view src/event/ngx_event.h @ 8122:106328a70f4e

Added warning about redefinition of listen socket protocol options. The "listen" directive in the http module can be used multiple times in different server blocks. Originally, it was supposed to be specified once with various socket options, and without any parameters in virtual server blocks. For example: server { listen 80 backlog=1024; server_name foo; ... } server { listen 80; server_name bar; ... } server { listen 80; server_name bazz; ... } The address part of the syntax ("address[:port]" / "port" / "unix:path") uniquely identifies the listening socket, and therefore is enough for name-based virtual servers (to let nginx know that the virtual server accepts requests on the listening socket in question). To ensure that listening options do not conflict between virtual servers, they were allowed only once. For example, the following configuration will be rejected ("duplicate listen options for 0.0.0.0:80 in ..."): server { listen 80 backlog=1024; server_name foo; ... } server { listen 80 backlog=512; server_name bar; ... } At some point it was, however, noticed, that it is sometimes convenient to repeat some options for clarity. In nginx 0.8.51 the "ssl" parameter was allowed to be specified multiple times, e.g.: server { listen 443 ssl backlog=1024; server_name foo; ... } server { listen 443 ssl; server_name bar; ... } server { listen 443 ssl; server_name bazz; ... } This approach makes configuration more readable, since SSL sockets are immediately visible in the configuration. If this is not needed, just the address can still be used. Later, additional protocol-specific options similar to "ssl" were introduced, notably "http2" and "proxy_protocol". With these options, one can write: server { listen 443 ssl backlog=1024; server_name foo; ... } server { listen 443 http2; server_name bar; ... } server { listen 443 proxy_protocol; server_name bazz; ... } The resulting socket will use ssl, http2, and proxy_protocol, but this is not really obvious from the configuration. To emphasize such misleading configurations are discouraged, nginx now warns as long as the "listen" directive is used with options different from the options previously used if this is potentially confusing. In particular, the following configurations are allowed: server { listen 8401 ssl backlog=1024; server_name foo; } server { listen 8401 ssl; server_name bar; } server { listen 8401 ssl; server_name bazz; } server { listen 8402 ssl http2 backlog=1024; server_name foo; } server { listen 8402 ssl; server_name bar; } server { listen 8402 ssl; server_name bazz; } server { listen 8403 ssl; server_name bar; } server { listen 8403 ssl; server_name bazz; } server { listen 8403 ssl http2; server_name foo; } server { listen 8404 ssl http2 backlog=1024; server_name foo; } server { listen 8404 http2; server_name bar; } server { listen 8404 http2; server_name bazz; } server { listen 8405 ssl http2 backlog=1024; server_name foo; } server { listen 8405 ssl http2; server_name bar; } server { listen 8405 ssl http2; server_name bazz; } server { listen 8406 ssl; server_name foo; } server { listen 8406; server_name bar; } server { listen 8406; server_name bazz; } And the following configurations will generate warnings: server { listen 8501 ssl http2 backlog=1024; server_name foo; } server { listen 8501 http2; server_name bar; } server { listen 8501 ssl; server_name bazz; } server { listen 8502 backlog=1024; server_name foo; } server { listen 8502 ssl; server_name bar; } server { listen 8503 ssl; server_name foo; } server { listen 8503 http2; server_name bar; } server { listen 8504 ssl; server_name foo; } server { listen 8504 http2; server_name bar; } server { listen 8504 proxy_protocol; server_name bazz; } server { listen 8505 ssl http2 proxy_protocol; server_name foo; } server { listen 8505 ssl http2; server_name bar; } server { listen 8505 ssl; server_name bazz; } server { listen 8506 ssl http2; server_name foo; } server { listen 8506 ssl; server_name bar; } server { listen 8506; server_name bazz; } server { listen 8507 ssl; server_name bar; } server { listen 8507; server_name bazz; } server { listen 8507 ssl http2; server_name foo; } server { listen 8508 ssl; server_name bar; } server { listen 8508; server_name bazz; } server { listen 8508 ssl backlog=1024; server_name foo; } server { listen 8509; server_name bazz; } server { listen 8509 ssl; server_name bar; } server { listen 8509 ssl backlog=1024; server_name foo; } The basic idea is that at most two sets of protocol options are allowed: the main one (with socket options, if any), and a shorter one, with options being a subset of the main options, repeated for clarity. As long as the shorter set of protocol options is used, all listen directives except the main one should use it.
author Maxim Dounin <mdounin@mdounin.ru>
date Sat, 28 Jan 2023 01:29:45 +0300
parents 8206ecdcd837
children ce6d9cf0f567
line wrap: on
line source


