Select Git revision
op_cache.cpp
-
Adrien Béraud authoredAdrien Béraud authored
Code owners
Assign users and groups as approvers for specific file changes. Learn more.
op_cache.cpp 7.29 KiB
/*
* Copyright (C) 2019 Savoir-faire Linux Inc.
* Author(s) : Adrien Béraud <adrien.beraud@savoirfairelinux.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 3 of the License, or
* (at your option) any later version.
*
* 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
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <https://www.gnu.org/licenses/>.
*/
#include "op_cache.h"
namespace dht {
constexpr const std::chrono::seconds OpCache::EXPIRATION;
bool
OpValueCache::onValuesAdded(const std::vector<Sp<Value>>& vals) {
std::vector<Sp<Value>> newValues;
for (const auto& v : vals) {
auto viop = values.emplace(v->id, v);
if (viop.second) {
newValues.emplace_back(v);
} else {
viop.first->second.refCount++;
}
}
return newValues.empty() ? true : callback(newValues, false);
}
bool
OpValueCache::onValuesExpired(const std::vector<Sp<Value>>& vals) {
std::vector<Sp<Value>> expiredValues;
for (const auto& v : vals) {
auto vit = values.find(v->id);
if (vit != values.end()) {
vit->second.refCount--;
if (not vit->second.refCount) {
expiredValues.emplace_back(std::move(vit->second.data));
values.erase(vit);
}
}
}
return expiredValues.empty() ? true : callback(expiredValues, true);
}
bool
OpValueCache::onValuesExpired(const std::vector<Value::Id>& vids)
{
std::vector<Sp<Value>> expiredValues;
for (const auto& vid : vids) {
auto vit = values.find(vid);
if (vit != values.end()) {
vit->second.refCount--;
if (not vit->second.refCount) {
expiredValues.emplace_back(std::move(vit->second.data));
values.erase(vit);
}
}
}
return expiredValues.empty() ? true : callback(expiredValues, true);
}
std::vector<Sp<Value>>
OpValueCache::get(const Value::Filter& filter) const {
std::vector<Sp<Value>> ret;
if (not filter)
ret.reserve(values.size());
for (const auto& v : values)
if (not filter or filter(*v.second.data))
ret.emplace_back(v.second.data);
return ret;
}
Sp<Value>
OpValueCache::get(Value::Id id) const {
auto v = values.find(id);
if (v == values.end())
return {};
return v->second.data;
}
std::vector<Sp<Value>>
OpValueCache::getValues() const {
std::vector<Sp<Value>> ret;
ret.reserve(values.size());
for (const auto& v : values)
ret.emplace_back(v.second.data);
return ret;
}
void
OpCache::onValuesAdded(const std::vector<Sp<Value>>& vals) {
if (not listeners.empty()) {
std::vector<LocalListener> list;
list.reserve(listeners.size());
for (const auto& l : listeners)
list.emplace_back(l.second);
for (auto& l : list)
l.get_cb(l.filter.filter(vals), false);
}
}
void
OpCache::onValuesExpired(const std::vector<Sp<Value>>& vals) {
if (not listeners.empty()) {
std::vector<LocalListener> list;
list.reserve(listeners.size());
for (const auto& l : listeners)
list.emplace_back(l.second);
for (auto& l : list)
l.get_cb(l.filter.filter(vals), true);
}
}
time_point
OpCache::getExpiration() const {
if (not listeners.empty())
return time_point::max();
return lastRemoved + EXPIRATION;
}
SearchCache::OpMap::iterator
SearchCache::getOp(const Sp<Query>& q)
{
// find exact match
auto op = ops.find(q);
if (op != ops.end())
return op;
// find satisfying query
for (auto it = ops.begin(); it != ops.end(); it++) {
if (q->isSatisfiedBy(*it->first)) {
return it;
}
}
return ops.end();
}
SearchCache::OpMap::const_iterator
SearchCache::getOp(const Sp<Query>& q) const
{
// find exact match
auto op = ops.find(q);
if (op != ops.cend())
return op;
// find satisfying query
for (auto it = ops.begin(); it != ops.end(); it++) {
if (q->isSatisfiedBy(*it->first)) {
return it;
}
}
return ops.cend();
}
size_t
SearchCache::listen(const ValueCallback& get_cb, const Sp<Query>& q, const Value::Filter& filter, const OnListen& onListen)
{
// find exact match
auto op = getOp(q);
if (op == ops.end()) {
// New query
op = ops.emplace(q, std::unique_ptr<OpCache>(new OpCache)).first;
auto& cache = *op->second;
cache.searchToken = onListen(q, [&](const std::vector<Sp<Value>>& values, bool expired){
return cache.onValue(values, expired);
}, [&](ListenSyncStatus status) {
cache.onNodeChanged(status);
});
}
auto token = nextToken_++;
if (nextToken_ == 0)
nextToken_++;
return op->second->addListener(token, get_cb, q, filter) ? token : 0;
}
bool
SearchCache::cancelListen(size_t gtoken, const time_point& now) {
for (auto& op : ops) {
if (op.second->removeListener(gtoken, now)) {
nextExpiration_ = std::min(nextExpiration_, op.second->getExpiration());
return true;
}
}
return false;
}
void
SearchCache::cancelAll(const std::function<void(size_t)>& onCancel) {
for (auto& op : ops) {
auto cache = std::move(op.second);
cache->removeAll();
onCancel(cache->searchToken);
}
ops.clear();
}
time_point
SearchCache::expire(const time_point& now, const std::function<void(size_t)>& onCancel) {
nextExpiration_ = time_point::max();
auto ret = nextExpiration_;
for (auto it = ops.begin(); it != ops.end();) {
auto expiration = it->second->getExpiration();
if (expiration < now) {
auto cache = std::move(it->second);
it = ops.erase(it);
onCancel(cache->searchToken);
} else {
nextExpiration_ = std::min(nextExpiration_, expiration);
ret = nextExpiration_;
++it;
}
}
return ret;
}
bool
SearchCache::get(const Value::Filter& f, const Sp<Query>& q, const GetCallback& gcb, const DoneCallback& dcb) const
{
auto op = getOp(q);
if (op != ops.end()) {
auto vals = op->second->get(f);
if ((not vals.empty() and not gcb(vals)) or op->second->isSynced()) {
dcb(true, {});
return true;
}
}
return false;
}
std::vector<Sp<Value>>
SearchCache::get(const Value::Filter& filter) const {
if (ops.size() == 1)
return ops.begin()->second->get(filter);
std::map<Value::Id, Sp<Value>> c;
for (const auto& op : ops) {
for (const auto& v : op.second->get(filter))
c.emplace(v->id, v);
}
std::vector<Sp<Value>> ret;
ret.reserve(c.size());
for (auto& v : c)
ret.emplace_back(std::move(v.second));
return ret;
}
Sp<Value>
SearchCache::get(Value::Id id) const {
for (const auto& op : ops)
if (auto v = op.second->get(id))
return v;
return {};
}
}