1 /*
2  * Copyright (C) 2020 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #include "Utils.h"
18 
19 #include <string.h>
20 
21 namespace android {
22 
zeroMemory(uint8_t * data,size_t size)23 void zeroMemory(uint8_t* data, size_t size) {
24     memset(data, 0, size);
25 }
26 
HexString(const void * bytes,size_t len)27 std::string HexString(const void* bytes, size_t len) {
28     LOG_ALWAYS_FATAL_IF(len > 0 && bytes == nullptr, "%p %zu", bytes, len);
29 
30     // b/132916539: Doing this the 'C way', std::setfill triggers ubsan implicit conversion
31     const uint8_t* bytes8 = static_cast<const uint8_t*>(bytes);
32     const char chars[] = "0123456789abcdef";
33     std::string result;
34     result.resize(len * 2);
35 
36     for (size_t i = 0; i < len; i++) {
37         const auto c = bytes8[i];
38         result[2 * i] = chars[c >> 4];
39         result[2 * i + 1] = chars[c & 0xf];
40     }
41 
42     return result;
43 }
44 
45 } // namespace android
46