commit 7eca418465cf3c74c7aee6dfc9a2ab9ba7fbfcfe from: Florian Westphal date: Thu Jul 07 18:38:35 2005 UTC add new IO layer commit - ebbf92898e749da9341ebe3b7e71b96362161043 commit + 7eca418465cf3c74c7aee6dfc9a2ab9ba7fbfcfe blob - /dev/null blob + efeba72f5a2c8558cc648311168bd5acb9b92feb (mode 644) --- /dev/null +++ src/ngircd/io.c @@ -0,0 +1,611 @@ +/* + * This program 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. + * Please read the file COPYING, README and AUTHORS for more information. + * + * I/O abstraction interface. + * Copyright (c) 2005 Florian Westphal (westphal@foo.fh-furtwangen.de) + * + */ + +#include "portab.h" + +static char UNUSED id[] = "$Id: io.c,v 1.1 2005/07/07 18:38:35 fw Exp $"; + +#include +#include +#include +#include +#include +#include +#include + +#include "array.h" +#include "io.h" +#include "log.h" + + +typedef struct { + void (*callback)(int, short); + int fd; + short what; +} io_event; + +#define INIT_IOEVENT { NULL, -1, 0, NULL } +#define IO_ERROR 4 + +#ifdef HAVE_EPOLL_CREATE +#define IO_USE_EPOLL 1 +#else +# ifdef HAVE_KQUEUE +#define IO_USE_KQUEUE 1 +# else +#define IO_USE_SELECT 1 +#endif +#endif + + +#ifdef IO_USE_EPOLL +#include + +static int io_masterfd; +static bool io_event_new_epoll(int fd, short what); +static bool io_event_change_epoll(int fd, short what); +static int io_dispatch_epoll(struct timeval *tv); +#endif + +#ifdef IO_USE_KQUEUE +#include +#include +static array io_evcache; +static int io_masterfd; + +static int io_dispatch_kqueue(struct timeval *tv); +static bool io_event_add_kqueue(int, short); +#endif + +#ifdef IO_USE_SELECT +#include "defines.h" /* for conn.h */ +#include "conn.h" /* for CONN_IDX (needed by resolve.h) */ +#include "resolve.h" /* for RES_STAT (needed by conf.h) */ +#include "conf.h" /* for Conf_MaxConnections */ + +static fd_set readers; +static fd_set writers; +static int select_maxfd; /* the select() interface sucks badly */ +static int io_dispatch_select(struct timeval *tv); +#endif + +static array io_events; + +static void io_docallback PARAMS((int fd, short what)); + +static io_event * +io_event_get(int fd) +{ + io_event *i; + assert(fd >= 0); + i = (io_event *) array_get(&io_events, sizeof(io_event), fd); + assert(i); + + if (!i) { +#ifdef DEBUG + Log(LOG_DEBUG, "io_event_add(): EMPTY FOR fd %d", fd); +#endif + return NULL; + } + return i; +} + + +bool +io_library_init(unsigned int eventsize) +{ +#ifdef IO_USE_EPOLL + int ecreate_hint = (int)eventsize; + if (ecreate_hint <= 0) + ecreate_hint = 128; +#endif + +#ifdef IO_USE_SELECT +#ifdef FD_SETSIZE + if (eventsize >= FD_SETSIZE) + eventsize = FD_SETSIZE - 1; +#endif +#endif + if (eventsize && !array_alloc(&io_events, sizeof(io_event), eventsize)) + eventsize = 0; + +#ifdef IO_USE_EPOLL + io_masterfd = epoll_create(ecreate_hint); + Log(LOG_INFO, + "io subsystem: using epoll (hint size %d), initial io_event maxfd: %u, io_masterfd %d", + ecreate_hint, eventsize, io_masterfd); + return io_masterfd >= 0; +#endif +#ifdef IO_USE_SELECT + Log(LOG_INFO, "io subsystem: using select, initial io_event maxfd: %u", + eventsize); + FD_ZERO(&readers); + FD_ZERO(&writers); +#ifdef FD_SETSIZE + if (Conf_MaxConnections >= FD_SETSIZE) { + Log(LOG_WARNING, + "Conf_MaxConnections (%d) exceeds limit (%u), changed Conf_MaxConnections to %u", + Conf_MaxConnections, FD_SETSIZE, FD_SETSIZE - 1); + + Conf_MaxConnections = FD_SETSIZE - 1; + } +#else + Log(LOG_WARNING, + "FD_SETSIZE