-/* Copyright (C) 2007 Board of Trustees, Leland Stanford Jr. University.
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to
- * deal in the Software without restriction, including without limitation the
- * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
- * sell copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in
- * all copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
- * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
- * IN THE SOFTWARE.
+/* Copyright (c) 2008 The Board of Trustees of The Leland Stanford
+ * Junior University
+ *
+ * We are making the OpenFlow specification and associated documentation
+ * (Software) available for public use and benefit with the expectation
+ * that others will use, modify and enhance the Software and contribute
+ * those enhancements back to the community. However, since we would
+ * like to make the Software available for broadest use, with as few
+ * restrictions as possible permission is hereby granted, free of
+ * charge, to any person obtaining a copy of this Software to deal in
+ * the Software under the copyrights without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ *
+ * The name and trademarks of copyright holder(s) may NOT be used in
+ * advertising or publicity pertaining to the Software or any
+ * derivatives without specific, written prior permission.
*/
+#include <config.h>
#include "socket-util.h"
#include <arpa/inet.h>
#include <errno.h>
#include <fcntl.h>
#include <netdb.h>
+#include <poll.h>
#include <stdio.h>
+#include <string.h>
#include "vlog.h"
#define THIS_MODULE VLM_socket_util
{
int flags = fcntl(fd, F_GETFL, 0);
if (flags != -1) {
- return fcntl(fd, F_SETFL, flags | O_NONBLOCK) != -1 ? 0 : errno;
+ if (fcntl(fd, F_SETFL, flags | O_NONBLOCK) != -1) {
+ return 0;
+ } else {
+ VLOG_ERR("fcntl(F_SETFL) failed: %s", strerror(errno));
+ return errno;
+ }
} else {
+ VLOG_ERR("fcntl(F_GETFL) failed: %s", strerror(errno));
return errno;
}
}
}
return 0;
}
+
+/* Returns the error condition associated with socket 'fd' and resets the
+ * socket's error status. */
+int
+get_socket_error(int fd)
+{
+ int error;
+ socklen_t len = sizeof(error);
+ if (getsockopt(fd, SOL_SOCKET, SO_ERROR, &error, &len) < 0) {
+ error = errno;
+ VLOG_ERR("getsockopt(SO_ERROR): %s", strerror(error));
+ }
+ return error;
+}
+
+int
+check_connection_completion(int fd)
+{
+ struct pollfd pfd;
+ int retval;
+
+ pfd.fd = fd;
+ pfd.events = POLLOUT;
+ do {
+ retval = poll(&pfd, 1, 0);
+ } while (retval < 0 && errno == EINTR);
+ if (retval == 1) {
+ return get_socket_error(fd);
+ } else if (retval < 0) {
+ VLOG_ERR("poll: %s", strerror(errno));
+ return errno;
+ } else {
+ return EAGAIN;
+ }
+}
+
+/* Drain all the data currently in the receive queue of a datagram socket (and
+ * possibly additional data). There is no way to know how many packets are in
+ * the receive queue, but we do know that the total number of bytes queued does
+ * not exceed the receive buffer size, so we pull packets until none are left
+ * or we've read that many bytes. */
+int
+drain_rcvbuf(int fd)
+{
+ socklen_t rcvbuf_len;
+ size_t rcvbuf;
+
+ rcvbuf_len = sizeof rcvbuf;
+ if (getsockopt(fd, SOL_SOCKET, SO_RCVBUF, &rcvbuf, &rcvbuf_len) < 0) {
+ VLOG_ERR("getsockopt(SO_RCVBUF) failed: %s", strerror(errno));
+ return errno;
+ }
+ while (rcvbuf > 0) {
+ /* In Linux, specifying MSG_TRUNC in the flags argument causes the
+ * datagram length to be returned, even if that is longer than the
+ * buffer provided. Thus, we can use a 1-byte buffer to discard the
+ * incoming datagram and still be able to account how many bytes were
+ * removed from the receive buffer.
+ *
+ * On other Unix-like OSes, MSG_TRUNC has no effect in the flags
+ * argument. */
+#ifdef __linux__
+#define BUFFER_SIZE 1
+#else
+#define BUFFER_SIZE 2048
+#endif
+ char buffer[BUFFER_SIZE];
+ ssize_t n_bytes = recv(fd, buffer, sizeof buffer,
+ MSG_TRUNC | MSG_DONTWAIT);
+ if (n_bytes <= 0 || n_bytes >= rcvbuf) {
+ break;
+ }
+ rcvbuf -= n_bytes;
+ }
+ return 0;
+}
projects / openvswitch / blobdiff