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