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src/os

unix/ngx_linux_config.h

#ifndef _GNU_SOURCE
#define _GNU_SOURCE             /* pread(), pwrite(), gethostname() */
#endif

#define _FILE_OFFSET_BITS  64

#include <sys/types.h>
#include <sys/time.h>
#include <unistd.h>
#include <stdarg.h>
#include <stddef.h>             /* offsetof() */
#include <stdio.h>
#include <stdlib.h>
#include <ctype.h>
#include <errno.h>
#include <string.h>
#include <signal.h>
#include <pwd.h>
#include <grp.h>
#include <dirent.h>
#include <glob.h>
#include <sys/vfs.h>            /* statfs() */

#include <sys/uio.h>
#include <sys/stat.h>
#include <fcntl.h>

#include <sys/wait.h>
#include <sys/mman.h>
#include <sys/resource.h>
#include <sched.h>

#include <sys/socket.h>
#include <netinet/in.h>
#include <netinet/tcp.h>        /* TCP_NODELAY, TCP_CORK */
#include <arpa/inet.h>
#include <netdb.h>
#include <sys/un.h>

#include <time.h>               /* tzset() */
#include <malloc.h>             /* memalign() */
#include <limits.h>             /* IOV_MAX */
#include <sys/ioctl.h>
#include <crypt.h>
#include <sys/utsname.h>        /* uname() */

#include <dlfcn.h>

#include <ngx_auto_config.h>

#if (NGX_HAVE_POSIX_SEM)
#include <semaphore.h>
#endif

#if (NGX_HAVE_SYS_PRCTL_H)
#include <sys/prctl.h>
#endif

#if (NGX_HAVE_SENDFILE64)
#include <sys/sendfile.h>
#else
extern ssize_t sendfile(int s, int fd, int32_t *offset, size_t size);
#define NGX_SENDFILE_LIMIT  0x80000000
#endif

#if (NGX_HAVE_POLL)
#include <poll.h>
#endif

#if (NGX_HAVE_EPOLL)
#include <sys/epoll.h>
#endif

#if (NGX_HAVE_SYS_EVENTFD_H)
#include <sys/eventfd.h>
#endif
#include <sys/syscall.h>
#if (NGX_HAVE_FILE_AIO)
#include <linux/aio_abi.h>
typedef struct iocb  ngx_aiocb_t;
#endif

#define NGX_LISTEN_BACKLOG        511

#ifndef NGX_HAVE_SO_SNDLOWAT
/* setsockopt(SO_SNDLOWAT) returns ENOPROTOOPT */
#define NGX_HAVE_SO_SNDLOWAT         0
#endif

#ifndef NGX_HAVE_INHERITED_NONBLOCK
#define NGX_HAVE_INHERITED_NONBLOCK  0
#endif

#define NGX_HAVE_OS_SPECIFIC_INIT    1
#define ngx_debug_init()

extern char **environ;

nginx-1.10.2/src/core

ngx_config.h

#include <ngx_auto_headers.h>

#if defined __DragonFly__ && !defined __FreeBSD__
#define __FreeBSD__        4
#define __FreeBSD_version  480101
#endif

#if (NGX_FREEBSD)
#include <ngx_freebsd_config.h>

#elif (NGX_LINUX)
#include <ngx_linux_config.h>

#elif (NGX_SOLARIS)
#include <ngx_solaris_config.h>

#elif (NGX_DARWIN)
#include <ngx_darwin_config.h>

#elif (NGX_WIN32)
#include <ngx_win32_config.h>

#else /* POSIX */
#include <ngx_posix_config.h>

#endif

#ifndef NGX_HAVE_SO_SNDLOWAT
#define NGX_HAVE_SO_SNDLOWAT     1
#endif

#if !(NGX_WIN32)

#define ngx_signal_helper(n)     SIG##n
#define ngx_signal_value(n)      ngx_signal_helper(n)

#define ngx_random               random

/* TODO: #ifndef */
#define NGX_SHUTDOWN_SIGNAL      QUIT
#define NGX_TERMINATE_SIGNAL     TERM
#define NGX_NOACCEPT_SIGNAL      WINCH
#define NGX_RECONFIGURE_SIGNAL   HUP

#if (NGX_LINUXTHREADS)
#define NGX_REOPEN_SIGNAL        INFO
#define NGX_CHANGEBIN_SIGNAL     XCPU
#else
#define NGX_REOPEN_SIGNAL        USR1
#define NGX_CHANGEBIN_SIGNAL     USR2
#endif

#define ngx_cdecl
#define ngx_libc_cdecl

#endif

typedef intptr_t        ngx_int_t;
typedef uintptr_t       ngx_uint_t;
typedef intptr_t        ngx_flag_t;


#define NGX_INT32_LEN   (sizeof("-2147483648") - 1)
#define NGX_INT64_LEN   (sizeof("-9223372036854775808") - 1)

#if (NGX_PTR_SIZE == 4)
#define NGX_INT_T_LEN   NGX_INT32_LEN
#define NGX_MAX_INT_T_VALUE  2147483647

#else
#define NGX_INT_T_LEN   NGX_INT64_LEN
#define NGX_MAX_INT_T_VALUE  9223372036854775807
#endif


#ifndef NGX_ALIGNMENT
#define NGX_ALIGNMENT   sizeof(unsigned long)    /* platform word */
#endif

#define ngx_align(d, a)     (((d) + (a - 1)) & ~(a - 1))
#define ngx_align_ptr(p, a)                                                   \
    (u_char *) (((uintptr_t) (p) + ((uintptr_t) a - 1)) & ~((uintptr_t) a - 1))


#define ngx_abort       abort


/* TODO: platform specific: array[NGX_INVALID_ARRAY_INDEX] must cause SIGSEGV */
#define NGX_INVALID_ARRAY_INDEX 0x80000000


