foundationdb/fdbclient/Atomic.h

282 lines
9.2 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 "CommitTransaction.h"
static 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);
}
static 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);
}
static ValueRef doAndV2(const Optional<ValueRef>& existingValueOptional, const ValueRef& otherOperand, Arena& ar) {
if (!existingValueOptional.present())
return otherOperand;
return doAnd(existingValueOptional, otherOperand, ar);
}
static 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);
}
static 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);
}
static 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);
}
static 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;
}
static 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;
}
static 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;
}
static ValueRef doMinV2(const Optional<ValueRef>& existingValueOptional, const ValueRef& otherOperand, Arena& ar) {
if (!existingValueOptional.present())
return otherOperand;
return doMin(existingValueOptional, otherOperand, ar);
}
static 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;
}
/*
* Returns the range corresponding to the specified versionstamp key.
*/
static KeyRangeRef getVersionstampKeyRange(Arena& arena, const KeyRef &key, const KeyRef &maxKey) {
KeyRef begin(arena, key);
KeyRef end(arena, key);
if (begin.size() < 2)
throw client_invalid_operation();
int16_t pos;
memcpy(&pos, begin.end() - sizeof(int16_t), sizeof(int16_t));
pos = littleEndian16(pos);
begin = begin.substr(0, begin.size() - 2);
end = end.substr(0, end.size() - 1);
mutateString(end)[end.size()-1] = 0;
if (pos < 0 || pos + 10 > begin.size())
throw client_invalid_operation();
memset(mutateString(begin) + pos, 0, 10);
memset(mutateString(end) + pos, '\xff', 10);
return KeyRangeRef(begin, std::min(end, maxKey));
}
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) );
}
static void transformSetVersionstampedKey( MutationRef& mutation, Version version, uint16_t transactionNumber ) {
// This transforms a SetVersionstampedKey mutation into a SetValue mutation.
// It is the responsibility of the caller to also add a write conflict range for the new mutation's key.
if (mutation.param1.size() >= 2) {
int16_t pos;
memcpy(&pos, mutation.param1.end() - sizeof(int16_t), sizeof(int16_t));
pos = littleEndian16(pos);
mutation.param1 = mutation.param1.substr(0, mutation.param1.size() - 2);
if (pos >= 0 && pos + 10 <= mutation.param1.size()) {
placeVersionstamp( mutateString(mutation.param1) + pos, version, transactionNumber );
}
}
mutation.type = MutationRef::SetValue;
}
static void transformSetVersionstampedValue( MutationRef& mutation, Version version, uint16_t transactionNumber ) {
if (mutation.param2.size() >= 10)
placeVersionstamp( mutateString(mutation.param2), version, transactionNumber );
mutation.type = MutationRef::SetValue;
}
#endif