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-rw-r--r--src/basic/log.h537
1 files changed, 537 insertions, 0 deletions
diff --git a/src/basic/log.h b/src/basic/log.h
new file mode 100644
index 0000000..9008d47
--- /dev/null
+++ b/src/basic/log.h
@@ -0,0 +1,537 @@
+/* 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 "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_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__)
+#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__)
+
+const char *_log_set_prefix(const char *prefix, bool force);
+static inline const char *_log_unset_prefixp(const char **p) {
+ assert(p);
+ _log_set_prefix(*p, true);
+ return NULL;
+}
+
+#define LOG_SET_PREFIX(prefix) \
+ _cleanup_(_log_unset_prefixp) _unused_ const char *CONCATENATE(_cleanup_log_unset_prefix_, UNIQ) = _log_set_prefix(prefix, false);
+
+/*
+ * 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_new(const char *key, const char *value);
+LogContext* log_context_new_strv(char **fields, bool owned);
+LogContext* log_context_new_iov(struct iovec *input_iovec, size_t n_input_iovec, bool owned);
+
+/* Same as log_context_new(), but frees the given fields strv/iovec on failure. */
+LogContext* log_context_new_strv_consume(char **fields);
+LogContext* log_context_new_iov_consume(struct iovec *input_iovec, size_t n_input_iovec);
+
+LogContext *log_context_ref(LogContext *c);
+LogContext *log_context_unref(LogContext *c);
+
+DEFINE_TRIVIAL_CLEANUP_FUNC(LogContext*, log_context_unref);
+
+/* 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 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_KEY_VALUE(key, value, c) \
+ _unused_ _cleanup_(log_context_unrefp) LogContext *c = log_context_new(key, value);
+
+#define LOG_CONTEXT_PUSH_KEY_VALUE(key, value) \
+ _LOG_CONTEXT_PUSH_KEY_VALUE(key, value, UNIQ_T(c, UNIQ))
+
+#define _LOG_CONTEXT_PUSH_STRV(strv, c) \
+ _unused_ _cleanup_(log_context_unrefp) LogContext *c = log_context_new_strv(strv, /*owned=*/ false);
+
+#define LOG_CONTEXT_PUSH_STRV(strv) \
+ _LOG_CONTEXT_PUSH_STRV(strv, UNIQ_T(c, UNIQ))
+
+#define _LOG_CONTEXT_PUSH_IOV(input_iovec, n_input_iovec, c) \
+ _unused_ _cleanup_(log_context_unrefp) LogContext *c = log_context_new_iov(input_iovec, n_input_iovec, /*owned=*/ false);
+
+#define LOG_CONTEXT_PUSH_IOV(input_iovec, n_input_iovec) \
+ _LOG_CONTEXT_PUSH_IOV(input_iovec, n_input_iovec, UNIQ_T(c, UNIQ))
+
+/* LOG_CONTEXT_CONSUME_STR()/LOG_CONTEXT_CONSUME_STRV()/LOG_CONTEXT_CONSUME_IOV() are identical to
+ * LOG_CONTEXT_PUSH_STR()/LOG_CONTEXT_PUSH_STRV()/LOG_CONTEXT_PUSH_IOV() 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_unrefp) LogContext *c = log_context_new_strv_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_unrefp) LogContext *c = log_context_new_strv_consume(strv);
+
+#define LOG_CONTEXT_CONSUME_STRV(strv) \
+ _LOG_CONTEXT_CONSUME_STRV(strv, UNIQ_T(c, UNIQ))
+
+#define _LOG_CONTEXT_CONSUME_IOV(input_iovec, n_input_iovec, c) \
+ _unused_ _cleanup_(log_context_unrefp) LogContext *c = log_context_new_iov_consume(input_iovec, n_input_iovec);
+
+#define LOG_CONTEXT_CONSUME_IOV(input_iovec, n_input_iovec) \
+ _LOG_CONTEXT_CONSUME_IOV(input_iovec, n_input_iovec, UNIQ_T(c, UNIQ))
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-27 21:29:10 +0000