forked from google/flatbuffers
-
Notifications
You must be signed in to change notification settings - Fork 0
/
idl_gen_go.cpp
1415 lines (1280 loc) · 51.6 KB
/
idl_gen_go.cpp
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 2014 Google Inc. All rights reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
// independent from idl_parser, since this code is not needed for most clients
#include <algorithm>
#include <sstream>
#include <string>
#include "flatbuffers/code_generators.h"
#include "flatbuffers/flatbuffers.h"
#include "flatbuffers/idl.h"
#include "flatbuffers/util.h"
#include "idl_namer.h"
#ifdef _WIN32
# include <direct.h>
# define PATH_SEPARATOR "\\"
# define mkdir(n, m) _mkdir(n)
#else
# include <sys/stat.h>
# define PATH_SEPARATOR "/"
#endif
namespace flatbuffers {
namespace go {
namespace {
// see https://golang.org/ref/spec#Keywords
static std::set<std::string> GoKeywords() {
return {
"break", "default", "func", "interface", "select",
"case", "defer", "go", "map", "struct",
"chan", "else", "goto", "package", "switch",
"const", "fallthrough", "if", "range", "type",
"continue", "for", "import", "return", "var",
};
}
static Namer::Config GoDefaultConfig() {
// Note that the functions with user defined types in the name use
// upper camel case for all but the user defined type itself, which is keep
// cased. Despite being a function, we interpret it as a Type.
return { /*types=*/Case::kKeep,
/*constants=*/Case::kUnknown,
/*methods=*/Case::kUpperCamel,
/*functions=*/Case::kUpperCamel,
/*fields=*/Case::kUpperCamel,
/*variables=*/Case::kLowerCamel,
/*variants=*/Case::kKeep,
/*enum_variant_seperator=*/"", // I.e. Concatenate.
/*escape_keywords=*/Namer::Config::Escape::AfterConvertingCase,
/*namespaces=*/Case::kKeep,
/*namespace_seperator=*/"__",
/*object_prefix=*/"",
/*object_suffix=*/"T",
/*keyword_prefix=*/"",
/*keyword_suffix=*/"_",
/*filenames=*/Case::kKeep,
/*directories=*/Case::kKeep,
/*output_path=*/"",
/*filename_suffix=*/"",
/*filename_extension=*/".go" };
}
} // namespace
class GoGenerator : public BaseGenerator {
public:
GoGenerator(const Parser &parser, const std::string &path,
const std::string &file_name, const std::string &go_namespace)
: BaseGenerator(parser, path, file_name, "" /* not used*/,
"" /* not used */, "go"),
cur_name_space_(nullptr),
namer_(WithFlagOptions(GoDefaultConfig(), parser.opts, path),
GoKeywords()) {
std::istringstream iss(go_namespace);
std::string component;
while (std::getline(iss, component, '.')) {
go_namespace_.components.push_back(component);
}
}
bool generate() {
std::string one_file_code;
bool needs_imports = false;
for (auto it = parser_.enums_.vec.begin(); it != parser_.enums_.vec.end();
++it) {
tracked_imported_namespaces_.clear();
needs_imports = false;
std::string enumcode;
GenEnum(**it, &enumcode);
if ((*it)->is_union && parser_.opts.generate_object_based_api) {
GenNativeUnion(**it, &enumcode);
GenNativeUnionPack(**it, &enumcode);
GenNativeUnionUnPack(**it, &enumcode);
needs_imports = true;
}
if (parser_.opts.one_file) {
one_file_code += enumcode;
} else {
if (!SaveType(**it, enumcode, needs_imports, true)) return false;
}
}
for (auto it = parser_.structs_.vec.begin();
it != parser_.structs_.vec.end(); ++it) {
tracked_imported_namespaces_.clear();
std::string declcode;
GenStruct(**it, &declcode);
if (parser_.opts.one_file) {
one_file_code += declcode;
} else {
if (!SaveType(**it, declcode, true, false)) return false;
}
}
if (parser_.opts.one_file) {
std::string code = "";
const bool is_enum = !parser_.enums_.vec.empty();
BeginFile(LastNamespacePart(go_namespace_), true, is_enum, &code);
code += one_file_code;
const std::string filename =
GeneratedFileName(path_, file_name_, parser_.opts);
return SaveFile(filename.c_str(), code, false);
}
return true;
}
private:
Namespace go_namespace_;
Namespace *cur_name_space_;
const IdlNamer namer_;
struct NamespacePtrLess {
bool operator()(const Namespace *a, const Namespace *b) const {
return *a < *b;
}
};
std::set<const Namespace *, NamespacePtrLess> tracked_imported_namespaces_;
// Most field accessors need to retrieve and test the field offset first,
// this is the prefix code for that.
