view src/core/ngx_log.h @ 9299:2706b60dc225 default tip

Core: error logging rate limiting. With this change, error logging to files can be rate-limited with the "rate=" parameter. The parameter specifies allowed log messages rate to a particular file (per worker), in messages per second (m/s). By default, "rate=1000m/s" is used. Rate limiting is implemented using the "leaky bucket" method, similarly to the limit_req module. Maximum burst size is set to the number of log messages per second for each severity level, so "error" messages are logged even if the rate limit is hit by "info" messages (but not vice versa). When the limit is reached for a particular level, the "too many log messages, limiting" message is logged at this level. If debug logging is enabled, either for the particular log file or for the particular connection, rate limiting is not used.
author Maxim Dounin <mdounin@mdounin.ru>
date Tue, 25 Jun 2024 22:58:56 +0300
parents af5b47569cb2
children
line wrap: on
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/*
 * Copyright (C) Igor Sysoev
 * Copyright (C) Nginx, Inc.
 */


#ifndef _NGX_LOG_H_INCLUDED_
#define _NGX_LOG_H_INCLUDED_


#include <ngx_config.h>
#include <ngx_core.h>


#define NGX_LOG_STDERR            0
#define NGX_LOG_EMERG             1
#define NGX_LOG_ALERT             2
#define NGX_LOG_CRIT              3
#define NGX_LOG_ERR               4
#define NGX_LOG_WARN              5
#define NGX_LOG_NOTICE            6
#define NGX_LOG_INFO              7
#define NGX_LOG_DEBUG             8

#define NGX_LOG_DEBUG_CORE        0x010
#define NGX_LOG_DEBUG_ALLOC       0x020
#define NGX_LOG_DEBUG_MUTEX       0x040
#define NGX_LOG_DEBUG_EVENT       0x080
#define NGX_LOG_DEBUG_HTTP        0x100
#define NGX_LOG_DEBUG_MAIL        0x200
#define NGX_LOG_DEBUG_STREAM      0x400

/*
 * do not forget to update debug_levels[] in src/core/ngx_log.c
 * after the adding a new debug level
 */

#define NGX_LOG_DEBUG_FIRST       NGX_LOG_DEBUG_CORE
#define NGX_LOG_DEBUG_LAST        NGX_LOG_DEBUG_STREAM
#define NGX_LOG_DEBUG_CONNECTION  0x80000000
#define NGX_LOG_DEBUG_ALL         0x7ffffff0


typedef u_char *(*ngx_log_handler_pt) (ngx_log_t *log, u_char *buf, size_t len);
typedef void (*ngx_log_writer_pt) (ngx_log_t *log, ngx_uint_t level,
    u_char *buf, size_t len);


typedef struct {
    ngx_uint_t           rate;
    ngx_atomic_t         excess;
    ngx_atomic_t         last;
} ngx_log_limit_t;


struct ngx_log_s {
    ngx_uint_t           log_level;
    ngx_open_file_t     *file;

    ngx_atomic_uint_t    connection;

    ngx_log_handler_pt   handler;
    void                *data;

    ngx_log_writer_pt    writer;
    void                *wdata;

    /*
     * we declare "action" as "char *" because the actions are usually
     * the static strings and in the "u_char *" case we have to override
     * their types all the time
     */

    char                *action;

    ngx_log_limit_t     *limit;

    ngx_log_t           *next;
};


#define NGX_MAX_ERROR_STR   2048


/*********************************/

#if (NGX_HAVE_C99_VARIADIC_MACROS)

#define NGX_HAVE_VARIADIC_MACROS  1

#define ngx_log_error(level, log, ...)                                        \
    if ((log)->log_level >= level) ngx_log_error_core(level, log, __VA_ARGS__)

void ngx_log_error_core(ngx_uint_t level, ngx_log_t *log, ngx_err_t err,
    const char *fmt, ...);

