/* SPDX-License-Identifier: LGPL-2.1-or-later */ #pragma once #include #include #include #include #include #include "list.h" #include "macro.h" #include "ratelimit.h" #include "stdio-util.h" /* Some structures we reference but don't want to pull in headers for */ struct iovec; struct signalfd_siginfo; typedef enum LogTarget{ LOG_TARGET_CONSOLE, LOG_TARGET_CONSOLE_PREFIXED, LOG_TARGET_KMSG, LOG_TARGET_JOURNAL, LOG_TARGET_JOURNAL_OR_KMSG, LOG_TARGET_SYSLOG, LOG_TARGET_SYSLOG_OR_KMSG, LOG_TARGET_AUTO, /* console if stderr is not journal, JOURNAL_OR_KMSG otherwise */ LOG_TARGET_NULL, _LOG_TARGET_MAX, _LOG_TARGET_INVALID = -EINVAL, } LogTarget; /* This log level disables logging completely. It can only be passed to log_set_max_level() and cannot be * used a regular log level. */ #define LOG_NULL (LOG_EMERG - 1) /* Note to readers: << and >> have lower precedence (are evaluated earlier) than & and | */ #define SYNTHETIC_ERRNO(num) (1 << 30 | (num)) #define IS_SYNTHETIC_ERRNO(val) ((val) >> 30 & 1) #define ERRNO_VALUE(val) (abs(val) & ~(1 << 30)) /* The callback function to be invoked when syntax warnings are seen * in the unit files. */ typedef void (*log_syntax_callback_t)(const char *unit, int level, void *userdata); void set_log_syntax_callback(log_syntax_callback_t cb, void *userdata); static inline void clear_log_syntax_callback(dummy_t *dummy) { set_log_syntax_callback(/* cb= */ NULL, /* userdata= */ NULL); } const char *log_target_to_string(LogTarget target) _const_; LogTarget log_target_from_string(const char *s) _pure_; void log_set_target(LogTarget target); void log_set_target_and_open(LogTarget target); int log_set_target_from_string(const char *e); LogTarget log_get_target(void) _pure_; void log_set_max_level(int level); int log_set_max_level_from_string(const char *e); int log_get_max_level(void) _pure_; void log_set_facility(int facility); void log_show_color(bool b); bool log_get_show_color(void) _pure_; void log_show_location(bool b); bool log_get_show_location(void) _pure_; void log_show_time(bool b); bool log_get_show_time(void) _pure_; void log_show_tid(bool b); bool log_get_show_tid(void) _pure_; int log_show_color_from_string(const char *e); int log_show_location_from_string(const char *e); int log_show_time_from_string(const char *e); int log_show_tid_from_string(const char *e); /* Functions below that open and close logs or configure logging based on the * environment should not be called from library code — this is always a job * for the application itself. */ assert_cc(STRLEN(__FILE__) > STRLEN(RELATIVE_SOURCE_PATH) + 1); #define PROJECT_FILE (&__FILE__[STRLEN(RELATIVE_SOURCE_PATH) + 1]) int log_open(void); void log_close(void); void log_forget_fds(void); void log_parse_environment_variables(void); void log_parse_environment(void); int log_dispatch_internal( int level, int error, const char *file, int line, const char *func, const char *object_field, const char *object, const char *extra, const char *extra_field, char *buffer); int log_internal( int level, int error, const char *file, int line, const char *func, const char *format, ...) _printf_(6,7); int log_internalv( int level, int error, const char *file, int line, const char *func, const char *format, va_list ap) _printf_(6,0); int log_object_internalv( int level, int error, const char *file, int line, const char *func, const char *object_field, const char *object, const char *extra_field, const char *extra, const char *format, va_list ap) _printf_(10,0); int log_object_internal( int level, int error, const char *file, int line, const char *func, const char *object_field, const char *object, const char *extra_field, const char *extra, const char *format, ...) _printf_(10,11); int log_struct_internal( int level, int error, const char *file, int line, const char *func, const char *format, ...) _printf_(6,0) _sentinel_; int log_oom_internal( int level, const char *file, int line, const char *func); int log_format_iovec( struct iovec *iovec, size_t iovec_len, size_t *n, bool newline_separator, int error, const char *format, va_list ap) _printf_(6, 0); int log_struct_iovec_internal( int level, int