1// Licensed to the Apache Software Foundation (ASF) under one
2// or more contributor license agreements. See the NOTICE file
3// distributed with this work for additional information
4// regarding copyright ownership. The ASF licenses this file
5// to you under the Apache License, Version 2.0 (the
6// "License"); you may not use this file except in compliance
7// with the License. You may obtain a copy of the License at
8//
9// http://www.apache.org/licenses/LICENSE-2.0
10//
11// Unless required by applicable law or agreed to in writing,
12// software distributed under the License is distributed on an
13// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
14// KIND, either express or implied. See the License for the
15// specific language governing permissions and limitations
16// under the License.
17
18#ifndef ARROW_UTIL_STRING_UTIL_H
19#define ARROW_UTIL_STRING_UTIL_H
20
21#include <algorithm>
22#include <string>
23
24#include "arrow/status.h"
25#include "arrow/util/string_view.h"
26
27namespace arrow {
28
29static const char* kAsciiTable = "0123456789ABCDEF";
30
31static inline std::string HexEncode(const char* data, size_t length) {
32 std::string hex_string;
33 hex_string.reserve(length * 2);
34 for (size_t j = 0; j < length; ++j) {
35 // Convert to 2 base16 digits
36 hex_string.push_back(kAsciiTable[data[j] >> 4]);
37 hex_string.push_back(kAsciiTable[data[j] & 15]);
38 }
39 return hex_string;
40}
41
42static inline std::string HexEncode(const uint8_t* data, int32_t length) {
43 return HexEncode(reinterpret_cast<const char*>(data), length);
44}
45
46static inline std::string HexEncode(util::string_view str) {
47 return HexEncode(str.data(), str.size());
48}
49
50static inline Status ParseHexValue(const char* data, uint8_t* out) {
51 char c1 = data[0];
52 char c2 = data[1];
53
54 const char* pos1 = std::lower_bound(kAsciiTable, kAsciiTable + 16, c1);
55 const char* pos2 = std::lower_bound(kAsciiTable, kAsciiTable + 16, c2);
56
57 // Error checking
58 if (*pos1 != c1 || *pos2 != c2) {
59 return Status::Invalid("Encountered non-hex digit");
60 }
61
62 *out = static_cast<uint8_t>((pos1 - kAsciiTable) << 4 | (pos2 - kAsciiTable));
63 return Status::OK();
64}
65
66} // namespace arrow
67
68#endif // ARROW_UTIL_STRING_UTIL_H
69