-
Notifications
You must be signed in to change notification settings - Fork 1
/
moon.c
1239 lines (1130 loc) · 37.2 KB
/
moon.c
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
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
/* Copyright 2013-2020 Philipp Janda <siffiejoe@gmx.net>
*
* You may do anything with this work that copyright law would normally
* restrict, so long as you retain the above notice(s) and this license
* in all redistributed copies and derived works. There is no warranty.
*/
#include <stddef.h>
#include <string.h>
#include <stdio.h>
#include <stdarg.h>
#include <limits.h>
#include <ctype.h>
#include "moon.h"
/* don't compile it again if it's already included via moon.h */
#ifndef MOON_C_
#define MOON_C_
#if LUA_VERSION_NUM < 502
MOON_API int moon_absindex( lua_State* L, int i ) {
if( i < 0 && i > LUA_REGISTRYINDEX )
i += lua_gettop( L ) + 1;
return i;
}
#endif
/* struct that is part of some moon objects (those created via
* `moon_newfield`) and contains a function pointer and a data pointer
* that can be used to check whether the object is still valid. The
* check is done automatically in `moon_{check,test}object`, and is
* primarily needed to safely support tagged unions. */
typedef struct moon_object_vcheck_ {
int (*check)( void* );
void* tagp;
struct moon_object_vcheck_* next; /* linked list */
} moon_object_vcheck_;
/* For keeping memory consumption as low as possible multiple C
* values might be stored side-by-side in the same memory block, and
* we have to figure out the alignment to use for those values. */
typedef union {
lua_Number n;
double d;
lua_Integer i;
long l;
size_t s;
void* p;
void (*fp)( void );
} moon_object_alignment_u_;
/* Newer versions of C and C++ have a way to figure out alignment
* built into the language, and we use those if available. There's
* also a fallback implementation for older versions. */
#ifndef MOON_ALIGNOF_
# if defined( __cplusplus ) && __cplusplus >= 201103L
/* alignof is an operator in newer C++ versions */
# define MOON_ALIGNOF_( _t ) alignof( _t )
# elif defined( __STDC_VERSION__ ) && __STDC_VERSION__ >= 201112L
/* newer C versions have it in stdalign.h */
# include <stdalign.h>
# define MOON_ALIGNOF_( _t ) alignof( _t )
# elif defined( __cplusplus )
/* Same as below, but MSVC++ has problems with that code, so we use a
* template instead of a type-as-expression. */
template< typename T >
struct moon_alignof_struct_ {
char _1;
T _2;
};
# define MOON_ALIGNOF_( _t ) \
(offsetof( moon_alignof_struct_< _t >, _2 ) > sizeof( _t ) \
? sizeof( _t ) \
: offsetof( moon_alignof_struct_< _t >, _2 ))
# else
/* Calculate the alignment ourselves. This may give smaller values
* than using `sizeof( _t )` which is also a portable solution. */
# define MOON_ALIGNOF_( _t ) \
(offsetof( struct { char _1; _t _2; }, _2 ) > sizeof( _t ) \
? sizeof( _t ) \
: offsetof( struct { char _1; _t _2; }, _2 ))
# endif
#endif
#define MOON_OBJ_ALIGNMENT_ MOON_ALIGNOF_( moon_object_alignment_u_ )
#define MOON_PTR_ALIGNMENT_ MOON_ALIGNOF_( void* )
#define MOON_GCF_ALIGNMENT_ MOON_ALIGNOF_( moon_object_destructor )
#define MOON_VCK_ALIGNMENT_ MOON_ALIGNOF_( moon_object_vcheck_ )
#define MOON_ROUNDTO_( _s, _a ) ((((_s)+(_a)-1)/(_a))*(_a))
#define MOON_PTR_( _p, _o ) ((void*)(((char*)(_p))+(_o)))
/* Raise properly formatted argument error messages. */
static int moon_type_error_( lua_State* L, int i, char const* t1,
char const* t2 ) {
char const* msg = lua_pushfstring( L, "%s expected, got %s", t1, t2 );
return luaL_argerror( L, i, msg );
