foundationdb/fdbclient/Atomic.h

316 lines
10 KiB
C++

/*
* Atomic.h
*
* This source file is part of the FoundationDB open source project
*
* Copyright 2013-2018 Apple Inc. and the FoundationDB project authors
*
* 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.
*/
#ifndef FLOW_FDBCLIENT_ATOMIC_H
#define FLOW_FDBCLIENT_ATOMIC_H
#pragma once
#include "fdbclient/CommitTransaction.h"
inline ValueRef doLittleEndianAdd(const Optional<ValueRef>& existingValueOptional,
const ValueRef& otherOperand,
Arena& ar) {
const ValueRef& existingValue = existingValueOptional.present() ? existingValueOptional.get() : StringRef();
if (!existingValue.size())
return otherOperand;
if (!otherOperand.size())
return otherOperand;
uint8_t* buf = new (ar) uint8_t[otherOperand.size()];
int i = 0;
int carry = 0;
for (i = 0; i < std::min(existingValue.size(), otherOperand.size()); i++) {
int sum = existingValue[i] + otherOperand[i] + carry;
buf[i] = sum;
carry = sum >> 8;
}
for (; i < otherOperand.size(); i++) {
int sum = otherOperand[i] + carry;
buf[i] = sum;
carry = sum >> 8;
}
return StringRef(buf, i);
}
inline ValueRef doAnd(const Optional<ValueRef>& existingValueOptional, const ValueRef& otherOperand, Arena& ar) {
const ValueRef& existingValue = existingValueOptional.present() ? existingValueOptional.get() : StringRef();
if (!otherOperand.size())
return otherOperand;
uint8_t* buf = new (ar) uint8_t[otherOperand.size()];
int i = 0;
for (i = 0; i < std::min(existingValue.size(), otherOperand.size()); i++)
buf[i] = existingValue[i] & otherOperand[i];
for (; i < otherOperand.size(); i++)
buf[i] = 0x0;
return StringRef(buf, i);
}
inline ValueRef doAndV2(const Optional<ValueRef>& existingValueOptional, const ValueRef& otherOperand, Arena& ar) {
if (!existingValueOptional.present())
return otherOperand;
return doAnd(existingValueOptional, otherOperand, ar);
}
inline ValueRef doOr(const Optional<ValueRef>& existingValueOptional, const ValueRef& otherOperand, Arena& ar) {
const ValueRef& existingValue = existingValueOptional.present() ? existingValueOptional.get() : StringRef();
if (!existingValue.size())
return otherOperand;
if (!otherOperand.size())
return otherOperand;
uint8_t* buf = new (ar) uint8_t[otherOperand.size()];
int i = 0;
for (i = 0; i < std::min(existingValue.size(), otherOperand.size()); i++)
buf[i] = existingValue[i] | otherOperand[i];
for (; i < otherOperand.size(); i++)
buf[i] = otherOperand[i];
return StringRef(buf, i);
}
inline ValueRef doXor(const Optional<ValueRef>& existingValueOptional, const ValueRef& otherOperand, Arena& ar) {
const ValueRef& existingValue = existingValueOptional.present() ? existingValueOptional.get() : StringRef();
if (!existingValue.size())
return otherOperand;
if (!otherOperand.size())
return otherOperand;
uint8_t* buf = new (ar) uint8_t[otherOperand.size()];
int i = 0;
for (i = 0; i < std::min(existingValue.size(), otherOperand.size()); i++)
buf[i] = existingValue[i] ^ otherOperand[i];
for (; i < otherOperand.size(); i++)
buf[i] = otherOperand[i];
return StringRef(buf, i);
}
inline ValueRef doAppendIfFits(const Optional<ValueRef>& existingValueOptional,
const ValueRef& otherOperand,
Arena& ar) {
const ValueRef& existingValue = existingValueOptional.present() ? existingValueOptional.get() : StringRef();
if (!existingValue.size())
return otherOperand;
if (!otherOperand.size())
return existingValue;
if (existingValue.size() + otherOperand.size() > CLIENT_KNOBS->VALUE_SIZE_LIMIT) {
TEST(true) // AppendIfFIts resulted in truncation
return existingValue;
}
uint8_t* buf = new (ar) uint8_t[existingValue.size() + otherOperand.size()];
int i, j;
for (i = 0; i < existingValue.size(); i++)
buf[i] = existingValue[i];
for (j = 0; j < otherOperand.size(); j++)
buf[i + j] = otherOperand[j];
return StringRef(buf, i + j);
}
inline ValueRef doMax(const Optional<ValueRef>& existingValueOptional, const ValueRef& otherOperand, Arena& ar) {
const ValueRef& existingValue = existingValueOptional.present() ? existingValueOptional.get() : StringRef();
if (!existingValue.size())
return otherOperand;
if (!otherOperand.size())
return otherOperand;
int i, j;
for (i = otherOperand.size() - 1; i >= existingValue.size(); i--) {
if (otherOperand[i] != 0) {
return otherOperand;
}
}
for (; i >= 0; i--) {
if (otherOperand[i] > existingValue[i]) {
return otherOperand;
} else if (otherOperand[i] < existingValue[i]) {
uint8_t* buf = new (ar) uint8_t[otherOperand.size()];
for (j = 0; j < std::min(existingValue.size(), otherOperand.size()); j++) {
