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|
-- |
-- Module : Crypto.Random.API
-- License : BSD-style
-- Maintainer : Vincent Hanquez <vincent@snarc.org>
-- Stability : experimental
-- Portability : Good
--
-- Deprecated interface for compatibility of crypto-random-api user
-- with crypto-random
--
module Crypto.Random.API
( CPRG(..)
, cprgGenBytes
, genRandomBytes
, genRandomBytes'
, withRandomBytes
) where
import Data.ByteString (ByteString)
import Crypto.Random
-- | Generate bytes using the CPRG and the number specified.
--
-- For user of the API, it's recommended to use genRandomBytes
-- instead of this method directly. the CPRG need to be able
-- to supply at minimum 2^20 bytes at a time.
cprgGenBytes :: CPRG g => Int -> g -> (ByteString, g)
cprgGenBytes n cprg = cprgGenerate n cprg
-- | Generate bytes using the cprg in parameter.
--
-- If the number of bytes requested is really high,
-- it's preferable to use 'genRandomBytes' for better memory efficiency.
{-# DEPRECATED genRandomBytes "use cprgGenerate from Crypto.Random instead" #-}
genRandomBytes :: CPRG g
=> Int -- ^ number of bytes to return
-> g -- ^ CPRG to use
-> (ByteString, g)
genRandomBytes n cprg = cprgGenerate n cprg
-- | Generate bytes using the cprg in parameter.
--
-- This is not tail recursive and an excessive len (>= 2^29) parameter would
-- result in stack overflow.
genRandomBytes' :: CPRG g => Int -- ^ number of bytes to return
-> g -- ^ CPRG to use
-> ([ByteString], g)
genRandomBytes' len rng
| len < 0 = error "genBytes: cannot request negative amount of bytes."
| otherwise = loop rng len
where loop g n
| n == 0 = ([], g)
| otherwise = let itBytes = min (2^(20:: Int)) n
(bs, g') = cprgGenBytes itBytes g
(l, g'') = genRandomBytes' (n-itBytes) g'
in (bs:l, g'')
|
