1 files changed, 104 insertions, 0 deletions
diff --git a/src/core/ext/filters/load_reporting/load_reporting.c b/src/core/ext/filters/load_reporting/load_reporting.c
new file mode 100644
index 0000000000..9fb33bab71
--- /dev/null
+++ b/src/core/ext/filters/load_reporting/load_reporting.c
@@ -0,0 +1,104 @@
+/*
+ *
+ * Copyright 2016, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+#include <limits.h>
+#include <string.h>
+
+#include <grpc/load_reporting.h>
+#include <grpc/support/alloc.h>
+#include <grpc/support/sync.h>
+
+#include "src/core/ext/filters/load_reporting/load_reporting.h"
+#include "src/core/ext/filters/load_reporting/load_reporting_filter.h"
+#include "src/core/lib/channel/channel_stack_builder.h"
+#include "src/core/lib/slice/slice_internal.h"
+#include "src/core/lib/surface/call.h"
+#include "src/core/lib/surface/channel_init.h"
+
+static void destroy_lr_cost_context(void *c) {
+  grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
+  grpc_load_reporting_cost_context *cost_ctx = c;
+  for (size_t i = 0; i < cost_ctx->values_count; ++i) {
+    grpc_slice_unref_internal(&exec_ctx, cost_ctx->values[i]);
+  }
+  grpc_exec_ctx_finish(&exec_ctx);
+  gpr_free(cost_ctx->values);
+  gpr_free(cost_ctx);
+}
+
+void grpc_call_set_load_reporting_cost_context(
+    grpc_call *call, grpc_load_reporting_cost_context *ctx) {
+  grpc_call_context_set(call, GRPC_CONTEXT_LR_COST, ctx,
+                        destroy_lr_cost_context);
+}
+
+static bool is_load_reporting_enabled(const grpc_channel_args *a) {
+  if (a == NULL) return false;
+  for (size_t i = 0; i < a->num_args; i++) {
+    if (0 == strcmp(a->args[i].key, GRPC_ARG_ENABLE_LOAD_REPORTING)) {
+      return a->args[i].type == GRPC_ARG_INTEGER &&
+             a->args[i].value.integer != 0;
+    }
+  }
+  return false;
+}
+
+static bool maybe_add_load_reporting_filter(grpc_exec_ctx *exec_ctx,
+                                            grpc_channel_stack_builder *builder,
+                                            void *arg) {
+  const grpc_channel_args *args =
+      grpc_channel_stack_builder_get_channel_arguments(builder);
+  if (is_load_reporting_enabled(args)) {
+    return grpc_channel_stack_builder_prepend_filter(
+        builder, (const grpc_channel_filter *)arg, NULL, NULL);
+  }
+  return true;
+}
+
+grpc_arg grpc_load_reporting_enable_arg() {
+  grpc_arg arg;
+  arg.type = GRPC_ARG_INTEGER;
+  arg.key = GRPC_ARG_ENABLE_LOAD_REPORTING;
+  arg.value.integer = 1;
+  return arg;
+}
+
+/* Plugin registration */
+
+void grpc_load_reporting_plugin_init(void) {
+  grpc_channel_init_register_stage(GRPC_SERVER_CHANNEL, INT_MAX,
+                                   maybe_add_load_reporting_filter,
+                                   (void *)&grpc_load_reporting_filter);
+}
+
+void grpc_load_reporting_plugin_shutdown() {}