1/*
2 * Copyright 2015 Google Inc. All rights reserved.
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#include "flatbuffers/reflection.h"
18
19#include "flatbuffers/util.h"
20
21// Helper functionality for reflection.
22
23namespace flatbuffers {
24
25int64_t GetAnyValueI(reflection::BaseType type, const uint8_t *data) {
26 // clang-format off
27 #define FLATBUFFERS_GET(T) static_cast<int64_t>(ReadScalar<T>(data))
28 switch (type) {
29 case reflection::UType:
30 case reflection::Bool:
31 case reflection::UByte: return FLATBUFFERS_GET(uint8_t);
32 case reflection::Byte: return FLATBUFFERS_GET(int8_t);
33 case reflection::Short: return FLATBUFFERS_GET(int16_t);
34 case reflection::UShort: return FLATBUFFERS_GET(uint16_t);
35 case reflection::Int: return FLATBUFFERS_GET(int32_t);
36 case reflection::UInt: return FLATBUFFERS_GET(uint32_t);
37 case reflection::Long: return FLATBUFFERS_GET(int64_t);
38 case reflection::ULong: return FLATBUFFERS_GET(uint64_t);
39 case reflection::Float: return FLATBUFFERS_GET(float);
40 case reflection::Double: return FLATBUFFERS_GET(double);
41 case reflection::String: {
42 auto s = reinterpret_cast<const String *>(ReadScalar<uoffset_t>(data) +
43 data);
44 return s ? StringToInt(s->c_str()) : 0;
45 }
46 default: return 0; // Tables & vectors do not make sense.
47 }
48 #undef FLATBUFFERS_GET
49 // clang-format on
50}
51
52double GetAnyValueF(reflection::BaseType type, const uint8_t *data) {
53 switch (type) {
54 case reflection::Float: return static_cast<double>(ReadScalar<float>(data));
55 case reflection::Double: return ReadScalar<double>(data);
56 case reflection::String: {
57 auto s =
58 reinterpret_cast<const String *>(ReadScalar<uoffset_t>(data) + data);
59 if (s) {
60 double d;
61 StringToNumber(s->c_str(), &d);
62 return d;
63 } else {
64 return 0.0;
65 }
66 }
67 default: return static_cast<double>(GetAnyValueI(type, data));
68 }
69}
70
71std::string GetAnyValueS(reflection::BaseType type, const uint8_t *data,
72 const reflection::Schema *schema, int type_index) {
73 switch (type) {
74 case reflection::Float:
75 case reflection::Double: return NumToString(GetAnyValueF(type, data));
76 case reflection::String: {
77 auto s =
78 reinterpret_cast<const String *>(ReadScalar<uoffset_t>(data) + data);
79 return s ? s->c_str() : "";
80 }
81 case reflection::Obj:
82 if (schema) {
83 // Convert the table to a string. This is mostly for debugging purposes,
84 // and does NOT promise to be JSON compliant.
85 // Also prefixes the type.
86 auto &objectdef = *schema->objects()->Get(type_index);
87 auto s = objectdef.name()->str();
88 if (objectdef.is_struct()) {
89 s += "(struct)"; // TODO: implement this as well.
90 } else {
91 auto table_field = reinterpret_cast<const Table *>(
92 ReadScalar<uoffset_t>(data) + data);
93 s += " { ";
94 auto fielddefs = objectdef.fields();
95 for (auto it = fielddefs->begin(); it != fielddefs->end(); ++it) {
96 auto &fielddef = **it;
97 if (!table_field->CheckField(fielddef.offset())) continue;
98 auto val = GetAnyFieldS(*table_field, fielddef, schema);
99 if (fielddef.type()->base_type() == reflection::String) {
100 std::string esc;
101 flatbuffers::EscapeString(val.c_str(), val.length(), &esc, true,
102 false);
103 val = esc;
104 }
105 s += fielddef.name()->str();
106 s += ": ";
107 s += val;
108 s += ", ";
109 }
110 s += "}";
111 }
112 return s;
113 } else {
114 return "(table)";
115 }
116 case reflection::Vector:
117 return "[(elements)]"; // TODO: implement this as well.