undefined, don't know how many descriptors select() can handle on your platform"); +#endif + return true; +#endif +#ifdef IO_USE_KQUEUE + io_masterfd = kqueue(); + + Log(LOG_INFO, + "io subsystem: using kqueue, initial io_event maxfd: %u, io_masterfd %d", + eventsize, io_masterfd); + return io_masterfd >= 0; +#endif +} + + +bool +io_library_shutdown(void) +{ + unsigned int len = array_length(&io_events, sizeof(io_event)); + + while (len--) { + if (NULL == io_event_get(len)) + continue; + } +#ifndef IO_USE_SELECT + close(io_masterfd); /* kqueue, epoll */ + io_masterfd = -1; +#else + FD_ZERO(&readers); + FD_ZERO(&writers); +#endif +#ifdef IO_USE_KQUEUE + array_free(&io_evcache); +#endif + return true; +} + + +bool +io_event_setcb(int fd, void (*cbfunc) (int, short)) +{ + io_event *i = io_event_get(fd); + if (!i) + return false; + + i->callback = cbfunc; + return true; +} + + +bool +io_event_create(int fd, short what, void (*cbfunc) (int, short)) +{ + io_event *i; + + assert(fd >= 0); + +#ifdef IO_USE_SELECT +#ifdef FD_SETSIZE + if (fd >= FD_SETSIZE) { + Log(LOG_ERR, + "fd %d exceeds FD_SETSIZE (%u) (select can't handle more file descriptors)", + fd, FD_SETSIZE); + return false; + } +#endif /* FD_SETSIZE */ +#endif /* IO_USE_SELECT */ + + i = (io_event *) array_alloc(&io_events, sizeof(io_event), fd); + if (!i) { + Log(LOG_WARNING, + "array_alloc failed: could not allocate space for %d io_event structures", + fd); + return false; + } + + i->fd = fd; + i->callback = cbfunc; +#ifdef IO_USE_EPOLL + i->what = what; + return io_event_new_epoll(fd, what); +#endif +#ifdef IO_USE_KQUEUE + i->what = what; + return io_event_add_kqueue(fd, what); +#endif +#ifdef IO_USE_SELECT + i->what = 0; + return io_event_add(fd, what); +#endif +} + + +#ifdef IO_USE_EPOLL +static bool +io_event_new_epoll(int fd, short what) +{ + struct epoll_event ev = { 0, {0} }; + ev.data.fd = fd; + + if (what & IO_WANTREAD) + ev.events = EPOLLIN | EPOLLPRI; + if (what & IO_WANTWRITE) + ev.events |= EPOLLOUT; + + return epoll_ctl(io_masterfd, EPOLL_CTL_ADD, fd, &ev) == 0; +} + + +static bool +io_event_change_epoll(int fd, short what) +{ + struct epoll_event ev = { 0, {0} }; + ev.data.fd = fd; + + if (what & IO_WANTREAD) + ev.events = EPOLLIN | EPOLLPRI; + if (what & IO_WANTWRITE) + ev.events |= EPOLLOUT; + + return epoll_ctl(io_masterfd, EPOLL_CTL_MOD, fd, &ev) == 0; +} +#endif + +#ifdef IO_USE_KQUEUE +static bool +io_event_kqueue_commit_cache(void) +{ + struct kevent *events; + bool ret; + int len = (int) array_length(&io_evcache, sizeof (struct kevent)); + + if (!len) /* nothing to do */ + return true; + + assert(len>0); + + if (len < 0) { + array_free(&io_evcache); + return false; + } + + events = array_start(&io_evcache); + + assert(events); + + ret = kevent(io_masterfd, events, len, NULL, 0, NULL) == 0; + if (ret) + array_trunc(&io_evcache); + return ret; +} + + +static bool +io_event_add_kqueue(int fd, short what) +{ + struct kevent kev; + short filter = 0; + unsigned int len = array_length(&io_evcache, sizeof kev); + bool ret; + + if (what & IO_WANTREAD) + filter = EVFILT_READ; + + if (what & IO_WANTWRITE) + filter |= EVFILT_WRITE; + + if (len >= 100) { + ret = io_event_kqueue_commit_cache(); + if (ret) + array_trunc(&io_evcache); + } + + EV_SET(&kev, fd, filter, EV_ADD | EV_ENABLE, 0, 0, NULL); + return array_catb(&io_evcache, (char*) &kev, sizeof (kev)); +} +#endif + + +bool +io_event_add(int fd, short what) +{ + io_event *i = io_event_get(fd); + + assert(i); + + if (!i) + return false; + if (i->what == what) + return true; +#ifdef DEBUG + Log(LOG_DEBUG, "io_event_add(): fd %d (arg: %d), what %d.", i->fd, fd, + what); +#endif + + i->what |= what; + +#ifdef IO_USE_EPOLL + return io_event_change_epoll(fd, i->what); +#endif + +#ifdef IO_USE_KQUEUE + return io_event_add_kqueue(fd, what); +#endif + +#ifdef IO_USE_SELECT + if (fd > select_maxfd) + select_maxfd = fd; + + if (what & IO_WANTREAD) + FD_SET(fd, &readers); + if (what & IO_WANTWRITE) + FD_SET(fd, &writers); + + return true; +#endif +} + + +bool +io_setnonblock(int fd) +{ + int flags = fcntl(fd, F_GETFL); + if (flags == -1) + return false; + +#ifndef O_NONBLOCK +#define O_NONBLOCK O_NDELAY +#endif + flags |= O_NONBLOCK; + + return fcntl(fd, F_SETFL, flags) == 0; +} + + +bool +io_close(int fd) +{ + io_event *i = io_event_get(fd); + if (i) { + memset(i, 0, sizeof(io_event)); + i->fd = -1; + } +#ifdef IO_USE_SELECT + FD_CLR(fd, &writers); + FD_CLR(fd, &readers); + + if (fd == select_maxfd) + select_maxfd--; +#endif +#ifdef IO_USE_KQUEUE + if (array_length(&io_evcache, sizeof (struct kevent))) /* pending data in cache? */ + io_event_kqueue_commit_cache(); +#endif + return close(fd) == 0; /* both epoll an kqueue will remove fd from all sets automatically */ +} + + +bool +io_event_del(int fd, short what) +{ +#ifdef IO_USE_KQUEUE + struct kevent kev; + short filter = 0; +#endif + io_event *i = io_event_get(fd); +#ifdef DEBUG + Log(LOG_DEBUG, "io_event_del(): trying to delete eventtype %d on fd %d", + what, fd); +#endif + assert(i); + if (!i) + return true; + + i->what &= ~what; + +#ifdef IO_USE_EPOLL + return io_event_change_epoll(fd, i->what); +#endif + +#ifdef IO_USE_KQUEUE + if (what & IO_WANTREAD) + filter = EVFILT_READ; + + if (what & IO_WANTWRITE) + filter |= EVFILT_WRITE; + + EV_SET(&kev, fd, filter, EV_DELETE, 0, 0, NULL); + return kevent(io_masterfd, &kev, 1, NULL, 0, NULL) == 0; +#endif + +#ifdef IO_USE_SELECT + if (what & IO_WANTWRITE) + FD_CLR(i->fd, &writers); + + if (what & IO_WANTREAD) + FD_CLR(i->fd, &readers); + + return true; +#endif +} + + +#ifdef IO_USE_SELECT +static int +io_dispatch_select(struct timeval *tv) +{ + fd_set readers_tmp = readers; + fd_set writers_tmp = writers; + short what; + int ret, i; + int fds_ready; + ret = select(select_maxfd + 1, &readers_tmp, &writers_tmp, NULL, tv); + if (ret <= 0) + return ret; + + fds_ready = ret; + + for (i = 0; i <= select_maxfd; i++) { + what = 0; + if (FD_ISSET(i, &readers_tmp)) { + what = IO_WANTREAD; + fds_ready--; + } + + if (FD_ISSET(i, &writers_tmp)) { + what |= IO_WANTWRITE; + fds_ready--; + } + if (what) + io_docallback(i, what); + if (fds_ready <= 0) + break; + } + + return ret; +} +#endif + + +#ifdef IO_USE_EPOLL +static int +io_dispatch_epoll(struct timeval *tv) +{ + time_t sec = tv->tv_sec * 1000; + int i, total = 0, ret, timeout = tv->tv_usec + sec; + struct epoll_event epoll_ev[100]; + short type; + + if (timeout < 0) + timeout = 1000; + + do { + ret = epoll_wait(io_masterfd, epoll_ev, 100, timeout); + total += ret; + if (ret <= 0) + return total; + + for (i = 0; i < ret; i++) { + type = 0; + if (epoll_ev[i].events & (EPOLLERR | EPOLLHUP)) + type = IO_ERROR; + + if (epoll_ev[i].events & (EPOLLIN | EPOLLPRI)) + type |= IO_WANTREAD; + + if (epoll_ev[i].events & EPOLLOUT) + type |= IO_WANTWRITE; + + io_docallback(epoll_ev[i].data.fd, type); + } + + timeout = 0; + } while (ret == 