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Diffstat (limited to 'libs/libevent/src/evmap.c')
| -rw-r--r-- | libs/libevent/src/evmap.c | 1055 |
1 files changed, 1055 insertions, 0 deletions
diff --git a/libs/libevent/src/evmap.c b/libs/libevent/src/evmap.c new file mode 100644 index 0000000000..3f76dd0ae1 --- /dev/null +++ b/libs/libevent/src/evmap.c @@ -0,0 +1,1055 @@ +/* + * Copyright (c) 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 THE AUTHOR ``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 AUTHOR 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 "event2/event-config.h" +#include "evconfig-private.h" + +#ifdef _WIN32 +#include <winsock2.h> +#define WIN32_LEAN_AND_MEAN +#include <windows.h> +#undef WIN32_LEAN_AND_MEAN +#endif +#include <sys/types.h> +#if !defined(_WIN32) && defined(EVENT__HAVE_SYS_TIME_H) +#include <sys/time.h> +#endif +#include <sys/queue.h> +#include <stdio.h> +#include <stdlib.h> +#ifndef _WIN32 +#include <unistd.h> +#endif +#include <errno.h> +#include <signal.h> +#include <string.h> +#include <time.h> + +#include "event-internal.h" +#include "evmap-internal.h" +#include "mm-internal.h" +#include "changelist-internal.h" + +/** An entry for an evmap_io list: notes all the events that want to read or + write on a given fd, and the number of each. + */ +struct evmap_io { + struct event_dlist events; + ev_uint16_t nread; + ev_uint16_t nwrite; + ev_uint16_t nclose; +}; + +/* An entry for an evmap_signal list: notes all the events that want to know + when a signal triggers. */ +struct evmap_signal { + struct event_dlist events; +}; + +/* On some platforms, fds start at 0 and increment by 1 as they are + allocated, and old numbers get used. For these platforms, we + implement io maps just like signal maps: as an array of pointers to + struct evmap_io. But on other platforms (windows), sockets are not + 0-indexed, not necessarily consecutive, and not necessarily reused. + There, we use a hashtable to implement evmap_io. +*/ +#ifdef EVMAP_USE_HT +struct event_map_entry { + HT_ENTRY(event_map_entry) map_node; + evutil_socket_t fd; + union { /* This is a union in case we need to make more things that can + be in the hashtable. */ + struct evmap_io evmap_io; + } ent; +}; + +/* Helper used by the event_io_map hashtable code; tries to return a good hash + * of the fd in e->fd. */ +static inline unsigned +hashsocket(struct event_map_entry *e) +{ + /* On win32, in practice, the low 2-3 bits of a SOCKET seem not to + * matter. Our hashtable implementation really likes low-order bits, + * though, so let's do the rotate-and-add trick. */ + unsigned h = (unsigned) e->fd; + h += (h >> 2) | (h << 30); + return h; +} + +/* Helper used by the event_io_map hashtable code; returns true iff e1 and e2 + * have the same e->fd. */ +static inline int +eqsocket(struct event_map_entry *e1, struct event_map_entry *e2) +{ + return e1->fd == e2->fd; +} + +HT_PROTOTYPE(event_io_map, event_map_entry, map_node, hashsocket, eqsocket) +HT_GENERATE(event_io_map, event_map_entry, map_node, hashsocket, eqsocket, + 0.5, mm_malloc, mm_realloc, mm_free) + +#define GET_IO_SLOT(x, map, slot, type) \ + do { \ + struct event_map_entry key_, *ent_; \ + key_.fd = slot; \ + ent_ = HT_FIND(event_io_map, map, &key_); \ + (x) = ent_ ? &ent_->ent.type : NULL; \ + } while (0); + +#define GET_IO_SLOT_AND_CTOR(x, map, slot, type, ctor, fdinfo_len) \ + do { \ + struct event_map_entry key_, *ent_; \ + key_.fd = slot; \ + HT_FIND_OR_INSERT_(event_io_map, map_node, hashsocket, map, \ + event_map_entry, &key_, ptr, \ + { \ + ent_ = *ptr; \ + }, \ + { \ + ent_ = mm_calloc(1,sizeof(struct event_map_entry)+fdinfo_len); \ + if (EVUTIL_UNLIKELY(ent_ == NULL)) \ + return (-1); \ + ent_->fd = slot; \ + (ctor)(&ent_->ent.type); \ + HT_FOI_INSERT_(map_node, map, &key_, ent_, ptr) \ + }); \ + (x) = &ent_->ent.type; \ + } while (0) + +void evmap_io_initmap_(struct event_io_map *ctx) +{ + HT_INIT(event_io_map, ctx); +} + +void evmap_io_clear_(struct event_io_map *ctx) +{ + struct event_map_entry **ent, **next, *this; + for (ent = HT_START(event_io_map, ctx); ent; ent = next) { + this = *ent; + next = HT_NEXT_RMV(event_io_map, ctx, ent); + mm_free(this); + } + HT_CLEAR(event_io_map, ctx); /* remove all storage held by the ctx. */ +} +#endif + +/* Set the variable 'x' to the field in event_map 'map' with fields of type + 'struct type *' corresponding to the fd or signal 'slot'. Set 'x' to NULL + if there are no entries for 'slot'. Does no bounds-checking. */ +#define GET_SIGNAL_SLOT(x, map, slot, type) \ + (x) = (struct type *)((map)->entries[slot]) +/* As GET_SLOT, but construct the entry for 'slot' if it is not present, + by allocating enough memory for a 'struct type', and initializing the new + value by calling the function 'ctor' on it. Makes the function + return -1 on allocation failure. + */ +#define GET_SIGNAL_SLOT_AND_CTOR(x, map, slot, type, ctor, fdinfo_len) \ + do { \ + if ((map)->entries[slot] == NULL) { \ + (map)->entries[slot] = \ + mm_calloc(1,sizeof(struct type)+fdinfo_len); \ + if (EVUTIL_UNLIKELY((map)->entries[slot] == NULL)) \ + return (-1); \ + (ctor)((struct type *)(map)->entries[slot]); \ + } \ + (x) = (struct type *)((map)->entries[slot]); \ + } while (0) + +/* If we aren't using hashtables, then define the IO_SLOT macros and functions + as thin aliases over the SIGNAL_SLOT versions. */ +#ifndef EVMAP_USE_HT +#define GET_IO_SLOT(x,map,slot,type) GET_SIGNAL_SLOT(x,map,slot,type) +#define GET_IO_SLOT_AND_CTOR(x,map,slot,type,ctor,fdinfo_len) \ + GET_SIGNAL_SLOT_AND_CTOR(x,map,slot,type,ctor,fdinfo_len) +#define FDINFO_OFFSET sizeof(struct evmap_io) +void +evmap_io_initmap_(struct event_io_map* ctx) +{ + evmap_signal_initmap_(ctx); +} +void +evmap_io_clear_(struct event_io_map* ctx) +{ + evmap_signal_clear_(ctx); +} +#endif + + +/** Expand 'map' with new entries of width 'msize' until it is big enough + to store a value in 'slot'. + */ +static int +evmap_make_space(struct event_signal_map *map, int slot, int msize) +{ + if (map->nentries <= slot) { + int nentries = map->nentries ? map->nentries : 32; + void **tmp; + + while (nentries <= slot) + nentries <<= 1; + + tmp = (void **)mm_realloc(map->entries, nentries * msize); + if (tmp == NULL) + return (-1); + + memset(&tmp[map->nentries], 0, + (nentries - map->nentries) * msize); + + map->nentries = nentries; + map->entries = tmp; + } + + return (0); +} + +void +evmap_signal_initmap_(struct event_signal_map *ctx) +{ + ctx->nentries = 0; + ctx->entries = NULL; +} + +void +evmap_signal_clear_(struct event_signal_map *ctx) +{ + if (ctx->entries != NULL) { + int i; + for (i = 0; i < ctx->nentries; ++i) { + if (ctx->entries[i] != NULL) + mm_free(ctx->entries[i]); + } + mm_free(ctx->entries); + ctx->entries = NULL; + } + ctx->nentries = 0; +} + + +/* code specific to file descriptors */ + +/** Constructor for struct evmap_io */ +static void +evmap_io_init(struct evmap_io *entry) +{ + LIST_INIT(&entry->events); + entry->nread = 0; + entry->nwrite = 0; + entry->nclose = 0; +} + + +/* return -1 on error, 0 on success if