socket-util: Remove DSCP_INVALID.

The DSCP_INVALID flag allowed callers to prevent socket-util from
modify the DSCP bits of newly created sockets.  However, the two
really important callers (implementations of the controller and
manager tables) never used it.  Furthermore, the other callers
would be fine always setting the DSCP bits to zero.  This patch
removes the DSCP_INVALID option in an effort to simplify the code.

Signed-off-by: Ethan Jackson <ethan@nicira.com>

lib/socket-util.c

@@ -546,8 +546,7 @@ exit:
  * If 'sinp' is non-null, then on success the target address is stored into
  * '*sinp'.
  *
- * 'dscp'  If not DSCP_INVALID, its value becomes the DSCP bits in the IP
- * headers for the new connection. */
+ * 'dscp' becomes the DSCP bits in the IP headers for the new connection. */
 int
 inet_open_active(int style, const char *target, uint16_t default_port,
                  struct sockaddr_in *sinp, int *fdp, uint8_t dscp)
@@ -577,12 +576,10 @@ inet_open_active(int style, const char *target, uint16_t default_port,
     /* The socket options set here ensure that the TOS bits are set during
      * the connection establishment.  If set after connect(), the handshake
      * SYN frames will be sent with a TOS of 0. */
-    if (dscp != DSCP_INVALID) {
-        if (setsockopt(fd, IPPROTO_IP, IP_TOS, &dscp, sizeof dscp)) {
-            VLOG_ERR("%s: socket: %s", target, strerror(errno));
-            error = errno;
-            goto exit;
-        }
+    if (setsockopt(fd, IPPROTO_IP, IP_TOS, &dscp, sizeof dscp)) {
+        VLOG_ERR("%s: socket: %s", target, strerror(errno));
+        error = errno;
+        goto exit;
     }
 
     /* Connect. */
@@ -672,8 +669,7 @@ exit:
  * If 'sinp' is non-null, then on success the bound address is stored into
  * '*sinp'.
  *
- * 'dscp'  If not DSCP_INVALID, its value becomes the DSCP bits in the IP
- * headers for the new connection. */
+ * 'dscp' becomes the DSCP bits in the IP headers for the new connection. */
 int
 inet_open_passive(int style, const char *target, int default_port,
                   struct sockaddr_in *sinp, uint8_t dscp)
@@ -714,12 +710,10 @@ inet_open_passive(int style, const char *target, int default_port,
     /* The socket options set here ensure that the TOS bits are set during
      * the connection establishment.  If set after connect(), the handshake
      * SYN frames will be sent with a TOS of 0. */
-    if (dscp != DSCP_INVALID) {
-        if (setsockopt(fd, IPPROTO_IP, IP_TOS, &dscp, sizeof dscp)) {
-            VLOG_ERR("%s: socket: %s", target, strerror(errno));
-            error = errno;
-            goto error;
-        }
+    if (setsockopt(fd, IPPROTO_IP, IP_TOS, &dscp, sizeof dscp)) {
+        VLOG_ERR("%s: socket: %s", target, strerror(errno));
+        error = errno;
+        goto error;
     }
 
     /* Listen. */

lib/socket-util.h

@@ -69,9 +69,4 @@ char *describe_fd(int fd);
  * in <netinet/ip.h> is used.  */
 #define DSCP_DEFAULT IPTOS_PREC_INTERNETCONTROL
 
