1 // Copyright 2015 The Rust Project Developers. See the COPYRIGHT
2 // file at the top-level directory of this distribution and at
3 // http://rust-lang.org/COPYRIGHT.
5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
8 // option. This file may not be copied, modified, or distributed
9 // except according to those terms.
11 // Copyright 2015 The Rust Project Developers. See the COPYRIGHT
12 // file at the top-level directory of this distribution and at
13 // http://rust-lang.org/COPYRIGHT.
15 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
16 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
17 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
18 // option. This file may not be copied, modified, or distributed
19 // except according to those terms.
21 // the rustc crate store interface. This also includes types that
22 // are *mostly* used as a part of that interface, but these should
23 // probably get a better home if someone can find one.
26 use front::map as hir_map;
28 use middle::lang_items;
29 use middle::ty::{self, Ty};
30 use middle::def_id::{DefId, DefIndex};
32 use session::search_paths::PathKind;
33 use util::nodemap::{FnvHashMap, NodeMap, NodeSet};
35 use std::cell::RefCell;
37 use std::path::PathBuf;
39 use syntax::ast_util::{IdVisitingOperation};
41 use syntax::codemap::Span;
43 use rustc_back::target::Target;
45 use rustc_front::intravisit::Visitor;
46 use rustc_front::util::IdVisitor;
48 pub use self::DefLike::{DlDef, DlField, DlImpl};
49 pub use self::NativeLibraryKind::{NativeStatic, NativeFramework, NativeUnknown};
51 // lonely orphan structs and enums looking for a better home
53 #[derive(Clone, Debug)]
55 pub crate_name: String,
59 // Where a crate came from on the local filesystem. One of these two options
61 #[derive(PartialEq, Clone, Debug)]
62 pub struct CrateSource {
63 pub dylib: Option<(PathBuf, PathKind)>,
64 pub rlib: Option<(PathBuf, PathKind)>,
65 pub cnum: ast::CrateNum,
68 #[derive(Copy, Debug, PartialEq, Clone)]
69 pub enum LinkagePreference {
75 #[derive(Copy, Clone, PartialEq)]
76 pub enum NativeLibraryKind {
77 NativeStatic, // native static library (.a archive)
78 NativeFramework, // OSX-specific
79 NativeUnknown, // default way to specify a dynamic library
83 // Something that a name can resolve to.
84 #[derive(Copy, Clone, Debug)]
91 /// The data we save and restore about an inlined item or method. This is not
92 /// part of the AST that we parse from a file, but it becomes part of the tree
94 #[derive(Clone, PartialEq, Eq, RustcEncodable, RustcDecodable, Hash, Debug)]
95 pub enum InlinedItem {
97 TraitItem(DefId /* impl id */, P<hir::TraitItem>),
98 ImplItem(DefId /* impl id */, P<hir::ImplItem>),
99 Foreign(P<hir::ForeignItem>),
102 /// A borrowed version of `hir::InlinedItem`.
103 pub enum InlinedItemRef<'a> {
105 TraitItem(DefId, &'a hir::TraitItem),
106 ImplItem(DefId, &'a hir::ImplItem),
107 Foreign(&'a hir::ForeignItem)
110 /// Item definitions in the currently-compiled crate would have the CrateNum
111 /// LOCAL_CRATE in their DefId.
112 pub const LOCAL_CRATE: ast::CrateNum = 0;
114 pub struct ChildItem {
117 pub vis: hir::Visibility
120 pub enum FoundAst<'ast> {
121 Found(&'ast InlinedItem),
122 FoundParent(DefId, &'ast InlinedItem),
126 /// A store of Rust crates, through with their metadata
129 /// The `: Any` bound is a temporary measure that allows access
130 /// to the backing `rustc_metadata::cstore::CStore` object. It
131 /// will be removed in the near future - if you need to access
132 /// internal APIs, please tell us.