nothing changed in the event backend, + * and 1 on success if something did. */ +int +evmap_io_add_(struct event_base *base, evutil_socket_t fd, struct event *ev) +{ + const struct eventop *evsel = base->evsel; + struct event_io_map *io = &base->io; + struct evmap_io *ctx = NULL; + int nread, nwrite, nclose, retval = 0; + short res = 0, old = 0; + struct event *old_ev; + + EVUTIL_ASSERT(fd == ev->ev_fd); + + if (fd < 0) + return 0; + +#ifndef EVMAP_USE_HT + if (fd >= io->nentries) { + if (evmap_make_space(io, fd, sizeof(struct evmap_io *)) == -1) + return (-1); + } +#endif + GET_IO_SLOT_AND_CTOR(ctx, io, fd, evmap_io, evmap_io_init, + evsel->fdinfo_len); + + nread = ctx->nread; + nwrite = ctx->nwrite; + nclose = ctx->nclose; + + if (nread) + old |= EV_READ; + if (nwrite) + old |= EV_WRITE; + if (nclose) + old |= EV_CLOSED; + + if (ev->ev_events & EV_READ) { + if (++nread == 1) + res |= EV_READ; + } + if (ev->ev_events & EV_WRITE) { + if (++nwrite == 1) + res |= EV_WRITE; + } + if (ev->ev_events & EV_CLOSED) { + if (++nclose == 1) + res |= EV_CLOSED; + } + if (EVUTIL_UNLIKELY(nread > 0xffff || nwrite > 0xffff || nclose > 0xffff)) { + event_warnx("Too many events reading or writing on fd %d", + (int)fd); + return -1; + } + if (EVENT_DEBUG_MODE_IS_ON() && + (old_ev = LIST_FIRST(&ctx->events)) && + (old_ev->ev_events&EV_ET) != (ev->ev_events&EV_ET)) { + event_warnx("Tried to mix edge-triggered and non-edge-triggered" + " events on fd %d", (int)fd); + return -1; + } + + if (res) { + void *extra = ((char*)ctx) + sizeof(struct evmap_io); + /* XXX(niels): we cannot mix edge-triggered and + * level-triggered, we should probably assert on + * this. */ + if (evsel->add(base, ev->ev_fd, + old, (ev->ev_events & EV_ET) | res, extra) == -1) + return (-1); + retval = 1; + } + + ctx->nread = (ev_uint16_t) nread; + ctx->nwrite = (ev_uint16_t) nwrite; + ctx->nclose = (ev_uint16_t) nclose; + LIST_INSERT_HEAD(&ctx->events, ev, ev_io_next); + + return (retval); +} + +/* return -1 on error, 0 on success if nothing changed in the event backend, + * and 1 on success if something did. */ +int +evmap_io_del_(struct event_base *base, evutil_socket_t fd, struct event *ev) +{ + const struct eventop *evsel = base->evsel; + struct event_io_map *io = &base->io; + struct evmap_io *ctx; + int nread, nwrite, nclose, retval = 0; + short res = 0, old = 0; + + if (fd < 0) + return 0; + + EVUTIL_ASSERT(fd == ev->ev_fd); + +#ifndef EVMAP_USE_HT + if (fd >= io->nentries) + return (-1); +#endif + + GET_IO_SLOT(ctx, io, fd, evmap_io); + + nread = ctx->nread; + nwrite = ctx->nwrite; + nclose = ctx->nclose; + + if (nread) + old |= EV_READ; + if (nwrite) + old |= EV_WRITE; + if (nclose) + old |= EV_CLOSED; + + if (ev->ev_events & EV_READ) { + if (--nread == 0) + res |= EV_READ; + EVUTIL_ASSERT(nread >= 0); + } + if (ev->ev_events & EV_WRITE) { + if (--nwrite == 0) + res |= EV_WRITE; + EVUTIL_ASSERT(nwrite >= 0); + } + if (ev->ev_events & EV_CLOSED) { + if (--nclose == 0) + res |= EV_CLOSED; + EVUTIL_ASSERT(nclose >= 0); + } + + if (res) { + void *extra = ((char*)ctx) + sizeof(struct evmap_io); + if (evsel->del(base, ev->ev_fd, old, res, extra) == -1) { + retval = -1; + } else { + retval = 1; + } + } + + ctx->nread = nread; + ctx->nwrite = nwrite; + ctx->nclose = nclose; + LIST_REMOVE(ev, ev_io_next); + + return (retval); +} + +void +evmap_io_active_(struct event_base *base, evutil_socket_t fd, short events) +{ + struct event_io_map *io = &base->io; + struct evmap_io *ctx; + struct event *ev; + +#ifndef EVMAP_USE_HT + if (fd < 0 || fd >= io->nentries) + return; +#endif + GET_IO_SLOT(ctx, io, fd, evmap_io); + + if (NULL == ctx) + return; + LIST_FOREACH(ev, &ctx->events, ev_io_next) { + if (ev->ev_events & events) + event_active_nolock_(ev, ev->ev_events & events, 1); + } +} + +/* code specific to signals */ + +static void +evmap_signal_init(struct evmap_signal *entry) +{ + LIST_INIT(&entry->events); +} + + +int +evmap_signal_add_(struct event_base *base, int sig, struct event *ev) +{ + const struct eventop *evsel = base->evsigsel; + struct event_signal_map *map = &base->sigmap; + struct evmap_signal *ctx = NULL; + + if (sig >= map->nentries) { + if (evmap_make_space( + map, sig, sizeof(struct evmap_signal *)) == -1) + return (-1); + } + GET_SIGNAL_SLOT_AND_CTOR(ctx, map, sig, evmap_signal, evmap_signal_init, + base->evsigsel->fdinfo_len); + + if (LIST_EMPTY(&ctx->events)) { + if (evsel->add(base, ev->ev_fd, 0, EV_SIGNAL, NULL) + == -1) + return (-1); + } + + LIST_INSERT_HEAD(&ctx->events, ev, ev_signal_next); + + return (1); +} + +int +evmap_signal_del_(struct event_base *base, int sig, struct event *ev) +{ + const struct eventop *evsel = base->evsigsel; + struct event_signal_map *map = &base->sigmap; + struct evmap_signal *ctx; + + if (sig >= map->nentries) + return (-1); + + GET_SIGNAL_SLOT(ctx, map, sig, evmap_signal); + + LIST_REMOVE(ev, ev_signal_next); + + if (LIST_FIRST(&ctx->events) == NULL) { + if (evsel->del(base, ev->ev_fd, 0, EV_SIGNAL, NULL) == -1) + return (-1); + } + + return (1); +} + +void +evmap_signal_active_(struct event_base *base, evutil_socket_t sig, int ncalls) +{ + struct event_signal_map *map = &base->sigmap; + struct evmap_signal *ctx; + struct event *ev; + + if (sig < 0 || sig >= map->nentries) + return; + GET_SIGNAL_SLOT(ctx, map, sig, evmap_signal); + + if (!ctx) + return; + LIST_FOREACH(ev, &ctx->events, ev_signal_next) + event_active_nolock_(ev, EV_SIGNAL, ncalls); +} + +void * +evmap_io_get_fdinfo_(struct event_io_map *map, evutil_socket_t fd) +{ + struct evmap_io *ctx; + GET_IO_SLOT(ctx, map, fd, evmap_io); + if (ctx) + return ((char*)ctx) + sizeof(struct evmap_io); + else + return NULL; +} + +/* Callback type for evmap_io_foreach_fd */ +typedef int (*evmap_io_foreach_fd_cb)( + struct event_base *, evutil_socket_t, struct evmap_io *, void *); + +/* Multipurpose helper function: Iterate over every file descriptor event_base + * for which we could have EV_READ or EV_WRITE events. For each such fd, call + * fn(base, signum, evmap_io, arg), where fn is the user-provided + * function, base is the event_base, signum is the signal number, evmap_io + * is an evmap_io structure containing a list of events pending on the + * file descriptor, and arg is the user-supplied argument. + * + * If fn returns 0, continue on to the next signal. Otherwise, return the same + * value that fn returned. + * + * Note that there is no guarantee that the file descriptors will be processed + * in any particular order. + */ +static int +evmap_io_foreach_fd(struct event_base *base, + evmap_io_foreach_fd_cb fn, + void *arg) +{ + evutil_socket_t fd; + struct event_io_map *iomap = &base->io; + int r = 0; +#ifdef EVMAP_USE_HT + struct event_map_entry **mapent; + HT_FOREACH(mapent, event_io_map, iomap) { + struct evmap_io *ctx = &(*mapent)->ent.evmap_io; + fd = (*mapent)->fd; +#else + for (fd = 0; fd < iomap->nentries; ++fd) { + struct evmap_io *ctx = iomap->entries[fd]; + if (!ctx) + continue; +#endif + if ((r = fn(base, fd, ctx, arg))) + break; + } + return r; +} + +/* Callback type for evmap_signal_foreach_signal */ +typedef int (*evmap_signal_foreach_signal_cb)( + struct event_base *, int, struct evmap_signal *, void *); + +/* Multipurpose helper function: Iterate over every signal number in the + * event_base for which we could have signal events. For each such signal, + * call fn(base, signum, evmap_signal, arg), where fn is the user-provided + * function, base is the event_base, signum is the signal number, evmap_signal + * is an evmap_signal structure containing a list of events pending on the + * signal, and arg is the user-supplied argument. + * + * If fn returns 0, continue on to the next signal. Otherwise, return the same + * value that fn returned. + */ +static int +evmap_signal_foreach_signal(struct event_base *base, + evmap_signal_foreach_signal_cb fn, + void *arg) +{ + struct event_signal_map *sigmap = &base->sigmap; + int r = 0; + int signum; + + for (signum = 0; signum < sigmap->nentries; ++signum) { + struct evmap_signal *ctx = sigmap->entries[signum]; + if (!ctx) + continue; + if ((r = fn(base, signum, ctx, arg))) + break; + } + return r; +} + +/* Helper for evmap_reinit_: tell the backend to add every fd for which we have + * pending events, with the appropriate combination of EV_READ, EV_WRITE, and + * EV_ET. */ +static int +evmap_io_reinit_iter_fn(struct event_base *base, evutil_socket_t fd, + struct evmap_io *ctx, void *arg) +{ + const struct eventop *evsel = base->evsel; + void *extra; + int *result = arg; + short events = 0; + struct event *ev; + EVUTIL_ASSERT(ctx); + + extra = ((char*)ctx) + sizeof(struct evmap_io); + if (ctx->nread) + events |= EV_READ; + if (ctx->nwrite) + events |= EV_WRITE; + if (ctx->nclose) + events |= EV_CLOSED; + if (evsel->fdinfo_len) + memset(extra, 0, evsel->fdinfo_len); + if (events && + (ev = LIST_FIRST(&ctx->events)) && + (ev->ev_events & EV_ET)) + events |= EV_ET; + if (evsel->add(base, fd, 0, events, extra) == -1) + *result = -1; + + return 0; +} + +/* Helper for evmap_reinit_: tell the backend to add every signal for which we + * have pending events. */ +static int +evmap_signal_reinit_iter_fn(struct event_base *base, + int signum, struct evmap_signal *ctx, void *arg) +{ + const struct eventop *evsel = base->evsigsel; + int *result = arg; + + if (!LIST_EMPTY(&ctx->events)) { + if (evsel->add(base, signum, 0, EV_SIGNAL, NULL) == -1) + *result = -1; + } + return 0; +} + +int +evmap_reinit_(struct event_base *base) +{ + int result = 0; + + evmap_io_foreach_fd(base, evmap_io_reinit_iter_fn, &result); + if (result < 0) + return -1; + evmap_signal_foreach_signal(base, evmap_signal_reinit_iter_fn, &result); + if (result < 0) + return -1; + return 0; +} + +/* Helper for evmap_delete_all_: delete every event in an event_dlist. */ +static int +delete_all_in_dlist(struct event_dlist *dlist) +{ + struct event *ev; + while ((ev = LIST_FIRST(dlist))) + event_del(ev); + return 0; +} + +/* Helper for evmap_delete_all_: delete every event pending on an fd. */ +static int +evmap_io_delete_all_iter_fn(struct event_base *base, evutil_socket_t fd, + struct evmap_io *io_info, void *arg) +{ + return delete_all_in_dlist(&io_info->events); +} + +/* Helper for evmap_delete_all_: delete every event pending on a signal. */ +static int +evmap_signal_delete_all_iter_fn(struct event_base *base, int signum, + struct evmap_signal *sig_info, void *arg) +{ + return delete_all_in_dlist(&sig_info->events); +} + +void +evmap_delete_all_(struct event_base *base) +{ + evmap_signal_foreach_signal(base, evmap_signal_delete_all_iter_fn, NULL); + evmap_io_foreach_fd(base, evmap_io_delete_all_iter_fn, NULL); +} + +/** Per-fd