X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=blobdiff_plain;f=net.c;h=463033bb710a36036ca37907ecc59016fd6dd304;hp=7a987444114abf7890251bb10da7e82507b87b64;hb=fdbdd1fd575d7d37d4fb182252107a4d3816853c;hpb=0c4bb93fbfc543cf2c5ff2acb6a7f7a824163b57

diff --git a/net.c b/net.c
index 7a987444..463033bb 100644
--- a/net.c
+++ b/net.c
@@ -622,11 +622,9 @@ int generic_max_transport_msg_size(int sockfd)
 }
 
 /**
- * Look up the local or remote side of a connected socket structure.
+ * Look up the remote side of a connected socket structure.
  *
  * \param fd The socket descriptor of the connected socket.
- * \param getname Either \p getsockname() for local, or \p getpeername() for
- * remote side.
  *
  * \return A static character string identifying hostname and port of the
  * chosen side in numeric host:port format.
@@ -634,7 +632,7 @@ int generic_max_transport_msg_size(int sockfd)
  * \sa getsockname(2), getpeername(2), parse_url(), getnameinfo(3),
  * services(5), nsswitch.conf(5).
  */
-static char *__get_sock_name(int fd, typeof(getsockname) getname)
+char *remote_name(int fd)
 {
 	struct sockaddr_storage ss;
 	const struct sockaddr *sa;
@@ -643,7 +641,7 @@ static char *__get_sock_name(int fd, typeof(getsockname) getname)
 	static char output[sizeof(hbuf) + sizeof(sbuf) + 4];
 	int ret;
 
-	if (getname(fd, (struct sockaddr *)&ss, &sslen) < 0) {
+	if (getpeername(fd, (struct sockaddr *)&ss, &sslen) < 0) {
 		PARA_ERROR_LOG("can not determine address from fd %d: %s\n",
 			fd, strerror(errno));
 		snprintf(output, sizeof(output), "(unknown)");
@@ -663,19 +661,6 @@ static char *__get_sock_name(int fd, typeof(getsockname) getname)
 	return output;
 }
 
-/**
- * Look up the remote side of a connected socket structure.
- *
- * \param sockfd The file descriptor of the socket.
- *
- * \return A pointer to a static buffer containing hostname an port. This
- * buffer must not be freed by the caller.
- */
-char *remote_name(int sockfd)
-{
-	return __get_sock_name(sockfd, getpeername);
-}
-
 /**
  * Extract IPv4 or IPv6-mapped-IPv4 address from sockaddr_storage.
  *
@@ -849,51 +834,66 @@ int dccp_available_ccids(uint8_t **ccid_array)
  * \return Positive on success, \p -E_NAME_TOO_LONG if \a name is longer
  * than \p UNIX_PATH_MAX.
  */
-static int init_unix_addr(struct sockaddr_un *u, const char *name)
+static int init_unix_addr(struct sockaddr_un *u, const char *name,
+		bool abstract)
 {
-	if (strlen(name) >= UNIX_PATH_MAX)
+	if (strlen(name) + abstract >= UNIX_PATH_MAX)
 		return -E_NAME_TOO_LONG;
 	memset(u->sun_path, 0, UNIX_PATH_MAX);
 	u->sun_family = PF_UNIX;
-	strcpy(u->sun_path, name);
+	strcpy(u->sun_path + abstract, name);
 	return 1;
 }
 
 /**
- * Prepare, create, and bind a socket for local communication.
+ * Create a socket for local communication and listen on it.
  *
  * \param name The socket pathname.
  * \param mode The desired permissions of the socket.
  *
- * This function creates a local socket for sequenced, reliable,
- * two-way, connection-based byte streams.
+ * This function creates a passive local socket for sequenced, reliable,
+ * two-way, connection-based byte streams. The socket file descriptor is set to
+ * nonblocking mode and listen(2) is called to prepare the socket for
+ * accepting incoming connection requests.
+ *
+ * If mode is zero, an abstract socket (a non-portable Linux extension) is
+ * created. In this case the socket name has no connection with filesystem
+ * pathnames.
  *
- * \return The file descriptor, on success, negative on errors.
+ * \return The file descriptor on success, negative error code on failure.
  *
- * \sa socket(2)
- * \sa bind(2)
- * \sa chmod(2)
+ * \sa socket(2), \sa bind(2), \sa chmod(2), listen(2), unix(7).
  */
 int create_local_socket(const char *name, mode_t mode)
 {
 	struct sockaddr_un unix_addr;
 	int fd, ret;
+	bool abstract = mode == 0;
 
-	ret = init_unix_addr(&unix_addr, name);
+	ret = init_unix_addr(&unix_addr, name, abstract);
 	if (ret < 0)
 		return ret;
 	ret = socket(PF_UNIX, SOCK_STREAM, 0);
 	if (ret < 0)
 		return -ERRNO_TO_PARA_ERROR(errno);
 	fd = ret;
-	ret = bind(fd, (struct sockaddr *)&unix_addr, UNIX_PATH_MAX);
+	ret = mark_fd_nonblocking(fd);
+	if (ret < 0)
+		goto err;
+	ret = bind(fd, (struct sockaddr *)&unix_addr, sizeof(unix_addr));
 	if (ret < 0) {
 		ret = -ERRNO_TO_PARA_ERROR(errno);
 		goto err;
 	}
-	ret = -E_CHMOD;
-	if (chmod(name, mode) < 0)
+	if (!abstract) {
+		ret = -E_CHMOD;
+		if (chmod(name, mode) < 0)
+			goto err;
+	}
+	if (listen(fd , 5) < 0) {
+		ret = -ERRNO_TO_PARA_ERROR(errno);
 		goto err;
+	}
 	return fd;
 err:
 	close(fd);
@@ -919,17 +919,22 @@ int connect_local_socket(const char *name)
 	int fd, ret;
 
 	PARA_DEBUG_LOG("connecting to %s\n", name);
-	ret = init_unix_addr(&unix_addr, name);
-	if (ret < 0)
-		return ret;
 	fd = socket(PF_UNIX, SOCK_STREAM, 0);
 	if (fd < 0)
 		return -ERRNO_TO_PARA_ERROR(errno);
-	if (connect(fd, (struct sockaddr *)&unix_addr, sizeof(unix_addr)) == -1) {
-		ret = -ERRNO_TO_PARA_ERROR(errno);
+	/* first try (linux-only) abstract socket */
+	ret = init_unix_addr(&unix_addr, name, true);
+	if (ret < 0)
 		goto err;
-	}
-	return fd;
+	if (connect(fd, (struct sockaddr *)&unix_addr, sizeof(unix_addr)) != -1)
+		return fd;
+	/* next try pathname socket */
+	ret = init_unix_addr(&unix_addr, name, false);
+	if (ret < 0)
+		goto err;
+	if (connect(fd, (struct sockaddr *)&unix_addr, sizeof(unix_addr)) != -1)
+		return fd;
+	ret = -ERRNO_TO_PARA_ERROR(errno);
 err:
 	close(fd);
 	return ret;