}
static int moon_type_error_invalid_( lua_State* L, int i,
char const* tname ) {
char const* msg = lua_pushfstring( L, "invalid '%s' object", tname );
return luaL_argerror( L, i, msg );
}
static int moon_type_error_version_( lua_State* L, int i ) {
char const* msg = lua_pushfstring( L, "not a moon %d.%d object",
MOON_VERSION_MAJOR,
MOON_VERSION_MINOR );
return luaL_argerror( L, i, msg );
}
static int moon_is_property( char const* name ) {
return name[ 0 ] == '.';
}
static int moon_is_meta( char const* name ) {
return name[ 0 ] == '_' && name[ 1 ] == '_';
}
static int moon_is_method( char const* name ) {
return !moon_is_meta( name ) && !moon_is_property( name );
}
/* Default implementation of a __tostring metamethod for moon objects
* which displays the type name and memory address. */
MOON_LLINKAGE_BEGIN
static int moon_object_default_tostring_( lua_State* L ) {
void* ptr = lua_touserdata( L, 1 );
char const* name = lua_tostring( L, lua_upvalueindex( 1 ) );
char const* basename = strrchr( name, '.' );
if( basename != NULL )
name = basename+1;
lua_pushfstring( L, "[%s]: %p", name, ptr );
return 1;
}
MOON_LLINKAGE_END
/* Run the destructor and mark the object as invalid/destroyed. */
static void moon_object_run_destructor_( moon_object_header* h ) {
if( h->cleanup_offset > 0 && (h->flags & MOON_OBJECT_IS_VALID) ) {
void* p = MOON_PTR_( h, h->object_offset );
moon_object_destructor* gc = NULL;
gc = (moon_object_destructor*)MOON_PTR_( h, h->cleanup_offset );
if( h->flags & MOON_OBJECT_IS_POINTER )
p = *((void**)p);
if( *gc != 0 && p != NULL )
(*gc)( p );
}
h->flags &= ~MOON_OBJECT_IS_VALID;
}
/* Common __gc metamethod for all moon objects. The actual finalizer
* function is stored in the userdata to support different lifetimes.
*/
MOON_LLINKAGE_BEGIN
static int moon_object_default_gc_( lua_State* L ) {
moon_object_header* h = (moon_object_header*)lua_touserdata( L, 1 );
moon_object_run_destructor_( h );
return 0;
}
MOON_LLINKAGE_END
static int moon_index_dispatch_methods_( lua_State* L ) {
if( lua_type( L, lua_upvalueindex( 1 ) ) == LUA_TTABLE ) {
lua_pushvalue( L, 2 ); /* duplicate key */
lua_rawget( L, lua_upvalueindex( 1 ) );
if( !lua_isnil( L, -1 ) )
return 1;
lua_pop( L, 1 );
}
return 0;
}
static int moon_index_dispatch_properties_( lua_State* L ) {
if( lua_type( L, lua_upvalueindex( 2 ) ) == LUA_TTABLE ) {
lua_pushvalue( L, 2 ); /* duplicate key */
lua_rawget( L, lua_upvalueindex( 2 ) );
if( !lua_isnil( L, -1 ) ) {
lua_pushvalue( L, 1 );
lua_call( L, 1, 1 );
return 1;
}
lua_pop( L, 1 );
}
return 0;
}
static int moon_index_dispatch_function_( lua_State* L ) {
if( lua_type( L, lua_upvalueindex( 3 ) ) == LUA_TFUNCTION ) {
lua_pushvalue( L, lua_upvalueindex( 3 ) );
lua_pushvalue( L, 1 );
lua_pushvalue( L, 2 );
lua_call( L, 2, 1 );
return 1;
}
return 0;
}
static int moon_newindex_dispatch_properties_( lua_State* L ) {
if( lua_type( L, lua_upvalueindex( 1 ) ) == LUA_TTABLE ) {
lua_pushvalue( L, 2 ); /* duplicate key */
lua_rawget( L, lua_upvalueindex( 1 ) );
if( lua_isfunction( L, -1 ) ) {
lua_pushvalue( L, 1 );
lua_pushvalue( L, 2 );
lua_pushvalue( L, 3 );
lua_call( L, 3, 0 );
return 1;
}
lua_pop( L, 1 );
}
return 0;
}
static int moon_newindex_dispatch_function_( lua_State* L ) {
if( lua_type( L, lua_upvalueindex( 2 ) ) == LUA_TFUNCTION ) {
lua_pushvalue( L, lua_upvalueindex( 2 ) );
lua_pushvalue( L, 1 );
lua_pushvalue( L, 2 );
lua_pushvalue( L, 3 );
lua_call( L, 3, 0 );
return 1;
}
return 0;
}
/* Check the methods and properties tables for a given key and then