structure for use with changelists. It keeps track, for each fd or + * signal using the changelist, of where its entry in the changelist is. + */ +struct event_changelist_fdinfo { + int idxplus1; /* this is the index +1, so that memset(0) will make it + * a no-such-element */ +}; + +void +event_changelist_init_(struct event_changelist *changelist) +{ + changelist->changes = NULL; + changelist->changes_size = 0; + changelist->n_changes = 0; +} + +/** Helper: return the changelist_fdinfo corresponding to a given change. */ +static inline struct event_changelist_fdinfo * +event_change_get_fdinfo(struct event_base *base, + const struct event_change *change) +{ + char *ptr; + if (change->read_change & EV_CHANGE_SIGNAL) { + struct evmap_signal *ctx; + GET_SIGNAL_SLOT(ctx, &base->sigmap, change->fd, evmap_signal); + ptr = ((char*)ctx) + sizeof(struct evmap_signal); + } else { + struct evmap_io *ctx; + GET_IO_SLOT(ctx, &base->io, change->fd, evmap_io); + ptr = ((char*)ctx) + sizeof(struct evmap_io); + } + return (void*)ptr; +} + +/** Callback helper for event_changelist_assert_ok */ +static int +event_changelist_assert_ok_foreach_iter_fn( + struct event_base *base, + evutil_socket_t fd, struct evmap_io *io, void *arg) +{ + struct event_changelist *changelist = &base->changelist; + struct event_changelist_fdinfo *f; + f = (void*) + ( ((char*)io) + sizeof(struct evmap_io) ); + if (f->idxplus1) { + struct event_change *c = &changelist->changes[f->idxplus1 - 1]; + EVUTIL_ASSERT(c->fd == fd); + } + return 0; +} + +/** Make sure that the changelist is consistent with the evmap structures. */ +static void +event_changelist_assert_ok(struct event_base *base) +{ + int i; + struct event_changelist *changelist = &base->changelist; + + EVUTIL_ASSERT(changelist->changes_size >= changelist->n_changes); + for (i = 0; i < changelist->n_changes; ++i) { + struct event_change *c = &changelist->changes[i]; + struct event_changelist_fdinfo *f; + EVUTIL_ASSERT(c->fd >= 0); + f = event_change_get_fdinfo(base, c); + EVUTIL_ASSERT(f); + EVUTIL_ASSERT(f->idxplus1 == i + 1); + } + + evmap_io_foreach_fd(base, + event_changelist_assert_ok_foreach_iter_fn, + NULL); +} + +#ifdef DEBUG_CHANGELIST +#define event_changelist_check(base) event_changelist_assert_ok((base)) +#else +#define event_changelist_check(base) ((void)0) +#endif + +void +event_changelist_remove_all_(struct event_changelist *changelist, + struct event_base *base) +{ + int i; + + event_changelist_check(base); + + for (i = 0; i < changelist->n_changes; ++i) { + struct event_change *ch = &changelist->changes[i]; + struct event_changelist_fdinfo *fdinfo = + event_change_get_fdinfo(base, ch); + EVUTIL_ASSERT(fdinfo->idxplus1 == i + 1); + fdinfo->idxplus1 = 0; + } + + changelist->n_changes = 0; + + event_changelist_check(base); +} + +void +event_changelist_freemem_(struct event_changelist *changelist) +{ + if (changelist->changes) + mm_free(changelist->changes); + event_changelist_init_(changelist); /* zero it all out. */ +} + +/** Increase the size of 'changelist' to hold more changes. */ +static int +event_changelist_grow(struct event_changelist *changelist) +{ + int new_size; + struct event_change *new_changes; + if (changelist->changes_size < 64) + new_size = 64; + else + new_size = changelist->changes_size * 2; + + new_changes = mm_realloc(changelist->changes, + new_size * sizeof(struct event_change)); + + if (EVUTIL_UNLIKELY(new_changes == NULL)) + return (-1); + + changelist->changes = new_changes; + changelist->changes_size = new_size; + + return (0); +} + +/** Return a pointer to the changelist entry for the file descriptor or signal + * 'fd', whose fdinfo is 'fdinfo'. If none exists, construct it, setting its + * old_events field to old_events. + */ +static struct event_change * +event_changelist_get_or_construct(struct event_changelist *changelist, + evutil_socket_t fd, + short old_events, + struct event_changelist_fdinfo *fdinfo) +{ + struct event_change *change; + + if (fdinfo->idxplus1 == 0) { + int idx; + EVUTIL_ASSERT(changelist->n_changes <= changelist->changes_size); + + if (changelist->n_changes == changelist->changes_size) { + if (event_changelist_grow(changelist) < 0) + return NULL; + } + + idx = changelist->n_changes++; + change = &changelist->changes[idx]; + fdinfo->idxplus1 = idx + 1; + + memset(change, 0, sizeof(struct event_change)); + change->fd = fd; + change->old_events = old_events; + } else { + change = &changelist->changes[fdinfo->idxplus1 - 1]; + EVUTIL_ASSERT(change->fd == fd); + } + return change; +} + +int +event_changelist_add_(struct event_base *base, evutil_socket_t fd, short old, short events, + void *p) +{ + struct event_changelist *changelist = &base->changelist; + struct event_changelist_fdinfo *fdinfo = p; + struct event_change *change; + + event_changelist_check(base); + + change = event_changelist_get_or_construct(changelist, fd, old, fdinfo); + if (!change) + return -1; + + /* An add replaces any previous delete, but doesn't result in a no-op, + * since the delete might fail (because the fd had been closed since + * the last add, for instance. */ + + if (events & (EV_READ|EV_SIGNAL)) { + change->read_change = EV_CHANGE_ADD | + (events & (EV_ET|EV_PERSIST|EV_SIGNAL)); + } + if (events & EV_WRITE) { + change->write_change = EV_CHANGE_ADD | + (events & (EV_ET|EV_PERSIST|EV_SIGNAL)); + } + if (events & EV_CLOSED) { + change->close_change = EV_CHANGE_ADD | + (events & (EV_ET|EV_PERSIST|EV_SIGNAL)); + } + + event_changelist_check(base); + return (0); +} + +int +event_changelist_del_(struct event_base *base, evutil_socket_t fd, short old, short events, + void *p) +{ + struct event_changelist *changelist = &base->changelist; + struct event_changelist_fdinfo *fdinfo = p; + struct event_change *change; + + event_changelist_check(base); + change = event_changelist_get_or_construct(changelist, fd, old, fdinfo); + event_changelist_check(base); + if (!change) + return -1; + + /* A delete on an event set that doesn't contain the event to be + deleted produces a no-op. This effectively emoves any previous + uncommitted add, rather than replacing it: on those platforms where + "add, delete, dispatch" is not the same as "no-op, dispatch", we + want the no-op behavior. + + If we have a no-op item, we could remove it it from the list + entirely, but really there's not much point: skipping the no-op + change when we do the dispatch later is far cheaper than rejuggling + the array now. + + As this stands, it also lets through deletions of events that are + not currently set. + */ + + if (events & (EV_READ|EV_SIGNAL)) { + if (!(change->old_events & (EV_READ | EV_SIGNAL))) + change->read_change = 0; + else + change->read_change = EV_CHANGE_DEL; + } + if (events & EV_WRITE) { + if (!(change->old_events & EV_WRITE)) + change->write_change = 0; + else + change->write_change = EV_CHANGE_DEL; + } + if (events & EV_CLOSED) { + if (!