1*0957b409SSimon J. Gerraty /*
2*0957b409SSimon J. Gerraty * Copyright (c) 2016 Thomas Pornin <pornin@bolet.org>
3*0957b409SSimon J. Gerraty *
4*0957b409SSimon J. Gerraty * Permission is hereby granted, free of charge, to any person obtaining
5*0957b409SSimon J. Gerraty * a copy of this software and associated documentation files (the
6*0957b409SSimon J. Gerraty * "Software"), to deal in the Software without restriction, including
7*0957b409SSimon J. Gerraty * without limitation the rights to use, copy, modify, merge, publish,
8*0957b409SSimon J. Gerraty * distribute, sublicense, and/or sell copies of the Software, and to
9*0957b409SSimon J. Gerraty * permit persons to whom the Software is furnished to do so, subject to
10*0957b409SSimon J. Gerraty * the following conditions:
11*0957b409SSimon J. Gerraty *
12*0957b409SSimon J. Gerraty * The above copyright notice and this permission notice shall be
13*0957b409SSimon J. Gerraty * included in all copies or substantial portions of the Software.
14*0957b409SSimon J. Gerraty *
15*0957b409SSimon J. Gerraty * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
16*0957b409SSimon J. Gerraty * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
17*0957b409SSimon J. Gerraty * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
18*0957b409SSimon J. Gerraty * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
19*0957b409SSimon J. Gerraty * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
20*0957b409SSimon J. Gerraty * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
21*0957b409SSimon J. Gerraty * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
22*0957b409SSimon J. Gerraty * SOFTWARE.
23*0957b409SSimon J. Gerraty */
24*0957b409SSimon J. Gerraty
25*0957b409SSimon J. Gerraty #include "inner.h"
26*0957b409SSimon J. Gerraty
27*0957b409SSimon J. Gerraty /* see inner.h */
28*0957b409SSimon J. Gerraty void
br_i32_encode(void * dst,size_t len,const uint32_t * x)29*0957b409SSimon J. Gerraty br_i32_encode(void *dst, size_t len, const uint32_t *x)
30*0957b409SSimon J. Gerraty {
31*0957b409SSimon J. Gerraty unsigned char *buf;
32*0957b409SSimon J. Gerraty size_t k;
33*0957b409SSimon J. Gerraty
34*0957b409SSimon J. Gerraty buf = dst;
35*0957b409SSimon J. Gerraty
36*0957b409SSimon J. Gerraty /*
37*0957b409SSimon J. Gerraty * Compute the announced size of x in bytes; extra bytes are
38*0957b409SSimon J. Gerraty * filled with zeros.
39*0957b409SSimon J. Gerraty */
40*0957b409SSimon J. Gerraty k = (x[0] + 7) >> 3;
41*0957b409SSimon J. Gerraty while (len > k) {
42*0957b409SSimon J. Gerraty *buf ++ = 0;
43*0957b409SSimon J. Gerraty len --;
44*0957b409SSimon J. Gerraty }
45*0957b409SSimon J. Gerraty
46*0957b409SSimon J. Gerraty /*
47*0957b409SSimon J. Gerraty * Now we use k as index within x[]. That index starts at 1;
48*0957b409SSimon J. Gerraty * we initialize it to the topmost complete word, and process
49*0957b409SSimon J. Gerraty * any remaining incomplete word.
50*0957b409SSimon J. Gerraty */
51*0957b409SSimon J. Gerraty k = (len + 3) >> 2;
52*0957b409SSimon J. Gerraty switch (len & 3) {
53*0957b409SSimon J. Gerraty case 3:
54*0957b409SSimon J. Gerraty *buf ++ = x[k] >> 16;
55*0957b409SSimon J. Gerraty /* fall through */
56*0957b409SSimon J. Gerraty case 2:
57*0957b409SSimon J. Gerraty *buf ++ = x[k] >> 8;
58*0957b409SSimon J. Gerraty /* fall through */
59*0957b409SSimon J. Gerraty case 1:
60*0957b409SSimon J. Gerraty *buf ++ = x[k];
61*0957b409SSimon J. Gerraty k --;
62*0957b409SSimon J. Gerraty }
63*0957b409SSimon J. Gerraty
64*0957b409SSimon J. Gerraty /*
65*0957b409SSimon J. Gerraty * Encode all complete words.
66*0957b409SSimon J. Gerraty */
67*0957b409SSimon J. Gerraty while (k > 0) {
68*0957b409SSimon J. Gerraty br_enc32be(buf, x[k]);
69*0957b409SSimon J. Gerraty k --;
70*0957b409SSimon J. Gerraty buf += 4;
71*0957b409SSimon J. Gerraty }
72*0957b409SSimon J. Gerraty }
73