diff options
Diffstat (limited to 'src/lib/ctime/di_ops.h')
-rw-r--r-- | src/lib/ctime/di_ops.h | 23 |
1 files changed, 22 insertions, 1 deletions
diff --git a/src/lib/ctime/di_ops.h b/src/lib/ctime/di_ops.h index 264b56a8c1..fea8f93e37 100644 --- a/src/lib/ctime/di_ops.h +++ b/src/lib/ctime/di_ops.h @@ -16,6 +16,8 @@ int tor_memcmp(const void *a, const void *b, size_t sz); int tor_memeq(const void *a, const void *b, size_t sz); +/** Perform a constant-time comparison of the <b>sz</b> bytes at <b>a</b> and + * <b>b</b>, yielding true if they are different, and false otherwise. */ #define tor_memneq(a,b,sz) (!tor_memeq((a),(b),(sz))) /** Alias for the platform's memcmp() function. This function is @@ -24,7 +26,19 @@ int tor_memeq(const void *a, const void *b, size_t sz); * implementation. */ #define fast_memcmp(a,b,c) (memcmp((a),(b),(c))) +/** Alias for the platform's memcmp() function, for use in testing equality. + * + * This function is <em>not</em> data-independent: we define this alias so + * that we can mark cases where we are deliberately using a data-dependent + * memcmp() implementation. + */ #define fast_memeq(a,b,c) (0==memcmp((a),(b),(c))) +/** Alias for the platform's memcmp() function, for use in testing inequality. + * + * This function is <em>not</em> data-independent: we define this alias so + * that we can mark cases where we are deliberately using a data-dependent + * memcmp() implementation. + */ #define fast_memneq(a,b,c) (0!=memcmp((a),(b),(c))) int safe_mem_is_zero(const void *mem, size_t sz); @@ -35,9 +49,17 @@ int safe_mem_is_zero(const void *mem, size_t sz); * * Not efficient for large maps! */ typedef struct di_digest256_map_t di_digest256_map_t; +/** + * Type for a function used to free members of a di_digest256_map_t. + **/ typedef void (*dimap_free_fn)(void *); void dimap_free_(di_digest256_map_t *map, dimap_free_fn free_fn); +/** + * @copydoc dimap_free_ + * + * Additionally, set the pointer <b>map</b> to NULL. + **/ #define dimap_free(map, free_fn) \ do { \ dimap_free_((map), (free_fn)); \ @@ -52,4 +74,3 @@ int select_array_member_cumulative_timei(const uint64_t *entries, uint64_t total, uint64_t rand_val); #endif /* !defined(TOR_DI_OPS_H) */ - |