src/basic/log.h

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2 #pragma once
   3
   4 /***
   5   This file is part of systemd.
   6
   7   Copyright 2010 Lennart Poettering
   8 ***/
   9
  10 #include <stdarg.h>
  11 #include <stdbool.h>
  12 #include <stdlib.h>
  13 #include <syslog.h>
  14
  15 #include "macro.h"
  16
  17 /* Some structures we reference but don't want to pull in headers for */
  18 struct iovec;
  19 struct signalfd_siginfo;
  20
  21 typedef enum LogRealm {
  22         LOG_REALM_SYSTEMD,
  23         LOG_REALM_UDEV,
  24         _LOG_REALM_MAX,
  25 } LogRealm;
  26
  27 #ifndef LOG_REALM
  28 #  define LOG_REALM LOG_REALM_SYSTEMD
  29 #endif
  30
  31 typedef enum LogTarget{
  32         LOG_TARGET_CONSOLE,
  33         LOG_TARGET_CONSOLE_PREFIXED,
  34         LOG_TARGET_KMSG,
  35         LOG_TARGET_JOURNAL,
  36         LOG_TARGET_JOURNAL_OR_KMSG,
  37         LOG_TARGET_SYSLOG,
  38         LOG_TARGET_SYSLOG_OR_KMSG,
  39         LOG_TARGET_AUTO, /* console if stderr is tty, JOURNAL_OR_KMSG otherwise */
  40         LOG_TARGET_NULL,
  41         _LOG_TARGET_MAX,
  42         _LOG_TARGET_INVALID = -1
  43 } LogTarget;
  44
  45 #define LOG_REALM_PLUS_LEVEL(realm, level)      \
  46         ((realm) << 10 | (level))
  47 #define LOG_REALM_REMOVE_LEVEL(realm_level)     \
  48         ((realm_level >> 10))
  49
  50 void log_set_target(LogTarget target);
  51 void log_set_max_level_realm(LogRealm realm, int level);
  52 #define log_set_max_level(level)                \
  53         log_set_max_level_realm(LOG_REALM, (level))
  54
  55 void log_set_facility(int facility);
  56
  57 int log_set_target_from_string(const char *e);
  58 int log_set_max_level_from_string_realm(LogRealm realm, const char *e);
  59 #define log_set_max_level_from_string(e)        \
  60         log_set_max_level_from_string_realm(LOG_REALM, (e))
  61
  62 void log_show_color(bool b);
  63 bool log_get_show_color(void) _pure_;
  64 void log_show_location(bool b);
  65 bool log_get_show_location(void) _pure_;
  66
  67 int log_show_color_from_string(const char *e);
  68 int log_show_location_from_string(const char *e);
  69
  70 LogTarget log_get_target(void) _pure_;
  71 int log_get_max_level_realm(LogRealm realm) _pure_;
  72 #define log_get_max_level()                     \
  73         log_get_max_level_realm(LOG_REALM)
  74
  75 /* Functions below that open and close logs or configure logging based on the
  76  * environment should not be called from library code — this is always a job
  77  * for the application itself.
  78  */
  79
  80 int log_open(void);
  81 void log_close(void);
  82 void log_forget_fds(void);
  83
  84 void log_parse_environment_realm(LogRealm realm);
  85 #define log_parse_environment() \
  86         log_parse_environment_realm(LOG_REALM)
  87
  88 int log_dispatch_internal(
  89                 int level,
  90                 int error,
  91                 const char *file,
  92                 int line,
  93                 const char *func,
  94                 const char *object_field,
  95                 const char *object,
  96                 const char *extra,
  97                 const char *extra_field,
  98                 char *buffer);
  99
 100 int log_internal_realm(
 101                 int level,
 102                 int error,
 103                 const char *file,
 104                 int line,
 105                 const char *func,
 106                 const char *format, ...) _printf_(6,7);
 107 #define log_internal(level, ...) \
 108         log_internal_realm(LOG_REALM_PLUS_LEVEL(LOG_REALM, (level)), __VA_ARGS__)
 109
 110 int log_internalv_realm(
 111                 int level,
 112                 int error,
 113                 const char *file,
 114                 int line,
 115                 const char *func,
 116                 const char *format,
 117                 va_list ap) _printf_(6,0);
 118 #define log_internalv(level, ...) \
 119         log_internalv_realm(LOG_REALM_PLUS_LEVEL(LOG_REALM, (level)), __VA_ARGS__)
 120
 121 /* Realm is fixed to LOG_REALM_SYSTEMD for those */
 122 int log_object_internal(
 123                 int level,
 124                 int error,
 125                 const char *file,
 126                 int line,
 127                 const char *func,
 128                 const char *object_field,
 129                 const char *object,
 130                 const char *extra_field,
 131                 const char *extra,
