1 files changed, 142 insertions, 0 deletions
diff --git a/src/utils-upoll.c b/src/utils-upoll.c
new file mode 100644
index 00000000..af4a6161
--- /dev/null
+++ b/src/utils-upoll.c
@@ -0,0 +1,142 @@
+/*
+ * Copyright 2016 IoT.bzh
+ * Author: José Bollo <jose.bollo@iot.bzh>
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <sys/epoll.h>
+#include <pthread.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <unistd.h>
+#include <assert.h>
+
+#include "utils-upoll.h"
+
+
+struct upoll
+{
+	int fd;
+	void (*process)(void *closure, int fd, uint32_t events);
+	void *closure;
+	struct upoll *next;
+};
+
+static int pollfd = 0;
+static struct upoll *head = NULL;
+static pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER;
+
+int upoll_is_valid(struct upoll *upoll)
+{
+	struct upoll *it = head;
+	while (it != NULL) {
+		if (it == upoll)
+			return 1;
+		it = it->next;
+	}
+	return 0;
+}
+
+struct upoll *upoll_open(int fd, uint32_t events, void (*process)(void *closure, int fd, uint32_t events), void *closure)
+{
+	struct epoll_event e;
+	struct upoll *result;
+	int rc;
+
+	/* opens the epoll stream */
+	if (pollfd == 0) {
+		pollfd = epoll_create1(EPOLL_CLOEXEC);
+		if (pollfd == 0) {
+			pollfd = dup(0);
+			close(0);
+		}
+		if (pollfd < 0) {
+			pollfd = 0;
+			return NULL;
+		}
+	}
+
+	/* allocates */
+	result = malloc(sizeof *result);
+	if (result == NULL)
+		return NULL;
+
+	/* init */
+	result->fd = fd;
+	result->process = process;
+	result->closure = closure;
+	pthread_mutex_lock(&mutex);
+	result->next = head;
+	head = result;
+	pthread_mutex_unlock(&mutex);
+
+	/* records */
+	e.events = events;
+	e.data.ptr = result;
+	rc = epoll_ctl(pollfd, EPOLL_CTL_ADD, fd, &e);
+	if (rc == 0)
+		return result;
+
+	/* revert on error */
+	rc = errno;
+	upoll_close(result);
+	errno = rc;
+	return NULL;
+}
+
+int upoll_update(struct upoll *upoll, uint32_t events)
+{
+	struct epoll_event e;
+
+	assert(pollfd != 0);
+	assert(upoll_is_valid(upoll));
+
+	e.events = events;
+	e.data.ptr = upoll;
+	return epoll_ctl(pollfd, EPOLL_CTL_MOD, upoll->fd, &e);
+}
+
+void upoll_close(struct upoll *upoll)
+{
+	struct upoll **it;
+
+	assert(pollfd != 0);
+	assert(upoll_is_valid(upoll));
+
+	epoll_ctl(pollfd, EPOLL_CTL_DEL, upoll->fd, NULL);
+	pthread_mutex_lock(&mutex);
+	it = &head;
+	while (*it != upoll)
+		it = &(*it)->next;
+	*it = upoll->next;
+	pthread_mutex_unlock(&mutex);
+	free(upoll);
+}
+
+void upoll_wait(int timeout)
+{
+	int rc;
+	struct epoll_event e;
+	struct upoll *upoll;
+
+	if (pollfd == 0)
+		return;
+
+	rc = epoll_wait(pollfd, &e, 1, timeout);
+	if (rc == 1) {
+		upoll = e.data.ptr;
+		upoll->process(upoll->closure, upoll->fd, e.events);
+	}
+}
+