1 /* go-type.h -- basic information for a Go type.
2
3 Copyright 2009 The Go Authors. All rights reserved.
4 Use of this source code is governed by a BSD-style
5 license that can be found in the LICENSE file. */
6
7 #ifndef LIBGO_GO_TYPE_H
8 #define LIBGO_GO_TYPE_H
9
10 #include <stddef.h>
11 #include <stdint.h>
12
13 #include "array.h"
14
15 struct String;
16
17 /* Many of the types in this file must match the data structures
18 generated by the compiler, and must also match the Go types which
19 appear in go/runtime/type.go and go/reflect/type.go. */
20
21 /* Type kinds. These are used to get the type descriptor to use for
22 the type itself, when using unsafe.Typeof or unsafe.Reflect. The
23 values here must match the values generated by the compiler (the
24 RUNTIME_TYPE_KIND_xxx values in gcc/go/types.h). These are macros
25 rather than an enum to make it easy to change values in the future
26 and hard to get confused about it.
27
28 These correspond to the kind values used by the gc compiler. */
29
30 #define GO_BOOL 1
31 #define GO_INT 2
32 #define GO_INT8 3
33 #define GO_INT16 4
34 #define GO_INT32 5
35 #define GO_INT64 6
36 #define GO_UINT 7
37 #define GO_UINT8 8
38 #define GO_UINT16 9
39 #define GO_UINT32 10
40 #define GO_UINT64 11
41 #define GO_UINTPTR 12
42 #define GO_FLOAT32 13
43 #define GO_FLOAT64 14
44 #define GO_COMPLEX64 15
45 #define GO_COMPLEX128 16
46 #define GO_ARRAY 17
47 #define GO_CHAN 18
48 #define GO_FUNC 19
49 #define GO_INTERFACE 20
50 #define GO_MAP 21
51 #define GO_PTR 22
52 #define GO_SLICE 23
53 #define GO_STRING 24
54 #define GO_STRUCT 25
55 #define GO_UNSAFE_POINTER 26
56
57 #define GO_NO_POINTERS (1 << 7)
58
59 #define GO_CODE_MASK 0x7f
60
61 /* For each Go type the compiler constructs one of these structures.
62 This is used for type reflectin, interfaces, maps, and reference
63 counting. */
64
65 struct __go_type_descriptor
66 {
67 /* The type code for this type, one of the type kind values above.
68 This is used by unsafe.Reflect and unsafe.Typeof to determine the
69 type descriptor to return for this type itself. It is also used
70 by reflect.toType when mapping to a reflect Type structure. */
71 unsigned char __code;
72
73 /* The alignment in bytes of a variable with this type. */
74 unsigned char __align;
75
76 /* The alignment in bytes of a struct field with this type. */
77 unsigned char __field_align;
78
79 /* The size in bytes of a value of this type. Note that all types
80 in Go have a fixed size. */
81 uintptr_t __size;
82
83 /* The type's hash code. */
84 uint32_t __hash;
85
86 /* This function takes a pointer to a value of this type, and the
87 size of this type, and returns a hash code. We pass the size
88 explicitly becaues it means that we can share a single instance
89 of this function for various different types. */
90 uintptr_t (*__hashfn) (const void *, uintptr_t);
91
92 /* This function takes two pointers to values of this type, and the
93 size of this type, and returns whether the values are equal. */
94 _Bool (*__equalfn) (const void *, const void *, uintptr_t);
95
96 /* A string describing this type. This is only used for
97 debugging. */
98 const struct String *__reflection;
99
100 /* A pointer to fields which are only used for some types. */
101 const struct __go_uncommon_type *__uncommon;
102
103 /* The descriptor for the type which is a pointer to this type.
104 This may be NULL. */
105 const struct __go_type_descriptor *__pointer_to_this;
106 };
107
108 /* The information we store for each method of a type. */
109
110 struct __go_method
111 {
112 /* The name of the method. */
113 const struct String *__name;
114
115 /* This is NULL for an exported method, or the name of the package
116 where it lives. */
117 const struct String *__pkg_path;
118
119 /* The type of the method, without the receiver. This will be a
120 function type. */
121 const struct __go_type_descriptor *__mtype;
122
123 /* The type of the method, with the receiver. This will be a
124 function type. */
125 const struct __go_type_descriptor *__type;
126
127 /* A pointer to the code which implements the method. This is
128 really a function pointer. */
129 const void *__function;
130 };
131
132 /* Additional information that we keep for named types and for types
133 with methods. */
134
135 struct __go_uncommon_type
136 {
137 /* The name of the type. */
138 const struct String *__name;
139
140 /* The type's package. This is NULL for builtin types. */
141 const struct String *__pkg_path;
142
143 /* The type's methods. This is an array of struct __go_method. */
144 struct __go_open_array __methods;
145 };
146
147 /* The type descriptor for a fixed array type. */
148
149 struct __go_array_type
150 {
151 /* Starts like all type descriptors. */
152 struct __go_type_descriptor __common;
153
154 /* The element type. */
155 struct __go_type_descriptor *__element_type;
156
157 /* The type of a slice of the same element type. */
158 struct __go_type_descriptor *__slice_type;
159
160 /* The length of the array. */
161 uintptr_t __len;
162 };
163
164 /* The type descriptor for a slice. */
165
