X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=lib%2Fsocket-util.c;h=e400bb543abc1cdbf34919aa84e9d111083c0849;hb=6d65eee8b1f4d96b9c925d3b31758268345a4636;hp=e5b86e42773a4105c9cac09a1b5b99523ff5124c;hpb=e3fdfed11b8c56aa6a8deffe11a552fed7e7adbc;p=openvswitch

diff --git a/lib/socket-util.c b/lib/socket-util.c
index e5b86e42..e400bb54 100644
--- a/lib/socket-util.c
+++ b/lib/socket-util.c
@@ -73,25 +73,16 @@ get_max_fds(void)
     return max_fds;
 }
 
-/* Translates 'host_name', which may be a DNS name or an IP address, into a
- * numeric IP address in '*addr'.  Returns 0 if successful, otherwise a
- * positive errno value. */
+/* Translates 'host_name', which must be a string representation of an IP
+ * address, into a numeric IP address in '*addr'.  Returns 0 if successful,
+ * otherwise a positive errno value. */
 int
 lookup_ip(const char *host_name, struct in_addr *addr) 
 {
     if (!inet_aton(host_name, addr)) {
-        struct hostent *he = gethostbyname(host_name);
-        if (he == NULL) {
-            struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(1, 5);
-            VLOG_ERR_RL(&rl, "gethostbyname(%s): %s", host_name,
-                        (h_errno == HOST_NOT_FOUND ? "host not found"
-                         : h_errno == TRY_AGAIN ? "try again"
-                         : h_errno == NO_RECOVERY ? "non-recoverable error"
-                         : h_errno == NO_ADDRESS ? "no address"
-                         : "unknown error"));
-            return ENOENT;
-        }
-        addr->s_addr = *(uint32_t *) he->h_addr;
+        struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(1, 5);
+        VLOG_ERR_RL(&rl, "\"%s\" is not a valid IP address", host_name);
+        return ENOENT;
     }
     return 0;
 }
@@ -301,8 +292,9 @@ guess_netmask(uint32_t ip)
 }
 
 /* Opens a non-blocking TCP socket and connects to 'target', which should be a
- * string in the format "<host>[:<port>]", where <host> is required and <port>
- * is optional, with 'default_port' assumed if <port> is omitted.
+ * string in the format "<host>[:<port>]".  <host> is required.  If
+ * 'default_port' is nonzero then <port> is optional and defaults to
+ * 'default_port'.
  *
  * On success, returns 0 (indicating connection complete) or EAGAIN (indicating
  * connection in progress), in which case the new file descriptor is stored
@@ -344,6 +336,10 @@ tcp_open_active(const char *target_, uint16_t default_port,
     }
     if (port_string && atoi(port_string)) {
         sin.sin_port = htons(atoi(port_string));
+    } else if (!default_port) {
+        VLOG_ERR("%s: port number must be specified", target_);
+        error = EAFNOSUPPORT;
+        goto exit;
     }
 
     /* Create non-blocking socket. */
@@ -385,10 +381,10 @@ exit:
 }
 
 /* Opens a non-blocking TCP socket, binds to 'target', and listens for incoming
- * connections.  'target' should be a string in the format "[<port>][:<ip>]",
- * where both <port> and <ip> are optional.  If <port> is omitted, it defaults
- * to 'default_port'; if <ip> is omitted it defaults to the wildcard IP
- * address.
+ * connections.  'target' should be a string in the format "[<port>][:<ip>]".
+ * <port> may be omitted if 'default_port' is nonzero, in which case it
+ * defaults to 'default_port'.  If <ip> is omitted it defaults to the wildcard
+ * IP address.
  *
  * The socket will have SO_REUSEADDR turned on.
  *
@@ -415,6 +411,10 @@ tcp_open_passive(const char *target_, uint16_t default_port)
     port_string = strsep(&string_ptr, ":");
     if (port_string && atoi(port_string)) {
         sin.sin_port = htons(atoi(port_string));
+    } else if (!default_port) {
+        VLOG_ERR("%s: port number must be specified", target_);
+        error = EAFNOSUPPORT;
+        goto exit;
     }
 
     /* Parse optional bind IP. */
@@ -466,6 +466,24 @@ exit:
     return error ? -error : fd;
 }
 
+/* Returns a readable and writable fd for /dev/null, if successful, otherwise
+ * a negative errno value.  The caller must not close the returned fd (because
+ * the same fd will be handed out to subsequent callers). */
+int
+get_null_fd(void)
+{
+    static int null_fd = -1;
+    if (null_fd < 0) {
+        null_fd = open("/dev/null", O_RDWR);
+        if (null_fd < 0) {
+            int error = errno;
+            VLOG_ERR("could not open /dev/null: %s", strerror(error));
+            return -error;
+        }
+    }
+    return null_fd;
+}
+
 int
 read_fully(int fd, void *p_, size_t size, size_t *bytes_read)
 {