133 pub trait CrateStore<'tcx> : Any {
135 fn stability(&self, def: DefId) -> Option<attr::Stability>;
136 fn closure_kind(&self, tcx: &ty::ctxt<'tcx>, def_id: DefId)
138 fn closure_ty(&self, tcx: &ty::ctxt<'tcx>, def_id: DefId)
139 -> ty::ClosureTy<'tcx>;
140 fn item_variances(&self, def: DefId) -> ty::ItemVariances;
141 fn repr_attrs(&self, def: DefId) -> Vec<attr::ReprAttr>;
142 fn item_type(&self, tcx: &ty::ctxt<'tcx>, def: DefId)
143 -> ty::TypeScheme<'tcx>;
144 fn item_path(&self, def: DefId) -> Vec<hir_map::PathElem>;
145 fn extern_item_path(&self, def: DefId) -> Vec<hir_map::PathElem>;
146 fn item_name(&self, def: DefId) -> ast::Name;
147 fn item_predicates(&self, tcx: &ty::ctxt<'tcx>, def: DefId)
148 -> ty::GenericPredicates<'tcx>;
149 fn item_super_predicates(&self, tcx: &ty::ctxt<'tcx>, def: DefId)
150 -> ty::GenericPredicates<'tcx>;
151 fn item_attrs(&self, def_id: DefId) -> Vec<ast::Attribute>;
152 fn item_symbol(&self, def: DefId) -> String;
153 fn trait_def(&self, tcx: &ty::ctxt<'tcx>, def: DefId)-> ty::TraitDef<'tcx>;
154 fn adt_def(&self, tcx: &ty::ctxt<'tcx>, def: DefId) -> ty::AdtDefMaster<'tcx>;
155 fn method_arg_names(&self, did: DefId) -> Vec<String>;
156 fn inherent_implementations_for_type(&self, def_id: DefId) -> Vec<DefId>;
159 fn implementations_of_trait(&self, def_id: DefId) -> Vec<DefId>;
160 fn provided_trait_methods(&self, tcx: &ty::ctxt<'tcx>, def: DefId)
161 -> Vec<Rc<ty::Method<'tcx>>>;
162 fn trait_item_def_ids(&self, def: DefId)
163 -> Vec<ty::ImplOrTraitItemId>;
166 fn impl_items(&self, impl_def_id: DefId) -> Vec<ty::ImplOrTraitItemId>;
167 fn impl_trait_ref(&self, tcx: &ty::ctxt<'tcx>, def: DefId)
168 -> Option<ty::TraitRef<'tcx>>;
169 fn impl_polarity(&self, def: DefId) -> Option<hir::ImplPolarity>;
170 fn custom_coerce_unsized_kind(&self, def: DefId)
171 -> Option<ty::adjustment::CustomCoerceUnsized>;
172 fn associated_consts(&self, tcx: &ty::ctxt<'tcx>, def: DefId)
173 -> Vec<Rc<ty::AssociatedConst<'tcx>>>;
175 // trait/impl-item info
176 fn trait_of_item(&self, tcx: &ty::ctxt<'tcx>, def_id: DefId)
178 fn impl_or_trait_item(&self, tcx: &ty::ctxt<'tcx>, def: DefId)
179 -> ty::ImplOrTraitItem<'tcx>;
182 fn is_const_fn(&self, did: DefId) -> bool;
183 fn is_defaulted_trait(&self, did: DefId) -> bool;
184 fn is_impl(&self, did: DefId) -> bool;
185 fn is_default_impl(&self, impl_did: DefId) -> bool;
186 fn is_extern_fn(&self, tcx: &ty::ctxt<'tcx>, did: DefId) -> bool;
187 fn is_static(&self, did: DefId) -> bool;
188 fn is_static_method(&self, did: DefId) -> bool;
189 fn is_statically_included_foreign_item(&self, id: ast::NodeId) -> bool;
190 fn is_typedef(&self, did: DefId) -> bool;
193 fn dylib_dependency_formats(&self, cnum: ast::CrateNum)
194 -> Vec<(ast::CrateNum, LinkagePreference)>;
195 fn lang_items(&self, cnum: ast::CrateNum) -> Vec<(DefIndex, usize)>;
196 fn missing_lang_items(&self, cnum: ast::CrateNum) -> Vec<lang_items::LangItem>;
197 fn is_staged_api(&self, cnum: ast::CrateNum) -> bool;
198 fn is_explicitly_linked(&self, cnum: ast::CrateNum) -> bool;
199 fn is_allocator(&self, cnum: ast::CrateNum) -> bool;
200 fn crate_attrs(&self, cnum: ast::CrateNum) -> Vec<ast::Attribute>;
201 fn crate_name(&self, cnum: ast::CrateNum) -> String;
202 fn crate_hash(&self, cnum: ast::CrateNum) -> Svh;
203 fn crate_struct_field_attrs(&self, cnum: ast::CrateNum)
204 -> FnvHashMap<DefId, Vec<ast::Attribute>>;
205 fn plugin_registrar_fn(&self, cnum: ast::CrateNum) -> Option<DefId>;
206 fn native_libraries(&self, cnum: ast::CrateNum) -> Vec<(NativeLibraryKind, String)>;
207 fn reachable_ids(&self, cnum: ast::CrateNum) -> Vec<DefId>;
210 fn def_path(&self, def: DefId) -> hir_map::DefPath;
211 fn tuple_struct_definition_if_ctor(&self, did: DefId) -> Option<DefId>;
212 fn struct_field_names(&self, def: DefId) -> Vec<ast::Name>;
213 fn item_children(&self, did: DefId) -> Vec<ChildItem>;
214 fn crate_top_level_items(&self, cnum: ast::CrateNum) -> Vec<ChildItem>;
217 fn maybe_get_item_ast(&'tcx self, tcx: &ty::ctxt<'tcx>, def: DefId)
219 // This is basically a 1-based range of ints, which is a little
220 // silly - I may fix that.
