src/basic/log.h

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2 #pragma once
   3
   4 /***
   5   Copyright 2010 Lennart Poettering
   6 ***/
   7
   8 #include <stdarg.h>
   9 #include <stdbool.h>
  10 #include <stdlib.h>
  11 #include <syslog.h>
  12
  13 #include "macro.h"
  14
  15 /* Some structures we reference but don't want to pull in headers for */
  16 struct iovec;
  17 struct signalfd_siginfo;
  18
  19 typedef enum LogRealm {
  20         LOG_REALM_SYSTEMD,
  21         LOG_REALM_UDEV,
  22         _LOG_REALM_MAX,
  23 } LogRealm;
  24
  25 #ifndef LOG_REALM
  26 #  define LOG_REALM LOG_REALM_SYSTEMD
  27 #endif
  28
  29 typedef enum LogTarget{
  30         LOG_TARGET_CONSOLE,
  31         LOG_TARGET_CONSOLE_PREFIXED,
  32         LOG_TARGET_KMSG,
  33         LOG_TARGET_JOURNAL,
  34         LOG_TARGET_JOURNAL_OR_KMSG,
  35         LOG_TARGET_SYSLOG,
  36         LOG_TARGET_SYSLOG_OR_KMSG,
  37         LOG_TARGET_AUTO, /* console if stderr is tty, JOURNAL_OR_KMSG otherwise */
  38         LOG_TARGET_NULL,
  39         _LOG_TARGET_MAX,
  40         _LOG_TARGET_INVALID = -1
  41 } LogTarget;
  42
  43 #define LOG_REALM_PLUS_LEVEL(realm, level)      \
  44         ((realm) << 10 | (level))
  45 #define LOG_REALM_REMOVE_LEVEL(realm_level)     \
  46         ((realm_level >> 10))
  47
  48 void log_set_target(LogTarget target);
  49 void log_set_max_level_realm(LogRealm realm, int level);
  50 #define log_set_max_level(level)                \
  51         log_set_max_level_realm(LOG_REALM, (level))
  52
  53 void log_set_facility(int facility);
  54
  55 int log_set_target_from_string(const char *e);
  56 int log_set_max_level_from_string_realm(LogRealm realm, const char *e);
  57 #define log_set_max_level_from_string(e)        \
  58         log_set_max_level_from_string_realm(LOG_REALM, (e))
  59
  60 void log_show_color(bool b);
  61 bool log_get_show_color(void) _pure_;
  62 void log_show_location(bool b);
  63 bool log_get_show_location(void) _pure_;
  64
  65 int log_show_color_from_string(const char *e);
  66 int log_show_location_from_string(const char *e);
  67
  68 LogTarget log_get_target(void) _pure_;
  69 int log_get_max_level_realm(LogRealm realm) _pure_;
  70 #define log_get_max_level()                     \
  71         log_get_max_level_realm(LOG_REALM)
  72
  73 /* Functions below that open and close logs or configure logging based on the
  74  * environment should not be called from library code — this is always a job
  75  * for the application itself.
  76  */
  77
  78 int log_open(void);
  79 void log_close(void);
  80 void log_forget_fds(void);
  81
  82 void log_parse_environment_realm(LogRealm realm);
  83 #define log_parse_environment() \
  84         log_parse_environment_realm(LOG_REALM)
  85
  86 int log_dispatch_internal(
  87                 int level,
  88                 int error,
  89                 const char *file,
  90                 int line,
  91                 const char *func,
  92                 const char *object_field,
  93                 const char *object,
  94                 const char *extra,
  95                 const char *extra_field,
  96                 char *buffer);
  97
  98 int log_internal_realm(
  99                 int level,
 100                 int error,
 101                 const char *file,
 102                 int line,
 103                 const char *func,
 104                 const char *format, ...) _printf_(6,7);
 105 #define log_internal(level, ...) \
 106         log_internal_realm(LOG_REALM_PLUS_LEVEL(LOG_REALM, (level)), __VA_ARGS__)
 107
 108 int log_internalv_realm(
 109                 int level,
 110                 int error,
 111                 const char *file,
 112                 int line,
 113                 const char *func,
 114                 const char *format,
 115                 va_list ap) _printf_(6,0);
 116 #define log_internalv(level, ...) \
 117         log_internalv_realm(LOG_REALM_PLUS_LEVEL(LOG_REALM, (level)), __VA_ARGS__)
 118
 119 /* Realm is fixed to LOG_REALM_SYSTEMD for those */
 120 int log_object_internal(
 121                 int level,
 122                 int error,
 123                 const char *file,
 124                 int line,
 125                 const char *func,
 126                 const char *object_field,
 127                 const char *object,
 128                 const char *extra_field,
 129                 const char *extra,
 130                 const char *format, ...) _printf_(10,11);
