src/common/di_ops.h

   1 /* Copyright (c) 2003-2004, Roger Dingledine
   2  * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
   3  * Copyright (c) 2007-2013, The Tor Project, Inc. */
   4 /* See LICENSE for licensing information */
   5
   6 /**
   7  * \file di_ops.h
   8  * \brief Headers for di_ops.c
   9  **/
  10
  11 #ifndef TOR_DI_OPS_H
  12 #define TOR_DI_OPS_H
  13
  14 #include "orconfig.h"
  15 #include "torint.h"
  16
  17 int tor_memcmp(const void *a, const void *b, size_t sz);
  18 int tor_memeq(const void *a, const void *b, size_t sz);
  19 #define tor_memneq(a,b,sz) (!tor_memeq((a),(b),(sz)))
  20
  21 /** Alias for the platform's memcmp() function.  This function is
  22  * <em>not</em> data-independent: we define this alias so that we can
  23  * mark cases where we are deliberately using a data-dependent memcmp()
  24  * implementation.
  25  */
  26 #define fast_memcmp(a,b,c) (memcmp((a),(b),(c)))
  27 #define fast_memeq(a,b,c)  (0==memcmp((a),(b),(c)))
  28 #define fast_memneq(a,b,c) (0!=memcmp((a),(b),(c)))
  29
  30 int safe_mem_is_zero(const void *mem, size_t sz);
  31
  32 /** A type for a map from DIGEST256_LEN-byte blobs to void*, such that
  33  * data lookups take an amount of time proportional only to the size
  34  * of the map, and not to the position or presence of the item in the map.
  35  *
  36  * Not efficient for large maps! */
  37 typedef struct di_digest256_map_t di_digest256_map_t;
  38 typedef void (*dimap_free_fn)(void *);
  39
  40 void dimap_free(di_digest256_map_t *map, dimap_free_fn free_fn);
  41 void dimap_add_entry(di_digest256_map_t **map,
  42                      const uint8_t *key, void *val);
  43 void *dimap_search(const di_digest256_map_t *map, const uint8_t *key,
  44                    void *dflt_val);
  45
  46 #endif
  47