221 fn crates(&self) -> Vec<ast::CrateNum>;
222 fn used_libraries(&self) -> Vec<(String, NativeLibraryKind)>;
223 fn used_link_args(&self) -> Vec<String>;
226 fn metadata_filename(&self) -> &str;
227 fn metadata_section_name(&self, target: &Target) -> &str;
228 fn encode_type(&self, tcx: &ty::ctxt<'tcx>, ty: Ty<'tcx>) -> Vec<u8>;
229 fn used_crates(&self, prefer: LinkagePreference) -> Vec<(ast::CrateNum, Option<PathBuf>)>;
230 fn used_crate_source(&self, cnum: ast::CrateNum) -> CrateSource;
231 fn extern_mod_stmt_cnum(&self, emod_id: ast::NodeId) -> Option<ast::CrateNum>;
232 fn encode_metadata(&self,
233 tcx: &ty::ctxt<'tcx>,
234 reexports: &def::ExportMap,
235 item_symbols: &RefCell<NodeMap<String>>,
236 link_meta: &LinkMeta,
238 krate: &hir::Crate) -> Vec<u8>;
239 fn metadata_encoding_version(&self) -> &[u8];
243 pub fn visit<'ast,V>(&'ast self, visitor: &mut V)
244 where V: Visitor<'ast>
247 InlinedItem::Item(ref i) => visitor.visit_item(&**i),
248 InlinedItem::Foreign(ref i) => visitor.visit_foreign_item(&**i),
249 InlinedItem::TraitItem(_, ref ti) => visitor.visit_trait_item(ti),
250 InlinedItem::ImplItem(_, ref ii) => visitor.visit_impl_item(ii),
254 pub fn visit_ids<O: IdVisitingOperation>(&self, operation: &mut O) {
255 let mut id_visitor = IdVisitor::new(operation);
256 self.visit(&mut id_visitor);
260 // FIXME: find a better place for this?
261 pub fn validate_crate_name(sess: Option<&Session>, s: &str, sp: Option<Span>) {
262 let say = |s: &str| {
264 (_, None) => panic!("{}", s),
265 (Some(sp), Some(sess)) => sess.span_err(sp, s),
266 (None, Some(sess)) => sess.err(s),
270 say("crate name must not be empty");
273 if c.is_alphanumeric() { continue }
274 if c == '_' { continue }
275 say(&format!("invalid character `{}` in crate name: `{}`", c, s));
278 Some(sess) => sess.abort_if_errors(),
283 /// A dummy crate store that does not support any non-local crates,
284 /// for test purposes.
