imap-send: add support for IPv6

Add IPv6 support by implementing name resolution with the
protocol agnostic getaddrinfo(3) API. The old gethostbyname(3)
code is still available when git is compiled with NO_IPV6.

Signed-off-by: Benjamin Kramer <benny.kra@googlemail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/imap-send.c b/imap-send.c
index 8154cb2116da9257ecf286c46f77fc1ed2a62afc..e4c83b9d5b989671c1accc573235479ad77a5ab7 100644 (file)
--- a/imap-send.c
+++ b/imap-send.c
@@ -982,9 +982,7 @@ static struct store *imap_open_store(struct imap_server_conf *srvc)
        struct imap_store *ctx;
        struct imap *imap;
        char *arg, *rsp;
-       struct hostent *he;
-       struct sockaddr_in addr;
-       int s, a[2], preauth;
+       int s = -1, a[2], preauth;
        pid_t pid;
 
        ctx = xcalloc(sizeof(*ctx), 1);
@@ -1021,6 +1019,51 @@ static struct store *imap_open_store(struct imap_server_conf *srvc)
 
                imap_info("ok\n");
        } else {
+#ifndef NO_IPV6
+               struct addrinfo hints, *ai0, *ai;
+               int gai;
+               char portstr[6];
+
+               snprintf(portstr, sizeof(portstr), "%hu", srvc->port);
+
+               memset(&hints, 0, sizeof(hints));
+               hints.ai_socktype = SOCK_STREAM;
+               hints.ai_protocol = IPPROTO_TCP;
+
+               imap_info("Resolving %s... ", srvc->host);
+               gai = getaddrinfo(srvc->host, portstr, &hints, &ai);
+               if (gai) {
+                       fprintf(stderr, "getaddrinfo: %s\n", gai_strerror(gai));
+                       goto bail;
+               }
+               imap_info("ok\n");
+
+               for (ai0 = ai; ai; ai = ai->ai_next) {
+                       char addr[NI_MAXHOST];
+
+                       s = socket(ai->ai_family, ai->ai_socktype,
+                                  ai->ai_protocol);
+                       if (s < 0)
+                               continue;
+
+                       getnameinfo(ai->ai_addr, ai->ai_addrlen, addr,
+                                   sizeof(addr), NULL, 0, NI_NUMERICHOST);
+                       imap_info("Connecting to [%s]:%s... ", addr, portstr);
+
+                       if (connect(s, ai->ai_addr, ai->ai_addrlen) < 0) {
+                               close(s);
+                               s = -1;
+                               perror("connect");
+                               continue;
+                       }
+
+                       break;
+               }
+               freeaddrinfo(ai0);
+#else /* NO_IPV6 */
+               struct hostent *he;
+               struct sockaddr_in addr;
+
                memset(&addr, 0, sizeof(addr));
                addr.sin_port = htons(srvc->port);
                addr.sin_family = AF_INET;
@@ -1040,7 +1083,12 @@ static struct store *imap_open_store(struct imap_server_conf *srvc)
                imap_info("Connecting to %s:%hu... ", inet_ntoa(addr.sin_addr), ntohs(addr.sin_port));
                if (connect(s, (struct sockaddr *)&addr, sizeof(addr))) {
                        close(s);
+                       s = -1;
                        perror("connect");
+               }
+#endif
+               if (s < 0) {
+                       fputs("Error: unable to connect to server.\n", stderr);
                        goto bail;
                }