std::string OffsetPrefix(const FieldDef &field) {
return "{\n\to := flatbuffers.UOffsetT(rcv._tab.Offset(" +
NumToString(field.value.offset) + "))\n\tif o != 0 {\n";
}
// Begin a class declaration.
void BeginClass(const StructDef &struct_def, std::string *code_ptr) {
std::string &code = *code_ptr;
code += "type " + namer_.Type(struct_def) + " struct {\n\t";
// _ is reserved in flatbuffers field names, so no chance of name conflict:
code += "_tab ";
code += struct_def.fixed ? "flatbuffers.Struct" : "flatbuffers.Table";
code += "\n}\n\n";
}
// Construct the name of the type for this enum.
std::string GetEnumTypeName(const EnumDef &enum_def) {
return WrapInNameSpaceAndTrack(enum_def.defined_namespace,
namer_.Type(enum_def));
}
// Create a type for the enum values.
void GenEnumType(const EnumDef &enum_def, std::string *code_ptr) {
std::string &code = *code_ptr;
code += "type " + GetEnumTypeName(enum_def) + " ";
code += GenTypeBasic(enum_def.underlying_type) + "\n\n";
}
// Begin enum code with a class declaration.
void BeginEnum(std::string *code_ptr) {
std::string &code = *code_ptr;
code += "const (\n";
}
// A single enum member.
void EnumMember(const EnumDef &enum_def, const EnumVal &ev,
size_t max_name_length, std::string *code_ptr) {
std::string &code = *code_ptr;
code += "\t";
code += namer_.EnumVariant(enum_def, ev);
code += " ";
code += std::string(max_name_length - ev.name.length(), ' ');
code += GetEnumTypeName(enum_def);
code += " = ";
code += enum_def.ToString(ev) + "\n";
}
// End enum code.
void EndEnum(std::string *code_ptr) {
std::string &code = *code_ptr;
code += ")\n\n";
}
// Begin enum name map.
void BeginEnumNames(const EnumDef &enum_def, std::string *code_ptr) {
std::string &code = *code_ptr;
code += "var EnumNames";
code += enum_def.name;
code += " = map[" + GetEnumTypeName(enum_def) + "]string{\n";
}
// A single enum name member.
void EnumNameMember(const EnumDef &enum_def, const EnumVal &ev,
size_t max_name_length, std::string *code_ptr) {
std::string &code = *code_ptr;
code += "\t";
code += namer_.EnumVariant(enum_def, ev);
code += ": ";
code += std::string(max_name_length - ev.name.length(), ' ');
code += "\"";
code += ev.name;
code += "\",\n";
}
// End enum name map.
void EndEnumNames(std::string *code_ptr) {
std::string &code = *code_ptr;
code += "}\n\n";
}
// Generate String() method on enum type.
void EnumStringer(const EnumDef &enum_def, std::string *code_ptr) {
std::string &code = *code_ptr;
const std::string enum_type = namer_.Type(enum_def);
code += "func (v " + enum_type + ") String() string {\n";
code += "\tif s, ok := EnumNames" + enum_type + "[v]; ok {\n";
code += "\t\treturn s\n";
code += "\t}\n";
code += "\treturn \"" + enum_def.name;
code += "(\" + strconv.FormatInt(int64(v), 10) + \")\"\n";
code += "}\n\n";
}
// Begin enum value map.
void BeginEnumValues(const EnumDef &enum_def, std::string *code_ptr) {
std::string &code = *code_ptr;
code += "var EnumValues";
code += namer_.Type(enum_def);
code += " = map[string]" + GetEnumTypeName(enum_def) + "{\n";
}
// A single enum value member.
void EnumValueMember(const EnumDef &enum_def, const EnumVal &ev,
size_t max_name_length, std::string *code_ptr) {
std::string &code = *code_ptr;
code += "\t\"";
code += ev.name;
code += "\": ";
code += std::string(max_name_length - ev.name.length(), ' ');
code += namer_.EnumVariant(enum_def, ev);
code += ",\n";
}
// End enum value map.
void EndEnumValues(std::string *code_ptr) {
std::string &code = *code_ptr;
code += "}\n\n";
}
// Initialize a new struct or table from existing data.