* (if unsuccessful) call the registered C function for looking up
* properties. */
MOON_LLINKAGE_BEGIN
static int moon_index_dispatch_( lua_State* L ) {
if( !moon_index_dispatch_methods_( L ) &&
!moon_index_dispatch_properties_( L ) &&
!moon_index_dispatch_function_( L ) )
lua_pushnil( L );
return 1;
}
static int moon_newindex_dispatch_( lua_State* L ) {
if( !moon_newindex_dispatch_properties_( L ) &&
!moon_newindex_dispatch_function_( L ) )
luaL_error( L, "attempt to set invalid field" );
return 0;
}
MOON_LLINKAGE_END
static lua_CFunction moon_getf_( lua_State* L, char const* name,
lua_CFunction def ) {
lua_CFunction f = 0;
lua_pushliteral( L, "__moon" );
lua_rawget( L, LUA_REGISTRYINDEX );
if( lua_type( L, -1 ) != LUA_TTABLE ) {
lua_pop( L, 1 );
lua_newtable( L );
lua_pushliteral( L, "__moon" );
lua_pushvalue( L, -2 );
lua_rawset( L, LUA_REGISTRYINDEX );
}
lua_getfield( L, -1, name );
f = lua_tocfunction( L, -1 );
lua_pop( L, 1 );
if( !f ) {
f = def;
lua_pushcfunction( L, def );
lua_setfield( L, -2, name );
}
lua_pop( L, 1 );
return f;
}
static void moon_pushreg_( lua_State* L, luaL_Reg const funcs[],
int (*predicate)( char const* ),
int nups, int firstupvalue, int skip ) {
if( funcs != NULL ) {
lua_newtable( L );
for( ; funcs->func; ++funcs ) {
if( predicate( funcs->name ) ) {
int i = 0;
for( i = 0; i < nups; ++i )
lua_pushvalue( L, firstupvalue + i );
lua_pushcclosure( L, funcs->func, nups );
lua_setfield( L, -2, funcs->name + skip );
}
}
} else
lua_pushnil( L );
}
static void moon_pushfunction_( lua_State* L, lua_CFunction func,
int nups, int firstupvalue ) {
if( func != 0 ) {
int i = 0;
for( i = 0; i < nups; ++i )
lua_pushvalue( L, firstupvalue + i );
lua_pushcclosure( L, func, nups );
} else
lua_pushnil( L );
}
/* Depending on the availability of a methods table and/or a C
* function for looking up properties this function creates an __index
* metamethod (function or table). */
static void moon_makeindex_( lua_State* L, luaL_Reg const methods[],
luaL_Reg const properties[],
lua_CFunction pindex, int nups ) {
int firstupvalue = lua_gettop( L ) + 1 - nups;
if( !properties && !pindex ) { /* methods only (maybe) */
moon_pushreg_( L, methods, moon_is_method, nups, firstupvalue, 0 );
if( nups > 0 ) {
lua_replace( L, firstupvalue );
lua_pop( L, nups-1 );
}
} else if( !methods && !properties ) { /* index function only */
lua_pushcclosure( L, pindex, nups );
} else {
lua_CFunction dispatch = moon_getf_( L, "index", moon_index_dispatch_ );
moon_pushreg_( L, methods, moon_is_method, nups, firstupvalue, 0 );
moon_pushreg_( L, properties, moon_is_property, nups, firstupvalue, 1 );
moon_pushfunction_( L, pindex, nups, firstupvalue );
lua_pushcclosure( L, dispatch, 3 );
if( nups > 0 ) {
lua_replace( L, firstupvalue );
lua_pop( L, nups-1 );
}
}
}
static void moon_makenewindex_( lua_State* L, luaL_Reg const properties[],
lua_CFunction pnewindex, int nups ) {
if( !properties && !pnewindex ) {
lua_pop( L, nups );
lua_pushnil( L );
} else if( !properties ) {
lua_pushcclosure( L, pnewindex, nups );
} else {
int firstupvalue = lua_gettop( L ) + 1 - nups;
lua_CFunction dispatch = moon_getf_( L, "newindex", moon_newindex_dispatch_ );
moon_pushreg_( L, properties, moon_is_property, nups, firstupvalue, 1 );
moon_pushfunction_( L, pnewindex, nups, firstupvalue );
lua_pushcclosure( L, dispatch, 2 );
if( nups > 0 ) {
lua_replace( L, firstupvalue );
lua_pop( L, nups-1 );
}
}
}
/* Type names used by the moon toolkit must not start with a double
* underscore, because they might be used as keys in the metatable. */
