compiler/rustc_codegen_ssa/src/back/archive.rs

   1 use rustc_data_structures::fx::FxHashSet;
   2 use rustc_data_structures::memmap::Mmap;
   3 use rustc_session::cstore::DllImport;
   4 use rustc_session::Session;
   5 use rustc_span::symbol::Symbol;
   6
   7 use super::metadata::search_for_section;
   8
   9 pub use ar_archive_writer::get_native_object_symbols;
  10 use ar_archive_writer::{write_archive_to_stream, ArchiveKind, NewArchiveMember};
  11 use object::read::archive::ArchiveFile;
  12 use object::read::macho::FatArch;
  13 use tempfile::Builder as TempFileBuilder;
  14
  15 use std::error::Error;
  16 use std::fs::File;
  17 use std::io;
  18 use std::path::{Path, PathBuf};
  19
  20 // Re-exporting for rustc_codegen_llvm::back::archive
  21 pub use crate::errors::{ArchiveBuildFailure, ExtractBundledLibsError, UnknownArchiveKind};
  22
  23 pub trait ArchiveBuilderBuilder {
  24     fn new_archive_builder<'a>(&self, sess: &'a Session) -> Box<dyn ArchiveBuilder<'a> + 'a>;
  25
  26     /// Creates a DLL Import Library <https://docs.microsoft.com/en-us/windows/win32/dlls/dynamic-link-library-creation#creating-an-import-library>.
  27     /// and returns the path on disk to that import library.
  28     /// This functions doesn't take `self` so that it can be called from
  29     /// `linker_with_args`, which is specialized on `ArchiveBuilder` but
  30     /// doesn't take or create an instance of that type.
  31     fn create_dll_import_lib(
  32         &self,
  33         sess: &Session,
  34         lib_name: &str,
  35         dll_imports: &[DllImport],
  36         tmpdir: &Path,
  37         is_direct_dependency: bool,
  38     ) -> PathBuf;
  39
  40     fn extract_bundled_libs<'a>(
  41         &'a self,
  42         rlib: &'a Path,
  43         outdir: &Path,
  44         bundled_lib_file_names: &FxHashSet<Symbol>,
  45     ) -> Result<(), ExtractBundledLibsError<'_>> {
  46         let archive_map = unsafe {
  47             Mmap::map(
  48                 File::open(rlib)
  49                     .map_err(|e| ExtractBundledLibsError::OpenFile { rlib, error: Box::new(e) })?,
  50             )
  51             .map_err(|e| ExtractBundledLibsError::MmapFile { rlib, error: Box::new(e) })?
  52         };
  53         let archive = ArchiveFile::parse(&*archive_map)
  54             .map_err(|e| ExtractBundledLibsError::ParseArchive { rlib, error: Box::new(e) })?;
  55
  56         for entry in archive.members() {
  57             let entry = entry
  58                 .map_err(|e| ExtractBundledLibsError::ReadEntry { rlib, error: Box::new(e) })?;
  59             let data = entry
  60                 .data(&*archive_map)
  61                 .map_err(|e| ExtractBundledLibsError::ArchiveMember { rlib, error: Box::new(e) })?;
  62             let name = std::str::from_utf8(entry.name())
  63                 .map_err(|e| ExtractBundledLibsError::ConvertName { rlib, error: Box::new(e) })?;
  64             if !bundled_lib_file_names.contains(&Symbol::intern(name)) {
  65                 continue; // We need to extract only native libraries.
  66             }
  67             let data = search_for_section(rlib, data, ".bundled_lib").map_err(|e| {
  68                 ExtractBundledLibsError::ExtractSection { rlib, error: Box::<dyn Error>::from(e) }
  69             })?;
  70             std::fs::write(&outdir.join(&name), data)
  71                 .map_err(|e| ExtractBundledLibsError::WriteFile { rlib, error: Box::new(e) })?;
  72         }
  73         Ok(())
  74     }
  75 }
  76
  77 pub trait ArchiveBuilder<'a> {
  78     fn add_file(&mut self, path: &Path);
  79
  80     fn add_archive(
  81         &mut self,
  82         archive: &Path,
  83         skip: Box<dyn FnMut(&str) -> bool + 'static>,
  84     ) -> io::Result<()>;
  85
  86     fn build(self: Box<Self>, output: &Path) -> bool;
  87 }
  88
  89 #[must_use = "must call build() to finish building the archive"]
  90 pub struct ArArchiveBuilder<'a> {
  91     sess: &'a Session,
  92     get_object_symbols:
  93         fn(buf: &[u8], f: &mut dyn FnMut(&[u8]) -> io::Result<()>) -> io::Result<bool>,
  94
  95     src_archives: Vec<(PathBuf, Mmap)>,
  96     // Don't use an `HashMap` here, as the order is important. `lib.rmeta` needs
  97     // to be at the end of an archive in some cases for linkers to not get confused.
