src/metadata.rs

   1 use rustc::middle::cstore::MetadataLoader;
   2 use rustc_data_structures::owning_ref::{self, OwningRef};
   3 use std::fs::File;
   4 use std::path::Path;
   5
   6 pub const METADATA_FILE: &'static [u8] = b"rust.metadata.bin" as &[u8];
   7
   8 pub struct CraneliftMetadataLoader;
   9
  10 impl MetadataLoader for CraneliftMetadataLoader {
  11     fn get_rlib_metadata(
  12         &self,
  13         _target: &crate::rustc_target::spec::Target,
  14         path: &Path,
  15     ) -> Result<owning_ref::ErasedBoxRef<[u8]>, String> {
  16         let mut archive = ar::Archive::new(File::open(path).map_err(|e| format!("{:?}", e))?);
  17         // Iterate over all entries in the archive:
  18         while let Some(entry_result) = archive.next_entry() {
  19             let mut entry = entry_result.map_err(|e| format!("{:?}", e))?;
  20             if entry
  21                 .header()
  22                 .identifier() == METADATA_FILE
  23             {
  24                 let mut buf = Vec::new();
  25                 ::std::io::copy(&mut entry, &mut buf).map_err(|e| format!("{:?}", e))?;
  26                 let buf: OwningRef<Vec<u8>, [u8]> = OwningRef::new(buf).into();
  27                 return Ok(rustc_erase_owner!(buf.map_owner_box()));
  28             }
  29         }
  30
  31         Err("couldn't find metadata entry".to_string())
  32         //self.get_dylib_metadata(target, path)
  33     }
  34
  35     fn get_dylib_metadata(
  36         &self,
  37         _target: &crate::rustc_target::spec::Target,
  38         _path: &Path,
  39     ) -> Result<owning_ref::ErasedBoxRef<[u8]>, String> {
  40         Err("dylib metadata loading is not yet supported".to_string())
  41     }
  42 }