/* TODO: auto_conf: ngx_inline   inline __inline __inline__ */
#ifndef ngx_inline
#define ngx_inline      inline
#endif

#ifndef INADDR_NONE  /* Solaris */
#define INADDR_NONE  ((unsigned int) -1)
#endif

#ifdef MAXHOSTNAMELEN
#define NGX_MAXHOSTNAMELEN  MAXHOSTNAMELEN
#else
#define NGX_MAXHOSTNAMELEN  256
#endif


#define NGX_MAX_UINT32_VALUE  (uint32_t) 0xffffffff
#define NGX_MAX_INT32_VALUE   (uint32_t) 0x7fffffff


#endif /* _NGX_CONFIG_H_INCLUDED_ */

ngx_spinlock.c

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

void
ngx_spinlock(ngx_atomic_t *lock, ngx_atomic_int_t value, ngx_uint_t spin)
{
#if (NGX_HAVE_ATOMIC_OPS)
    ngx_uint_t  i, n;

    for ( ;; ) {
        if (*lock == 0 && ngx_atomic_cmp_set(lock, 0, value)) {
            return;
        }
        if (ngx_ncpu > 1) {
            for (n = 1; n < spin; n <<= 1) {

                for (i = 0; i < n; i++) {
                    ngx_cpu_pause();
                }

                if (*lock == 0 && ngx_atomic_cmp_set(lock, 0, value)) {
                    return;
                }
            }
        }
        ngx_sched_yield();
    }
#else
#if (NGX_THREADS)
#error ngx_spinlock() or ngx_atomic_cmp_set() are not defined !
#endif
#endif
}

nginx.c

int ngx_cdecl
main(int argc, char *const *argv)
{
    ngx_buf_t        *b;
    ngx_log_t        *log;
    ngx_uint_t        i;
    ngx_cycle_t      *cycle, init_cycle;
    ngx_conf_dump_t  *cd;
    ngx_core_conf_t  *ccf;

    ngx_debug_init();

    if (ngx_strerror_init() != NGX_OK) {
        return 1;
    }

    if (ngx_get_options(argc, argv) != NGX_OK) {
        return 1;
    }

    if (ngx_show_version) {
        ngx_show_version_info();

        if (!ngx_test_config) {
            return 0;
        }
    }

    /* TODO */ ngx_max_sockets = -1;

    ngx_time_init();

#if (NGX_PCRE)
    ngx_regex_init();
#endif

    ngx_pid = ngx_getpid();

    log = ngx_log_init(ngx_prefix);
    if (log == NULL) {
        return 1;
    }

    /* STUB */
#if (NGX_OPENSSL)
    ngx_ssl_init(log);
#endif

    /*
     * init_cycle->log is required for signal handlers and
     * ngx_process_options()
     */

    ngx_memzero(&init_cycle, sizeof(ngx_cycle_t));
    init_cycle.log = log;
    ngx_cycle = &init_cycle;

    init_cycle.pool = ngx_create_pool(1024, log);
    if (init_cycle.pool == NULL) {
        return 1;
    }

    if (ngx_save_argv(&init_cycle, argc, argv) != NGX_OK) {
        return 1;
    }

    if (ngx_process_options(&init_cycle) != NGX_OK) {
        return 1;
    }

    if (ngx_os_init(log) != NGX_OK) {
        return 1;
    }

    /*
     * ngx_crc32_table_init() requires ngx_cacheline_size set in ngx_os_init()
     */

    if (ngx_crc32_table_init() != NGX_OK) {
        return 1;
    }

    if (ngx_add_inherited_sockets(&init_cycle) != NGX_OK) {
        return 1;
    }

    if (ngx_preinit_modules() != NGX_OK) {
        return 1;
    }

    cycle = ngx_init_cycle(&init_cycle);
    if (cycle == NULL) {
        if (ngx_test_config) {
            ngx_log_stderr(0, "configuration file %s test failed",
                           init_cycle.conf_file.data);
        }

        return 1;
    }

    if (ngx_test_config) {
        if (!ngx_quiet_mode) {
            ngx_log_stderr(0, "configuration file %s test is successful",
                           cycle->conf_file.data);
        }

        if (ngx_dump_config) {
            cd = cycle->config_dump.elts;

            for (i = 0; i < cycle->config_dump.nelts; i++) {

                ngx_write_stdout("# configuration file ");
                (void) ngx_write_fd(ngx_stdout, cd[i].name.data,
                                    cd[i].name.len);
                ngx_write_stdout(":" NGX_LINEFEED);

                b = cd[i].buffer;

                (void) ngx_write_fd(ngx_stdout, b->pos, b->last - b->pos);
                ngx_write_stdout(NGX_LINEFEED);
            }
        }

        return 0;
    }

    if (ngx_signal) {
        return ngx_signal_process(cycle, ngx_signal);
    }

    ngx_os_status(cycle->log);

    ngx_cycle = cycle;

    ccf = (ngx_core_conf_t *) ngx_get_conf(cycle->conf_ctx, ngx_core_module);

    if (ccf->master && ngx_process == NGX_PROCESS_SINGLE) {
        ngx_process = NGX_PROCESS_MASTER;
    }

#if !(NGX_WIN32)

    if (ngx_init_signals(cycle->log) != NGX_OK) {
        return 1;
    }

    if (!ngx_inherited && ccf->daemon) {
        if (ngx_daemon(cycle->log) != NGX_OK) {
            return 1;
        }

        ngx_daemonized = 1;
    }

    if (ngx_inherited) {
        ngx_daemonized = 1;
    }

#endif

    if (ngx_create_pidfile(&ccf->pid, cycle->log) != NGX_OK) {
        return 1;
    }

    if (ngx_log_redirect_stderr(cycle) != NGX_OK) {
        return 1;
    }

    if (log->file->fd != ngx_stderr) {
        if (ngx_close_file(log->file->fd) == NGX_FILE_ERROR) {
            ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
                          ngx_close_file_n " built-in log failed");
        }
    }

    ngx_use_stderr = 0;

    if (ngx_process == NGX_PROCESS_SINGLE) {
        ngx_single_process_cycle(cycle);

