X-Git-Url: http://git.ozlabs.org/?p=ccan;a=blobdiff_plain;f=ccan%2Fio%2Fpoll.c;h=b005a97e4b1d07879a4e281a8d48276baaac2fa1;hp=9f9bb4a256168699eecec1dc062855475766e899;hb=e2d15a2bcb78dba323c4a807543fcc0cb1b03ef0;hpb=d0458a433876acc01b48f74c1c3b966bbc29de57 diff --git a/ccan/io/poll.c b/ccan/io/poll.c index 9f9bb4a2..b005a97e 100644 --- a/ccan/io/poll.c +++ b/ccan/io/poll.c @@ -7,32 +7,61 @@ #include #include #include +#include +#include +#include -static size_t num_fds = 0, max_fds = 0, num_closing = 0, num_waiting = 0; +static size_t num_fds = 0, max_fds = 0, num_waiting = 0; static struct pollfd *pollfds = NULL; static struct fd **fds = NULL; -static struct timers timeouts; +static LIST_HEAD(closing); +static LIST_HEAD(always); +static struct timemono (*nowfn)(void) = time_mono; +static int (*pollfn)(struct pollfd *fds, nfds_t nfds, int timeout) = poll; + +struct timemono (*io_time_override(struct timemono (*now)(void)))(void) +{ + struct timemono (*old)(void) = nowfn; + nowfn = now; + return old; +} + +int (*io_poll_override(int (*poll)(struct pollfd *fds, nfds_t nfds, int timeout)))(struct pollfd *, nfds_t, int) +{ + int (*old)(struct pollfd *fds, nfds_t nfds, int timeout) = pollfn; + pollfn = poll; + return old; +} static bool add_fd(struct fd *fd, short events) { + if (!max_fds) { + assert(num_fds == 0); + pollfds = tal_arr(NULL, struct pollfd, 8); + if (!pollfds) + return false; + fds = tal_arr(pollfds, struct fd *, 8); + if (!fds) + return false; + max_fds = 8; + } + if (num_fds + 1 > max_fds) { - struct pollfd *newpollfds; - struct fd **newfds; - size_t num = max_fds ? max_fds * 2 : 8; + size_t num = max_fds * 2; - newpollfds = realloc(pollfds, sizeof(*newpollfds) * num); - if (!newpollfds) + if (!tal_resize(&pollfds, num)) return false; - pollfds = newpollfds; - newfds = realloc(fds, sizeof(*newfds) * num); - if (!newfds) + if (!tal_resize(&fds, num)) return false; - fds = newfds; max_fds = num; } - pollfds[num_fds].fd = fd->fd; pollfds[num_fds].events = events; + /* In case it's idle. */ + if (!events) + pollfds[num_fds].fd = -fd->fd; + else + pollfds[num_fds].fd = fd->fd; pollfds[num_fds].revents = 0; /* In case we're iterating now */ fds[num_fds] = fd; fd->backend_info = num_fds; @@ -59,87 +88,119 @@ static void del_fd(struct fd *fd) fds[n]->backend_info = n; } else if (num_fds == 1) { /* Free everything when no more fds. */ - free(pollfds); - free(fds); - pollfds = NULL; + pollfds = tal_free(pollfds); fds = NULL; max_fds = 0; } num_fds--; fd->backend_info = -1; - close(fd->fd); +} + +static void destroy_listener(struct io_listener *l) +{ + close(l->fd.fd); + del_fd(&l->fd); } bool add_listener(struct io_listener *l) { if (!add_fd(&l->fd, POLLIN)) return false; + tal_add_destructor(l, destroy_listener); return true; } -void backend_plan_changed(struct io_conn *conn) +void remove_from_always(struct io_conn *conn) +{ + list_del_init(&conn->always); +} + +void backend_new_always(struct io_conn *conn) +{ + /* In case it's already in always list. */ + list_del(&conn->always); + list_add_tail(&always, &conn->always); +} + +void backend_new_plan(struct io_conn *conn) { struct pollfd *pfd = &pollfds[conn->fd.backend_info]; if (pfd->events) num_waiting--; - pfd->events = conn->plan.pollflag; - if (conn->duplex) { - int mask = conn->duplex->plan.pollflag; - /* You can't *both* read/write. */ - assert(!mask || pfd->events != mask); - pfd->events |= mask; - } - if (pfd->events) - num_waiting++; + pfd->events = 0; + if (conn->plan[IO_IN].status == IO_POLLING_NOTSTARTED + || conn->plan[IO_IN].status == IO_POLLING_STARTED) + pfd->events |= POLLIN; + if (conn->plan[IO_OUT].status == IO_POLLING_NOTSTARTED + || conn->plan[IO_OUT].status == IO_POLLING_STARTED) + pfd->events |= POLLOUT; - if (!conn->plan.next) - num_closing++; + if (pfd->events) { + num_waiting++; + pfd->fd = conn->fd.fd; + } else { + pfd->fd = -conn->fd.fd; + } } -bool add_conn(struct io_conn *c) +void backend_wake(const void *wait) { - if (!add_fd(&c->fd, c->plan.pollflag)) - return false; - /* Immediate close is allowed. */ - if (!c->plan.next) - num_closing++; - return true; + unsigned int i; + + for (i = 0; i < num_fds; i++) { + struct io_conn *c; + + /* Ignore listeners */ + if (fds[i]->listener) + continue; + + c = (void *)fds[i]; + if (c->plan[IO_IN].status == IO_WAITING + && c->plan[IO_IN].arg.u1.const_vp == wait) + io_do_wakeup(c, IO_IN); + + if (c->plan[IO_OUT].status == IO_WAITING + && c->plan[IO_OUT].arg.u1.const_vp == wait) + io_do_wakeup(c, IO_OUT); + } } -bool add_duplex(struct io_conn *c) +static void destroy_conn(struct io_conn *conn, bool close_fd) { - c->fd.backend_info = c->duplex->fd.backend_info; - backend_plan_changed(c); - return true; + int saved_errno = errno; + + if (close_fd) + close(conn->fd.fd); + del_fd(&conn->fd); + /* In case it's on always list, remove it. */ + list_del_init(&conn->always); + + /* errno saved/restored by tal_free itself. */ + if (conn->finish) { + errno = saved_errno; + conn->finish(conn, conn->finish_arg); + } } -static void del_conn(struct io_conn *conn) +static void destroy_conn_close_fd(struct io_conn *conn) { - if (conn->finish) - conn->finish(conn, conn->finish_arg); - if (timeout_active(conn)) - backend_del_timeout(conn); - free(conn->timeout); - if (conn->duplex) { - /* In case fds[] pointed to the other one. */ - fds[conn->fd.backend_info] = &conn->duplex->fd; - conn->duplex->duplex = NULL; - } else - del_fd(&conn->fd); - num_closing--; + destroy_conn(conn, true); } -void del_listener(struct io_listener *l) +bool add_conn(struct io_conn *c) { - del_fd(&l->fd); + if (!add_fd(&c->fd, 0)) + return false; + tal_add_destructor(c, destroy_conn_close_fd); + return true; } -static void set_plan(struct io_conn *conn, struct io_plan plan) +void cleanup_conn_without_close(struct io_conn *conn) { - conn->plan = plan; - backend_plan_changed(conn); + tal_del_destructor(conn, destroy_conn_close_fd); + destroy_conn(conn, false); } static void accept_conn(struct io_listener *l) @@ -149,97 +210,83 @@ static void accept_conn(struct io_listener *l) /* FIXME: What to do here? */ if (fd < 0) return; - l->init(fd, l->arg); + + io_new_conn(l->ctx, fd, l->init, l->arg); } -/* It's OK to miss some, as long as we make progress. */ -static void finish_conns(void) +static bool handle_always(void) { - unsigned int i; + bool ret = false; + struct io_conn *conn; - for (i = 0; !io_loop_return && i < num_fds; i++) { - struct io_conn *c, *duplex; + while ((conn = list_pop(&always, struct io_conn, always)) != NULL) { + assert(conn->plan[IO_IN].status == IO_ALWAYS + || conn->plan[IO_OUT].status == IO_ALWAYS); - if (!num_closing) - break; - - if (fds[i]->listener) - continue; - c = (void *)fds[i]; - for (duplex = c->duplex; c; c = duplex, duplex = NULL) { - if (!c->plan.next) { - del_conn(c); - free(c); - i--; - } - } + /* Re-initialize, for next time. */ + list_node_init(&conn->always); + io_do_always(conn); + ret = true; } -} - -void backend_add_timeout(struct io_conn *conn, struct timespec duration) -{ - if (!timeouts.base) - timers_init(&timeouts, time_now()); - timer_add(&timeouts, &conn->timeout->timer, - time_add(time_now(), duration)); - conn->timeout->conn = conn; -} - -void backend_del_timeout(struct io_conn *conn) -{ - assert(conn->timeout->conn == conn); - timer_del(&timeouts, &conn->timeout->timer); - conn->timeout->conn = NULL; + return ret; } /* This is the main loop. */ -void *io_loop(void) +void *io_loop(struct timers *timers, struct timer **expired) { void *ret; - while (!io_loop_return) { - int i, r, timeout = INT_MAX; - struct timespec now; - - if (timeouts.base) { - struct timespec first; - struct list_head expired; - struct io_timeout *t; + /* if timers is NULL, expired must be. If not, not. */ + assert(!timers == !expired); - now = time_now(); + /* Make sure this is NULL if we exit for some other reason. */ + if (expired) + *expired = NULL; - /* Call functions for expired timers. */ - timers_expire(&timeouts, now, &expired); - while ((t = list_pop(&expired, struct io_timeout, timer.list))) { - struct io_conn *conn = t->conn; - /* Clear, in case timer re-adds */ - t->conn = NULL; - set_plan(conn, t->next(conn, t->next_arg)); - } - - /* Now figure out how long to wait for the next one. */ - if (timer_earliest(&timeouts, &first)) { - uint64_t f = time_to_msec(time_sub(first, now)); - if (f < INT_MAX) - timeout = f; - } - } + while (!io_loop_return) { + int i, r, ms_timeout = -1; - if (num_closing) { - finish_conns(); + if (handle_always()) { /* Could have started/finished more. */ continue; } + /* Everything closed? */ if (num_fds == 0) break; /* You can't tell them all to go to sleep! */ assert(num_waiting); - r = poll(pollfds, num_fds, timeout); - if (r < 0) + if (timers) { + struct timemono now, first; + + now = nowfn(); + + /* Call functions for expired timers. */ + *expired = timers_expire(timers, now); + if (*expired) + break; + + /* Now figure out how long to wait for the next one. */ + if (timer_earliest(timers, &first)) { + uint64_t next; + next = time_to_msec(timemono_between(first, now)); + if (next < INT_MAX) + ms_timeout = next; + else + ms_timeout = INT_MAX; + } + } + + r = pollfn(pollfds, num_fds, ms_timeout); + if (r < 0) { + /* Signals shouldn't break us, unless they set + * io_loop_return. */ + if (errno == EINTR) + continue; break; + } for (i = 0; i < num_fds && !io_loop_return; i++) { struct io_conn *c = (void *)fds[i]; @@ -249,36 +296,28 @@ void *io_loop(void) break; if (fds[i]->listener) { + struct io_listener *l = (void *)fds[i]; if (events & POLLIN) { - accept_conn((void *)c); + accept_conn(l); + r--; + } else if (events & (POLLHUP|POLLNVAL|POLLERR)) { r--; + errno = EBADF; + io_close_listener(l); } } else if (events & (POLLIN|POLLOUT)) { r--; - if (c->duplex) { - int mask = c->duplex->plan.pollflag; - if (events & mask) { - io_ready(c->duplex); - events &= ~mask; - if (!(events&(POLLIN|POLLOUT))) - continue; - } - } - io_ready(c); - } else if (events & POLLHUP) { + io_ready(c, events); + } else if (events & (POLLHUP|POLLNVAL|POLLERR)) { r--; - set_plan(c, io_close(c, NULL)); - if (c->duplex) - set_plan(c->duplex, - io_close(c->duplex, NULL)); + errno = EBADF; + io_close(c); } } } - while (num_closing) - finish_conns(); - ret = io_loop_return; io_loop_return = NULL; + return ret; }