static void moon_check_tname_( lua_State* L, char const* tname ) {
if( tname == NULL || tname[ 0 ] == '_' )
luaL_error( L, "invalid type name: '%s'", tname ? tname : "NULL" );
}
MOON_API void moon_defobject( lua_State* L, char const* tname,
size_t sz, luaL_Reg const* methods,
int nups ) {
int has_methods = 0;
int has_properties = 0;
lua_CFunction index = 0;
lua_CFunction newindex = 0;
moon_check_tname_( L, tname );
luaL_checkstack( L, 2*nups+4, "moon_defobject" );
/* we don't use luaL_newmetatable to make sure that we never have a
* half-constructed metatable in the registry! */
luaL_getmetatable( L, tname );
if( !lua_isnil( L, -1 ) )
luaL_error( L, "type '%s' is already defined", tname );
lua_pop( L, 1 );
lua_newtable( L );
lua_pushstring( L, tname );
lua_pushcclosure( L, moon_object_default_tostring_, 1 );
lua_setfield( L, -2, "__tostring" );
if( methods != NULL ) {
luaL_Reg const* l = methods;
int i = 0;
for( ; l->func != NULL; ++l ) {
if( moon_is_meta( l->name ) ) {
int is_index = 0 == strcmp( l->name+2, "index" );
int is_newindex = 0 == strcmp( l->name+2, "newindex" );
if( !is_index && !is_newindex ) {
for( i = 0; i < nups; ++i )
lua_pushvalue( L, -nups-1 );
lua_pushcclosure( L, l->func, nups );
lua_setfield( L, -2, l->name );
} else if( is_index ) /* handle __index later */
index = l->func;
else /* handle __newindex later */
newindex = l->func;
} else if( moon_is_property( l->name ) ) {
has_properties = 1;
} else
has_methods = 1;
}
}
if( has_methods || has_properties || index ) {
int i = 0;
for( i = 0; i < nups; ++i )
lua_pushvalue( L, -nups-1 );
moon_makeindex_( L, has_methods ? methods : NULL,
has_properties ? methods : NULL, index, nups );
lua_setfield( L, -2, "__index" );
}
if( has_properties || newindex ) {
int i = 0;
for( i = 0; i < nups; ++i )
lua_pushvalue( L, -nups-1 );
moon_makenewindex_( L, methods, newindex, nups );
lua_setfield( L, -2, "__newindex" );
}
lua_pushboolean( L, 0 );
lua_setfield( L, -2, "__metatable" );
lua_pushstring( L, tname );
lua_setfield( L, -2, "__name" );
lua_pushcfunction( L, moon_object_default_gc_ );
lua_pushvalue( L, -1);
lua_setfield( L, -3, "__gc" );
lua_setfield( L, -2, "__close" );
lua_pushinteger( L, MOON_VERSION );
lua_setfield( L, -2, "__moon_version" );
lua_pushinteger( L, (lua_Integer)sz );
lua_setfield( L, -2, "__moon_size" );
lua_setfield( L, LUA_REGISTRYINDEX, tname );
lua_pop( L, nups );
}
/* Verify that the value at the stack top is the metatable for a moon
* object type. */
static void moon_check_metatable_( lua_State* L, char const* tname ) {
if( !lua_istable( L, -1 ) )
luaL_error( L, "no metatable for type '%s' defined", tname );
lua_getfield( L, -1, "__moon_version" );
if( lua_tointeger( L, -1 ) != MOON_VERSION )
luaL_error( L, "'%s' is not a moon %d.%d object type", tname,
MOON_VERSION_MAJOR, MOON_VERSION_MINOR );
lua_pop( L, 1 );
}
/* Pushes the metatable for the given type onto the Lua stack, and
* makes sure that the given type is a moon object type. */
static void moon_push_metatable_( lua_State* L, char const* tname ) {
moon_check_tname_( L, tname );
luaL_getmetatable( L, tname );
moon_check_metatable_( L, tname );
}
MOON_API void* moon_newobject( lua_State* L, char const* tname,
void (*gc)( void* ) ) {
moon_object_header* obj = NULL;
size_t off1 = 0;
#ifdef _MSC_VER
# pragma warning(push)
# pragma warning(disable: 4116)
#endif
size_t off2 = MOON_ROUNDTO_( sizeof( moon_object_header ),
MOON_OBJ_ALIGNMENT_ );
size_t sz = 0;
luaL_checkstack( L, 2, "moon_newobject" );