    } else {
        ngx_master_process_cycle(cycle);
    }

    return 0;
}

ngx_times.{h,c}

typedef struct {
    time_t      sec;
    ngx_uint_t  msec;
    ngx_int_t   gmtoff;
} ngx_time_t;

void ngx_time_init(void);
void ngx_time_update(void);
void ngx_time_sigsafe_update(void);
u_char *ngx_http_time(u_char *buf, time_t t);
u_char *ngx_http_cookie_time(u_char *buf, time_t t);
void ngx_gmtime(time_t t, ngx_tm_t *tp);

time_t ngx_next_time(time_t when);
#define ngx_next_time_n      "mktime()"

extern volatile ngx_time_t  *ngx_cached_time;

#define ngx_time()           ngx_cached_time->sec
#define ngx_timeofday()      (ngx_time_t *) ngx_cached_time

extern volatile ngx_str_t    ngx_cached_err_log_time;
extern volatile ngx_str_t    ngx_cached_http_time;
extern volatile ngx_str_t    ngx_cached_http_log_time;
extern volatile ngx_str_t    ngx_cached_http_log_iso8601;
extern volatile ngx_str_t    ngx_cached_syslog_time;

/*
 * milliseconds elapsed since epoch and truncated to ngx_msec_t,
 * used in event timers
 */
extern volatile ngx_msec_t  ngx_current_msec;
/*
 * The time may be updated by signal handler or by several threads.
 * The time update operations are rare and require to hold the ngx_time_lock.
 * The time read operations are frequent, so they are lock-free and get time
 * values and strings from the current slot.  Thus thread may get the corrupted
 * values only if it is preempted while copying and then it is not scheduled
 * to run more than NGX_TIME_SLOTS seconds.
 */

#define NGX_TIME_SLOTS   64

static ngx_uint_t        slot;
static ngx_atomic_t      ngx_time_lock;

volatile ngx_msec_t      ngx_current_msec;
volatile ngx_time_t     *ngx_cached_time;
volatile ngx_str_t       ngx_cached_err_log_time;
volatile ngx_str_t       ngx_cached_http_time;
volatile ngx_str_t       ngx_cached_http_log_time;
volatile ngx_str_t       ngx_cached_http_log_iso8601;
volatile ngx_str_t       ngx_cached_syslog_time;

#if !(NGX_WIN32)

/*
 * localtime() and localtime_r() are not Async-Signal-Safe functions, therefore,
 * they must not be called by a signal handler, so we use the cached
 * GMT offset value. Fortunately the value is changed only two times a year.
 */

static ngx_int_t         cached_gmtoff;
#endif

static ngx_time_t        cached_time[NGX_TIME_SLOTS];
static u_char            cached_err_log_time[NGX_TIME_SLOTS]
                                    [sizeof("1970/09/28 12:00:00")];
static u_char            cached_http_time[NGX_TIME_SLOTS]
                                    [sizeof("Mon, 28 Sep 1970 06:00:00 GMT")];
static u_char            cached_http_log_time[NGX_TIME_SLOTS]
                                    [sizeof("28/Sep/1970:12:00:00 +0600")];
static u_char            cached_http_log_iso8601[NGX_TIME_SLOTS]
                                    [sizeof("1970-09-28T12:00:00+06:00")];
static u_char            cached_syslog_time[NGX_TIME_SLOTS]
                                    [sizeof("Sep 28 12:00:00")];


static char  *week[] = { "Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat" };
static char  *months[] = { "Jan", "Feb", "Mar", "Apr", "May", "Jun",
                           "Jul", "Aug", "Sep", "Oct", "Nov", "Dec" };

void
ngx_time_init(void)
{
    ngx_cached_err_log_time.len = sizeof("1970/09/28 12:00:00") - 1;
    ngx_cached_http_time.len = sizeof("Mon, 28 Sep 1970 06:00:00 GMT") - 1;
    ngx_cached_http_log_time.len = sizeof("28/Sep/1970:12:00:00 +0600") - 1;
    ngx_cached_http_log_iso8601.len = sizeof("1970-09-28T12:00:00+06:00") - 1;
    ngx_cached_syslog_time.len = sizeof("Sep 28 12:00:00") - 1;

    ngx_cached_time = &cached_time[0];

    ngx_time_update();
}

void
ngx_time_update(void)
{
    u_char          *p0, *p1, *p2, *p3, *p4;
    ngx_tm_t         tm, gmt;
    time_t           sec;
    ngx_uint_t       msec;
    ngx_time_t      *tp;
    struct timeval   tv;

    if (!ngx_trylock(&ngx_time_lock)) {
        return;
    }

    ngx_gettimeofday(&tv);

    sec = tv.tv_sec;
    msec = tv.tv_usec / 1000;

    ngx_current_msec = (ngx_msec_t) sec * 1000 + msec;

    tp = &cached_time[slot];

    if (tp->sec == sec) {
        tp->msec = msec;
        ngx_unlock(&ngx_time_lock);
        return;
    }

    if (slot == NGX_TIME_SLOTS - 1) {
        slot = 0;
    } else {
        slot++;
    }

    tp = &cached_time[slot];

    tp->sec = sec;
    tp->msec = msec;

    ngx_gmtime(sec, &gmt);


    p0 = &cached_http_time[slot][0];