118 case reflection::Union: return "(union)"; // TODO: implement this as well.
119 default: return NumToString(GetAnyValueI(type, data));
120 }
121}
122
123void SetAnyValueI(reflection::BaseType type, uint8_t *data, int64_t val) {
124 // clang-format off
125 #define FLATBUFFERS_SET(T) WriteScalar(data, static_cast<T>(val))
126 switch (type) {
127 case reflection::UType:
128 case reflection::Bool:
129 case reflection::UByte: FLATBUFFERS_SET(uint8_t ); break;
130 case reflection::Byte: FLATBUFFERS_SET(int8_t ); break;
131 case reflection::Short: FLATBUFFERS_SET(int16_t ); break;
132 case reflection::UShort: FLATBUFFERS_SET(uint16_t); break;
133 case reflection::Int: FLATBUFFERS_SET(int32_t ); break;
134 case reflection::UInt: FLATBUFFERS_SET(uint32_t); break;
135 case reflection::Long: FLATBUFFERS_SET(int64_t ); break;
136 case reflection::ULong: FLATBUFFERS_SET(uint64_t); break;
137 case reflection::Float: FLATBUFFERS_SET(float ); break;
138 case reflection::Double: FLATBUFFERS_SET(double ); break;
139 // TODO: support strings
140 default: break;
141 }
142 #undef FLATBUFFERS_SET
143 // clang-format on
144}
145
146void SetAnyValueF(reflection::BaseType type, uint8_t *data, double val) {
147 switch (type) {
148 case reflection::Float: WriteScalar(data, static_cast<float>(val)); break;
149 case reflection::Double: WriteScalar(data, val); break;
150 // TODO: support strings.
151 default: SetAnyValueI(type, data, static_cast<int64_t>(val)); break;
152 }
153}
154
155void SetAnyValueS(reflection::BaseType type, uint8_t *data, const char *val) {
156 switch (type) {
157 case reflection::Float:
158 case reflection::Double: {
159 double d;
160 StringToNumber(val, &d);
161 SetAnyValueF(type, data, d);
162 break;
163 }
164 // TODO: support strings.
165 default: SetAnyValueI(type, data, StringToInt(val)); break;
166 }
167}
168
169// Resize a FlatBuffer in-place by iterating through all offsets in the buffer
170// and adjusting them by "delta" if they straddle the start offset.
171// Once that is done, bytes can now be inserted/deleted safely.
172// "delta" may be negative (shrinking).
173// Unless "delta" is a multiple of the largest alignment, you'll create a small
174// amount of garbage space in the buffer (usually 0..7 bytes).
175// If your FlatBuffer's root table is not the schema's root table, you should
176// pass in your root_table type as well.
177class ResizeContext {
178 public:
179 ResizeContext(const reflection::Schema &schema, uoffset_t start, int delta,
180 std::vector<uint8_t> *flatbuf,
181 const reflection::Object *root_table = nullptr)
182 : schema_(schema),
183 startptr_(flatbuf->data() + start),
184 delta_(delta),
185 buf_(*flatbuf),
186 dag_check_(flatbuf->size() / sizeof(uoffset_t), false) {
187 auto mask = static_cast<int>(sizeof(largest_scalar_t) - 1);
188 delta_ = (delta_ + mask) & ~mask;
189 if (!delta_) return; // We can't shrink by less than largest_scalar_t.
190 // Now change all the offsets by delta_.
191 auto root = GetAnyRoot(buf_.data());
192 Straddle<uoffset_t, 1>(buf_.data(), root, buf_.data());
193 ResizeTable(root_table ? *root_table : *schema.root_table(), root);
194 // We can now add or remove bytes at start.
