From bdf5651f1db8a40f744f378896dc33eb7f58fa50 Mon Sep 17 00:00:00 2001 From: Constantin Kaplinsky Date: Mon, 17 Apr 2006 01:32:35 +0000 Subject: [PATCH] Two new files from VNC 4.1.1 that were overlooked on merging. git-svn-id: svn://svn.code.sf.net/p/tigervnc/code/branches/merge-with-vnc-4.1.1@524 3789f03b-4d11-0410-bbf8-ca57d06f2519 --- rfb/Timer.cxx | 174 ++++++++++++++++++++++++++++++++++++++++++++++++++ rfb/Timer.h | 102 +++++++++++++++++++++++++++++ 2 files changed, 276 insertions(+) create mode 100644 rfb/Timer.cxx create mode 100644 rfb/Timer.h diff --git a/rfb/Timer.cxx b/rfb/Timer.cxx new file mode 100644 index 00000000..59d250ed --- /dev/null +++ b/rfb/Timer.cxx @@ -0,0 +1,174 @@ +/* Copyright (C) 2002-2005 RealVNC Ltd. All Rights Reserved. + * + * This 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 2 of the License, or + * (at your option) any later version. + * + * This software 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 software; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, + * USA. + */ + +// -=- Timer.cxx + +#include +#ifdef WIN32 +#include +#ifndef _WIN32_WCE +#include +#endif +#endif +#include +#include +#include + +using namespace rfb; + +#ifndef __NO_DEFINE_VLOG__ +static LogWriter vlog("Timer"); +#endif + + +// Win32 does not provide gettimeofday, so we emulate it to simplify the +// Timer code. + +#ifdef _WIN32 +static void gettimeofday(struct timeval* tv, void*) +{ + LARGE_INTEGER counts, countsPerSec; + static double usecPerCount = 0.0; + + if (QueryPerformanceCounter(&counts)) { + if (usecPerCount == 0.0) { + QueryPerformanceFrequency(&countsPerSec); + usecPerCount = 1000000.0 / countsPerSec.QuadPart; + } + + LONGLONG usecs = (LONGLONG)(counts.QuadPart * usecPerCount); + tv->tv_usec = (long)(usecs % 1000000); + tv->tv_sec = (long)(usecs / 1000000); + + } else { +#ifndef _WIN32_WCE + struct timeb tb; + ftime(&tb); + tv->tv_sec = tb.time; + tv->tv_usec = tb.millitm * 1000; +#else + throw SystemException("QueryPerformanceCounter", GetLastError()); +#endif + } +} +#endif + + +// Millisecond timeout processing helper functions + +inline static timeval addMillis(timeval inTime, int millis) { + int secs = millis / 1000; + millis = millis % 1000; + inTime.tv_sec += secs; + inTime.tv_usec += millis * 1000; + if (inTime.tv_usec >= 1000000) { + inTime.tv_sec++; + inTime.tv_usec -= 1000000; + } + return inTime; +} + +inline static int diffTimeMillis(timeval later, timeval earlier) { + return ((later.tv_sec - earlier.tv_sec) * 1000) + ((later.tv_usec - earlier.tv_usec) / 1000); +} + +std::list Timer::pending; + +int Timer::checkTimeouts() { + if (pending.empty()) + return 0; + timeval now; + gettimeofday(&now, 0); + while (pending.front()->isBefore(now)) { + Timer* timer = pending.front(); + pending.pop_front(); + vlog.debug("handleTimeout(%p)", timer); + if (timer->cb->handleTimeout(timer)) { + timer->dueTime = addMillis(timer->dueTime, timer->timeoutMs); + if (timer->isBefore(now)) { + // Time has jumped forwards! + vlog.info("time has moved forwards!"); + timer->dueTime = addMillis(now, timer->timeoutMs); + } + insertTimer(timer); + } else if (pending.empty()) { + return 0; + } + } + return getNextTimeout(); +} + +int Timer::getNextTimeout() { + timeval now; + gettimeofday(&now, 0); + int toWait = __rfbmax(1, diffTimeMillis(pending.front()->dueTime, now)); + if (toWait > pending.front()->timeoutMs) { + if (toWait - pending.front()->timeoutMs < 1000) { + vlog.info("gettimeofday is broken..."); + return toWait; + } + // Time has jumped backwards! + vlog.info("time has moved backwards!"); + pending.front()->dueTime = now; + toWait = 1; + } + return toWait; +} + +void Timer::insertTimer(Timer* t) { + std::list::iterator i; + for (i=pending.begin(); i!