;;;; sha256-api.scm  -*- Scheme -*-
;;;; Kon Lovett, Jul '18

#>
#define SHA2_USE_INTTYPES_H 1
#define SHA2_USE_MEMSET_MEMCPY 1
#define SHA2_LITTLE_ENDIAN 1234
#define SHA2_BIG_ENDIAN    4321
#ifdef C_BIG_ENDIAN
# define SHA2_BYTE_ORDER SHA2_BIG_ENDIAN
#endif
#ifdef C_LITTLE_ENDIAN
# define SHA2_BYTE_ORDER SHA2_LITTLE_ENDIAN
#endif

#define SHA256
#include "sha2-base.c"
#undef SHA256

#undef SHA2_LITTLE_ENDIAN
#undef SHA2_BIG_ENDIAN
#undef SHA2_BYTE_ORDER
#undef SHA2_USE_MEMSET_MEMCPY
#undef SHA2_USE_INTTYPES_H

static void shim_SHA256_Final(SHA256_CTX* context, sha2_byte digest[]) {
  SHA256_Final(digest, context);
}
<#

(module sha256-api

(;export
  name version
  context-size digest-length block-length
  init update final raw-update)

(import scheme
  (chicken base)
  (chicken foreign))

;;

(define name 'sha256)
(define version "1.0.1")

(define-foreign-variable digest_length unsigned-int "SHA256_DIGEST_LENGTH")
(define-foreign-variable block_length unsigned-int "SHA256_BLOCK_LENGTH")
(define-foreign-variable context_size unsigned-int "sizeof(SHA256_CTX)")

(define context-size context_size)
(define digest-length digest_length)
(define block-length block_length)

(define init (foreign-lambda void "SHA256_Init" c-pointer))
(define update (foreign-lambda void "SHA256_Update" c-pointer scheme-pointer unsigned-int))
(define final (foreign-lambda void "shim_SHA256_Final" c-pointer scheme-pointer))
(define raw-update (foreign-lambda void "SHA256_Update" c-pointer c-pointer unsigned-int))

) ;module sha256-api