buf[j] = existingValue[j];
}
for (; j < otherOperand.size(); j++) {
buf[j] = 0x0;
}
return StringRef(buf, j);
}
}
return otherOperand;
}
inline ValueRef doByteMax(const Optional<ValueRef>& existingValueOptional, const ValueRef& otherOperand, Arena& ar) {
if (!existingValueOptional.present())
return otherOperand;
const ValueRef& existingValue = existingValueOptional.get();
if (existingValue > otherOperand)
return existingValue;
return otherOperand;
}
inline ValueRef doMin(const Optional<ValueRef>& existingValueOptional, const ValueRef& otherOperand, Arena& ar) {
if (!otherOperand.size())
return otherOperand;
const ValueRef& existingValue = existingValueOptional.present() ? existingValueOptional.get() : StringRef();
int i, j;
for (i = otherOperand.size() - 1; i >= existingValue.size(); i--) {
if (otherOperand[i] != 0) {
uint8_t* buf = new (ar) uint8_t[otherOperand.size()];
for (j = 0; j < std::min(existingValue.size(), otherOperand.size()); j++) {
buf[j] = existingValue[j];
}
for (; j < otherOperand.size(); j++) {
buf[j] = 0x0;
}
return StringRef(buf, j);
}
}
for (; i >= 0; i--) {
if (otherOperand[i] > existingValue[i]) {
uint8_t* buf = new (ar) uint8_t[otherOperand.size()];
for (j = 0; j < std::min(existingValue.size(), otherOperand.size()); j++) {
buf[j] = existingValue[j];
}
for (; j < otherOperand.size(); j++) {
buf[j] = 0x0;
}
return StringRef(buf, j);
} else if (otherOperand[i] < existingValue[i]) {
return otherOperand;
}
}
return otherOperand;
}
inline ValueRef doMinV2(const Optional<ValueRef>& existingValueOptional, const ValueRef& otherOperand, Arena& ar) {
if (!existingValueOptional.present())
return otherOperand;
return doMin(existingValueOptional, otherOperand, ar);
}
inline ValueRef doByteMin(const Optional<ValueRef>& existingValueOptional, const ValueRef& otherOperand, Arena& ar) {
if (!existingValueOptional.present())
return otherOperand;
const ValueRef& existingValue = existingValueOptional.get();
if (existingValue < otherOperand)
return existingValue;
return otherOperand;
}
inline Optional<ValueRef> doCompareAndClear(const Optional<ValueRef>& existingValueOptional,
const ValueRef& otherOperand,
Arena& ar) {
if (!existingValueOptional.present() || existingValueOptional.get() == otherOperand) {
// Clear the value.
return Optional<ValueRef>();
}
return existingValueOptional; // No change required.
}
static void placeVersionstamp(uint8_t* destination, Version version, uint16_t transactionNumber) {
version = bigEndian64(version);
transactionNumber = bigEndian16(transactionNumber);
static_assert(sizeof(version) == 8, "version size mismatch");
memcpy(destination, &version, sizeof(version));
static_assert(sizeof(transactionNumber) == 2, "txn num size mismatch");
memcpy(destination + sizeof(version), &transactionNumber, sizeof(transactionNumber));
}
/*
* Returns the range corresponding to the specified versionstamp key.
*/
inline KeyRangeRef getVersionstampKeyRange(Arena& arena, const KeyRef& key, Version minVersion, const KeyRef& maxKey) {
KeyRef begin(arena, key);
KeyRef end(arena, key);
if (begin.size() < 4)
throw client_invalid_operation();
int32_t pos;
memcpy(&pos, begin.end() - sizeof(int32_t), sizeof(int32_t));
pos = littleEndian32(pos);
begin = begin.substr(0, begin.size() - 4);
end = end.substr(0, end.size() - 3);
mutateString(end)[end.size() - 1] = 0;
if (pos < 0 || pos + 10 > begin.size())
throw client_invalid_operation();
placeVersionstamp(mutateString(begin) + pos, minVersion, 0);
memset(mutateString(end) + pos, '\xff', 10);
return KeyRangeRef(begin, std::min(end, maxKey));
}
inline void transformVersionstampKey(StringRef& key, Version version, uint16_t transactionNumber) {
if (key.size() < 4)
throw client_invalid_operation();
int32_t pos;
memcpy(&pos, key.end() - sizeof(int32_t), sizeof(int32_t));
pos = littleEndian32(pos);
if (pos < 0 || pos + 10 > key.size())
throw client_invalid_operation();
placeVersionstamp(mutateString(key) + pos, version, transactionNumber);
}
inline void transformVersionstampMutation(MutationRef& mutation,
StringRef MutationRef::*param,
Version version,
uint16_t transactionNumber) {
if ((mutation.*param).size() >= 4) {
int32_t pos;
memcpy(&pos, (mutation.*param).end() - sizeof(int32_t), sizeof(int32_t));
pos = littleEndian32(pos);
mutation.*param = (mutation.*param).substr(0, (mutation.*param).size() - 4);
if (pos >= 0 && pos + 10 <= (mutation.*param).size()) {
placeVersionstamp(mutateString(mutation.*param) + pos, version, transactionNumber);
}
}
mutation.type = MutationRef::SetValue;
}
#endif