+++ /dev/null
-// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
-/*
- * This file is open source software, licensed to you under the terms
- * of the Apache License, Version 2.0 (the "License"). See the NOTICE file
- * distributed with this work for additional information regarding copyright
- * ownership. 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.
- */
-/*
- * Copyright (C) 2014 Cloudius Systems, Ltd.
- */
-/*
- * Ceph - scalable distributed file system
- *
- * Copyright (C) 2015 XSky <haomai@xsky.com>
- *
- * Author: Haomai Wang <haomaiwang@gmail.com>
- *
- * This is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License version 2.1, as published by the Free Software
- * Foundation. See file COPYING.
- *
- */
-
-#ifndef CEPH_MSG_PACKET_UTIL_H_
-#define CEPH_MSG_PACKET_UTIL_H_
-
-#include <map>
-#include <iostream>
-
-#include "Packet.h"
-
-template <typename Offset, typename Tag>
-class packet_merger {
- private:
- static uint64_t& linearizations_ref() {
- static thread_local uint64_t linearization_count;
- return linearization_count;
- }
- public:
- std::map<Offset, Packet> map;
-
- static uint64_t linearizations() {
- return linearizations_ref();
- }
-
- void merge(Offset offset, Packet p) {
- bool insert = true;
- auto beg = offset;
- auto end = beg + p.len();
- // Fisrt, try to merge the packet with existing segment
- for (auto it = map.begin(); it != map.end();) {
- auto& seg_pkt = it->second;
- auto seg_beg = it->first;
- auto seg_end = seg_beg + seg_pkt.len();
- // There are 6 cases:
- if (seg_beg <= beg && end <= seg_end) {
- // 1) seg_beg beg end seg_end
- // We already have data in this packet
- return;
- } else if (beg <= seg_beg && seg_end <= end) {
- // 2) beg seg_beg seg_end end
- // The new segment contains more data than this old segment
- // Delete the old one, insert the new one
- it = map.erase(it);
- insert = true;
- break;
- } else if (beg < seg_beg && seg_beg <= end && end <= seg_end) {
- // 3) beg seg_beg end seg_end
- // Merge two segments, trim front of old segment
- auto trim = end - seg_beg;
- seg_pkt.trim_front(trim);
- p.append(std::move(seg_pkt));
- // Delete the old one, insert the new one
- it = map.erase(it);
- insert = true;
- break;
- } else if (seg_beg <= beg && beg <= seg_end && seg_end < end) {
- // 4) seg_beg beg seg_end end
- // Merge two segments, trim front of new segment
- auto trim = seg_end - beg;
- p.trim_front(trim);
- // Append new data to the old segment, keep the old segment
- seg_pkt.append(std::move(p));
- seg_pkt.linearize();
- ++linearizations_ref();
- insert = false;
- break;
- } else {
- // 5) beg end < seg_beg seg_end
- // or
- // 6) seg_beg seg_end < beg end
- // Can not merge with this segment, keep looking
- it++;
- insert = true;
- }
- }
-
- if (insert) {
- p.linearize();
- ++linearizations_ref();
- map.emplace(beg, std::move(p));
- }
-
- // Second, merge adjacent segments after this packet has been merged,
- // becasue this packet might fill a "whole" and make two adjacent
- // segments mergable
- for (auto it = map.begin(); it != map.end();) {
- // The first segment
- auto& seg_pkt = it->second;
- auto seg_beg = it->first;
- auto seg_end = seg_beg + seg_pkt.len();
-
- // The second segment
- auto it_next = it;
- it_next++;
- if (it_next == map.end()) {
- break;
- }
- auto& p = it_next->second;
- auto beg = it_next->first;
- auto end = beg + p.len();
-
- // Merge the the second segment into first segment if possible
- if (seg_beg <= beg && beg <= seg_end && seg_end < end) {
- // Merge two segments, trim front of second segment
- auto trim = seg_end - beg;
- p.trim_front(trim);
- // Append new data to the first segment, keep the first segment
- seg_pkt.append(std::move(p));
-
- // Delete the second segment
- map.erase(it_next);
-
- // Keep merging this first segment with its new next packet
- // So we do not update the iterator: it
- continue;
- } else if (end <= seg_end) {
- // The first segment has all the data in the second segment
- // Delete the second segment
- map.erase(it_next);
- continue;
- } else if (seg_end < beg) {
- // Can not merge first segment with second segment
- it = it_next;
- continue;
- } else {
- // If we reach here, we have a bug with merge.
- std::cout << "packet_merger: merge error\n";
- abort();
- break;
- }
- }
- }
-};
-
-#endif
Code Review / stor4nfv.git / blobdiff