update.c


1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32

/* See LICENSE file for copyright and license details. */
#include "common.h"


void
libsha2_update(struct libsha2_state *restrict state, const void *restrict message_, size_t msglen)
{
	const char *restrict message = message_;
	size_t n, off;

	off = (state->message_size / 8) % state->chunk_size;
	state->message_size += msglen;
	msglen /= 8;

	if (off) {
		n = msglen < state->chunk_size - off ? msglen : state->chunk_size - off;
		memcpy(&state->chunk[off], message, n);
		if (off + n == state->chunk_size)
			libsha2_process(state, state->chunk);
		message += n;
		msglen -= n;
	}

	while (msglen >= state->chunk_size) {
		libsha2_process(state, (const unsigned char *)message);
		message += state->chunk_size;
		msglen -= state->chunk_size;
	}

	if (msglen)
		memcpy(state->chunk, message, msglen);
}