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   systemd is free software; you can redistribute it and/or modify it
  10   under the terms of the GNU Lesser General Public License as published by
  11   the Free Software Foundation; either version 2.1 of the License, or
  12   (at your option) any later version.
  13
  14   systemd is distributed in the hope that it will be useful, but
  15   WITHOUT ANY WARRANTY; without even the implied warranty of
  16   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  17   Lesser General Public License for more details.
  18
  19   You should have received a copy of the GNU Lesser General Public License
  20   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  21 ***/
  22
  23 #include <stdarg.h>
  24 #include <stdbool.h>
  25 #include <stdlib.h>
  26 #include <syslog.h>
  27
  28 #include "macro.h"
  29
  30 /* Some structures we reference but don't want to pull in headers for */
  31 struct iovec;
  32 struct signalfd_siginfo;
  33
  34 typedef enum LogRealm {
  35         LOG_REALM_SYSTEMD,
  36         LOG_REALM_UDEV,
  37         _LOG_REALM_MAX,
  38 } LogRealm;
  39
  40 #ifndef LOG_REALM
  41 #  define LOG_REALM LOG_REALM_SYSTEMD
  42 #endif
  43
  44 typedef enum LogTarget{
  45         LOG_TARGET_CONSOLE,
  46         LOG_TARGET_CONSOLE_PREFIXED,
  47         LOG_TARGET_KMSG,
  48         LOG_TARGET_JOURNAL,
  49         LOG_TARGET_JOURNAL_OR_KMSG,
  50         LOG_TARGET_SYSLOG,
  51         LOG_TARGET_SYSLOG_OR_KMSG,
  52         LOG_TARGET_AUTO, /* console if stderr is tty, JOURNAL_OR_KMSG otherwise */
  53         LOG_TARGET_NULL,
  54         _LOG_TARGET_MAX,
  55         _LOG_TARGET_INVALID = -1
  56 } LogTarget;
  57
  58 #define LOG_REALM_PLUS_LEVEL(realm, level)      \
  59         ((realm) << 10 | (level))
  60 #define LOG_REALM_REMOVE_LEVEL(realm_level)     \
  61         ((realm_level >> 10))
  62
  63 void log_set_target(LogTarget target);
  64 void log_set_max_level_realm(LogRealm realm, int level);
  65 #define log_set_max_level(level)                \
  66         log_set_max_level_realm(LOG_REALM, (level))
  67
  68 void log_set_facility(int facility);
  69
  70 int log_set_target_from_string(const char *e);
  71 int log_set_max_level_from_string_realm(LogRealm realm, const char *e);
  72 #define log_set_max_level_from_string(e)        \
  73         log_set_max_level_from_string_realm(LOG_REALM, (e))
  74
  75 void log_show_color(bool b);
  76 bool log_get_show_color(void) _pure_;
  77 void log_show_location(bool b);
  78 bool log_get_show_location(void) _pure_;
  79
  80 int log_show_color_from_string(const char *e);
  81 int log_show_location_from_string(const char *e);
  82
  83 LogTarget log_get_target(void) _pure_;
  84 int log_get_max_level_realm(LogRealm realm) _pure_;
  85 #define log_get_max_level()                     \
  86         log_get_max_level_realm(LOG_REALM)
  87
  88 /* Functions below that open and close logs or configure logging based on the
  89  * environment should not be called from library code — this is always a job
  90  * for the application itself.
