1 // Copyright 2022 Google LLC
2 //
3 // Licensed under the Apache License, Version 2.0 (the "License");
4 // you may not use this file except in compliance with the License.
5 // You may obtain a copy of the License at
6 //
7 //      http://www.apache.org/licenses/LICENSE-2.0
8 //
9 // Unless required by applicable law or agreed to in writing, software
10 // distributed under the License is distributed on an "AS IS" BASIS,
11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 // See the License for the specific language governing permissions and
13 // limitations under the License.
14 #include "config.h"
15 
16 #include "bifurcation.hpp"
17 
18 #include <fmt/format.h>
19 
20 #include <charconv>
21 #include <filesystem>
22 #include <fstream>
23 #include <nlohmann/json.hpp>
24 #include <optional>
25 #include <string_view>
26 #include <vector>
27 
28 namespace google
29 {
30 namespace ipmi
31 {
32 
33 BifurcationStatic::BifurcationStatic() :
34     BifurcationStatic(STATIC_BIFURCATION_CONFIG)
35 {
36 }
37 
38 BifurcationStatic::BifurcationStatic(std::string_view bifurcationFile) :
39     bifurcationFile(bifurcationFile)
40 {
41 }
42 
43 std::optional<std::vector<uint8_t>>
44     BifurcationStatic::getBifurcation(uint8_t index) noexcept
45 {
46     // Example valid data:
47     // {
48     //     "1": [8,8],
49     //     "2": [4, 4, 12]
50     // }
51     std::ifstream jsonFile(bifurcationFile.c_str());
52     if (!jsonFile.is_open())
53     {
54         fmt::print(stderr, "Unable to open file {} for bifurcation.\n",
55                    bifurcationFile.data());
56         return std::nullopt;
57     }
58 
59     nlohmann::json jsonData;
60     try
61     {
62         jsonData = nlohmann::json::parse(jsonFile, nullptr, false);
63     }
64     catch (const nlohmann::json::parse_error& ex)
65     {
66         fmt::print(
67             stderr,
68             "Failed to parse the static config. Parse error at byte {}\n",
69             ex.byte);
70         return std::nullopt;
71     }
72 
73     std::vector<uint8_t> vec;
74     try
75     {
76         std::string key = std::to_string(index);
77         auto value = jsonData[key];
78         value.get_to(vec);
79     }
80     catch (std::exception const& e)
81     {
82         fmt::print(stderr,
83                    "Failed to convert bifurcation value to vec[uin8_t]\n");
84         return std::nullopt;
85     }
86 
87     return vec;
88 }
89 
90 } // namespace ipmi
91 } // namespace google
92