X-Git-Url: http://git.archive.openwrt.org/?p=project%2Flibubox.git;a=blobdiff_plain;f=uloop.c;h=8517366a55f19154b25a67dd21ce1e08f09e1589;hp=e9f8d52a2143f05418e761ae01c8c1d4db3020c5;hb=729f47fd5279f902986457682f8f166c324eafb5;hpb=db19e64c1a8149a4240f4029fad9c6da6e3aad3f diff --git a/uloop.c b/uloop.c index e9f8d52..8517366 100644 --- a/uloop.c +++ b/uloop.c @@ -1,36 +1,23 @@ /* - * 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) 2010-2016 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 -#include "uloop.h" - -#ifdef USE_KQUEUE -#include -#endif -#ifdef USE_EPOLL -#include -#endif - #include #include #include @@ -38,204 +25,193 @@ #include #include #include -#include #include -#ifndef ARRAY_SIZE -#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0])) -#endif -#define ULOOP_MAX_EVENTS 10 - -struct uloop_timeout *first_timeout; -static int poll_fd; -bool uloop_cancelled = false; +#include "uloop.h" +#include "utils.h" #ifdef USE_KQUEUE +#include +#endif +#ifdef USE_EPOLL +#include +#endif +#include -int uloop_init(void) -{ - poll_fd = kqueue(); - if (poll_fd < 0) - return -1; +struct uloop_fd_event { + struct uloop_fd *fd; + unsigned int events; +}; - return 0; -} +struct uloop_fd_stack { + struct uloop_fd_stack *next; + struct uloop_fd *fd; + unsigned int events; +}; +static struct uloop_fd_stack *fd_stack = NULL; -static uint16_t get_flags(unsigned int flags, unsigned int mask) -{ - uint16_t kflags = 0; +#define ULOOP_MAX_EVENTS 10 - if (!(flags & mask)) - return EV_DELETE; +static struct list_head timeouts = LIST_HEAD_INIT(timeouts); +static struct list_head processes = LIST_HEAD_INIT(processes); - kflags = EV_ADD; - if (flags & ULOOP_EDGE_TRIGGER) - kflags |= EV_CLEAR; +static int poll_fd = -1; +bool uloop_cancelled = false; +bool uloop_handle_sigchld = true; +static int uloop_status = 0; +static bool do_sigchld = false; - return kflags; -} +static struct uloop_fd_event cur_fds[ULOOP_MAX_EVENTS]; +static int cur_fd, cur_nfds; +static int uloop_run_depth = 0; -static int register_poll(struct uloop_fd *fd, unsigned int flags) -{ - struct timespec timeout = { 0, 0 }; - struct kevent ev[2]; - unsigned int changed; - int nev = 0; - - changed = fd->kqflags ^ flags; - if (changed & ULOOP_EDGE_TRIGGER) - changed |= flags; - - if (changed & ULOOP_READ) { - uint16_t kflags = get_flags(flags, ULOOP_READ); - EV_SET(&ev[nev++], fd->fd, EVFILT_READ, kflags, 0, 0, fd); - } +int uloop_fd_add(struct uloop_fd *sock, unsigned int flags); - if (changed & ULOOP_WRITE) { - uint16_t kflags = get_flags(flags, ULOOP_WRITE); - EV_SET(&ev[nev++], fd->fd, EVFILT_WRITE, kflags, 0, 0, fd); - } +#ifdef USE_KQUEUE +#include "uloop-kqueue.c" +#endif - if (nev && (kevent(poll_fd, ev, nev, NULL, 0, &timeout) == -1)) - return -1; +#ifdef USE_EPOLL +#include "uloop-epoll.c" +#endif - fd->kqflags = flags; - return 0; +static void waker_consume(struct uloop_fd *fd, unsigned int events) +{ + char buf[4]; + + while (read(fd->fd, buf, 4) > 0) + ; } -int uloop_fd_delete(struct uloop_fd *sock) +static int waker_pipe = -1; +static struct uloop_fd waker_fd = { + .fd = -1, + .cb = waker_consume, +}; + +static void waker_init_fd(int fd) { - sock->registered = false; - return register_poll(sock, 0); + fcntl(fd, F_SETFD, fcntl(fd, F_GETFD) | FD_CLOEXEC); + fcntl(fd, F_SETFL, fcntl(fd, F_GETFL) | O_NONBLOCK); } -static void uloop_run_events(int timeout) +static