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/**
* Copyright (C) 2018-present MongoDB, Inc.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the Server Side Public License, version 1,
* as published by MongoDB, Inc.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* Server Side Public License for more details.
*
* You should have received a copy of the Server Side Public License
* along with this program. If not, see
* <http://www.mongodb.com/licensing/server-side-public-license>.
*
* As a special exception, the copyright holders give permission to link the
* code of portions of this program with the OpenSSL library under certain
* conditions as described in each individual source file and distribute
* linked combinations including the program with the OpenSSL library. You
* must comply with the Server Side Public License in all respects for
* all of the code used other than as permitted herein. If you modify file(s)
* with this exception, you may extend this exception to your version of the
* file(s), but you are not obligated to do so. If you do not wish to do so,
* delete this exception statement from your version. If you delete this
* exception statement from all source files in the program, then also delete
* it in the license file.
*/
#pragma once
#include <cstring>
#include "mongo/base/data_type.h"
namespace mongo {
template <char C, typename T>
struct Terminated {
Terminated() : value(DataType::defaultConstruct<T>()) {}
Terminated(T value) : value(std::move(value)) {}
T value;
operator T() const {
return value;
}
};
struct TerminatedHelper {
static Status makeLoadNoTerminalStatus(char c, size_t length, std::ptrdiff_t debug_offset);
static Status makeLoadShortReadStatus(char c,
size_t read,
size_t length,
std::ptrdiff_t debug_offset);
static Status makeStoreStatus(char c, size_t length, std::ptrdiff_t debug_offset);
};
template <char C, typename T>
struct DataType::Handler<Terminated<C, T>> {
using TerminatedType = Terminated<C, T>;
static Status load(TerminatedType* tt,
const char* ptr,
size_t length,
size_t* advanced,
std::ptrdiff_t debug_offset) {
size_t local_advanced = 0;
const char* end = static_cast<const char*>(std::memchr(ptr, C, length));
if (!end) {
return TerminatedHelper::makeLoadNoTerminalStatus(C, length, debug_offset);
}
auto status = DataType::load(
tt ? &tt->value : nullptr, ptr, end - ptr, &local_advanced, debug_offset);
if (!status.isOK()) {
return status;
}
if (local_advanced != static_cast<size_t>(end - ptr)) {
return TerminatedHelper::makeLoadShortReadStatus(
C, local_advanced, end - ptr, debug_offset);
}
if (advanced) {
*advanced = local_advanced + 1;
}
return Status::OK();
}
static Status store(const TerminatedType& tt,
char* ptr,
size_t length,
size_t* advanced,
std::ptrdiff_t debug_offset) {
size_t local_advanced = 0;
auto status = DataType::store(tt.value, ptr, length, &local_advanced, debug_offset);
if (!status.isOK()) {
return status;
}
if (length - local_advanced < 1) {
return TerminatedHelper::makeStoreStatus(C, length, debug_offset + local_advanced);
}
ptr[local_advanced] = C;
if (advanced) {
*advanced = local_advanced + 1;
}
return Status::OK();
}
static TerminatedType defaultConstruct() {
return TerminatedType();
}
};
} // namespace mongo
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