From 36d22d82aa202bb199967e9512281e9a53db42c9 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 21:33:14 +0200 Subject: Adding upstream version 115.7.0esr. Signed-off-by: Daniel Baumann --- ipc/chromium/src/third_party/libevent/evport.c | 451 +++++++++++++++++++++++++ 1 file changed, 451 insertions(+) create mode 100644 ipc/chromium/src/third_party/libevent/evport.c (limited to 'ipc/chromium/src/third_party/libevent/evport.c') diff --git a/ipc/chromium/src/third_party/libevent/evport.c b/ipc/chromium/src/third_party/libevent/evport.c new file mode 100644 index 0000000000..a014386bfe --- /dev/null +++ b/ipc/chromium/src/third_party/libevent/evport.c @@ -0,0 +1,451 @@ +/* + * Submitted by David Pacheco (dp.spambait@gmail.com) + * + * Copyright 2006-2007 Niels Provos + * Copyright 2007-2012 Niels Provos and Nick Mathewson + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. 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. + * 3. The name of the author may not be used to endorse or promote products + * derived from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY SUN MICROSYSTEMS, INC. ``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 SUN MICROSYSTEMS, INC. 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. + */ + +/* + * Copyright (c) 2007 Sun Microsystems. All rights reserved. + * Use is subject to license terms. + */ + +/* + * evport.c: event backend using Solaris 10 event ports. See port_create(3C). + * This implementation is loosely modeled after the one used for select(2) (in + * select.c). + * + * The outstanding events are tracked in a data structure called evport_data. + * Each entry in the ed_fds array corresponds to a file descriptor, and contains + * pointers to the read and write events that correspond to that fd. (That is, + * when the file is readable, the "read" event should handle it, etc.) + * + * evport_add and evport_del update this data structure. evport_dispatch uses it + * to determine where to callback when an event occurs (which it gets from + * port_getn). + * + * Helper functions are used: grow() grows the file descriptor array as + * necessary when large fd's come in. reassociate() takes care of maintaining + * the proper file-descriptor/event-port associations. + * + * As in the select(2) implementation, signals are handled by evsignal. + */ + +#include "event2/event-config.h" +#include "evconfig-private.h" + +#ifdef EVENT__HAVE_EVENT_PORTS + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "event2/thread.h" + +#include "evthread-internal.h" +#include "event-internal.h" +#include "log-internal.h" +#include "evsignal-internal.h" +#include "evmap-internal.h" + +#define INITIAL_EVENTS_PER_GETN 8 +#define MAX_EVENTS_PER_GETN 4096 + +/* + * Per-file-descriptor information about what events we're subscribed to. These + * fields are NULL if no event is subscribed to either of them. + */ + +struct fd_info { + /* combinations of EV_READ and EV_WRITE */ + short fdi_what; + /* Index of this fd within ed_pending, plus 1. Zero if this fd is + * not in ed_pending. (The +1 is a hack so that memset(0) will set + * it to a nil index. */ + int pending_idx_plus_1; +}; + +#define FDI_HAS_READ(fdi) ((fdi)->fdi_what & EV_READ) +#define FDI_HAS_WRITE(fdi) ((fdi)->fdi_what & EV_WRITE) +#define FDI_HAS_EVENTS(fdi) (FDI_HAS_READ(fdi) || FDI_HAS_WRITE(fdi)) +#define FDI_TO_SYSEVENTS(fdi) (FDI_HAS_READ(fdi) ? POLLIN : 0) | \ + (FDI_HAS_WRITE(fdi) ? POLLOUT : 0) + +struct evport_data { + int ed_port; /* event port for system events */ + /* How many elements of ed_pending should we look at? */ + int ed_npending; + /* How many elements are allocated in ed_pending and pevtlist? */ + int ed_maxevents; + /* fdi's that we need to reassoc */ + int *ed_pending; + /* storage space for incoming events. */ + port_event_t *ed_pevtlist; + +}; + +static void* evport_init(struct event_base *); +static int evport_add(struct