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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. 
 */ 
 
 
#include "Zigzag.hh" 
 
namespace avro { 
 
uint64_t 
encodeZigzag64(int64_t input) 
{ 
    // cppcheck-suppress shiftTooManyBitsSigned 
    return ((input << 1) ^ (input >> 63)); 
} 
 
int64_t 
decodeZigzag64(uint64_t input) 
{ 
    return static_cast<int64_t>(((input >> 1) ^ -(static_cast<int64_t>(input) & 1))); 
} 
 
uint32_t 
encodeZigzag32(int32_t input) 
{ 
    // cppcheck-suppress shiftTooManyBitsSigned 
    return ((input << 1) ^ (input >> 31)); 
} 
 
int32_t 
decodeZigzag32(uint32_t input) 
{ 
    return static_cast<int32_t>(((input >> 1) ^ -(static_cast<int64_t>(input) & 1))); 
} 
 
size_t 
encodeInt64(int64_t input, std::array<uint8_t, 10> &output) 
{ 
    // get the zigzag encoding 
    uint64_t val = encodeZigzag64(input); 
 
    // put values in an array of bytes with variable length encoding 
    const int mask  = 0x7F; 
    output[0] = val & mask; 
    size_t bytesOut = 1; 
    while( val >>=7 ) { 
        output[bytesOut-1] |= 0x80; 
        output[bytesOut++] = (val & mask); 
    } 
 
    return bytesOut; 
} 
 
size_t 
encodeInt32(int32_t input, std::array<uint8_t, 5> &output) 
{ 
    // get the zigzag encoding 
    uint32_t val = encodeZigzag32(input); 
 
    // put values in an array of bytes with variable length encoding 
    const int mask  = 0x7F; 
    output[0] = val & mask; 
    size_t bytesOut = 1; 
    while( val >>=7 ) { 
        output[bytesOut-1] |= 0x80; 
        output[bytesOut++] = (val & mask); 
    } 
 
    return bytesOut; 
} 
 
} // namespace avro