285 pub struct DummyCrateStore;
286 #[allow(unused_variables)]
287 impl<'tcx> CrateStore<'tcx> for DummyCrateStore {
289 fn stability(&self, def: DefId) -> Option<attr::Stability> { unimplemented!() }
290 fn closure_kind(&self, tcx: &ty::ctxt<'tcx>, def_id: DefId)
291 -> ty::ClosureKind { unimplemented!() }
292 fn closure_ty(&self, tcx: &ty::ctxt<'tcx>, def_id: DefId)
293 -> ty::ClosureTy<'tcx> { unimplemented!() }
294 fn item_variances(&self, def: DefId) -> ty::ItemVariances { unimplemented!() }
295 fn repr_attrs(&self, def: DefId) -> Vec<attr::ReprAttr> { unimplemented!() }
296 fn item_type(&self, tcx: &ty::ctxt<'tcx>, def: DefId)
297 -> ty::TypeScheme<'tcx> { unimplemented!() }
298 fn item_path(&self, def: DefId) -> Vec<hir_map::PathElem> { unimplemented!() }
299 fn extern_item_path(&self, def: DefId) -> Vec<hir_map::PathElem> { unimplemented!() }
300 fn item_name(&self, def: DefId) -> ast::Name { unimplemented!() }
301 fn item_predicates(&self, tcx: &ty::ctxt<'tcx>, def: DefId)
302 -> ty::GenericPredicates<'tcx> { unimplemented!() }
303 fn item_super_predicates(&self, tcx: &ty::ctxt<'tcx>, def: DefId)
304 -> ty::GenericPredicates<'tcx> { unimplemented!() }
305 fn item_attrs(&self, def_id: DefId) -> Vec<ast::Attribute> { unimplemented!() }
306 fn item_symbol(&self, def: DefId) -> String { unimplemented!() }
307 fn trait_def(&self, tcx: &ty::ctxt<'tcx>, def: DefId)-> ty::TraitDef<'tcx>
309 fn adt_def(&self, tcx: &ty::ctxt<'tcx>, def: DefId) -> ty::AdtDefMaster<'tcx>
311 fn method_arg_names(&self, did: DefId) -> Vec<String> { unimplemented!() }
312 fn inherent_implementations_for_type(&self, def_id: DefId) -> Vec<DefId> { vec![] }
315 fn implementations_of_trait(&self, def_id: DefId) -> Vec<DefId> { vec![] }
316 fn provided_trait_methods(&self, tcx: &ty::ctxt<'tcx>, def: DefId)
317 -> Vec<Rc<ty::Method<'tcx>>> { unimplemented!() }
318 fn trait_item_def_ids(&self, def: DefId)
319 -> Vec<ty::ImplOrTraitItemId> { unimplemented!() }
322 fn impl_items(&self, impl_def_id: DefId) -> Vec<ty::ImplOrTraitItemId>
324 fn impl_trait_ref(&self, tcx: &ty::ctxt<'tcx>, def: DefId)
325 -> Option<ty::TraitRef<'tcx>> { unimplemented!() }
326 fn impl_polarity(&self, def: DefId) -> Option<hir::ImplPolarity> { unimplemented!() }
327 fn custom_coerce_unsized_kind(&self, def: DefId)
328 -> Option<ty::adjustment::CustomCoerceUnsized>
330 fn associated_consts(&self, tcx: &ty::ctxt<'tcx>, def: DefId)
331 -> Vec<Rc<ty::AssociatedConst<'tcx>>> { unimplemented!() }
333 // trait/impl-item info
334 fn trait_of_item(&self, tcx: &ty::ctxt<'tcx>, def_id: DefId)
335 -> Option<DefId> { unimplemented!() }
336 fn impl_or_trait_item(&self, tcx: &ty::ctxt<'tcx>, def: DefId)
337 -> ty::ImplOrTraitItem<'tcx> { unimplemented!() }
340 fn is_const_fn(&self, did: DefId) -> bool { unimplemented!() }
341 fn is_defaulted_trait(&self, did: DefId) -> bool { unimplemented!() }
342 fn is_impl(&self, did: DefId) -> bool { unimplemented!() }
343 fn is_default_impl(&self, impl_did: DefId) -> bool { unimplemented!() }
344 fn is_extern_fn(&self, tcx: &ty::ctxt<'tcx>, did: DefId) -> bool { unimplemented!() }
345 fn is_static(&self, did: DefId) -> bool { unimplemented!() }
346 fn is_static_method(&self, did: DefId) -> bool { unimplemented!() }
347 fn is_statically_included_foreign_item(&self, id: ast::NodeId) -> bool { false }
348 fn is_typedef(&self, did: DefId) -> bool { unimplemented!() }
351 fn dylib_dependency_formats(&self, cnum: ast::CrateNum)
352 -> Vec<(ast::CrateNum, LinkagePreference)>
354 fn lang_items(&self, cnum: ast::CrateNum) -> Vec<(DefIndex, usize)>
356 fn missing_lang_items(&self, cnum: ast::CrateNum) -> Vec<lang_items::LangItem>
358 fn is_staged_api(&self, cnum: ast::CrateNum) -> bool { unimplemented!() }
