Repository navigation
Expand file tree
/
Copy pathluaclass.c
More file actions
366 lines (320 loc) · 10.9 KB
/
Copy pathluaclass.c
File metadata and controls
366 lines (320 loc) · 10.9 KB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
/*
* luaclass.c - useful functions for handling Lua classes
*
* Copyright © 2009 Julien Danjou <julien@danjou.info>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*
*/
#include "common/luaclass.h"
#include "common/luaobject.h"
struct lua_class_property
{
/** ID matching the property */
awesome_token_t id;
/** Callback function called when the property is found in object creation. */
lua_class_propfunc_t new;
/** Callback function called when the property is found in object __index. */
lua_class_propfunc_t index;
/** Callback function called when the property is found in object __newindex. */
lua_class_propfunc_t newindex;
};
DO_ARRAY(lua_class_t *, lua_class, DO_NOTHING)
static lua_class_array_t luaA_classes;
/** Convert a object to a udata if possible.
* \param L The Lua VM state.
* \param ud The index.
* \param class The wanted class.
* \return A pointer to the object, NULL otherwise.
*/
void *
luaA_toudata(lua_State *L, int ud, lua_class_t *class)
{
void *p = lua_touserdata(L, ud);
if(p) /* value is a userdata? */
if(lua_getmetatable(L, ud)) /* does it have a metatable? */
{
lua_pushlightuserdata(L, class);
lua_rawget(L, LUA_REGISTRYINDEX);
if(!lua_rawequal(L, -1, -2)) /* does it have the correct mt? */
p = NULL;
lua_pop(L, 2); /* remove both metatables */
}
return p;
}
/** Check for a udata class.
* \param L The Lua VM state.
* \param ud The object index on the stack.
* \param class The wanted class.
*/
void *
luaA_checkudata(lua_State *L, int ud, lua_class_t *class)
{
void *p = luaA_toudata(L, ud, class);
if(!p)
luaL_typerror(L, ud, class->name);
return p;
}
/** Get an object lua_class.
* \param L The Lua VM state.
* \param idx The index of the object on the stack.
*/
lua_class_t *
luaA_class_get(lua_State *L, int idx)
{
int type = lua_type(L, idx);
if(type == LUA_TUSERDATA)
foreach(class, luaA_classes)
if(luaA_toudata(L, idx, *class))
return *class;
return NULL;
}
/** Enhanced version of lua_typename that recognizes setup Lua classes.
* \param L The Lua VM state.
* \param idx The index of the object on the stack.
*/
const char *
luaA_typename(lua_State *L, int idx)
{
int type = lua_type(L, idx);
if(type == LUA_TUSERDATA)
{
lua_class_t *lua_class = luaA_class_get(L, idx);
if(lua_class)
return lua_class->name;
}
return lua_typename(L, type);
}
void
luaA_openlib(lua_State *L, const char *name,
const struct luaL_reg methods[],
const struct luaL_reg meta[])
{
luaL_newmetatable(L, name); /* 1 */
lua_pushvalue(L, -1); /* dup metatable 2 */
lua_setfield(L, -2, "__index"); /* metatable.__index = metatable 1 */
luaL_register(L, NULL, meta); /* 1 */
luaL_register(L, name, methods); /* 2 */
lua_pushvalue(L, -1); /* dup self as metatable 3 */
lua_setmetatable(L, -2); /* set self as metatable 2 */
lua_pop(L, 2);
}
static int
lua_class_property_cmp(const void *a, const void *b)
{
const lua_class_property_t *x = a, *y = b;
return x->id > y->id ? 1 : (x->id < y->id ? -1 : 0);
}
BARRAY_FUNCS(lua_class_property_t, lua_class_property, DO_NOTHING, lua_class_property_cmp)
void
luaA_class_add_property(lua_class_t *lua_class,
awesome_token_t token,
lua_class_propfunc_t cb_new,
lua_class_propfunc_t cb_index,
lua_class_propfunc_t cb_newindex)
{
lua_class_property_array_insert(&lua_class->properties, (lua_class_property_t)
{
.id = token,
.new = cb_new,
.index = cb_index,
.newindex = cb_newindex
});
}
void
luaA_class_setup(lua_State *L, lua_class_t *class,
const char *name,
lua_class_allocator_t allocator,
lua_class_propfunc_t index_miss_property,
lua_class_propfunc_t newindex_miss_property,
const struct luaL_reg methods[],
const struct luaL_reg meta[])
{
/* Create the metatable */
lua_newtable(L);
/* Register it with class pointer as key in the registry */
lua_pushlightuserdata(L, class);
/* Duplicate the metatable */
lua_pushvalue(L, -2);
lua_rawset(L, LUA_REGISTRYINDEX);
lua_pushvalue(L, -1); /* dup metatable 2 */
lua_setfield(L, -2, "__index"); /* metatable.__index = metatable 1 */
luaL_register(L, NULL, meta); /* 1 */
luaL_register(L, name, methods); /* 2 */
lua_pushvalue(L, -1); /* dup self as metatable 3 */
lua_setmetatable(L, -2); /* set self as metatable 2 */
lua_pop(L, 2);
class->allocator = allocator;
class->name = name;
class->index_miss_property = index_miss_property;
class->newindex_miss_property = newindex_miss_property;
lua_class_array_append(&luaA_classes, class);
}
void
luaA_class_add_signal(lua_State *L, lua_class_t *lua_class,
const char *name, int ud)
{
luaA_checkfunction(L, ud);
signal_add(&lua_class->signals, name, luaA_object_ref(L, ud));
}
void
luaA_class_remove_signal(lua_State *L, lua_class_t *lua_class,
const char *name, int ud)
{
luaA_checkfunction(L, ud);
void *ref = (void *) lua_topointer(L, ud);
signal_remove(&lua_class->signals, name, ref);
luaA_object_unref(L, (void *) ref);
lua_remove(L, ud);
}
void
luaA_class_emit_signal(lua_State *L, lua_class_t *lua_class,
const char *name, int nargs)
{
signal_object_emit(L, &lua_class->signals, name, nargs);
}
/** Try to use the metatable of an object.