#define ngx_log_debug(level, log, ...)                                        \
    if ((log)->log_level & level)                                             \
        ngx_log_error_core(NGX_LOG_DEBUG, log, __VA_ARGS__)

/*********************************/

#elif (NGX_HAVE_GCC_VARIADIC_MACROS)

#define NGX_HAVE_VARIADIC_MACROS  1

#define ngx_log_error(level, log, args...)                                    \
    if ((log)->log_level >= level) ngx_log_error_core(level, log, args)

void ngx_log_error_core(ngx_uint_t level, ngx_log_t *log, ngx_err_t err,
    const char *fmt, ...);

#define ngx_log_debug(level, log, args...)                                    \
    if ((log)->log_level & level)                                             \
        ngx_log_error_core(NGX_LOG_DEBUG, log, args)

/*********************************/

#else /* no variadic macros */

#define NGX_HAVE_VARIADIC_MACROS  0

void ngx_cdecl ngx_log_error(ngx_uint_t level, ngx_log_t *log, ngx_err_t err,
    const char *fmt, ...);
void ngx_log_error_core(ngx_uint_t level, ngx_log_t *log, ngx_err_t err,
    const char *fmt, va_list args);
void ngx_cdecl ngx_log_debug_core(ngx_log_t *log, ngx_err_t err,
    const char *fmt, ...);


#endif /* variadic macros */


/*********************************/

#if (NGX_DEBUG)

#if (NGX_HAVE_VARIADIC_MACROS)

#define ngx_log_debug0(level, log, err, fmt)                                  \
        ngx_log_debug(level, log, err, fmt)

#define ngx_log_debug1(level, log, err, fmt, arg1)                            \
        ngx_log_debug(level, log, err, fmt, arg1)

#define ngx_log_debug2(level, log, err, fmt, arg1, arg2)                      \
        ngx_log_debug(level, log, err, fmt, arg1, arg2)

#define ngx_log_debug3(level, log, err, fmt, arg1, arg2, arg3)                \
        ngx_log_debug(level, log, err, fmt, arg1, arg2, arg3)

#define ngx_log_debug4(level, log, err, fmt, arg1, arg2, arg3, arg4)          \
        ngx_log_debug(level, log, err, fmt, arg1, arg2, arg3, arg4)

#define ngx_log_debug5(level, log, err, fmt, arg1, arg2, arg3, arg4, arg5)    \
        ngx_log_debug(level, log, err, fmt, arg1, arg2, arg3, arg4, arg5)

#define ngx_log_debug6(level, log, err, fmt,                                  \
                       arg1, arg2, arg3, arg4, arg5, arg6)                    \
        ngx_log_debug(level, log, err, fmt,                                   \
                       arg1, arg2, arg3, arg4, arg5, arg6)

#define ngx_log_debug7(level, log, err, fmt,                                  \
                       arg1, arg2, arg3, arg4, arg5, arg6, arg7)              \
        ngx_log_debug(level, log, err, fmt,                                   \
                       arg1, arg2, arg3, arg4, arg5, arg6, arg7)

#define ngx_log_debug8(level, log, err, fmt,                                  \
                       arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8)        \
        ngx_log_debug(level, log, err, fmt,                                   \
                       arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8)


#else /* no variadic macros */

#define ngx_log_debug0(level, log, err, fmt)                                  \
    if ((log)->log_level & level)                                             \
        ngx_log_debug_core(log, err, fmt)

#define ngx_log_debug1(level, log, err, fmt, arg1)                            \
    if ((log)->log_level & level)                                             \
        ngx_log_debug_core(log, err, fmt, arg1)

#define ngx_log_debug2(level, log, err, fmt, arg1, arg2)                      \
    if ((log)->log_level & level)                                             \
        ngx_log_debug_core(log, err, fmt, arg1, arg2)

#define ngx_log_debug3(level, log, err, fmt, arg1, arg2, arg3)                \
    if ((log)->log_level & level)                                             \
        ngx_log_debug_core(log, err, fmt, arg1, arg2, arg3)

