rust/src/librustc/metadata/creader.rs
2013-04-27 21:34:24 -04:00

339 lines
11 KiB
Rust

// Copyright 2012 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.
//! Validates all used crates and extern libraries and loads their metadata
use metadata::cstore;
use metadata::decoder;
use metadata::filesearch::FileSearch;
use metadata::loader;
use core::hashmap::HashMap;
use syntax::attr;
use syntax::codemap::{span, dummy_sp};
use syntax::diagnostic::span_handler;
use syntax::parse::token::ident_interner;
use syntax::visit;
use syntax::ast;
// Traverses an AST, reading all the information about use'd crates and extern
// libraries necessary for later resolving, typechecking, linking, etc.
pub fn read_crates(diag: @span_handler,
crate: @ast::crate,
cstore: @mut cstore::CStore,
filesearch: @FileSearch,
os: loader::os,
statik: bool,
intr: @ident_interner) {
let e = @mut Env {
diag: diag,
filesearch: filesearch,
cstore: cstore,
os: os,
statik: statik,
crate_cache: @mut ~[],
next_crate_num: 1,
intr: intr
};
let v =
visit::mk_simple_visitor(@visit::SimpleVisitor {
visit_view_item: |a| visit_view_item(e, a),
visit_item: |a| visit_item(e, a),
.. *visit::default_simple_visitor()});
visit_crate(e, crate);
visit::visit_crate(crate, (), v);
dump_crates(e.crate_cache);
warn_if_multiple_versions(e, diag, e.crate_cache);
}
struct cache_entry {
cnum: int,
span: span,
hash: @~str,
metas: @~[@ast::meta_item]
}
fn dump_crates(crate_cache: @mut ~[cache_entry]) {
debug!("resolved crates:");
for crate_cache.each |entry| {
debug!("cnum: %?", entry.cnum);
debug!("span: %?", entry.span);
debug!("hash: %?", entry.hash);
}
}
fn warn_if_multiple_versions(e: @mut Env,
diag: @span_handler,
crate_cache: @mut ~[cache_entry]) {
use core::either::*;
let crate_cache = &mut *crate_cache;
if crate_cache.len() != 0u {
let name = loader::crate_name_from_metas(
*crate_cache[crate_cache.len() - 1].metas
);
let (matches, non_matches) =
partition(crate_cache.map_to_vec(|&entry| {
let othername = loader::crate_name_from_metas(
copy *entry.metas);
if name == othername {
Left(entry)
} else {
Right(entry)
}
}));
assert!(!matches.is_empty());
if matches.len() != 1u {
diag.handler().warn(
fmt!("using multiple versions of crate `%s`", *name));
for matches.each |match_| {
diag.span_note(match_.span, ~"used here");
let attrs = ~[
attr::mk_attr(attr::mk_list_item(
@~"link", /*bad*/copy *match_.metas))
];
loader::note_linkage_attrs(e.intr, diag, attrs);
}
}
warn_if_multiple_versions(e, diag, @mut non_matches);
}
}
struct Env {
diag: @span_handler,
filesearch: @FileSearch,
cstore: @mut cstore::CStore,
os: loader::os,
statik: bool,
crate_cache: @mut ~[cache_entry],
next_crate_num: ast::crate_num,
intr: @ident_interner
}
fn visit_crate(e: @mut Env, c: &ast::crate) {
let cstore = e.cstore;
let link_args = attr::find_attrs_by_name(c.node.attrs, "link_args");
for link_args.each |a| {
match attr::get_meta_item_value_str(attr::attr_meta(*a)) {
Some(ref linkarg) => {
cstore::add_used_link_args(cstore, **linkarg);
}
None => {/* fallthrough */ }
}
}
}
fn visit_view_item(e: @mut Env, i: @ast::view_item) {
match i.node {
ast::view_item_extern_mod(ident, /*bad*/copy meta_items, id) => {
debug!("resolving extern mod stmt. ident: %?, meta: %?",
ident, meta_items);
let cnum = resolve_crate(e, ident, meta_items, @~"", i.span);
cstore::add_extern_mod_stmt_cnum(e.cstore, id, cnum);
}
_ => ()
}
}
fn visit_item(e: @mut Env, i: @ast::item) {
match i.node {
ast::item_foreign_mod(ref fm) => {
if fm.abis.is_rust() || fm.abis.is_intrinsic() {
return;
}
let cstore = e.cstore;
let mut already_added = false;
let link_args = attr::find_attrs_by_name(i.attrs, "link_args");
match fm.sort {
ast::named => {
let foreign_name =
match attr::first_attr_value_str_by_name(i.attrs,
~"link_name") {
Some(nn) => {
if *nn == ~"" {
e.diag.span_fatal(
i.span,