/*
 * Copyright (C) Igor Sysoev
 * Copyright (C) Nginx, Inc.
 */


#ifndef _NGX_EVENT_H_INCLUDED_
#define _NGX_EVENT_H_INCLUDED_


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


#define NGX_INVALID_INDEX  0xd0d0d0d0


#if (NGX_HAVE_IOCP)

typedef struct {
    WSAOVERLAPPED    ovlp;
    ngx_event_t     *event;
    int              error;
} ngx_event_ovlp_t;

#endif


struct ngx_event_s {
    void            *data;

    unsigned         write:1;

    unsigned         accept:1;

    /* used to detect the stale events in kqueue and epoll */
    unsigned         instance:1;

    /*
     * the event was passed or would be passed to a kernel;
     * in aio mode - operation was posted.
     */
    unsigned         active:1;

    unsigned         disabled:1;

    /* the ready event; in aio mode 0 means that no operation can be posted */
    unsigned         ready:1;

    unsigned         oneshot:1;

    /* aio operation is complete */
    unsigned         complete:1;

    unsigned         eof:1;
    unsigned         error:1;

    unsigned         timedout:1;
    unsigned         timer_set:1;

    unsigned         delayed:1;

    unsigned         deferred_accept:1;

    /* the pending eof reported by kqueue, epoll or in aio chain operation */
    unsigned         pending_eof:1;

    unsigned         posted:1;

    unsigned         closed:1;

    /* to test on worker exit */
    unsigned         channel:1;
    unsigned         resolver:1;

    unsigned         cancelable:1;

#if (NGX_HAVE_KQUEUE)
    unsigned         kq_vnode:1;

    /* the pending errno reported by kqueue */
    int              kq_errno;
#endif

    /*
     * kqueue only:
     *   accept:     number of sockets that wait to be accepted
     *   read:       bytes to read when event is ready
     *               or lowat when event is set with NGX_LOWAT_EVENT flag
     *   write:      available space in buffer when event is ready
     *               or lowat when event is set with NGX_LOWAT_EVENT flag
     *
     * iocp: TODO
     *
     * otherwise:
     *   accept:     1 if accept many, 0 otherwise
     *   read:       bytes to read when event is ready, -1 if not known
     */

    int              available;

    ngx_event_handler_pt  handler;


#if (NGX_HAVE_IOCP)
    ngx_event_ovlp_t ovlp;
#endif

    ngx_uint_t       index;

    ngx_log_t       *log;

    ngx_rbtree_node_t   timer;

    /* the posted queue */
    ngx_queue_t      queue;

#if 0

    /* the threads support */

    /*
     * the event thread context, we store it here
     * if $(CC) does not understand __thread declaration
     * and pthread_getspecific() is too costly
     */

    void            *thr_ctx;

#if (NGX_EVENT_T_PADDING)

    /* event should not cross cache line in SMP */

    uint32_t         padding[NGX_EVENT_T_PADDING];
#endif
#endif
};


#if (NGX_HAVE_FILE_AIO)

struct ngx_event_aio_s {
    void                      *data;
    ngx_event_handler_pt       handler;
    ngx_file_t                *file;

    ngx_fd_t                   fd;

#if (NGX_HAVE_EVENTFD)
    int64_t                    res;
#endif

#if !(NGX_HAVE_EVENTFD) || (NGX_TEST_BUILD_EPOLL)
    ngx_err_t                  err;
    size_t                     nbytes;
#endif

    ngx_aiocb_t                aiocb;
    ngx_event_t                event;
};