moon_push_metatable_( L, tname );
lua_getfield( L, -1, "__moon_size" );
sz = lua_tointeger( L, -1 );
lua_pop( L, 1 );
if( sz == 0 )
luaL_error( L, "type '%s' is incomplete (size is 0)", tname );
if( gc != 0 ) {
off1 = MOON_ROUNDTO_( sizeof( moon_object_header ),
MOON_GCF_ALIGNMENT_ );
off2 = MOON_ROUNDTO_( off1 + sizeof( moon_object_destructor ),
MOON_OBJ_ALIGNMENT_ );
#ifdef _MSC_VER
# pragma warning(pop)
#endif
}
obj = (moon_object_header*)lua_newuserdata( L, sz+off2 );
if( off1 > 0 ) {
moon_object_destructor* cl = NULL;
cl = (moon_object_destructor*)MOON_PTR_( obj, off1 );
*cl = gc;
}
obj->cleanup_offset = off1;
obj->object_offset = off2;
obj->vcheck_offset = 0;
obj->flags = MOON_OBJECT_IS_VALID;
lua_insert( L, -2 );
lua_setmetatable( L, -2 );
return MOON_PTR_( obj, off2 );
}
MOON_API void** moon_newpointer( lua_State* L, char const* tname,
void (*gc)( void* ) ) {
moon_object_header* obj = NULL;
void** p = NULL;
size_t off1 = 0;
#ifdef _MSC_VER
# pragma warning(push)
# pragma warning(disable: 4116)
#endif
size_t off2 = MOON_ROUNDTO_( sizeof( moon_object_header ),
MOON_PTR_ALIGNMENT_ );
luaL_checkstack( L, 2, "moon_newpointer" );
moon_push_metatable_( L, tname );
if( gc != 0 ) {
off1 = MOON_ROUNDTO_( sizeof( moon_object_header ),
MOON_GCF_ALIGNMENT_ );
off2 = MOON_ROUNDTO_( off1 + sizeof( moon_object_destructor ),
MOON_PTR_ALIGNMENT_ );
#ifdef _MSC_VER
# pragma warning(pop)
#endif
}
obj = (moon_object_header*)lua_newuserdata( L, sizeof( void* )+off2 );
p = (void**)MOON_PTR_( obj, off2 );
*p = NULL;
if( off1 > 0 ) {
moon_object_destructor* cl = NULL;
cl = (moon_object_destructor*)MOON_PTR_( obj, off1 );
*cl = gc;
}
obj->cleanup_offset = off1;
obj->object_offset = off2;
obj->vcheck_offset = 0;
obj->flags = MOON_OBJECT_IS_VALID | MOON_OBJECT_IS_POINTER;
lua_insert( L, -2 );
lua_setmetatable( L, -2 );
return p;
}
MOON_API void** moon_newfield( lua_State* L, char const* tname,
int idx, int (*isvalid)( void* ),
void* tagp ) {
moon_object_header* obj = NULL;
moon_object_vcheck_* nextcheck = NULL;
void** p = NULL;
size_t off1 = 0;
#ifdef _MSC_VER
# pragma warning(push)
# pragma warning(disable: 4116)
#endif
size_t off2 = MOON_ROUNDTO_( sizeof( moon_object_header ),
MOON_PTR_ALIGNMENT_ );
luaL_checkstack( L, 3, "moon_newfield" );
if( idx != 0 ) {
moon_object_header* h = (moon_object_header*)lua_touserdata( L, idx );
idx = moon_absindex( L, idx );
if( h != NULL && lua_getmetatable( L, idx ) ) {
lua_getfield( L, -1, "__moon_version" );
if( lua_tointeger( L, -1 ) == MOON_VERSION ) {
if( h->vcheck_offset > 0 ) {
moon_object_vcheck_* vc = NULL;
vc = (moon_object_vcheck_*)MOON_PTR_( h, h->vcheck_offset );
if( isvalid == 0 ) { /* inherit vcheck from idx object */
isvalid = vc->check;
tagp = vc->tagp;
nextcheck = vc->next;
} else /* add it to the chain */
nextcheck = vc;
}
}
lua_pop( L, 2 );
}
}
moon_push_metatable_( L, tname );
if( isvalid != 0 ) {
off1 = MOON_ROUNDTO_( sizeof( moon_object_header ),
MOON_VCK_ALIGNMENT_ );
off2 = MOON_ROUNDTO_( off1 + sizeof( moon_object_vcheck_ ),
MOON_PTR_ALIGNMENT_ );
#ifdef _MSC_VER
# pragma warning(pop)
#endif
}
obj = (moon_object_header*)lua_newuserdata( L, sizeof( void* )+off2 );
p = (void**)MOON_PTR_( obj, off2 );
*p = NULL;
obj->vcheck_offset = off1;
obj->object_offset = off2;
obj->cleanup_offset = 0;
obj->flags = MOON_OBJECT_IS_VALID | MOON_OBJECT_IS_POINTER;
if( off1 > 0 ) {
moon_object_vcheck_* vc = NULL;
vc= (moon_object_vcheck_*)MOON_PTR_( obj, off1 );
vc->check = isvalid;
vc->tagp = tagp;
vc->next = nextcheck;
}
lua_insert( L, -2 );
