Initial checkin of gRPC to third_party/

third_party/grpc/src/core/transport/connectivity_state.h

Index: third_party/grpc/src/core/transport/connectivity_state.h
diff --git a/third_party/grpc/src/core/transport/connectivity_state.h b/third_party/grpc/src/core/transport/connectivity_state.h
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index 0000000000000000000000000000000000000000..a4eb6652e551b815d28b51e29d11d93472088d73
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+++ b/third_party/grpc/src/core/transport/connectivity_state.h
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+/*
+ *
+ * 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.
+ *
+ */
+
+#ifndef GRPC_INTERNAL_CORE_TRANSPORT_CONNECTIVITY_STATE_H
+#define GRPC_INTERNAL_CORE_TRANSPORT_CONNECTIVITY_STATE_H
+
+#include <grpc/grpc.h>
+#include "src/core/iomgr/exec_ctx.h"
+
+typedef struct grpc_connectivity_state_watcher {
+  /** we keep watchers in a linked list */
+  struct grpc_connectivity_state_watcher *next;
+  /** closure to notify on change */
+  grpc_closure *notify;
+  /** the current state as believed by the watcher */
+  grpc_connectivity_state *current;
+} grpc_connectivity_state_watcher;
+
+typedef struct {
+  /** current connectivity state */
+  grpc_connectivity_state current_state;
+  /** all our watchers */
+  grpc_connectivity_state_watcher *watchers;
+  /** a name to help debugging */
+  char *name;
+} grpc_connectivity_state_tracker;
+
+extern int grpc_connectivity_state_trace;
+
+const char *grpc_connectivity_state_name(grpc_connectivity_state state);
+
+void grpc_connectivity_state_init(grpc_connectivity_state_tracker *tracker,
+                                  grpc_connectivity_state init_state,
+                                  const char *name);
+void grpc_connectivity_state_destroy(grpc_exec_ctx *exec_ctx,
+                                     grpc_connectivity_state_tracker *tracker);
+
+/** Set connectivity state; not thread safe; access must be serialized with an
+ * external lock */
+void grpc_connectivity_state_set(grpc_exec_ctx *exec_ctx,
+                                 grpc_connectivity_state_tracker *tracker,
+                                 grpc_connectivity_state state,
+                                 const char *reason);
+
+grpc_connectivity_state grpc_connectivity_state_check(
+    grpc_connectivity_state_tracker *tracker);
+
+/** Return 1 if the channel should start connecting, 0 otherwise.
+    If current==NULL cancel notify if it is already queued (success==0 in that
+    case) */
+int grpc_connectivity_state_notify_on_state_change(
+    grpc_exec_ctx *exec_ctx, grpc_connectivity_state_tracker *tracker,
+    grpc_connectivity_state *current, grpc_closure *notify);
+
+#endif /* GRPC_INTERNAL_CORE_TRANSPORT_CONNECTIVITY_STATE_H */