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- #include "varint.h"
- #include "zigzag.h"
- #include <util/generic/yexception.h>
- namespace NYson {
- ////////////////////////////////////////////////////////////////////////////////
- int WriteVarUInt64(IOutputStream* output, ui64 value) {
- bool stop = false;
- int bytesWritten = 0;
- while (!stop) {
- ++bytesWritten;
- ui8 byte = static_cast<ui8>(value | 0x80);
- value >>= 7;
- if (value == 0) {
- stop = true;
- byte &= 0x7F;
- }
- output->Write(byte);
- }
- return bytesWritten;
- }
- int WriteVarInt32(IOutputStream* output, i32 value) {
- return WriteVarUInt64(output, static_cast<ui64>(ZigZagEncode32(value)));
- }
- int WriteVarInt64(IOutputStream* output, i64 value) {
- return WriteVarUInt64(output, static_cast<ui64>(ZigZagEncode64(value)));
- }
- int ReadVarUInt64(IInputStream* input, ui64* value) {
- size_t count = 0;
- ui64 result = 0;
- ui8 byte = 0;
- do {
- if (7 * count > 8 * sizeof(ui64)) {
- ythrow yexception() << "The data is too long to read ui64";
- }
- if (input->Read(&byte, 1) != 1) {
- ythrow yexception() << "The data is too short to read ui64";
- }
- result |= (static_cast<ui64>(byte & 0x7F)) << (7 * count);
- ++count;
- } while (byte & 0x80);
- *value = result;
- return count;
- }
- int ReadVarInt32(IInputStream* input, i32* value) {
- ui64 varInt;
- int bytesRead = ReadVarUInt64(input, &varInt);
- if (varInt > Max<ui32>()) {
- ythrow yexception() << "The data is too long to read i32";
- }
- *value = ZigZagDecode32(static_cast<ui32>(varInt));
- return bytesRead;
- }
- int ReadVarInt64(IInputStream* input, i64* value) {
- ui64 varInt;
- int bytesRead = ReadVarUInt64(input, &varInt);
- *value = ZigZagDecode64(varInt);
- return bytesRead;
- }
- } // namespace NYson
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