conn: xmpp_conn_set_keepalive() stores parameters in conn

Store keepalive parameters in conn object. This allows call the function
with a disconnected conn. Also, the parameters are not cleared on
reconnect and applied once a socket is created.

examples/basic.c

@@ -14,6 +14,9 @@
 
 #include <strophe.h>
 
+/* hardcoded TCP keepalive timeout and interval */
+#define KA_TIMEOUT 60
+#define KA_INTERVAL 1
 
 /* define a handler for connection events */
 void conn_handler(xmpp_conn_t * const conn, const xmpp_conn_event_t status,
@@ -43,6 +46,7 @@ int main(int argc, char **argv)
     xmpp_log_t *log;
     char *jid, *pass, *host = NULL;
     long flags = 0;
+    int tcp_keepalive = 0;
     int i;
 
     /* take a jid and password on the command line */
@@ -53,6 +57,8 @@ int main(int argc, char **argv)
             flags |= XMPP_CONN_FLAG_MANDATORY_TLS;
         else if (strcmp(argv[i], "--legacy-ssl") == 0)
             flags |= XMPP_CONN_FLAG_LEGACY_SSL;
+        else if (strcmp(argv[i], "--tcp-keepalive") == 0)
+            tcp_keepalive = 1;
         else
             break;
     }
@@ -61,7 +67,8 @@ int main(int argc, char **argv)
                         "Options:\n"
                         "  --disable-tls        Disable TLS.\n"
                         "  --mandatory-tls      Deny plaintext connection.\n"
-                        "  --legacy-ssl         Use old style SSL.\n\n"
+                        "  --legacy-ssl         Use old style SSL.\n"
+                        "  --tcp-keepalive      Configure TCP keepalive.\n\n"
                         "Note: --disable-tls conflicts with --mandatory-tls or "
                               "--legacy-ssl\n");
         return 1;
@@ -89,6 +96,8 @@ int main(int argc, char **argv)
 
     /* configure connection properties (optional) */
     xmpp_conn_set_flags(conn, flags);
+    /* configure TCP keepalive (optional) */
+    if (tcp_keepalive) xmpp_conn_set_keepalive(conn, KA_TIMEOUT, KA_INTERVAL);
 
     /* setup authentication information */
     xmpp_conn_set_jid(conn, jid);

src/common.h

@@ -155,9 +155,12 @@ struct _xmpp_conn_t {
     uint64_t timeout_stamp;
     int error;
     xmpp_stream_error_t *stream_error;
-    sock_t sock;
-    tls_t *tls;
 
+    sock_t sock;
+    int ka_timeout; /* TCP keepalive timeout */
+    int ka_interval; /* TCP keepalive interval */
+
+    tls_t *tls;
     int tls_support;
     int tls_disabled;
     int tls_mandatory;

src/conn.c

@@ -90,6 +90,8 @@ xmpp_conn_t *xmpp_conn_new(xmpp_ctx_t * const ctx)
         conn->type = XMPP_UNKNOWN;
         conn->state = XMPP_STATE_DISCONNECTED;
         conn->sock = -1;
+        conn->ka_timeout = 0;
+        conn->ka_interval = 0;
         conn->tls = NULL;
         conn->timeout_stamp = 0;
         conn->error = 0;
@@ -185,7 +187,9 @@ xmpp_conn_t *xmpp_conn_clone(xmpp_conn_t * const conn)
 
 /** Set TCP keepalive parameters
  *  Turn on TCP keepalive and set timeout and interval. Zero timeout
- *  disables TCP keepalives.
+ *  disables TCP keepalives. The parameters are applied immediately for
+ *  a non disconnected object. Also, they are applied when the connection
+ *  object connects successfully.
  *
  *  @param conn a Strophe connection object
  *  @param timeout TCP keepalive timeout in seconds
@@ -195,14 +199,14 @@ xmpp_conn_t *xmpp_conn_clone(xmpp_conn_t * const conn)
  */
 void xmpp_conn_set_keepalive(xmpp_conn_t * const conn, int timeout, int interval)
 {
-    int ret;
+    int ret = 0;
+
+    conn->ka_timeout = timeout;
+    conn->ka_interval = interval;
+
+    if (conn->state != XMPP_STATE_DISCONNECTED)
+        ret = sock_set_keepalive(conn->sock, timeout, interval);
 
-    if (conn->state == XMPP_STATE_DISCONNECTED) {
-        xmpp_error(conn->ctx, "xmpp", "Setting TCP keepalive impossible on"
-                                      "disconnected connection");
-        return;
-    }
-    ret = sock_set_keepalive(conn->sock, timeout, interval);
     if (ret < 0) {
         xmpp_error(conn->ctx, "xmpp", "Setting TCP keepalive (%d,%d) error: %d",
                    timeout, interval, sock_error());
@@ -1003,7 +1007,6 @@ static int _conn_connect(xmpp_conn_t * const conn,
                          xmpp_conn_handler callback,
                          void * const userdata)
 {
-
     if (conn->state != XMPP_STATE_DISCONNECTED) return -1;
     if (type != XMPP_CLIENT && type != XMPP_COMPONENT) return -1;
 
@@ -1017,6 +1020,8 @@ static int _conn_connect(xmpp_conn_t * const conn,
     xmpp_debug(conn->ctx, "xmpp", "sock_connect() to %s:%u returned %d",
                host, port, conn->sock);
     if (conn->sock == -1) return -1;
+    if (conn->ka_timeout || conn->ka_interval)
+        sock_set_keepalive(conn->sock, conn->ka_timeout, conn->ka_interval);
 
     /* setup handler */
     conn->conn_handler = callback;