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Diffstat (limited to 'src/basic/log.h')
| -rw-r--r-- | src/basic/log.h | 409 |
1 files changed, 409 insertions, 0 deletions
diff --git a/src/basic/log.h b/src/basic/log.h new file mode 100644 index 0000000..560686e --- /dev/null +++ b/src/basic/log.h @@ -0,0 +1,409 @@ +/* SPDX-License-Identifier: LGPL-2.1-or-later */ +#pragma once + +#include <stdarg.h> +#include <stdbool.h> +#include <stdlib.h> +#include <string.h> +#include <syslog.h> + +#include "macro.h" +#include "ratelimit.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); +int log_set_target_from_string(const char *e); +LogTarget log_get_target(void) _pure_; +void log_settle_target(void); + +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__) + +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, _format, _file, _line, _func, ...) \ +({ \ + int _log_ratelimit_error = (_error); \ + int _log_ratelimit_level = (_level); \ + static LogRateLimit _log_ratelimit = { \ + .ratelimit = { \ + .interval = 1 * USEC_PER_SEC, \ + .burst = 1, \ + }, \ + }; \ + 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 (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, format, ...) \ + ({ \ + int _level = (level), _e = (error); \ + _e = (log_get_max_level() >= LOG_PRI(_level)) \ + ? log_ratelimit_internal(_level, _e, format, PROJECT_FILE, __LINE__, __func__, __VA_ARGS__) \ + : -ERRNO_VALUE(_e); \ + _e < 0 ? _e : -ESTRPIPE; \ + }) |