195 if (delta_ > 0)
196 buf_.insert(buf_.begin() + start, delta_, 0);
197 else
198 buf_.erase(buf_.begin() + start + delta_, buf_.begin() + start);
199 }
200
201 // Check if the range between first (lower address) and second straddles
202 // the insertion point. If it does, change the offset at offsetloc (of
203 // type T, with direction D).
204 template<typename T, int D>
205 void Straddle(const void *first, const void *second, void *offsetloc) {
206 if (first <= startptr_ && second >= startptr_) {
207 WriteScalar<T>(offsetloc, ReadScalar<T>(offsetloc) + delta_ * D);
208 DagCheck(offsetloc) = true;
209 }
210 }
211
212 // This returns a boolean that records if the corresponding offset location
213 // has been modified already. If so, we can't even read the corresponding
214 // offset, since it is pointing to a location that is illegal until the
215 // resize actually happens.
216 // This must be checked for every offset, since we can't know which offsets
217 // will straddle and which won't.
218 uint8_t &DagCheck(const void *offsetloc) {
219 auto dag_idx = reinterpret_cast<const uoffset_t *>(offsetloc) -
220 reinterpret_cast<const uoffset_t *>(buf_.data());
221 return dag_check_[dag_idx];
222 }
223
224 void ResizeTable(const reflection::Object &objectdef, Table *table) {
225 if (DagCheck(table)) return; // Table already visited.
226 auto vtable = table->GetVTable();
227 // Early out: since all fields inside the table must point forwards in
228 // memory, if the insertion point is before the table we can stop here.
229 auto tableloc = reinterpret_cast<uint8_t *>(table);
230 if (startptr_ <= tableloc) {
231 // Check if insertion point is between the table and a vtable that
232 // precedes it. This can't happen in current construction code, but check
233 // just in case we ever change the way flatbuffers are built.
234 Straddle<soffset_t, -1>(vtable, table, table);
235 } else {
236 // Check each field.
237 auto fielddefs = objectdef.fields();
238 for (auto it = fielddefs->begin(); it != fielddefs->end(); ++it) {
239 auto &fielddef = **it;
240 auto base_type = fielddef.type()->base_type();
241 // Ignore scalars.
242 if (base_type <= reflection::Double) continue;
243 // Ignore fields that are not stored.
244 auto offset = table->GetOptionalFieldOffset(fielddef.offset());
245 if (!offset) continue;
246 // Ignore structs.
247 auto subobjectdef =
248 base_type == reflection::Obj
249 ? schema_.objects()->Get(fielddef.type()->index())
250 : nullptr;
251 if (subobjectdef && subobjectdef->is_struct()) continue;
252 // Get this fields' offset, and read it if safe.
253 auto offsetloc = tableloc + offset;
254 if (DagCheck(offsetloc)) continue; // This offset already visited.
255 auto ref = offsetloc + ReadScalar<uoffset_t>(offsetloc);
256 Straddle<uoffset_t, 1>(offsetloc, ref, offsetloc);
257 // Recurse.
258 switch (base_type) {
259 case reflection::Obj: {
260 ResizeTable(*subobjectdef, reinterpret_cast<Table *>(ref));
261 break;
262 }
263 case reflection::Vector: {
264 auto elem_type = fielddef.type()->element();
265 if (elem_type != reflection::Obj && elem_type != reflection::String)
266 break;
267 auto vec = reinterpret_cast<Vector<uoffset_t> *>(ref);
268 auto elemobjectdef =
269 elem_type == reflection::Obj
270 ? schema_.objects()->Get(fielddef.type()->index())
271 : nullptr;
272 if (elemobjectdef && elemobjectdef->is_struct()) break;
273 for (uoffset_t i = 0; i < vec->size(); i++) {
274 auto loc = vec->Data() + i * sizeof(uoffset_t);
275 if (DagCheck(loc)) continue; // This offset already visited.
