diff options
Diffstat (limited to 'libevent/bufferevent_async.c')
| -rw-r--r-- | libevent/bufferevent_async.c | 706 |
1 files changed, 706 insertions, 0 deletions
diff --git a/libevent/bufferevent_async.c b/libevent/bufferevent_async.c new file mode 100644 index 0000000..40c7c5e --- /dev/null +++ b/libevent/bufferevent_async.c @@ -0,0 +1,706 @@ +/* + * Copyright (c) 2009-2012 Niels Provos and Nick Mathewson + * + * All rights reserved. + * + * 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 EVENT__HAVE_SYS_TIME_H +#include <sys/time.h> +#endif + +#include <errno.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#ifdef EVENT__HAVE_STDARG_H +#include <stdarg.h> +#endif +#ifdef EVENT__HAVE_UNISTD_H +#include <unistd.h> +#endif + +#ifdef _WIN32 +#include <winsock2.h> +#include <winerror.h> +#include <ws2tcpip.h> +#endif + +#include <sys/queue.h> + +#include "event2/util.h" +#include "event2/bufferevent.h" +#include "event2/buffer.h" +#include "event2/bufferevent_struct.h" +#include "event2/event.h" +#include "event2/util.h" +#include "event-internal.h" +#include "log-internal.h" +#include "mm-internal.h" +#include "bufferevent-internal.h" +#include "util-internal.h" +#include "iocp-internal.h" + +#ifndef SO_UPDATE_CONNECT_CONTEXT +/* Mingw is sometimes missing this */ +#define SO_UPDATE_CONNECT_CONTEXT 0x7010 +#endif + +/* prototypes */ +static int be_async_enable(struct bufferevent *, short); +static int be_async_disable(struct bufferevent *, short); +static void be_async_destruct(struct bufferevent *); +static int be_async_flush(struct bufferevent *, short, enum bufferevent_flush_mode); +static int be_async_ctrl(struct bufferevent *, enum bufferevent_ctrl_op, union bufferevent_ctrl_data *); + +struct bufferevent_async { + struct bufferevent_private bev; + struct event_overlapped connect_overlapped; + struct event_overlapped read_overlapped; + struct event_overlapped write_overlapped; + size_t read_in_progress; + size_t write_in_progress; + unsigned ok : 1; + unsigned read_added : 1; + unsigned write_added : 1; +}; + +const struct bufferevent_ops bufferevent_ops_async = { + "socket_async", + evutil_offsetof(struct bufferevent_async, bev.bev), + be_async_enable, + be_async_disable, + NULL, /* Unlink */ + be_async_destruct, + bufferevent_generic_adj_timeouts_, + be_async_flush, + be_async_ctrl, +}; + +static inline void +be_async_run_eventcb(struct bufferevent *bev, short what, int options) +{ bufferevent_run_eventcb_(bev, what, options|BEV_TRIG_DEFER_CALLBACKS); } + +static inline void +be_async_trigger_nolock(struct bufferevent *bev, short what, int options) +{ bufferevent_trigger_nolock_(bev, what, options|BEV_TRIG_DEFER_CALLBACKS); } + +static inline int +fatal_error(int err) +{ + switch (err) { + /* We may have already associated this fd with a port. + * Let's hope it's this port, and that the error code + * for doing this neer changes. */ + case ERROR_INVALID_PARAMETER: + return 0; + } + return 1; +} + +static inline struct bufferevent_async * +upcast(struct bufferevent *bev) +{ + struct bufferevent_async *bev_a; + if (!BEV_IS_ASYNC(bev)) + return NULL; + bev_a = EVUTIL_UPCAST(bev, struct bufferevent_async, bev.bev); + return bev_a; +} + +static inline struct bufferevent_async * +upcast_connect(struct event_overlapped *eo) +{ + struct bufferevent_async *bev_a; + bev_a = EVUTIL_UPCAST(eo, struct bufferevent_async, connect_overlapped); + EVUTIL_ASSERT(BEV_IS_ASYNC(&bev_a->bev.bev)); + return bev_a; +} + +static inline struct bufferevent_async * +upcast_read(struct event_overlapped *eo) +{ + struct bufferevent_async *bev_a; + bev_a = EVUTIL_UPCAST(eo, struct bufferevent_async, read_overlapped); + EVUTIL_ASSERT(BEV_IS_ASYNC(&bev_a->bev.bev)); + return bev_a; +} + +static inline struct bufferevent_async * +upcast_write(struct event_overlapped *eo) +{ + struct bufferevent_async *bev_a; + bev_a = EVUTIL_UPCAST(eo, struct bufferevent_async, write_overlapped); + EVUTIL_ASSERT(BEV_IS_ASYNC(&bev_a->bev.bev)); + return bev_a; +} + +static void +bev_async_del_write(struct bufferevent_async *beva) +{ + struct bufferevent *bev = &beva->bev.bev; + + if (beva->write_added) { + beva->write_added = 0; + event_base_del_virtual_(bev->ev_base); + } +} + +static void +bev_async_del_read(struct bufferevent_async *beva) +{ + struct bufferevent *bev = &beva->bev.bev; + + if (beva->read_added) { + beva->read_added = 0; + event_base_del_virtual_(bev->ev_base); + } +} + +static void +bev_async_add_write(struct bufferevent_async *beva) +{ + struct bufferevent *bev = &beva->bev.bev; + + if (!beva->write_added) { + beva->write_added = 1; + event_base_add_virtual_(bev->ev_base); + } +} + +static void +bev_async_add_read(struct bufferevent_async *beva) +{ + struct bufferevent *bev = &beva->bev.bev; + + if (!beva->read_added) { + beva->read_added = 1; + event_base_add_virtual_(bev->ev_base); + } +} + +static void +bev_async_consider_writing(struct bufferevent_async *beva) +{ + size_t at_most; + int limit; + struct bufferevent *bev = &beva->bev.bev; + + /* Don't write if there's a write in progress, or we do not + * want to write, or when there's nothing left to write. */ + if (beva->write_in_progress || beva->bev.connecting) + return; + if (!beva->ok || !(bev->enabled&EV_WRITE) || + !evbuffer_get_length(bev->output)) { + bev_async_del_write(beva); + return; + } + + at_most = evbuffer_get_length(bev->output); + + /* This is safe so long as bufferevent_get_write_max never returns + * more than INT_MAX. That's true for now. XXXX */ + limit = (int)bufferevent_get_write_max_(&beva->bev); + if (at_most >= (size_t)limit && limit >= 0) + at_most = limit; + + if (beva->bev.write_suspended) { + bev_async_del_write(beva); + return; + } + + /* XXXX doesn't respect low-water mark very well. */ + bufferevent_incref_(bev); + if (evbuffer_launch_write_(bev->output, at_most, + &beva->write_overlapped)) { + bufferevent_decref_(bev); + beva->ok = 0; + be_async_run_eventcb(bev, BEV_EVENT_ERROR, 0); + } else { + beva->write_in_progress = at_most; + bufferevent_decrement_write_buckets_(&beva->bev, at_most); + bev_async_add_write(beva); + } +} + +static void +bev_async_consider_reading(struct bufferevent_async *beva) +{ + size_t cur_size; + size_t read_high; + size_t at_most; + int limit; + struct bufferevent *bev = &beva->bev.bev; + + /* Don't read if there is a read in progress, or we do not + * want to read. */ + if (beva->read_in_progress || beva->bev.connecting) + return; + if (!beva->ok || !(bev->enabled&EV_READ)) { + bev_async_del_read(beva); + return; + } + + /* Don't read if we're full */ + cur_size = evbuffer_get_length(bev->input); + read_high = bev->wm_read.high; + if (read_high) { + if (cur_size >= read_high) { + bev_async_del_read(beva); + return; + } + at_most = read_high - cur_size; + } else { + at_most = 16384; /* FIXME totally magic. */ + } + + /* XXXX This over-commits. */ + /* XXXX see also not above on cast on bufferevent_get_write_max_() */ + limit = (int)bufferevent_get_read_max_(&beva->bev); + if (at_most >= (size_t)limit && limit >= 0) + at_most = limit; + + if (beva->bev.read_suspended) { + bev_async_del_read(beva); + return; + } + + bufferevent_incref_(bev); + if (evbuffer_launch_read_(bev->input, at_most, &beva->read_overlapped)) { + beva->ok = 0; + be_async_run_eventcb(bev, BEV_EVENT_ERROR, 0); + bufferevent_decref_(bev); + } else { + beva->read_in_progress = at_most; + bufferevent_decrement_read_buckets_(&beva->bev, at_most); + bev_async_add_read(beva); + } + + return; +} + +static void +be_async_outbuf_callback(struct evbuffer *buf, + const struct evbuffer_cb_info *cbinfo, + void *arg) +{ + struct bufferevent *bev = arg; + struct bufferevent_async *bev_async = upcast(bev); + + /* If we added data to the outbuf and were not writing before, + * we may want to write now. */ + + bufferevent_incref_and_lock_(bev); + + if (cbinfo->n_added) + bev_async_consider_writing(bev_async); + + bufferevent_decref_and_unlock_(bev); +} + +static void +be_async_inbuf_callback(struct evbuffer *buf, + const struct evbuffer_cb_info *cbinfo, + void *arg) +{ + struct bufferevent *bev = arg; + struct bufferevent_async *bev_async = upcast(bev); + + /* If we drained data from the inbuf and were not reading before, + * we may want to read now */ + + bufferevent_incref_and_lock_(bev); + + if (cbinfo->n_deleted) + bev_async_consider_reading(bev_async); + + bufferevent_decref_and_unlock_(bev); +} + +static int +be_async_enable(struct bufferevent *buf, short what) +{ + struct bufferevent_async *bev_async = upcast(buf); + + if (!bev_async->ok) + return -1; + + if (bev_async->bev.connecting) { + /* Don't launch anything during connection attempts. */ + return 0; + } + + if (what & EV_READ) + BEV_RESET_GENERIC_READ_TIMEOUT(buf); + if (what & EV_WRITE) + BEV_RESET_GENERIC_WRITE_TIMEOUT(buf); + + /* If we newly enable reading or writing, and we aren't reading or + writing already, consider launching a new read or write. */ + + if (what & EV_READ) + bev_async_consider_reading(bev_async); + if (what & EV_WRITE) + bev_async_consider_writing(bev_async); + return 0; +} + +static int +be_async_disable(struct bufferevent *bev, short what) +{ + struct bufferevent_async *bev_async = upcast(bev); + /* XXXX If we disable reading or writing, we may want to consider + * canceling any in-progress read or write operation, though it might + * not work. */ + + if (what & EV_READ) { + BEV_DEL_GENERIC_READ_TIMEOUT(bev); + bev_async_del_read(bev_async); + } + if (what & EV_WRITE) { + BEV_DEL_GENERIC_WRITE_TIMEOUT(bev); + bev_async_del_write(bev_async); + } + + return 0; +} + +static void +be_async_destruct(struct bufferevent *bev) +{ + struct bufferevent_async *bev_async = upcast(bev); + struct bufferevent_private *bev_p = BEV_UPCAST(bev); + evutil_socket_t fd; + + EVUTIL_ASSERT(!upcast(bev)->write_in_progress && + !upcast(bev)->read_in_progress); + + bev_async_del_read(bev_async); + bev_async_del_write(bev_async); + + fd = evbuffer_overlapped_get_fd_(bev->input); + if (fd != (evutil_socket_t)EVUTIL_INVALID_SOCKET && + (bev_p->options & BEV_OPT_CLOSE_ON_FREE)) { + evutil_closesocket(fd); + evbuffer_overlapped_set_fd_(bev->input, EVUTIL_INVALID_SOCKET); + } +} + +/* GetQueuedCompletionStatus doesn't reliably yield WSA error codes, so + * we use WSAGetOverlappedResult to translate. */ +static void +bev_async_set_wsa_error(struct bufferevent *bev, struct event_overlapped *eo) +{ + DWORD bytes, flags; + evutil_socket_t fd; + + fd = evbuffer_overlapped_get_fd_(bev->input); + WSAGetOverlappedResult(fd, &eo->overlapped, &bytes, FALSE, &flags); +} + +static int +be_async_flush(struct bufferevent *bev, short what, + enum bufferevent_flush_mode mode) +{ + return 0; +} + +static void +connect_complete(struct event_overlapped *eo, ev_uintptr_t key, + ev_ssize_t nbytes, int