lua_setmetatable( L, -2 );
if( idx != 0 ) {
lua_newtable( L );
lua_pushvalue( L, idx );
lua_rawseti( L, -2, 1 );
#if LUA_VERSION_NUM < 502
lua_setfenv( L, -2 );
#else
lua_setuservalue( L, -2 );
#endif
}
return p;
}
MOON_API int moon_getmethods( lua_State* L, char const* tname ) {
int t = 0;
luaL_checkstack( L, 2, "moon_getmethods" );
moon_push_metatable_( L, tname );
lua_getfield( L, -1, "__index" );
lua_replace( L, -2 );
t = lua_type( L, -1 );
if( t == LUA_TTABLE )
return t;
else if( t == LUA_TFUNCTION ) {
lua_CFunction dispatch = moon_getf_( L, "index",
moon_index_dispatch_ );
if( lua_tocfunction( L, -1 ) == dispatch &&
lua_getupvalue( L, -1, 1 ) != NULL ) {
lua_replace( L, -2 );
if( lua_type( L, -1 ) == LUA_TTABLE )
return LUA_TTABLE;
}
}
lua_pop( L, 1 );
return LUA_TNIL;
}
MOON_API void moon_killobject( lua_State* L, int idx ) {
moon_object_header* h = (moon_object_header*)lua_touserdata( L, idx );
luaL_checkstack( L, 2, "moon_killobject" );
if( h == NULL || !lua_getmetatable( L, idx ) )
moon_type_error_version_( L, idx );
lua_getfield( L, -1, "__moon_version" );
if( lua_tointeger( L, -1 ) != MOON_VERSION )
moon_type_error_version_( L, idx );
lua_pop( L, 2 );
moon_object_run_destructor_( h );
}
MOON_API void moon_defcast( lua_State* L, char const* tname1,
char const* tname2,
moon_object_cast cast ) {
luaL_checkstack( L, 2, "moon_defcast" );
moon_push_metatable_( L, tname1 );
moon_check_tname_( L, tname2 );
lua_pushcfunction( L, (lua_CFunction)(void(*)(void))cast );
lua_setfield( L, -2, tname2 );
lua_pop( L, 1 );
}
/* Validates a chain of vcheck objects. The chain won't be long, so
* a recursive approach should be fine! */
static int moon_validate_vcheck_( moon_object_vcheck_ const* vc ) {
if( vc->next != NULL )
return moon_validate_vcheck_( vc->next ) &&
(vc->check == 0 || vc->check( vc->tagp ));
else
return vc->check == 0 || vc->check( vc->tagp );
}
MOON_API void* moon_checkobject( lua_State* L, int idx,
char const* tname ) {
moon_object_header* h = (moon_object_header*)lua_touserdata( L, idx );
void* p = NULL;
int res = 0;
moon_object_cast cast = 0;
moon_check_tname_( L, tname );
luaL_checkstack( L, 3, "moon_checkobject" );
idx = moon_absindex( L, idx );
if( h == NULL )
moon_type_error_( L, idx, tname, luaL_typename( L, idx ) );
if( lua_islightuserdata( L, idx ) )
moon_type_error_( L, idx, tname, "lightuserdata" );
if( !lua_getmetatable( L, idx ) )
moon_type_error_( L, idx, tname, "userdata" );
lua_getfield( L, -1, "__moon_version" );
if( lua_tointeger( L, -1 ) != MOON_VERSION ) {
lua_pop( L, 2 );
moon_type_error_version_( L, idx );
}
lua_pop( L, 1 );
luaL_getmetatable( L, tname );
res = lua_rawequal( L, -1, -2 );
lua_pop( L, 1 );
if( !res ) {
lua_getfield( L, -1, tname );
cast = (moon_object_cast)(void(*)(void))lua_tocfunction( L, -1 );
lua_pop( L, 1 );
if( cast == 0 ) {
char const* name = NULL;
lua_getfield( L, -1, "__name" );
name = lua_tostring( L, -1 );
moon_type_error_( L, idx, tname, name ? name : "userdata" );
}
}
lua_pop( L, 1 );
if( !(h->flags & MOON_OBJECT_IS_VALID) )
moon_type_error_invalid_( L, idx, tname );
if( h->vcheck_offset > 0 ) {
moon_object_vcheck_* vc = NULL;
vc = (moon_object_vcheck_*)MOON_PTR_( h, h->vcheck_offset );
if( !moon_validate_vcheck_( vc ) )
moon_type_error_invalid_( L, idx, tname );
}
p = MOON_PTR_( h, h->object_offset );
if( h->flags & MOON_OBJECT_IS_POINTER )
p = *((void**)p);
if( p == NULL )
moon_type_error_invalid_( L, idx, tname );
if( cast != 0 ) {
p = cast( p );
if( p == NULL )
moon_type_error_invalid_( L, idx, tname );