276 auto dest = loc + vec->Get(i);
277 Straddle<uoffset_t, 1>(loc, dest, loc);
278 if (elemobjectdef)
279 ResizeTable(*elemobjectdef, reinterpret_cast<Table *>(dest));
280 }
281 break;
282 }
283 case reflection::Union: {
284 ResizeTable(GetUnionType(schema_, objectdef, fielddef, *table),
285 reinterpret_cast<Table *>(ref));
286 break;
287 }
288 case reflection::String: break;
289 default: FLATBUFFERS_ASSERT(false);
290 }
291 }
292 // Check if the vtable offset points beyond the insertion point.
293 // Must do this last, since GetOptionalFieldOffset above still reads
294 // this value.
295 Straddle<soffset_t, -1>(table, vtable, table);
296 }
297 }
298
299 private:
300 const reflection::Schema &schema_;
301 uint8_t *startptr_;
302 int delta_;
303 std::vector<uint8_t> &buf_;
304 std::vector<uint8_t> dag_check_;
305};
306
307void SetString(const reflection::Schema &schema, const std::string &val,
308 const String *str, std::vector<uint8_t> *flatbuf,
309 const reflection::Object *root_table) {
310 auto delta = static_cast<int>(val.size()) - static_cast<int>(str->size());
311 auto str_start = static_cast<uoffset_t>(
312 reinterpret_cast<const uint8_t *>(str) - flatbuf->data());
313 auto start = str_start + static_cast<uoffset_t>(sizeof(uoffset_t));
314 if (delta) {
315 // Clear the old string, since we don't want parts of it remaining.
316 memset(flatbuf->data() + start, 0, str->size());
317 // Different size, we must expand (or contract).
318 ResizeContext(schema, start, delta, flatbuf, root_table);
319 // Set the new length.
320 WriteScalar(flatbuf->data() + str_start,
321 static_cast<uoffset_t>(val.size()));
322 }
323 // Copy new data. Safe because we created the right amount of space.
324 memcpy(flatbuf->data() + start, val.c_str(), val.size() + 1);
325}
326
327uint8_t *ResizeAnyVector(const reflection::Schema &schema, uoffset_t newsize,
328 const VectorOfAny *vec, uoffset_t num_elems,
329 uoffset_t elem_size, std::vector<uint8_t> *flatbuf,
330 const reflection::Object *root_table) {
331 auto delta_elem = static_cast<int>(newsize) - static_cast<int>(num_elems);
332 auto delta_bytes = delta_elem * static_cast<int>(elem_size);
333 auto vec_start = reinterpret_cast<const uint8_t *>(vec) - flatbuf->data();
334 auto start = static_cast<uoffset_t>(vec_start) +
335 static_cast<uoffset_t>(sizeof(uoffset_t)) +
336 elem_size * num_elems;
337 if (delta_bytes) {
338 if (delta_elem < 0) {
339 // Clear elements we're throwing away, since some might remain in the
340 // buffer.
341 auto size_clear = -delta_elem * elem_size;
342 memset(flatbuf->data() + start - size_clear, 0, size_clear);
343 }
344 ResizeContext(schema, start, delta_bytes, flatbuf, root_table);
345 WriteScalar(flatbuf->data() + vec_start, newsize); // Length field.
346 // Set new elements to 0.. this can be overwritten by the caller.
347 if (delta_elem > 0) {
348 memset(flatbuf->data() + start, 0,
349 static_cast<size_t>(delta_elem) * elem_size);
350 }
351 }
352 return flatbuf->data() + start;
353}
354
355const uint8_t *AddFlatBuffer(std::vector<uint8_t> &flatbuf,
356 const uint8_t *newbuf, size_t newlen) {
357 // Align to sizeof(uoffset_t) past sizeof(largest_scalar_t) since we're
358 // going to chop off the root offset.