ok) +{ + struct bufferevent_async *bev_a = upcast_connect(eo); + struct bufferevent *bev = &bev_a->bev.bev; + evutil_socket_t sock; + + BEV_LOCK(bev); + + EVUTIL_ASSERT(bev_a->bev.connecting); + bev_a->bev.connecting = 0; + sock = evbuffer_overlapped_get_fd_(bev_a->bev.bev.input); + /* XXXX Handle error? */ + setsockopt(sock, SOL_SOCKET, SO_UPDATE_CONNECT_CONTEXT, NULL, 0); + + if (ok) + bufferevent_async_set_connected_(bev); + else + bev_async_set_wsa_error(bev, eo); + + be_async_run_eventcb(bev, ok ? BEV_EVENT_CONNECTED : BEV_EVENT_ERROR, 0); + + event_base_del_virtual_(bev->ev_base); + + bufferevent_decref_and_unlock_(bev); +} + +static void +read_complete(struct event_overlapped *eo, ev_uintptr_t key, + ev_ssize_t nbytes, int ok) +{ + struct bufferevent_async *bev_a = upcast_read(eo); + struct bufferevent *bev = &bev_a->bev.bev; + short what = BEV_EVENT_READING; + ev_ssize_t amount_unread; + BEV_LOCK(bev); + EVUTIL_ASSERT(bev_a->read_in_progress); + + amount_unread = bev_a->read_in_progress - nbytes; + evbuffer_commit_read_(bev->input, nbytes); + bev_a->read_in_progress = 0; + if (amount_unread) + bufferevent_decrement_read_buckets_(&bev_a->bev, -amount_unread); + + if (!ok) + bev_async_set_wsa_error(bev, eo); + + if (bev_a->ok) { + if (ok && nbytes) { + BEV_RESET_GENERIC_READ_TIMEOUT(bev); + be_async_trigger_nolock(bev, EV_READ, 0); + bev_async_consider_reading(bev_a); + } else if (!ok) { + what |= BEV_EVENT_ERROR; + bev_a->ok = 0; + be_async_run_eventcb(bev, what, 0); + } else if (!nbytes) { + what |= BEV_EVENT_EOF; + bev_a->ok = 0; + be_async_run_eventcb(bev, what, 0); + } + } + + bufferevent_decref_and_unlock_(bev); +} + +static void +write_complete(struct event_overlapped *eo, ev_uintptr_t key, + ev_ssize_t nbytes, int ok) +{ + struct bufferevent_async *bev_a = upcast_write(eo); + struct bufferevent *bev = &bev_a->bev.bev; + short what = BEV_EVENT_WRITING; + ev_ssize_t amount_unwritten; + + BEV_LOCK(bev); + EVUTIL_ASSERT(bev_a->write_in_progress); + + amount_unwritten = bev_a->write_in_progress - nbytes; + evbuffer_commit_write_(bev->output, nbytes); + bev_a->write_in_progress = 0; + + if (amount_unwritten) + bufferevent_decrement_write_buckets_(&bev_a->bev, + -amount_unwritten); + + + if (!ok) + bev_async_set_wsa_error(bev, eo); + + if (bev_a->ok) { + if (ok && nbytes) { + BEV_RESET_GENERIC_WRITE_TIMEOUT(bev); + be_async_trigger_nolock(bev, EV_WRITE, 0); + bev_async_consider_writing(bev_a); + } else if (!ok) { + what |= BEV_EVENT_ERROR; + bev_a->ok = 0; + be_async_run_eventcb(bev, what, 0); + } else if (!nbytes) { + what |= BEV_EVENT_EOF; + bev_a->ok = 0; + be_async_run_eventcb(bev, what, 0); + } + } + + bufferevent_decref_and_unlock_(bev); +} + +struct bufferevent * +bufferevent_async_new_(struct event_base *base, + evutil_socket_t fd, int options) +{ + struct bufferevent_async *bev_a; + struct bufferevent *bev; + struct event_iocp_port *iocp; + + options |= BEV_OPT_THREADSAFE; + + if (!(iocp = event_base_get_iocp_(base))) + return NULL; + + if (fd >= 0 && event_iocp_port_associate_(iocp, fd, 1)<0) { + if (fatal_error(GetLastError())) + return NULL; + } + + if (!(bev_a = mm_calloc(1, sizeof(struct bufferevent_async)))) + return NULL; + + bev = &bev_a->bev.bev; + if (!(bev->input = evbuffer_overlapped_new_(fd))) { + mm_free(bev_a); + return NULL; + } + if (!