}
return p;
}
MOON_API void* moon_testobject( lua_State* L, int idx,
char const* tname ) {
moon_object_header* h = (moon_object_header*)lua_touserdata( L, idx );
void* p = NULL;
int res = 0;
moon_object_cast cast = 0;
moon_check_tname_( L, tname );
luaL_checkstack( L, 2, "moon_testobject" );
if( h == NULL || !lua_getmetatable( L, idx ) )
return NULL;
lua_getfield( L, -1, "__moon_version" );
if( lua_tointeger( L, -1 ) != MOON_VERSION ) {
lua_pop( L, 2 );
return NULL;
}
lua_pop( L, 1 );
luaL_getmetatable( L, tname );
res = lua_rawequal( L, -1, -2 );
lua_pop( L, 1 );
if( !res ) {
lua_getfield( L, -1, tname );
cast = (moon_object_cast)(void(*)(void))lua_tocfunction( L, -1 );
lua_pop( L, 2 );
if( cast == 0 )
return NULL;
} else
lua_pop( L, 1 );
if( !(h->flags & MOON_OBJECT_IS_VALID) )
return NULL;
if( h->vcheck_offset > 0 ) {
moon_object_vcheck_* vc = NULL;
vc = (moon_object_vcheck_*)MOON_PTR_( h, h->vcheck_offset );
if( !moon_validate_vcheck_( vc ) )
return NULL;
}
p = MOON_PTR_( h, h->object_offset );
if( h->flags & MOON_OBJECT_IS_POINTER )
p = *((void**)p);
if( cast != 0 )
p = cast( p );
return p;
}
static void* moon_cast_id_( void* p ) {
return p;
}
static void moon_copy_table_( lua_State* L, int src, int dst ) {
src = moon_absindex( L, src );
dst = moon_absindex( L, dst );
lua_pushnil( L );
while( lua_next( L, src ) ) {
lua_pushvalue( L, -2 ); /* duplicate key */
lua_pushvalue( L, -2 ); /* duplicate value */
lua_rawset( L, dst );
lua_pop( L, 1 ); /* pop value */
}
}
MOON_LLINKAGE_BEGIN
MOON_API int moon_derive( lua_State* L ) {
char const* newtype = luaL_checkstring( L, 1 );
char const* oldtype = luaL_checkstring( L, 2 );
int t = 0;
lua_settop( L, 2 );
moon_check_tname_( L, newtype );
lua_pushvalue( L, 1 );
lua_rawget( L, LUA_REGISTRYINDEX );
luaL_argcheck( L, lua_isnil( L, -1 ), 1,
"attempt to redefine type" );
lua_pop( L, 1 );
lua_pushvalue( L, 2 );
lua_rawget( L, LUA_REGISTRYINDEX ); /* 3: old metatable */
moon_check_metatable_( L, oldtype );
/* clone metatable */
lua_newtable( L ); /* 4: new metatable */
moon_copy_table_( L, 3, 4 );
/* replace __tostring */
lua_pushvalue( L, 1 );
lua_pushcclosure( L, moon_object_default_tostring_, 1 );
lua_setfield( L, 4, "__tostring" );
/* add cast to old type */
lua_pushvalue( L, 2 );
lua_pushcfunction( L, moon_getf_( L, "cast",
(lua_CFunction)(void(*)(void))moon_cast_id_ ) );
lua_rawset( L, 4 );
/* replace __index metamethod */
lua_pushliteral( L, "__index" );
lua_rawget( L, 4 ); /* 5: __index metamethod */
t = lua_type( L, 5 );
lua_newtable( L ); /* 6: new methods table */
lua_pushliteral( L, "__index" ); /* 7: string "__index" */
if( t == LUA_TTABLE ) {
moon_copy_table_( L, 5, 6 );
lua_pushvalue( L, 6 ); /* 8: new methods table */
} else if( t == LUA_TFUNCTION ) {
lua_CFunction dispatch = moon_getf_( L, "index",
moon_index_dispatch_ );
if( lua_tocfunction( L, 5 ) == dispatch ) {
lua_getupvalue( L, 5, 1 ); /* 8: old methods table */
if( lua_istable( L, -1 ) )
moon_copy_table_( L, -1, 6 );
lua_pop( L, 1 );
lua_pushvalue( L, 6 ); /* 8: new methods table */
lua_getupvalue( L, 5, 2 ); /* 9: properties */
lua_getupvalue( L, 5, 3 ); /* 10: index func */
lua_pushcclosure( L, dispatch, 3 ); /* 8: dispatcher */
} else {
lua_pushvalue( L, 6 ); /* 8: new methods table */
lua_pushnil( L ); /* 9: no properties */
lua_pushvalue( L, 5 ); /* 10: index func */
lua_pushcclosure( L, dispatch, 3 ); /* 8: dispatcher */
}
} else
lua_pushvalue( L, 6 ); /* 8: new methods table */
lua_rawset( L, 4 );
/* register new type */
lua_pushvalue( L, 1 );
