Functions | |
| UNIV_INLINE void | ut_rnd_set_seed (ulint seed) |
| UNIV_INLINE ulint | ut_rnd_gen_next_ulint (ulint rnd) |
| UNIV_INLINE ulint | ut_rnd_gen_ulint (void) |
| UNIV_INLINE ulint | ut_rnd_interval (ulint low, ulint high) |
| UNIV_INLINE ibool | ut_rnd_gen_ibool (void) |
| UNIV_INLINE ulint | ut_hash_ulint (ulint key, ulint table_size) |
| UNIV_INLINE ulint | ut_fold_ull (ib_uint64_t d) |
| UNIV_INLINE ulint | ut_fold_string (const char *str) |
| UNIV_INLINE ulint | ut_fold_ulint_pair (ulint n1, ulint n2) |
| UNIV_INLINE ulint | ut_fold_binary (const byte *str, ulint len) |
Variables | |
| ulint | ut_rnd_ulint_counter |
Detailed Description
Random numbers and hashing
Created 5/30/1994 Heikki Tuuri
Function Documentation
| UNIV_INLINE ulint ut_fold_binary | ( | const byte * | str, |
| ulint | len | ||
| ) |
Folds a binary string.
- Returns
- folded value
- Parameters
-
str in: string of bytes len in: length
| UNIV_INLINE ulint ut_fold_string | ( | const char * | str | ) |
Folds a character string ending in the null character.
- Returns
- folded value
- Parameters
-
str in: null-terminated string
| UNIV_INLINE ulint ut_fold_ulint_pair | ( | ulint | n1, |
| ulint | n2 | ||
| ) |
Folds a pair of ulints.
- Returns
- folded value
- Parameters
-
n1 in: ulint n2 in: ulint
| UNIV_INLINE ulint ut_fold_ull | ( | ib_uint64_t | d | ) |
Folds a 64-bit integer.
- Returns
- folded value
- Parameters
-
d in: 64-bit integer
| UNIV_INLINE ulint ut_hash_ulint | ( | ulint | key, |
| ulint | table_size | ||
| ) |
The following function generates a hash value for a ulint integer to a hash table of size table_size, which should be a prime or some random number for the hash table to work reliably.
- Returns
- hash value
- Parameters
-
key in: value to be hashed table_size in: hash table size
| UNIV_INLINE ibool ut_rnd_gen_ibool | ( | void | ) |
Generates a random iboolean value.
- Returns
- the random value
| UNIV_INLINE ulint ut_rnd_gen_next_ulint | ( | ulint | rnd | ) |
The following function generates a series of 'random' ulint integers.
- Returns
- the next 'random' number
- Parameters
-
rnd in: the previous random number value
| UNIV_INLINE ulint ut_rnd_gen_ulint | ( | void | ) |
The following function generates 'random' ulint integers which enumerate the value space of ulint integers in a pseudo random fashion. Note that the same integer is repeated always after 2 to power 32 calls to the generator (if ulint is 32-bit).
- Returns
- the 'random' number
| UNIV_INLINE ulint ut_rnd_interval | ( | ulint | low, |
| ulint | high | ||
| ) |
Generates a random integer from a given interval.
- Returns
- the 'random' number
- Parameters
-
low in: low limit; can generate also this value high in: high limit; can generate also this value
| UNIV_INLINE void ut_rnd_set_seed | ( | ulint | seed | ) |
This is used to set the random number seed.
- Parameters
-
seed in: seed
Variable Documentation
| ulint ut_rnd_ulint_counter |
Seed value of ut_rnd_gen_ulint()
