rust/src/librustc_metadata/cstore.rs
2016-02-12 19:28:42 +01:00

344 lines
12 KiB
Rust

// Copyright 2012-2014 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.
#![allow(non_camel_case_types)]
// The crate store - a central repo for information collected about external
// crates and libraries
pub use self::MetadataBlob::*;
use creader;
use decoder;
use index;
use loader;
use rustc::back::svh::Svh;
use rustc::front::map as ast_map;
use rustc::util::nodemap::{FnvHashMap, NodeMap, NodeSet};
use std::cell::{RefCell, Ref, Cell};
use std::rc::Rc;
use std::path::PathBuf;
use flate::Bytes;
use syntax::ast;
use syntax::attr;
use syntax::codemap;
use syntax::parse::token;
use syntax::parse::token::IdentInterner;
use syntax::util::small_vector::SmallVector;
pub use middle::cstore::{NativeLibraryKind, LinkagePreference};
pub use middle::cstore::{NativeStatic, NativeFramework, NativeUnknown};
pub use middle::cstore::{CrateSource, LinkMeta};
// A map from external crate numbers (as decoded from some crate file) to
// local crate numbers (as generated during this session). Each external
// crate may refer to types in other external crates, and each has their
// own crate numbers.
pub type cnum_map = FnvHashMap<ast::CrateNum, ast::CrateNum>;
pub enum MetadataBlob {
MetadataVec(Bytes),
MetadataArchive(loader::ArchiveMetadata),
}
/// Holds information about a codemap::FileMap imported from another crate.
/// See creader::import_codemap() for more information.
pub struct ImportedFileMap {
/// This FileMap's byte-offset within the codemap of its original crate
pub original_start_pos: codemap::BytePos,
/// The end of this FileMap within the codemap of its original crate
pub original_end_pos: codemap::BytePos,
/// The imported FileMap's representation within the local codemap
pub translated_filemap: Rc<codemap::FileMap>
}
pub struct crate_metadata {
pub name: String,
pub local_path: RefCell<SmallVector<ast_map::PathElem>>,
pub local_def_path: RefCell<ast_map::DefPath>,
pub data: MetadataBlob,
pub cnum_map: RefCell<cnum_map>,
pub cnum: ast::CrateNum,
pub codemap_import_info: RefCell<Vec<ImportedFileMap>>,
pub span: codemap::Span,
pub staged_api: bool,
pub index: index::Index,
pub xref_index: index::DenseIndex,
/// Flag if this crate is required by an rlib version of this crate, or in
/// other words whether it was explicitly linked to. An example of a crate
/// where this is false is when an allocator crate is injected into the
/// dependency list, and therefore isn't actually needed to link an rlib.
pub explicitly_linked: Cell<bool>,
}
pub struct CStore {
metas: RefCell<FnvHashMap<ast::CrateNum, Rc<crate_metadata>>>,
/// Map from NodeId's of local extern crate statements to crate numbers
extern_mod_crate_map: RefCell<NodeMap<ast::CrateNum>>,
used_crate_sources: RefCell<Vec<CrateSource>>,
used_libraries: RefCell<Vec<(String, NativeLibraryKind)>>,
used_link_args: RefCell<Vec<String>>,
statically_included_foreign_items: RefCell<NodeSet>,
pub intr: Rc<IdentInterner>,
}
impl CStore {
pub fn new(intr: Rc<IdentInterner>) -> CStore {
CStore {
metas: RefCell::new(FnvHashMap()),
extern_mod_crate_map: RefCell::new(FnvHashMap()),
used_crate_sources: RefCell::new(Vec::new()),
used_libraries: RefCell::new(Vec::new()),
used_link_args: RefCell::new(Vec::new()),
intr: intr,
statically_included_foreign_items: RefCell::new(NodeSet()),
}
}
pub fn next_crate_num(&self) -> ast::CrateNum {
self.metas.borrow().len() as ast::CrateNum + 1
}
pub fn get_crate_data(&self, cnum: ast::CrateNum) -> Rc<crate_metadata> {
self.metas.borrow().get(&cnum).unwrap().clone()
}
pub fn get_crate_hash(&self, cnum: ast::CrateNum) -> Svh {
let cdata = self.get_crate_data(cnum);
decoder::get_crate_hash(cdata.data())
}
pub fn set_crate_data(&self, cnum: ast::CrateNum, data: Rc<crate_metadata>) {
self.metas.borrow_mut().insert(cnum, data);
}
pub fn iter_crate_data<I>(&self, mut i: I) where
I: FnMut(ast::CrateNum, &Rc<crate_metadata>),
{
for (&k, v) in self.metas.borrow().iter() {
i(k, v);
}
}
/// Like `iter_crate_data`, but passes source paths (if available) as well.