error, const char *file, int line, const char *func, const struct iovec *input_iovec, size_t n_input_iovec); /* This modifies the buffer passed! */ int log_dump_internal( int level, int error, const char *file, int line, const char *func, char *buffer); /* Logging for various assertions */ _noreturn_ void log_assert_failed( const char *text, const char *file, int line, const char *func); _noreturn_ void log_assert_failed_unreachable( const char *file, int line, const char *func); void log_assert_failed_return( const char *text, const char *file, int line, const char *func); #define log_dispatch(level, error, buffer) \ log_dispatch_internal(level, error, PROJECT_FILE, __LINE__, __func__, NULL, NULL, NULL, NULL, buffer) /* Logging with level */ #define log_full_errno_zerook(level, error, ...) \ ({ \ int _level = (level), _e = (error); \ _e = (log_get_max_level() >= LOG_PRI(_level)) \ ? log_internal(_level, _e, PROJECT_FILE, __LINE__, __func__, __VA_ARGS__) \ : -ERRNO_VALUE(_e); \ _e < 0 ? _e : -ESTRPIPE; \ }) #if BUILD_MODE_DEVELOPER && !defined(TEST_CODE) # define ASSERT_NON_ZERO(x) assert((x) != 0) #else # define ASSERT_NON_ZERO(x) #endif #define log_full_errno(level, error, ...) \ ({ \ int _error = (error); \ ASSERT_NON_ZERO(_error); \ log_full_errno_zerook(level, _error, __VA_ARGS__); \ }) #define log_full(level, fmt, ...) \ ({ \ if (BUILD_MODE_DEVELOPER) \ assert(!strstr(fmt, "%m")); \ (void) log_full_errno_zerook(level, 0, fmt, ##__VA_ARGS__); \ }) int log_emergency_level(void); /* Normal logging */ #define log_debug(...) log_full(LOG_DEBUG, __VA_ARGS__) #define log_info(...) log_full(LOG_INFO, __VA_ARGS__) #define log_notice(...) log_full(LOG_NOTICE, __VA_ARGS__) #define log_warning(...) log_full(LOG_WARNING, __VA_ARGS__) #define log_error(...) log_full(LOG_ERR, __VA_ARGS__) #define log_emergency(...) log_full(log_emergency_level(), __VA_ARGS__) /* Logging triggered by an errno-like error */ #define log_debug_errno(error, ...) log_full_errno(LOG_DEBUG, error, __VA_ARGS__) #define log_info_errno(error, ...) log_full_errno(LOG_INFO, error, __VA_ARGS__) #define log_notice_errno(error, ...) log_full_errno(LOG_NOTICE, error, __VA_ARGS__) #define log_warning_errno(error, ...) log_full_errno(LOG_WARNING, error, __VA_ARGS__) #define log_error_errno(error, ...) log_full_errno(LOG_ERR, error, __VA_ARGS__) #define log_emergency_errno(error, ...) log_full_errno(log_emergency_level(), error, __VA_ARGS__) /* This logs at the specified level the first time it is called, and then * logs at debug. If the specified level is debug, this logs only the first * time it is called. */ #define log_once(level, ...) \ ({ \ if (ONCE) \ log_full(level, __VA_ARGS__); \ else if (LOG_PRI(level) != LOG_DEBUG) \ log_debug(__VA_ARGS__); \ }) #define log_once_errno(level, error, ...) \ ({ \ int _err = (error); \ if (ONCE) \ _err = log_full_errno(level, _err, __VA_ARGS__); \ else if (LOG_PRI(level) != LOG_DEBUG) \ _err = log_debug_errno(_err, __VA_ARGS__); \ else \ _err = -ERRNO_VALUE(_err); \ _err; \ }) #if LOG_TRACE # define log_trace(...) log_debug(__VA_ARGS__) # define log_trace_errno(...) log_debug_errno(__VA_ARGS__) #else # define log_trace(...) do {} while (0) # define log_trace_errno(e, ...) (-ERRNO_VALUE(e)) #endif /* Structured logging */ #define log_struct_errno(level, error, ...) \ log_struct_internal(level, error, PROJECT_FILE, __LINE__, __func__, __VA_ARGS__, NULL) #define log_struct(level, ...) log_struct_errno(level, 0, __VA_ARGS__) #define log_struct_iovec_errno(level, error, iovec, n_iovec) \ log_struct_iovec_internal(level, error, PROJECT_FILE, __LINE__, __func__, iovec, n_iovec) #define log_struct_iovec(level, iovec, n_iovec) log_struct_iovec_errno(level, 0, iovec, n_iovec) /* This modifies the buffer passed! */ #define log_dump(level, buffer) \ log_dump_internal(level, 0, PROJECT_FILE, __LINE__, __func__, buffer) #define log_oom() log_oom_internal(LOG_ERR, PROJECT_FILE, __LINE__, __func__) #define log_oom_debug() log_oom_internal(LOG_DEBUG, PROJECT_FILE, __LINE__, __func__) #define log_oom_warning() log_oom_internal(LOG_WARNING, PROJECT_FILE, __LINE__, __func__) bool