(change->old_events & EV_CLOSED)) + change->close_change = 0; + else + change->close_change = EV_CHANGE_DEL; + } + + event_changelist_check(base); + return (0); +} + +/* Helper for evmap_check_integrity_: verify that all of the events pending on + * given fd are set up correctly, and that the nread and nwrite counts on that + * fd are correct. */ +static int +evmap_io_check_integrity_fn(struct event_base *base, evutil_socket_t fd, + struct evmap_io *io_info, void *arg) +{ + struct event *ev; + int n_read = 0, n_write = 0, n_close = 0; + + /* First, make sure the list itself isn't corrupt. Otherwise, + * running LIST_FOREACH could be an exciting adventure. */ + EVUTIL_ASSERT_LIST_OK(&io_info->events, event, ev_io_next); + + LIST_FOREACH(ev, &io_info->events, ev_io_next) { + EVUTIL_ASSERT(ev->ev_flags & EVLIST_INSERTED); + EVUTIL_ASSERT(ev->ev_fd == fd); + EVUTIL_ASSERT(!(ev->ev_events & EV_SIGNAL)); + EVUTIL_ASSERT((ev->ev_events & (EV_READ|EV_WRITE|EV_CLOSED))); + if (ev->ev_events & EV_READ) + ++n_read; + if (ev->ev_events & EV_WRITE) + ++n_write; + if (ev->ev_events & EV_CLOSED) + ++n_close; + } + + EVUTIL_ASSERT(n_read == io_info->nread); + EVUTIL_ASSERT(n_write == io_info->nwrite); + EVUTIL_ASSERT(n_close == io_info->nclose); + + return 0; +} + +/* Helper for evmap_check_integrity_: verify that all of the events pending + * on given signal are set up correctly. */ +static int +evmap_signal_check_integrity_fn(struct event_base *base, + int signum, struct evmap_signal *sig_info, void *arg) +{ + struct event *ev; + /* First, make sure the list itself isn't corrupt. */ + EVUTIL_ASSERT_LIST_OK(&sig_info->events, event, ev_signal_next); + + LIST_FOREACH(ev, &sig_info->events, ev_io_next) { + EVUTIL_ASSERT(ev->ev_flags & EVLIST_INSERTED); + EVUTIL_ASSERT(ev->ev_fd == signum); + EVUTIL_ASSERT((ev->ev_events & EV_SIGNAL)); + EVUTIL_ASSERT(!(ev->ev_events & (EV_READ|EV_WRITE|EV_CLOSED))); + } + return 0; +} + +void +evmap_check_integrity_(struct event_base *base) +{ + evmap_io_foreach_fd(base, evmap_io_check_integrity_fn, NULL); + evmap_signal_foreach_signal(base, evmap_signal_check_integrity_fn, NULL); + + if (base->evsel->add == event_changelist_add_) + event_changelist_assert_ok(base); +} + +/* Helper type for evmap_foreach_event_: Bundles a function to call on every + * event, and the user-provided void* to use as its third argument. */ +struct evmap_foreach_event_helper { + event_base_foreach_event_cb fn; + void *arg; +}; + +/* Helper for evmap_foreach_event_: calls a provided function on every event + * pending on a given fd. */ +static int +evmap_io_foreach_event_fn(struct event_base *base, evutil_socket_t fd, + struct evmap_io *io_info, void *arg) +{ + struct evmap_foreach_event_helper *h = arg; + struct event *ev; + int r; + LIST_FOREACH(ev, &io_info->events, ev_io_next) { + if ((r = h->fn(base, ev, h->arg))) + return r; + } + return 0; +} + +/* Helper for evmap_foreach_event_: calls a provided function on every event + * pending on a given signal. */ +static int +evmap_signal_foreach_event_fn(struct event_base *base, int signum, + struct evmap_signal *sig_info, void *arg) +{ + struct event *ev; + struct evmap_foreach_event_helper *h = arg; + int r; + LIST_FOREACH(ev, &sig_info->events, ev_signal_next) { + if ((r = h->fn(base, ev, h->arg))) + return r; + } + return 0; +} + +int +evmap_foreach_event_(struct event_base *base, + event_base_foreach_event_cb fn, void *arg) +{ + struct evmap_foreach_event_helper h; + int r; + h.fn = fn; + h.arg = arg; + if ((r = evmap_io_foreach_fd(base, evmap_io_foreach_event_fn, &h))) + return r; + return evmap_signal_foreach_signal(base, evmap_signal_foreach_event_fn, &h); +} + |