lua_pushvalue( L, 4 );
lua_rawset( L, LUA_REGISTRYINDEX );
return 1;
}
MOON_LLINKAGE_END
MOON_LLINKAGE_BEGIN
MOON_API int moon_downcast( lua_State* L ) {
void* h = lua_touserdata( L, 1 );
char const* tname = luaL_checkstring( L, 2 );
moon_object_cast cast = 0, id_cast = 0;
lua_settop( L, 2 );
luaL_argcheck( L, h != NULL && lua_getmetatable( L, 1 ), 1,
"object expected" ); /* 3: metatable */
luaL_argcheck( L, lua_istable( L, -1 ), 1, "object expected" );
lua_getfield( L, -1, "__moon_version" );
luaL_argcheck( L, lua_tointeger( L, -1 ) == MOON_VERSION, 1,
"object expected" );
lua_pop( L, 1 );
moon_check_tname_( L, tname );
lua_getfield( L, -1, "__name" ); /* 4: __name */
lua_pushvalue( L, 2 );
lua_rawget( L, LUA_REGISTRYINDEX ); /* 5: metatable */
moon_check_metatable_( L, tname );
lua_pushvalue( L, 4 );
lua_rawget( L, 5 ); /* 6: cast function */
cast = (moon_object_cast)(void(*)(void))lua_tocfunction( L, -1 );
id_cast = (moon_object_cast)(void(*)(void))moon_getf_( L, "cast", (lua_CFunction)(void(*)(void))moon_cast_id_ );
luaL_argcheck( L, cast == id_cast, 1, "invalid downcast" );
lua_pop( L, 1 );
lua_setmetatable( L, 1 );
lua_settop( L, 1 );
return 1;
}
MOON_LLINKAGE_END
MOON_API lua_Integer moon_checkint( lua_State* L, int idx,
lua_Integer low,
lua_Integer high ) {
lua_Integer v = luaL_checkinteger( L, idx );
int valid = (high < low) ? (low <= v || v <= high)
: (low <= v && v <= high);
if( !valid ) {
char const* msg = NULL;
#if LUA_VERSION_NUM >= 503
msg = lua_pushfstring( L, "value out of range [%I,%I]", low, high );
#else
if( low >= INT_MIN && low <= INT_MAX &&
high >= INT_MIN && high <= INT_MAX )
msg = lua_pushfstring( L, "value out of range [%d,%d]",
(int)low, (int)high );
else
msg = lua_pushfstring( L, "value out of range [%f,%f]",
(lua_Number)low, (lua_Number)high );
#endif
luaL_argerror( L, idx, msg );
}
return v;
}
MOON_API lua_Integer moon_optint( lua_State* L, int idx,
lua_Integer low, lua_Integer high,
lua_Integer def ) {
if( !lua_isnoneornil( L, idx ) )
def = moon_checkint( L, idx, low, high );
return def;
}
MOON_API int* moon_atexit( lua_State* L, lua_CFunction func ) {
int* flag = NULL;
luaL_checkstack( L, 3, "moon_atexit" );
flag = (int*)lua_newuserdata( L, sizeof( int ) );
*flag = 0;
/* setmetatable( flag, { __gc = func } ) */
lua_newtable( L );
lua_pushcfunction( L, func );
lua_setfield( L, -2, "__gc" );
lua_setmetatable( L, -2 );
/* registry[ flag ] = flag */
lua_pushvalue( L, -1 );
lua_pushvalue( L, -2 );
lua_settable( L, LUA_REGISTRYINDEX );
return flag;
}
MOON_API void moon_setuvfield( lua_State* L, int i, char const* key ) {
luaL_checkstack( L, 2, "moon_setuvfield" );
#if LUA_VERSION_NUM < 502
lua_getfenv( L, i );
#else
lua_getuservalue( L, i );
#endif
if( !lua_istable( L, -1 ) )
luaL_error( L, "attempt to add to non-table uservalue" );
lua_pushvalue( L, -2 );
lua_setfield( L, -2, key );
lua_pop( L, 2 );
}
MOON_API int moon_getuvfield( lua_State* L, int i, char const* key ) {
luaL_checkstack( L, 2, "moon_getuvfield" );
#if LUA_VERSION_NUM < 502
lua_getfenv( L, i );
#else
lua_getuservalue( L, i );
#endif
if( lua_istable( L, -1 ) ) {
int t = 0;
lua_getfield( L, -1, key );
lua_replace( L, -2 );
t = lua_type( L, -1 );
if( t != LUA_TNIL )
return t;
}
lua_pop( L, 1 );
return LUA_TNIL;
}
MOON_API void moon_getcache( lua_State* L, int index ) {
static char xyz = 0; /* used as a unique key */
luaL_checkstack( L, 3, "moon_getcache" );
index = moon_absindex( L, index );
lua_pushlightuserdata( L, &xyz );
lua_rawget( L, index );
if( !lua_istable( L, -1 ) ) {