Alexandre Lision | 7fd5d3d | 2013-12-04 13:06:40 -0500 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2006, 2005, 2004 Erik Eliasson, Johan Bilien, Werner Dittmann |
| 3 | * |
| 4 | * This library is free software; you can redistribute it and/or |
| 5 | * modify it under the terms of the GNU Lesser General Public |
| 6 | * License as published by the Free Software Foundation; either |
| 7 | * version 2.1 of the License, or (at your option) any later version. |
| 8 | * |
| 9 | * This library is distributed in the hope that it will be useful, |
| 10 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 12 | * Lesser General Public License for more details. |
| 13 | * |
| 14 | * You should have received a copy of the GNU Lesser General Public |
| 15 | * License along with this library; if not, write to the Free Software |
| 16 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| 17 | */ |
| 18 | |
| 19 | |
| 20 | #ifndef _TIMEOUTPROVIDER_H_ |
| 21 | #define _TIMEOUTPROVIDER_H_ |
| 22 | |
| 23 | /** |
| 24 | * Provides a way to request timeouts after a number of milli seconds. |
| 25 | * |
| 26 | * A command is associated to each timeout. |
| 27 | * |
| 28 | * Modified to use the common c++ library functions and the STL |
| 29 | * list by Werner Dittmann. |
| 30 | * |
| 31 | * @author Erik Eliasson, eliasson@it.kth.se, 2003 |
| 32 | * @author Werner Dittmann <Werner.Dittmann@t-online.de> |
| 33 | */ |
| 34 | |
| 35 | #include <list> |
| 36 | #include <stdint.h> |
| 37 | |
| 38 | #include <common/Thread.h> |
| 39 | #include <common/osSpecifics.h> |
| 40 | |
| 41 | /** |
| 42 | * Represents a request of a "timeout" (delivery of a command to a |
| 43 | * "timeout receiver" after at least a specified time period). |
| 44 | * |
| 45 | * Slightly modified to use gettimeofday directly. |
| 46 | * |
| 47 | * @author Werner Dittmann |
| 48 | */ |
| 49 | template <class TOCommand, class TOSubscriber> |
| 50 | class TPRequest |
| 51 | { |
| 52 | |
| 53 | public: |
| 54 | |
| 55 | TPRequest( TOSubscriber tsi, int timeoutMs, const TOCommand &command): |
| 56 | subscriber(tsi) |
| 57 | { |
| 58 | when_ms = zrtpGetTickCount(); |
| 59 | |
| 60 | when_ms += timeoutMs; |
| 61 | this->command = command; |
| 62 | } |
| 63 | |
| 64 | /** |
| 65 | * @param t ms since Epoch |
| 66 | */ |
| 67 | bool happensBefore(uint64_t t) |
| 68 | { |
| 69 | if (when_ms < t) { |
| 70 | return true; |
| 71 | } |
| 72 | if (when_ms > t) { |
| 73 | return false; |
| 74 | } |
| 75 | return false; // if equal it does not "happens_before" |
| 76 | |
| 77 | } |
| 78 | |
| 79 | bool happensBefore(const TPRequest *req){ |
| 80 | return happensBefore(req->when_ms); |
| 81 | } |
| 82 | |
| 83 | /** |
| 84 | * Number of milli seconds until timeout from when this method is |
| 85 | * called |
| 86 | */ |
| 87 | int getMsToTimeout () |
| 88 | { |
| 89 | uint64_t now = zrtpGetTickCount(); |
| 90 | |
| 91 | if (happensBefore(now)) { |
| 92 | return 0; |
| 93 | } |
| 94 | else { |
| 95 | return (int)(when_ms - now); |
| 96 | } |
| 97 | } |
| 98 | |
| 99 | TOCommand getCommand() |
| 100 | { |
| 101 | return command; |
| 102 | } |
| 103 | |
| 104 | TOSubscriber getSubscriber() |
| 105 | { |
| 106 | return subscriber; |
| 107 | } |
| 108 | |
| 109 | /** |
| 110 | * Two timeout requests are considered equeal if they have |
| 111 | * the same subscriber AND command AND time when they |
| 112 | * occur. If one of the time is zero then this is a |
| 113 | * wildcard and matches always. |
| 114 | */ |
| 115 | bool operator==(const TPRequest<TOCommand, TOSubscriber> &req) |
| 116 | { |
| 117 | if (req.subscriber == subscriber && |
| 118 | req.command == command && |
| 119 | req.when_ms == when_ms) { |
| 120 | return true; |
| 121 | } |
| 122 | return false; |
| 123 | } |
| 124 | |
| 125 | private: |
| 126 | TOSubscriber subscriber; |
| 127 | uint64_t when_ms; // Time since Epoch in ms when the timeout |
| 128 | // will happen |
| 129 | |
| 130 | TOCommand command; // Command that will be delivered to the |
| 131 | // receiver (subscriber) of the timeout. |
| 132 | }; |
| 133 | |
| 134 | /** |
| 135 | * Class to generate objects giving timeout functionality. |
| 136 | * |
| 137 | * @author Erik Eliasson |
| 138 | * @author Werner Dittmann |
| 139 | */ |
| 140 | template<class TOCommand, class TOSubscriber> |
| 141 | class TimeoutProvider : public CThread { |
| 142 | |
| 143 | private: |
| 144 | |
| 145 | // The timeouts are ordered in the order of which they |
