Merge branch 'master' of https://github.com/getdnsapi/getdns

src/context.c

@@ -416,6 +416,7 @@ getdns_context_create_with_extended_memory_functions(
     if (!result) {
         return GETDNS_RETURN_GENERIC_ERROR;
     }
+    result->processing = 0;
     result->destroying = 0;
     result->my_mf.mf_arg         = userarg;
     result->my_mf.mf.ext.malloc  = malloc;
@@ -534,6 +535,12 @@ getdns_context_destroy(struct getdns_context *context)
     if (context == NULL) {
         return;
     }
+    // If being destroyed during getdns callback, just flag it
+    // and destroy.  See getdns_context_process_async
+    if (context->processing > 0) {
+        context->processing++;
+        return;
+    }
     context->destroying = 1;
     cancel_outstanding_requests(context, 1);
     getdns_extension_detach_eventloop(context);
@@ -1505,12 +1512,24 @@ getdns_context_get_num_pending_requests(struct getdns_context* context,
 /* process async reqs */
 getdns_return_t getdns_context_process_async(struct getdns_context* context) {
     RETURN_IF_NULL(context, GETDNS_RETURN_INVALID_PARAMETER);
+    context->processing = 1;
     if (ub_poll(context->unbound_ctx)) {
         if (ub_process(context->unbound_ctx) != 0) {
             /* need an async return code? */
             return GETDNS_RETURN_GENERIC_ERROR;
         }
     }
+    if (context->processing > 1) {
+        // destroyed during callbacks
+        // clear flag so destroy continues
+        context->processing = 0;
+        getdns_context_destroy(context);
+        // return bad context now that the context
+        // is destroyed
+        return GETDNS_RETURN_BAD_CONTEXT;
+    }
+    // reset the processing flag
+    context->processing = 0;
     if (context->extension != NULL) {
         /* no need to process timeouts since it is delegated
          * to the extension */

src/context.h

@@ -90,6 +90,7 @@ struct getdns_context {
 
 	getdns_update_callback update_callback;
 
+    int processing;
     int destroying;
 
 	struct mem_funcs mf;

src/extension/libev.c

@@ -59,7 +59,10 @@ request_count_changed(uint32_t request_count, struct getdns_libev_data *ev_data)
 static void
 getdns_libev_cb(struct ev_loop *loop, struct ev_io *handle, int revents) {
     struct getdns_context* context = (struct getdns_context*) handle->data;
-    getdns_context_process_async(context);
+    if (getdns_context_process_async(context) == GETDNS_RETURN_BAD_CONTEXT) {
+        // context destroyed
+        return;
+    }
     uint32_t rc = getdns_context_get_num_pending_requests(context, NULL);
     struct getdns_libev_data* ev_data =
         (struct getdns_libev_data*) getdns_context_get_extension_data(context);

src/extension/libevent.c

@@ -88,7 +88,10 @@ request_count_changed(uint32_t request_count, struct event_data *ev_data) {
 static void
 getdns_libevent_cb(evutil_socket_t fd, short what, void *userarg) {
     struct getdns_context* context = (struct getdns_context*) userarg;
-    getdns_context_process_async(context);
+    if (getdns_context_process_async(context) == GETDNS_RETURN_BAD_CONTEXT) {
+        // context destroyed
+        return;
+    }
     uint32_t rc = getdns_context_get_num_pending_requests(context, NULL);
     struct event_data* ev_data =
         (struct event_data*) getdns_context_get_extension_data(context);

src/extension/libuv.c

@@ -53,7 +53,10 @@ static void request_count_changed(uint32_t request_count, struct getdns_libuv_da
 static void
 getdns_libuv_cb(uv_poll_t* handle, int status, int events) {
     struct getdns_context* context = (struct getdns_context*) handle->data;
-    getdns_context_process_async(context);
+    if (getdns_context_process_async(context) == GETDNS_RETURN_BAD_CONTEXT) {
+        // context destroyed
+        return;
+    }
     uint32_t rc = getdns_context_get_num_pending_requests(context, NULL);
     struct getdns_libuv_data* uv_data =
         (struct getdns_libuv_data*) getdns_context_get_extension_data(context);

src/test/check_getdns_common.c

@@ -258,6 +258,17 @@ void assert_ptr_in_answer(struct extracted_response *ex_response)
   ck_assert_msg(ptr_records == 1, "Expected to find one PTR record in answer section, got %d", ptr_records);
 }
 
+void destroy_callbackfn(struct getdns_context *context,
+                        getdns_callback_type_t callback_type,
+                        struct getdns_dict *response,
+                        void *userarg,
+                        getdns_transaction_t transaction_id) {
+    int* flag = (int*)userarg;
+    *flag = 1;
+    getdns_dict_destroy(response);
+    getdns_context_destroy(context);
+}
+
 /*
  *  callbackfn is the callback function given to all
  *  asynchronous query tests.  It is expected to only

src/test/check_getdns_common.h

@@ -186,6 +186,12 @@
       */
      void assert_ptr_in_answer(struct extracted_response *ex_response);
 
+
+     void destroy_callbackfn(struct getdns_context *context,
+                     getdns_callback_type_t callback_type,
+                     struct getdns_dict *response,
+                     void *userarg,
+                     getdns_transaction_t transaction_id);
      /*
       *    callbackfn is the callback function given to all
       *    asynchronous query tests.  It is expected to only

src/test/check_getdns_context_destroy.h

@@ -177,6 +177,31 @@
      }
      END_TEST
 
+     START_TEST (getdns_context_destroy_7)
+     {
+      /*
+       *  destroy called immediately following getdns_address
+       *  expect: callback should be called before getdns_context_destroy() returns
+       */
+       struct getdns_context *context = NULL;
+       void* eventloop = NULL;
+       getdns_transaction_t transaction_id = 0;
+
+       int flag = 0;     /* Initialize flag */
+
+       CONTEXT_CREATE(TRUE);
+       EVENT_BASE_CREATE;
+
+       ASSERT_RC(getdns_address(context, "google.com", NULL,
+         &flag, &transaction_id, destroy_callbackfn),
+         GETDNS_RETURN_GOOD, "Return code from getdns_address()");
+
+       RUN_EVENT_LOOP;
+
+       ck_assert_msg(flag == 1, "flag should == 1, got %d", flag);
+     }
+     END_TEST
+
      void verify_getdns_context_destroy(struct extracted_response *ex_response)
      {
        /*
@@ -208,6 +233,7 @@
        tcase_add_test(tc_pos, getdns_context_destroy_4);
        tcase_add_test(tc_pos, getdns_context_destroy_5);
        tcase_add_test(tc_pos, getdns_context_destroy_6);
+       tcase_add_test(tc_pos, getdns_context_destroy_7);
        suite_add_tcase(s, tc_pos);
 
        return s;

src/test/check_getdns_selectloop.c

@@ -44,7 +44,10 @@ void run_event_loop_impl(struct getdns_context* context, void* eventloop) {
         FD_ZERO(&read_fds);
         FD_SET(fd, &read_fds);
         select(fd + 1, &read_fds, NULL, NULL, &tv);
-        getdns_context_process_async(context);
+        if (getdns_context_process_async(context) != GETDNS_RETURN_GOOD) {
+            // context destroyed
+            break;
+        }
     }
 }