add iom_requeue

io.h

@@ -249,12 +249,16 @@ enum {
   IOM_WRITE=2,
   IOM_ERROR=4
 };
+/* signal interest in events from a socket */
 /* return -1 if error, events can be IOM_READ or IOM_WRITE */
 int iom_add(iomux_t* c,int64 s,unsigned int events);
 
+/* signal interest in more events from a socket */
+int iom_requeue(iomux_t* c,int64 s,unsigned int events);
+
 /* Blocking wait for single event, timeout in milliseconds */
 /* return -1 if error, 0 if ok; s set to fd, revents set to known events on that fd */
-/* when done with the fd, call iom_add on it again! */
+/* when done with the fd, call iom_requeue on it to receive more events! */
 /* This can be called by multiple threads in parallel */
 int iom_wait(iomux_t* c,int64* s,unsigned int* revents,unsigned long timeout);
 

io/iom_requeue.c

@@ -0,0 +1,28 @@
+#include "io_internal.h"
+#ifdef HAVE_EPOLL
+#include <sys/epoll.h>
+#endif
+#ifdef HAVE_KQUEUE
+#include <sys/types.h>
+#include <sys/event.h>
+#include <sys/time.h>
+#endif
+
+int iom_requeue(iomux_t* c,int64 s,unsigned int events) {
+#ifdef HAVE_EPOLL
+  struct epoll_event e = { .events=EPOLLONESHOT, .data.fd=s };
+  if (events & IOM_READ) e.events|=EPOLLIN;
+  if (events & IOM_WRITE) e.events|=EPOLLOUT;
+  return epoll_ctl(c->ctx, EPOLL_CTL_MOD, s, &e);
+#elif defined(HAVE_KQUEUE)
+  struct kevent kev;
+  struct timespec ts = { 0 };
+  EV_SET(&kev, s,
+	 (events & IOM_READ ? EVFILT_READ : 0) +
+	 (events & IOM_WRITE ? EVFILT_WRITE : 0),
+	 EV_ADD | EV_ENABLE | EV_ONESHOT, 0, 0, (void*)s);
+  return kevent(c->ctx, &kev, 1, 0, 0, &ts);
+#else
+#warning "only epoll and kqueue supported for now"
+#endif
+}