    (void) ngx_sprintf(p0, "%s, %02d %s %4d %02d:%02d:%02d GMT",
                       week[gmt.ngx_tm_wday], gmt.ngx_tm_mday,
                       months[gmt.ngx_tm_mon - 1], gmt.ngx_tm_year,
                       gmt.ngx_tm_hour, gmt.ngx_tm_min, gmt.ngx_tm_sec);

#if (NGX_HAVE_GETTIMEZONE)

    tp->gmtoff = ngx_gettimezone();
    ngx_gmtime(sec + tp->gmtoff * 60, &tm);

#elif (NGX_HAVE_GMTOFF)

    ngx_localtime(sec, &tm);
    cached_gmtoff = (ngx_int_t) (tm.ngx_tm_gmtoff / 60);
    tp->gmtoff = cached_gmtoff;

#else

    ngx_localtime(sec, &tm);
    cached_gmtoff = ngx_timezone(tm.ngx_tm_isdst);
    tp->gmtoff = cached_gmtoff;

#endif


    p1 = &cached_err_log_time[slot][0];

    (void) ngx_sprintf(p1, "%4d/%02d/%02d %02d:%02d:%02d",
                       tm.ngx_tm_year, tm.ngx_tm_mon,
                       tm.ngx_tm_mday, tm.ngx_tm_hour,
                       tm.ngx_tm_min, tm.ngx_tm_sec);


    p2 = &cached_http_log_time[slot][0];

    (void) ngx_sprintf(p2, "%02d/%s/%d:%02d:%02d:%02d %c%02i%02i",
                       tm.ngx_tm_mday, months[tm.ngx_tm_mon - 1],
                       tm.ngx_tm_year, tm.ngx_tm_hour,
                       tm.ngx_tm_min, tm.ngx_tm_sec,
                       tp->gmtoff < 0 ? '-' : '+',
                       ngx_abs(tp->gmtoff / 60), ngx_abs(tp->gmtoff % 60));

    p3 = &cached_http_log_iso8601[slot][0];

    (void) ngx_sprintf(p3, "%4d-%02d-%02dT%02d:%02d:%02d%c%02i:%02i",
                       tm.ngx_tm_year, tm.ngx_tm_mon,
                       tm.ngx_tm_mday, tm.ngx_tm_hour,
                       tm.ngx_tm_min, tm.ngx_tm_sec,
                       tp->gmtoff < 0 ? '-' : '+',
                       ngx_abs(tp->gmtoff / 60), ngx_abs(tp->gmtoff % 60));

    p4 = &cached_syslog_time[slot][0];

    (void) ngx_sprintf(p4, "%s %2d %02d:%02d:%02d",
                       months[tm.ngx_tm_mon - 1], tm.ngx_tm_mday,
                       tm.ngx_tm_hour, tm.ngx_tm_min, tm.ngx_tm_sec);

    ngx_memory_barrier();

    ngx_cached_time = tp;
    ngx_cached_http_time.data = p0;
    ngx_cached_err_log_time.data = p1;
    ngx_cached_http_log_time.data = p2;
    ngx_cached_http_log_iso8601.data = p3;
    ngx_cached_syslog_time.data = p4;

    ngx_unlock(&ngx_time_lock);
}

#if !(NGX_WIN32)

void
ngx_time_sigsafe_update(void)
{
    u_char          *p, *p2;
    ngx_tm_t         tm;
    time_t           sec;
    ngx_time_t      *tp;
    struct timeval   tv;

    if (!ngx_trylock(&ngx_time_lock)) {
        return;
    }

    ngx_gettimeofday(&tv);

    sec = tv.tv_sec;

    tp = &cached_time[slot];

    if (tp->sec == sec) {
        ngx_unlock(&ngx_time_lock);
        return;
    }

    if (slot == NGX_TIME_SLOTS - 1) {
        slot = 0;
    } else {
        slot++;
    }

    tp = &cached_time[slot];

    tp->sec = 0;

    ngx_gmtime(sec + cached_gmtoff * 60, &tm);

    p = &cached_err_log_time[slot][0];

    (void) ngx_sprintf(p, "%4d/%02d/%02d %02d:%02d:%02d",
                       tm.ngx_tm_year, tm.ngx_tm_mon,
                       tm.ngx_tm_mday, tm.ngx_tm_hour,
                       tm.ngx_tm_min, tm.ngx_tm_sec);

    p2 = &cached_syslog_time[slot][0];

    (void) ngx_sprintf(p2, "%s %2d %02d:%02d:%02d",
                       months[tm.ngx_tm_mon - 1], tm.ngx_tm_mday,
                       tm.ngx_tm_hour, tm.ngx_tm_min, tm.ngx_tm_sec);

    ngx_memory_barrier();

    ngx_cached_err_log_time.data = p;
    ngx_cached_syslog_time.data = p2;

    ngx_unlock(&ngx_time_lock);
}

#endif

u_char *
ngx_http_time(u_char *buf, time_t t)
{
    ngx_tm_t  tm;

    ngx_gmtime(t, &tm);

    return ngx_sprintf(buf, "%s, %02d %s %4d %02d:%02d:%02d GMT",
                       week[tm.ngx_tm_wday],
                       tm.ngx_tm_mday,
                       months[tm.ngx_tm_mon - 1],
                       tm.ngx_tm_year,
                       tm.ngx_tm_hour,
                       tm.ngx_tm_min,
                       tm.ngx_tm_sec);
}

u_char *
ngx_http_cookie_time(u_char *buf, time_t t)
{
    ngx_tm_t  tm;

    ngx_gmtime(t, &tm);

