Added way to remove filters from channel stack builder
diff --git a/test/core/channel/channel_stack_builder_test.c b/test/core/channel/channel_stack_builder_test.c
new file mode 100644
index 0000000..be6afb7
--- /dev/null
+++ b/test/core/channel/channel_stack_builder_test.c
@@ -0,0 +1,152 @@
+/*
+ *
+ * Copyright 2017 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+#include "src/core/lib/channel/channel_stack_builder.h"
+
+#include <limits.h>
+#include <string.h>
+
+#include <grpc/support/alloc.h>
+#include <grpc/support/log.h>
+#include <grpc/support/string_util.h>
+
+#include "src/core/lib/slice/slice_internal.h"
+#include "src/core/lib/surface/channel_init.h"
+#include "test/core/util/test_config.h"
+
+static grpc_error *channel_init_func(grpc_exec_ctx *exec_ctx,
+ grpc_channel_element *elem,
+ grpc_channel_element_args *args) {
+ return GRPC_ERROR_NONE;
+}
+
+static grpc_error *call_init_func(grpc_exec_ctx *exec_ctx,
+ grpc_call_element *elem,
+ const grpc_call_element_args *args) {
+ return GRPC_ERROR_NONE;
+}
+
+static void channel_destroy_func(grpc_exec_ctx *exec_ctx,
+ grpc_channel_element *elem) {}
+
+static void call_destroy_func(grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
+ const grpc_call_final_info *final_info,
+ grpc_closure *ignored) {}
+
+static void call_func(grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
+ grpc_transport_stream_op_batch *op) {}
+
+static void channel_func(grpc_exec_ctx *exec_ctx, grpc_channel_element *elem,
+ grpc_transport_op *op) {
+ if (op->disconnect_with_error != GRPC_ERROR_NONE) {
+ GRPC_ERROR_UNREF(op->disconnect_with_error);
+ }
+ GRPC_CLOSURE_SCHED(exec_ctx, op->on_consumed, GRPC_ERROR_NONE);
+}
+
+static char *get_peer(grpc_exec_ctx *exec_ctx, grpc_call_element *elem) {
+ return gpr_strdup("peer");
+}
+
+bool g_replacement_fn_called = false;
+bool g_original_fn_called = false;
+void set_arg_once_fn(grpc_channel_stack *channel_stack,
+ grpc_channel_element *elem, void *arg) {
+ bool *called = arg;
+ // Make sure this function is only called once per arg.
+ GPR_ASSERT(*called == false);
+ *called = true;
+}
+
+static void test_channel_stack_builder_filter_replace(void) {
+ grpc_channel *channel =
+ grpc_insecure_channel_create("target name isn't used", NULL, NULL);
+ GPR_ASSERT(channel != NULL);
+ // Make sure the high priority filter has been created.
+ GPR_ASSERT(g_replacement_fn_called);
+ // ... and that the low priority one hasn't.
+ GPR_ASSERT(!g_original_fn_called);
+ grpc_channel_destroy(channel);
+}
+
+const grpc_channel_filter replacement_filter = {
+ call_func,
+ channel_func,
+ 0,
+ call_init_func,
+ grpc_call_stack_ignore_set_pollset_or_pollset_set,
+ call_destroy_func,
+ 0,
+ channel_init_func,
+ channel_destroy_func,
+ get_peer,
+ grpc_channel_next_get_info,
+ "filter_name"};
+
+const grpc_channel_filter original_filter = {
+ call_func,
+ channel_func,
+ 0,
+ call_init_func,
+ grpc_call_stack_ignore_set_pollset_or_pollset_set,
+ call_destroy_func,
+ 0,
+ channel_init_func,
+ channel_destroy_func,
+ get_peer,
+ grpc_channel_next_get_info,
+ "filter_name"};
+
+static bool add_replacement_filter(grpc_exec_ctx *exec_ctx,
+ grpc_channel_stack_builder *builder,
+ void *arg) {
+ const grpc_channel_filter *filter = arg;
+ // Get rid of any other version of the filter, as determined by having the
+ // same name.
+ GPR_ASSERT(grpc_channel_stack_builder_remove_filter(builder, filter->name));
+ return grpc_channel_stack_builder_prepend_filter(
+ builder, filter, set_arg_once_fn, &g_replacement_fn_called);
+}
+
+static bool add_original_filter(grpc_exec_ctx *exec_ctx,
+ grpc_channel_stack_builder *builder,
+ void *arg) {
+ return grpc_channel_stack_builder_prepend_filter(
+ builder, (const grpc_channel_filter *)arg, set_arg_once_fn,
+ &g_original_fn_called);
+}
+
+static void init_plugin(void) {
+ grpc_channel_init_register_stage(GRPC_CLIENT_CHANNEL, INT_MAX,
+ add_original_filter,
+ (void *)&original_filter);
+ grpc_channel_init_register_stage(GRPC_CLIENT_CHANNEL, INT_MAX,
+ add_replacement_filter,
+ (void *)&replacement_filter);
+}
+
+static void destroy_plugin(void) {}
+
+int main(int argc, char **argv) {
+ grpc_test_init(argc, argv);
+ grpc_register_plugin(init_plugin, destroy_plugin);
+ grpc_init();
+ test_channel_stack_builder_filter_replace();
+ grpc_shutdown();
+ return 0;
+}