1 /* 2 3 Copyright (c) 2003-2018, Arvid Norberg 4 All rights reserved. 5 6 Redistribution and use in source and binary forms, with or without 7 modification, are permitted provided that the following conditions 8 are met: 9 10 * Redistributions of source code must retain the above copyright 11 notice, this list of conditions and the following disclaimer. 12 * Redistributions in binary form must reproduce the above copyright 13 notice, this list of conditions and the following disclaimer in 14 the documentation and/or other materials provided with the distribution. 15 * Neither the name of the author nor the names of its 16 contributors may be used to endorse or promote products derived 17 from this software without specific prior written permission. 18 19 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 20 AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE 23 LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 POSSIBILITY OF SUCH DAMAGE. 30 31 */ 32 33 #include "libtorrent/hex.hpp" 34 35 namespace libtorrent { 36 37 namespace aux { 38 hex_to_int(char in)39 int hex_to_int(char in) 40 { 41 if (in >= '0' && in <= '9') return int(in) - '0'; 42 if (in >= 'A' && in <= 'F') return int(in) - 'A' + 10; 43 if (in >= 'a' && in <= 'f') return int(in) - 'a' + 10; 44 return -1; 45 } 46 is_hex(span<char const> in)47 bool is_hex(span<char const> in) 48 { 49 for (char const c : in) 50 { 51 int const t = hex_to_int(c); 52 if (t == -1) return false; 53 } 54 return true; 55 } 56 from_hex(span<char const> in,char * out)57 bool from_hex(span<char const> in, char* out) 58 { 59 for (auto i = in.begin(), end = in.end(); i != end; ++i, ++out) 60 { 61 int const t1 = aux::hex_to_int(*i); 62 if (t1 == -1) return false; 63 *out = char(t1 << 4); 64 ++i; 65 int const t2 = aux::hex_to_int(*i); 66 if (t2 == -1) return false; 67 *out |= t2 & 15; 68 } 69 return true; 70 } 71 72 extern char const hex_chars[]; 73 74 char const hex_chars[] = "0123456789abcdef"; to_hex(char const * in,int const len,char * out)75 void to_hex(char const* in, int const len, char* out) 76 { 77 int idx = 0; 78 for (int i = 0; i < len; ++i) 79 { 80 out[idx++] = hex_chars[std::uint8_t(in[i]) >> 4]; 81 out[idx++] = hex_chars[std::uint8_t(in[i]) & 0xf]; 82 } 83 } 84 to_hex(span<char const> in)85 std::string to_hex(span<char const> in) 86 { 87 std::string ret; 88 if (!in.empty()) 89 { 90 ret.resize(std::size_t(in.size() * 2)); 91 to_hex(in.data(), int(in.size()), &ret[0]); 92 } 93 return ret; 94 } 95 to_hex(span<char const> in,char * out)96 void to_hex(span<char const> in, char* out) 97 { 98 to_hex(in.data(), int(in.size()), out); 99 out[in.size() * 2] = '\0'; 100 } 101 102 } // aux namespace 103 104 } 105