| /* |
| * |
| * 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_SUPPORT_BACKOFF_H |
| #define GRPC_CORE_LIB_SUPPORT_BACKOFF_H |
| |
| #include <grpc/support/time.h> |
| |
| #ifdef __cplusplus |
| extern "C" { |
| #endif |
| |
| typedef struct { |
| /// const: how long to wait after the first failure before retrying |
| int64_t 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 |
| int64_t min_timeout_millis; |
| /// const: maximum time between retries in milliseconds |
| int64_t max_timeout_millis; |
| |
| /// random number generator |
| uint32_t rng_state; |
| |
| /// current retry timeout in milliseconds |
| int64_t current_timeout_millis; |
| } gpr_backoff; |
| |
| /// Initialize backoff machinery - does not need to be destroyed |
| void gpr_backoff_init(gpr_backoff *backoff, int64_t initial_connect_timeout, |
| double multiplier, double jitter, |
| int64_t min_timeout_millis, int64_t max_timeout_millis); |
| |
| /// Begin retry loop: returns a timespec for the NEXT retry |
| gpr_timespec gpr_backoff_begin(gpr_backoff *backoff, gpr_timespec now); |
| /// Step a retry loop: returns a timespec for the NEXT retry |
| gpr_timespec gpr_backoff_step(gpr_backoff *backoff, gpr_timespec now); |
| /// Reset the backoff, so the next gpr_backoff_step will be a gpr_backoff_begin |
| /// instead |
| void gpr_backoff_reset(gpr_backoff *backoff); |
| |
| #ifdef __cplusplus |
| } |
| #endif |
| |
| #endif /* GRPC_CORE_LIB_SUPPORT_BACKOFF_H */ |