* \param L The Lua VM state.
* \param idxobj The index of the object.
* \param idxfield The index of the field (attribute) to get.
* \return The number of element pushed on stack.
*/
int
luaA_usemetatable(lua_State *L, int idxobj, int idxfield)
{
/* Get metatable of the object. */
lua_getmetatable(L, idxobj);
/* Get the field */
lua_pushvalue(L, idxfield);
lua_rawget(L, -2);
/* Do we have a field like that? */
if(!lua_isnil(L, -1))
{
/* Yes, so return it! */
lua_remove(L, -2);
return 1;
}
/* No, so remove everything. */
lua_pop(L, 2);
return 0;
}
static lua_class_property_t *
lua_class_property_array_getbyid(lua_class_property_array_t *arr,
awesome_token_t id)
{
lua_class_property_t lookup_prop = { .id = id };
return lua_class_property_array_lookup(arr, &lookup_prop);
}
/** Get a property of a object.
* \param L The Lua VM state.
* \param lua_class The Lua class.
* \param fieldidx The index of the field name.
* \return The object property if found, NULL otherwise.
*/
static lua_class_property_t *
luaA_class_property_get(lua_State *L, lua_class_t *lua_class, int fieldidx)
{
/* Lookup the property using token */
size_t len;
const char *attr = luaL_checklstring(L, fieldidx, &len);
awesome_token_t token = a_tokenize(attr, len);
return lua_class_property_array_getbyid(&lua_class->properties, token);
}
/** Generic index meta function for objects.
* \param L The Lua VM state.
* \return The number of elements pushed on stack.
*/
int
luaA_class_index(lua_State *L)
{
/* Try to use metatable first. */
if(luaA_usemetatable(L, 1, 2))
return 1;
lua_class_t *class = luaA_class_get(L, 1);
lua_class_property_t *prop = luaA_class_property_get(L, class, 2);
/* Property does exist and has an index callback */
if(prop)
{
if(prop->index)
return prop->index(L, luaA_checkudata(L, 1, class));
}
else
{
if(class->index_miss_property)
return class->index_miss_property(L, luaA_checkudata(L, 1, class));
}
return 0;
}
/** Generic newindex meta function for objects.
* \param L The Lua VM state.
* \return The number of elements pushed on stack.
*/
int
luaA_class_newindex(lua_State *L)
{
/* Try to use metatable first. */
if(luaA_usemetatable(L, 1, 2))
return 1;
lua_class_t *class = luaA_class_get(L, 1);
lua_class_property_t *prop = luaA_class_property_get(L, class, 2);
/* Property does exist and has a newindex callback */
if(prop)
{
if(prop->newindex)
return prop->newindex(L, luaA_checkudata(L, 1, class));
}
else
{
if(class->newindex_miss_property)
return class->newindex_miss_property(L, luaA_checkudata(L, 1, class));
}
return 0;
}
/** Generic constructor function for objects.
* \param L The Lua VM state.
* \return The number of elements pushed on stack.
*/
int
luaA_class_new(lua_State *L, lua_class_t *lua_class)
{
/* Check we have a table that should contains some properties */
luaA_checktable(L, 2);
/* Create a new object */
void *object = lua_class->allocator(L);
/* Push the first key before iterating */
lua_pushnil(L);
/* Iterate over the property keys */
while(lua_next(L, 2))
{
/* Check that the key is a string.
* We cannot call tostring blindly or Lua will convert a key that is a
* number TO A STRING, confusing lua_next() */
if(lua_isstring(L, -2))
{
/* Lookup the property using token */
size_t len;
const char *attr = lua_tolstring(L, -2, &len);
lua_class_property_t *prop =
lua_class_property_array_getbyid(&lua_class->properties,
a_tokenize(attr, len));
if(prop && prop->new)
prop->new(L, object);
}
/* Remove value */
lua_pop(L, 1);
}
return 1;
}
// vim: filetype=c:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:textwidth=80