int waker_init(void) { - struct kevent events[ULOOP_MAX_EVENTS]; - struct timespec ts; - int nfds, n; - - if (timeout > 0) { - ts.tv_sec = timeout / 1000; - ts.tv_nsec = timeout * 1000000; - } + int fds[2]; - nfds = kevent(poll_fd, NULL, 0, events, ARRAY_SIZE(events), timeout > 0 ? &ts : NULL); - for(n = 0; n < nfds; ++n) - { - struct uloop_fd *u = events[n].udata; - unsigned int ev = 0; + if (waker_pipe >= 0) + return 0; - if(events[n].flags & EV_ERROR) { - u->error = true; - uloop_fd_delete(u); - } + if (pipe(fds) < 0) + return -1; - if(events[n].filter == EVFILT_READ) - ev |= ULOOP_READ; - else if (events[n].filter == EVFILT_WRITE) - ev |= ULOOP_WRITE; + waker_init_fd(fds[0]); + waker_init_fd(fds[1]); + waker_pipe = fds[1]; - if(events[n].flags & EV_EOF) - u->eof = true; - else if (!ev) - continue; + waker_fd.fd = fds[0]; + waker_fd.cb = waker_consume; + uloop_fd_add(&waker_fd, ULOOP_READ); - if(u->cb) - u->cb(u, ev); - } + return 0; } -#endif - -#ifdef USE_EPOLL - -/** - * FIXME: uClibc < 0.9.30.3 does not define EPOLLRDHUP for Linux >= 2.6.17 - */ -#ifndef EPOLLRDHUP -#define EPOLLRDHUP 0x2000 -#endif +static void uloop_setup_signals(bool add); int uloop_init(void) { - poll_fd = epoll_create(32); - if (poll_fd < 0) + if (uloop_init_pollfd() < 0) + return -1; + + if (waker_init() < 0) { + uloop_done(); return -1; + } + + uloop_setup_signals(true); - fcntl(poll_fd, F_SETFD, fcntl(poll_fd, F_GETFD) | FD_CLOEXEC); return 0; } -static int register_poll(struct uloop_fd *fd, unsigned int flags) +static bool uloop_fd_stack_event(struct uloop_fd *fd, int events) { - struct epoll_event ev; - int op = fd->registered ? EPOLL_CTL_MOD : EPOLL_CTL_ADD; + struct uloop_fd_stack *cur; - memset(&ev, 0, sizeof(struct epoll_event)); + /* + * 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; - if (flags & ULOOP_READ) - ev.events |= EPOLLIN | EPOLLRDHUP; - - if (flags & ULOOP_WRITE) - ev.events |= EPOLLOUT; - - if (flags & ULOOP_EDGE_TRIGGER) - ev.events |= EPOLLET; + for (cur = fd_stack; cur; cur = cur->next) { + if (cur->fd != fd) + continue; - ev.data.fd = fd->fd; - ev.data.ptr = fd; + if (events < 0) + cur->fd = NULL; + else + cur->events |= events | ULOOP_EVENT_BUFFERED; - return epoll_ctl(poll_fd, op, fd->fd, &ev); -} + return true; + } -int uloop_fd_delete(struct uloop_fd *sock) -{ - sock->registered = false; - return epoll_ctl(poll_fd, EPOLL_CTL_DEL, sock->fd, 0); + return false; } static void uloop_run_events(int timeout) { - struct epoll_event events[ULOOP_MAX_EVENTS]; - int nfds, n; + 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; + } - nfds = epoll_wait(poll_fd, events, ARRAY_SIZE(events), timeout); - for(n = 0; n < nfds; ++n) - { - struct uloop_fd *u = events[n].data.ptr; - unsigned int ev = 0; + while (cur_nfds > 0) { + struct uloop_fd_stack stack_cur; + unsigned int events; - if(events[n].events & EPOLLERR) { - u->error = true; - uloop_fd_delete(u); - } + cur = &cur_fds[cur_fd++]; + cur_nfds--; - if(!