  98     entries: Vec<(Vec<u8>, ArchiveEntry)>,
  99 }
 100
 101 #[derive(Debug)]
 102 enum ArchiveEntry {
 103     FromArchive { archive_index: usize, file_range: (u64, u64) },
 104     File(PathBuf),
 105 }
 106
 107 impl<'a> ArArchiveBuilder<'a> {
 108     pub fn new(
 109         sess: &'a Session,
 110         get_object_symbols: fn(
 111             buf: &[u8],
 112             f: &mut dyn FnMut(&[u8]) -> io::Result<()>,
 113         ) -> io::Result<bool>,
 114     ) -> ArArchiveBuilder<'a> {
 115         ArArchiveBuilder { sess, get_object_symbols, src_archives: vec![], entries: vec![] }
 116     }
 117 }
 118
 119 fn try_filter_fat_archs<'a>(
 120     archs: object::read::Result<&[impl FatArch]>,
 121     target_arch: object::Architecture,
 122     archive_map_data: &'a [u8],
 123 ) -> io::Result<Option<(&'a [u8], u64)>> {
 124     let archs = archs.map_err(|e| io::Error::new(io::ErrorKind::Other, e))?;
 125
 126     let desired = match archs.iter().find(|a| a.architecture() == target_arch) {
 127         Some(a) => a,
 128         None => return Ok(None),
 129     };
 130
 131     Ok(Some((
 132         desired.data(archive_map_data).map_err(|e| io::Error::new(io::ErrorKind::Other, e))?,
 133         desired.offset().into(),
 134     )))
 135 }
 136
 137 pub fn try_extract_macho_fat_archive<'a>(
 138     sess: &Session,
 139     archive_bytes: &'a [u8],
 140 ) -> io::Result<Option<(&'a [u8], u64)>> {
 141     let target_arch = match sess.target.arch.as_ref() {
 142         "aarch64" => object::Architecture::Aarch64,
 143         "x86_64" => object::Architecture::X86_64,
 144         _ => return Ok(None),
 145     };
 146
 147     match object::macho::FatHeader::parse(archive_bytes) {
 148         Ok(h) if h.magic.get(object::endian::BigEndian) == object::macho::FAT_MAGIC => {
 149             let archs = object::macho::FatHeader::parse_arch32(archive_bytes);
 150             try_filter_fat_archs(archs, target_arch, archive_bytes)
 151         }
 152         Ok(h) if h.magic.get(object::endian::BigEndian) == object::macho::FAT_MAGIC_64 => {
 153             let archs = object::macho::FatHeader::parse_arch64(archive_bytes);
 154             try_filter_fat_archs(archs, target_arch, archive_bytes)
 155         }
 156         // Not a FatHeader at all, just return None.
 157         _ => Ok(None),
 158     }
 159 }
 160
 161 impl<'a> ArchiveBuilder<'a> for ArArchiveBuilder<'a> {
 162     fn add_archive(
 163         &mut self,
 164         archive_path: &Path,
 165         mut skip: Box<dyn FnMut(&str) -> bool + 'static>,
 166     ) -> io::Result<()> {
 167         let archive_map = unsafe { Mmap::map(File::open(&archive_path)?)? };
 168         if self.src_archives.iter().any(|archive| archive.0 == archive_path) {
 169             return Ok(());
 170         }
 171
 172         let (archive_bytes, offset) = if self.sess.target.llvm_target.contains("-apple-macosx") {
 173             if let Some((sub_archive, archive_offset)) =
 174                 try_extract_macho_fat_archive(&self.sess, &*archive_map)?