166 struct __go_slice_type
167 {
168 /* Starts like all other type descriptors. */
169 struct __go_type_descriptor __common;
170
171 /* The element type. */
172 struct __go_type_descriptor *__element_type;
173 };
174
175 /* The direction of a channel. */
176 #define CHANNEL_RECV_DIR 1
177 #define CHANNEL_SEND_DIR 2
178 #define CHANNEL_BOTH_DIR (CHANNEL_RECV_DIR | CHANNEL_SEND_DIR)
179
180 /* The type descriptor for a channel. */
181
182 struct __go_channel_type
183 {
184 /* Starts like all other type descriptors. */
185 struct __go_type_descriptor __common;
186
187 /* The element type. */
188 const struct __go_type_descriptor *__element_type;
189
190 /* The direction. */
191 uintptr_t __dir;
192 };
193
194 /* The type descriptor for a function. */
195
196 struct __go_func_type
197 {
198 /* Starts like all other type descriptors. */
199 struct __go_type_descriptor __common;
200
201 /* Whether this is a varargs function. If this is true, there will
202 be at least one parameter. For "..." the last parameter type is
203 "interface{}". For "... T" the last parameter type is "[]T". */
204 _Bool __dotdotdot;
205
206 /* The input parameter types. This is an array of pointers to
207 struct __go_type_descriptor. */
208 struct __go_open_array __in;
209
210 /* The output parameter types. This is an array of pointers to
211 struct __go_type_descriptor. */
212 struct __go_open_array __out;
213 };
214
215 /* A method on an interface type. */
216
217 struct __go_interface_method
218 {
219 /* The name of the method. */
220 const struct String *__name;
221
222 /* This is NULL for an exported method, or the name of the package
223 where it lives. */
224 const struct String *__pkg_path;
225
226 /* The real type of the method. */
227 struct __go_type_descriptor *__type;
228 };
229
230 /* An interface type. */
231
232 struct __go_interface_type
233 {
234 /* Starts like all other type descriptors. */
235 struct __go_type_descriptor __common;
236
237 /* Array of __go_interface_method . The methods are sorted in the
238 same order that they appear in the definition of the
239 interface. */
240 struct __go_open_array __methods;
241 };
242
243 /* A map type. */
244
245 struct __go_map_type
246 {
247 /* Starts like all other type descriptors. */
248 struct __go_type_descriptor __common;
249
250 /* The map key type. */
251 const struct __go_type_descriptor *__key_type;
252
253 /* The map value type. */
254 const struct __go_type_descriptor *__val_type;
255 };
256
257 /* A pointer type. */
258
259 struct __go_ptr_type
260 {
261 /* Starts like all other type descriptors. */
262 struct __go_type_descriptor __common;
263
264 /* The type to which this points. */
265 const struct __go_type_descriptor *__element_type;
266 };
267
268 /* A field in a structure. */
269
270 struct __go_struct_field
271 {
272 /* The name of the field--NULL for an anonymous field. */
273 const struct String *__name;
274
275 /* This is NULL for an exported method, or the name of the package
276 where it lives. */
277 const struct String *__pkg_path;
278
279 /* The type of the field. */
280 const struct __go_type_descriptor *__type;
281
282 /* The field tag, or NULL. */
283 const struct String *__tag;
284
285 /* The offset of the field in the struct. */
286 uintptr_t __offset;
287 };
288
289 /* A struct type. */
290
291 struct __go_struct_type
292 {
293 /* Starts like all other type descriptors. */
294 struct __go_type_descriptor __common;
295
296 /* An array of struct __go_struct_field. */
297 struct __go_open_array __fields;
298 };
299
300 /* If an empty interface has these bits set in its type pointer, it
301 was copied from a reflect.Value and is not a valid empty
302 interface. */
303
304 enum
305 {
306 reflectFlags = 3,
307 };
308
309 /* Whether a type descriptor is a pointer. */
310
311 static inline _Bool
__go_is_pointer_type(const struct __go_type_descriptor * td)312 __go_is_pointer_type (const struct __go_type_descriptor *td)
313 {
314 return td->__code == GO_PTR || td->__code == GO_UNSAFE_POINTER;
315 }
316
317 extern _Bool
318 __go_type_descriptors_equal(const struct __go_type_descriptor*,
319 const struct __go_type_descriptor*);
320
321 extern uintptr_t __go_type_hash_identity (const void *, uintptr_t);
322 extern _Bool __go_type_equal_identity (const void *, const void *, uintptr_t);
323 extern uintptr_t __go_type_hash_string (const void *, uintptr_t);
324 extern _Bool __go_type_equal_string (const void *, const void *, uintptr_t);
325 extern uintptr_t __go_type_hash_float (const void *, uintptr_t);
326 extern _Bool __go_type_equal_float (const void *, const void *, uintptr_t);
327 extern uintptr_t __go_type_hash_complex (const void *, uintptr_t);
328 extern _Bool __go_type_equal_complex (const void *, const void *, uintptr_t);
329 extern uintptr_t __go_type_hash_interface (const void *, uintptr_t);
330 extern _Bool __go_type_equal_interface (const void *, const void *, uintptr_t);
331 extern uintptr_t __go_type_hash_error (const void *, uintptr_t);
332 extern _Bool __go_type_equal_error (const void *, const void *, uintptr_t);
333
334 #endif /* !defined(LIBGO_GO_TYPE_H) */
335