(events[n].events & (EPOLLRDHUP|EPOLLIN|EPOLLOUT|EPOLLERR))) + fd = cur->fd; + events = cur->events; + if (!fd) continue; - if(events[n].events & EPOLLRDHUP) - u->eof = true; - - if(events[n].events & EPOLLIN) - ev |= ULOOP_READ; + if (!fd->cb) + continue; - if(events[n].events & EPOLLOUT) - ev |= ULOOP_WRITE; + if (uloop_fd_stack_event(fd, cur->events)) + continue; - if(u->cb) - u->cb(u, ev); + 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; } } -#endif - 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; @@ -248,45 +224,68 @@ 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) { - if (t1->tv_sec != t2->tv_sec) - return (t1->tv_sec - t2->tv_sec) * 1000; - else - return (t1->tv_usec - t2->tv_usec) / 1000; + return + (t1->tv_sec - t2->tv_sec) * 1000 + + (t1->tv_usec - t2->tv_usec) / 1000; } int uloop_timeout_add(struct uloop_timeout *timeout) { - struct uloop_timeout **head = &first_timeout; - struct uloop_timeout *prev = NULL; + struct uloop_timeout *tmp; + struct list_head *h = &timeouts; if (timeout->pending) return -1; - while (*head) { - if (tv_diff(&(*head)->time, &timeout->time) > 0) + list_for_each_entry(tmp, &timeouts, list) { + if (tv_diff(&tmp->time, &timeout->time) > 0) { + h = &tmp->list; break; - - prev = *head; - head = &(*head)->next; + } } - timeout->prev = prev; - timeout->next = *head; - if (timeout->next) - timeout->next->prev = timeout; - *head = timeout; + list_add_tail(&timeout->list, h); timeout->pending = true; 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; @@ -294,14 +293,14 @@ int uloop_timeout_set(struct uloop_timeout *timeout, int msecs) if (timeout->pending) uloop_timeout_cancel(timeout); - gettimeofday(&timeout->time, NULL); + uloop_gettime(time); time->tv_sec += msecs / 1000; - time->tv_usec += msecs % 1000; + time->tv_usec += (msecs % 1000) * 1000; if (time->tv_usec > 1000000) { time->tv_sec++; - time->tv_usec %= 100000; + time->tv_usec -= 1000000; } return uloop_timeout_add(timeout); @@ -312,41 +311,179 @@ int uloop_timeout_cancel(struct uloop_timeout *timeout) if (!timeout->pending) return -1; - if (timeout->prev) - timeout->prev->next = timeout->next; - else - first_timeout = timeout->next; + list_del(&timeout->list); + timeout->pending = false; + + return 0; +} + +int uloop_timeout_remaining(struct uloop_timeout *timeout) +{ + struct timeval now; + + if (!timeout->pending) + return -1; + + uloop_gettime(&now); - if (timeout->next) - timeout->next->prev = timeout->prev; + return tv_diff(&timeout->time, &now); +} - timeout->pending = false; +int uloop_process_add(struct uloop_process *p) +{ + struct uloop_process *tmp; + struct list_head *h = &processes; + + if (p->pending) + return -1; + + list_for_each_entry(tmp, &processes, list) { + if (tmp->pid > p->pid) { + h = &tmp->list; + break; + } + } + + list_add_tail(&p->list, h); + p->pending = true; + + return 0; +} + +int uloop_process_delete(struct uloop_process *p) +{ + if (!p->pending) + return -1; + + list_del(&p->list); + p->pending = false; return 0; } +static void uloop_handle_processes(void) +{ + struct uloop_process *p, *tmp; + pid_t pid; + int ret; + + do_sigchld = false; + + while (1) { + pid = waitpid(-1, &ret, WNOHANG); + if (pid < 0 && errno == EINTR) + continue; + + if (pid <= 0) + return; + + list_for_each_entry_safe(p, tmp, &processes, list) { + if (p->pid < pid) + continue; + + if (p->pid > pid) + break; + + uloop_process_delete(p); + p->cb(p, ret); + } + } + +} + +static void uloop_signal_wake(void) +{ + do { + if (write(waker_pipe, "w", 1) < 0) { + if (errno == EINTR) + continue; + } + break; + } while (1); +} + static void uloop_handle_sigint(int signo) { + uloop_status = signo; uloop_cancelled = true; + uloop_signal_wake(); +} + +static void uloop_sigchld(int signo) +{ + do_sigchld = true; + uloop_signal_wake(); +} + +static