=pending.end(); i++) { + if (t->isBefore((*i)->dueTime)) { + pending.insert(i, t); + return; + } + } + pending.push_back(t); +} + +void Timer::start(int timeoutMs_) { + timeval now; + gettimeofday(&now, 0); + stop(); + timeoutMs = timeoutMs_; + dueTime = addMillis(now, timeoutMs); + insertTimer(this); +} + +void Timer::stop() { + pending.remove(this); +} + +bool Timer::isStarted() { + std::list::iterator i; + for (i=pending.begin(); i!=pending.end(); i++) { + if (*i == this) + return true; + } + return false; +} + +int Timer::getTimeoutMs() { + return timeoutMs; +} + +bool Timer::isBefore(timeval other) { + return (dueTime.tv_sec < other.tv_sec) || + ((dueTime.tv_sec == other.tv_sec) && + (dueTime.tv_usec < other.tv_usec)); +} diff --git a/rfb/Timer.h b/rfb/Timer.h new file mode 100644 index 00000000..e295b826 --- /dev/null +++ b/rfb/Timer.h @@ -0,0 +1,102 @@ +/* Copyright (C) 2002-2005 RealVNC Ltd. All Rights Reserved. + * + * This 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 2 of the License, or + * (at your option) any later version. + * + * This software 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 software; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, + * USA. + */ + +#ifndef __RFB_TIMER_H__ +#define __RFB_TIMER_H__ + +#include +#ifdef WIN32 +#include +#else +#include +#endif + +namespace rfb { + + /* Timer + + Cross-platform timeout handling. The caller creates instances of Timer and passes a + Callback implementation to each. The Callback will then be called with a pointer to + the Timer instance that timed-out when the timeout occurs. + + The static methods of Timer are used by the main loop of the application both to + dispatch elapsed Timer callbacks and to determine how long to wait in select() for + the next timeout to occur. + + */ + + struct Timer { + + struct Callback { + // handleTimeout + // Passed a pointer to the Timer that has timed out. If the handler returns true + // then the Timer is reset and left running, causing another timeout after the + // appropriate interval. + // If the handler returns false then the Timer is cancelled. + virtual bool handleTimeout(Timer* t) = 0; + }; + + // checkTimeouts() + // Dispatches any elapsed Timers, and returns the number of milliseconds until the + // next Timer will timeout. + static int checkTimeouts(); + + // getNextTimeout() + // Returns the number of milliseconds until the next timeout, without dispatching + // any elapsed Timers. + static int getNextTimeout(); + + // Create a Timer with the specified callback handler + Timer(Callback* cb_) {cb = cb_;} + ~Timer() {stop();} + + // startTimer + // Starts the timer, causing a timeout after the specified number of milliseconds. + // If the timer is already active then it will be implicitly cancelled and re-started. + void start(int timeoutMs_); + + // stopTimer + // Cancels the timer. + void stop(); + + // isStarted + // Determines whether the timer is started. + bool isStarted(); + + // getTimeoutMs + // Determines the previously used timeout value, if any. + // Usually used with isStarted() to get the _current_ timeout. + int getTimeoutMs(); + + // isBefore + // Determine whether the Timer will timeout before the specified time. + bool isBefore(timeval other); + + protected: + timeval dueTime; + int timeoutMs; + Callback* cb; + + static void insertTimer(Timer* t); + // The list of currently active Timers, ordered by time left until timeout. + static std::list pending; + }; + +}; + +#endif -- 2.39.5