Imported Upstream version 0.8.0~pre1upstream/0.8.0_pre1

1 files changed, 251 insertions, 0 deletions

diff --git a/src/common/fdset_kqueue.c b/src/common/fdset_kqueue.c
new file mode 100644
index 0000000..c7199ae
--- /dev/null
+++ b/src/common/fdset_kqueue.c
@@ -0,0 +1,251 @@
+/*  Copyright (C) 2011 CZ.NIC, z.s.p.o. <knot-dns@labs.nic.cz>
+
+    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 3 of the License, or
+    (at your option) any later version.
+
+    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, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <config.h>
+
+#ifdef HAVE_KQUEUE
+
+#include <stdint.h>
+#include <string.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <sys/event.h>
+#include <sys/time.h>
+
+#include "fdset_kqueue.h"
+
+#define OS_FDS_CHUNKSIZE 8   /*!< Number of pollfd structs in a chunk. */
+#define OS_FDS_KEEPCHUNKS 32 /*!< Will attempt to free memory when reached. */
+
+struct fdset_t {
+	int kq;
+	struct kevent *events;
+	struct kevent *revents;
+	size_t nfds;
+	size_t reserved;
+	size_t polled;
+};
+
+fdset_t *fdset_kqueue_new()
+{
+	fdset_t *set = malloc(sizeof(fdset_t));
+	if (!set) {
+		return 0;
+	}
+
+	/* Blank memory. */
+	memset(set, 0, sizeof(fdset_t));
+
+	/* Create kqueue fd. */
+	set->kq = kqueue();
+	if (set->kq < 0) {
+		free(set);
+		set = 0;
+	}
+
+	return set;
+}
+
+int fdset_kqueue_destroy(fdset_t * fdset)
+{
+	if(!fdset) {
+		return -1;
+	}
+
+	/* Teardown kqueue. */
+	close(fdset->kq);
+
+	/* OK if NULL. */
+	free(fdset->revents);
+	free(fdset->events);
+	free(fdset);
+	return 0;
+}
+
+int fdset_kqueue_realloc(void **old, size_t oldsize, size_t nsize)
+{
+	void *nmem = malloc(nsize);
+	if (!nmem) {
+		return -1;
+	}
+
+	/* Clear and copy old fdset data. */
+	memset(nmem, 0, nsize);
+	if (oldsize > 0) {
+		memcpy(nmem, *old, oldsize);
+		free(*old);
+	}
+	
+	*old = nmem;
+	return 0;
+}
+
+int fdset_kqueue_add(fdset_t *fdset, int fd, int events)
+{
+	if (!fdset || fd < 0 || events <= 0) {
+		return -1;
+	}
+
+	/* Realloc needed. */
+	if (fdset->nfds == fdset->reserved) {
+		const size_t chunk = OS_FDS_CHUNKSIZE;
+		const size_t nsize = (fdset->reserved + chunk) *
+				     sizeof(struct kevent);
+		const size_t oldsize = fdset->nfds * sizeof(struct kevent);
+		
+		if (fdset_kqueue_realloc(&fdset->events, oldsize, nsize) < 0) {
+			return -1;
+		}
+		
+		if (fdset_kqueue_realloc(&fdset->revents, oldsize, nsize) < 0) {
+			return -1;
+		}
+
+	}
+
+	/* Add to kqueue set. */
+	int evfilt = EVFILT_READ; /*! \todo Map events. */
+	EV_SET(&fdset->events[fdset->nfds], fd, evfilt,
+	       EV_ADD|EV_ENABLE, 0, 0, 0);
+
+	++fdset->nfds;
+	return 0;
+}
+
+int fdset_kqueue_remove(fdset_t *fdset, int fd)
+{
+	if (!fdset || fd < 0) {
+		return -1;
+	}
+	
+	/* Find in set. */
+	int pos = -1;
+	for (int i = 0; i < fdset->nfds; ++i) {
+		if (fdset->events[i].ident == fd) {
+			pos = i;
+			break;
+		}
+	}
+	
+	if (pos < 0) {
+		return -1;
+	}
+	
+	/* Remove filters. */
+	EV_SET(&fdset->events[pos], fd, EVFILT_READ,
+	       EV_DISABLE|EV_DELETE, 0, 0, 0);
+
+	/* Attempt to remove from set. */
+	size_t remaining = ((fdset->nfds - pos) - 1) * sizeof(struct kevent);
+	memmove(fdset->events + pos, fdset->events + (pos + 1), remaining);
+	
+	/* Overwrite current item. */
+	--fdset->nfds;
+
+	/*! \todo Return memory if overallocated (nfds is far lower than reserved). */
+	return 0;
+}
+
+int fdset_kqueue_wait(fdset_t *fdset)
+{
+	if (!fdset || fdset->nfds < 1 || !fdset->events) {
+		return -1;
+	}
+
+	/* Poll new events. */
+	fdset->polled = 0;
+	int nfds = kevent(fdset->kq, fdset->events, fdset->nfds,
+	                  fdset->revents, fdset->nfds, 0);
+
+	/* Check. */
+	if (nfds < 0) {
+		return -1;
+	}
+
+	/* Events array is ordered from 0 to nfds. */
+	fdset->polled = nfds;
+	return nfds;
+}
+
+int fdset_kqueue_begin(fdset_t *fdset, fdset_it_t *it)
+{
+	if (!fdset || !it) {
+		return -1;
+	}
+
+	/* Find first. */
+	it->pos = 0;
+	return fdset_next(fdset, it);
+}
+
+int fdset_kqueue_end(fdset_t *fdset, fdset_it_t *it)
+{
+	if (!fdset || !it || fdset->nfds < 1) {
+		return -1;
+	}
+
+	/* Check for polled events. */
+	if (fdset->polled < 1) {
+		it->fd = -1;
+		it->pos = 0;
+		return -1;
+	}
+
+	/* No end found, ends on the beginning. */
+	size_t nid = fdset->polled - 1;
+	it->fd = fdset->revents[nid].ident;
+	it->pos = nid;
+	it->events = 0; /*! \todo Map events. */
+	return -1;
+}
+
+int fdset_kqueue_next(fdset_t *fdset, fdset_it_t *it)
+{
+	if (!fdset || !it || fdset->nfds < 1) {
+		return -1;
+	}
+
+	/* Check boundaries. */
+	if (it->pos >= fdset->polled) {
+		return -1;
+	}
+
+	/* Select next. */
+	size_t nid = it->pos++;
+	it->fd = fdset->revents[nid].ident;
+	it->events = 0; /*! \todo Map events. */
+	return 0;
+}
+
+const char* fdset_kqueue_method()
+{
+	return "kqueue";
+}
+
+/* Package APIs. */
+struct fdset_backend_t FDSET_KQUEUE = {
+	.fdset_new = fdset_kqueue_new,
+	.fdset_destroy = fdset_kqueue_destroy,
+	.fdset_add = fdset_kqueue_add,
+	.fdset_remove = fdset_kqueue_remove,
+	.fdset_wait = fdset_kqueue_wait,
+	.fdset_begin = fdset_kqueue_begin,
+	.fdset_end = fdset_kqueue_end,
+	.fdset_next = fdset_kqueue_next,
+	.fdset_method = fdset_kqueue_method
+};
+
+#endif