xref: /openbmc/bmcweb/http/logging.hpp (revision cef8cf9a)
1 #pragma once
2 
3 #include "bmcweb_config.h"
4 
5 #include <bit>
6 #include <format>
7 #include <iostream>
8 #include <source_location>
9 #include <string_view>
10 #include <system_error>
11 
12 // NOLINTBEGIN(readability-convert-member-functions-to-static, cert-dcl58-cpp)
13 template <>
14 struct std::formatter<void*>
15 {
16     constexpr auto parse(std::format_parse_context& ctx)
17     {
18         return ctx.begin();
19     }
20     auto format(const void*& ptr, auto& ctx) const
21     {
22         return std::format_to(ctx.out(), "{}",
23                               std::to_string(std::bit_cast<size_t>(ptr)));
24     }
25 };
26 // NOLINTEND(readability-convert-member-functions-to-static, cert-dcl58-cpp)
27 
28 namespace crow
29 {
30 enum class LogLevel
31 {
32     Disabled = 0,
33     Critical,
34     Error,
35     Warning,
36     Info,
37     Debug,
38     Enabled,
39 };
40 
41 // Mapping of the external loglvl name to internal loglvl
42 constexpr std::array<std::string_view, 7> mapLogLevelFromName{
43     "DISABLED", "CRITICAL", "ERROR", "WARNING", "INFO", "DEBUG", "ENABLED"};
44 
45 constexpr crow::LogLevel getLogLevelFromName(std::string_view name)
46 {
47     const auto* iter = std::ranges::find(mapLogLevelFromName, name);
48     if (iter != mapLogLevelFromName.end())
49     {
50         return static_cast<LogLevel>(iter - mapLogLevelFromName.begin());
51     }
52     return crow::LogLevel::Disabled;
53 }
54 
55 // configured bmcweb LogLevel
56 constexpr crow::LogLevel bmcwebCurrentLoggingLevel =
57     getLogLevelFromName(BMCWEB_LOGGING_LEVEL);
58 
59 template <typename T>
60 const void* logPtr(T p)
61 {
62     static_assert(std::is_pointer<T>::value,
63                   "Can't use logPtr without pointer");
64     return std::bit_cast<const void*>(p);
65 }
66 
67 template <LogLevel level, typename... Args>
68 inline void vlog(std::format_string<Args...>&& format, Args&&... args,
69                  const std::source_location& loc) noexcept
70 {
71     if constexpr (bmcwebCurrentLoggingLevel < level)
72     {
73         return;
74     }
75     constexpr size_t stringIndex = static_cast<size_t>(level);
76     static_assert(stringIndex < mapLogLevelFromName.size(),
77                   "Missing string for level");
78     constexpr std::string_view levelString = mapLogLevelFromName[stringIndex];
79     std::string_view filename = loc.file_name();
80     filename = filename.substr(filename.rfind('/') + 1);
81     std::string logLocation;
82     try
83     {
84         // TODO, multiple static analysis tools flag that this could potentially
85         // throw Based on the documentation, it shouldn't throw, so long as none
86         // of the formatters throw, so unclear at this point why this try/catch
87         // is required, but add it to silence the static analysis tools.
88         logLocation = std::format("[{} {}:{}] ", levelString, filename,
89                                   loc.line());
90         logLocation += std::format(std::move(format),
91                                    std::forward<Args>(args)...);
92     }
93     catch (const std::format_error& /*error*/)
94     {
95         logLocation += "Failed to format";
96         // Nothing more we can do here if logging is broken.
97     }
98     logLocation += '\n';
99     // Intentionally ignore error return.
100     fwrite(logLocation.data(), sizeof(std::string::value_type),
101            logLocation.size(), stdout);
102     fflush(stdout);
103 }
104 } // namespace crow
105 
106 template <typename... Args>
107 struct BMCWEB_LOG_CRITICAL
108 {
109     // NOLINTNEXTLINE(google-explicit-constructor)
110     BMCWEB_LOG_CRITICAL(std::format_string<Args...> format, Args&&... args,
111                         const std::source_location& loc =
112                             std::source_location::current()) noexcept
113     {
114         crow::vlog<crow::LogLevel::Critical, Args...>(
115             std::move(format), std::forward<Args>(args)..., loc);
116     }
117 };
118 
119 template <typename... Args>
120 struct BMCWEB_LOG_ERROR
121 {
122     // NOLINTNEXTLINE(google-explicit-constructor)
123     BMCWEB_LOG_ERROR(std::format_string<Args...> format, Args&&... args,
124                      const std::source_location& loc =
125                          std::source_location::current()) noexcept
126     {
127         crow::vlog<crow::LogLevel::Error, Args...>(
128             std::move(format), std::forward<Args>(args)..., loc);
129     }
130 };
131 
132 template <typename... Args>
133 struct BMCWEB_LOG_WARNING
134 {
135     // NOLINTNEXTLINE(google-explicit-constructor)
136     BMCWEB_LOG_WARNING(std::format_string<Args...> format, Args&&... args,
137                        const std::source_location& loc =
138                            std::source_location::current()) noexcept
139     {
140         crow::vlog<crow::LogLevel::Warning, Args...>(
141             std::move(format), std::forward<Args>(args)..., loc);
142     }
143 };
144 
145 template <typename... Args>
146 struct BMCWEB_LOG_INFO
147 {
148     // NOLINTNEXTLINE(google-explicit-constructor)
149     BMCWEB_LOG_INFO(std::format_string<Args...> format, Args&&... args,
150                     const std::source_location& loc =
151                         std::source_location::current()) noexcept
152     {
153         crow::vlog<crow::LogLevel::Info, Args...>(
154             std::move(format), std::forward<Args>(args)..., loc);
155     }
156 };
157 
158 template <typename... Args>
159 struct BMCWEB_LOG_DEBUG
160 {
161     // NOLINTNEXTLINE(google-explicit-constructor)
162     BMCWEB_LOG_DEBUG(std::format_string<Args...> format, Args&&... args,
163                      const std::source_location& loc =
164                          std::source_location::current()) noexcept
165     {
166         crow::vlog<crow::LogLevel::Debug, Args...>(
167             std::move(format), std::forward<Args>(args)..., loc);
168     }
169 };
170 
171 template <typename... Args>
172 BMCWEB_LOG_CRITICAL(std::format_string<Args...>, Args&&...)
173     -> BMCWEB_LOG_CRITICAL<Args...>;
174 
175 template <typename... Args>
176 BMCWEB_LOG_ERROR(std::format_string<Args...>, Args&&...)
177     -> BMCWEB_LOG_ERROR<Args...>;
178 
179 template <typename... Args>
180 BMCWEB_LOG_WARNING(std::format_string<Args...>, Args&&...)
181     -> BMCWEB_LOG_WARNING<Args...>;
182 
183 template <typename... Args>
184 BMCWEB_LOG_INFO(std::format_string<Args...>, Args&&...)
185     -> BMCWEB_LOG_INFO<Args...>;
186 
187 template <typename... Args>
188 BMCWEB_LOG_DEBUG(std::format_string<Args...>, Args&&...)
189     -> BMCWEB_LOG_DEBUG<Args...>;
190