• Main Page
  • Related Pages
  • Namespaces
  • Data Structures
  • Files
  • File List
  • Globals

HttpConnectionCount.h

Go to the documentation of this file.
00001 /** @file
00002 
00003   A brief file description
00004 
00005   @section license License
00006 
00007   Licensed to the Apache Software Foundation (ASF) under one
00008   or more contributor license agreements.  See the NOTICE file
00009   distributed with this work for additional information
00010   regarding copyright ownership.  The ASF licenses this file
00011   to you under the Apache License, Version 2.0 (the
00012   "License"); you may not use this file except in compliance
00013   with the License.  You may obtain a copy of the License at
00014 
00015       http://www.apache.org/licenses/LICENSE-2.0
00016 
00017   Unless required by applicable law or agreed to in writing, software
00018   distributed under the License is distributed on an "AS IS" BASIS,
00019   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
00020   See the License for the specific language governing permissions and
00021   limitations under the License.
00022  */
00023 
00024 //
00025 #include "libts.h"
00026 #include "Map.h"
00027 
00028 #ifndef _HTTP_CONNECTION_COUNT_H_
00029 
00030 /**
00031  * Singleton class to keep track of the number of connections per host
00032  */
00033 class ConnectionCount
00034 {
00035 public:
00036   /**
00037    * Static method to get the instance of the class
00038    * @return Returns a pointer to the instance of the class
00039    */
00040   static ConnectionCount *getInstance() {
00041     return &_connectionCount;
00042   }
00043 
00044   /**
00045    * Gets the number of connections for the host
00046    * @param ip IP address of the host
00047    * @return Number of connections
00048    */
00049   int getCount(const IpEndpoint& addr) {
00050     ink_mutex_acquire(&_mutex);
00051     int count = _hostCount.get(ConnAddr(addr));
00052     ink_mutex_release(&_mutex);
00053     return count;
00054   }
00055 
00056   /**
00057    * Change (increment/decrement) the connection count
00058    * @param ip IP address of the host
00059    * @param delta Default is +1, can be set to negative to decrement
00060    */
00061   void incrementCount(const IpEndpoint& addr, const int delta = 1) {
00062     ConnAddr caddr(addr);
00063     ink_mutex_acquire(&_mutex);
00064     int count = _hostCount.get(caddr);
00065     _hostCount.put(caddr, count + delta);
00066     ink_mutex_release(&_mutex);
00067   }
00068 
00069   struct ConnAddr {
00070     IpEndpoint _addr;
00071 
00072     ConnAddr() { ink_zero(_addr); }
00073     ConnAddr(int x) { ink_release_assert(x == 0); ink_zero(_addr); }
00074     ConnAddr(const IpEndpoint& addr) : _addr(addr) { }
00075     operator bool() { return ats_is_ip(&_addr); }
00076   };
00077   
00078   class ConnAddrHashFns {
00079   public:
00080       static uintptr_t hash(ConnAddr& addr) { return (uintptr_t) ats_ip_hash(&addr._addr.sa); }
00081       static int equal(ConnAddr& a, ConnAddr& b) { return ats_ip_addr_eq(&a._addr, &b._addr); }
00082   };
00083 
00084 private:
00085   // Hide the constructor and copy constructor
00086   ConnectionCount() {
00087     ink_mutex_init(&_mutex, "ConnectionCountMutex");
00088   }
00089   ConnectionCount(const ConnectionCount & /* x ATS_UNUSED */) { }
00090 
00091   static ConnectionCount _connectionCount;
00092   HashMap<ConnAddr, ConnAddrHashFns, int> _hostCount;
00093   ink_mutex _mutex;
00094 };
00095 
00096 #endif

Generated by  doxygen 1.7.1