event_base *, int fd, short old, short events, void *); +static int evport_del(struct event_base *, int fd, short old, short events, void *); +static int evport_dispatch(struct event_base *, struct timeval *); +static void evport_dealloc(struct event_base *); +static int grow(struct evport_data *, int min_events); + +const struct eventop evportops = { + "evport", + evport_init, + evport_add, + evport_del, + evport_dispatch, + evport_dealloc, + 1, /* need reinit */ + 0, /* features */ + sizeof(struct fd_info), /* fdinfo length */ +}; + +/* + * Initialize the event port implementation. + */ + +static void* +evport_init(struct event_base *base) +{ + struct evport_data *evpd; + + if (!(evpd = mm_calloc(1, sizeof(struct evport_data)))) + return (NULL); + + if ((evpd->ed_port = port_create()) == -1) { + mm_free(evpd); + return (NULL); + } + + if (grow(evpd, INITIAL_EVENTS_PER_GETN) < 0) { + close(evpd->ed_port); + mm_free(evpd); + return NULL; + } + + evpd->ed_npending = 0; + + evsig_init_(base); + + return (evpd); +} + +static int +grow(struct evport_data *data, int min_events) +{ + int newsize; + int *new_pending; + port_event_t *new_pevtlist; + if (data->ed_maxevents) { + newsize = data->ed_maxevents; + do { + newsize *= 2; + } while (newsize < min_events); + } else { + newsize = min_events; + } + + new_pending = mm_realloc(data->ed_pending, sizeof(int)*newsize); + if (new_pending == NULL) + return -1; + data->ed_pending = new_pending; + new_pevtlist = mm_realloc(data->ed_pevtlist, sizeof(port_event_t)*newsize); + if (new_pevtlist == NULL) + return -1; + data->ed_pevtlist = new_pevtlist; + + data->ed_maxevents = newsize; + return 0; +} + +#ifdef CHECK_INVARIANTS +/* + * Checks some basic properties about the evport_data structure. Because it + * checks all file descriptors, this function can be expensive when the maximum + * file descriptor ever used is rather large. + */ + +static void +check_evportop(struct evport_data *evpd) +{ + EVUTIL_ASSERT(evpd); + EVUTIL_ASSERT(evpd->ed_port > 0); +} + +/* + * Verifies very basic integrity of a given port_event. + */ +static void +check_event(port_event_t* pevt) +{ + /* + * We've only registered for PORT_SOURCE_FD events. The only + * other thing we can legitimately receive is PORT_SOURCE_ALERT, + * but since we're not using port_alert either, we can assume + * PORT_SOURCE_FD. + */ + EVUTIL_ASSERT(pevt->portev_source == PORT_SOURCE_FD); +} + +#else +#define check_evportop(epop) +#define check_event(pevt) +#endif /* CHECK_INVARIANTS */ + +/* + * (Re)associates the given file descriptor with the event port. The OS events + * are specified (implicitly) from the fd_info struct. + */ +static int +reassociate(struct evport_data *epdp, struct fd_info *fdip, int fd) +{ + int sysevents = FDI_TO_SYSEVENTS(fdip); + + if (sysevents != 0) { + if (port_associate(epdp->ed_port, PORT_SOURCE_FD, + fd, sysevents, fdip) == -1) { + event_warn("port_associate"); + return (-1); + } + } + + check_evportop(epdp); + + return (0); +} + +/* + * Main event loop - polls port_getn for some number of events, and processes + * them. + */ + +static int +evport_dispatch(struct event_base *base, struct timeval *tv) +{ + int i, res; + struct evport_data *epdp = base->evbase; + port_event_t *pevtlist = epdp->ed_pevtlist; + + /* + * port_getn will block until it has at least nevents events. It will + * also return how many it's given us (which may be more than we asked + * for, as long as it's less than our maximum (ed_maxevents)) in + * nevents. + */ + int nevents = 1; + + /* + * We have to convert a struct timeval to a struct timespec + * (only difference is nanoseconds vs. microseconds). If no time-based + * events are active, we should wait for I/O (and tv == NULL). + */ + struct timespec ts; + struct timespec *ts_p = NULL; + if (tv != NULL) { + ts.tv_sec = tv->tv_sec; + ts.tv_nsec = tv->tv_usec * 1000; + ts_p = &ts; + } + + /* + * Before