constantine/bindings/lib_hashes.nim

34 lines
1.4 KiB
Nim

# Constantine
# Copyright (c) 2018-2019 Status Research & Development GmbH
# Copyright (c) 2020-Present Mamy André-Ratsimbazafy
# Licensed and distributed under either of
# * MIT license (license terms in the root directory or at http://opensource.org/licenses/MIT).
# * Apache v2 license (license terms in the root directory or at http://www.apache.org/licenses/LICENSE-2.0).
# at your option. This file may not be copied, modified, or distributed except according to those terms.
# ############################################################
#
# Hashes
#
# ############################################################
import ../constantine/zoo_exports
# Modify per-module prefix if needed
# ----------------------------------------
# static:
# prefix_sha256 = prefix_ffi & "sha256_"
import ../constantine/hashes
func sha256_hash(digest: var array[32, byte], message: openArray[byte], clearMem: bool) {.libPrefix: "ctt_".} =
## Compute the SHA-256 hash of message
## and store the result in digest.
## Optionally, clear the memory buffer used.
# There is an extra indirect function call as we use a generic `hash` concept but:
# - the indirection saves space (instead of duplicating `hash`)
# - minimal overhead compared to hashing time
# - Can be tail-call optimized into a goto jump instead of call/return
# - Can be LTO-optimized
sha256.hash(digest, message, clearMem)