void NewRootTypeFromBuffer(const StructDef &struct_def,
std::string *code_ptr) {
std::string &code = *code_ptr;
const std::string size_prefix[] = { "", "SizePrefixed" };
const std::string struct_type = namer_.Type(struct_def);
for (int i = 0; i < 2; i++) {
code += "func Get" + size_prefix[i] + "RootAs" + struct_type;
code += "(buf []byte, offset flatbuffers.UOffsetT) ";
code += "*" + struct_type + "";
code += " {\n";
if (i == 0) {
code += "\tn := flatbuffers.GetUOffsetT(buf[offset:])\n";
} else {
code +=
"\tn := "
"flatbuffers.GetUOffsetT(buf[offset+flatbuffers.SizeUint32:])\n";
}
code += "\tx := &" + struct_type + "{}\n";
if (i == 0) {
code += "\tx.Init(buf, n+offset)\n";
} else {
code += "\tx.Init(buf, n+offset+flatbuffers.SizeUint32)\n";
}
code += "\treturn x\n";
code += "}\n\n";
}
}
// Initialize an existing object with other data, to avoid an allocation.
void InitializeExisting(const StructDef &struct_def, std::string *code_ptr) {
std::string &code = *code_ptr;
GenReceiver(struct_def, code_ptr);
code += " Init(buf []byte, i flatbuffers.UOffsetT) ";
code += "{\n";
code += "\trcv._tab.Bytes = buf\n";
code += "\trcv._tab.Pos = i\n";
code += "}\n\n";
}
// Implement the table accessor
void GenTableAccessor(const StructDef &struct_def, std::string *code_ptr) {
std::string &code = *code_ptr;
GenReceiver(struct_def, code_ptr);
code += " Table() flatbuffers.Table ";
code += "{\n";
if (struct_def.fixed) {
code += "\treturn rcv._tab.Table\n";
} else {
code += "\treturn rcv._tab\n";
}
code += "}\n\n";
}
// Get the length of a vector.
void GetVectorLen(const StructDef &struct_def, const FieldDef &field,
std::string *code_ptr) {
std::string &code = *code_ptr;
GenReceiver(struct_def, code_ptr);
code += " " + namer_.Function(field) + "Length(";
code += ") int " + OffsetPrefix(field);
code += "\t\treturn rcv._tab.VectorLen(o)\n\t}\n";
code += "\treturn 0\n}\n\n";
}
// Get a [ubyte] vector as a byte slice.
void GetUByteSlice(const StructDef &struct_def, const FieldDef &field,
std::string *code_ptr) {
std::string &code = *code_ptr;
GenReceiver(struct_def, code_ptr);
code += " " + namer_.Function(field) + "Bytes(";
code += ") []byte " + OffsetPrefix(field);
code += "\t\treturn rcv._tab.ByteVector(o + rcv._tab.Pos)\n\t}\n";
code += "\treturn nil\n}\n\n";
}
// Get the value of a struct's scalar.
void GetScalarFieldOfStruct(const StructDef &struct_def,
const FieldDef &field, std::string *code_ptr) {
std::string &code = *code_ptr;
std::string getter = GenGetter(field.value.type);
GenReceiver(struct_def, code_ptr);
code += " " + namer_.Function(field);
code += "() " + TypeName(field) + " {\n";
code += "\treturn " +
CastToEnum(field.value.type,
getter + "(rcv._tab.Pos + flatbuffers.UOffsetT(" +
NumToString(field.value.offset) + "))");
code += "\n}\n";
}
// Get the value of a table's scalar.
void GetScalarFieldOfTable(const StructDef &struct_def, const FieldDef &field,
std::string *code_ptr) {
std::string &code = *code_ptr;
std::string getter = GenGetter(field.value.type);
GenReceiver(struct_def, code_ptr);
code += " " + namer_.Function(field);
code += "() " + TypeName(field) + " ";
code += OffsetPrefix(field);
if (field.IsScalarOptional()) {
code += "\t\tv := ";
} else {
code += "\t\treturn ";
}
code += CastToEnum(field.value.type, getter + "(o + rcv._tab.Pos)");
if (field.IsScalarOptional()) { code += "\n\t\treturn &v"; }
code += "\n\t}\n";
code += "\treturn " + GenConstant(field) + "\n";
code += "}\n\n";
}
// Get a struct by initializing an existing struct.
// Specific to Struct.
void GetStructFieldOfStruct(const StructDef &struct_def,
const FieldDef &field, std::string *code_ptr) {
std::string &code = *code_ptr;
GenReceiver(struct_def, code_ptr);
code += " " + namer_.Function(field);
code += "(obj *" + TypeName(field);
code += ") *" + TypeName(field);
code += " {\n";
code += "\tif obj == nil {\n";
code += "\t\tobj = new(" + TypeName(field) + ")\n";
code += "\t}\n";
code += "\tobj.Init(rcv._tab.Bytes, rcv._tab.Pos+";
code += NumToString(field.value.offset) + ")";
code += "\n\treturn obj\n";
code += "}\n";
}
// Get a struct by initializing an existing struct.