doing anything else, we need to reassociate the events we hit + * last time which need reassociation. See comment at the end of the + * loop below. + */ + for (i = 0; i < epdp->ed_npending; ++i) { + struct fd_info *fdi = NULL; + const int fd = epdp->ed_pending[i]; + if (fd != -1) { + /* We might have cleared out this event; we need + * to be sure that it's still set. */ + fdi = evmap_io_get_fdinfo_(&base->io, fd); + } + + if (fdi != NULL && FDI_HAS_EVENTS(fdi)) { + reassociate(epdp, fdi, fd); + /* epdp->ed_pending[i] = -1; */ + fdi->pending_idx_plus_1 = 0; + } + } + + EVBASE_RELEASE_LOCK(base, th_base_lock); + + res = port_getn(epdp->ed_port, pevtlist, epdp->ed_maxevents, + (unsigned int *) &nevents, ts_p); + + EVBASE_ACQUIRE_LOCK(base, th_base_lock); + + if (res == -1) { + if (errno == EINTR || errno == EAGAIN) { + return (0); + } else if (errno == ETIME) { + if (nevents == 0) + return (0); + } else { + event_warn("port_getn"); + return (-1); + } + } + + event_debug(("%s: port_getn reports %d events", __func__, nevents)); + + for (i = 0; i < nevents; ++i) { + port_event_t *pevt = &pevtlist[i]; + int fd = (int) pevt->portev_object; + struct fd_info *fdi = pevt->portev_user; + /*EVUTIL_ASSERT(evmap_io_get_fdinfo_(&base->io, fd) == fdi);*/ + + check_evportop(epdp); + check_event(pevt); + epdp->ed_pending[i] = fd; + fdi->pending_idx_plus_1 = i + 1; + + /* + * Figure out what kind of event it was + * (because we have to pass this to the callback) + */ + res = 0; + if (pevt->portev_events & (POLLERR|POLLHUP)) { + res = EV_READ | EV_WRITE; + } else { + if (pevt->portev_events & POLLIN) + res |= EV_READ; + if (pevt->portev_events & POLLOUT) + res |= EV_WRITE; + } + + /* + * Check for the error situations or a hangup situation + */ + if (pevt->portev_events & (POLLERR|POLLHUP|POLLNVAL)) + res |= EV_READ|EV_WRITE; + + evmap_io_active_(base, fd, res); + } /* end of all events gotten */ + epdp->ed_npending = nevents; + + if (nevents == epdp->ed_maxevents && + epdp->ed_maxevents < MAX_EVENTS_PER_GETN) { + /* we used all the space this time. We should be ready + * for more events next time around. */ + grow(epdp, epdp->ed_maxevents * 2); + } + + check_evportop(epdp); + + return (0); +} + + +/* + * Adds the given event (so that you will be notified when it happens via + * the callback function). + */ + +static int +evport_add(struct event_base *base, int fd, short old, short events, void *p) +{ + struct evport_data *evpd = base->evbase; + struct fd_info *fdi = p; + + check_evportop(evpd); + + fdi->fdi_what |= events; + + return reassociate(evpd, fdi, fd); +} + +/* + * Removes the given event from the list of events to wait for. + */ + +static int +evport_del(struct event_base *base, int fd, short old, short events, void *p) +{ + struct evport_data *evpd = base->evbase; + struct fd_info *fdi = p; + int associated = ! fdi->pending_idx_plus_1; + + check_evportop(evpd); + + fdi->fdi_what &= ~(events &(EV_READ|EV_WRITE)); + + if (associated) { + if (!FDI_HAS_EVENTS(fdi) && + port_dissociate(evpd->ed_port, PORT_SOURCE_FD, fd) == -1) { + /* + * Ignore EBADFD error the fd could have been closed + * before event_del() was called. + */ + if (errno != EBADFD) { + event_warn("port_dissociate"); + return (-1); + } + } else { + if (FDI_HAS_EVENTS(fdi)) { + return (reassociate(evpd, fdi, fd)); + } + } + } else { + if ((fdi->fdi_what & (EV_READ|EV_WRITE)) == 0) { + const int i = fdi->pending_idx_plus_1 - 1; + EVUTIL_ASSERT(evpd->ed_pending[i] == fd); + evpd->ed_pending[i] = -1; + fdi->pending_idx_plus_1 = 0; + } + } + return 0; +} + + +static void +evport_dealloc(struct event_base *base) +{ + struct evport_data *evpd = base->evbase; + + evsig_dealloc_(base); + + close(evpd->ed_port); + + if (evpd->ed_pending) + mm_free(evpd->ed_pending); + if (evpd->ed_pevtlist) + mm_free(evpd->ed_pevtlist); + + mm_free(evpd); +} + +#endif /* EVENT__HAVE_EVENT_PORTS */ -- cgit v1.2.3