- Updated the comments for open_socket_in().

- Changed open_socket_in() to return an array of ints with a trailing -1
  value to indicate the end of the list.
- Use the out_of_memory() routine to complain about no memory.
- Undid the recent IPV6_V6ONLY change, as I think it would prevent the
  use of IPv6 sockets on some older systems.
- If we get an EADDRINUSE error and this is not the first socket in the
  list, suggest that the user try --ipv4 or --ipv6.
- When forking, the child now closes all the open bound sockets, not just
  one of them (I'm not talking about the fd from accept(), obviously).

diff --git a/socket.c b/socket.c
index 93f05a9..0f47391 100644 (file)
--- a/socket.c
+++ b/socket.c
@@ -33,6 +33,8 @@
 
 #include "rsync.h"
 
+extern char *bind_address;
+extern int default_af_hint;
 
 /**
  * Establish a proxy connection on an open socket to a web proxy by
@@ -314,15 +316,14 @@ int open_socket_out_wrapped(char *host, int port, const char *bind_address,
 
 
 /**
- * Open a socket of the specified type, port and address for incoming data
+ * Open one or more sockets for incoming data using the specified type,
+ * port, and address.
  *
- * Try to be better about handling the results of getaddrinfo(): when
- * opening an inbound socket, we might get several address results,
- * e.g. for the machine's IPv4 and IPv6 name.
+ * The getaddrinfo() call may return several address results, e.g. for
+ * the machine's IPv4 and IPv6 name.
  *
- * We return an array of socket file-descriptors, with the length of
- * the array stored as the first element of the list.  This allows
- * the caller to listen on all of them.
+ * We return an array of file-descriptors to the sockets, with a trailing
+ * -1 value to indicate the end of the list.
  *
  * @param bind_address Local address to bind, or NULL to allow it to
  * default.
@@ -330,8 +331,8 @@ int open_socket_out_wrapped(char *host, int port, const char *bind_address,
 static int *open_socket_in(int type, int port, const char *bind_address,
                           int af_hint)
 {
-       int one=1;
-       int s, *sp, *socks, maxs;
+       int one = 1;
+       int s, *socks, maxs, i;
        struct addrinfo hints, *all_ai, *resp;
        char portbuf[10];
        int error;
@@ -350,18 +351,14 @@ static int *open_socket_in(int type, int port, const char *bind_address,
 
        /* Count max number of sockets we might open. */
        for (maxs = 0, resp = all_ai; resp; resp = resp->ai_next, maxs++) {}
-       socks = new_array(int, maxs + 1);
-       if (!socks) {
-               rprintf(FERROR,
-                       RSYNC_NAME "couldn't allocate memory for sockets");
-               return NULL;
-       }
+
+       if (!(socks = new_array(int, maxs + 1)))
+               out_of_memory("open_socket_in");
 
        /* We may not be able to create the socket, if for example the
         * machine knows about IPv6 in the C library, but not in the
         * kernel. */
-       sp = socks + 1; /* Leave room for count at start of array. */
-       for (resp = all_ai; resp; resp = resp->ai_next) {
+       for (resp = all_ai, i = 0; resp; resp = resp->ai_next) {
                s = socket(resp->ai_family, resp->ai_socktype,
                           resp->ai_protocol);
 
@@ -375,11 +372,8 @@ static int *open_socket_in(int type, int port, const char *bind_address,
 
 #ifdef IPV6_V6ONLY
                if (resp->ai_family == AF_INET6) {
-                       if (setsockopt(s, IPPROTO_IPV6, IPV6_V6ONLY,
-                                      (char *)&one, sizeof one) < 0) {
-                               close(s);
-                               continue;
-                       }
+                       setsockopt(s, IPPROTO_IPV6, IPV6_V6ONLY,
+                                  (char *)&one, sizeof one) < 0;
                }
 #endif
 
@@ -390,17 +384,17 @@ static int *open_socket_in(int type, int port, const char *bind_address,
                        continue;
                }
 
-               *sp++ = s;
+               socks[i++] = s;
        }
-       *socks = sp - socks - 1;   /* Save count. */
+       socks[i] = -1;
 
        if (all_ai)
                freeaddrinfo(all_ai);
 
-       if (*socks == 0) {
+       if (!i) {
                rprintf(FERROR,
-                       RSYNC_NAME ": open inbound socket on port %d failed: "
-                       "%s\n", port, strerror(errno));
+                       "unable to bind any inbound sockets on port %d\n",
+                       port);
                free(socks);
                return NULL;
        }
@@ -446,8 +440,6 @@ void start_accept_loop(int port, int (*fn)(int, int))
 {
        fd_set deffds;
        int *sp, maxfd, i;
-       extern char *bind_address;
-       extern int default_af_hint;
 
        /* open an incoming socket */
        sp = open_socket_in(SOCK_STREAM, port, bind_address, default_af_hint);
@@ -456,9 +448,16 @@ void start_accept_loop(int port, int (*fn)(int, int))
 
        /* ready to listen */
        FD_ZERO(&deffds);
-       maxfd = -1;
-       for (i = 1; i <= *sp; i++) {
-               if (listen(sp[i], 5) == -1) {
+       for (i = 0, maxfd = -1; sp[i] >= 0; i++) {
+               if (listen(sp[i], 5) < 0) {
+                       rprintf(FERROR, "listen() on socket failed: %s\n",
+                               strerror(errno));
+#ifdef INET6
+                       if (errno == EADDRINUSE && i > 0) {
+                               rprintf(FINFO,
+                                   "Try using --ipv4 or --ipv6 to avoid this listen() error.");
+                       }
+#endif
                        exit_cleanup(RERR_SOCKETIO);
                }
                FD_SET(sp[i], &deffds);
@@ -490,8 +489,7 @@ void start_accept_loop(int port, int (*fn)(int, int))
                if (select(maxfd + 1, &fds, NULL, NULL, NULL) != 1)
                        continue;
 
-               fd = -1;
-               for (i = 1; i <= *sp; i++) {
+               for (i = 0, fd = -1; sp[i] >= 0; i++) {
                        if (FD_ISSET(sp[i], &fds)) {
                                fd = accept(sp[i], (struct sockaddr *)&addr,
                                            &addrlen);
@@ -506,7 +504,8 @@ void start_accept_loop(int port, int (*fn)(int, int))
 
                if ((pid = fork()) == 0) {
                        int ret;
-                       close(sp[i]);
+                       for (i = 0; sp[i] >= 0; i++)
+                               close(sp[i]);
                        /* open log file in child before possibly giving
                         * up privileges  */
                        log_open();