// Specific to Table.
void GetStructFieldOfTable(const StructDef &struct_def, const FieldDef &field,
std::string *code_ptr) {
std::string &code = *code_ptr;
GenReceiver(struct_def, code_ptr);
code += " " + namer_.Function(field);
code += "(obj *";
code += TypeName(field);
code += ") *" + TypeName(field) + " " + OffsetPrefix(field);
if (field.value.type.struct_def->fixed) {
code += "\t\tx := o + rcv._tab.Pos\n";
} else {
code += "\t\tx := rcv._tab.Indirect(o + rcv._tab.Pos)\n";
}
code += "\t\tif obj == nil {\n";
code += "\t\t\tobj = new(" + TypeName(field) + ")\n";
code += "\t\t}\n";
code += "\t\tobj.Init(rcv._tab.Bytes, x)\n";
code += "\t\treturn obj\n\t}\n\treturn nil\n";
code += "}\n\n";
}
// Get the value of a string.
void GetStringField(const StructDef &struct_def, const FieldDef &field,
std::string *code_ptr) {
std::string &code = *code_ptr;
GenReceiver(struct_def, code_ptr);
code += " " + namer_.Function(field);
code += "() " + TypeName(field) + " ";
code += OffsetPrefix(field) + "\t\treturn " + GenGetter(field.value.type);
code += "(o + rcv._tab.Pos)\n\t}\n\treturn nil\n";
code += "}\n\n";
}
// Get the value of a union from an object.
void GetUnionField(const StructDef &struct_def, const FieldDef &field,
std::string *code_ptr) {
std::string &code = *code_ptr;
GenReceiver(struct_def, code_ptr);
code += " " + namer_.Function(field) + "(";
code += "obj " + GenTypePointer(field.value.type) + ") bool ";
code += OffsetPrefix(field);
code += "\t\t" + GenGetter(field.value.type);
code += "(obj, o)\n\t\treturn true\n\t}\n";
code += "\treturn false\n";
code += "}\n\n";
}
// Get the value of a vector's struct member.
void GetMemberOfVectorOfStruct(const StructDef &struct_def,
const FieldDef &field, std::string *code_ptr) {
std::string &code = *code_ptr;
auto vectortype = field.value.type.VectorType();
GenReceiver(struct_def, code_ptr);
code += " " + namer_.Function(field);
code += "(obj *" + TypeName(field);
code += ", j int) bool " + OffsetPrefix(field);
code += "\t\tx := rcv._tab.Vector(o)\n";
code += "\t\tx += flatbuffers.UOffsetT(j) * ";
code += NumToString(InlineSize(vectortype)) + "\n";
if (!(vectortype.struct_def->fixed)) {
code += "\t\tx = rcv._tab.Indirect(x)\n";
}
code += "\t\tobj.Init(rcv._tab.Bytes, x)\n";
code += "\t\treturn true\n\t}\n";
code += "\treturn false\n";
code += "}\n\n";
}
// Get the value of a vector's non-struct member.
void GetMemberOfVectorOfNonStruct(const StructDef &struct_def,
const FieldDef &field,
std::string *code_ptr) {
std::string &code = *code_ptr;
auto vectortype = field.value.type.VectorType();
GenReceiver(struct_def, code_ptr);
code += " " + namer_.Function(field);
code += "(j int) " + TypeName(field) + " ";
code += OffsetPrefix(field);
code += "\t\ta := rcv._tab.Vector(o)\n";
code += "\t\treturn " +
CastToEnum(field.value.type,
GenGetter(field.value.type) +
"(a + flatbuffers.UOffsetT(j*" +
NumToString(InlineSize(vectortype)) + "))");
code += "\n\t}\n";
if (IsString(vectortype)) {
code += "\treturn nil\n";
} else if (vectortype.base_type == BASE_TYPE_BOOL) {
code += "\treturn false\n";
} else {
code += "\treturn 0\n";
}
code += "}\n\n";
}
// Begin the creator function signature.
void BeginBuilderArgs(const StructDef &struct_def, std::string *code_ptr) {
std::string &code = *code_ptr;
if (code.substr(code.length() - 2) != "\n\n") {
// a previous mutate has not put an extra new line
code += "\n";
}
code += "func Create" + struct_def.name;
code += "(builder *flatbuffers.Builder";
}
// Recursively generate arguments for a constructor, to deal with nested
// structs.
void StructBuilderArgs(const StructDef &struct_def, const char *nameprefix,
std::string *code_ptr) {
for (auto it = struct_def.fields.vec.begin();
it != struct_def.fields.vec.end(); ++it) {
auto &field = **it;
if (IsStruct(field.value.type)) {
// Generate arguments for a struct inside a struct. To ensure names
// don't clash, and to make it obvious these arguments are constructing
// a nested struct, prefix the name with the field name.
