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/*
* Copyright (c) 2019, The Android Open Source Project
*
* 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.
*/
#include "cppbor.h"
#include "cppbor_parse.h"
#define LOG_TAG "CppBor"
#include <android-base/logging.h>
namespace cppbor {
namespace {
template <typename T, typename Iterator, typename = std::enable_if<std::is_unsigned<T>::value>>
Iterator writeBigEndian(T value, Iterator pos) {
for (unsigned i = 0; i < sizeof(value); ++i) {
*pos++ = static_cast<uint8_t>(value >> (8 * (sizeof(value) - 1)));
value = static_cast<T>(value << 8);
}
return pos;
}
template <typename T, typename = std::enable_if<std::is_unsigned<T>::value>>
void writeBigEndian(T value, std::function<void(uint8_t)>& cb) {
for (unsigned i = 0; i < sizeof(value); ++i) {
cb(static_cast<uint8_t>(value >> (8 * (sizeof(value) - 1))));
value = static_cast<T>(value << 8);
}
}
} // namespace
size_t headerSize(uint64_t addlInfo) {
if (addlInfo < ONE_BYTE_LENGTH) return 1;
if (addlInfo <= std::numeric_limits<uint8_t>::max()) return 2;
if (addlInfo <= std::numeric_limits<uint16_t>::max()) return 3;
if (addlInfo <= std::numeric_limits<uint32_t>::max()) return 5;
return 9;
}
uint8_t* encodeHeader(MajorType type, uint64_t addlInfo, uint8_t* pos, const uint8_t* end) {
size_t sz = headerSize(addlInfo);
if (end - pos < static_cast<ssize_t>(sz)) return nullptr;
switch (sz) {
case 1:
*pos++ = type | static_cast<uint8_t>(addlInfo);
return pos;
case 2:
*pos++ = type | ONE_BYTE_LENGTH;
*pos++ = static_cast<uint8_t>(addlInfo);
return pos;
case 3:
*pos++ = type | TWO_BYTE_LENGTH;
return writeBigEndian(static_cast<uint16_t>(addlInfo), pos);
case 5:
*pos++ = type | FOUR_BYTE_LENGTH;
return writeBigEndian(static_cast<uint32_t>(addlInfo), pos);
case 9:
*pos++ = type | EIGHT_BYTE_LENGTH;
return writeBigEndian(addlInfo, pos);
default:
CHECK(false); // Impossible to get here.
return nullptr;
}
}
void encodeHeader(MajorType type, uint64_t addlInfo, EncodeCallback encodeCallback) {
size_t sz = headerSize(addlInfo);
switch (sz) {
case 1:
encodeCallback(type | static_cast<uint8_t>(addlInfo));
break;
case 2:
encodeCallback(type | ONE_BYTE_LENGTH);
encodeCallback(static_cast<uint8_t>(addlInfo));
break;
case 3:
encodeCallback(type | TWO_BYTE_LENGTH);
writeBigEndian(static_cast<uint16_t>(addlInfo), encodeCallback);
break;
case 5:
encodeCallback(type | FOUR_BYTE_LENGTH);
writeBigEndian(static_cast<uint32_t>(addlInfo), encodeCallback);
break;
case 9:
encodeCallback(type | EIGHT_BYTE_LENGTH);
writeBigEndian(addlInfo, encodeCallback);
break;
default:
CHECK(false); // Impossible to get here.
}
}
bool Item::operator==(const Item& other) const& {
if (type() != other.type()) return false;
switch (type()) {
case UINT:
return *asUint() == *(other.asUint());
case NINT:
return *asNint() == *(other.asNint());
case BSTR:
return *asBstr() == *(other.asBstr());
case TSTR:
return *asTstr() == *(other.asTstr());
case ARRAY:
return *asArray() == *(other.asArray());
case MAP:
return *asMap() == *(other.asMap());
case SIMPLE:
return *asSimple() == *(other.asSimple());
case SEMANTIC:
return *asSemantic() == *(other.asSemantic());
default:
CHECK(false); // Impossible to get here.
return false;
}
}
Nint::Nint(int64_t v) : mValue(v) {
CHECK(v < 0) << "Only negative values allowed";
}
bool Simple::operator==(const Simple& other) const& {
if (simpleType() != other.simpleType()) return false;
switch (simpleType()) {
case BOOLEAN:
return *asBool() == *(other.asBool());
case NULL_T:
return true;
default:
CHECK(false); // Impossible to get here.
return false;
}
}
uint8_t* Bstr::encode(uint8_t* pos, const uint8_t* end) const {
pos = encodeHeader(mValue.size(), pos, end);
if (!pos || end - pos < static_cast<ptrdiff_t>(mValue.size())) return nullptr;
return std::copy(mValue.begin(), mValue.end(), pos);
}
void Bstr::encodeValue(EncodeCallback encodeCallback) const {
for (auto c : mValue) {
encodeCallback(c);
}
}
uint8_t* Tstr::encode(uint8_t* pos, const uint8_t* end) const {
pos = encodeHeader(mValue.size(), pos, end);
if (!pos || end - pos < static_cast<ptrdiff_t>(mValue.size())) return nullptr;
return std::copy(mValue.begin(), mValue.end(), pos);
}
void Tstr::encodeValue(EncodeCallback encodeCallback) const {
for (auto c : mValue) {
encodeCallback(static_cast<uint8_t>(c));
}
}
bool CompoundItem::operator==(const CompoundItem& other) const& {
return type() == other.type() //
&& addlInfo() == other.addlInfo() //
// Can't use vector::operator== because the contents are pointers. std::equal lets us
// provide a predicate that does the dereferencing.
&& std::equal(mEntries.begin(), mEntries.end(), other.mEntries.begin(),
[](auto& a, auto& b) -> bool { return *a == *b; });
}
uint8_t* CompoundItem::encode(uint8_t* pos, const uint8_t* end) const {
pos = encodeHeader(addlInfo(), pos, end);
if (!pos) return nullptr;
for (auto& entry : mEntries) {
pos = entry->encode(pos, end);
if (!pos) return nullptr;
}
return pos;
}
void CompoundItem::encode(EncodeCallback encodeCallback) const {
encodeHeader(addlInfo(), encodeCallback);
for (auto& entry : mEntries) {
entry->encode(encodeCallback);
}
}
void Map::assertInvariant() const {
CHECK(mEntries.size() % 2 == 0);
}
std::unique_ptr<Item> Map::clone() const {
assertInvariant();
auto res = std::make_unique<Map>();
for (size_t i = 0; i < mEntries.size(); i += 2) {
res->add(mEntries[i]->clone(), mEntries[i + 1]->clone());
}
return res;
}
std::unique_ptr<Item> Array::clone() const {
auto res = std::make_unique<Array>();
for (size_t i = 0; i < mEntries.size(); i++) {
res->add(mEntries[i]->clone());
}
return res;
}
void Semantic::assertInvariant() const {
CHECK(mEntries.size() == 1);
}
} // namespace cppbor