src/core/ext/filters/client_channel/retry_throttle.h

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#ifndef GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_RETRY_THROTTLE_H
#define GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_RETRY_THROTTLE_H

#include <stdbool.h>

/// Tracks retry throttling data for an individual server name.
typedef struct grpc_server_retry_throttle_data grpc_server_retry_throttle_data;

/// Records a failure.  Returns true if it's okay to send a retry.
bool grpc_server_retry_throttle_data_record_failure(
    grpc_server_retry_throttle_data* throttle_data);
/// Records a success.
void grpc_server_retry_throttle_data_record_success(
    grpc_server_retry_throttle_data* throttle_data);

grpc_server_retry_throttle_data* grpc_server_retry_throttle_data_ref(
    grpc_server_retry_throttle_data* throttle_data);
void grpc_server_retry_throttle_data_unref(
    grpc_server_retry_throttle_data* throttle_data);

/// Initializes global map of failure data for each server name.
void grpc_retry_throttle_map_init();
/// Shuts down global map of failure data for each server name.
void grpc_retry_throttle_map_shutdown();

/// Returns a reference to the failure data for \a server_name, creating
/// a new entry if needed.
/// Caller must eventually unref via \a grpc_server_retry_throttle_data_unref().
grpc_server_retry_throttle_data* grpc_retry_throttle_map_get_data_for_server(
    const char* server_name, int max_milli_tokens, int milli_token_ratio);

#endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_RETRY_THROTTLE_H */