| 146 | // will expire. Nearest in future is first in list. |
| 147 | std::list<TPRequest<TOCommand, TOSubscriber> *> requests; |
| 148 | |
| 149 | CMutexClass synchLock; |
| 150 | CEventClass timeEvent; |
| 151 | |
| 152 | bool stop; // Flag to tell the worker thread |
| 153 | // to terminate. Set to true and |
| 154 | // wake the worker thread to |
| 155 | // terminate it. |
| 156 | |
| 157 | public: |
| 158 | |
| 159 | /** |
| 160 | * Timeout Provide Constructor |
| 161 | */ |
| 162 | TimeoutProvider(): requests(), stop(false) { } |
| 163 | |
| 164 | /** |
| 165 | * Destructor also terminates the Timeout thread. |
| 166 | */ |
| 167 | ~TimeoutProvider() { |
| 168 | stop = true; |
| 169 | timeEvent.Set(); |
| 170 | } |
| 171 | |
| 172 | /** |
| 173 | * Terminates the Timeout provider thread. |
| 174 | */ |
| 175 | void stopThread(){ |
| 176 | stop = true; |
| 177 | timeEvent.Set(); |
| 178 | } |
| 179 | |
| 180 | /** |
| 181 | * Request a timeout trigger. |
| 182 | * |
| 183 | * @param time_ms Number of milli-seconds until the timeout is |
| 184 | * wanted. Note that a small additional period of time is |
| 185 | * added that depends on execution speed. |
| 186 | * @param subscriber The receiver of the callback when the command has timed |
| 187 | * out. This argument must not be NULL. |
| 188 | * @param command Specifies the String command to be passed back in the |
| 189 | * callback. |
| 190 | */ |
| 191 | void requestTimeout(int32_t time_ms, TOSubscriber subscriber, const TOCommand &command) |
| 192 | { |
| 193 | TPRequest<TOCommand, TOSubscriber>* request = |
| 194 | new TPRequest<TOCommand, TOSubscriber>(subscriber, time_ms, command); |
| 195 | |
| 196 | synchLock.Lock(); |
| 197 | |
| 198 | if (requests.size()==0) { |
| 199 | requests.push_front(request); |
| 200 | timeEvent.Set(); |
| 201 | synchLock.Unlock(); |
| 202 | return; |
| 203 | } |
| 204 | if (request->happensBefore(requests.front())) { |
| 205 | requests.push_front(request); |
| 206 | timeEvent.Set(); |
| 207 | synchLock.Unlock(); |
| 208 | return; |
| 209 | } |
| 210 | if (requests.back()->happensBefore(request)){ |
| 211 | requests.push_back(request); |
| 212 | timeEvent.Set(); |
| 213 | synchLock.Unlock(); |
| 214 | return; |
| 215 | } |
| 216 | |
| 217 | typename std::list<TPRequest<TOCommand, TOSubscriber>* >::iterator i; |
| 218 | for(i = requests.begin(); i != requests.end(); i++ ) { |
| 219 | if( request->happensBefore(*i)) { |
| 220 | requests.insert(i, request); |
| 221 | break; |
| 222 | } |
| 223 | } |
| 224 | timeEvent.Set(); |
| 225 | synchLock.Unlock(); |
| 226 | } |
| 227 | |
| 228 | /** |
| 229 | * Removes timeout requests that belong to a subscriber and command. |
| 230 | * |
| 231 | * @see requestTimeout |
| 232 | */ |
| 233 | void cancelRequest(TOSubscriber subscriber, const TOCommand &command) |
| 234 | { |
| 235 | synchLock.Lock(); |
| 236 | typename std::list<TPRequest<TOCommand, TOSubscriber>* >::iterator i; |
| 237 | for(i = requests.begin(); i != requests.end(); ) { |
| 238 | if( (*i)->getCommand() == command && |
| 239 | (*i)->getSubscriber() == subscriber) { |
| 240 | i = requests.erase(i); |
| 241 | continue; |
| 242 | } |
| 243 | i++; |
| 244 | } |
| 245 | synchLock.Unlock(); |
| 246 | } |
| 247 | |
| 248 | virtual BOOL OnTask(LPVOID lpv) |
| 249 | { |
| 250 | do { |
| 251 | synchLock.Lock(); |
| 252 | int32_t time = 3600000; |
| 253 | int32_t size = 0; |
| 254 | |
| 255 | if ((size = requests.size()) > 0) { |
| 256 | time = requests.front()->getMsToTimeout(); |
| 257 | } |
| 258 | if (time == 0 && size > 0) { |
| 259 | TPRequest<TOCommand, TOSubscriber>* req = requests.front(); |
| 260 | TOSubscriber subs = req->getSubscriber(); |
| 261 | TOCommand command = req->getCommand(); |
| 262 | |
| 263 | requests.pop_front(); |
| 264 | if (stop) { // This must be checked so that we will |
| 265 | synchLock.Unlock(); |
| 266 | return FALSE; |
| 267 | } |
| 268 | synchLock.Unlock(); // call the command with free Mutex |
| 269 | |
| 270 | subs->handleTimeout(command); |
| 271 | continue; |
| 272 | } |
| 273 | else |
| 274 | synchLock.Unlock(); |
| 275 | if (stop) { // If we are told to exit while executing cmd |
| 276 | return FALSE; |
| 277 | } |
| 278 | timeEvent.Wait(time); |
| 279 | timeEvent.Reset(); |
| 280 | if (stop) { // If we are told to exit while waiting we will exit |
| 281 | return FALSE; |
| 282 | } |
| 283 | |
| 284 | } while (true); |
| 285 | } |
| 286 | |
| 287 | }; |
| 288 | |
| 289 | #endif |