 132                 const char *format, ...) _printf_(10,11);
 133
 134 int log_struct_internal(
 135                 int level,
 136                 int error,
 137                 const char *file,
 138                 int line,
 139                 const char *func,
 140                 const char *format, ...) _printf_(6,0) _sentinel_;
 141
 142 int log_oom_internal(
 143                 LogRealm realm,
 144                 const char *file,
 145                 int line,
 146                 const char *func);
 147
 148 int log_format_iovec(
 149                 struct iovec *iovec,
 150                 size_t iovec_len,
 151                 size_t *n,
 152                 bool newline_separator,
 153                 int error,
 154                 const char *format,
 155                 va_list ap) _printf_(6, 0);
 156
 157 int log_struct_iovec_internal(
 158                 int level,
 159                 int error,
 160                 const char *file,
 161                 int line,
 162                 const char *func,
 163                 const struct iovec *input_iovec,
 164                 size_t n_input_iovec);
 165
 166 /* This modifies the buffer passed! */
 167 int log_dump_internal(
 168                 int level,
 169                 int error,
 170                 const char *file,
 171                 int line,
 172                 const char *func,
 173                 char *buffer);
 174
 175 /* Logging for various assertions */
 176 _noreturn_ void log_assert_failed_realm(
 177                 LogRealm realm,
 178                 const char *text,
 179                 const char *file,
 180                 int line,
 181                 const char *func);
 182 #define log_assert_failed(text, ...) \
 183         log_assert_failed_realm(LOG_REALM, (text), __VA_ARGS__)
 184
 185 _noreturn_ void log_assert_failed_unreachable_realm(
 186                 LogRealm realm,
 187                 const char *text,
 188                 const char *file,
 189                 int line,
 190                 const char *func);
 191 #define log_assert_failed_unreachable(text, ...) \
 192         log_assert_failed_unreachable_realm(LOG_REALM, (text), __VA_ARGS__)
 193
 194 void log_assert_failed_return_realm(
 195                 LogRealm realm,
 196                 const char *text,
 197                 const char *file,
 198                 int line,
 199                 const char *func);
 200 #define log_assert_failed_return(text, ...) \
 201         log_assert_failed_return_realm(LOG_REALM, (text), __VA_ARGS__)
 202
 203 #define log_dispatch(level, error, buffer)                              \
 204         log_dispatch_internal(level, error, __FILE__, __LINE__, __func__, NULL, NULL, NULL, NULL, buffer)
 205
 206 /* Logging with level */
 207 #define log_full_errno_realm(realm, level, error, ...)                  \
 208         ({                                                              \
 209                 int _level = (level), _e = (error), _realm = (realm);   \
 210                 (log_get_max_level_realm(_realm) >= LOG_PRI(_level))   \
 211                         ? log_internal_realm(LOG_REALM_PLUS_LEVEL(_realm, _level), _e, \
 212                                              __FILE__, __LINE__, __func__, __VA_ARGS__) \
 213                         : -abs(_e);                                     \
 214         })
 215
 216 #define log_full_errno(level, error, ...)                               \
 217         log_full_errno_realm(LOG_REALM, (level), (error), __VA_ARGS__)
 218
 219 #define log_full(level, ...) log_full_errno((level), 0, __VA_ARGS__)
 220
 221 int log_emergency_level(void);
 222
 223 /* Normal logging */
 224 #define log_debug(...)     log_full(LOG_DEBUG,   __VA_ARGS__)
 225 #define log_info(...)      log_full(LOG_INFO,    __VA_ARGS__)
 226 #define log_notice(...)    log_full(LOG_NOTICE,  __VA_ARGS__)
 227 #define log_warning(...)   log_full(LOG_WARNING, __VA_ARGS__)
 228 #define log_error(...)     log_full(LOG_ERR,     __VA_ARGS__)
 229 #define log_emergency(...) log_full(log_emergency_level(), __VA_ARGS__)
 230
 231 /* Logging triggered by an errno-like error */
 232 #define log_debug_errno(error, ...)     log_full_errno(LOG_DEBUG,   error, __VA_ARGS__)
 233 #define log_info_errno(error, ...)      log_full_errno(LOG_INFO,    error, __VA_ARGS__)
 234 #define log_notice_errno(error, ...)    log_full_errno(LOG_NOTICE,  error, __VA_ARGS__)
 235 #define log_warning_errno(error, ...)   log_full_errno(LOG_WARNING, error, __VA_ARGS__)