#endif


typedef struct {
    ngx_int_t  (*add)(ngx_event_t *ev, ngx_int_t event, ngx_uint_t flags);
    ngx_int_t  (*del)(ngx_event_t *ev, ngx_int_t event, ngx_uint_t flags);

    ngx_int_t  (*enable)(ngx_event_t *ev, ngx_int_t event, ngx_uint_t flags);
    ngx_int_t  (*disable)(ngx_event_t *ev, ngx_int_t event, ngx_uint_t flags);

    ngx_int_t  (*add_conn)(ngx_connection_t *c);
    ngx_int_t  (*del_conn)(ngx_connection_t *c, ngx_uint_t flags);

    ngx_int_t  (*notify)(ngx_event_handler_pt handler);

    ngx_int_t  (*process_events)(ngx_cycle_t *cycle, ngx_msec_t timer,
                                 ngx_uint_t flags);

    ngx_int_t  (*init)(ngx_cycle_t *cycle, ngx_msec_t timer);
    void       (*done)(ngx_cycle_t *cycle);
} ngx_event_actions_t;


extern ngx_event_actions_t   ngx_event_actions;
#if (NGX_HAVE_EPOLLRDHUP)
extern ngx_uint_t            ngx_use_epoll_rdhup;
#endif


/*
 * The event filter requires to read/write the whole data:
 * select, poll, /dev/poll, kqueue, epoll.
 */
#define NGX_USE_LEVEL_EVENT      0x00000001

/*
 * The event filter is deleted after a notification without an additional
 * syscall: kqueue, epoll.
 */
#define NGX_USE_ONESHOT_EVENT    0x00000002

/*
 * The event filter notifies only the changes and an initial level:
 * kqueue, epoll.
 */
#define NGX_USE_CLEAR_EVENT      0x00000004

/*
 * The event filter has kqueue features: the eof flag, errno,
 * available data, etc.
 */
#define NGX_USE_KQUEUE_EVENT     0x00000008

/*
 * The event filter supports low water mark: kqueue's NOTE_LOWAT.
 * kqueue in FreeBSD 4.1-4.2 has no NOTE_LOWAT so we need a separate flag.
 */
#define NGX_USE_LOWAT_EVENT      0x00000010

/*
 * The event filter requires to do i/o operation until EAGAIN: epoll.
 */
#define NGX_USE_GREEDY_EVENT     0x00000020

/*
 * The event filter is epoll.
 */
#define NGX_USE_EPOLL_EVENT      0x00000040

/*
 * Obsolete.
 */
#define NGX_USE_RTSIG_EVENT      0x00000080

/*
 * Obsolete.
 */
#define NGX_USE_AIO_EVENT        0x00000100

/*
 * Need to add socket or handle only once: i/o completion port.
 */
#define NGX_USE_IOCP_EVENT       0x00000200

/*
 * The event filter has no opaque data and requires file descriptors table:
 * poll, /dev/poll.
 */
#define NGX_USE_FD_EVENT         0x00000400

/*
 * The event module handles periodic or absolute timer event by itself:
 * kqueue in FreeBSD 4.4, NetBSD 2.0, and MacOSX 10.4, Solaris 10's event ports.
 */
#define NGX_USE_TIMER_EVENT      0x00000800

/*
 * All event filters on file descriptor are deleted after a notification:
 * Solaris 10's event ports.
 */
#define NGX_USE_EVENTPORT_EVENT  0x00001000

/*
 * The event filter support vnode notifications: kqueue.
 */
#define NGX_USE_VNODE_EVENT      0x00002000


/*
 * The event filter is deleted just before the closing file.
 * Has no meaning for select and poll.
 * kqueue, epoll, eventport:         allows to avoid explicit delete,
 *                                   because filter automatically is deleted
 *                                   on file close,
 *
 * /dev/poll:                        we need to flush POLLREMOVE event
 *                                   before closing file.
 */
#define NGX_CLOSE_EVENT    1

/*
 * disable temporarily event filter, this may avoid locks
 * in kernel malloc()/free(): kqueue.
 */
#define NGX_DISABLE_EVENT  2

/*
 * event must be passed to kernel right now, do not wait until batch processing.
 */
#define NGX_FLUSH_EVENT    4


/* these flags have a meaning only for kqueue */
#define NGX_LOWAT_EVENT    0
#define NGX_VNODE_EVENT    0


