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/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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
*
* https://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.
*/
#ifndef avro_Reader_hh__
#define avro_Reader_hh__
#include <array>
#include <boost/noncopyable.hpp>
#include <cstdint>
#include <vector>
#include "Config.hh"
#include "Types.hh"
#include "Validator.hh"
#include "Zigzag.hh"
#include "buffer/BufferReader.hh"
namespace avro {
///
/// Parses from an avro encoding to the requested type. Assumes the next item
/// in the avro binary data is the expected type.
///
template<class ValidatorType>
class ReaderImpl : private boost::noncopyable {
public:
explicit ReaderImpl(const InputBuffer &buffer) : reader_(buffer) {}
ReaderImpl(const ValidSchema &schema, const InputBuffer &buffer) : validator_(schema),
reader_(buffer) {}
void readValue(Null &) {
validator_.checkTypeExpected(AVRO_NULL);
}
void readValue(bool &val) {
validator_.checkTypeExpected(AVRO_BOOL);
uint8_t intVal = 0;
reader_.read(intVal);
val = (intVal != 0);
}
void readValue(int32_t &val) {
validator_.checkTypeExpected(AVRO_INT);
auto encoded = static_cast<uint32_t>(readVarInt());
val = decodeZigzag32(encoded);
}
void readValue(int64_t &val) {
validator_.checkTypeExpected(AVRO_LONG);
uint64_t encoded = readVarInt();
val = decodeZigzag64(encoded);
}
void readValue(float &val) {
validator_.checkTypeExpected(AVRO_FLOAT);
union {
float f;
uint32_t i;
} v;
reader_.read(v.i);
val = v.f;
}
void readValue(double &val) {
validator_.checkTypeExpected(AVRO_DOUBLE);
union {
double d;
uint64_t i;
} v = { 0 };
reader_.read(v.i);
val = v.d;
}
void readValue(std::string &val) {
validator_.checkTypeExpected(AVRO_STRING);
auto size = static_cast<size_t>(readSize());
reader_.read(val, size);
}
void readBytes(std::vector<uint8_t> &val) {
validator_.checkTypeExpected(AVRO_BYTES);
auto size = static_cast<size_t>(readSize());
val.resize(size);
reader_.read(reinterpret_cast<char *>(val.data()), size);
}
void readFixed(uint8_t *val, size_t size) {
validator_.checkFixedSizeExpected(size);
reader_.read(reinterpret_cast<char *>(val), size);
}
template<size_t N>
void readFixed(uint8_t (&val)[N]) {
this->readFixed(val, N);
}
template<size_t N>
void readFixed(std::array<uint8_t, N> &val) {
this->readFixed(val.data(), N);
}
void readRecord() {
validator_.checkTypeExpected(AVRO_RECORD);
validator_.checkTypeExpected(AVRO_LONG);
validator_.setCount(1);
}
void readRecordEnd() {
validator_.checkTypeExpected(AVRO_RECORD);
validator_.checkTypeExpected(AVRO_LONG);
validator_.setCount(0);
}
int64_t readArrayBlockSize() {
validator_.checkTypeExpected(AVRO_ARRAY);
return readCount();
}
int64_t readUnion() {
validator_.checkTypeExpected(AVRO_UNION);
return readCount();
}
int64_t readEnum() {
validator_.checkTypeExpected(AVRO_ENUM);
return readCount();
}
int64_t readMapBlockSize() {
validator_.checkTypeExpected(AVRO_MAP);
return readCount();
}
Type nextType() const {
return validator_.nextTypeExpected();
}
bool currentRecordName(std::string &name) const {
return validator_.getCurrentRecordName(name);
}
bool nextFieldName(std::string &name) const {
return validator_.getNextFieldName(name);
}
private:
uint64_t readVarInt() {
uint64_t encoded = 0;
uint8_t val = 0;
int shift = 0;
do {
reader_.read(val);
uint64_t newBits = static_cast<uint64_t>(val & 0x7f) << shift;
encoded |= newBits;
shift += 7;
} while (val & 0x80);
return encoded;
}
int64_t readSize() {
uint64_t encoded = readVarInt();
int64_t size = decodeZigzag64(encoded);
return size;
}
int64_t readCount() {
validator_.checkTypeExpected(AVRO_LONG);
int64_t count = readSize();
validator_.setCount(count);
return count;
}
ValidatorType validator_;
BufferReader reader_;
};
using Reader = ReaderImpl<NullValidator>;
using ValidatingReader = ReaderImpl<Validator>;
} // namespace avro
#endif
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