StructBuilderArgs(*field.value.type.struct_def,
(nameprefix + (field.name + "_")).c_str(), code_ptr);
} else {
std::string &code = *code_ptr;
code += std::string(", ") + nameprefix;
code += namer_.Variable(field);
code += " " + TypeName(field);
}
}
}
// End the creator function signature.
void EndBuilderArgs(std::string *code_ptr) {
std::string &code = *code_ptr;
code += ") flatbuffers.UOffsetT {\n";
}
// Recursively generate struct construction statements and instert manual
// padding.
void StructBuilderBody(const StructDef &struct_def, const char *nameprefix,
std::string *code_ptr) {
std::string &code = *code_ptr;
code += "\tbuilder.Prep(" + NumToString(struct_def.minalign) + ", ";
code += NumToString(struct_def.bytesize) + ")\n";
for (auto it = struct_def.fields.vec.rbegin();
it != struct_def.fields.vec.rend(); ++it) {
auto &field = **it;
if (field.padding)
code += "\tbuilder.Pad(" + NumToString(field.padding) + ")\n";
if (IsStruct(field.value.type)) {
StructBuilderBody(*field.value.type.struct_def,
(nameprefix + (field.name + "_")).c_str(), code_ptr);
} else {
code += "\tbuilder.Prepend" + GenMethod(field) + "(";
code += CastToBaseType(field.value.type,
nameprefix + namer_.Variable(field)) +
")\n";
}
}
}
void EndBuilderBody(std::string *code_ptr) {
std::string &code = *code_ptr;
code += "\treturn builder.Offset()\n";
code += "}\n";
}
// Get the value of a table's starting offset.
void GetStartOfTable(const StructDef &struct_def, std::string *code_ptr) {
std::string &code = *code_ptr;
code += "func " + namer_.Type(struct_def) + "Start";
code += "(builder *flatbuffers.Builder) {\n";
code += "\tbuilder.StartObject(";
code += NumToString(struct_def.fields.vec.size());
code += ")\n}\n";
}
// Set the value of a table's field.
void BuildFieldOfTable(const StructDef &struct_def, const FieldDef &field,
const size_t offset, std::string *code_ptr) {
std::string &code = *code_ptr;
const std::string field_var = namer_.Variable(field);
code += "func " + namer_.Type(struct_def) + "Add" + namer_.Function(field);
code += "(builder *flatbuffers.Builder, ";
code += field_var + " ";
if (!IsScalar(field.value.type.base_type) && (!struct_def.fixed)) {
code += "flatbuffers.UOffsetT";
} else {
code += GenTypeGet(field.value.type);
}
code += ") {\n\t";
code += "builder.Prepend";
code += GenMethod(field);
if (field.IsScalarOptional()) {
code += "(";
} else {
code += "Slot(" + NumToString(offset) + ", ";
}
if (!IsScalar(field.value.type.base_type) && (!struct_def.fixed)) {
code += "flatbuffers.UOffsetT";
code += "(" + field_var + ")";
} else {
code += CastToBaseType(field.value.type, field_var);
}
if (field.IsScalarOptional()) {
code += ")\n";
code += "\tbuilder.Slot(" + NumToString(offset);
} else {
code += ", " + GenConstant(field);
}
code += ")\n";
code += "}\n";
}
// Set the value of one of the members of a table's vector.
void BuildVectorOfTable(const StructDef &struct_def, const FieldDef &field,
std::string *code_ptr) {
std::string &code = *code_ptr;
code += "func " + namer_.Type(struct_def) + "Start";
code += namer_.Function(field);
code += "Vector(builder *flatbuffers.Builder, numElems int) ";
code += "flatbuffers.UOffsetT {\n\treturn builder.StartVector(";
auto vector_type = field.value.type.VectorType();
auto alignment = InlineAlignment(vector_type);
auto elem_size = InlineSize(vector_type);
code += NumToString(elem_size);
code += ", numElems, " + NumToString(alignment);
code += ")\n}\n";
}
// Get the offset of the end of a table.
void GetEndOffsetOnTable(const StructDef &struct_def, std::string *code_ptr) {
std::string &code = *code_ptr;
code += "func " + namer_.Type(struct_def) + "End";
code += "(builder *flatbuffers.Builder) flatbuffers.UOffsetT ";
code += "{\n\treturn builder.EndObject()\n}\n";
}
// Generate the receiver for function signatures.
