1 // Copyright 2012 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.
13 Runtime type reflection
17 #![allow(missing_doc)]
19 use intrinsics::{Disr, Opaque, TyDesc, TyVisitor};
24 * Trait for visitor that wishes to reflect on data. To use this, create a
25 * struct that encapsulates the set of pointers you wish to walk through a
26 * data structure, and implement both `MovePtr` for it as well as `TyVisitor`;
27 * then build a MovePtrAdaptor wrapped around your struct.
30 fn move_ptr(&mut self, adjustment: |*u8| -> *u8);
31 fn push_ptr(&mut self);
32 fn pop_ptr(&mut self);
35 /// Helper function for alignment calculation.
37 pub fn align(size: uint, align: uint) -> uint {
38 ((size + align) - 1u) & !(align - 1u)
41 /// Adaptor to wrap around visitors implementing MovePtr.
42 pub struct MovePtrAdaptor<V> {
45 pub fn MovePtrAdaptor<V:TyVisitor + MovePtr>(v: V) -> MovePtrAdaptor<V> {
46 MovePtrAdaptor { inner: v }
49 impl<V:TyVisitor + MovePtr> MovePtrAdaptor<V> {
51 pub fn bump(&mut self, sz: uint) {
52 self.inner.move_ptr(|p| ((p as uint) + sz) as *u8)
56 pub fn align(&mut self, a: uint) {
57 self.inner.move_ptr(|p| align(p as uint, a) as *u8)
61 pub fn align_to<T>(&mut self) {
62 self.align(mem::min_align_of::<T>());
66 pub fn bump_past<T>(&mut self) {
67 self.bump(mem::size_of::<T>());
70 pub fn unwrap(self) -> V { self.inner }
73 /// Abstract type-directed pointer-movement using the MovePtr trait
74 impl<V:TyVisitor + MovePtr> TyVisitor for MovePtrAdaptor<V> {
75 fn visit_bot(&mut self) -> bool {
76 self.align_to::<()>();
77 if ! self.inner.visit_bot() { return false; }
78 self.bump_past::<()>();
82 fn visit_nil(&mut self) -> bool {
83 self.align_to::<()>();
84 if ! self.inner.visit_nil() { return false; }
85 self.bump_past::<()>();
89 fn visit_bool(&mut self) -> bool {
90 self.align_to::<bool>();
91 if ! self.inner.visit_bool() { return false; }
92 self.bump_past::<bool>();
96 fn visit_int(&mut self) -> bool {
97 self.align_to::<int>();
98 if ! self.inner.visit_int() { return false; }
99 self.bump_past::<int>();
103 fn visit_i8(&mut self) -> bool {
104 self.align_to::<i8>();
105 if ! self.inner.visit_i8() { return false; }
106 self.bump_past::<i8>();
110 fn visit_i16(&mut self) -> bool {
111 self.align_to::<i16>();
112 if ! self.inner.visit_i16() { return false; }
113 self.bump_past::<i16>();
117 fn visit_i32(&mut self) -> bool {
118 self.align_to::<i32>();
119 if ! self.inner.visit_i32() { return false; }
120 self.bump_past::<i32>();
124 fn visit_i64(&mut self) -> bool {
125 self.align_to::<i64>();
126 if ! self.inner.visit_i64() { return false; }
127 self.bump_past::<i64>();
131 fn visit_uint(&mut self) -> bool {
132 self.align_to::<uint>();
133 if ! self.inner.visit_uint() { return false; }
134 self.bump_past::<uint>();
138 fn visit_u8(&mut self) -> bool {
139 self.align_to::<u8>();
140 if ! self.inner.visit_u8() { return false; }
141 self.bump_past::<u8>();
145 fn visit_u16(&mut self) -> bool {
146 self.align_to::<u16>();
147 if ! self.inner.visit_u16() { return false; }
148 self.bump_past::<u16>();
152 fn visit_u32(&mut self) -> bool {
153 self.align_to::<u32>();
154 if ! self.inner.visit_u32() { return false; }
155 self.bump_past::<u32>();
159 fn visit_u64(&mut self) -> bool {
160 self.align_to::<u64>();
161 if ! self.inner.visit_u64() { return false; }
