Artifact f08643e4a067bd46a97296497769db7b44375c8aa3f5321b1335bccb9ca4585d:
- File
src/OFKernelEventObserver_epoll.m
— part of check-in
[b84490ab4f]
at
2016-03-20 12:05:46
on branch 0.8
— Never block when the read buffer is non-empty
This was broken by 88f2f03. The problem only existed when something was
in the read buffer, but not processed completely, as after processing
the read buffer, it would go on to wait for data - but since not the
entire read buffer had been processed, it meant there was still data
left there that needed to be handled first. (user: js, size: 6113) [annotate] [blame] [check-ins using]
/* * Copyright (c) 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016 * Jonathan Schleifer <js@heap.zone> * * All rights reserved. * * This file is part of ObjFW. It may be distributed under the terms of the * Q Public License 1.0, which can be found in the file LICENSE.QPL included in * the packaging of this file. * * Alternatively, it may be distributed under the terms of the GNU General * Public License, either version 2 or 3, which can be found in the file * LICENSE.GPLv2 or LICENSE.GPLv3 respectively included in the packaging of this * file. */ #include "config.h" #include <assert.h> #include <errno.h> #include <fcntl.h> #include <unistd.h> #include <sys/epoll.h> #import "OFKernelEventObserver.h" #import "OFKernelEventObserver+Private.h" #import "OFKernelEventObserver_epoll.h" #import "OFArray.h" #import "OFMapTable.h" #import "OFNull.h" #ifdef OF_HAVE_THREADS # import "OFMutex.h" #endif #import "OFInitializationFailedException.h" #import "OFObserveFailedException.h" #define EVENTLIST_SIZE 64 static const of_map_table_functions_t mapFunctions = { NULL }; @implementation OFKernelEventObserver_epoll - init { self = [super init]; @try { struct epoll_event event; #ifdef HAVE_EPOLL_CREATE1 if ((_epfd = epoll_create1(EPOLL_CLOEXEC)) == -1) @throw [OFInitializationFailedException exception]; #else int flags; if ((_epfd = epoll_create(1)) == -1) @throw [OFInitializationFailedException exception]; if ((flags = fcntl(_epfd, F_GETFD, 0)) != -1) fcntl(_epfd, F_SETFD, flags | FD_CLOEXEC); #endif _FDToEvents = [[OFMapTable alloc] initWithKeyFunctions: mapFunctions valueFunctions: mapFunctions]; memset(&event, 0, sizeof(event)); event.events = EPOLLIN; event.data.ptr = [OFNull null]; if (epoll_ctl(_epfd, EPOLL_CTL_ADD, _cancelFD[0], &event) == -1) @throw [OFInitializationFailedException exception]; } @catch (id e) { [self release]; @throw e; } return self; } - (void)dealloc { close(_epfd); [_FDToEvents release]; [super dealloc]; } - (void)OF_addObject: (id)object fileDescriptor: (int)fd events: (int)addEvents objectsArray: (OFMutableArray*)objectsArray { #ifdef OF_HAVE_THREADS [_mutex lock]; @try { #endif struct epoll_event event; intptr_t events; events = (intptr_t)[_FDToEvents valueForKey: (void*)(intptr_t)fd]; memset(&event, 0, sizeof(event)); event.events = (int)events | addEvents; event.data.ptr = object; [objectsArray addObject: object]; if (epoll_ctl(_epfd, (events == 0 ? EPOLL_CTL_ADD : EPOLL_CTL_MOD), fd, &event) == -1) { [objectsArray removeObjectIdenticalTo: object]; @throw [OFObserveFailedException exceptionWithObserver: self errNo: errno]; } [_FDToEvents setValue: (void*)(events | addEvents) forKey: (void*)(intptr_t)fd]; #ifdef OF_HAVE_THREADS } @finally { [_mutex unlock]; } #endif } - (void)OF_removeObject: (id)object fileDescriptor: (int)fd events: (int)removeEvents objectsArray: (OFMutableArray*)objectsArray { #ifdef OF_HAVE_THREADS [_mutex lock]; @try { #endif intptr_t events; events = (intptr_t)[_FDToEvents valueForKey: (void*)(intptr_t)fd]; events &= ~removeEvents; if (events == 0) { if (epoll_ctl(_epfd, EPOLL_CTL_DEL, fd, NULL) == -1) @throw [OFObserveFailedException exceptionWithObserver: self errNo: errno]; [_FDToEvents removeValueForKey: (void*)(intptr_t)fd]; } else { struct epoll_event event; memset(&event, 0, sizeof(event)); event.events = (int)events; event.data.ptr = object; if (epoll_ctl(_epfd, EPOLL_CTL_MOD, fd, &event) == -1) @throw [OFObserveFailedException exceptionWithObserver: self errNo: errno]; [_FDToEvents setValue: (void*)events forKey: (void*)(intptr_t)fd]; } [objectsArray removeObjectIdenticalTo: object]; #ifdef OF_HAVE_THREADS } @finally { [_mutex unlock]; } #endif } - (void)addObjectForReading: (id <OFReadyForReadingObserving>)object { [self OF_addObject: object fileDescriptor: [object fileDescriptorForReading] events: EPOLLIN objectsArray: _readObjects]; } - (void)addObjectForWriting: (id <OFReadyForWritingObserving>)object { [self OF_addObject: object fileDescriptor: [object fileDescriptorForWriting] events: EPOLLOUT objectsArray: _writeObjects]; } - (void)removeObjectForReading: (id <OFReadyForReadingObserving>)object { [self OF_removeObject: object fileDescriptor: [object fileDescriptorForReading] events: EPOLLIN objectsArray: _readObjects]; } - (void)removeObjectForWriting: (id <OFReadyForWritingObserving>)object { [self OF_removeObject: object fileDescriptor: [object fileDescriptorForWriting] events: EPOLLOUT objectsArray: _writeObjects]; } - (void)observeForTimeInterval: (of_time_interval_t)timeInterval { OFNull *nullObject = [OFNull null]; struct epoll_event eventList[EVENTLIST_SIZE]; int i, events; if ([self OF_processReadBuffers]) return; events = epoll_wait(_epfd, eventList, EVENTLIST_SIZE, (timeInterval != -1 ? timeInterval * 1000 : -1)); if (events < 0) @throw [OFObserveFailedException exceptionWithObserver: self errNo: errno]; for (i = 0; i < events; i++) { if (eventList[i].data.ptr == nullObject) { char buffer; assert(eventList[i].events == EPOLLIN); OF_ENSURE(read(_cancelFD[0], &buffer, 1) == 1); continue; } if (eventList[i].events & EPOLLIN) { pool = objc_autoreleasePoolPush(); if ([_delegate respondsToSelector: @selector(objectIsReadyForReading:)]) [_delegate objectIsReadyForReading: eventList[i].data.ptr]; objc_autoreleasePoolPop(pool); } if (eventList[i].events & EPOLLOUT) { pool = objc_autoreleasePoolPush(); if ([_delegate respondsToSelector: @selector(objectIsReadyForWriting:)]) [_delegate objectIsReadyForWriting: eventList[i].data.ptr]; objc_autoreleasePoolPop(pool); } assert((eventList[i].events & ~(EPOLLIN | EPOLLOUT)) == 0); } } @end