void GenReceiver(const StructDef &struct_def, std::string *code_ptr) {
std::string &code = *code_ptr;
code += "func (rcv *" + namer_.Type(struct_def) + ")";
}
// Generate a struct field getter, conditioned on its child type(s).
void GenStructAccessor(const StructDef &struct_def, const FieldDef &field,
std::string *code_ptr) {
GenComment(field.doc_comment, code_ptr, nullptr, "");
if (IsScalar(field.value.type.base_type)) {
if (struct_def.fixed) {
GetScalarFieldOfStruct(struct_def, field, code_ptr);
} else {
GetScalarFieldOfTable(struct_def, field, code_ptr);
}
} else {
switch (field.value.type.base_type) {
case BASE_TYPE_STRUCT:
if (struct_def.fixed) {
GetStructFieldOfStruct(struct_def, field, code_ptr);
} else {
GetStructFieldOfTable(struct_def, field, code_ptr);
}
break;
case BASE_TYPE_STRING:
GetStringField(struct_def, field, code_ptr);
break;
case BASE_TYPE_VECTOR: {
auto vectortype = field.value.type.VectorType();
if (vectortype.base_type == BASE_TYPE_STRUCT) {
GetMemberOfVectorOfStruct(struct_def, field, code_ptr);
} else {
GetMemberOfVectorOfNonStruct(struct_def, field, code_ptr);
}
break;
}
case BASE_TYPE_UNION: GetUnionField(struct_def, field, code_ptr); break;
default: FLATBUFFERS_ASSERT(0);
}
}
if (IsVector(field.value.type)) {
GetVectorLen(struct_def, field, code_ptr);
if (field.value.type.element == BASE_TYPE_UCHAR) {
GetUByteSlice(struct_def, field, code_ptr);
}
}
}
// Mutate the value of a struct's scalar.
void MutateScalarFieldOfStruct(const StructDef &struct_def,
const FieldDef &field, std::string *code_ptr) {
std::string &code = *code_ptr;
std::string setter =
"rcv._tab.Mutate" + namer_.Method(GenTypeBasic(field.value.type));
GenReceiver(struct_def, code_ptr);
code += " Mutate" + namer_.Function(field);
code +=
"(n " + GenTypeGet(field.value.type) + ") bool {\n\treturn " + setter;
code += "(rcv._tab.Pos+flatbuffers.UOffsetT(";
code += NumToString(field.value.offset) + "), ";
code += CastToBaseType(field.value.type, "n") + ")\n}\n\n";
}
// Mutate the value of a table's scalar.
void MutateScalarFieldOfTable(const StructDef &struct_def,
const FieldDef &field, std::string *code_ptr) {
std::string &code = *code_ptr;
std::string setter = "rcv._tab.Mutate" +
namer_.Method(GenTypeBasic(field.value.type)) + "Slot";
GenReceiver(struct_def, code_ptr);
code += " Mutate" + namer_.Function(field);
code += "(n " + GenTypeGet(field.value.type) + ") bool {\n\treturn ";
code += setter + "(" + NumToString(field.value.offset) + ", ";
code += CastToBaseType(field.value.type, "n") + ")\n";
code += "}\n\n";
}
// Mutate an element of a vector of scalars.
void MutateElementOfVectorOfNonStruct(const StructDef &struct_def,
const FieldDef &field,
std::string *code_ptr) {
std::string &code = *code_ptr;
auto vectortype = field.value.type.VectorType();
std::string setter =
"rcv._tab.Mutate" + namer_.Method(GenTypeBasic(vectortype));
GenReceiver(struct_def, code_ptr);
code += " Mutate" + namer_.Function(field);
code += "(j int, n " + TypeName(field) + ") bool ";
code += OffsetPrefix(field);
code += "\t\ta := rcv._tab.Vector(o)\n";
code += "\t\treturn " + setter + "(";
code += "a+flatbuffers.UOffsetT(j*";
code += NumToString(InlineSize(vectortype)) + "), ";
code += CastToBaseType(vectortype, "n") + ")\n";
code += "\t}\n";
code += "\treturn false\n";
code += "}\n\n";
}
// Generate a struct field setter, conditioned on its child type(s).
void GenStructMutator(const StructDef &struct_def, const FieldDef &field,
std::string *code_ptr) {
GenComment(field.doc_comment, code_ptr, nullptr, "");
if (IsScalar(field.value.type.base_type)) {
if (struct_def.fixed) {
MutateScalarFieldOfStruct(struct_def, field, code_ptr);
} else {
MutateScalarFieldOfTable(struct_def, field, code_ptr);
}
} else if (IsVector(field.value.type)) {
if (IsScalar(field.value.type.element)) {
MutateElementOfVectorOfNonStruct(struct_def, field, code_ptr);
}
}
}
// Generate table constructors, conditioned on its members' types.
