include/grpc/compression.h

/*
 *
 * Copyright 2015, Google Inc.
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 * modification, are permitted provided that the following conditions are
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 *
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 * in the documentation and/or other materials provided with the
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 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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#ifndef GRPC_COMPRESSION_H
#define GRPC_COMPRESSION_H

/** To be used in channel arguments */
#define GRPC_COMPRESSION_LEVEL_ARG "grpc.compression_level"

/* The various compression algorithms supported by GRPC */
typedef enum {
  GRPC_COMPRESS_NONE = 0,
  GRPC_COMPRESS_DEFLATE,
  GRPC_COMPRESS_GZIP,
  /* TODO(ctiller): snappy */
  GRPC_COMPRESS_ALGORITHMS_COUNT
} grpc_compression_algorithm;

typedef enum {
  GRPC_COMPRESS_LEVEL_NONE = 0,
  GRPC_COMPRESS_LEVEL_LOW,
  GRPC_COMPRESS_LEVEL_MED,
  GRPC_COMPRESS_LEVEL_HIGH,
  GRPC_COMPRESS_LEVEL_COUNT
} grpc_compression_level;

/** Parses \a name as a grpc_compression_algorithm instance, updating \a
 * algorithm. Returns 1 upon success, 0 otherwise. */
int grpc_compression_algorithm_parse(const char *name,
                                     grpc_compression_algorithm *algorithm);

/** Updates \a name with the encoding name corresponding to a valid \a
 * algorithm.  Returns 1 upon success, 0 otherwise. */
int grpc_compression_algorithm_name(grpc_compression_algorithm algorithm,
                                    char **name);

/** Returns the compression level corresponding to \a algorithm.
 *
 * It abort()s for unknown algorithms. */
grpc_compression_level grpc_compression_level_for_algorithm(
    grpc_compression_algorithm algorithm);

/** Returns the compression algorithm corresponding to \a level.
 *
 * It abort()s for unknown levels . */
grpc_compression_algorithm grpc_compression_algorithm_for_level(
    grpc_compression_level level);

#endif /* GRPC_COMPRESSION_H */