162 self.bump_past::<u64>();
166 fn visit_f32(&mut self) -> bool {
167 self.align_to::<f32>();
168 if ! self.inner.visit_f32() { return false; }
169 self.bump_past::<f32>();
173 fn visit_f64(&mut self) -> bool {
174 self.align_to::<f64>();
175 if ! self.inner.visit_f64() { return false; }
176 self.bump_past::<f64>();
180 fn visit_char(&mut self) -> bool {
181 self.align_to::<char>();
182 if ! self.inner.visit_char() { return false; }
183 self.bump_past::<char>();
187 fn visit_estr_box(&mut self) -> bool {
191 fn visit_estr_uniq(&mut self) -> bool {
192 self.align_to::<~str>();
193 if ! self.inner.visit_estr_uniq() { return false; }
194 self.bump_past::<~str>();
198 fn visit_estr_slice(&mut self) -> bool {
199 self.align_to::<&'static str>();
200 if ! self.inner.visit_estr_slice() { return false; }
201 self.bump_past::<&'static str>();
205 fn visit_estr_fixed(&mut self, n: uint,
207 align: uint) -> bool {
209 if ! self.inner.visit_estr_fixed(n, sz, align) { return false; }
214 fn visit_box(&mut self, mtbl: uint, inner: *TyDesc) -> bool {
215 self.align_to::<@u8>();
216 if ! self.inner.visit_box(mtbl, inner) { return false; }
217 self.bump_past::<@u8>();
221 fn visit_uniq(&mut self, mtbl: uint, inner: *TyDesc) -> bool {
222 self.align_to::<~u8>();
223 if ! self.inner.visit_uniq(mtbl, inner) { return false; }
224 self.bump_past::<~u8>();
228 fn visit_ptr(&mut self, mtbl: uint, inner: *TyDesc) -> bool {
229 self.align_to::<*u8>();
230 if ! self.inner.visit_ptr(mtbl, inner) { return false; }
231 self.bump_past::<*u8>();
235 fn visit_rptr(&mut self, mtbl: uint, inner: *TyDesc) -> bool {
236 self.align_to::<&'static u8>();
237 if ! self.inner.visit_rptr(mtbl, inner) { return false; }
238 self.bump_past::<&'static u8>();
242 fn visit_unboxed_vec(&mut self, mtbl: uint, inner: *TyDesc) -> bool {
243 self.align_to::<raw::Vec<()>>();
244 if ! self.inner.visit_vec(mtbl, inner) { return false; }
248 fn visit_vec(&mut self, mtbl: uint, inner: *TyDesc) -> bool {
249 self.align_to::<~[u8]>();
250 if ! self.inner.visit_vec(mtbl, inner) { return false; }
251 self.bump_past::<~[u8]>();
255 fn visit_evec_box(&mut self, _mtbl: uint, _inner: *TyDesc) -> bool {
259 fn visit_evec_uniq(&mut self, mtbl: uint, inner: *TyDesc) -> bool {
260 self.align_to::<~[u8]>();
261 if ! self.inner.visit_evec_uniq(mtbl, inner) { return false; }
262 self.bump_past::<~[u8]>();
266 fn visit_evec_slice(&mut self, mtbl: uint, inner: *TyDesc) -> bool {
267 self.align_to::<&'static [u8]>();
268 if ! self.inner.visit_evec_slice(mtbl, inner) { return false; }
269 self.bump_past::<&'static [u8]>();
273 fn visit_evec_fixed(&mut self, n: uint, sz: uint, align: uint,
274 mtbl: uint, inner: *TyDesc) -> bool {
276 if ! self.inner.visit_evec_fixed(n, sz, align, mtbl, inner) {
283 fn visit_enter_rec(&mut self, n_fields: uint, sz: uint, align: uint) -> bool {
285 if ! self.inner.visit_enter_rec(n_fields, sz, align) { return false; }
289 fn visit_rec_field(&mut self, i: uint, name: &str,
290 mtbl: uint, inner: *TyDesc) -> bool {
291 unsafe { self.align((*inner).align); }
292 if ! self.inner.visit_rec_field(i, name, mtbl, inner) {
295 unsafe { self.bump((*inner).size); }
299 fn visit_leave_rec(&mut self, n_fields: uint, sz: uint, align: uint) -> bool {