 175             {
 176                 (sub_archive, Some(archive_offset))
 177             } else {
 178                 (&*archive_map, None)
 179             }
 180         } else {
 181             (&*archive_map, None)
 182         };
 183
 184         let archive = ArchiveFile::parse(&*archive_bytes)
 185             .map_err(|err| io::Error::new(io::ErrorKind::InvalidData, err))?;
 186         let archive_index = self.src_archives.len();
 187
 188         for entry in archive.members() {
 189             let entry = entry.map_err(|err| io::Error::new(io::ErrorKind::InvalidData, err))?;
 190             let file_name = String::from_utf8(entry.name().to_vec())
 191                 .map_err(|err| io::Error::new(io::ErrorKind::InvalidData, err))?;
 192             if !skip(&file_name) {
 193                 let mut range = entry.file_range();
 194                 if let Some(offset) = offset {
 195                     range.0 += offset;
 196                 }
 197                 self.entries.push((
 198                     file_name.into_bytes(),
 199                     ArchiveEntry::FromArchive { archive_index, file_range: range },
 200                 ));
 201             }
 202         }
 203
 204         self.src_archives.push((archive_path.to_owned(), archive_map));
 205         Ok(())
 206     }
 207
 208     /// Adds an arbitrary file to this archive
 209     fn add_file(&mut self, file: &Path) {
 210         self.entries.push((
 211             file.file_name().unwrap().to_str().unwrap().to_string().into_bytes(),
 212             ArchiveEntry::File(file.to_owned()),
 213         ));
 214     }
 215
 216     /// Combine the provided files, rlibs, and native libraries into a single
 217     /// `Archive`.
 218     fn build(self: Box<Self>, output: &Path) -> bool {
 219         let sess = self.sess;
 220         match self.build_inner(output) {
 221             Ok(any_members) => any_members,
 222             Err(e) => sess.emit_fatal(ArchiveBuildFailure { error: e }),
 223         }
 224     }
 225 }
 226
 227 impl<'a> ArArchiveBuilder<'a> {
 228     fn build_inner(self, output: &Path) -> io::Result<bool> {
 229         let archive_kind = match &*self.sess.target.archive_format {
 230             "gnu" => ArchiveKind::Gnu,
 231             "bsd" => ArchiveKind::Bsd,
 232             "darwin" => ArchiveKind::Darwin,
 233             "coff" => ArchiveKind::Coff,
 234             kind => {
 235                 self.sess.emit_fatal(UnknownArchiveKind { kind });
 236             }
 237         };
 238
 239         let mut entries = Vec::new();
 240
 241         for (entry_name, entry) in self.entries {
 242             let data =
 243                 match entry {
 244                     ArchiveEntry::FromArchive { archive_index, file_range } => {
 245                         let src_archive = &self.src_archives[archive_index];
 246
 247                         let data = &src_archive.1
 248                             [file_range.0 as usize..file_range.0 as usize + file_range.1 as usize];
 249
 250                         Box::new(data) as Box<dyn AsRef<[u8]>>
 251                     }
 252                     ArchiveEntry::File(file) => unsafe {
 253                         Box::new(
 254                             Mmap::map(File::open(file).map_err(|err| {
 255                                 io_error_context("failed to open object file", err)
 256                             })?)
 257                             .map_err(|err| io_error_context("failed to map object file", err))?,
 258                         ) as Box<dyn AsRef<[u8]>>
 259                     },
 260                 };
 261
 262             entries.push(NewArchiveMember {
 263                 buf: data,
 264                 get_symbols: self.get_object_symbols,
 265                 member_name: String::from_utf8(entry_name).unwrap(),
 266                 mtime: 0,
 267                 uid: 0,
 268                 gid: 0,
 269                 perms: 0o644,
 270             })
 271         }
 272
 273         // Write to a temporary file first before atomically renaming to the final name.
 274         // This prevents programs (including rustc) from attempting to read a partial archive.
 275         // It also enables writing an archive with the same filename as a dependency on Windows as
 276         // required by a test.
 277         let mut archive_tmpfile = TempFileBuilder::new()
 278             .suffix(".temp-archive")
 279             .tempfile_in(output.parent().unwrap_or_else(|| Path::new("")))
 280             .map_err(|err| io_error_context("couldn't create a temp file", err))?;
 281
 282         write_archive_to_stream(
 283             archive_tmpfile.as_file_mut(),
 284             &entries,
 285             true,
 286             archive_kind,
 287             true,
 288             false,
 289         )?;
 290
 291         let any_entries = !entries.is_empty();
 292         drop(entries);
 293         // Drop src_archives to unmap all input archives, which is necessary if we want to write the
 294         // output archive to the same location as an input archive on Windows.
 295         drop(self.src_archives);
 296
 297         archive_tmpfile
 298             .persist(output)
 299             .map_err(|err| io_error_context("failed to rename archive file", err.error))?;
 300
 301         Ok(any_entries)
 302     }
 303 }
 304
 305 fn io_error_context(context: &str, err: io::Error) -> io::Error {
 306     io::Error::new(io::ErrorKind::Other, format!("{context}: {err}"))
 307 }