~"empty #[link_name] not allowed; use " +
~"#[nolink].");
}
nn
}
None => e.intr.get(i.ident)
};
if attr::find_attrs_by_name(i.attrs, ~"nolink").is_empty() {
already_added =
!cstore::add_used_library(cstore, foreign_name);
}
if !link_args.is_empty() && already_added {
e.diag.span_fatal(i.span, ~"library '" + *foreign_name +
~"' already added: can't specify link_args.");
}
}
ast::anonymous => { /* do nothing */ }
}
for link_args.each |a| {
match attr::get_meta_item_value_str(attr::attr_meta(*a)) {
Some(linkarg) => {
cstore::add_used_link_args(cstore, *linkarg);
}
None => { /* fallthrough */ }
}
}
}
_ => { }
}
}
fn metas_with(ident: @~str, key: @~str, metas: ~[@ast::meta_item])
-> ~[@ast::meta_item] {
let name_items = attr::find_meta_items_by_name(metas, *key);
if name_items.is_empty() {
vec::append_one(metas, attr::mk_name_value_item_str(key, ident))
} else {
metas
}
}
fn metas_with_ident(ident: @~str, metas: ~[@ast::meta_item])
-> ~[@ast::meta_item] {
metas_with(ident, @~"name", metas)
}
fn existing_match(e: @mut Env, metas: &[@ast::meta_item], hash: @~str)
-> Option<int> {
for e.crate_cache.each |c| {
if loader::metadata_matches(*c.metas, metas)
&& (hash.is_empty() || c.hash == hash) {
return Some(c.cnum);
}
}
return None;
}
fn resolve_crate(e: @mut Env,
ident: ast::ident,
metas: ~[@ast::meta_item],
hash: @~str,
span: span)
-> ast::crate_num {
let metas = metas_with_ident(@/*bad*/copy *e.intr.get(ident), metas);
match existing_match(e, metas, hash) {
None => {
let load_ctxt = loader::Context {
diag: e.diag,
filesearch: e.filesearch,
span: span,
ident: ident,
metas: metas,
hash: hash,
os: e.os,
is_static: e.statik,
intr: e.intr
};
let (lident, ldata) = loader::load_library_crate(&load_ctxt);
let cfilename = Path(lident);
let cdata = ldata;
let attrs = decoder::get_crate_attributes(cdata);
let linkage_metas = attr::find_linkage_metas(attrs);
let hash = decoder::get_crate_hash(cdata);
// Claim this crate number and cache it
let cnum = e.next_crate_num;
e.crate_cache.push(cache_entry {
cnum: cnum,
span: span,
hash: hash,
metas: @linkage_metas
});
e.next_crate_num += 1;
// Now resolve the crates referenced by this crate
let cnum_map = resolve_crate_deps(e, cdata);
let cname =
match attr::last_meta_item_value_str_by_name(load_ctxt.metas,
~"name") {
Some(v) => v,
None => e.intr.get(ident),
};
let cmeta = @cstore::crate_metadata {
name: cname,
data: cdata,
cnum_map: cnum_map,
cnum: cnum
};
let cstore = e.cstore;
cstore::set_crate_data(cstore, cnum, cmeta);
cstore::add_used_crate_file(cstore, &cfilename);
return cnum;
}
Some(cnum) => {
return cnum;
}
}
}
// Go through the crate metadata and load any crates that it references
fn resolve_crate_deps(e: @mut Env, cdata: @~[u8]) -> cstore::cnum_map {
debug!("resolving deps of external crate");
// The map from crate numbers in the crate we're resolving to local crate
// numbers
let mut cnum_map = HashMap::new();
for decoder::get_crate_deps(e.intr, cdata).each |dep| {
let extrn_cnum = dep.cnum;
let cname = dep.name;
let cmetas = metas_with(dep.vers, @~"vers", ~[]);
debug!("resolving dep crate %s ver: %s hash: %s",
*e.intr.get(dep.name), *dep.vers, *dep.hash);
match existing_match(e, metas_with_ident(e.intr.get(cname),
copy cmetas),
dep.hash) {
Some(local_cnum) => {
debug!("already have it");
// We've already seen this crate
cnum_map.insert(extrn_cnum, local_cnum);
}
None => {
debug!("need to load it");
// This is a new one so we've got to load it
// FIXME (#2404): Need better error reporting than just a bogus
// span.
let fake_span = dummy_sp();
let local_cnum = resolve_crate(e, cname, cmetas, dep.hash,
fake_span);
cnum_map.insert(extrn_cnum, local_cnum);
}
}
}
return @mut cnum_map;
}
// Local Variables:
// mode: rust
// fill-column: 78;
// indent-tabs-mode: nil
// c-basic-offset: 4
// buffer-file-coding-system: utf-8-unix
// End: