X-Git-Url: http://git.archive.openwrt.org/?p=project%2Flibubox.git;a=blobdiff_plain;f=uloop.c;h=9a77ce49a5a7c2444a768eac3eb5059f52681fb3;hp=2de94f5fa5aa2a55b881989ec8f88c93d49a1f68;hb=0bfb44f590402137bfcf8e65c54638908d5ed6d2;hpb=6a8df07590227de8701d54f20f2331a9ba5030d1;ds=sidebyside diff --git a/uloop.c b/uloop.c index 2de94f5..9a77ce4 100644 --- a/uloop.c +++ b/uloop.c @@ -1,24 +1,20 @@ /* - * Copyright (C) 2010 Felix Fietkau - * Copyright (C) 2010 John Crispin - * Copyright (C) 2010 Steven Barth + * uloop - event loop implementation * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation; either version 2 of the License, or - * (at your option) any later version. + * Copyright (C) 2010-2013 Felix Fietkau * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA. + * Permission to use, copy, modify, and/or distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. * + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR + * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN + * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF + * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */ - #include #include @@ -42,6 +38,19 @@ #endif #include +struct uloop_fd_event { + struct uloop_fd *fd; + unsigned int events; +}; + +struct uloop_fd_stack { + struct uloop_fd_stack *next; + struct uloop_fd *fd; + unsigned int events; +}; + +static struct uloop_fd_stack *fd_stack = NULL; + #define ULOOP_MAX_EVENTS 10 static struct list_head timeouts = LIST_HEAD_INIT(timeouts); @@ -49,14 +58,18 @@ static struct list_head processes = LIST_HEAD_INIT(processes); static int poll_fd = -1; bool uloop_cancelled = false; -bool uloop_handle_sigchld = true; static bool do_sigchld = false; + +static struct uloop_fd_event cur_fds[ULOOP_MAX_EVENTS]; static int cur_fd, cur_nfds; #ifdef USE_KQUEUE int uloop_init(void) { + struct timespec timeout = { 0, 0 }; + struct kevent ev = {}; + if (poll_fd >= 0) return 0; @@ -64,6 +77,9 @@ int uloop_init(void) if (poll_fd < 0) return -1; + EV_SET(&ev, SIGCHLD, EVFILT_SIGNAL, EV_ADD, 0, 0, 0); + kevent(poll_fd, &ev, 1, NULL, 0, &timeout); + return 0; } @@ -84,45 +100,58 @@ static uint16_t get_flags(unsigned int flags, unsigned int mask) static struct kevent events[ULOOP_MAX_EVENTS]; -static int register_poll(struct uloop_fd *fd, unsigned int flags) +static int register_kevent(struct uloop_fd *fd, unsigned int flags) { struct timespec timeout = { 0, 0 }; struct kevent ev[2]; int nev = 0; unsigned int fl = 0; + unsigned int changed; uint16_t kflags; - kflags = get_flags(flags, ULOOP_READ); - EV_SET(&ev[nev++], fd->fd, EVFILT_READ, kflags, 0, 0, fd); + if (flags & ULOOP_EDGE_DEFER) + flags &= ~ULOOP_EDGE_TRIGGER; + + changed = flags ^ fd->flags; + if (changed & ULOOP_EDGE_TRIGGER) + changed |= flags; + + if (changed & ULOOP_READ) { + kflags = get_flags(flags, ULOOP_READ); + EV_SET(&ev[nev++], fd->fd, EVFILT_READ, kflags, 0, 0, fd); + } - kflags = get_flags(flags, ULOOP_WRITE); - EV_SET(&ev[nev++], fd->fd, EVFILT_WRITE, kflags, 0, 0, fd); + if (changed & ULOOP_WRITE) { + kflags = get_flags(flags, ULOOP_WRITE); + EV_SET(&ev[nev++], fd->fd, EVFILT_WRITE, kflags, 0, 0, fd); + } if (!flags) fl |= EV_DELETE; - if (nev && (kevent(poll_fd, ev, nev, NULL, fl, &timeout) == -1)) + fd->flags = flags; + if (kevent(poll_fd, ev, nev, NULL, fl, &timeout) == -1) return -1; return 0; } -int uloop_fd_delete(struct uloop_fd *sock) +static int register_poll(struct uloop_fd *fd, unsigned int flags) { - int i; - - for (i = cur_fd + 1; i < cur_nfds; i++) { - if (events[i].udata != sock) - continue; + if (flags & ULOOP_EDGE_TRIGGER) + flags |= ULOOP_EDGE_DEFER; + else + flags &= ~ULOOP_EDGE_DEFER; - events[i].udata = NULL; - } + return register_kevent(fd, flags); +} - sock->registered = false; - return register_poll(sock, 0); +static int __uloop_fd_delete(struct uloop_fd *fd) +{ + return register_poll(fd, 0); } -static void uloop_run_events(int timeout) +static int uloop_fetch_events(int timeout) { struct timespec ts; int nfds, n; @@ -133,17 +162,19 @@ static void uloop_run_events(int timeout) } nfds = kevent(poll_fd, NULL, 0, events, ARRAY_SIZE(events), timeout >= 0 ? &ts : NULL); - for(n = 0; n < nfds; ++n) - { + for (n = 0; n < nfds; n++) { + struct uloop_fd_event *cur = &cur_fds[n]; struct uloop_fd *u = events[n].udata; unsigned int ev = 0; + cur->fd = u; if (!u) continue; if (events[n].flags & EV_ERROR) { u->error = true; - uloop_fd_delete(u); + if (!(u->flags & ULOOP_ERROR_CB)) + uloop_fd_delete(u); } if(events[n].filter == EVFILT_READ) @@ -154,15 +185,16 @@ static void uloop_run_events(int timeout) if (events[n].flags & EV_EOF) u->eof = true; else if (!ev) - continue; + cur->fd = NULL; - if (u->cb) { - cur_fd = n; - cur_nfds = nfds; - u->cb(u, ev); + cur->events = ev; + if (u->flags & ULOOP_EDGE_DEFER) { + u->flags &= ~ULOOP_EDGE_DEFER; + u->flags |= ULOOP_EDGE_TRIGGER; + register_kevent(u, u->flags); } } - cur_nfds = 0; + return nfds; } #endif @@ -207,46 +239,43 @@ static int register_poll(struct uloop_fd *fd, unsigned int flags) ev.data.fd = fd->fd; ev.data.ptr = fd; + fd->flags = flags; return epoll_ctl(poll_fd, op, fd->fd, &ev); } static struct epoll_event events[ULOOP_MAX_EVENTS]; -int uloop_fd_delete(struct uloop_fd *sock) +static int __uloop_fd_delete(struct uloop_fd *sock) { - int i; - - for (i = cur_fd + 1; i < cur_nfds; i++) { - if (events[i].data.ptr != sock) - continue; - - events[i].data.ptr = NULL; - } - sock->registered = false; + sock->flags = 0; return epoll_ctl(poll_fd, EPOLL_CTL_DEL, sock->fd, 0); } -static void uloop_run_events(int timeout) +static int uloop_fetch_events(int timeout) { int n, nfds; nfds = epoll_wait(poll_fd, events, ARRAY_SIZE(events), timeout); - for(n = 0; n < nfds; ++n) - { + for (n = 0; n < nfds; ++n) { + struct uloop_fd_event *cur = &cur_fds[n]; struct uloop_fd *u = events[n].data.ptr; unsigned int ev = 0; + cur->fd = u; if (!u) continue; - if(events[n].events & (EPOLLERR|EPOLLHUP)) { + if (events[n].events & (EPOLLERR|EPOLLHUP)) { u->error = true; - uloop_fd_delete(u); + if (!(u->flags & ULOOP_ERROR_CB)) + uloop_fd_delete(u); } - if(!(events[n].events & (EPOLLRDHUP|EPOLLIN|EPOLLOUT|EPOLLERR|EPOLLHUP))) + if(!(events[n].events & (EPOLLRDHUP|EPOLLIN|EPOLLOUT|EPOLLERR|EPOLLHUP))) { + cur->fd = NULL; continue; + } if(events[n].events & EPOLLRDHUP) u->eof = true; @@ -257,22 +286,92 @@ static void uloop_run_events(int timeout) if(events[n].events & EPOLLOUT) ev |= ULOOP_WRITE; - if(u->cb) { - cur_fd = n; - cur_nfds = nfds; - u->cb(u, ev); - } + cur->events = ev; } - cur_nfds = 0; + + return nfds; } #endif +static bool uloop_fd_stack_event(struct uloop_fd *fd, int events) +{ + struct uloop_fd_stack *cur; + + /* + * Do not buffer events for level-triggered fds, they will keep firing. + * Caller needs to take care of recursion issues. + */ + if (!(fd->flags & ULOOP_EDGE_TRIGGER)) + return false; + + for (cur = fd_stack; cur; cur = cur->next) { + if (cur->fd != fd) + continue; + + if (events < 0) + cur->fd = NULL; + else + cur->events |= events | ULOOP_EVENT_BUFFERED; + + return true; + } + + return false; +} + +static void uloop_run_events(int timeout) +{ + struct uloop_fd_event *cur; + struct uloop_fd *fd; + + if (!cur_nfds) { + cur_fd = 0; + cur_nfds = uloop_fetch_events(timeout); + if (cur_nfds < 0) + cur_nfds = 0; + } + + while (cur_nfds > 0) { + struct uloop_fd_stack stack_cur; + unsigned int events; + + cur = &cur_fds[cur_fd++]; + cur_nfds--; + + fd = cur->fd; + events = cur->events; + if (!fd) + continue; + + if (!fd->cb) + continue; + + if (uloop_fd_stack_event(fd, cur->events)) + continue; + + stack_cur.next = fd_stack; + stack_cur.fd = fd; + fd_stack = &stack_cur; + do { + stack_cur.events = 0; + fd->cb(fd, events); + events = stack_cur.events & ULOOP_EVENT_MASK; + } while (stack_cur.fd && events); + fd_stack = stack_cur.next; + + return; + } +} + int uloop_fd_add(struct uloop_fd *sock, unsigned int flags) { unsigned int fl; int ret; + if (!(flags & (ULOOP_READ | ULOOP_WRITE))) + return uloop_fd_delete(sock); + if (!sock->registered && !(flags & ULOOP_BLOCKING)) { fl = fcntl(sock->fd, F_GETFL, 0); fl |= O_NONBLOCK; @@ -285,11 +384,31 @@ int uloop_fd_add(struct uloop_fd *sock, unsigned int flags) sock->registered = true; sock->eof = false; + sock->error = false; out: return ret; } +int uloop_fd_delete(struct uloop_fd *fd) +{ + int i; + + for (i = 0; i < cur_nfds; i++) { + if (cur_fds[cur_fd + i].fd != fd) + continue; + + cur_fds[cur_fd + i].fd = NULL; + } + + if (!fd->registered) + return 0; + + fd->registered = false; + uloop_fd_stack_event(fd, -1); + return __uloop_fd_delete(fd); +} + static int tv_diff(struct timeval *t1, struct timeval *t2) { return @@ -318,6 +437,15 @@ int uloop_timeout_add(struct uloop_timeout *timeout) return 0; } +static void uloop_gettime(struct timeval *tv) +{ + struct timespec ts; + + clock_gettime(CLOCK_MONOTONIC, &ts); + tv->tv_sec = ts.tv_sec; + tv->tv_usec = ts.tv_nsec / 1000; +} + int uloop_timeout_set(struct uloop_timeout *timeout, int msecs) { struct timeval *time = &timeout->time; @@ -325,7 +453,7 @@ int uloop_timeout_set(struct uloop_timeout *timeout, int msecs) if (timeout->pending) uloop_timeout_cancel(timeout); - gettimeofday(&timeout->time, NULL); + uloop_gettime(&timeout->time); time->tv_sec += msecs / 1000; time->tv_usec += (msecs % 1000) * 1000; @@ -349,6 +477,18 @@ int uloop_timeout_cancel(struct uloop_timeout *timeout) return 0; } +int uloop_timeout_remaining(struct uloop_timeout *timeout) +{ + struct timeval now; + + if (!timeout->pending) + return -1; + + uloop_gettime(&now); + + return tv_diff(&timeout->time, &now); +} + int uloop_process_add(struct uloop_process *p) { struct uloop_process *tmp; @@ -418,19 +558,37 @@ static void uloop_sigchld(int signo) do_sigchld = true; } -static void uloop_setup_signals(void) +static void uloop_install_handler(int signum, void (*handler)(int), struct sigaction* old, bool add) { struct sigaction s; + struct sigaction *act; - memset(&s, 0, sizeof(struct sigaction)); - s.sa_handler = uloop_handle_sigint; - s.sa_flags = 0; - sigaction(SIGINT, &s, NULL); + act = NULL; + sigaction(signum, NULL, &s); - if (uloop_handle_sigchld) { - s.sa_handler = uloop_sigchld; - sigaction(SIGCHLD, &s, NULL); + if (add) { + if (s.sa_handler == SIG_DFL) { /* Do not override existing custom signal handlers */ + memcpy(old, &s, sizeof(struct sigaction)); + s.sa_handler = handler; + s.sa_flags = 0; + act = &s; + } + } + else if (s.sa_handler == handler) { /* Do not restore if someone modified our handler */ + act = old; } + + if (act != NULL) + sigaction(signum, act, NULL); +} + +static void uloop_setup_signals(bool add) +{ + static struct sigaction old_sigint, old_sigchld, old_sigterm; + + uloop_install_handler(SIGINT, uloop_handle_sigint, &old_sigint, add); + uloop_install_handler(SIGTERM, uloop_handle_sigint, &old_sigterm, add); + uloop_install_handler(SIGCHLD, uloop_sigchld, &old_sigchld, add); } static int uloop_get_next_timeout(struct timeval *tv) @@ -483,20 +641,32 @@ static void uloop_clear_processes(void) void uloop_run(void) { + static int recursive_calls = 0; struct timeval tv; - uloop_setup_signals(); + /* + * Handlers are only updated for the first call to uloop_run() (and restored + * when this call is done). + */ + if (!recursive_calls++) + uloop_setup_signals(true); + + uloop_cancelled = false; while(!uloop_cancelled) { - gettimeofday(&tv, NULL); + uloop_gettime(&tv); uloop_process_timeouts(&tv); if (uloop_cancelled) break; if (do_sigchld) uloop_handle_processes(); + uloop_gettime(&tv); uloop_run_events(uloop_get_next_timeout(&tv)); } + + if (!--recursive_calls) + uloop_setup_signals(false); } void uloop_done(void)