359 fn is_explicitly_linked(&self, cnum: ast::CrateNum) -> bool { unimplemented!() }
360 fn is_allocator(&self, cnum: ast::CrateNum) -> bool { unimplemented!() }
361 fn crate_attrs(&self, cnum: ast::CrateNum) -> Vec<ast::Attribute>
363 fn crate_name(&self, cnum: ast::CrateNum) -> String { unimplemented!() }
364 fn crate_hash(&self, cnum: ast::CrateNum) -> Svh { unimplemented!() }
365 fn crate_struct_field_attrs(&self, cnum: ast::CrateNum)
366 -> FnvHashMap<DefId, Vec<ast::Attribute>>
368 fn plugin_registrar_fn(&self, cnum: ast::CrateNum) -> Option<DefId>
370 fn native_libraries(&self, cnum: ast::CrateNum) -> Vec<(NativeLibraryKind, String)>
372 fn reachable_ids(&self, cnum: ast::CrateNum) -> Vec<DefId> { unimplemented!() }
375 fn def_path(&self, def: DefId) -> hir_map::DefPath { unimplemented!() }
376 fn tuple_struct_definition_if_ctor(&self, did: DefId) -> Option<DefId>
378 fn struct_field_names(&self, def: DefId) -> Vec<ast::Name> { unimplemented!() }
379 fn item_children(&self, did: DefId) -> Vec<ChildItem> { unimplemented!() }
380 fn crate_top_level_items(&self, cnum: ast::CrateNum) -> Vec<ChildItem>
384 fn maybe_get_item_ast(&'tcx self, tcx: &ty::ctxt<'tcx>, def: DefId)
385 -> FoundAst<'tcx> { unimplemented!() }
386 // This is basically a 1-based range of ints, which is a little
387 // silly - I may fix that.
388 fn crates(&self) -> Vec<ast::CrateNum> { vec![] }
389 fn used_libraries(&self) -> Vec<(String, NativeLibraryKind)> { vec![] }
390 fn used_link_args(&self) -> Vec<String> { vec![] }
393 fn metadata_filename(&self) -> &str { unimplemented!() }
394 fn metadata_section_name(&self, target: &Target) -> &str { unimplemented!() }
395 fn encode_type(&self, tcx: &ty::ctxt<'tcx>, ty: Ty<'tcx>) -> Vec<u8>
397 fn used_crates(&self, prefer: LinkagePreference) -> Vec<(ast::CrateNum, Option<PathBuf>)>
399 fn used_crate_source(&self, cnum: ast::CrateNum) -> CrateSource { unimplemented!() }
400 fn extern_mod_stmt_cnum(&self, emod_id: ast::NodeId) -> Option<ast::CrateNum> { None }
401 fn encode_metadata(&self,
402 tcx: &ty::ctxt<'tcx>,
403 reexports: &def::ExportMap,
404 item_symbols: &RefCell<NodeMap<String>>,
405 link_meta: &LinkMeta,
407 krate: &hir::Crate) -> Vec<u8> { vec![] }
408 fn metadata_encoding_version(&self) -> &[u8] { unimplemented!() }
412 /// Metadata encoding and decoding can make use of thread-local encoding and
413 /// decoding contexts. These allow implementers of serialize::Encodable and
414 /// Decodable to access information and datastructures that would otherwise not
415 /// be available to them. For example, we can automatically translate def-id and
416 /// span information during decoding because the decoding context knows which
417 /// crate the data is decoded from. Or it allows to make ty::Ty decodable
418 /// because the context has access to the ty::ctxt that is needed for creating
419 /// ty::Ty instances.
421 /// Note, however, that this only works for RBML-based encoding and decoding at
424 use rbml::writer::Encoder as RbmlEncoder;
425 use rbml::reader::Decoder as RbmlDecoder;
428 use middle::ty::{self, Ty};
429 use middle::subst::Substs;
430 use middle::def_id::DefId;
432 pub trait EncodingContext<'tcx> {
433 fn tcx<'a>(&'a self) -> &'a ty::ctxt<'tcx>;
434 fn encode_ty(&self, rbml_w: &mut RbmlEncoder, t: Ty<'tcx>);
435 fn encode_substs(&self, rbml_w: &mut RbmlEncoder, substs: &Substs<'tcx>);
438 /// Marker type used for the scoped TLS slot.
439 /// The type context cannot be used directly because the scoped TLS
440 /// in libstd doesn't allow types generic over lifetimes.
443 scoped_thread_local!(static TLS_ENCODING: TlsPayload);
445 /// Execute f after pushing the given EncodingContext onto the TLS stack.