    /*
     * Netscape 3.x does not understand 4-digit years at all and
     * 2-digit years more than "37"
     */

    return ngx_sprintf(buf,
                       (tm.ngx_tm_year > 2037) ?
                                         "%s, %02d-%s-%d %02d:%02d:%02d GMT":
                                         "%s, %02d-%s-%02d %02d:%02d:%02d GMT",
                       week[tm.ngx_tm_wday],
                       tm.ngx_tm_mday,
                       months[tm.ngx_tm_mon - 1],
                       (tm.ngx_tm_year > 2037) ? tm.ngx_tm_year:
                                                 tm.ngx_tm_year % 100,
                       tm.ngx_tm_hour,
                       tm.ngx_tm_min,
                       tm.ngx_tm_sec);
}

void
ngx_gmtime(time_t t, ngx_tm_t *tp)
{
    ngx_int_t   yday;
    ngx_uint_t  n, sec, min, hour, mday, mon, year, wday, days, leap;

    /* the calculation is valid for positive time_t only */

    n = (ngx_uint_t) t;

    days = n / 86400;

    /* January 1, 1970 was Thursday */

    wday = (4 + days) % 7;

    n %= 86400;
    hour = n / 3600;
    n %= 3600;
    min = n / 60;
    sec = n % 60;

    /*
     * the algorithm based on Gauss' formula,
     * see src/http/ngx_http_parse_time.c
     */

    /* days since March 1, 1 BC */
    days = days - (31 + 28) + 719527;

    /*
     * The "days" should be adjusted to 1 only, however, some March 1st's go
     * to previous year, so we adjust them to 2.  This causes also shift of the
     * last February days to next year, but we catch the case when "yday"
     * becomes negative.
     */

    year = (days + 2) * 400 / (365 * 400 + 100 - 4 + 1);

    yday = days - (365 * year + year / 4 - year / 100 + year / 400);

    if (yday < 0) {
        leap = (year % 4 == 0) && (year % 100 || (year % 400 == 0));
        yday = 365 + leap + yday;
        year--;
    }

    /*
     * The empirical formula that maps "yday" to month.
     * There are at least 10 variants, some of them are:
     *     mon = (yday + 31) * 15 / 459
     *     mon = (yday + 31) * 17 / 520
     *     mon = (yday + 31) * 20 / 612
     */

    mon = (yday + 31) * 10 / 306;

    /* the Gauss' formula that evaluates days before the month */

    mday = yday - (367 * mon / 12 - 30) + 1;

    if (yday >= 306) {

        year++;
        mon -= 10;

        /*
         * there is no "yday" in Win32 SYSTEMTIME
         *
         * yday -= 306;
         */

    } else {

        mon += 2;

        /*
         * there is no "yday" in Win32 SYSTEMTIME
         *
         * yday += 31 + 28 + leap;
         */
    }

    tp->ngx_tm_sec = (ngx_tm_sec_t) sec;
    tp->ngx_tm_min = (ngx_tm_min_t) min;
    tp->ngx_tm_hour = (ngx_tm_hour_t) hour;
    tp->ngx_tm_mday = (ngx_tm_mday_t) mday;
    tp->ngx_tm_mon = (ngx_tm_mon_t) mon;
    tp->ngx_tm_year = (ngx_tm_year_t) year;
    tp->ngx_tm_wday = (ngx_tm_wday_t) wday;
}

time_t
ngx_next_time(time_t when)
{
    time_t     now, next;
    struct tm  tm;

    now = ngx_time();

    ngx_libc_localtime(now, &tm);

    tm.tm_hour = (int) (when / 3600);
    when %= 3600;
    tm.tm_min = (int) (when / 60);
    tm.tm_sec = (int) (when % 60);

    next = mktime(&tm);

    if (next == -1) {
        return -1;
    }

    if (next - now > 0) {
        return next;
    }

    tm.tm_mday++;

    /* mktime() should normalize a date (Jan 32, etc) */

    next = mktime(&tm);

    if (next != -1) {
        return next;
    }

    return -1;
}

ngx_thread_pool.{h,c}

struct ngx_thread_task_s {
    ngx_thread_task_t   *next;
    ngx_uint_t           id;
    void                *ctx;
    void               (*handler)(void *data, ngx_log_t *log);
    ngx_event_t          event;
};

typedef struct ngx_thread_pool_s  ngx_thread_pool_t;

ngx_thread_pool_t *ngx_thread_pool_add(ngx_conf_t *cf, ngx_str_t *name);
ngx_thread_pool_t *ngx_thread_pool_get(ngx_cycle_t *cycle, ngx_str_t *name);

ngx_thread_task_t *ngx_thread_task_alloc(ngx_pool_t *pool, size_t size);
ngx_int_t ngx_thread_task_post(ngx_thread_pool_t *tp, ngx_thread_task_t *task);
typedef struct {
    ngx_array_t               pools;
} ngx_thread_pool_conf_t;

typedef struct {
    ngx_thread_task_t        *first;
    ngx_thread_task_t       **last;
} ngx_thread_pool_queue_t;

#define ngx_thread_pool_queue_init(q)                                         \
    (q)->first = NULL;                                                        \
    (q)->last = &(q)->first

struct ngx_thread_pool_s {
    ngx_thread_mutex_t        mtx;
    ngx_thread_pool_queue_t   queue;
    ngx_int_t                 waiting;
    ngx_thread_cond_t         cond;

    ngx_log_t                *log;

    ngx_str_t                 name;
    ngx_uint_t                threads;
    ngx_int_t                 max_queue;

    u_char                   *file;
    ngx_uint_t                line;
};

static ngx_int_t ngx_thread_pool_init(ngx_thread_pool_t *tp, ngx_log_t *log,
    ngx_pool_t *pool);
static void ngx_thread_pool_destroy(ngx_thread_pool_t *tp);
static void ngx_thread_pool_exit_handler(void *data, ngx_log_t *log);