359 while ((flatbuf.size() & (sizeof(uoffset_t) - 1)) ||
360 !(flatbuf.size() & (sizeof(largest_scalar_t) - 1))) {
361 flatbuf.push_back(0);
362 }
363 auto insertion_point = static_cast<uoffset_t>(flatbuf.size());
364 // Insert the entire FlatBuffer minus the root pointer.
365 flatbuf.insert(flatbuf.end(), newbuf + sizeof(uoffset_t), newbuf + newlen);
366 auto root_offset = ReadScalar<uoffset_t>(newbuf) - sizeof(uoffset_t);
367 return flatbuf.data() + insertion_point + root_offset;
368}
369
370void CopyInline(FlatBufferBuilder &fbb, const reflection::Field &fielddef,
371 const Table &table, size_t align, size_t size) {
372 fbb.Align(align);
373 fbb.PushBytes(table.GetStruct<const uint8_t *>(fielddef.offset()), size);
374 fbb.TrackField(fielddef.offset(), fbb.GetSize());
375}
376
377Offset<const Table *> CopyTable(FlatBufferBuilder &fbb,
378 const reflection::Schema &schema,
379 const reflection::Object &objectdef,
380 const Table &table, bool use_string_pooling) {
381 // Before we can construct the table, we have to first generate any
382 // subobjects, and collect their offsets.
383 std::vector<uoffset_t> offsets;
384 auto fielddefs = objectdef.fields();
385 for (auto it = fielddefs->begin(); it != fielddefs->end(); ++it) {
386 auto &fielddef = **it;
387 // Skip if field is not present in the source.
388 if (!table.CheckField(fielddef.offset())) continue;
389 uoffset_t offset = 0;
390 switch (fielddef.type()->base_type()) {
391 case reflection::String: {
392 offset = use_string_pooling
393 ? fbb.CreateSharedString(GetFieldS(table, fielddef)).o
394 : fbb.CreateString(GetFieldS(table, fielddef)).o;
395 break;
396 }
397 case reflection::Obj: {
398 auto &subobjectdef = *schema.objects()->Get(fielddef.type()->index());
399 if (!subobjectdef.is_struct()) {
400 offset = CopyTable(fbb, schema, subobjectdef,
401 *GetFieldT(table, fielddef), use_string_pooling)
402 .o;
403 }
404 break;
405 }
406 case reflection::Union: {
407 auto &subobjectdef = GetUnionType(schema, objectdef, fielddef, table);
408 offset = CopyTable(fbb, schema, subobjectdef,
409 *GetFieldT(table, fielddef), use_string_pooling)
410 .o;
411 break;
412 }
413 case reflection::Vector: {
414 auto vec =
415 table.GetPointer<const Vector<Offset<Table>> *>(fielddef.offset());
416 auto element_base_type = fielddef.type()->element();
417 auto elemobjectdef =
418 element_base_type == reflection::Obj
419 ? schema.objects()->Get(fielddef.type()->index())
420 : nullptr;
421 switch (element_base_type) {
422 case reflection::String: {
423 std::vector<Offset<const String *>> elements(vec->size());
424 auto vec_s = reinterpret_cast<const Vector<Offset<String>> *>(vec);
425 for (uoffset_t i = 0; i < vec_s->size(); i++) {
426 elements[i] = use_string_pooling
427 ? fbb.CreateSharedString(vec_s->Get(i)).o
428 : fbb.CreateString(vec_s->Get(i)).o;
429 }
430 offset = fbb.CreateVector(elements).o;
431 break;
432 }
433 case reflection::Obj: {
434 if (!elemobjectdef->is_struct()) {
435 std::vector<Offset<const Table *>> elements(vec->size());
436 for (uoffset_t i = 0; i < vec->size(); i++) {
437 elements[i] = CopyTable(fbb, schema, *elemobjectdef,
438 *vec->Get(i), use_string_pooling);
439 }
440 offset = fbb.CreateVector(elements).o;
441 break;
442 }
443 }
444 FLATBUFFERS_FALLTHROUGH(); // fall thru
445 default: { // Scalars and structs.