void uloop_install_handler(int signum, void (*handler)(int), struct sigaction* old, bool add) +{ + struct sigaction s; + struct sigaction *act; + + act = NULL; + sigaction(signum, NULL, &s); + + 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(void) +static void uloop_ignore_signal(int signum, bool ignore) { struct sigaction s; - memset(&s, 0, sizeof(struct sigaction)); - s.sa_handler = uloop_handle_sigint; - s.sa_flags = 0; - sigaction(SIGINT, &s, NULL); + void *new_handler = NULL; + + sigaction(signum, NULL, &s); + + if (ignore) { + if (s.sa_handler == SIG_DFL) /* Ignore only if there isn't any custom handler */ + new_handler = SIG_IGN; + } else { + if (s.sa_handler == SIG_IGN) /* Restore only if noone modified our SIG_IGN */ + new_handler = SIG_DFL; + } + + if (new_handler) { + s.sa_handler = new_handler; + s.sa_flags = 0; + sigaction(signum, &s, 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); + + if (uloop_handle_sigchld) + uloop_install_handler(SIGCHLD, uloop_sigchld, &old_sigchld, add); + + uloop_ignore_signal(SIGPIPE, add); } static int uloop_get_next_timeout(struct timeval *tv) { + struct uloop_timeout *timeout; int diff; - if (!first_timeout) + if (list_empty(&timeouts)) return -1; - diff = tv_diff(&first_timeout->time, tv); + timeout = list_first_entry(&timeouts, struct uloop_timeout, list); + diff = tv_diff(&timeout->time, tv); if (diff < 0) return 0; @@ -355,33 +492,90 @@ static int uloop_get_next_timeout(struct timeval *tv) static void uloop_process_timeouts(struct timeval *tv) { - struct uloop_timeout *timeout; + struct uloop_timeout *t; + + while (!list_empty(&timeouts)) { + t = list_first_entry(&timeouts, struct uloop_timeout, list); - while (first_timeout) { - if (tv_diff(&first_timeout->time, tv) > 0) + if (tv_diff(&t->time, tv) > 0) break; - timeout = first_timeout; - uloop_timeout_cancel(timeout); - if (timeout->cb) - timeout->cb(timeout); + uloop_timeout_cancel(t); + if (t->cb) + t->cb(t); } } -void uloop_run(void) +static void uloop_clear_timeouts(void) { + struct uloop_timeout *t, *tmp; + + list_for_each_entry_safe(t, tmp, &timeouts, list) + uloop_timeout_cancel(t); +} + +static void uloop_clear_processes(void) +{ + struct uloop_process *p, *tmp; + + list_for_each_entry_safe(p, tmp, &processes, list) + uloop_process_delete(p); +} + +bool uloop_cancelling(void) +{ + return uloop_run_depth > 0 && uloop_cancelled; +} + +int uloop_run_timeout(int timeout) +{ + int next_time = 0; struct timeval tv; - uloop_setup_signals(); - while(!uloop_cancelled) + uloop_run_depth++; + + uloop_status = 0; + uloop_cancelled = false; + while (!uloop_cancelled) { - gettimeofday(&tv, NULL); + uloop_gettime(&tv); uloop_process_timeouts(&tv); - uloop_run_events(uloop_get_next_timeout(&tv)); + + if (do_sigchld) + uloop_handle_processes(); + + if (uloop_cancelled) + break; + + uloop_gettime(&tv); + + next_time = uloop_get_next_timeout(&tv); + if (timeout >= 0 && timeout < next_time) + next_time = timeout; + uloop_run_events(next_time); } + + --uloop_run_depth; + + return uloop_status; } void uloop_done(void) { - close(poll_fd); + uloop_setup_signals(false); + + if (poll_fd >= 0) { + close(poll_fd); + poll_fd = -1; + } + + if (waker_pipe >= 0) { + uloop_fd_delete(&waker_fd); + close(waker_pipe); + close(waker_fd.fd); + waker_pipe = -1; + } + + uloop_clear_timeouts(); + uloop_clear_processes(); }