socket-util: New function xset_nonblocking().

[openvswitch] / lib / socket-util.c

diff --git a/lib/socket-util.c b/lib/socket-util.c
index 219433fb8f4968b0d6260223fe92af6a10c84399..939cd90ff8a8eef55cb809a775c424dadad9d4ac 100644 (file)
--- a/lib/socket-util.c
+++ b/lib/socket-util.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2008, 2009, 2010, 2011 Nicira Networks.
+ * Copyright (c) 2008, 2009, 2010, 2011, 2012 Nicira, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -17,6 +17,7 @@
 #include <config.h>
 #include "socket-util.h"
 #include <arpa/inet.h>
+#include <assert.h>
 #include <errno.h>
 #include <fcntl.h>
 #include <net/if.h>
@@ -81,6 +82,29 @@ set_nonblocking(int fd)
     }
 }
 
+void
+xset_nonblocking(int fd)
+{
+    if (set_nonblocking(fd)) {
+        exit(EXIT_FAILURE);
+    }
+}
+
+static int
+set_dscp(int fd, uint8_t dscp)
+{
+    if (dscp > 63) {
+        return EINVAL;
+    }
+
+    dscp = dscp << 2;
+    if (setsockopt(fd, IPPROTO_IP, IP_TOS, &dscp, sizeof dscp)) {
+        return errno;
+    }
+
+    return 0;
+}
+
 static bool
 rlim_is_finite(rlim_t limit)
 {
@@ -368,12 +392,11 @@ bind_unix_socket(int fd, struct sockaddr *sun, socklen_t sun_len)
 /* Creates a Unix domain socket in the given 'style' (either SOCK_DGRAM or
  * SOCK_STREAM) that is bound to '*bind_path' (if 'bind_path' is non-null) and
  * connected to '*connect_path' (if 'connect_path' is non-null).  If 'nonblock'
- * is true, the socket is made non-blocking.  If 'passcred' is true, the socket
- * is configured to receive SCM_CREDENTIALS control messages.
+ * is true, the socket is made non-blocking.
  *
  * Returns the socket's fd if successful, otherwise a negative errno value. */
 int
-make_unix_socket(int style, bool nonblock, bool passcred OVS_UNUSED,
+make_unix_socket(int style, bool nonblock,
                  const char *bind_path, const char *connect_path)
 {
     int error;
@@ -441,16 +464,6 @@ make_unix_socket(int style, bool nonblock, bool passcred OVS_UNUSED,
         }
     }
 
-#ifdef SCM_CREDENTIALS
-    if (passcred) {
-        int enable = 1;
-        if (setsockopt(fd, SOL_SOCKET, SO_PASSCRED, &enable, sizeof(enable))) {
-            error = errno;
-            goto error;
-        }
-    }
-#endif
-
     return fd;
 
 error:
@@ -458,7 +471,7 @@ error:
         error = EPROTO;
     }
     if (bind_path) {
-        fatal_signal_remove_file_to_unlink(bind_path);
+        fatal_signal_unlink_file_now(bind_path);
     }
     close(fd);
     return -error;
@@ -544,10 +557,14 @@ exit:
  * and stores -1 into '*fdp'.
  *
  * If 'sinp' is non-null, then on success the target address is stored into
- * '*sinp'. */
+ * '*sinp'.
+ *
+ * 'dscp' becomes the DSCP bits in the IP headers for the new connection.  It
+ * should be in the range [0, 63] and will automatically be shifted to the
+ * appropriately place in the IP tos field. */
 int
 inet_open_active(int style, const char *target, uint16_t default_port,
-                 struct sockaddr_in *sinp, int *fdp)
+                 struct sockaddr_in *sinp, int *fdp, uint8_t dscp)
 {
     struct sockaddr_in sin;
     int fd = -1;
@@ -568,31 +585,33 @@ inet_open_active(int style, const char *target, uint16_t default_port,
     }
     error = set_nonblocking(fd);
     if (error) {
-        goto exit_close;
+        goto exit;
+    }
+
+    /* The dscp bits must be configured before connect() to ensure that the TOS
+     * field is set during the connection establishment.  If set after
+     * connect(), the handshake SYN frames will be sent with a TOS of 0. */
+    error = set_dscp(fd, dscp);
+    if (error) {
+        VLOG_ERR("%s: socket: %s", target, strerror(error));
+        goto exit;
     }
 
     /* Connect. */
     error = connect(fd, (struct sockaddr *) &sin, sizeof sin) == 0 ? 0 : errno;
     if (error == EINPROGRESS) {
         error = EAGAIN;
-    } else if (error && error != EAGAIN) {
-        goto exit_close;
     }
 
-    /* Success: error is 0 or EAGAIN. */
-    goto exit;
-
-exit_close:
-    close(fd);
 exit:
     if (!error || error == EAGAIN) {
         if (sinp) {
             *sinp = sin;
         }
-        *fdp = fd;
-    } else {
-        *fdp = -1;
+    } else if (fd >= 0) {
+        close(fd);
     }
+    *fdp = fd;
     return error;
 }
 
@@ -663,10 +682,14 @@ exit:
  * negative errno value.
  *
  * If 'sinp' is non-null, then on success the bound address is stored into
- * '*sinp'. */
+ * '*sinp'.
+ *
+ * 'dscp' becomes the DSCP bits in the IP headers for the new connection.  It
+ * should be in the range [0, 63] and will automatically be shifted to the
+ * appropriately place in the IP tos field. */
 int
 inet_open_passive(int style, const char *target, int default_port,
-                  struct sockaddr_in *sinp)
+                  struct sockaddr_in *sinp, uint8_t dscp)
 {
     struct sockaddr_in sin;
     int fd = 0, error;
@@ -701,8 +724,17 @@ inet_open_passive(int style, const char *target, int default_port,
         goto error;
     }
 
+    /* The dscp bits must be configured before connect() to ensure that the TOS
+     * field is set during the connection establishment.  If set after
+     * connect(), the handshake SYN frames will be sent with a TOS of 0. */
+    error = set_dscp(fd, dscp);
+    if (error) {
+        VLOG_ERR("%s: socket: %s", target, strerror(error));
+        goto error;
+    }
+
     /* Listen. */
-    if (listen(fd, 10) < 0) {
+    if (style == SOCK_STREAM && listen(fd, 10) < 0) {
         error = errno;
         VLOG_ERR("%s: listen: %s", target, strerror(error));
         goto error;