446 auto element_size = GetTypeSize(element_base_type);
447 if (elemobjectdef && elemobjectdef->is_struct())
448 element_size = elemobjectdef->bytesize();
449 fbb.StartVector(vec->size(), element_size);
450 fbb.PushBytes(vec->Data(), element_size * vec->size());
451 offset = fbb.EndVector(vec->size());
452 break;
453 }
454 }
455 break;
456 }
457 default: // Scalars.
458 break;
459 }
460 if (offset) { offsets.push_back(offset); }
461 }
462 // Now we can build the actual table from either offsets or scalar data.
463 auto start = objectdef.is_struct() ? fbb.StartStruct(objectdef.minalign())
464 : fbb.StartTable();
465 size_t offset_idx = 0;
466 for (auto it = fielddefs->begin(); it != fielddefs->end(); ++it) {
467 auto &fielddef = **it;
468 if (!table.CheckField(fielddef.offset())) continue;
469 auto base_type = fielddef.type()->base_type();
470 switch (base_type) {
471 case reflection::Obj: {
472 auto &subobjectdef = *schema.objects()->Get(fielddef.type()->index());
473 if (subobjectdef.is_struct()) {
474 CopyInline(fbb, fielddef, table, subobjectdef.minalign(),
475 subobjectdef.bytesize());
476 break;
477 }
478 }
479 FLATBUFFERS_FALLTHROUGH(); // fall thru
480 case reflection::Union:
481 case reflection::String:
482 case reflection::Vector:
483 fbb.AddOffset(fielddef.offset(), Offset<void>(offsets[offset_idx++]));
484 break;
485 default: { // Scalars.
486 auto size = GetTypeSize(base_type);
487 CopyInline(fbb, fielddef, table, size, size);
488 break;
489 }
490 }
491 }
492 FLATBUFFERS_ASSERT(offset_idx == offsets.size());
493 if (objectdef.is_struct()) {
494 fbb.ClearOffsets();
495 return fbb.EndStruct();
496 } else {
497 return fbb.EndTable(start);
498 }
499}
500
501bool VerifyStruct(flatbuffers::Verifier &v,
502 const flatbuffers::Table &parent_table,
503 voffset_t field_offset, const reflection::Object &obj,
504 bool required) {
505 auto offset = parent_table.GetOptionalFieldOffset(field_offset);
506 if (required && !offset) { return false; }
507
508 return !offset ||
509 v.VerifyFieldStruct(reinterpret_cast<const uint8_t *>(&parent_table),
510 offset, obj.bytesize(), obj.minalign());
511}
512
513bool VerifyVectorOfStructs(flatbuffers::Verifier &v,
514 const flatbuffers::Table &parent_table,
515 voffset_t field_offset,
516 const reflection::Object &obj, bool required) {
517 auto p = parent_table.GetPointer<const uint8_t *>(field_offset);
518 if (required && !p) { return false; }
519
520 return !p || v.VerifyVectorOrString(p, obj.bytesize());
521}
522
523// forward declare to resolve cyclic deps between VerifyObject and VerifyVector
524bool VerifyObject(flatbuffers::Verifier &v, const reflection::Schema &schema,
525 const reflection::Object &obj,
526 const flatbuffers::Table *table, bool required);
527
528bool VerifyUnion(flatbuffers::Verifier &v, const reflection::Schema &schema,
529 uint8_t utype, const uint8_t *elem,
530 const reflection::Field &union_field) {
531 if (!utype) return true; // Not present.
