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diff --git a/src/core/lib/backoff/backoff.h b/src/core/lib/backoff/backoff.h
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+++ b/src/core/lib/backoff/backoff.h
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+/*
+ *
+ * Copyright 2016 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.
+ *
+ */
+
+#ifndef GRPC_CORE_LIB_BACKOFF_BACKOFF_H
+#define GRPC_CORE_LIB_BACKOFF_BACKOFF_H
+
+#include "src/core/lib/iomgr/exec_ctx.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+typedef struct {
+  /// const:  how long to wait after the first failure before retrying
+  grpc_millis initial_connect_timeout;
+  /// const: factor with which to multiply backoff after a failed retry
+  double multiplier;
+  /// const: amount to randomize backoffs
+  double jitter;
+  /// const: minimum time between retries in milliseconds
+  grpc_millis min_timeout_millis;
+  /// const: maximum time between retries in milliseconds
+  grpc_millis max_timeout_millis;
+
+  /// random number generator
+  uint32_t rng_state;
+
+  /// current retry timeout in milliseconds
+  grpc_millis current_timeout_millis;
+} grpc_backoff;
+
+/// Initialize backoff machinery - does not need to be destroyed
+void grpc_backoff_init(grpc_backoff *backoff,
+                       grpc_millis initial_connect_timeout, double multiplier,
+                       double jitter, grpc_millis min_timeout_millis,
+                       grpc_millis max_timeout_millis);
+
+/// Begin retry loop: returns a timespec for the NEXT retry
+grpc_millis grpc_backoff_begin(grpc_exec_ctx *exec_ctx, grpc_backoff *backoff);
+/// Step a retry loop: returns a timespec for the NEXT retry
+grpc_millis grpc_backoff_step(grpc_exec_ctx *exec_ctx, grpc_backoff *backoff);
+/// Reset the backoff, so the next grpc_backoff_step will be a
+/// grpc_backoff_begin
+/// instead
+void grpc_backoff_reset(grpc_backoff *backoff);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* GRPC_CORE_LIB_BACKOFF_BACKOFF_H */