stream: New library for bidirectional streams (e.g. TCP, SSL, Unix sockets).

This code is heavily based on the vconn code.  Eventually we should make
the stream-based vconns (currently that's all of them) a wrapper around
streams, but I haven't done that yet.

SSL is not implemented yet.

lib/stream-tcp.c

@@ -0,0 +1,137 @@
+/*
+ * Copyright (c) 2008, 2009 Nicira Networks.
+ *
+ * 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 <config.h>
+#include "stream.h"
+#include <errno.h>
+#include <inttypes.h>
+#include <sys/types.h>
+#include <netinet/in.h>
+#include <netinet/tcp.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include "packets.h"
+#include "socket-util.h"
+#include "util.h"
+#include "stream-provider.h"
+#include "stream-fd.h"
+
+#include "vlog.h"
+#define THIS_MODULE VLM_stream_tcp
+
+/* Active TCP. */
+
+static int
+new_tcp_stream(const char *name, int fd, int connect_status,
+              const struct sockaddr_in *remote, struct stream **streamp)
+{
+    struct sockaddr_in local;
+    socklen_t local_len = sizeof local;
+    int on = 1;
+    int retval;
+
+    /* Get the local IP and port information */
+    retval = getsockname(fd, (struct sockaddr *)&local, &local_len);
+    if (retval) {
+        memset(&local, 0, sizeof local);
+    }
+
+    retval = setsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &on, sizeof on);
+    if (retval) {
+        VLOG_ERR("%s: setsockopt(TCP_NODELAY): %s", name, strerror(errno));
+        close(fd);
+        return errno;
+    }
+
+    retval = new_fd_stream(name, fd, connect_status, NULL, streamp);
+    if (!retval) {
+        struct stream *stream = *streamp;
+        stream_set_remote_ip(stream, remote->sin_addr.s_addr);
+        stream_set_remote_port(stream, remote->sin_port);
+        stream_set_local_ip(stream, local.sin_addr.s_addr);
+        stream_set_local_port(stream, local.sin_port);
+    }
+    return retval;
+}
+
+static int
+tcp_open(const char *name, char *suffix, struct stream **streamp)
+{
+    struct sockaddr_in sin;
+    int fd, error;
+
+    error = tcp_open_active(suffix, 0, &sin, &fd);
+    if (fd >= 0) {
+        return new_tcp_stream(name, fd, error, &sin, streamp);
+    } else {
+        VLOG_ERR("%s: connect: %s", name, strerror(error));
+        return error;
+    }
+}
+
+struct stream_class tcp_stream_class = {
+    "tcp",                      /* name */
+    tcp_open,                   /* open */
+    NULL,                       /* close */
+    NULL,                       /* connect */
+    NULL,                       /* recv */
+    NULL,                       /* send */
+    NULL,                       /* wait */
+};
+
+/* Passive TCP. */
+
+static int ptcp_accept(int fd, const struct sockaddr *sa, size_t sa_len,
+                       struct stream **streamp);
+
+static int
+ptcp_open(const char *name UNUSED, char *suffix, struct pstream **pstreamp)
+{
+    int fd;
+
+    fd = tcp_open_passive(suffix, 0);
+    if (fd < 0) {
+        return -fd;
+    } else {
+        return new_fd_pstream("ptcp", fd, ptcp_accept, NULL, pstreamp);
+    }
+}
+
+static int
+ptcp_accept(int fd, const struct sockaddr *sa, size_t sa_len,
+            struct stream **streamp)
+{
+    const struct sockaddr_in *sin = (const struct sockaddr_in *) sa;
+    char name[128];
+
+    if (sa_len == sizeof(struct sockaddr_in) && sin->sin_family == AF_INET) {
+        sprintf(name, "tcp:"IP_FMT, IP_ARGS(&sin->sin_addr));
+        sprintf(strchr(name, '\0'), ":%"PRIu16, ntohs(sin->sin_port));
+    } else {
+        strcpy(name, "tcp");
+    }
+    return new_tcp_stream(name, fd, 0, sin, streamp);
+}
+
+struct pstream_class ptcp_pstream_class = {
+    "ptcp",
+    ptcp_open,
+    NULL,
+    NULL,
+    NULL
+};
+