static void *ngx_thread_pool_cycle(void *data);
static void ngx_thread_pool_handler(ngx_event_t *ev);

static char *ngx_thread_pool(ngx_conf_t *cf, ngx_command_t *cmd, void *conf);

static void *ngx_thread_pool_create_conf(ngx_cycle_t *cycle);
static char *ngx_thread_pool_init_conf(ngx_cycle_t *cycle, void *conf);

static ngx_int_t ngx_thread_pool_init_worker(ngx_cycle_t *cycle);
static void ngx_thread_pool_exit_worker(ngx_cycle_t *cycle);


static ngx_command_t  ngx_thread_pool_commands[] = {

    { ngx_string("thread_pool"),
      NGX_MAIN_CONF|NGX_DIRECT_CONF|NGX_CONF_TAKE23,
      ngx_thread_pool,
      0,
      0,
      NULL },

      ngx_null_command
};


static ngx_core_module_t  ngx_thread_pool_module_ctx = {
    ngx_string("thread_pool"),
    ngx_thread_pool_create_conf,
    ngx_thread_pool_init_conf
};


ngx_module_t  ngx_thread_pool_module = {
    NGX_MODULE_V1,
    &ngx_thread_pool_module_ctx,           /* module context */
    ngx_thread_pool_commands,              /* module directives */
    NGX_CORE_MODULE,                       /* module type */
    NULL,                                  /* init master */
    NULL,                                  /* init module */
    ngx_thread_pool_init_worker,           /* init process */
    NULL,                                  /* init thread */
    NULL,                                  /* exit thread */
    ngx_thread_pool_exit_worker,           /* exit process */
    NULL,                                  /* exit master */
    NGX_MODULE_V1_PADDING
};


static ngx_str_t  ngx_thread_pool_default = ngx_string("default");

static ngx_uint_t               ngx_thread_pool_task_id;
static ngx_atomic_t             ngx_thread_pool_done_lock;
static ngx_thread_pool_queue_t  ngx_thread_pool_done;


static ngx_int_t
ngx_thread_pool_init(ngx_thread_pool_t *tp, ngx_log_t *log, ngx_pool_t *pool)
{
    int             err;
    pthread_t       tid;
    ngx_uint_t      n;
    pthread_attr_t  attr;

    if (ngx_notify == NULL) {
        ngx_log_error(NGX_LOG_ALERT, log, 0,
               "the configured event method cannot be used with thread pools");
        return NGX_ERROR;
    }

    ngx_thread_pool_queue_init(&tp->queue);

    if (ngx_thread_mutex_create(&tp->mtx, log) != NGX_OK) {
        return NGX_ERROR;
    }

    if (ngx_thread_cond_create(&tp->cond, log) != NGX_OK) {
        (void) ngx_thread_mutex_destroy(&tp->mtx, log);
        return NGX_ERROR;
    }

    tp->log = log;

    err = pthread_attr_init(&attr);
    if (err) {
        ngx_log_error(NGX_LOG_ALERT, log, err,
                      "pthread_attr_init() failed");
        return NGX_ERROR;
    }

#if 0
    err = pthread_attr_setstacksize(&attr, PTHREAD_STACK_MIN);
    if (err) {
        ngx_log_error(NGX_LOG_ALERT, log, err,
                      "pthread_attr_setstacksize() failed");
        return NGX_ERROR;
    }
#endif

    for (n = 0; n < tp->threads; n++) {
        err = pthread_create(&tid, &attr, ngx_thread_pool_cycle, tp);
        if (err) {
            ngx_log_error(NGX_LOG_ALERT, log, err,
                          "pthread_create() failed");
            return NGX_ERROR;
        }
    }

    (void) pthread_attr_destroy(&attr);

    return NGX_OK;
}


static void
ngx_thread_pool_destroy(ngx_thread_pool_t *tp)
{
    ngx_uint_t           n;
    ngx_thread_task_t    task;
    volatile ngx_uint_t  lock;

    ngx_memzero(&task, sizeof(ngx_thread_task_t));

    task.handler = ngx_thread_pool_exit_handler;
    task.ctx = (void *) &lock;

    for (n = 0; n < tp->threads; n++) {
        lock = 1;

        if (ngx_thread_task_post(tp, &task) != NGX_OK) {
            return;
        }

        while (lock) {
            ngx_sched_yield();
        }

        task.event.active = 0;
    }

    (void) ngx_thread_cond_destroy(&tp->cond, tp->log);

    (void) ngx_thread_mutex_destroy(&tp->mtx, tp->log);
}


static void
ngx_thread_pool_exit_handler(void *data, ngx_log_t *log)
{
    ngx_uint_t *lock = data;

    *lock = 0;

    pthread_exit(0);
}


ngx_thread_task_t *
ngx_thread_task_alloc(ngx_pool_t *pool, size_t size)
{
    ngx_thread_task_t  *task;

    task = ngx_pcalloc(pool, sizeof(ngx_thread_task_t) + size);
    if (task == NULL) {
        return NULL;
    }

    task->ctx = task + 1;

    return task;
}


ngx_int_t
ngx_thread_task_post(ngx_thread_pool_t *tp, ngx_thread_task_t *task)
{
    if (task->event.active) {
        ngx_log_error(NGX_LOG_ALERT, tp->log, 0,
                      "task #%ui already active", task->id);
        return NGX_ERROR;
    }

    if (ngx_thread_mutex_lock(&tp->mtx, tp->log) != NGX_OK) {
        return NGX_ERROR;
    }

    if (tp->waiting >= tp->max_queue) {
        (void) ngx_thread_mutex_unlock(&tp->mtx, tp->log);

        ngx_log_error(NGX_LOG_ERR, tp->log, 0,
                      "thread pool \"%V\" queue overflow: %i tasks waiting",
                      &tp->name, tp->waiting);
        return NGX_ERROR;
    }

    task->event.active = 1;

    task->id = ngx_thread_pool_task_id++;
    task->next = NULL;

    if (ngx_thread_cond_signal(&tp->cond, tp->log) != NGX_OK) {
        (void) ngx_thread_mutex_unlock(&tp->mtx, tp->log);
        return NGX_ERROR;
    }