 236 #define log_error_errno(error, ...)     log_full_errno(LOG_ERR,     error, __VA_ARGS__)
 237 #define log_emergency_errno(error, ...) log_full_errno(log_emergency_level(), error, __VA_ARGS__)
 238
 239 #ifdef LOG_TRACE
 240 #  define log_trace(...) log_debug(__VA_ARGS__)
 241 #else
 242 #  define log_trace(...) do {} while (0)
 243 #endif
 244
 245 /* Structured logging */
 246 #define log_struct_errno(level, error, ...) \
 247         log_struct_internal(LOG_REALM_PLUS_LEVEL(LOG_REALM, level), \
 248                             error, __FILE__, __LINE__, __func__, __VA_ARGS__, NULL)
 249 #define log_struct(level, ...) log_struct_errno(level, 0, __VA_ARGS__)
 250
 251 #define log_struct_iovec_errno(level, error, iovec, n_iovec)            \
 252         log_struct_iovec_internal(LOG_REALM_PLUS_LEVEL(LOG_REALM, level), \
 253                                   error, __FILE__, __LINE__, __func__, iovec, n_iovec)
 254 #define log_struct_iovec(level, iovec, n_iovec) log_struct_iovec_errno(level, 0, iovec, n_iovec)
 255
 256 /* This modifies the buffer passed! */
 257 #define log_dump(level, buffer) \
 258         log_dump_internal(LOG_REALM_PLUS_LEVEL(LOG_REALM, level), \
 259                           0, __FILE__, __LINE__, __func__, buffer)
 260
 261 #define log_oom() log_oom_internal(LOG_REALM, __FILE__, __LINE__, __func__)
 262
 263 bool log_on_console(void) _pure_;
 264
 265 const char *log_target_to_string(LogTarget target) _const_;
 266 LogTarget log_target_from_string(const char *s) _pure_;
 267
 268 /* Helper to prepare various field for structured logging */
 269 #define LOG_MESSAGE(fmt, ...) "MESSAGE=" fmt, ##__VA_ARGS__
 270
 271 void log_received_signal(int level, const struct signalfd_siginfo *si);
 272
 273 /* If turned on, any requests for a log target involving "syslog" will be implicitly upgraded to the equivalent journal target */
 274 void log_set_upgrade_syslog_to_journal(bool b);
 275
 276 /* If turned on, and log_open() is called, we'll not use STDERR_FILENO for logging ever, but rather open /dev/console */
 277 void log_set_always_reopen_console(bool b);
 278
 279 /* If turned on, we'll open the log stream implicitly if needed on each individual log call. This is normally not
 280  * desired as we want to reuse our logging streams. It is useful however  */
 281 void log_set_open_when_needed(bool b);
 282
 283 /* 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
 284  * stderr, the console or kmsg */
 285 void log_set_prohibit_ipc(bool b);
 286
 287 int log_dup_console(void);
 288
 289 int log_syntax_internal(
 290                 const char *unit,
 291                 int level,
 292                 const char *config_file,
 293                 unsigned config_line,
 294                 int error,
 295                 const char *file,
 296                 int line,
 297                 const char *func,
 298                 const char *format, ...) _printf_(9, 10);
 299
 300 int log_syntax_invalid_utf8_internal(
 301                 const char *unit,
 302                 int level,
 303                 const char *config_file,
 304                 unsigned config_line,
 305                 const char *file,
 306                 int line,
 307                 const char *func,
 308                 const char *rvalue);
 309
 310 #define log_syntax(unit, level, config_file, config_line, error, ...)   \
 311         ({                                                              \
 312                 int _level = (level), _e = (error);                     \
 313                 (log_get_max_level() >= LOG_PRI(_level))                \
 314                         ? log_syntax_internal(unit, _level, config_file, config_line, _e, __FILE__, __LINE__, __func__, __VA_ARGS__) \
 315                         : -abs(_e);                                     \
 316         })
 317
 318 #define log_syntax_invalid_utf8(unit, level, config_file, config_line, rvalue) \
 319         ({                                                              \
 320                 int _level = (level);                                   \
 321                 (log_get_max_level() >= LOG_PRI(_level))                \
 322                         ? log_syntax_invalid_utf8_internal(unit, _level, config_file, config_line, __FILE__, __LINE__, __func__, rvalue) \
 323                         : -EINVAL;                                      \
 324         })
 325
 326 #define DEBUG_LOGGING _unlikely_(log_get_max_level() >= LOG_DEBUG)