-/* Invalid dscp value.  If the dscp value will not be used, the dscp value
- * passed must be invalid.  Set to 0xFF as the TOS bits passed can only be
- * 6 bits. */
-#define DSCP_INVALID 0xFF
-
 #endif /* socket-util.h */

lib/stream-provider.h

@@ -65,9 +65,7 @@ struct stream_class {
      *
      * 'suffix' is a copy of 'name' following the colon and may be modified.
      * 'dscp' is the DSCP value that the new connection should use in the IP
-     * packets it sends.  (If no DSCP value should be set in the packet, dscp
-     * will be set to DSCP_INVALID.  If no DSCP value is specified, DSCP_DEFAULT
-     * value will be applied.)
+     * packets it sends.
      *
      * Returns 0 if successful, otherwise a positive errno value.  If
      * successful, stores a pointer to the new connection in '*streamp'.
@@ -167,9 +165,7 @@ struct pstream_class {
      *
      * 'suffix' is a copy of 'name' following the colon and may be modified.
      * 'dscp' is the DSCP value that the new connection should use in the IP
-     * packets it sends.  (If no DSCP value should be set in the packet, dscp
-     * will be set to DSCP_INVALID.  If no DSCP value is specified, DSCP_DEFAULT
-     * value will be applied.)
+     * packets it sends.
      *
      * Returns 0 if successful, otherwise a positive errno value.  If
      * successful, stores a pointer to the new connection in '*pstreamp'.

lib/unixctl.c

@@ -221,7 +221,7 @@ unixctl_server_create(const char *path, struct unixctl_server **serverp)
                                program_name, (long int) getpid());
     }
 
-    error = pstream_open(punix_path, &listener, DSCP_INVALID);
+    error = pstream_open(punix_path, &listener, 0);
     if (error) {
         ovs_error(error, "could not initialize control socket %s", punix_path);
         goto exit;

lib/vconn-provider.h

@@ -63,9 +63,7 @@ struct vconn_class {
      *
      * 'suffix' is a copy of 'name' following the colon and may be modified.
      * 'dscp' is the DSCP value that the new connection should use in the IP
-     * packets it sends.  (If no DSCP value should be set in the packet, dscp
-     * will be set to DSCP_INVALID.  If no DSCP value is specified, DSCP_DEFAULT
-     * value will be applied.)
+     * packets it sends.
      *
      * Returns 0 if successful, otherwise a positive errno value.  If
      * successful, stores a pointer to the new connection in '*vconnp'.
@@ -155,9 +153,7 @@ struct pvconn_class {
      *
      * 'suffix' is a copy of 'name' following the colon and may be modified.
      * 'dscp' is the DSCP value that the new connection should use in the IP
-     * packets it sends.  (If no DSCP value should be set in the packet, dscp
-     * will be set to DSCP_INVALID.  If no DSCP value is specified, DSCP_DEFAULT
-     * value will be applied.)
+     * packets it sends.
      *
      * Returns 0 if successful, otherwise a positive errno value.  If
      * successful, stores a pointer to the new connection in '*pvconnp'.

ofproto/collectors.c

@@ -63,8 +63,7 @@ collectors_create(const struct sset *targets, uint16_t default_port,
         int error;
         int fd;
 
-        error = inet_open_active(SOCK_DGRAM, name, default_port, NULL, &fd,
-                                 DSCP_INVALID);
+        error = inet_open_active(SOCK_DGRAM, name, default_port, NULL, &fd, 0);
         if (fd >= 0) {
             c->fds[c->n_fds++] = fd;
         } else {

ofproto/connmgr.c

@@ -674,7 +674,7 @@ set_pvconns(struct pvconn ***pvconnsp, size_t *n_pvconnsp,
         struct pvconn *pvconn;
         int error;
 
-        error = pvconn_open(name, &pvconn, DSCP_INVALID);
+        error = pvconn_open(name, &pvconn, 0);
         if (!error) {
             pvconns[n_pvconns++] = pvconn;
         } else {

tests/test-netflow.c

@@ -202,7 +202,7 @@ main(int argc, char *argv[])
     }
     target = argv[optind];
 
-    sock = inet_open_passive(SOCK_DGRAM, target, 0, NULL, DSCP_INVALID);
+    sock = inet_open_passive(SOCK_DGRAM, target, 0, NULL, 0);
     if (sock < 0) {
         ovs_fatal(0, "%s: failed to open (%s)", argv[1], strerror(-sock));
     }