/* * Copyright (c) 2007 Marc Alexander Lehmann * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions are * met: * * * Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * * Redistributions in binary form must reproduce the above * copyright notice, this list of conditions and the following * disclaimer in the documentation and/or other materials provided * with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #ifndef HAVE_MONOTONIC # ifdef CLOCK_MONOTONIC # define HAVE_MONOTONIC 1 # endif #endif #ifndef HAVE_SELECT # define HAVE_SELECT 1 #endif #ifndef HAVE_EPOLL # define HAVE_EPOLL 0 #endif #ifndef HAVE_REALTIME # define HAVE_REALTIME 1 /* posix requirement, but might be slower */ #endif #define MIN_TIMEJUMP 1. /* minimum timejump that gets detected (if monotonic clock available) */ #define MAX_BLOCKTIME 60. #define PID_HASHSIZE 16 /* size of pid hahs table, must be power of two */ #include "ev.h" typedef struct ev_watcher *W; typedef struct ev_watcher_list *WL; typedef struct ev_watcher_time *WT; static ev_tstamp now, diff; /* monotonic clock */ ev_tstamp ev_now; int ev_method; static int have_monotonic; /* runtime */ static ev_tstamp method_fudge; /* stupid epoll-returns-early bug */ static void (*method_modify)(int fd, int oev, int nev); static void (*method_poll)(ev_tstamp timeout); /*****************************************************************************/ ev_tstamp ev_time (void) { #if HAVE_REALTIME struct timespec ts; clock_gettime (CLOCK_REALTIME, &ts); return ts.tv_sec + ts.tv_nsec * 1e-9; #else struct timeval tv; gettimeofday (&tv, 0); return tv.tv_sec + tv.tv_usec * 1e-6; #endif } static ev_tstamp get_clock (void) { #if HAVE_MONOTONIC if (have_monotonic) { struct timespec ts; clock_gettime (CLOCK_MONOTONIC, &ts); return ts.tv_sec + ts.tv_nsec * 1e-9; } #endif return ev_time (); } #define array_needsize(base,cur,cnt,init) \ if ((cnt) > cur) \ { \ int newcnt = cur; \ do \ { \ newcnt = (newcnt << 1) | 4 & ~3; \ } \ while ((cnt) > newcnt); \ \ base = realloc (base, sizeof (*base) * (newcnt)); \ init (base + cur, newcnt - cur); \ cur = newcnt; \ } /*****************************************************************************/ typedef struct { struct ev_io *head; int events; } ANFD; static ANFD *anfds; static int anfdmax; static void anfds_init (ANFD *base, int count) { while (count--) { base->head = 0; base->events = EV_NONE; ++base; } } typedef struct { W w; int events; } ANPENDING; static ANPENDING *pendings; static int pendingmax, pendingcnt; static void event (W w, int events) { if (w->active) { w->pending = ++pendingcnt; array_needsize (pendings, pendingmax, pendingcnt, ); pendings [pendingcnt - 1].w = w; pendings [pendingcnt - 1].events = events; } } static void queue_events (W *events, int eventcnt, int type) { int i; for (i = 0; i < eventcnt; ++i) event (events [i], type); } static void fd_event (int fd, int events) { ANFD *anfd = anfds + fd; struct ev_io *w; for (w = anfd->head; w; w = w->next) { int ev = w->events & events; if (ev) event ((W)w, ev); } } /*****************************************************************************/ static int *fdchanges; static int fdchangemax, fdchangecnt; static void fd_reify (void) { int i; for (i = 0; i < fdchangecnt; ++i) { int fd = fdchanges [i]; ANFD *anfd = anfds + fd; struct ev_io *w; int events = 0; for (w = anfd->head; w; w = w->next) events |= w->events; anfd->events &= ~EV_REIFY; if (anfd->events != events) { method_modify (fd, anfd->events, events); anfd->events = events; } } fdchangecnt = 0; } static void fd_change (int fd) { if (anfds [fd].events & EV_REIFY) return; anfds [fd].events |= EV_REIFY; ++fdchangecnt; array_needsize (fdchanges, fdchangemax, fdchangecnt, ); fdchanges [fdchangecnt - 1] = fd; } /* called on EBADF to verify fds */ static void fd_recheck (void) { int fd; for (fd = 0; fd < anfdmax; ++fd) if (anfds [fd].events) if (fcntl (fd, F_GETFD) == -1 && errno == EBADF) while (anfds [fd].head) { event ((W)anfds [fd].head, EV_ERROR); evio_stop (anfds [fd].head); } } /*****************************************************************************/ static struct ev_timer **timers; static int timermax, timercnt; static struct ev_periodic **periodics; static int periodicmax, periodiccnt; static void upheap (WT *timers, int k) { WT w = timers [k]; while (k && timers [k >> 1]->at > w->at) { timers [k] = timers [k >> 1]; timers [k]->active = k + 1; k >>= 1; } timers [k] = w; timers [k]->active = k + 1; } static void downheap (WT *timers, int N, int k) { WT w = timers [k]; while (k < (N >> 1)) { int j = k << 1; if (j + 1 < N && timers [j]->at > timers [j + 1]->at) ++j; if (w->at <= timers [j]->at) break; timers [k] = timers [j]; timers [k]->active = k + 1; k = j; } timers [k] = w; timers [k]->active = k + 1; } /*****************************************************************************/ typedef struct { struct ev_signal *head; sig_atomic_t gotsig; } ANSIG; static ANSIG *signals; static int signalmax; static int sigpipe [2]; static sig_atomic_t gotsig; static struct ev_io sigev; static void signals_init (ANSIG *base, int count) { while (count--) { base->head = 0; base->gotsig = 0; ++base; } } static void sighandler (int signum) { signals [signum - 1].gotsig = 1; if (!gotsig) { gotsig = 1; write (sigpipe [1], &gotsig, 1); } } static void sigcb (struct ev_io *iow, int revents) { struct ev_signal *w; int sig; gotsig = 0; read (sigpipe [0], &revents, 1); for (sig = signalmax; sig--; ) if (signals [sig].gotsig) { signals [sig].gotsig = 0; for (w = signals [sig].head; w; w = w->next) event ((W)w, EV_SIGNAL); } } static void siginit (void) { fcntl (sigpipe [0], F_SETFD, FD_CLOEXEC); fcntl (sigpipe [1], F_SETFD, FD_CLOEXEC); /* rather than sort out wether we really need nb, set it */ fcntl (sigpipe [0], F_SETFL, O_NONBLOCK); fcntl (sigpipe [1], F_SETFL, O_NONBLOCK); evio_set (&sigev, sigpipe [0], EV_READ); evio_start (&sigev); } /*****************************************************************************/ static struct ev_idle **idles; static int idlemax, idlecnt; static struct ev_prepare **prepares; static int preparemax, preparecnt; static struct ev_check **checks; static int checkmax, checkcnt; /*****************************************************************************/ static struct ev_child *childs [PID_HASHSIZE]; static struct ev_signal childev; #ifndef WCONTINUED # define WCONTINUED 0 #endif static void childcb (struct ev_signal *sw, int revents) { struct ev_child *w; int pid, status; while ((pid = waitpid (-1, &status, WNOHANG | WUNTRACED | WCONTINUED)) != -1) for (w = childs [pid & (PID_HASHSIZE - 1)]; w; w = w->next) if (w->pid == pid || w->pid == -1) { w->status = status; event ((W)w, EV_CHILD); } } /*****************************************************************************/ #if HAVE_EPOLL # include "ev_epoll.c" #endif #if HAVE_SELECT # include "ev_select.c" #endif int ev_version_major (void) { return EV_VERSION_MAJOR; } int ev_version_minor (void) { return EV_VERSION_MINOR; } int ev_init (int flags) { if (!ev_method) { #if HAVE_MONOTONIC { struct timespec ts; if (!clock_gettime (CLOCK_MONOTONIC, &ts)) have_monotonic = 1; } #endif ev_now = ev_time (); now = get_clock (); diff = ev_now - now; if (pipe (sigpipe)) return 0; ev_method = EVMETHOD_NONE; #if HAVE_EPOLL if (ev_method == EVMETHOD_NONE) epoll_init (flags); #endif #if HAVE_SELECT if (ev_method == EVMETHOD_NONE) select_init (flags); #endif if (ev_method) { evw_init (&sigev, sigcb); siginit (); evsignal_init (&childev, childcb, SIGCHLD); evsignal_start (&childev); } } return ev_method; } /*****************************************************************************/ void ev_prefork (void) { /* nop */ } void ev_postfork_parent (void) { /* nop */ } void ev_postfork_child (void) { #if HAVE_EPOLL if (ev_method == EVMETHOD_EPOLL) epoll_postfork_child (); #endif evio_stop (&sigev); close (sigpipe [0]); close (sigpipe [1]); pipe (sigpipe); siginit (); } /*****************************************************************************/ static void call_pending (void) { while (pendingcnt) { ANPENDING *p = pendings + --pendingcnt; if (p->w) { p->w->pending = 0; p->w->cb (p->w, p->events); } } } static void timers_reify (void) { while (timercnt && timers [0]->at <= now) { struct ev_timer *w = timers [0]; event ((W)w, EV_TIMEOUT); /* first reschedule or stop timer */ if (w->repeat) { w->at = now + w->repeat; assert (("timer timeout in the past, negative repeat?", w->at > now)); downheap ((WT *)timers, timercnt, 0); } else evtimer_stop (w); /* nonrepeating: stop timer */ } } static void periodics_reify (void) { while (periodiccnt && periodics [0]->at <= ev_now) { struct ev_periodic *w = periodics [0]; /* first reschedule or stop timer */ if (w->interval) { w->at += floor ((ev_now - w->at) / w->interval + 1.) * w->interval; assert (("periodic timeout in the past, negative interval?", w->at > ev_now)); downheap ((WT *)periodics, periodiccnt, 0); } else evperiodic_stop (w); /* nonrepeating: stop timer */ event ((W)w, EV_TIMEOUT); } } static void periodics_reschedule (ev_tstamp diff) { int i; /* adjust periodics after time jump */ for (i = 0; i < periodiccnt; ++i) { struct ev_periodic *w = periodics [i]; if (w->interval) { ev_tstamp diff = ceil ((ev_now - w->at) / w->interval) * w->interval; if (fabs (diff) >= 1e-4) { evperiodic_stop (w); evperiodic_start (w); i = 0; /* restart loop, inefficient, but time jumps should be rare */ } } } } static void time_update (void) { int i; ev_now = ev_time (); if (have_monotonic) { ev_tstamp odiff = diff; for (i = 4; --i; ) /* loop a few times, before making important decisions */ { now = get_clock (); diff = ev_now - now; if (fabs (odiff - diff) < MIN_TIMEJUMP) return; /* all is well */ ev_now = ev_time (); } periodics_reschedule (diff - odiff); /* no timer adjustment, as the monotonic clock doesn't jump */ } else { if (now > ev_now || now < ev_now - MAX_BLOCKTIME - MIN_TIMEJUMP) { periodics_reschedule (ev_now - now); /* adjust timers. this is easy, as the offset is the same for all */ for (i = 0; i < timercnt; ++i) timers [i]->at += diff; } now = ev_now; } } int ev_loop_done; void ev_loop (int flags) { double block; ev_loop_done = flags & (EVLOOP_ONESHOT | EVLOOP_NONBLOCK) ? 1 : 0; do { /* queue check watchers (and execute them) */ if (preparecnt) { queue_events ((W *)prepares, preparecnt, EV_PREPARE); call_pending (); } /* update fd-related kernel structures */ fd_reify (); /* calculate blocking time */ /* we only need this for !monotonic clockor timers, but as we basically always have timers, we just calculate it always */ ev_now = ev_time (); if (flags & EVLOOP_NONBLOCK || idlecnt) block = 0.; else { block = MAX_BLOCKTIME; if (timercnt) { ev_tstamp to = timers [0]->at - (have_monotonic ? get_clock () : ev_now) + method_fudge; if (block > to) block = to; } if (periodiccnt) { ev_tstamp to = periodics [0]->at - ev_now + method_fudge; if (block > to) block = to; } if (block < 0.) block = 0.; } method_poll (block); /* update ev_now, do magic */ time_update (); /* queue pending timers and reschedule them */ timers_reify (); /* relative timers called last */ periodics_reify (); /* absolute timers called first */ /* queue idle watchers unless io or timers are pending */ if (!pendingcnt) queue_events ((W *)idles, idlecnt, EV_IDLE); /* queue check watchers, to be executed first */ if (checkcnt) queue_events ((W *)checks, checkcnt, EV_CHECK); call_pending (); } while (!ev_loop_done); if (ev_loop_done != 2) ev_loop_done = 0; } /*****************************************************************************/ static void wlist_add (WL *head, WL elem) { elem->next = *head; *head = elem; } static void wlist_del (WL *head, WL elem) { while (*head) { if (*head == elem) { *head = elem->next; return; } head = &(*head)->next; } } static void ev_clear (W w) { if (w->pending) { pendings [w->pending - 1].w = 0; w->pending = 0; } } static void ev_start (W w, int active) { w->active = active; } static void ev_stop (W w) { w->active = 0; } /*****************************************************************************/ void evio_start (struct ev_io *w) { if (ev_is_active (w)) return; int fd = w->fd; ev_start ((W)w, 1); array_needsize (anfds, anfdmax, fd + 1, anfds_init); wlist_add ((WL *)&anfds[fd].head, (WL)w); fd_change (fd); } void evio_stop (struct ev_io *w) { ev_clear ((W)w); if (!ev_is_active (w)) return; wlist_del ((WL *)&anfds[w->fd].head, (WL)w); ev_stop ((W)w); fd_change (w->fd); } void evtimer_start (struct ev_timer *w) { if (ev_is_active (w)) return; w->at += now; assert (("timer repeat value less than zero not allowed", w->repeat >= 0.)); ev_start ((W)w, ++timercnt); array_needsize (timers, timermax, timercnt, ); timers [timercnt - 1] = w; upheap ((WT *)timers, timercnt - 1); } void evtimer_stop (struct ev_timer *w) { ev_clear ((W)w); if (!ev_is_active (w)) return; if (w->active < timercnt--) { timers [w->active - 1] = timers [timercnt]; downheap ((WT *)timers, timercnt, w->active - 1); } w->at = w->repeat; ev_stop ((W)w); } void evtimer_again (struct ev_timer *w) { if (ev_is_active (w)) { if (w->repeat) { w->at = now + w->repeat; downheap ((WT *)timers, timercnt, w->active - 1); } else evtimer_stop (w); } else if (w->repeat) evtimer_start (w); } void evperiodic_start (struct ev_periodic *w) { if (ev_is_active (w)) return; assert (("periodic interval value less than zero not allowed", w->interval >= 0.)); /* this formula differs from the one in periodic_reify because we do not always round up */ if (w->interval) w->at += ceil ((ev_now - w->at) / w->interval) * w->interval; ev_start ((W)w, ++periodiccnt); array_needsize (periodics, periodicmax, periodiccnt, ); periodics [periodiccnt - 1] = w; upheap ((WT *)periodics, periodiccnt - 1); } void evperiodic_stop (struct ev_periodic *w) { ev_clear ((W)w); if (!ev_is_active (w)) return; if (w->active < periodiccnt--) { periodics [w->active - 1] = periodics [periodiccnt]; downheap ((WT *)periodics, periodiccnt, w->active - 1); } ev_stop ((W)w); } void evsignal_start (struct ev_signal *w) { if (ev_is_active (w)) return; ev_start ((W)w, 1); array_needsize (signals, signalmax, w->signum, signals_init); wlist_add ((WL *)&signals [w->signum - 1].head, (WL)w); if (!w->next) { struct sigaction sa; sa.sa_handler = sighandler; sigfillset (&sa.sa_mask); sa.sa_flags = 0; sigaction (w->signum, &sa, 0); } } void evsignal_stop (struct ev_signal *w) { ev_clear ((W)w); if (!ev_is_active (w)) return; wlist_del ((WL *)&signals [w->signum - 1].head, (WL)w); ev_stop ((W)w); if (!signals [w->signum - 1].head) signal (w->signum, SIG_DFL); } void evidle_start (struct ev_idle *w) { if (ev_is_active (w)) return; ev_start ((W)w, ++idlecnt); array_needsize (idles, idlemax, idlecnt, ); idles [idlecnt - 1] = w; } void evidle_stop (struct ev_idle *w) { ev_clear ((W)w); if (ev_is_active (w)) return; idles [w->active - 1] = idles [--idlecnt]; ev_stop ((W)w); } void evprepare_start (struct ev_prepare *w) { if (ev_is_active (w)) return; ev_start ((W)w, ++preparecnt); array_needsize (prepares, preparemax, preparecnt, ); prepares [preparecnt - 1] = w; } void evprepare_stop (struct ev_prepare *w) { ev_clear ((W)w); if (ev_is_active (w)) return; prepares [w->active - 1] = prepares [--preparecnt]; ev_stop ((W)w); } void evcheck_start (struct ev_check *w) { if (ev_is_active (w)) return; ev_start ((W)w, ++checkcnt); array_needsize (checks, checkmax, checkcnt, ); checks [checkcnt - 1] = w; } void evcheck_stop (struct ev_check *w) { ev_clear ((W)w); if (ev_is_active (w)) return; checks [w->active - 1] = checks [--checkcnt]; ev_stop ((W)w); } void evchild_start (struct ev_child *w) { if (ev_is_active (w)) return; ev_start ((W)w, 1); wlist_add ((WL *)&childs [w->pid & (PID_HASHSIZE - 1)], (WL)w); } void evchild_stop (struct ev_child *w) { ev_clear ((W)w); if (ev_is_active (w)) return; wlist_del ((WL *)&childs [w->pid & (PID_HASHSIZE - 1)], (WL)w); ev_stop ((W)w); } /*****************************************************************************/ struct ev_once { struct ev_io io; struct ev_timer to; void (*cb)(int revents, void *arg); void *arg; }; static void once_cb (struct ev_once *once, int revents) { void (*cb)(int revents, void *arg) = once->cb; void *arg = once->arg; evio_stop (&once->io); evtimer_stop (&once->to); free (once); cb (revents, arg); } static void once_cb_io (struct ev_io *w, int revents) { once_cb ((struct ev_once *)(((char *)w) - offsetof (struct ev_once, io)), revents); } static void once_cb_to (struct ev_timer *w, int revents) { once_cb ((struct ev_once *)(((char *)w) - offsetof (struct ev_once, to)), revents); } void ev_once (int fd, int events, ev_tstamp timeout, void (*cb)(int revents, void *arg), void *arg) { struct ev_once *once = malloc (sizeof (struct ev_once)); if (!once) cb (EV_ERROR, arg); else { once->cb = cb; once->arg = arg; evw_init (&once->io, once_cb_io); if (fd >= 0) { evio_set (&once->io, fd, events); evio_start (&once->io); } evw_init (&once->to, once_cb_to); if (timeout >= 0.) { evtimer_set (&once->to, timeout, 0.); evtimer_start (&once->to); } } } /*****************************************************************************/ #if 0 struct ev_io wio; static void sin_cb (struct ev_io *w, int revents) { fprintf (stderr, "sin %d, revents %d\n", w->fd, revents); } static void ocb (struct ev_timer *w, int revents) { //fprintf (stderr, "timer %f,%f (%x) (%f) d%p\n", w->at, w->repeat, revents, w->at - ev_time (), w->data); evtimer_stop (w); evtimer_start (w); } static void scb (struct ev_signal *w, int revents) { fprintf (stderr, "signal %x,%d\n", revents, w->signum); evio_stop (&wio); evio_start (&wio); } static void gcb (struct ev_signal *w, int revents) { fprintf (stderr, "generic %x\n", revents); } int main (void) { ev_init (0); evio_init (&wio, sin_cb, 0, EV_READ); evio_start (&wio); struct ev_timer t[10000]; #if 0 int i; for (i = 0; i < 10000; ++i) { struct ev_timer *w = t + i; evw_init (w, ocb, i); evtimer_init_abs (w, ocb, drand48 (), 0.99775533); evtimer_start (w); if (drand48 () < 0.5) evtimer_stop (w); } #endif struct ev_timer t1; evtimer_init (&t1, ocb, 5, 10); evtimer_start (&t1); struct ev_signal sig; evsignal_init (&sig, scb, SIGQUIT); evsignal_start (&sig); struct ev_check cw; evcheck_init (&cw, gcb); evcheck_start (&cw); struct ev_idle iw; evidle_init (&iw, gcb); evidle_start (&iw); ev_loop (0); return 0; } #endif