xref: /openbmc/bmcweb/http/logging.hpp (revision 7a16ddc8)
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 {
parsestd::formatter16     constexpr auto parse(std::format_parse_context& ctx)
17     {
18         return ctx.begin();
19     }
formatstd::formatter20     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 
getLogLevelFromName(std::string_view name)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
getBmcwebCurrentLoggingLevel()56 inline crow::LogLevel& getBmcwebCurrentLoggingLevel()
57 {
58     static crow::LogLevel level = getLogLevelFromName(BMCWEB_LOGGING_LEVEL);
59     return level;
60 }
61 
62 struct FormatString
63 {
64     std::string_view str;
65     std::source_location loc;
66 
67     // NOLINTNEXTLINE(google-explicit-constructor)
FormatStringcrow::FormatString68     FormatString(const char* stringIn, const std::source_location& locIn =
69                                            std::source_location::current()) :
70         str(stringIn), loc(locIn)
71     {}
72 };
73 
74 template <typename T>
logPtr(T p)75 const void* logPtr(T p)
76 {
77     static_assert(std::is_pointer<T>::value,
78                   "Can't use logPtr without pointer");
79     return std::bit_cast<const void*>(p);
80 }
81 
82 template <LogLevel level, typename... Args>
vlog(std::format_string<Args...> && format,Args &&...args,const std::source_location & loc)83 inline void vlog(std::format_string<Args...>&& format, Args&&... args,
84                  const std::source_location& loc) noexcept
85 {
86     if (getBmcwebCurrentLoggingLevel() < level)
87     {
88         return;
89     }
90     constexpr size_t stringIndex = static_cast<size_t>(level);
91     static_assert(stringIndex < mapLogLevelFromName.size(),
92                   "Missing string for level");
93     constexpr std::string_view levelString = mapLogLevelFromName[stringIndex];
94     std::string_view filename = loc.file_name();
95     filename = filename.substr(filename.rfind('/'));
96     if (!filename.empty())
97     {
98         filename.remove_prefix(1);
99     }
100     std::string logLocation;
101     try
102     {
103         // TODO, multiple static analysis tools flag that this could potentially
104         // throw Based on the documentation, it shouldn't throw, so long as none
105         // of the formatters throw, so unclear at this point why this try/catch
106         // is required, but add it to silence the static analysis tools.
107         logLocation =
108             std::format("[{} {}:{}] ", levelString, filename, loc.line());
109         logLocation +=
110             std::format(std::move(format), std::forward<Args>(args)...);
111     }
112     catch (const std::format_error& /*error*/)
113     {
114         logLocation += "Failed to format";
115         // Nothing more we can do here if logging is broken.
116     }
117     logLocation += '\n';
118     // Intentionally ignore error return.
119     fwrite(logLocation.data(), sizeof(std::string::value_type),
120            logLocation.size(), stdout);
121     fflush(stdout);
122 }
123 } // namespace crow
124 
125 template <typename... Args>
126 struct BMCWEB_LOG_CRITICAL
127 {
128     // NOLINTNEXTLINE(google-explicit-constructor)
BMCWEB_LOG_CRITICALBMCWEB_LOG_CRITICAL129     BMCWEB_LOG_CRITICAL(std::format_string<Args...> format, Args&&... args,
130                         const std::source_location& loc =
131                             std::source_location::current()) noexcept
132     {
133         crow::vlog<crow::LogLevel::Critical, Args...>(
134             std::move(format), std::forward<Args>(args)..., loc);
135     }
136 };
137 
138 template <typename... Args>
139 struct BMCWEB_LOG_ERROR
140 {
141     // NOLINTNEXTLINE(google-explicit-constructor)
BMCWEB_LOG_ERRORBMCWEB_LOG_ERROR142     BMCWEB_LOG_ERROR(std::format_string<Args...> format, Args&&... args,
143                      const std::source_location& loc =
144                          std::source_location::current()) noexcept
145     {
146         crow::vlog<crow::LogLevel::Error, Args...>(
147             std::move(format), std::forward<Args>(args)..., loc);
148     }
149 };
150 
151 template <typename... Args>
152 struct BMCWEB_LOG_WARNING
153 {
154     // NOLINTNEXTLINE(google-explicit-constructor)
BMCWEB_LOG_WARNINGBMCWEB_LOG_WARNING155     BMCWEB_LOG_WARNING(std::format_string<Args...> format, Args&&... args,
156                        const std::source_location& loc =
157                            std::source_location::current()) noexcept
158     {
159         crow::vlog<crow::LogLevel::Warning, Args...>(
160             std::move(format), std::forward<Args>(args)..., loc);
161     }
162 };
163 
164 template <typename... Args>
165 struct BMCWEB_LOG_INFO
166 {
167     // NOLINTNEXTLINE(google-explicit-constructor)
BMCWEB_LOG_INFOBMCWEB_LOG_INFO168     BMCWEB_LOG_INFO(std::format_string<Args...> format, Args&&... args,
169                     const std::source_location& loc =
170                         std::source_location::current()) noexcept
171     {
172         crow::vlog<crow::LogLevel::Info, Args...>(
173             std::move(format), std::forward<Args>(args)..., loc);
174     }
175 };
176 
177 template <typename... Args>
178 struct BMCWEB_LOG_DEBUG
179 {
180     // NOLINTNEXTLINE(google-explicit-constructor)
BMCWEB_LOG_DEBUGBMCWEB_LOG_DEBUG181     BMCWEB_LOG_DEBUG(std::format_string<Args...> format, Args&&... args,
182                      const std::source_location& loc =
183                          std::source_location::current()) noexcept
184     {
185         crow::vlog<crow::LogLevel::Debug, Args...>(
186             std::move(format), std::forward<Args>(args)..., loc);
187     }
188 };
189 
190 template <typename... Args>
191 BMCWEB_LOG_CRITICAL(std::format_string<Args...>,
192                     Args&&...) -> BMCWEB_LOG_CRITICAL<Args...>;
193 
194 template <typename... Args>
195 BMCWEB_LOG_ERROR(std::format_string<Args...>,
196                  Args&&...) -> BMCWEB_LOG_ERROR<Args...>;
197 
198 template <typename... Args>
199 BMCWEB_LOG_WARNING(std::format_string<Args...>,
200                    Args&&...) -> BMCWEB_LOG_WARNING<Args...>;
201 
202 template <typename... Args>
203 BMCWEB_LOG_INFO(std::format_string<Args...>,
204                 Args&&...) -> BMCWEB_LOG_INFO<Args...>;
205 
206 template <typename... Args>
207 BMCWEB_LOG_DEBUG(std::format_string<Args...>,
208                  Args&&...) -> BMCWEB_LOG_DEBUG<Args...>;
209