 131
 132 int log_struct_internal(
 133                 int level,
 134                 int error,
 135                 const char *file,
 136                 int line,
 137                 const char *func,
 138                 const char *format, ...) _printf_(6,0) _sentinel_;
 139
 140 int log_oom_internal(
 141                 LogRealm realm,
 142                 const char *file,
 143                 int line,
 144                 const char *func);
 145
 146 int log_format_iovec(
 147                 struct iovec *iovec,
 148                 size_t iovec_len,
 149                 size_t *n,
 150                 bool newline_separator,
 151                 int error,
 152                 const char *format,
 153                 va_list ap) _printf_(6, 0);
 154
 155 int log_struct_iovec_internal(
 156                 int level,
 157                 int error,
 158                 const char *file,
 159                 int line,
 160                 const char *func,
 161                 const struct iovec *input_iovec,
 162                 size_t n_input_iovec);
 163
 164 /* This modifies the buffer passed! */
 165 int log_dump_internal(
 166                 int level,
 167                 int error,
 168                 const char *file,
 169                 int line,
 170                 const char *func,
 171                 char *buffer);
 172
 173 /* Logging for various assertions */
 174 _noreturn_ void log_assert_failed_realm(
 175                 LogRealm realm,
 176                 const char *text,
 177                 const char *file,
 178                 int line,
 179                 const char *func);
 180 #define log_assert_failed(text, ...) \
 181         log_assert_failed_realm(LOG_REALM, (text), __VA_ARGS__)
 182
 183 _noreturn_ void log_assert_failed_unreachable_realm(
 184                 LogRealm realm,
 185                 const char *text,
 186                 const char *file,
 187                 int line,
 188                 const char *func);
 189 #define log_assert_failed_unreachable(text, ...) \
 190         log_assert_failed_unreachable_realm(LOG_REALM, (text), __VA_ARGS__)
 191
 192 void log_assert_failed_return_realm(
 193                 LogRealm realm,
 194                 const char *text,
 195                 const char *file,
 196                 int line,
 197                 const char *func);
 198 #define log_assert_failed_return(text, ...) \
 199         log_assert_failed_return_realm(LOG_REALM, (text), __VA_ARGS__)
 200
 201 #define log_dispatch(level, error, buffer)                              \
 202         log_dispatch_internal(level, error, __FILE__, __LINE__, __func__, NULL, NULL, NULL, NULL, buffer)
 203
 204 /* Logging with level */
 205 #define log_full_errno_realm(realm, level, error, ...)                  \
 206         ({                                                              \
 207                 int _level = (level), _e = (error), _realm = (realm);   \
 208                 (log_get_max_level_realm(_realm) >= LOG_PRI(_level))   \
 209                         ? log_internal_realm(LOG_REALM_PLUS_LEVEL(_realm, _level), _e, \
 210                                              __FILE__, __LINE__, __func__, __VA_ARGS__) \
 211                         : -abs(_e);                                     \
 212         })
 213
 214 #define log_full_errno(level, error, ...)                               \
 215         log_full_errno_realm(LOG_REALM, (level), (error), __VA_ARGS__)
 216
 217 #define log_full(level, ...) log_full_errno((level), 0, __VA_ARGS__)
 218
 219 int log_emergency_level(void);
 220
 221 /* Normal logging */
 222 #define log_debug(...)     log_full(LOG_DEBUG,   __VA_ARGS__)
 223 #define log_info(...)      log_full(LOG_INFO,    __VA_ARGS__)
 224 #define log_notice(...)    log_full(LOG_NOTICE,  __VA_ARGS__)
 225 #define log_warning(...)   log_full(LOG_WARNING, __VA_ARGS__)
 226 #define log_error(...)     log_full(LOG_ERR,     __VA_ARGS__)
 227 #define log_emergency(...) log_full(log_emergency_level(), __VA_ARGS__)
 228
 229 /* Logging triggered by an errno-like error */
 230 #define log_debug_errno(error, ...)     log_full_errno(LOG_DEBUG,   error, __VA_ARGS__)
 231 #define log_info_errno(error, ...)      log_full_errno(LOG_INFO,    error, __VA_ARGS__)
 232 #define log_notice_errno(error, ...)    log_full_errno(LOG_NOTICE,  error, __VA_ARGS__)
 233 #define log_warning_errno(error, ...)   log_full_errno(LOG_WARNING, error, __VA_ARGS__)
