diff options
| -rw-r--r-- | Cargo.lock | 10 | ||||
| -rw-r--r-- | Cargo.toml | 3 | ||||
| -rw-r--r-- | src/metadata.rs | 70 |
3 files changed, 56 insertions, 27 deletions
diff --git a/Cargo.lock b/Cargo.lock index 1ed186032ff..a033912364e 100644 --- a/Cargo.lock +++ b/Cargo.lock @@ -241,6 +241,15 @@ dependencies = [ ] [[package]] +name = "memmap2" +version = "0.2.1" +source = "registry+https://github.com/rust-lang/crates.io-index" +checksum = "04e3e85b970d650e2ae6d70592474087051c11c54da7f7b4949725c5735fbcc6" +dependencies = [ + "libc", +] + +[[package]] name = "object" version = "0.23.0" source = "registry+https://github.com/rust-lang/crates.io-index" @@ -310,6 +319,7 @@ dependencies = [ "gimli", "indexmap", "libloading", + "memmap2", "object", "smallvec", "target-lexicon", diff --git a/Cargo.toml b/Cargo.toml index e51714b56d7..59542c414fa 100644 --- a/Cargo.toml +++ b/Cargo.toml @@ -16,12 +16,13 @@ cranelift-jit = { git = "https://github.com/bytecodealliance/wasmtime/", branch cranelift-object = { git = "https://github.com/bytecodealliance/wasmtime/", branch = "main" } target-lexicon = "0.11.0" gimli = { version = "0.23.0", default-features = false, features = ["write"]} -object = { version = "0.23.0", default-features = false, features = ["std", "read_core", "write", "coff", "elf", "macho", "pe"] } +object = { version = "0.23.0", default-features = false, features = ["std", "read_core", "write", "archive", "coff", "elf", "macho", "pe"] } ar = { git = "https://github.com/bjorn3/rust-ar.git", branch = "do_not_remove_cg_clif_ranlib" } indexmap = "1.0.2" libloading = { version = "0.6.0", optional = true } smallvec = "1.6.1" +memmap2 = "0.2.1" # Uncomment to use local checkout of cranelift #[patch."https://github.com/bytecodealliance/wasmtime/"] diff --git a/src/metadata.rs b/src/metadata.rs index 190c4f45cca..dda9285a38a 100644 --- a/src/metadata.rs +++ b/src/metadata.rs @@ -1,11 +1,11 @@ //! Reading and writing of the rustc metadata for rlibs and dylibs -use std::convert::TryFrom; use std::fs::File; +use std::ops::Deref; use std::path::Path; use rustc_codegen_ssa::METADATA_FILENAME; -use rustc_data_structures::owning_ref::OwningRef; +use rustc_data_structures::owning_ref::{OwningRef, StableAddress}; use rustc_data_structures::rustc_erase_owner; use rustc_data_structures::sync::MetadataRef; use rustc_middle::middle::cstore::{EncodedMetadata, MetadataLoader}; @@ -17,38 +17,56 @@ use crate::backend::WriteMetadata; pub(crate) struct CraneliftMetadataLoader; +struct StableMmap(memmap2::Mmap); + +impl Deref for StableMmap { + type Target = [u8]; + + fn deref(&self) -> &[u8] { + &*self.0 + } +} + +unsafe impl StableAddress for StableMmap {} + +fn load_metadata_with( + path: &Path, + f: impl for<'a> FnOnce(&'a [u8]) -> Result<&'a [u8], String>, +) -> Result<MetadataRef, String> { + let file = File::open(path).map_err(|e| format!("{:?}", e))?; + let data = unsafe { memmap2::MmapOptions::new().map_copy_read_only(&file) } + .map_err(|e| format!("{:?}", e))?; + let metadata = OwningRef::new(StableMmap(data)).try_map(f)?; + return Ok(rustc_erase_owner!(metadata.map_owner_box())); +} + impl MetadataLoader for CraneliftMetadataLoader { fn get_rlib_metadata(&self, _target: &Target, path: &Path) -> Result<MetadataRef, String> { - let mut archive = ar::Archive::new(File::open(path).map_err(|e| format!("{:?}", e))?); - // Iterate over all entries in the archive: - while let Some(entry_result) = archive.next_entry() { - let mut entry = entry_result.map_err(|e| format!("{:?}", e))?; - if entry.header().identifier() == METADATA_FILENAME.as_bytes() { - let mut buf = Vec::with_capacity( - usize::try_from(entry.header().size()) - .expect("Rlib metadata file too big to load into memory."), - ); - ::std::io::copy(&mut entry, &mut buf).map_err(|e| format!("{:?}", e))?; - let buf: OwningRef<Vec<u8>, [u8]> = OwningRef::new(buf); - return Ok(rustc_erase_owner!(buf.map_owner_box())); + load_metadata_with(path, |data| { + let archive = object::read::archive::ArchiveFile::parse(&*data) + .map_err(|e| format!("{:?}", e))?; + + for entry_result in archive.members() { + let entry = entry_result.map_err(|e| format!("{:?}", e))?; + if entry.name() == METADATA_FILENAME.as_bytes() { + return Ok(entry.data()); + } } - } - Err("couldn't find metadata entry".to_string()) + Err("couldn't find metadata entry".to_string()) + }) } fn get_dylib_metadata(&self, _target: &Target, path: &Path) -> Result<MetadataRef, String> { use object::{Object, ObjectSection}; - let file = std::fs::read(path).map_err(|e| format!("read:{:?}", e))?; - let file = object::File::parse(&file).map_err(|e| format!("parse: {:?}", e))?; - let buf = file - .section_by_name(".rustc") - .ok_or("no .rustc section")? - .data() - .map_err(|e| format!("failed to read .rustc section: {:?}", e))? - .to_owned(); - let buf: OwningRef<Vec<u8>, [u8]> = OwningRef::new(buf); - Ok(rustc_erase_owner!(buf.map_owner_box())) + + load_metadata_with(path, |data| { + let file = object::File::parse(&data).map_err(|e| format!("parse: {:?}", e))?; + file.section_by_name(".rustc") + .ok_or("no .rustc section")? + .data() + .map_err(|e| format!("failed to read .rustc section: {:?}", e)) + }) } } |