#if (NGX_HAVE_EPOLL) && !(NGX_HAVE_EPOLLRDHUP)
#define EPOLLRDHUP         0
#endif


#if (NGX_HAVE_KQUEUE)

#define NGX_READ_EVENT     EVFILT_READ
#define NGX_WRITE_EVENT    EVFILT_WRITE

#undef  NGX_VNODE_EVENT
#define NGX_VNODE_EVENT    EVFILT_VNODE

/*
 * NGX_CLOSE_EVENT, NGX_LOWAT_EVENT, and NGX_FLUSH_EVENT are the module flags
 * and they must not go into a kernel so we need to choose the value
 * that must not interfere with any existent and future kqueue flags.
 * kqueue has such values - EV_FLAG1, EV_EOF, and EV_ERROR:
 * they are reserved and cleared on a kernel entrance.
 */
#undef  NGX_CLOSE_EVENT
#define NGX_CLOSE_EVENT    EV_EOF

#undef  NGX_LOWAT_EVENT
#define NGX_LOWAT_EVENT    EV_FLAG1

#undef  NGX_FLUSH_EVENT
#define NGX_FLUSH_EVENT    EV_ERROR

#define NGX_LEVEL_EVENT    0
#define NGX_ONESHOT_EVENT  EV_ONESHOT
#define NGX_CLEAR_EVENT    EV_CLEAR

#undef  NGX_DISABLE_EVENT
#define NGX_DISABLE_EVENT  EV_DISABLE


#elif (NGX_HAVE_DEVPOLL && !(NGX_TEST_BUILD_DEVPOLL)) \
      || (NGX_HAVE_EVENTPORT && !(NGX_TEST_BUILD_EVENTPORT))

#define NGX_READ_EVENT     POLLIN
#define NGX_WRITE_EVENT    POLLOUT

#define NGX_LEVEL_EVENT    0
#define NGX_ONESHOT_EVENT  1


#elif (NGX_HAVE_EPOLL) && !(NGX_TEST_BUILD_EPOLL)

#define NGX_READ_EVENT     (EPOLLIN|EPOLLRDHUP)
#define NGX_WRITE_EVENT    EPOLLOUT

#define NGX_LEVEL_EVENT    0
#define NGX_CLEAR_EVENT    EPOLLET
#define NGX_ONESHOT_EVENT  0x70000000
#if 0
#define NGX_ONESHOT_EVENT  EPOLLONESHOT
#endif

#if (NGX_HAVE_EPOLLEXCLUSIVE)
#define NGX_EXCLUSIVE_EVENT  EPOLLEXCLUSIVE
#endif

#elif (NGX_HAVE_POLL)

#define NGX_READ_EVENT     POLLIN
#define NGX_WRITE_EVENT    POLLOUT

#define NGX_LEVEL_EVENT    0
#define NGX_ONESHOT_EVENT  1


#else /* select */

#define NGX_READ_EVENT     0
#define NGX_WRITE_EVENT    1

#define NGX_LEVEL_EVENT    0
#define NGX_ONESHOT_EVENT  1

#endif /* NGX_HAVE_KQUEUE */


#if (NGX_HAVE_IOCP)
#define NGX_IOCP_ACCEPT      0
#define NGX_IOCP_IO          1
#define NGX_IOCP_CONNECT     2
#endif


#if (NGX_TEST_BUILD_EPOLL)
#define NGX_EXCLUSIVE_EVENT  0
#endif


#ifndef NGX_CLEAR_EVENT
#define NGX_CLEAR_EVENT    0    /* dummy declaration */
#endif


#define ngx_process_events   ngx_event_actions.process_events
#define ngx_done_events      ngx_event_actions.done

#define ngx_add_event        ngx_event_actions.add
#define ngx_del_event        ngx_event_actions.del
#define ngx_add_conn         ngx_event_actions.add_conn
#define ngx_del_conn         ngx_event_actions.del_conn

#define ngx_notify           ngx_event_actions.notify

#define ngx_add_timer        ngx_event_add_timer
#define ngx_del_timer        ngx_event_del_timer


extern ngx_os_io_t  ngx_io;