log_on_console(void) _pure_; /* Helper to wrap the main message in structured logging. The macro doesn't do much, * except to provide visual grouping of the format string and its arguments. */ #if LOG_MESSAGE_VERIFICATION || defined(__COVERITY__) /* Do a fake formatting of the message string to let the scanner verify the arguments against the format * message. The variable will never be set to true, but we don't tell the compiler that :) */ extern bool _log_message_dummy; # define LOG_MESSAGE(fmt, ...) "MESSAGE=%.0d" fmt, (_log_message_dummy && printf(fmt, ##__VA_ARGS__)), ##__VA_ARGS__ #else # define LOG_MESSAGE(fmt, ...) "MESSAGE=" fmt, ##__VA_ARGS__ #endif void log_received_signal(int level, const struct signalfd_siginfo *si); /* If turned on, any requests for a log target involving "syslog" will be implicitly upgraded to the equivalent journal target */ void log_set_upgrade_syslog_to_journal(bool b); /* If turned on, and log_open() is called, we'll not use STDERR_FILENO for logging ever, but rather open /dev/console */ void log_set_always_reopen_console(bool b); /* If turned on, we'll open the log stream implicitly if needed on each individual log call. This is normally not * desired as we want to reuse our logging streams. It is useful however */ void log_set_open_when_needed(bool b); /* 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 * stderr, the console or kmsg */ void log_set_prohibit_ipc(bool b); int log_dup_console(void); int log_syntax_internal( const char *unit, int level, const char *config_file, unsigned config_line, int error, const char *file, int line, const char *func, const char *format, ...) _printf_(9, 10); int log_syntax_invalid_utf8_internal( const char *unit, int level, const char *config_file, unsigned config_line, const char *file, int line, const char *func, const char *rvalue); #define log_syntax(unit, level, config_file, config_line, error, ...) \ ({ \ int _level = (level), _e = (error); \ (log_get_max_level() >= LOG_PRI(_level)) \ ? log_syntax_internal(unit, _level, config_file, config_line, _e, PROJECT_FILE, __LINE__, __func__, __VA_ARGS__) \ : -ERRNO_VALUE(_e); \ }) #define log_syntax_invalid_utf8(unit, level, config_file, config_line, rvalue) \ ({ \ int _level = (level); \ (log_get_max_level() >= LOG_PRI(_level)) \ ? log_syntax_invalid_utf8_internal(unit, _level, config_file, config_line, PROJECT_FILE, __LINE__, __func__, rvalue) \ : -EINVAL; \ }) #define DEBUG_LOGGING _unlikely_(log_get_max_level() >= LOG_DEBUG) void log_setup(void); typedef struct LogRateLimit { int error; int level; RateLimit ratelimit; } LogRateLimit; #define log_ratelimit_internal(_level, _error, _ratelimit, _format, _file, _line, _func, ...) \ ({ \ int _log_ratelimit_error = (_error); \ int _log_ratelimit_level = (_level); \ static LogRateLimit _log_ratelimit = { \ .ratelimit = (_ratelimit), \ }; \ unsigned _num_dropped_errors = ratelimit_num_dropped(&_log_ratelimit.ratelimit); \ if (_log_ratelimit_error != _log_ratelimit.error || _log_ratelimit_level != _log_ratelimit.level) { \ ratelimit_reset(&_log_ratelimit.ratelimit); \ _log_ratelimit.error = _log_ratelimit_error; \ _log_ratelimit.level = _log_ratelimit_level; \ } \ if (log_get_max_level() == LOG_DEBUG || ratelimit_below(&_log_ratelimit.ratelimit)) \ _log_ratelimit_error = _num_dropped_errors > 0 \ ? log_internal(_log_ratelimit_level, _log_ratelimit_error, _file, _line, _func, _format " (Dropped %u similar message(s))", ##__VA_ARGS__, _num_dropped_errors) \ : log_internal(_log_ratelimit_level, _log_ratelimit_error, _file, _line, _func, _format, ##__VA_ARGS__); \ _log_ratelimit_error; \ }) #define log_ratelimit_full_errno(level, error, _ratelimit, format, ...) \ ({ \ int _level = (level), _e = (error); \ _e = (log_get_max_level() >= LOG_PRI(_level)) \ ? log_ratelimit_internal(_level, _e, _ratelimit, format, PROJECT_FILE, __LINE__, __func__, ##__VA_ARGS__) \ : -ERRNO_VALUE(_e); \ _e < 0 ? _e : -ESTRPIPE; \ }) #define log_ratelimit_full(level, _ratelimit, format, ...) \ log_ratelimit_full_errno(level, 0, _ratelimit, format, ##__VA_ARGS__) /* Normal logging */ #define log_ratelimit_info(...) log_ratelimit_full(LOG_INFO, __VA_ARGS__) #define