    *tp->queue.last = task;
    tp->queue.last = &task->next;

    tp->waiting++;

    (void) ngx_thread_mutex_unlock(&tp->mtx, tp->log);

    ngx_log_debug2(NGX_LOG_DEBUG_CORE, tp->log, 0,
                   "task #%ui added to thread pool \"%V\"",
                   task->id, &tp->name);

    return NGX_OK;
}


static void *
ngx_thread_pool_cycle(void *data)
{
    ngx_thread_pool_t *tp = data;

    int                 err;
    sigset_t            set;
    ngx_thread_task_t  *task;

#if 0
    ngx_time_update();
#endif

    ngx_log_debug1(NGX_LOG_DEBUG_CORE, tp->log, 0,
                   "thread in pool \"%V\" started", &tp->name);

    sigfillset(&set);

    sigdelset(&set, SIGILL);
    sigdelset(&set, SIGFPE);
    sigdelset(&set, SIGSEGV);
    sigdelset(&set, SIGBUS);

    err = pthread_sigmask(SIG_BLOCK, &set, NULL);
    if (err) {
        ngx_log_error(NGX_LOG_ALERT, tp->log, err, "pthread_sigmask() failed");
        return NULL;
    }

    for ( ;; ) {
        if (ngx_thread_mutex_lock(&tp->mtx, tp->log) != NGX_OK) {
            return NULL;
        }

        /* the number may become negative */
        tp->waiting--;

        while (tp->queue.first == NULL) {
            if (ngx_thread_cond_wait(&tp->cond, &tp->mtx, tp->log)
                != NGX_OK)
            {
                (void) ngx_thread_mutex_unlock(&tp->mtx, tp->log);
                return NULL;
            }
        }

        task = tp->queue.first;
        tp->queue.first = task->next;

        if (tp->queue.first == NULL) {
            tp->queue.last = &tp->queue.first;
        }

        if (ngx_thread_mutex_unlock(&tp->mtx, tp->log) != NGX_OK) {
            return NULL;
        }

#if 0
        ngx_time_update();
#endif

        ngx_log_debug2(NGX_LOG_DEBUG_CORE, tp->log, 0,
                       "run task #%ui in thread pool \"%V\"",
                       task->id, &tp->name);

        task->handler(task->ctx, tp->log);

        ngx_log_debug2(NGX_LOG_DEBUG_CORE, tp->log, 0,
                       "complete task #%ui in thread pool \"%V\"",
                       task->id, &tp->name);

        task->next = NULL;

        ngx_spinlock(&ngx_thread_pool_done_lock, 1, 2048);

        *ngx_thread_pool_done.last = task;
        ngx_thread_pool_done.last = &task->next;

        ngx_memory_barrier();

        ngx_unlock(&ngx_thread_pool_done_lock);

        (void) ngx_notify(ngx_thread_pool_handler);
    }
}


static void
ngx_thread_pool_handler(ngx_event_t *ev)
{
    ngx_event_t        *event;
    ngx_thread_task_t  *task;

    ngx_log_debug0(NGX_LOG_DEBUG_CORE, ev->log, 0, "thread pool handler");

    ngx_spinlock(&ngx_thread_pool_done_lock, 1, 2048);

    task = ngx_thread_pool_done.first;
    ngx_thread_pool_done.first = NULL;
    ngx_thread_pool_done.last = &ngx_thread_pool_done.first;

    ngx_memory_barrier();

    ngx_unlock(&ngx_thread_pool_done_lock);

    while (task) {
        ngx_log_debug1(NGX_LOG_DEBUG_CORE, ev->log, 0,
                       "run completion handler for task #%ui", task->id);

        event = &task->event;
        task = task->next;

        event->complete = 1;
        event->active = 0;

        event->handler(event);
    }
}


static void *
ngx_thread_pool_create_conf(ngx_cycle_t *cycle)
{
    ngx_thread_pool_conf_t  *tcf;

    tcf = ngx_pcalloc(cycle->pool, sizeof(ngx_thread_pool_conf_t));
    if (tcf == NULL) {
        return NULL;
    }

    if (ngx_array_init(&tcf->pools, cycle->pool, 4,
                       sizeof(ngx_thread_pool_t *))
        != NGX_OK)
    {
        return NULL;
    }

    return tcf;
}


static char *
ngx_thread_pool_init_conf(ngx_cycle_t *cycle, void *conf)
{
    ngx_thread_pool_conf_t *tcf = conf;

    ngx_uint_t           i;
    ngx_thread_pool_t  **tpp;

    tpp = tcf->pools.elts;

    for (i = 0; i < tcf->pools.nelts; i++) {

        if (tpp[i]->threads) {
            continue;
        }

        if (tpp[i]->name.len == ngx_thread_pool_default.len
            && ngx_strncmp(tpp[i]->name.data, ngx_thread_pool_default.data,
                           ngx_thread_pool_default.len)
               == 0)
        {
            tpp[i]->threads = 32;
            tpp[i]->max_queue = 65536;
            continue;
        }

        ngx_log_error(NGX_LOG_EMERG, cycle->log, 0,
                      "unknown thread pool \"%V\" in %s:%ui",
                      &tpp[i]->name, tpp[i]->file, tpp[i]->line);

        return NGX_CONF_ERROR;
    }

    return NGX_CONF_OK;
}


static char *
ngx_thread_pool(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
{
    ngx_str_t          *value;
    ngx_uint_t          i;
    ngx_thread_pool_t  *tp;