void GenTableBuilders(const StructDef &struct_def, std::string *code_ptr) {
GetStartOfTable(struct_def, code_ptr);
for (auto it = struct_def.fields.vec.begin();
it != struct_def.fields.vec.end(); ++it) {
auto &field = **it;
if (field.deprecated) continue;
auto offset = it - struct_def.fields.vec.begin();
BuildFieldOfTable(struct_def, field, offset, code_ptr);
if (IsVector(field.value.type)) {
BuildVectorOfTable(struct_def, field, code_ptr);
}
}
GetEndOffsetOnTable(struct_def, code_ptr);
}
// Generate struct or table methods.
void GenStruct(const StructDef &struct_def, std::string *code_ptr) {
if (struct_def.generated) return;
cur_name_space_ = struct_def.defined_namespace;
GenComment(struct_def.doc_comment, code_ptr, nullptr);
if (parser_.opts.generate_object_based_api) {
GenNativeStruct(struct_def, code_ptr);
}
BeginClass(struct_def, code_ptr);
if (!struct_def.fixed) {
// Generate a special accessor for the table that has been declared as
// the root type.
NewRootTypeFromBuffer(struct_def, code_ptr);
}
// Generate the Init method that sets the field in a pre-existing
// accessor object. This is to allow object reuse.
InitializeExisting(struct_def, code_ptr);
// Generate _tab accessor
GenTableAccessor(struct_def, code_ptr);
// Generate struct fields accessors
for (auto it = struct_def.fields.vec.begin();
it != struct_def.fields.vec.end(); ++it) {
auto &field = **it;
if (field.deprecated) continue;
GenStructAccessor(struct_def, field, code_ptr);
GenStructMutator(struct_def, field, code_ptr);
}
// Generate builders
if (struct_def.fixed) {
// create a struct constructor function
GenStructBuilder(struct_def, code_ptr);
} else {
// Create a set of functions that allow table construction.
GenTableBuilders(struct_def, code_ptr);
}
}
void GenNativeStruct(const StructDef &struct_def, std::string *code_ptr) {
std::string &code = *code_ptr;
code += "type " + NativeName(struct_def) + " struct {\n";
for (auto it = struct_def.fields.vec.begin();
it != struct_def.fields.vec.end(); ++it) {
const FieldDef &field = **it;
if (field.deprecated) continue;
if (IsScalar(field.value.type.base_type) &&
field.value.type.enum_def != nullptr &&
field.value.type.enum_def->is_union)
continue;
code += "\t" + namer_.Field(field) + " ";
if (field.IsScalarOptional()) { code += "*"; }
code += NativeType(field.value.type) + " `json:\"" + field.name + "\"`" +
"\n";
}
code += "}\n\n";
if (!struct_def.fixed) {
GenNativeTablePack(struct_def, code_ptr);
GenNativeTableUnPack(struct_def, code_ptr);
} else {
GenNativeStructPack(struct_def, code_ptr);
GenNativeStructUnPack(struct_def, code_ptr);
}
}
void GenNativeUnion(const EnumDef &enum_def, std::string *code_ptr) {
std::string &code = *code_ptr;
code += "type " + NativeName(enum_def) + " struct {\n";
code += "\tType " + namer_.Type(enum_def) + "\n";
code += "\tValue interface{}\n";
code += "}\n\n";
}
void GenNativeUnionPack(const EnumDef &enum_def, std::string *code_ptr) {
std::string &code = *code_ptr;
code += "func (t *" + NativeName(enum_def) +
") Pack(builder *flatbuffers.Builder) flatbuffers.UOffsetT {\n";
code += "\tif t == nil {\n\t\treturn 0\n\t}\n";
code += "\tswitch t.Type {\n";
for (auto it2 = enum_def.Vals().begin(); it2 != enum_def.Vals().end();
++it2) {
const EnumVal &ev = **it2;
if (ev.IsZero()) continue;
code += "\tcase " + namer_.EnumVariant(enum_def, ev) + ":\n";
code += "\t\treturn t.Value.(" + NativeType(ev.union_type) +
").Pack(builder)\n";
}
code += "\t}\n";
code += "\treturn 0\n";
code += "}\n\n";
}
void GenNativeUnionUnPack(const EnumDef &enum_def, std::string *code_ptr) {
std::string &code = *code_ptr;
code += "func (rcv " + namer_.Type(enum_def) +
") UnPack(table flatbuffers.Table) *" + NativeName(enum_def) +
" {\n";
code += "\tswitch rcv {\n";