  91  */
  92
  93 int log_open(void);
  94 void log_close(void);
  95 void log_forget_fds(void);
  96
  97 void log_close_syslog(void);
  98 void log_close_journal(void);
  99 void log_close_kmsg(void);
 100 void log_close_console(void);
 101
 102 void log_parse_environment_realm(LogRealm realm);
 103 #define log_parse_environment() \
 104         log_parse_environment_realm(LOG_REALM)
 105
 106 int log_dispatch_internal(
 107                 int level,
 108                 int error,
 109                 const char *file,
 110                 int line,
 111                 const char *func,
 112                 const char *object_field,
 113                 const char *object,
 114                 const char *extra,
 115                 const char *extra_field,
 116                 char *buffer);
 117
 118 int log_internal_realm(
 119                 int level,
 120                 int error,
 121                 const char *file,
 122                 int line,
 123                 const char *func,
 124                 const char *format, ...) _printf_(6,7);
 125 #define log_internal(level, ...) \
 126         log_internal_realm(LOG_REALM_PLUS_LEVEL(LOG_REALM, (level)), __VA_ARGS__)
 127
 128 int log_internalv_realm(
 129                 int level,
 130                 int error,
 131                 const char *file,
 132                 int line,
 133                 const char *func,
 134                 const char *format,
 135                 va_list ap) _printf_(6,0);
 136 #define log_internalv(level, ...) \
 137         log_internalv_realm(LOG_REALM_PLUS_LEVEL(LOG_REALM, (level)), __VA_ARGS__)
 138
 139 /* Realm is fixed to LOG_REALM_SYSTEMD for those */
 140 int log_object_internal(
 141                 int level,
 142                 int error,
 143                 const char *file,
 144                 int line,
 145                 const char *func,
 146                 const char *object_field,
 147                 const char *object,
 148                 const char *extra_field,
 149                 const char *extra,
 150                 const char *format, ...) _printf_(10,11);
 151
 152 int log_object_internalv(
 153                 int level,
 154                 int error,
 155                 const char *file,
 156                 int line,
 157                 const char *func,
 158                 const char *object_field,
 159                 const char *object,
 160                 const char *extra_field,
 161                 const char *extra,
 162                 const char *format,
 163                 va_list ap) _printf_(10,0);
 164
 165 int log_struct_internal(
 166                 int level,
 167                 int error,
 168                 const char *file,
 169                 int line,
 170                 const char *func,
 171                 const char *format, ...) _printf_(6,0) _sentinel_;
 172
 173 int log_oom_internal(
 174                 LogRealm realm,
 175                 const char *file,
 176                 int line,
 177                 const char *func);
 178
 179 int log_format_iovec(
 180                 struct iovec *iovec,
 181                 size_t iovec_len,
 182                 size_t *n,
 183                 bool newline_separator,
 184                 int error,
 185                 const char *format,
 186                 va_list ap) _printf_(6, 0);
 187
 188 int log_struct_iovec_internal(
 189                 int level,
 190                 int error,
 191                 const char *file,
 192                 int line,
 193                 const char *func,
 194                 const struct iovec *input_iovec,
 195                 size_t n_input_iovec);
 196
 197 /* This modifies the buffer passed! */
 198 int log_dump_internal(
 199                 int level,
 200                 int error,
 201                 const char *file,
 202                 int line,
 203                 const char *func,
 204                 char *buffer);
 205
 206 /* Logging for various assertions */
 207 noreturn void log_assert_failed_realm(
 208                 LogRealm realm,
 209                 const char *text,
 210                 const char *file,
 211                 int line,
 212                 const char *func);
 213 #define log_assert_failed(text, ...) \
 214         log_assert_failed_realm(LOG_REALM, (text), __VA_ARGS__)
 215
 216 noreturn void log_assert_failed_unreachable_realm(
 217                 LogRealm realm,
 218                 const char *text,
 219                 const char *file,
 220                 int line,
 221                 const char *func);
 222 #define log_assert_failed_unreachable(text, ...) \
 223         log_assert_failed_unreachable_realm(LOG_REALM, (text), __VA_ARGS__)
 224
 225 void log_assert_failed_return_realm(
 226                 LogRealm realm,
 227                 const char *text,
 228                 const char *file,
 229                 int line,
 230                 const char *func);
 231 #define log_assert_failed_return(text, ...) \
 232         log_assert_failed_return_realm(LOG_REALM, (text), __VA_ARGS__)
 233
 234 #define log_dispatch(level, error, buffer)                              \
 235         log_dispatch_internal(level, error, __FILE__, __LINE__, __func__, NULL, NULL, NULL, NULL, buffer)
 236
 237 /* Logging with level */
 238 #define log_full_errno_realm(realm, level, error, ...)                  \
 239         ({                                                              \
 240                 int _level = (level), _e = (error), _realm = (realm);   \
 241                 (log_get_max_level_realm(_realm) >= LOG_PRI(_level))   \
 242                         ? log_internal_realm(LOG_REALM_PLUS_LEVEL(_realm, _level), _e, \