    value = cf->args->elts;

    tp = ngx_thread_pool_add(cf, &value[1]);

    if (tp == NULL) {
        return NGX_CONF_ERROR;
    }

    if (tp->threads) {
        ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                           "duplicate thread pool \"%V\"", &tp->name);
        return NGX_CONF_ERROR;
    }

    tp->max_queue = 65536;

    for (i = 2; i < cf->args->nelts; i++) {

        if (ngx_strncmp(value[i].data, "threads=", 8) == 0) {

            tp->threads = ngx_atoi(value[i].data + 8, value[i].len - 8);

            if (tp->threads == (ngx_uint_t) NGX_ERROR || tp->threads == 0) {
                ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                                   "invalid threads value \"%V\"", &value[i]);
                return NGX_CONF_ERROR;
            }

            continue;
        }

        if (ngx_strncmp(value[i].data, "max_queue=", 10) == 0) {

            tp->max_queue = ngx_atoi(value[i].data + 10, value[i].len - 10);

            if (tp->max_queue == NGX_ERROR) {
                ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                                   "invalid max_queue value \"%V\"", &value[i]);
                return NGX_CONF_ERROR;
            }

            continue;
        }
    }

    if (tp->threads == 0) {
        ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                           "\"%V\" must have \"threads\" parameter",
                           &cmd->name);
        return NGX_CONF_ERROR;
    }

    return NGX_CONF_OK;
}


ngx_thread_pool_t *
ngx_thread_pool_add(ngx_conf_t *cf, ngx_str_t *name)
{
    ngx_thread_pool_t       *tp, **tpp;
    ngx_thread_pool_conf_t  *tcf;

    if (name == NULL) {
        name = &ngx_thread_pool_default;
    }

    tp = ngx_thread_pool_get(cf->cycle, name);

    if (tp) {
        return tp;
    }

    tp = ngx_pcalloc(cf->pool, sizeof(ngx_thread_pool_t));
    if (tp == NULL) {
        return NULL;
    }

    tp->name = *name;
    tp->file = cf->conf_file->file.name.data;
    tp->line = cf->conf_file->line;

    tcf = (ngx_thread_pool_conf_t *) ngx_get_conf(cf->cycle->conf_ctx,
                                                  ngx_thread_pool_module);

    tpp = ngx_array_push(&tcf->pools);
    if (tpp == NULL) {
        return NULL;
    }

    *tpp = tp;

    return tp;
}


ngx_thread_pool_t *
ngx_thread_pool_get(ngx_cycle_t *cycle, ngx_str_t *name)
{
    ngx_uint_t                i;
    ngx_thread_pool_t       **tpp;
    ngx_thread_pool_conf_t   *tcf;

    tcf = (ngx_thread_pool_conf_t *) ngx_get_conf(cycle->conf_ctx,
                                                  ngx_thread_pool_module);

    tpp = tcf->pools.elts;

    for (i = 0; i < tcf->pools.nelts; i++) {

        if (tpp[i]->name.len == name->len
            && ngx_strncmp(tpp[i]->name.data, name->data, name->len) == 0)
        {
            return tpp[i];
        }
    }

    return NULL;
}


static ngx_int_t
ngx_thread_pool_init_worker(ngx_cycle_t *cycle)
{
    ngx_uint_t                i;
    ngx_thread_pool_t       **tpp;
    ngx_thread_pool_conf_t   *tcf;

    if (ngx_process != NGX_PROCESS_WORKER
        && ngx_process != NGX_PROCESS_SINGLE)
    {
        return NGX_OK;
    }

    tcf = (ngx_thread_pool_conf_t *) ngx_get_conf(cycle->conf_ctx,
                                                  ngx_thread_pool_module);

    if (tcf == NULL) {
        return NGX_OK;
    }

    ngx_thread_pool_queue_init(&ngx_thread_pool_done);

    tpp = tcf->pools.elts;

    for (i = 0; i < tcf->pools.nelts; i++) {
        if (ngx_thread_pool_init(tpp[i], cycle->log, cycle->pool) != NGX_OK) {
            return NGX_ERROR;
        }
    }

    return NGX_OK;
}


static void
ngx_thread_pool_exit_worker(ngx_cycle_t *cycle)
{
    ngx_uint_t                i;
    ngx_thread_pool_t       **tpp;
    ngx_thread_pool_conf_t   *tcf;

    if (ngx_process != NGX_PROCESS_WORKER
        && ngx_process != NGX_PROCESS_SINGLE)
    {
        return;
    }

    tcf = (ngx_thread_pool_conf_t *) ngx_get_conf(cycle->conf_ctx,
                                                  ngx_thread_pool_module);

    if (tcf == NULL) {
        return;
    }

    tpp = tcf->pools.elts;

    for (i = 0; i < tcf->pools.nelts; i++) {
        ngx_thread_pool_destroy(tpp[i]);
    }
}

ngx_syslog.{h,c}

typedef struct {
    ngx_pool_t       *pool;
    ngx_uint_t        facility;
    ngx_uint_t        severity;
    ngx_str_t         tag;

    ngx_addr_t        server;
    ngx_connection_t  conn;
    unsigned          busy:1;
    unsigned          nohostname:1;
} ngx_syslog_peer_t;

char *ngx_syslog_process_conf(ngx_conf_t *cf, ngx_syslog_peer_t *peer);
u_char *ngx_syslog_add_header(ngx_syslog_peer_t *peer, u_char *buf);
void ngx_syslog_writer(ngx_log_t *log, ngx_uint_t level, u_char *buf,
    size_t len);
ssize_t ngx_syslog_send(ngx_syslog_peer_t *peer, u_char *buf, size_t len);