532 auto fb_enum = schema.enums()->Get(union_field.type()->index());
533 if (utype >= fb_enum->values()->size()) return false;
534 auto elem_type = fb_enum->values()->Get(utype)->union_type();
535 switch (elem_type->base_type()) {
536 case reflection::Obj: {
537 auto elem_obj = schema.objects()->Get(elem_type->index());
538 if (elem_obj->is_struct()) {
539 return v.VerifyFromPointer(elem, elem_obj->bytesize());
540 } else {
541 return VerifyObject(v, schema, *elem_obj,
542 reinterpret_cast<const flatbuffers::Table *>(elem),
543 true);
544 }
545 }
546 case reflection::String:
547 return v.VerifyString(
548 reinterpret_cast<const flatbuffers::String *>(elem));
549 default: return false;
550 }
551}
552
553bool VerifyVector(flatbuffers::Verifier &v, const reflection::Schema &schema,
554 const flatbuffers::Table &table,
555 const reflection::Field &vec_field) {
556 FLATBUFFERS_ASSERT(vec_field.type()->base_type() == reflection::Vector);
557 if (!table.VerifyField<uoffset_t>(v, vec_field.offset(), sizeof(uoffset_t)))
558 return false;
559
560 switch (vec_field.type()->element()) {
561 case reflection::UType:
562 return v.VerifyVector(flatbuffers::GetFieldV<uint8_t>(table, vec_field));
563 case reflection::Bool:
564 case reflection::Byte:
565 case reflection::UByte:
566 return v.VerifyVector(flatbuffers::GetFieldV<int8_t>(table, vec_field));
567 case reflection::Short:
568 case reflection::UShort:
569 return v.VerifyVector(flatbuffers::GetFieldV<int16_t>(table, vec_field));
570 case reflection::Int:
571 case reflection::UInt:
572 return v.VerifyVector(flatbuffers::GetFieldV<int32_t>(table, vec_field));
573 case reflection::Long:
574 case reflection::ULong:
575 return v.VerifyVector(flatbuffers::GetFieldV<int64_t>(table, vec_field));
576 case reflection::Float:
577 return v.VerifyVector(flatbuffers::GetFieldV<float>(table, vec_field));
578 case reflection::Double:
579 return v.VerifyVector(flatbuffers::GetFieldV<double>(table, vec_field));
580 case reflection::String: {
581 auto vec_string =
582 flatbuffers::GetFieldV<flatbuffers::Offset<flatbuffers::String>>(
583 table, vec_field);
584 if (v.VerifyVector(vec_string) && v.VerifyVectorOfStrings(vec_string)) {
585 return true;
586 } else {
587 return false;
588 }
589 }
590 case reflection::Obj: {
591 auto obj = schema.objects()->Get(vec_field.type()->index());
592 if (obj->is_struct()) {
593 return VerifyVectorOfStructs(v, table, vec_field.offset(), *obj,
594 vec_field.required());
595 } else {
596 auto vec =
597 flatbuffers::GetFieldV<flatbuffers::Offset<flatbuffers::Table>>(
598 table, vec_field);
599 if (!v.VerifyVector(vec)) return false;
600 if (!vec) return true;
601 for (uoffset_t j = 0; j < vec->size(); j++) {
602 if (!VerifyObject(v, schema, *obj, vec->Get(j), true)) {
603 return false;
604 }
605 }
606 return true;
607 }
608 }
609 case reflection::Union: {
610 auto vec = flatbuffers::GetFieldV<flatbuffers::Offset<uint8_t>>(
611 table, vec_field);
612 if (!v.VerifyVector(vec)) return false;
613 if (!vec) return true;
614 auto type_vec = table.GetPointer<Vector<uint8_t> *>(vec_field.offset() -
615 sizeof(voffset_t));
616 if (!v.VerifyVector(type_vec)) return false;
617 for (uoffset_t j = 0; j < vec->size(); j++) {
618 // get union type from the prev field
619 auto utype = type_vec->Get(j);
620 auto elem = vec->Get(j);
621 if (!VerifyUnion(v, schema, utype, elem, vec_field)) return false;