#define ngx_recv             ngx_io.recv
#define ngx_recv_chain       ngx_io.recv_chain
#define ngx_udp_recv         ngx_io.udp_recv
#define ngx_send             ngx_io.send
#define ngx_send_chain       ngx_io.send_chain
#define ngx_udp_send         ngx_io.udp_send
#define ngx_udp_send_chain   ngx_io.udp_send_chain


#define NGX_EVENT_MODULE      0x544E5645  /* "EVNT" */
#define NGX_EVENT_CONF        0x02000000


typedef struct {
    ngx_uint_t    connections;
    ngx_uint_t    use;

    ngx_flag_t    multi_accept;
    ngx_flag_t    accept_mutex;

    ngx_msec_t    accept_mutex_delay;

    u_char       *name;

#if (NGX_DEBUG)
    ngx_array_t   debug_connection;
#endif
} ngx_event_conf_t;


typedef struct {
    ngx_str_t              *name;

    void                 *(*create_conf)(ngx_cycle_t *cycle);
    char                 *(*init_conf)(ngx_cycle_t *cycle, void *conf);

    ngx_event_actions_t     actions;
} ngx_event_module_t;


extern ngx_atomic_t          *ngx_connection_counter;

extern ngx_atomic_t          *ngx_accept_mutex_ptr;
extern ngx_shmtx_t            ngx_accept_mutex;
extern ngx_uint_t             ngx_use_accept_mutex;
extern ngx_uint_t             ngx_accept_events;
extern ngx_uint_t             ngx_accept_mutex_held;
extern ngx_msec_t             ngx_accept_mutex_delay;
extern ngx_int_t              ngx_accept_disabled;
extern ngx_uint_t             ngx_use_exclusive_accept;


#if (NGX_STAT_STUB)

extern ngx_atomic_t  *ngx_stat_accepted;
extern ngx_atomic_t  *ngx_stat_handled;
extern ngx_atomic_t  *ngx_stat_requests;
extern ngx_atomic_t  *ngx_stat_active;
extern ngx_atomic_t  *ngx_stat_reading;
extern ngx_atomic_t  *ngx_stat_writing;
extern ngx_atomic_t  *ngx_stat_waiting;

#endif


#define NGX_UPDATE_TIME         1
#define NGX_POST_EVENTS         2


extern sig_atomic_t           ngx_event_timer_alarm;
extern ngx_uint_t             ngx_event_flags;
extern ngx_module_t           ngx_events_module;
extern ngx_module_t           ngx_event_core_module;


#define ngx_event_get_conf(conf_ctx, module)                                  \
             (*(ngx_get_conf(conf_ctx, ngx_events_module))) [module.ctx_index]



void ngx_event_accept(ngx_event_t *ev);
ngx_int_t ngx_trylock_accept_mutex(ngx_cycle_t *cycle);
ngx_int_t ngx_enable_accept_events(ngx_cycle_t *cycle);
u_char *ngx_accept_log_error(ngx_log_t *log, u_char *buf, size_t len);
#if (NGX_DEBUG)
void ngx_debug_accepted_connection(ngx_event_conf_t *ecf, ngx_connection_t *c);
#endif


void ngx_process_events_and_timers(ngx_cycle_t *cycle);
ngx_int_t ngx_handle_read_event(ngx_event_t *rev, ngx_uint_t flags);
ngx_int_t ngx_handle_write_event(ngx_event_t *wev, size_t lowat);


#if (NGX_WIN32)
void ngx_event_acceptex(ngx_event_t *ev);
ngx_int_t ngx_event_post_acceptex(ngx_listening_t *ls, ngx_uint_t n);
u_char *ngx_acceptex_log_error(ngx_log_t *log, u_char *buf, size_t len);
#endif


ngx_int_t ngx_send_lowat(ngx_connection_t *c, size_t lowat);


/* used in ngx_log_debugX() */
#define ngx_event_ident(p)  ((ngx_connection_t *) (p))->fd


#include <ngx_event_timer.h>
#include <ngx_event_posted.h>
#include <ngx_event_udp.h>

#if (NGX_WIN32)
#include <ngx_iocp_module.h>
#endif


#endif /* _NGX_EVENT_H_INCLUDED_ */