 243                                              __FILE__, __LINE__, __func__, __VA_ARGS__) \
 244                         : -abs(_e);                                     \
 245         })
 246
 247 #define log_full_errno(level, error, ...)                               \
 248         log_full_errno_realm(LOG_REALM, (level), (error), __VA_ARGS__)
 249
 250 #define log_full(level, ...) log_full_errno((level), 0, __VA_ARGS__)
 251
 252 int log_emergency_level(void);
 253
 254 /* Normal logging */
 255 #define log_debug(...)     log_full(LOG_DEBUG,   __VA_ARGS__)
 256 #define log_info(...)      log_full(LOG_INFO,    __VA_ARGS__)
 257 #define log_notice(...)    log_full(LOG_NOTICE,  __VA_ARGS__)
 258 #define log_warning(...)   log_full(LOG_WARNING, __VA_ARGS__)
 259 #define log_error(...)     log_full(LOG_ERR,     __VA_ARGS__)
 260 #define log_emergency(...) log_full(log_emergency_level(), __VA_ARGS__)
 261
 262 /* Logging triggered by an errno-like error */
 263 #define log_debug_errno(error, ...)     log_full_errno(LOG_DEBUG,   error, __VA_ARGS__)
 264 #define log_info_errno(error, ...)      log_full_errno(LOG_INFO,    error, __VA_ARGS__)
 265 #define log_notice_errno(error, ...)    log_full_errno(LOG_NOTICE,  error, __VA_ARGS__)
 266 #define log_warning_errno(error, ...)   log_full_errno(LOG_WARNING, error, __VA_ARGS__)
 267 #define log_error_errno(error, ...)     log_full_errno(LOG_ERR,     error, __VA_ARGS__)
 268 #define log_emergency_errno(error, ...) log_full_errno(log_emergency_level(), error, __VA_ARGS__)
 269
 270 #ifdef LOG_TRACE
 271 #  define log_trace(...) log_debug(__VA_ARGS__)
 272 #else
 273 #  define log_trace(...) do {} while (0)
 274 #endif
 275
 276 /* Structured logging */
 277 #define log_struct_errno(level, error, ...) \
 278         log_struct_internal(LOG_REALM_PLUS_LEVEL(LOG_REALM, level), \
 279                             error, __FILE__, __LINE__, __func__, __VA_ARGS__)
 280 #define log_struct(level, ...) log_struct_errno(level, 0, __VA_ARGS__)
 281
 282 #define log_struct_iovec_errno(level, error, iovec, n_iovec)            \
 283         log_struct_iovec_internal(LOG_REALM_PLUS_LEVEL(LOG_REALM, level), \
 284                                   error, __FILE__, __LINE__, __func__, iovec, n_iovec)
 285 #define log_struct_iovec(level, iovec, n_iovec) log_struct_iovec_errno(level, 0, iovec, n_iovec)
 286
 287 /* This modifies the buffer passed! */
 288 #define log_dump(level, buffer) \
 289         log_dump_internal(LOG_REALM_PLUS_LEVEL(LOG_REALM, level), \
 290                           0, __FILE__, __LINE__, __func__, buffer)
 291
 292 #define log_oom() log_oom_internal(LOG_REALM, __FILE__, __LINE__, __func__)
 293
 294 bool log_on_console(void) _pure_;
 295
 296 const char *log_target_to_string(LogTarget target) _const_;
 297 LogTarget log_target_from_string(const char *s) _pure_;
 298
 299 /* Helper to prepare various field for structured logging */
 300 #define LOG_MESSAGE(fmt, ...) "MESSAGE=" fmt, ##__VA_ARGS__
 301
 302 void log_received_signal(int level, const struct signalfd_siginfo *si);
 303
 304 /* If turned on, any requests for a log target involving "syslog" will be implicitly upgraded to the equivalent journal target */
 305 void log_set_upgrade_syslog_to_journal(bool b);
 306
 307 /* If turned on, and log_open() is called, we'll not use STDERR_FILENO for logging ever, but rather open /dev/console */
 308 void log_set_always_reopen_console(bool b);
 309
 310 /* If turned on, we'll open the log stream implicitly if needed on each individual log call. This is normally not
 311  * desired as we want to reuse our logging streams. It is useful however  */
 312 void log_set_open_when_needed(bool b);
 313
 314 /* 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
 315  * stderr, the console or kmsg */
 316 void log_set_prohibit_ipc(bool b);
 317
 318 int log_syntax_internal(
 319                 const char *unit,
 320                 int level,
 321                 const char *config_file,
 322                 unsigned config_line,
 323                 int error,
 324                 const char *file,
 325                 int line,
 326                 const char *func,
 327                 const char *format, ...) _printf_(9, 10);
 328
 329 int log_syntax_invalid_utf8_internal(
 330                 const char *unit,
 331                 int level,
 332                 const char *config_file,
 333                 unsigned config_line,
 334                 const char *file,
 335                 int line,
 336                 const char *func,
 337                 const char *rvalue);
 338
 339 #define log_syntax(unit, level, config_file, config_line, error, ...)   \
 340         ({                                                              \
 341                 int _level = (level), _e = (error);                     \
 342                 (log_get_max_level() >= LOG_PRI(_level))                \
 343                         ? log_syntax_internal(unit, _level, config_file, config_line, _e, __FILE__, __LINE__, __func__, __VA_ARGS__) \
 344                         : -abs(_e);                                     \
 345         })
 346
 347 #define log_syntax_invalid_utf8(unit, level, config_file, config_line, rvalue) \
 348         ({                                                              \
 349                 int _level = (level);                                   \
 350                 (log_get_max_level() >= LOG_PRI(_level))                \
 351                         ? log_syntax_invalid_utf8_internal(unit, _level, config_file, config_line, __FILE__, __LINE__, __func__, rvalue) \
 352                         : -EINVAL;                                      \
 353         })
 354
 355 #define DEBUG_LOGGING _unlikely_(log_get_max_level() >= LOG_DEBUG)