446 pub fn enter_encoding_context<'tcx, F, R>(ecx: &EncodingContext<'tcx>,
447 rbml_w: &mut RbmlEncoder,
449 where F: FnOnce(&EncodingContext<'tcx>, &mut RbmlEncoder) -> R
451 let tls_payload = (ecx as *const _, rbml_w as *mut _);
452 let tls_ptr = &tls_payload as *const _ as *const TlsPayload;
453 TLS_ENCODING.set(unsafe { &*tls_ptr }, || f(ecx, rbml_w))
456 /// Execute f with access to the thread-local encoding context and
457 /// rbml encoder. This function will panic if the encoder passed in and the
458 /// context encoder are not the same.
460 /// Note that this method is 'practically' safe due to its checking that the
461 /// encoder passed in is the same as the one in TLS, but it would still be
462 /// possible to construct cases where the EncodingContext is exchanged
463 /// while the same encoder is used, thus working with a wrong context.
464 pub fn with_encoding_context<'tcx, E, F, R>(encoder: &mut E, f: F) -> R
465 where F: FnOnce(&EncodingContext<'tcx>, &mut RbmlEncoder) -> R,
466 E: serialize::Encoder
469 unsafe_with_encoding_context(|ecx, rbml_w| {
470 assert!(encoder as *mut _ as usize == rbml_w as *mut _ as usize);
472 let ecx: &EncodingContext<'tcx> = mem::transmute(ecx);
479 /// Execute f with access to the thread-local encoding context and
481 pub unsafe fn unsafe_with_encoding_context<F, R>(f: F) -> R
482 where F: FnOnce(&EncodingContext, &mut RbmlEncoder) -> R
484 TLS_ENCODING.with(|tls| {
485 let tls_payload = (tls as *const TlsPayload)
486 as *mut (&EncodingContext, &mut RbmlEncoder);
487 f((*tls_payload).0, (*tls_payload).1)
491 pub trait DecodingContext<'tcx> {
492 fn tcx<'a>(&'a self) -> &'a ty::ctxt<'tcx>;
493 fn decode_ty(&self, rbml_r: &mut RbmlDecoder) -> ty::Ty<'tcx>;
494 fn decode_substs(&self, rbml_r: &mut RbmlDecoder) -> Substs<'tcx>;
495 fn translate_def_id(&self, def_id: DefId) -> DefId;
498 scoped_thread_local!(static TLS_DECODING: TlsPayload);
500 /// Execute f after pushing the given DecodingContext onto the TLS stack.
501 pub fn enter_decoding_context<'tcx, F, R>(dcx: &DecodingContext<'tcx>,
502 rbml_r: &mut RbmlDecoder,
504 where F: FnOnce(&DecodingContext<'tcx>, &mut RbmlDecoder) -> R
506 let tls_payload = (dcx as *const _, rbml_r as *mut _);
507 let tls_ptr = &tls_payload as *const _ as *const TlsPayload;
508 TLS_DECODING.set(unsafe { &*tls_ptr }, || f(dcx, rbml_r))
511 /// Execute f with access to the thread-local decoding context and
512 /// rbml decoder. This function will panic if the decoder passed in and the
513 /// context decoder are not the same.
515 /// Note that this method is 'practically' safe due to its checking that the
516 /// decoder passed in is the same as the one in TLS, but it would still be
517 /// possible to construct cases where the DecodingContext is exchanged
518 /// while the same decoder is used, thus working with a wrong context.
519 pub fn with_decoding_context<'decoder, 'tcx, D, F, R>(d: &'decoder mut D, f: F) -> R
520 where D: serialize::Decoder,
521 F: FnOnce(&DecodingContext<'tcx>,
522 &mut RbmlDecoder) -> R,
526 unsafe_with_decoding_context(|dcx, rbml_r| {
527 assert!((d as *mut _ as usize) == (rbml_r as *mut _ as usize));
529 let dcx: &DecodingContext<'tcx> = mem::transmute(dcx);
536 /// Execute f with access to the thread-local decoding context and
538 pub unsafe fn unsafe_with_decoding_context<F, R>(f: F) -> R
539 where F: FnOnce(&DecodingContext, &mut RbmlDecoder) -> R
541 TLS_DECODING.with(|tls| {
542 let tls_payload = (tls as *const TlsPayload)
543 as *mut (&DecodingContext, &mut RbmlDecoder);
544 f((*tls_payload).0, (*tls_payload).1)