view src/core/ngx_log.h @ 9270:3d455e37abf8

Core: PID file writing synchronization. Now, ngx_daemon() does not call exit() in the parent process immediately, but instead waits for the child process to signal it actually started (and wrote the PID file if configured to). This ensures that the PID file already exists when the parent process exits. To make sure that signal handlers won't cause unexpected logging in the parent process if the child process dies (for example, due to errors when writing the PID file), ngx_init_signals() is moved to the child process. This resolves "PID file ... not readable (yet?) after start" and "Failed to parse PID from file..." errors as observed with systemd. Note that the errors observed are considered to be a bug in systemd, which isn't able to work properly with traditional Unix daemons. Still, the workaround is implemented to make sure there will be no OS vendor patches trying to address this.
author Maxim Dounin <mdounin@mdounin.ru>
date Mon, 13 May 2024 06:13:22 +0300
parents f18db38a9826
children af5b47569cb2
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);


struct ngx_log_s {
    ngx_uint_t           log_level;
    ngx_open_file_t     *file;

    ngx_atomic_uint_t    connection;

    time_t               disk_full_time;

    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_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_ */