for (auto it2 = enum_def.Vals().begin(); it2 != enum_def.Vals().end();
++it2) {
const EnumVal &ev = **it2;
if (ev.IsZero()) continue;
code += "\tcase " + namer_.EnumVariant(enum_def, ev) + ":\n";
code += "\t\tx := " + ev.union_type.struct_def->name + "{_tab: table}\n";
code += "\t\treturn &" +
WrapInNameSpaceAndTrack(enum_def.defined_namespace,
NativeName(enum_def)) +
"{ Type: " + namer_.EnumVariant(enum_def, ev) +
", Value: x.UnPack() }\n";
}
code += "\t}\n";
code += "\treturn nil\n";
code += "}\n\n";
}
void GenNativeTablePack(const StructDef &struct_def, std::string *code_ptr) {
std::string &code = *code_ptr;
const std::string struct_type = namer_.Type(struct_def);
code += "func (t *" + NativeName(struct_def) +
") Pack(builder *flatbuffers.Builder) flatbuffers.UOffsetT {\n";
code += "\tif t == nil { return 0 }\n";
for (auto it = struct_def.fields.vec.begin();
it != struct_def.fields.vec.end(); ++it) {
const FieldDef &field = **it;
if (field.deprecated) continue;
if (IsScalar(field.value.type.base_type)) continue;
const std::string field_field = namer_.Field(field);
const std::string field_var = namer_.Variable(field);
const std::string offset = field_var + "Offset";
if (IsString(field.value.type)) {
code +=
"\t" + offset + " := builder.CreateString(t." + field_field + ")\n";
} else if (IsVector(field.value.type) &&
field.value.type.element == BASE_TYPE_UCHAR &&
field.value.type.enum_def == nullptr) {
code += "\t" + offset + " := flatbuffers.UOffsetT(0)\n";
code += "\tif t." + field_field + " != nil {\n";
code += "\t\t" + offset + " = builder.CreateByteString(t." +
field_field + ")\n";
code += "\t}\n";
} else if (IsVector(field.value.type)) {
code += "\t" + offset + " := flatbuffers.UOffsetT(0)\n";
code += "\tif t." + field_field + " != nil {\n";
std::string length = field_var + "Length";
std::string offsets = field_var + "Offsets";
code += "\t\t" + length + " := len(t." + field_field + ")\n";
if (field.value.type.element == BASE_TYPE_STRING) {
code += "\t\t" + offsets + " := make([]flatbuffers.UOffsetT, " +
length + ")\n";
code += "\t\tfor j := 0; j < " + length + "; j++ {\n";
code += "\t\t\t" + offsets + "[j] = builder.CreateString(t." +
field_field + "[j])\n";
code += "\t\t}\n";
} else if (field.value.type.element == BASE_TYPE_STRUCT &&
!field.value.type.struct_def->fixed) {
code += "\t\t" + offsets + " := make([]flatbuffers.UOffsetT, " +
length + ")\n";
code += "\t\tfor j := 0; j < " + length + "; j++ {\n";
code += "\t\t\t" + offsets + "[j] = t." + field_field +
"[j].Pack(builder)\n";
code += "\t\t}\n";
}
code += "\t\t" + struct_type + "Start" + namer_.Function(field) +
"Vector(builder, " + length + ")\n";
code += "\t\tfor j := " + length + " - 1; j >= 0; j-- {\n";
if (IsScalar(field.value.type.element)) {
code += "\t\t\tbuilder.Prepend" +
namer_.Method(GenTypeBasic(field.value.type.VectorType())) +
"(" +
CastToBaseType(field.value.type.VectorType(),
"t." + field_field + "[j]") +
")\n";
} else if (field.value.type.element == BASE_TYPE_STRUCT &&
field.value.type.struct_def->fixed) {
code += "\t\t\tt." + field_field + "[j].Pack(builder)\n";
} else {
code += "\t\t\tbuilder.PrependUOffsetT(" + offsets + "[j])\n";
}
code += "\t\t}\n";
code += "\t\t" + offset + " = builder.EndVector(" + length + ")\n";
code += "\t}\n";
} else if (field.value.type.base_type == BASE_TYPE_STRUCT) {
if (field.value.type.struct_def->fixed) continue;
code += "\t" + offset + " := t." + field_field + ".Pack(builder)\n";
} else if (field.value.type.base_type == BASE_TYPE_UNION) {
code += "\t" + offset + " := t." + field_field + ".Pack(builder)\n";
code += "\t\n";
} else {
FLATBUFFERS_ASSERT(0);
}
}
code += "\t" + struct_type + "Start(builder)\n";
for (auto it = struct_def.fields.vec.begin();
it != struct_def.fields.vec.end(); ++it) {
const FieldDef &field = **it;