1 #define SD_JOURNAL_SUPPRESS_LOCATION
2 
3 #include <systemd/sd-journal.h>
4 #include <unistd.h>
5 
6 #include <algorithm>
7 #include <bitset>
8 #include <cstdarg>
9 #include <cstdio>
10 #include <iostream>
11 #include <phosphor-logging/lg2.hpp>
12 #include <vector>
13 
14 namespace lg2::details
15 {
16 /** Convert unsigned to string using format flags. */
17 static std::string value_to_string(uint64_t f, uint64_t v)
18 {
19     switch (f & (hex | bin | dec).value)
20     {
21         // For binary, use bitset<>::to_string.
22         // Treat values without a field-length format flag as 64 bit.
23         case bin.value:
24         {
25             switch (f & (field8 | field16 | field32 | field64).value)
26             {
27                 case field8.value:
28                 {
29                     return "0b" + std::bitset<8>(v).to_string();
30                 }
31                 case field16.value:
32                 {
33                     return "0b" + std::bitset<16>(v).to_string();
34                 }
35                 case field32.value:
36                 {
37                     return "0b" + std::bitset<32>(v).to_string();
38                 }
39                 case field64.value:
40                 default:
41                 {
42                     return "0b" + std::bitset<64>(v).to_string();
43                 }
44             }
45         }
46 
47         // For hex, use the appropriate sprintf.
48         case hex.value:
49         {
50             char value[19];
51             const char* format = nullptr;
52 
53             switch (f & (field8 | field16 | field32 | field64).value)
54             {
55                 case field8.value:
56                 {
57                     format = "0x%02" PRIx64;
58                     break;
59                 }
60 
61                 case field16.value:
62                 {
63                     format = "0x%04" PRIx64;
64                     break;
65                 }
66 
67                 case field32.value:
68                 {
69                     format = "0x%08" PRIx64;
70                     break;
71                 }
72 
73                 case field64.value:
74                 {
75                     format = "0x%016" PRIx64;
76                     break;
77                 }
78 
79                 default:
80                 {
81                     format = "0x%" PRIx64;
82                     break;
83                 }
84             }
85 
86             snprintf(value, sizeof(value), format, v);
87             return value;
88         }
89 
90         // For dec, use the simple to_string.
91         case dec.value:
92         default:
93         {
94             return std::to_string(v);
95         }
96     }
97 }
98 
99 /** Convert signed to string using format flags. */
100 static std::string value_to_string(uint64_t f, int64_t v)
101 {
102     // If hex or bin was requested just use the unsigned formatting
103     // rules. (What should a negative binary number look like otherwise?)
104     if (f & (hex | bin).value)
105     {
106         return value_to_string(f, static_cast<uint64_t>(v));
107     }
108     return std::to_string(v);
109 }
110 
111 /** Convert float to string using format flags. */
112 static std::string value_to_string(uint64_t, double v)
113 {
114     // No format flags supported for floats.
115     return std::to_string(v);
116 }
117 
118 // Positions of various strings in an iovec.
119 static constexpr size_t pos_msg = 0;
120 static constexpr size_t pos_fmtmsg = 1;
121 static constexpr size_t pos_prio = 2;
122 static constexpr size_t pos_file = 3;
123 static constexpr size_t pos_line = 4;
124 static constexpr size_t pos_func = 5;
125 static constexpr size_t static_locs = pos_func + 1;
126 
127 /** No-op output of a message. */
128 static void noop_extra_output(level, const lg2::source_location&,
129                               const std::string&)
130 {
131 }
132 
133 /** std::cerr output of a message. */
134 static void cerr_extra_output(level l, const lg2::source_location& s,
135                               const std::string& m)
136 {
137     std::cerr << s.file_name() << ":" << s.line() << ":" << s.function_name()
138               << "|<" << static_cast<uint64_t>(l) << "> " << m << std::endl;
139 }
140 
141 // Use the cerr output method if we are on a TTY.
142 static auto extra_output_method =
143     isatty(fileno(stderr)) ? cerr_extra_output : noop_extra_output;
144 
145 // Do_log implementation.
146 void do_log(level l, const lg2::source_location& s, const char* m, ...)
147 {
148     using namespace std::string_literals;
149 
150     std::vector<std::string> strings{static_locs};
151 
152     std::string message{m};
153 
154     // Assign all the static fields.
155     strings[pos_fmtmsg] = "LOG2_FMTMSG="s + m;
156     strings[pos_prio] = "PRIORITY="s + std::to_string(static_cast<uint64_t>(l));
157     strings[pos_file] = "CODE_FILE="s + s.file_name();
158     strings[pos_line] = "CODE_LINE="s + std::to_string(s.line());
159     strings[pos_func] = "CODE_FUNC="s + s.function_name();
160 
161     // Handle all the va_list args.
162     std::va_list args;
163     va_start(args, m);
164     while (true)
165     {
166         // Get the header out.
167         auto h_ptr = va_arg(args, const char*);
168         if (h_ptr == nullptr)
169         {
170             break;
171         }
172         std::string h{h_ptr};
173 
174         // Get the format flag.
175         auto f = va_arg(args, uint64_t);
176 
177         // Handle the value depending on which type format flag it has.
178         std::string value = {};
179         switch (f & (signed_val | unsigned_val | str | floating).value)
180         {
181             case signed_val.value:
182             {
183                 auto v = va_arg(args, int64_t);
184                 value = value_to_string(f, v);
185                 break;
186             }
187 
188             case unsigned_val.value:
189             {
190                 auto v = va_arg(args, uint64_t);
191                 value = value_to_string(f, v);
192                 break;
193             }
194 
195             case str.value:
196             {
197                 value = va_arg(args, const char*);
198                 break;
199             }
200 
201             case floating.value:
202             {
203                 auto v = va_arg(args, double);
204                 value = value_to_string(f, v);
205                 break;
206             }
207         }
208 
209         // Create the field for this value.
210         strings.emplace_back(h + '=' + value);
211 
212         // Check for {HEADER} in the message and replace with value.
213         auto h_brace = '{' + h + '}';
214         if (auto start = message.find(h_brace); start != std::string::npos)
215         {
216             message.replace(start, h_brace.size(), value);
217         }
218     }
219     va_end(args);
220 
221     // Add the final message into the strings array.
222     strings[pos_msg] = "MESSAGE="s + message.data();
223 
224     // Trasform strings -> iovec.
225     std::vector<iovec> iov{};
226     std::ranges::transform(strings, std::back_inserter(iov), [](auto& s) {
227         return iovec{s.data(), s.length()};
228     });
229 
230     // Output the iovec.
231     sd_journal_sendv(iov.data(), strings.size());
232     extra_output_method(l, s, message);
233 }
234 
235 } // namespace lg2::details
236