showmount command: move logic to acquire RPC client handle out of main()

In preparation to support IPv6 in the showmount command, extract the
logic that parses/acquires the target hostname and converts it into an RPC
client handle to contact the remote mountd service, and move it into its
own function.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Steve Dickson <steved@redhat.com>

diff --git a/utils/showmount/showmount.c b/utils/showmount/showmount.c
index 5951033373ca1273f399398535b7a1ac0f62190a..7f5ad3aa54fc79138f0c7cf92c0ea6d4c52fa72b 100644 (file)
--- a/utils/showmount/showmount.c
+++ b/utils/showmount/showmount.c
@@ -150,16 +150,75 @@ done:
        return ret;
 }
 
+/*
+ * Generate an RPC client handle connected to the mountd service
+ * at @hostname, or die trying.
+ *
+ * Supports only AF_INET server addresses.
+ */
+static CLIENT *nfs_get_mount_client(const char *hostname)
+{
+       struct hostent *hp;
+       struct sockaddr_in server_addr;
+       struct timeval pertry_timeout;
+       CLIENT *mclient = NULL;
+       int ret, msock;
+
+       if (inet_aton(hostname, &server_addr.sin_addr)) {
+               server_addr.sin_family = AF_INET;
+       }
+       else {
+               if ((hp = gethostbyname(hostname)) == NULL) {
+                       fprintf(stderr, "%s: can't get address for %s\n",
+                               program_name, hostname);
+                       exit(1);
+               }
+               server_addr.sin_family = AF_INET;
+               memcpy(&server_addr.sin_addr, hp->h_addr, hp->h_length);
+       }
+
+       msock = socket(PF_INET, SOCK_STREAM, IPPROTO_TCP);
+       if (msock != -1) {
+               if (nfs_getport_ping((struct sockaddr *)&server_addr,
+                                       sizeof(server_addr), MOUNTPROG,
+                                       MOUNTVERS, IPPROTO_TCP)) {
+                       ret = connect_nb(msock, &server_addr, 0);
+                       if (ret == 0)
+                               mclient = clnttcp_create(&server_addr,
+                                               MOUNTPROG, MOUNTVERS, &msock,
+                                               0, 0);
+                       else
+                               close(msock);
+               } else
+                       close(msock);
+       }
+
+       if (!mclient) {
+               if (nfs_getport_ping((struct sockaddr *)&server_addr,
+                                       sizeof(server_addr), MOUNTPROG,
+                                       MOUNTVERS, IPPROTO_UDP)) {
+                       clnt_pcreateerror("showmount");
+                       exit(1);
+               }
+               msock = RPC_ANYSOCK;
+               pertry_timeout.tv_sec = TIMEOUT_UDP;
+               pertry_timeout.tv_usec = 0;
+               if ((mclient = clntudp_create(&server_addr,
+                   MOUNTPROG, MOUNTVERS, pertry_timeout, &msock)) == NULL) {
+                       clnt_pcreateerror("mount clntudp_create");
+                       exit(1);
+               }
+       }
+
+       return mclient;
+}
+
 int main(int argc, char **argv)
 {
        char hostname_buf[MAXHOSTLEN];
        char *hostname;
        enum clnt_stat clnt_stat;
-       struct hostent *hp;
-       struct sockaddr_in server_addr;
-       int ret, msock;
        struct timeval total_timeout;
-       struct timeval pertry_timeout;
        int c;
        CLIENT *mclient;
        groups grouplist;
@@ -231,54 +290,7 @@ int main(int argc, char **argv)
                break;
        }
 
-       if (inet_aton(hostname, &server_addr.sin_addr)) {
-               server_addr.sin_family = AF_INET;
-       }
-       else {
-               if ((hp = gethostbyname(hostname)) == NULL) {
-                       fprintf(stderr, "%s: can't get address for %s\n",
-                               program_name, hostname);
-                       exit(1);
-               }
-               server_addr.sin_family = AF_INET;
-               memcpy(&server_addr.sin_addr, hp->h_addr, hp->h_length);
-       }
-
-       /* create mount deamon client */
-
-       mclient = NULL;
-       msock = socket(PF_INET, SOCK_STREAM, IPPROTO_TCP);
-       if (msock != -1) {
-               if (nfs_getport_ping((struct sockaddr *)&server_addr,
-                                       sizeof(server_addr), MOUNTPROG,
-                                       MOUNTVERS, IPPROTO_TCP)) {
-                       ret = connect_nb(msock, &server_addr, 0);
-                       if (ret == 0) /* success */
-                               mclient = clnttcp_create(&server_addr,
-                                               MOUNTPROG, MOUNTVERS, &msock,
-                                               0, 0);
-                       else
-                               close(msock);
-               } else
-                       close(msock);
-       }
-
-       if (!mclient) {
-               if (nfs_getport_ping((struct sockaddr *)&server_addr,
-                                       sizeof(server_addr), MOUNTPROG,
-                                       MOUNTVERS, IPPROTO_UDP)) {
-                       clnt_pcreateerror("showmount");
-                       exit(1);
-               }
-               msock = RPC_ANYSOCK;
-               pertry_timeout.tv_sec = TIMEOUT_UDP;
-               pertry_timeout.tv_usec = 0;
-               if ((mclient = clntudp_create(&server_addr,
-                   MOUNTPROG, MOUNTVERS, pertry_timeout, &msock)) == NULL) {
-                       clnt_pcreateerror("mount clntudp_create");
-                       exit(1);
-               }
-       }
+       mclient = nfs_get_mount_client(hostname);
        mclient->cl_auth = authunix_create_default();
        total_timeout.tv_sec = TOTAL_TIMEOUT;
        total_timeout.tv_usec = 0;