#define ngx_log_debug4(level, log, err, fmt, arg1, arg2, arg3, arg4)          \
    if ((log)->log_level & level)                                             \
        ngx_log_debug_core(log, err, fmt, arg1, arg2, arg3, arg4)

#define ngx_log_debug5(level, log, err, fmt, arg1, arg2, arg3, arg4, arg5)    \
    if ((log)->log_level & level)                                             \
        ngx_log_debug_core(log, err, fmt, arg1, arg2, arg3, arg4, arg5)

#define ngx_log_debug6(level, log, err, fmt,                                  \
                       arg1, arg2, arg3, arg4, arg5, arg6)                    \
    if ((log)->log_level & level)                                             \
        ngx_log_debug_core(log, err, fmt, arg1, arg2, arg3, arg4, arg5, arg6)

#define ngx_log_debug7(level, log, err, fmt,                                  \
                       arg1, arg2, arg3, arg4, arg5, arg6, arg7)              \
    if ((log)->log_level & level)                                             \
        ngx_log_debug_core(log, err, fmt,                                     \
                       arg1, arg2, arg3, arg4, arg5, arg6, arg7)

#define ngx_log_debug8(level, log, err, fmt,                                  \
                       arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8)        \
    if ((log)->log_level & level)                                             \
        ngx_log_debug_core(log, err, fmt,                                     \
                       arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8)

#endif

#else /* !NGX_DEBUG */

#define ngx_log_debug0(level, log, err, fmt)
#define ngx_log_debug1(level, log, err, fmt, arg1)
#define ngx_log_debug2(level, log, err, fmt, arg1, arg2)
#define ngx_log_debug3(level, log, err, fmt, arg1, arg2, arg3)
#define ngx_log_debug4(level, log, err, fmt, arg1, arg2, arg3, arg4)
#define ngx_log_debug5(level, log, err, fmt, arg1, arg2, arg3, arg4, arg5)
#define ngx_log_debug6(level, log, err, fmt, arg1, arg2, arg3, arg4, arg5, arg6)
#define ngx_log_debug7(level, log, err, fmt, arg1, arg2, arg3, arg4, arg5,    \
                       arg6, arg7)
#define ngx_log_debug8(level, log, err, fmt, arg1, arg2, arg3, arg4, arg5,    \
                       arg6, arg7, arg8)

#endif

/*********************************/

ngx_log_t *ngx_log_init(u_char *prefix, u_char *error_log);
void ngx_cdecl ngx_log_abort(ngx_err_t err, const char *fmt, ...);
void ngx_cdecl ngx_log_stderr(ngx_err_t err, const char *fmt, ...);
u_char *ngx_log_errno(u_char *buf, u_char *last, ngx_err_t err);
ngx_int_t ngx_log_open_default(ngx_cycle_t *cycle);
ngx_int_t ngx_log_redirect_stderr(ngx_cycle_t *cycle);
ngx_log_t *ngx_log_get_file_log(ngx_log_t *head);
char *ngx_log_set_log(ngx_conf_t *cf, ngx_log_t **head);


/*
 * ngx_write_stderr() cannot be implemented as macro, since
 * MSVC does not allow to use #ifdef inside macro parameters.
 *
 * ngx_write_fd() is used instead of ngx_write_console(), since
 * CharToOemBuff() inside ngx_write_console() cannot be used with
 * read only buffer as destination and CharToOemBuff() is not needed
 * for ngx_write_stderr() anyway.
 */
static ngx_inline void
ngx_write_stderr(char *text)
{
    (void) ngx_write_fd(ngx_stderr, text, ngx_strlen(text));
}


static ngx_inline void
ngx_write_stdout(char *text)
{
    (void) ngx_write_fd(ngx_stdout, text, ngx_strlen(text));
}


extern ngx_module_t  ngx_errlog_module;
extern ngx_uint_t    ngx_use_stderr;


#endif /* _NGX_LOG_H_INCLUDED_ */