300 if ! self.inner.visit_leave_rec(n_fields, sz, align) { return false; }
304 fn visit_enter_class(&mut self, name: &str, named_fields: bool, n_fields: uint, sz: uint,
305 align: uint) -> bool {
307 if ! self.inner.visit_enter_class(name, named_fields, n_fields, sz, align) {
313 fn visit_class_field(&mut self, i: uint, name: &str, named: bool, mtbl: uint,
314 inner: *TyDesc) -> bool {
315 unsafe { self.align((*inner).align); }
316 if ! self.inner.visit_class_field(i, name, named, mtbl, inner) {
319 unsafe { self.bump((*inner).size); }
323 fn visit_leave_class(&mut self, name: &str, named_fields: bool, n_fields: uint, sz: uint,
324 align: uint) -> bool {
325 if ! self.inner.visit_leave_class(name, named_fields, n_fields, sz, align) {
331 fn visit_enter_tup(&mut self, n_fields: uint, sz: uint, align: uint) -> bool {
333 if ! self.inner.visit_enter_tup(n_fields, sz, align) { return false; }
337 fn visit_tup_field(&mut self, i: uint, inner: *TyDesc) -> bool {
338 unsafe { self.align((*inner).align); }
339 if ! self.inner.visit_tup_field(i, inner) { return false; }
340 unsafe { self.bump((*inner).size); }
344 fn visit_leave_tup(&mut self, n_fields: uint, sz: uint, align: uint) -> bool {
345 if ! self.inner.visit_leave_tup(n_fields, sz, align) { return false; }
349 fn visit_enter_fn(&mut self, purity: uint, proto: uint,
350 n_inputs: uint, retstyle: uint) -> bool {
351 if ! self.inner.visit_enter_fn(purity, proto, n_inputs, retstyle) {
357 fn visit_fn_input(&mut self, i: uint, mode: uint, inner: *TyDesc) -> bool {
358 if ! self.inner.visit_fn_input(i, mode, inner) { return false; }
362 fn visit_fn_output(&mut self, retstyle: uint, variadic: bool, inner: *TyDesc) -> bool {
363 if ! self.inner.visit_fn_output(retstyle, variadic, inner) { return false; }
367 fn visit_leave_fn(&mut self, purity: uint, proto: uint,
368 n_inputs: uint, retstyle: uint) -> bool {
369 if ! self.inner.visit_leave_fn(purity, proto, n_inputs, retstyle) {
375 fn visit_enter_enum(&mut self, n_variants: uint,
376 get_disr: extern unsafe fn(ptr: *Opaque) -> Disr,
377 sz: uint, align: uint)
380 if ! self.inner.visit_enter_enum(n_variants, get_disr, sz, align) {
386 fn visit_enter_enum_variant(&mut self, variant: uint,
389 name: &str) -> bool {
390 if ! self.inner.visit_enter_enum_variant(variant, disr_val,
397 fn visit_enum_variant_field(&mut self, i: uint, offset: uint, inner: *TyDesc) -> bool {
398 self.inner.push_ptr();
400 if ! self.inner.visit_enum_variant_field(i, offset, inner) { return false; }
401 self.inner.pop_ptr();
405 fn visit_leave_enum_variant(&mut self, variant: uint,
408 name: &str) -> bool {
409 if ! self.inner.visit_leave_enum_variant(variant, disr_val,
416 fn visit_leave_enum(&mut self, n_variants: uint,
417 get_disr: extern unsafe fn(ptr: *Opaque) -> Disr,
418 sz: uint, align: uint) -> bool {
419 if ! self.inner.visit_leave_enum(n_variants, get_disr, sz, align) {
426 fn visit_trait(&mut self, name: &str) -> bool {
427 self.align_to::<~TyVisitor>();
428 if ! self.inner.visit_trait(name) { return false; }
429 self.bump_past::<~TyVisitor>();
433 fn visit_param(&mut self, i: uint) -> bool {
434 if ! self.inner.visit_param(i) { return false; }
438 fn visit_self(&mut self) -> bool {
439 self.align_to::<&'static u8>();
440 if ! self.inner.visit_self() { return false; }
441 self.align_to::<&'static u8>();