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/*
* Copyright (c) 2016 Thomas Pornin <[email protected]>
*
* Permission is hereby granted, free of charge, to any person obtaining
* a copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
#include "inner.h"
/* see inner.h */
void
br_i31_decode(uint32_t *x, const void *src, size_t len)
{
const unsigned char *buf;
size_t u, v;
uint32_t acc;
int acc_len;
buf = src;
u = len;
v = 1;
acc = 0;
acc_len = 0;
while (u -- > 0) {
uint32_t b;
b = buf[u];
acc |= (b << acc_len);
acc_len += 8;
if (acc_len >= 31) {
x[v ++] = acc & (uint32_t)0x7FFFFFFF;
acc_len -= 31;
acc = b >> (8 - acc_len);
}
}
if (acc_len != 0) {
x[v ++] = acc;
}
x[0] = br_i31_bit_length(x + 1, v - 1);
}
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