 234 #define log_error_errno(error, ...)     log_full_errno(LOG_ERR,     error, __VA_ARGS__)
 235 #define log_emergency_errno(error, ...) log_full_errno(log_emergency_level(), error, __VA_ARGS__)
 236
 237 #ifdef LOG_TRACE
 238 #  define log_trace(...) log_debug(__VA_ARGS__)
 239 #else
 240 #  define log_trace(...) do {} while (0)
 241 #endif
 242
 243 /* Structured logging */
 244 #define log_struct_errno(level, error, ...) \
 245         log_struct_internal(LOG_REALM_PLUS_LEVEL(LOG_REALM, level), \
 246                             error, __FILE__, __LINE__, __func__, __VA_ARGS__, NULL)
 247 #define log_struct(level, ...) log_struct_errno(level, 0, __VA_ARGS__)
 248
 249 #define log_struct_iovec_errno(level, error, iovec, n_iovec)            \
 250         log_struct_iovec_internal(LOG_REALM_PLUS_LEVEL(LOG_REALM, level), \
 251                                   error, __FILE__, __LINE__, __func__, iovec, n_iovec)
 252 #define log_struct_iovec(level, iovec, n_iovec) log_struct_iovec_errno(level, 0, iovec, n_iovec)
 253
 254 /* This modifies the buffer passed! */
 255 #define log_dump(level, buffer) \
 256         log_dump_internal(LOG_REALM_PLUS_LEVEL(LOG_REALM, level), \
 257                           0, __FILE__, __LINE__, __func__, buffer)
 258
 259 #define log_oom() log_oom_internal(LOG_REALM, __FILE__, __LINE__, __func__)
 260
 261 bool log_on_console(void) _pure_;
 262
 263 const char *log_target_to_string(LogTarget target) _const_;
 264 LogTarget log_target_from_string(const char *s) _pure_;
 265
 266 /* Helper to prepare various field for structured logging */
 267 #define LOG_MESSAGE(fmt, ...) "MESSAGE=" fmt, ##__VA_ARGS__
 268
 269 void log_received_signal(int level, const struct signalfd_siginfo *si);
 270
 271 /* If turned on, any requests for a log target involving "syslog" will be implicitly upgraded to the equivalent journal target */
 272 void log_set_upgrade_syslog_to_journal(bool b);
 273
 274 /* If turned on, and log_open() is called, we'll not use STDERR_FILENO for logging ever, but rather open /dev/console */
 275 void log_set_always_reopen_console(bool b);
 276
 277 /* If turned on, we'll open the log stream implicitly if needed on each individual log call. This is normally not
 278  * desired as we want to reuse our logging streams. It is useful however  */
 279 void log_set_open_when_needed(bool b);
 280
 281 /* If turned on, then we'll never use IPC-based logging, i.e. never log to syslog or the journal. We'll only log to
 282  * stderr, the console or kmsg */
 283 void log_set_prohibit_ipc(bool b);
 284
 285 int log_dup_console(void);
 286
 287 int log_syntax_internal(
 288                 const char *unit,
 289                 int level,
 290                 const char *config_file,
 291                 unsigned config_line,
 292                 int error,
 293                 const char *file,
 294                 int line,
 295                 const char *func,
 296                 const char *format, ...) _printf_(9, 10);
 297
 298 int log_syntax_invalid_utf8_internal(
 299                 const char *unit,
 300                 int level,
 301                 const char *config_file,
 302                 unsigned config_line,
 303                 const char *file,
 304                 int line,
 305                 const char *func,
 306                 const char *rvalue);
 307
 308 #define log_syntax(unit, level, config_file, config_line, error, ...)   \
 309         ({                                                              \
 310                 int _level = (level), _e = (error);                     \
 311                 (log_get_max_level() >= LOG_PRI(_level))                \
 312                         ? log_syntax_internal(unit, _level, config_file, config_line, _e, __FILE__, __LINE__, __func__, __VA_ARGS__) \
 313                         : -abs(_e);                                     \
 314         })
 315
 316 #define log_syntax_invalid_utf8(unit, level, config_file, config_line, rvalue) \
 317         ({                                                              \
 318                 int _level = (level);                                   \
 319                 (log_get_max_level() >= LOG_PRI(_level))                \
 320                         ? log_syntax_invalid_utf8_internal(unit, _level, config_file, config_line, __FILE__, __LINE__, __func__, rvalue) \
 321                         : -EINVAL;                                      \
 322         })
 323
 324 #define DEBUG_LOGGING _unlikely_(log_get_max_level() >= LOG_DEBUG)