Introduce strophe_free_and_null()

Signed-off-by: Steffen Jaeckel <jaeckel-floss@eyet-services.de>

Author: sjaeckel

src/common.h

@@ -93,6 +93,13 @@ void *strophe_realloc(const xmpp_ctx_t *ctx, void *p, size_t size);
 char *strophe_strdup(const xmpp_ctx_t *ctx, const char *s);
 char *strophe_strndup(const xmpp_ctx_t *ctx, const char *s, size_t len);
 void strophe_free(const xmpp_ctx_t *ctx, void *p);
+#define strophe_free_and_null(ctx, p) \
+    do {                              \
+        if (p) {                      \
+            strophe_free(ctx, (p));   \
+            (p) = NULL;               \
+        }                             \
+    } while (0)
 
 /* wrappers for xmpp_log at specific levels */
 void strophe_error(const xmpp_ctx_t *ctx,

src/conn.c

@@ -1804,21 +1804,13 @@ static void _conn_reset(xmpp_conn_t *conn)
 
     if (conn->stream_error) {
         xmpp_stanza_release(conn->stream_error->stanza);
-        if (conn->stream_error->text)
-            strophe_free(ctx, conn->stream_error->text);
-        strophe_free(ctx, conn->stream_error);
-        conn->stream_error = NULL;
+        strophe_free_and_null(ctx, conn->stream_error->text);
+        strophe_free_and_null(ctx, conn->stream_error);
     }
 
-    if (conn->domain)
-        strophe_free(ctx, conn->domain);
-    if (conn->bound_jid)
-        strophe_free(ctx, conn->bound_jid);
-    if (conn->stream_id)
-        strophe_free(ctx, conn->stream_id);
-    conn->domain = NULL;
-    conn->bound_jid = NULL;
-    conn->stream_id = NULL;
+    strophe_free_and_null(ctx, conn->domain);
+    strophe_free_and_null(ctx, conn->bound_jid);
+    strophe_free_and_null(ctx, conn->stream_id);
     conn->authenticated = 0;
     conn->secured = 0;
     conn->tls_failed = 0;