package sodium_generic_hash_benchmark

import (
	"fmt"
	"unsafe"
)

// #cgo pkg-config: libsodium
// #include <stdlib.h>
// #include <sodium.h>
import "C"

func init() {
	var r int
	if r = int(C.sodium_init()); 0 != r {
		panic(fmt.Errorf("sodium_init(): rc = %d, expect rc = 0", r))
	}
}

func sodiumRandbytes(b []byte) {
	if 0 == len(b) {
		panic("target buffer is nil or zero-length")
	}

	var bp = unsafe.Pointer(&b[0])
	var bs = C.size_t(len(b))

	C.randombytes_buf(bp, bs)
}

func sodiumGenerichash(p, k, m []byte) int {
	var pp = (*C.uchar)(unsafe.Pointer(&p[0]))
	var ps = C.size_t(24)
	if cap(p) < int(ps) {
		panic("target buffer length less than required outlen")
	}

	var kp = (*C.uchar)(unsafe.Pointer(&k[0]))
	var ks = C.size_t(24)
	if len(k) < int(ks) {
		panic("key length less than required")
	}

	var mp = (*C.uchar)(unsafe.Pointer(&m[0]))
	var ms = C.ulonglong(len(m))
	if 0 == len(m) {
		panic("message buffer is nil or zero-length")
	}

	return int(C.crypto_generichash(pp, ps, mp, ms, kp, ks))
}