pub fn iter_crate_data_origins<I>(&self, mut i: I) where
I: FnMut(ast::CrateNum, &crate_metadata, Option<CrateSource>),
{
for (&k, v) in self.metas.borrow().iter() {
let origin = self.opt_used_crate_source(k);
origin.as_ref().map(|cs| { assert!(k == cs.cnum); });
i(k, &v, origin);
}
}
pub fn add_used_crate_source(&self, src: CrateSource) {
let mut used_crate_sources = self.used_crate_sources.borrow_mut();
if !used_crate_sources.contains(&src) {
used_crate_sources.push(src);
}
}
pub fn opt_used_crate_source(&self, cnum: ast::CrateNum)
-> Option<CrateSource> {
self.used_crate_sources.borrow_mut()
.iter().find(|source| source.cnum == cnum).cloned()
}
pub fn reset(&self) {
self.metas.borrow_mut().clear();
self.extern_mod_crate_map.borrow_mut().clear();
self.used_crate_sources.borrow_mut().clear();
self.used_libraries.borrow_mut().clear();
self.used_link_args.borrow_mut().clear();
self.statically_included_foreign_items.borrow_mut().clear();
}
// This method is used when generating the command line to pass through to
// system linker. The linker expects undefined symbols on the left of the
// command line to be defined in libraries on the right, not the other way
// around. For more info, see some comments in the add_used_library function
// below.
//
// In order to get this left-to-right dependency ordering, we perform a
// topological sort of all crates putting the leaves at the right-most
// positions.
pub fn do_get_used_crates(&self, prefer: LinkagePreference)
-> Vec<(ast::CrateNum, Option<PathBuf>)> {
let mut ordering = Vec::new();
fn visit(cstore: &CStore, cnum: ast::CrateNum,
ordering: &mut Vec<ast::CrateNum>) {
if ordering.contains(&cnum) { return }
let meta = cstore.get_crate_data(cnum);
for (_, &dep) in meta.cnum_map.borrow().iter() {
visit(cstore, dep, ordering);
}
ordering.push(cnum);
}
for (&num, _) in self.metas.borrow().iter() {
visit(self, num, &mut ordering);
}
info!("topological ordering: {:?}", ordering);
ordering.reverse();
let mut libs = self.used_crate_sources.borrow()
.iter()
.map(|src| (src.cnum, match prefer {
LinkagePreference::RequireDynamic => src.dylib.clone().map(|p| p.0),
LinkagePreference::RequireStatic => src.rlib.clone().map(|p| p.0),
}))
.collect::<Vec<_>>();
libs.sort_by(|&(a, _), &(b, _)| {
let a = ordering.iter().position(|x| *x == a);
let b = ordering.iter().position(|x| *x == b);
a.cmp(&b)
});
libs
}
pub fn add_used_library(&self, lib: String, kind: NativeLibraryKind) {
assert!(!lib.is_empty());
self.used_libraries.borrow_mut().push((lib, kind));
}
pub fn get_used_libraries<'a>(&'a self)
-> &'a RefCell<Vec<(String,
NativeLibraryKind)>> {
&self.used_libraries
}
pub fn add_used_link_args(&self, args: &str) {
for s in args.split(' ').filter(|s| !s.is_empty()) {
self.used_link_args.borrow_mut().push(s.to_string());
}
}
pub fn get_used_link_args<'a>(&'a self) -> &'a RefCell<Vec<String> > {
&self.used_link_args
}
pub fn add_extern_mod_stmt_cnum(&self,
emod_id: ast::NodeId,
cnum: ast::CrateNum) {