(bev->output = evbuffer_overlapped_new_(fd))) { + evbuffer_free(bev->input); + mm_free(bev_a); + return NULL; + } + + if (bufferevent_init_common_(&bev_a->bev, base, &bufferevent_ops_async, + options)<0) + goto err; + + evbuffer_add_cb(bev->input, be_async_inbuf_callback, bev); + evbuffer_add_cb(bev->output, be_async_outbuf_callback, bev); + + event_overlapped_init_(&bev_a->connect_overlapped, connect_complete); + event_overlapped_init_(&bev_a->read_overlapped, read_complete); + event_overlapped_init_(&bev_a->write_overlapped, write_complete); + + bufferevent_init_generic_timeout_cbs_(bev); + + bev_a->ok = fd >= 0; + + return bev; +err: + bufferevent_free(&bev_a->bev.bev); + return NULL; +} + +void +bufferevent_async_set_connected_(struct bufferevent *bev) +{ + struct bufferevent_async *bev_async = upcast(bev); + bev_async->ok = 1; + /* Now's a good time to consider reading/writing */ + be_async_enable(bev, bev->enabled); +} + +int +bufferevent_async_can_connect_(struct bufferevent *bev) +{ + const struct win32_extension_fns *ext = + event_get_win32_extension_fns_(); + + if (BEV_IS_ASYNC(bev) && + event_base_get_iocp_(bev->ev_base) && + ext && ext->ConnectEx) + return 1; + + return 0; +} + +int +bufferevent_async_connect_(struct bufferevent *bev, evutil_socket_t fd, + const struct sockaddr *sa, int socklen) +{ + BOOL rc; + struct bufferevent_async *bev_async = upcast(bev); + struct sockaddr_storage ss; + const struct win32_extension_fns *ext = + event_get_win32_extension_fns_(); + + EVUTIL_ASSERT(ext && ext->ConnectEx && fd >= 0 && sa != NULL); + + /* ConnectEx() requires that the socket be bound to an address + * with bind() before using, otherwise it will fail. We attempt + * to issue a bind() here, taking into account that the error + * code is set to WSAEINVAL when the socket is already bound. */ + memset(&ss, 0, sizeof(ss)); + if (sa->sa_family == AF_INET) { + struct sockaddr_in *sin = (struct sockaddr_in *)&ss; + sin->sin_family = AF_INET; + sin->sin_addr.s_addr = INADDR_ANY; + } else if (sa->sa_family == AF_INET6) { + struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)&ss; + sin6->sin6_family = AF_INET6; + sin6->sin6_addr = in6addr_any; + } else { + /* Well, the user will have to bind() */ + return -1; + } + if (bind(fd, (struct sockaddr *)&ss, sizeof(ss)) < 0 && + WSAGetLastError() != WSAEINVAL) + return -1; + + event_base_add_virtual_(bev->ev_base); + bufferevent_incref_(bev); + rc = ext->ConnectEx(fd, sa, socklen, NULL, 0, NULL, + &bev_async->connect_overlapped.overlapped); + if (rc || WSAGetLastError() == ERROR_IO_PENDING) + return 0; + + event_base_del_virtual_(bev->ev_base); + bufferevent_decref_(bev); + + return -1; +} + +static int +be_async_ctrl(struct bufferevent *bev, enum bufferevent_ctrl_op op, + union bufferevent_ctrl_data *data) +{ + switch (op) { + case BEV_CTRL_GET_FD: + data->fd = evbuffer_overlapped_get_fd_(bev->input); + return 0; + case BEV_CTRL_SET_FD: { + struct bufferevent_async *bev_a = upcast(bev); + struct event_iocp_port *iocp; + + if (data->fd == evbuffer_overlapped_get_fd_(bev->input)) + return 0; + if (!(iocp = event_base_get_iocp_(bev->ev_base))) + return -1; + if (event_iocp_port_associate_(iocp, data->fd, 1) < 0) { + if (fatal_error(GetLastError())) + return -1; + } + evbuffer_overlapped_set_fd_(bev->input, data->fd); + evbuffer_overlapped_set_fd_(bev->output, data->fd); + bev_a->ok = data->fd >= 0; + return 0; + } + case BEV_CTRL_CANCEL_ALL: { + struct bufferevent_async *bev_a = upcast(bev); + evutil_socket_t fd = evbuffer_overlapped_get_fd_(bev->input); + if (fd != (evutil_socket_t)EVUTIL_INVALID_SOCKET && + (bev_a->bev.options & BEV_OPT_CLOSE_ON_FREE)) { + closesocket(fd); + evbuffer_overlapped_set_fd_(bev->input, EVUTIL_INVALID_SOCKET); + } + bev_a->ok = 0; + return 0; + } + case BEV_CTRL_GET_UNDERLYING: + default: + return -1; + } +} + + |