1 /* 2 * Copyright (c) 2016 Thomas Pornin <pornin@bolet.org> 3 * 4 * Permission is hereby granted, free of charge, to any person obtaining 5 * a copy of this software and associated documentation files (the 6 * "Software"), to deal in the Software without restriction, including 7 * without limitation the rights to use, copy, modify, merge, publish, 8 * distribute, sublicense, and/or sell copies of the Software, and to 9 * permit persons to whom the Software is furnished to do so, subject to 10 * the following conditions: 11 * 12 * The above copyright notice and this permission notice shall be 13 * included in all copies or substantial portions of the Software. 14 * 15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 16 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 17 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 18 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS 19 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN 20 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN 21 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 22 * SOFTWARE. 23 */ 24 25 #include "inner.h" 26 27 /* see inner.h */ 28 void 29 br_i32_decode(uint32_t *x, const void *src, size_t len) 30 { 31 const unsigned char *buf; 32 size_t u, v; 33 34 buf = src; 35 u = len; 36 v = 1; 37 for (;;) { 38 if (u < 4) { 39 uint32_t w; 40 41 if (u < 2) { 42 if (u == 0) { 43 break; 44 } else { 45 w = buf[0]; 46 } 47 } else { 48 if (u == 2) { 49 w = br_dec16be(buf); 50 } else { 51 w = ((uint32_t)buf[0] << 16) 52 | br_dec16be(buf + 1); 53 } 54 } 55 x[v ++] = w; 56 break; 57 } else { 58 u -= 4; 59 x[v ++] = br_dec32be(buf + u); 60 } 61 } 62 x[0] = br_i32_bit_length(x + 1, v - 1); 63 } 64