100); + + return total; +} +#endif + + +#ifdef IO_USE_KQUEUE +static int +io_dispatch_kqueue(struct timeval *tv) +{ + int i, total = 0, ret; + struct kevent kev[100]; + struct kevents *newevents; + struct timespec ts; + int newevents_len; + short type; + ts.tv_sec = tv->tv_sec; + ts.tv_nsec = tv->tv_usec * 1000; + + do { + newevents_len = array_length(&io_evcache, sizeof (struct kevent)); + newevents = (newevents_len > 0) ? array_start(&io_evcache) : NULL; + assert(newevents_len >= 0); + if (newevents_len < 0) + newevents_len = 0; +#ifdef DEBUG + if (newevents_len) + assert(newevents); +#endif + + ret = kevent(io_masterfd, newevents, newevents_len, kev, 100, &ts); + if ((newevents_len>0) && ret != -1) + array_trunc(&io_evcache); + + total += ret; + if (ret <= 0) + return total; + + for (i = 0; i < ret; i++) { + type = 0; + if (kev[i].flags & EV_EOF) + type = IO_ERROR; + + if (kev[i].filter & EV_ERROR) + type = IO_ERROR; + + if (kev[i].filter & EVFILT_READ) + type |= IO_WANTREAD; + + if (kev[i].filter & EVFILT_WRITE) + type |= IO_WANTWRITE; + + io_docallback(kev[i].ident, type); + } + + ts.tv_sec = 0; + ts.tv_nsec = 0; + + } while (ret == 100); + + return total; +} +#endif + + +int +io_dispatch(struct timeval *tv) +{ +#ifdef IO_USE_SELECT + return io_dispatch_select(tv); +#endif +#ifdef IO_USE_KQUEUE + return io_dispatch_kqueue(tv); +#endif +#ifdef IO_USE_EPOLL + return io_dispatch_epoll(tv); +#endif +} + + +/* call the callback function inside the struct matching fd */ +static void +io_docallback(int fd, short what) +{ + io_event *i; +#ifdef DEBUG + Log(LOG_DEBUG, "doing callback for fd %d, what %d", fd, what); +#endif + i = io_event_get(fd); + assert(i); + + if (i->callback) /* callback might be 0 if previous callback function called io_close on this fd */ + i->callback(fd, (what & IO_ERROR) ? i->what : what); + /* if error indicator is set, we return the event(s) the app asked for */ +} blob - /dev/null blob + 3890bcc7df8111ead63749b1c1d844e1dde22e7c (mode 644) --- /dev/null +++ src/ngircd/io.h @@ -0,0 +1,50 @@ +/* + * This program 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. + * Please read the file COPYING, README and AUTHORS for more information. + * + * I/O abstraction interface header + * + * $Id: io.h,v 1.1 2005/07/07 18:38:35 fw Exp $ + */ + +#ifndef io_H_inclucded +#define io_H_included + +#include "portab.h" +#include + +#define IO_WANTREAD 1 +#define IO_WANTWRITE 2 + +/* init library. sets up epoll/kqueue descriptors and tries to allocate space for ioevlen file descriptors. + ioevlen is just the _initial_ size, not a limit. */ +bool io_library_init PARAMS((unsigned int ioevlen)); + +/* shutdown and free all internal data structures */ +bool io_library_shutdown PARAMS((void)); + +/* add fd to internal set, enable readability check, set callback */ +bool io_event_create PARAMS((int fd, short what, void (*cbfunc)(int, short))); + +/* change callback function associated with fd */ +bool io_event_setcb PARAMS((int fd, void (*cbfunc)(int, short))); + +/* watch fd for event of type what */ +bool io_event_add PARAMS((int fd, short what)); + +/* do not watch fd for event of type what */ +bool io_event_del PARAMS((int fd, short what)); + +/* remove fd from watchlist, close() fd. */ +bool io_close PARAMS((int fd)); + +/* set O_NONBLOCK */ +bool io_setnonblock PARAMS((int fd)); + +/* watch fds for activity */ +int io_dispatch PARAMS((struct timeval *tv)); + +#endif /* io_H_included */