self.extern_mod_crate_map.borrow_mut().insert(emod_id, cnum);
}
pub fn add_statically_included_foreign_item(&self, id: ast::NodeId) {
self.statically_included_foreign_items.borrow_mut().insert(id);
}
pub fn do_is_statically_included_foreign_item(&self, id: ast::NodeId) -> bool {
self.statically_included_foreign_items.borrow().contains(&id)
}
pub fn do_extern_mod_stmt_cnum(&self, emod_id: ast::NodeId) -> Option<ast::CrateNum>
{
self.extern_mod_crate_map.borrow().get(&emod_id).cloned()
}
}
impl crate_metadata {
pub fn data<'a>(&'a self) -> &'a [u8] { self.data.as_slice() }
pub fn name(&self) -> String { decoder::get_crate_name(self.data()) }
pub fn hash(&self) -> Svh { decoder::get_crate_hash(self.data()) }
pub fn imported_filemaps<'a>(&'a self, codemap: &codemap::CodeMap)
-> Ref<'a, Vec<ImportedFileMap>> {
let filemaps = self.codemap_import_info.borrow();
if filemaps.is_empty() {
drop(filemaps);
let filemaps = creader::import_codemap(codemap, &self.data);
// This shouldn't borrow twice, but there is no way to downgrade RefMut to Ref.
*self.codemap_import_info.borrow_mut() = filemaps;
self.codemap_import_info.borrow()
} else {
filemaps
}
}
pub fn with_local_path<T, F>(&self, f: F) -> T
where F: Fn(&[ast_map::PathElem]) -> T
{
let cpath = self.local_path.borrow();
if cpath.is_empty() {
let name = ast_map::PathMod(token::intern(&self.name));
f(&[name])
} else {
f(cpath.as_slice())
}
}
pub fn update_local_path<'a, 'b>(&self, candidate: ast_map::PathElems<'a, 'b>) {
let mut cpath = self.local_path.borrow_mut();
let cap = cpath.len();
match cap {
0 => *cpath = candidate.collect(),
1 => (),
_ => {
let candidate: SmallVector<_> = candidate.collect();
if candidate.len() < cap {
*cpath = candidate;
}
},
}
}
pub fn local_def_path(&self) -> ast_map::DefPath {
let local_def_path = self.local_def_path.borrow();
if local_def_path.is_empty() {
let name = ast_map::DefPathData::DetachedCrate(token::intern(&self.name));
vec![ast_map::DisambiguatedDefPathData { data: name, disambiguator: 0 }]
} else {
local_def_path.clone()
}
}
pub fn update_local_def_path(&self, candidate: ast_map::DefPath) {
let mut local_def_path = self.local_def_path.borrow_mut();
if local_def_path.is_empty() || candidate.len() < local_def_path.len() {
*local_def_path = candidate;
}
}
pub fn is_allocator(&self) -> bool {
let attrs = decoder::get_crate_attributes(self.data());
attr::contains_name(&attrs, "allocator")
}
pub fn needs_allocator(&self) -> bool {
let attrs = decoder::get_crate_attributes(self.data());
attr::contains_name(&attrs, "needs_allocator")
}
}
impl MetadataBlob {
pub fn as_slice<'a>(&'a self) -> &'a [u8] {
let slice = match *self {
MetadataVec(ref vec) => &vec[..],
MetadataArchive(ref ar) => ar.as_slice(),
};
if slice.len() < 4 {
&[] // corrupt metadata
} else {
let len = (((slice[0] as u32) << 24) |
((slice[1] as u32) << 16) |
((slice[2] as u32) << 8) |
((slice[3] as u32) << 0)) as usize;
if len + 4 <= slice.len() {
&slice[4.. len + 4]
} else {
&[] // corrupt or old metadata
}
}
}
}