filters/xz/blkcache.h

   1 /* nbdkit
   2  * Copyright Red Hat
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   4  * Redistribution and use in source and binary forms, with or without
   5  * modification, are permitted provided that the following conditions are
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   9  * notice, this list of conditions and the following disclaimer.
  10  *
  11  * * Redistributions in binary form must reproduce the above copyright
  12  * notice, this list of conditions and the following disclaimer in the
  13  * documentation and/or other materials provided with the distribution.
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  15  * * Neither the name of Red Hat nor the names of its contributors may be
  16  * used to endorse or promote products derived from this software without
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  19  * THIS SOFTWARE IS PROVIDED BY RED HAT AND CONTRIBUTORS ''AS IS'' AND
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  22  * PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL RED HAT OR
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  29  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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  31  */
  32
  33 #ifndef NBDKIT_BLKCACHE_H
  34 #define NBDKIT_BLKCACHE_H
  35
  36 typedef struct blkcache blkcache;
  37
  38 typedef struct blkcache_stats {
  39   size_t hits;
  40   size_t misses;
  41 } blkcache_stats;
  42
  43 extern blkcache *new_blkcache (size_t maxdepth);
  44 extern void free_blkcache (blkcache *) __attribute__ ((__nonnull__ (1)));
  45 extern char *get_block (blkcache *, uint64_t offset,
  46                         uint64_t *start, uint64_t *size)
  47   __attribute__ ((__nonnull__ (1, 3, 4)));
  48 extern int put_block (blkcache *, uint64_t start, uint64_t size, char *data)
  49   __attribute__ ((__nonnull__ (1, 4)));
  50 extern void blkcache_get_stats (blkcache *, blkcache_stats *ret)
  51   __attribute__ ((__nonnull__ (1, 2)));
  52
  53 #endif /* NBDKIT_XZFILE_H */