622 }
623 return true;
624 }
625 case reflection::Vector:
626 case reflection::None:
627 default: FLATBUFFERS_ASSERT(false); return false;
628 }
629}
630
631bool VerifyObject(flatbuffers::Verifier &v, const reflection::Schema &schema,
632 const reflection::Object &obj,
633 const flatbuffers::Table *table, bool required) {
634 if (!table) return !required;
635 if (!table->VerifyTableStart(v)) return false;
636 for (uoffset_t i = 0; i < obj.fields()->size(); i++) {
637 auto field_def = obj.fields()->Get(i);
638 switch (field_def->type()->base_type()) {
639 case reflection::None: FLATBUFFERS_ASSERT(false); break;
640 case reflection::UType:
641 if (!table->VerifyField<uint8_t>(v, field_def->offset(),
642 sizeof(uint8_t)))
643 return false;
644 break;
645 case reflection::Bool:
646 case reflection::Byte:
647 case reflection::UByte:
648 if (!table->VerifyField<int8_t>(v, field_def->offset(), sizeof(int8_t)))
649 return false;
650 break;
651 case reflection::Short:
652 case reflection::UShort:
653 if (!table->VerifyField<int16_t>(v, field_def->offset(),
654 sizeof(int16_t)))
655 return false;
656 break;
657 case reflection::Int:
658 case reflection::UInt:
659 if (!table->VerifyField<int32_t>(v, field_def->offset(),
660 sizeof(int32_t)))
661 return false;
662 break;
663 case reflection::Long:
664 case reflection::ULong:
665 if (!table->VerifyField<int64_t>(v, field_def->offset(),
666 sizeof(int64_t)))
667 return false;
668 break;
669 case reflection::Float:
670 if (!table->VerifyField<float>(v, field_def->offset(), sizeof(float)))
671 return false;
672 break;
673 case reflection::Double:
674 if (!table->VerifyField<double>(v, field_def->offset(), sizeof(double)))
675 return false;
676 break;
677 case reflection::String:
678 if (!table->VerifyField<uoffset_t>(v, field_def->offset(),
679 sizeof(uoffset_t)) ||
680 !v.VerifyString(flatbuffers::GetFieldS(*table, *field_def))) {
681 return false;
682 }
683 break;
684 case reflection::Vector:
685 if (!VerifyVector(v, schema, *table, *field_def)) return false;
686 break;
687 case reflection::Obj: {
688 auto child_obj = schema.objects()->Get(field_def->type()->index());
689 if (child_obj->is_struct()) {
690 if (!VerifyStruct(v, *table, field_def->offset(), *child_obj,
691 field_def->required())) {
692 return false;
693 }
694 } else {
695 if (!VerifyObject(v, schema, *child_obj,
696 flatbuffers::GetFieldT(*table, *field_def),
697 field_def->required())) {
698 return false;
699 }
700 }
701 break;
702 }
703 case reflection::Union: {
704 // get union type from the prev field
705 voffset_t utype_offset = field_def->offset() - sizeof(voffset_t);
706 auto utype = table->GetField<uint8_t>(utype_offset, 0);
707 auto uval = reinterpret_cast<const uint8_t *>(
708 flatbuffers::GetFieldT(*table, *field_def));
709 if (!VerifyUnion(v, schema, utype, uval, *field_def)) { return false; }
710 break;
711 }
712 default: FLATBUFFERS_ASSERT(false); break;
713 }
714 }
715
716 if (!v.EndTable()) return false;
717
718 return true;
719}
720
721bool Verify(const reflection::Schema &schema, const reflection::Object &root,
722 const uint8_t *buf, size_t length, uoffset_t max_depth /*= 64*/,
723 uoffset_t max_tables /*= 1000000*/) {
724 Verifier v(buf, length, max_depth, max_tables);
725 return VerifyObject(v, schema, root, flatbuffers::GetAnyRoot(buf), true);
726}
727
728} // namespace flatbuffers
729