log_ratelimit_notice(...) log_ratelimit_full(LOG_NOTICE, __VA_ARGS__) #define log_ratelimit_warning(...) log_ratelimit_full(LOG_WARNING, __VA_ARGS__) #define log_ratelimit_error(...) log_ratelimit_full(LOG_ERR, __VA_ARGS__) #define log_ratelimit_emergency(...) log_ratelimit_full(log_emergency_level(), __VA_ARGS__) /* Logging triggered by an errno-like error */ #define log_ratelimit_info_errno(error, ...) log_ratelimit_full_errno(LOG_INFO, error, __VA_ARGS__) #define log_ratelimit_notice_errno(error, ...) log_ratelimit_full_errno(LOG_NOTICE, error, __VA_ARGS__) #define log_ratelimit_warning_errno(error, ...) log_ratelimit_full_errno(LOG_WARNING, error, __VA_ARGS__) #define log_ratelimit_error_errno(error, ...) log_ratelimit_full_errno(LOG_ERR, error, __VA_ARGS__) #define log_ratelimit_emergency_errno(error, ...) log_ratelimit_full_errno(log_emergency_level(), error, __VA_ARGS__) /* * The log context allows attaching extra metadata to log messages written to the journal via log.h. We keep * track of a thread local log context onto which we can push extra metadata fields that should be logged. * * LOG_CONTEXT_PUSH() will add the provided field to the log context and will remove it again when the * current block ends. LOG_CONTEXT_PUSH_STRV() will do the same but for all fields in the given strv. * LOG_CONTEXT_PUSHF() is like LOG_CONTEXT_PUSH() but takes a format string and arguments. * * Using the macros is as simple as putting them anywhere inside a block to add a field to all following log * messages logged from inside that block. * * void myfunction(...) { * ... * * LOG_CONTEXT_PUSHF("MYMETADATA=%s", "abc"); * * // Every journal message logged will now have the MYMETADATA=abc * // field included. * } * * One special case to note is async code, where we use callbacks that are invoked to continue processing * when some event occurs. For async code, there's usually an associated "userdata" struct containing all the * information associated with the async operation. In this "userdata" struct, we can store a log context * allocated with log_context_new() and freed with log_context_free(). We can then add and remove fields to * the `fields` member of the log context object and all those fields will be logged along with each log * message. */ typedef struct LogContext LogContext; bool log_context_enabled(void); LogContext* log_context_attach(LogContext *c); LogContext* log_context_detach(LogContext *c); LogContext* log_context_new(char **fields, bool owned); LogContext* log_context_free(LogContext *c); /* Same as log_context_new(), but frees the given fields strv on failure. */ LogContext* log_context_new_consume(char **fields); /* Returns the number of attached log context objects. */ size_t log_context_num_contexts(void); /* Returns the number of fields in all attached log contexts. */ size_t log_context_num_fields(void); DEFINE_TRIVIAL_CLEANUP_FUNC(LogContext*, log_context_detach); DEFINE_TRIVIAL_CLEANUP_FUNC(LogContext*, log_context_free); #define LOG_CONTEXT_PUSH(...) \ LOG_CONTEXT_PUSH_STRV(STRV_MAKE(__VA_ARGS__)) #define LOG_CONTEXT_PUSHF(...) \ LOG_CONTEXT_PUSH(snprintf_ok((char[LINE_MAX]) {}, LINE_MAX, __VA_ARGS__)) #define _LOG_CONTEXT_PUSH_STRV(strv, c) \ _unused_ _cleanup_(log_context_freep) LogContext *c = log_context_new(strv, /*owned=*/ false); #define LOG_CONTEXT_PUSH_STRV(strv) \ _LOG_CONTEXT_PUSH_STRV(strv, UNIQ_T(c, UNIQ)) /* LOG_CONTEXT_CONSUME_STR()/LOG_CONTEXT_CONSUME_STRV() are identical to * LOG_CONTEXT_PUSH_STR()/LOG_CONTEXT_PUSH_STRV() except they take ownership of the given str/strv argument. */ #define _LOG_CONTEXT_CONSUME_STR(s, c, strv) \ _unused_ _cleanup_strv_free_ strv = strv_new(s); \ if (!strv) \ free(s); \ _unused_ _cleanup_(log_context_freep) LogContext *c = log_context_new_consume(TAKE_PTR(strv)) #define LOG_CONTEXT_CONSUME_STR(s) \ _LOG_CONTEXT_CONSUME_STR(s, UNIQ_T(c, UNIQ), UNIQ_T(sv, UNIQ)) #define _LOG_CONTEXT_CONSUME_STRV(strv, c) \ _unused_ _cleanup_(log_context_freep) LogContext *c = log_context_new_consume(strv); #define LOG_CONTEXT_CONSUME_STRV(strv) \ _LOG_CONTEXT_CONSUME_STRV(strv, UNIQ_T(c, UNIQ))