215                 BuilderKind::Bsd(ref mut builder) => builder.append(&header, &mut &*data).unwrap(),
 216                 BuilderKind::Gnu(ref mut builder) => builder.append(&header, &mut &*data).unwrap(),
 217             }
 218         }
 219
 220         // Finalize archive
 221         std::mem::drop(builder);
 222
 223         if self.no_builtin_ranlib {
 224             let ranlib = crate::toolchain::get_toolchain_binary(self.sess, "ranlib");
 225
 226             // Run ranlib to be able to link the archive
 227             let status = std::process::Command::new(ranlib)
 228                 .arg(output)
 229                 .status()
 230                 .expect("Couldn't run ranlib");
 231
 232             if !status.success() {
 233                 self.sess.fatal(&format!("Ranlib exited with code {:?}", status.code()));
 234             }
 235         }
 236
 237         any_members
 238     }
 239 }