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/**********
This library is free software; you can redistribute it and/or modify it under
the terms of the GNU Lesser General Public License as published by the
Free Software Foundation; either version 2.1 of the License, or (at your
option) any later version. (See <http://www.gnu.org/copyleft/lesser.html>.)
This library 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 Lesser General Public License for
more details.
You should have received a copy of the GNU Lesser General Public License
along with this library; if not, write to the Free Software Foundation, Inc.,
59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
**********/
// Copyright (c) 1996-2000 Live Networks, Inc. All rights reserved.
// Basic Usage Environment: for a simple, non-scripted, console application
// Implementation
#include "BasicUsageEnvironment0.hh"
#include "HandlerSet.hh"
////////// A subclass of DelayQueueEntry,
////////// used to implement BasicTaskScheduler0::scheduleDelayedTask()
class AlarmHandler: public DelayQueueEntry {
public:
AlarmHandler(TaskFunc* proc, void* clientData, DelayInterval timeToDelay)
: DelayQueueEntry(timeToDelay), fProc(proc), fClientData(clientData) {
}
private: // redefined virtual functions
virtual void handleTimeout() {
(*fProc)(fClientData);
DelayQueueEntry::handleTimeout();
}
private:
TaskFunc* fProc;
void* fClientData;
};
////////// BasicTaskScheduler0 //////////
BasicTaskScheduler0::BasicTaskScheduler0()
: fLastHandledSocketNum(-1) {
fReadHandlers = new HandlerSet;
}
BasicTaskScheduler0::~BasicTaskScheduler0() {
delete fReadHandlers;
}
TaskToken BasicTaskScheduler0::scheduleDelayedTask(int64_t microseconds,
TaskFunc* proc,
void* clientData) {
if (microseconds < 0) microseconds = 0;
DelayInterval timeToDelay((long)(microseconds/1000000), (long)(microseconds%1000000));
AlarmHandler* alarmHandler = new AlarmHandler(proc, clientData, timeToDelay);
fDelayQueue.addEntry(alarmHandler);
return (void*)(alarmHandler->token());
}
void BasicTaskScheduler0::unscheduleDelayedTask(TaskToken& prevTask) {
DelayQueueEntry* alarmHandler = fDelayQueue.removeEntry((long)prevTask);
prevTask = NULL;
delete alarmHandler;
}
void BasicTaskScheduler0::doEventLoop(char* watchVariable) {
// Repeatedly loop, handling readble sockets and timed events:
while (1) {
if (watchVariable != NULL && *watchVariable != 0) break;
SingleStep();
}
}
////////// HandlerSet (etc.) implementation //////////
HandlerDescriptor::HandlerDescriptor(HandlerDescriptor* nextHandler) {
// Link this descriptor into a doubly-linked list:
// (Note that this code works even if "nextHandler == this")
fNextHandler = nextHandler;
fPrevHandler = nextHandler->fPrevHandler;
nextHandler->fPrevHandler = this;
fPrevHandler->fNextHandler = this;
}
HandlerDescriptor::~HandlerDescriptor() {
// Unlink this descriptor from a doubly-linked list:
fNextHandler->fPrevHandler = fPrevHandler;
fPrevHandler->fNextHandler = fNextHandler;
}
HandlerSet::HandlerSet()
: fHandlers(&fHandlers) {
fHandlers.socketNum = -1; // shouldn't ever get looked at, but in case...
}
HandlerSet::~HandlerSet() {
// Delete each handler descriptor:
while (fHandlers.fNextHandler != &fHandlers) {
delete fHandlers.fNextHandler; // changes fHandlers->fNextHandler
}
}
void HandlerSet
::assignHandler(int socketNum,
TaskScheduler::BackgroundHandlerProc* handlerProc,
void* clientData) {
// First, see if there's already a handler for this socket:
HandlerDescriptor* handler;
HandlerIterator iter(*this);
while ((handler = iter.next()) != NULL) {
if (handler->socketNum == socketNum) break;
}
if (handler == NULL) { // No existing handler, so create a new descr:
handler = new HandlerDescriptor(fHandlers.fNextHandler);
handler->socketNum = socketNum;
}
handler->handlerProc = handlerProc;
handler->clientData = clientData;
}
void HandlerSet::removeHandler(int socketNum) {
HandlerDescriptor* handler;
HandlerIterator iter(*this);
while ((handler = iter.next()) != NULL) {
if (handler->socketNum == socketNum) {
delete handler;
break;
}
}
}
HandlerIterator::HandlerIterator(HandlerSet& handlerSet)
: fOurSet(handlerSet) {
reset();
}
HandlerIterator::~HandlerIterator() {
}
void HandlerIterator::reset() {
fNextPtr = fOurSet.fHandlers.fNextHandler;
}
HandlerDescriptor* HandlerIterator::next() {
HandlerDescriptor* result = fNextPtr;
if (result == &fOurSet.fHandlers) { // no more
result = NULL;
} else {
fNextPtr = fNextPtr->fNextHandler;
}
return result;
}
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