uloop: improve edge trigger reliability on mac os x

[project/libubox.git] / uloop.c

diff --git a/uloop.c b/uloop.c
index 4de26d4..2d7b2c9 100644 (file)
--- a/uloop.c
+++ b/uloop.c
@@ -32,6 +32,7 @@
 #include <stdbool.h>
 
 #include "uloop.h"
+#include "utils.h"
 
 #ifdef USE_KQUEUE
 #include <sys/event.h>
@@ -41,10 +42,6 @@
 #endif
 #include <sys/wait.h>
 
-
-#ifndef ARRAY_SIZE
-#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]))
-#endif
 #define ULOOP_MAX_EVENTS 10
 
 static struct list_head timeouts = LIST_HEAD_INIT(timeouts);
@@ -54,11 +51,15 @@ static int poll_fd = -1;
 bool uloop_cancelled = false;
 bool uloop_handle_sigchld = true;
 static bool do_sigchld = false;
+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;
 
@@ -66,6 +67,9 @@ 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;
 }
 
@@ -84,58 +88,80 @@ static uint16_t get_flags(unsigned int flags, unsigned int mask)
        return kflags;
 }
 
-static int register_poll(struct uloop_fd *fd, unsigned int flags)
+static struct kevent events[ULOOP_MAX_EVENTS];
+
+static int register_kevent(struct uloop_fd *fd, unsigned int flags)
 {
        struct timespec timeout = { 0, 0 };
        struct kevent ev[2];
-       unsigned int changed;
        int nev = 0;
+       unsigned int fl = 0;
+       uint16_t kflags;
 
-       changed = fd->kqflags ^ flags;
-       if (changed & ULOOP_EDGE_TRIGGER)
-               changed |= flags;
+       if (flags & ULOOP_EDGE_DEFER)
+               flags &= ~ULOOP_EDGE_TRIGGER;
 
-       if (changed & ULOOP_READ) {
-               uint16_t kflags = get_flags(flags, ULOOP_READ);
-               EV_SET(&ev[nev++], fd->fd, EVFILT_READ, kflags, 0, 0, fd);
-       }
+       kflags = get_flags(flags, ULOOP_READ);
+       EV_SET(&ev[nev++], fd->fd, EVFILT_READ, kflags, 0, 0, fd);
 
-       if (changed & ULOOP_WRITE) {
-               uint16_t kflags = get_flags(flags, ULOOP_WRITE);
-               EV_SET(&ev[nev++], fd->fd, EVFILT_WRITE, kflags, 0, 0, fd);
-       }
+       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, 0, &timeout) == -1))
+       if (kevent(poll_fd, ev, nev, NULL, fl, &timeout) == -1)
                return -1;
 
-       fd->kqflags = flags;
        return 0;
 }
 
+static int register_poll(struct uloop_fd *fd, unsigned int flags)
+{
+       if (flags & ULOOP_EDGE_TRIGGER)
+               flags |= ULOOP_EDGE_DEFER;
+       else
+               flags &= ~ULOOP_EDGE_DEFER;
+
+       fd->flags = flags;
+       return register_kevent(fd, flags);
+}
+
 int uloop_fd_delete(struct uloop_fd *sock)
 {
+       int i;
+
+       for (i = cur_fd + 1; i < cur_nfds; i++) {
+               if (events[i].udata != sock)
+                       continue;
+
+               events[i].udata = NULL;
+       }
+
        sock->registered = false;
        return register_poll(sock, 0);
 }
 
 static void uloop_run_events(int timeout)
 {
-       struct kevent events[ULOOP_MAX_EVENTS];
        struct timespec ts;
        int nfds, n;
 
-       if (timeout > 0) {
+       if (timeout >= 0) {
                ts.tv_sec = timeout / 1000;
                ts.tv_nsec = (timeout % 1000) * 1000000;
        }
 
-       nfds = kevent(poll_fd, NULL, 0, events, ARRAY_SIZE(events), timeout > 0 ? &ts : NULL);
+       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(events[n].flags & EV_ERROR) {
+               if (!u)
+                       continue;
+
+               if (events[n].flags & EV_ERROR) {
                        u->error = true;
                        uloop_fd_delete(u);
                }
@@ -145,14 +171,22 @@ static void uloop_run_events(int timeout)
                else if (events[n].filter == EVFILT_WRITE)
                        ev |= ULOOP_WRITE;
 
-               if(events[n].flags & EV_EOF)
+               if (events[n].flags & EV_EOF)
                        u->eof = true;
                else if (!ev)
                        continue;
 
-               if(u->cb)
+               if (u->cb) {
+                       cur_fd = n;
+                       cur_nfds = nfds;
                        u->cb(u, ev);
+                       if (u->flags & ULOOP_EDGE_DEFER) {
+                               u->flags &= ~ULOOP_EDGE_DEFER;
+                               register_kevent(u, u->flags);
+                       }
+               }
        }
+       cur_nfds = 0;
 }
 
 #endif
@@ -201,7 +235,6 @@ static int register_poll(struct uloop_fd *fd, unsigned int flags)
        return epoll_ctl(poll_fd, op, fd->fd, &ev);
 }
 
-static int cur_fd, cur_nfds;
 static struct epoll_event events[ULOOP_MAX_EVENTS];
 
 int uloop_fd_delete(struct uloop_fd *sock)
@@ -283,10 +316,9 @@ out:
 
 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)
@@ -320,11 +352,11 @@ int uloop_timeout_set(struct uloop_timeout *timeout, int msecs)
        gettimeofday(&timeout->time, NULL);
 
        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);
@@ -443,9 +475,11 @@ static int uloop_get_next_timeout(struct timeval *tv)
 
 static void uloop_process_timeouts(struct timeval *tv)
 {
-       struct uloop_timeout *t, *tmp;
+       struct uloop_timeout *t;
+
+       while (!list_empty(&timeouts)) {
+               t = list_first_entry(&timeouts, struct uloop_timeout, list);
 
-       list_for_each_entry_safe(t, tmp, &timeouts, list) {
                if (tv_diff(&t->time, tv) > 0)
                        break;