1 files changed, 92 insertions, 0 deletions
diff --git a/src/core/channel/connectivity_state.c b/src/core/channel/connectivity_state.c
new file mode 100644
index 0000000000..566a2c3344
--- /dev/null
+++ b/src/core/channel/connectivity_state.c
@@ -0,0 +1,92 @@
+/*
+ *
+ * Copyright 2015, 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 "src/core/channel/connectivity_state.h"
+#include <grpc/support/alloc.h>
+
+void grpc_connectivity_state_init(grpc_connectivity_state_tracker *tracker, grpc_connectivity_state init_state) {
+	tracker->current_state = init_state;
+	tracker->watchers = NULL;
+}
+
+void grpc_connectivity_state_destroy(grpc_connectivity_state_tracker *tracker) {
+  grpc_connectivity_state_watcher *w;
+  while ((w = tracker->watchers)) {
+  	tracker->watchers = w->next;
+
+  	if (GRPC_CHANNEL_FATAL_FAILURE != *w->current) {
+  		*w->current = GRPC_CHANNEL_FATAL_FAILURE;
+  		grpc_iomgr_add_callback(w->notify);
+  	} else {
+  		grpc_iomgr_add_delayed_callback(w->notify, 0);
+  	}
+  	gpr_free(w);
+  }
+}
+
+grpc_connectivity_state grpc_connectivity_state_check(grpc_connectivity_state_tracker *tracker) {
+	return tracker->current_state;
+}
+
+int grpc_connectivity_state_notify_on_state_change(grpc_connectivity_state_tracker *tracker, grpc_connectivity_state *current, grpc_iomgr_closure *notify) {
+  if (tracker->current_state != *current) {
+    *current = tracker->current_state;
+    grpc_iomgr_add_callback(notify);
+  } else {
+	  grpc_connectivity_state_watcher *w = gpr_malloc(sizeof(*w));
+	  w->current = current;
+	  w->notify = notify;
+    w->next = tracker->watchers;
+    tracker->watchers = w;
+  }
+  return tracker->current_state == GRPC_CHANNEL_IDLE;
+}
+
+void grpc_connectivity_state_set(grpc_connectivity_state_tracker *tracker, grpc_connectivity_state state) {
+  grpc_connectivity_state_watcher *new = NULL;
+  grpc_connectivity_state_watcher *w;
+  tracker->current_state = state;
+  while ((w = tracker->watchers)) {
+    tracker->watchers = w->next;
+
+    if (state != *w->current) {
+      *w->current = state;
+      grpc_iomgr_add_callback(w->notify);
+      gpr_free(w);
+    } else {
+      w->next = new;
+      new = w;
+    }
+  }
+  tracker->watchers = new;
+}