Klaus Demo nginx / 38196b8 src / event / modules / ngx_win32_select_module.c
38196b8

Tree @38196b8 (Download .tar.gz)

ngx_win32_select_module.c @38196b8raw · history · blame

  1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
/*
 * Copyright (C) Igor Sysoev
 * Copyright (C) Nginx, Inc.
 */


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


static ngx_int_t ngx_select_init(ngx_cycle_t *cycle, ngx_msec_t timer);
static void ngx_select_done(ngx_cycle_t *cycle);
static ngx_int_t ngx_select_add_event(ngx_event_t *ev, ngx_int_t event,
    ngx_uint_t flags);
static ngx_int_t ngx_select_del_event(ngx_event_t *ev, ngx_int_t event,
    ngx_uint_t flags);
static ngx_int_t ngx_select_process_events(ngx_cycle_t *cycle, ngx_msec_t timer,
    ngx_uint_t flags);
static void ngx_select_repair_fd_sets(ngx_cycle_t *cycle);
static char *ngx_select_init_conf(ngx_cycle_t *cycle, void *conf);


static fd_set         master_read_fd_set;
static fd_set         master_write_fd_set;
static fd_set         work_read_fd_set;
static fd_set         work_write_fd_set;
static fd_set         work_except_fd_set;

static ngx_uint_t     max_read;
static ngx_uint_t     max_write;
static ngx_uint_t     nevents;

static ngx_event_t  **event_index;


static ngx_str_t           select_name = ngx_string("select");

static ngx_event_module_t  ngx_select_module_ctx = {
    &select_name,
    NULL,                                  /* create configuration */
    ngx_select_init_conf,                  /* init configuration */

    {
        ngx_select_add_event,              /* add an event */
        ngx_select_del_event,              /* delete an event */
        ngx_select_add_event,              /* enable an event */
        ngx_select_del_event,              /* disable an event */
        NULL,                              /* add an connection */
        NULL,                              /* delete an connection */
        NULL,                              /* trigger a notify */
        ngx_select_process_events,         /* process the events */
        ngx_select_init,                   /* init the events */
        ngx_select_done                    /* done the events */
    }

};

ngx_module_t  ngx_select_module = {
    NGX_MODULE_V1,
    &ngx_select_module_ctx,                /* module context */
    NULL,                                  /* module directives */
    NGX_EVENT_MODULE,                      /* module type */
    NULL,                                  /* init master */
    NULL,                                  /* init module */
    NULL,                                  /* init process */
    NULL,                                  /* init thread */
    NULL,                                  /* exit thread */
    NULL,                                  /* exit process */
    NULL,                                  /* exit master */
    NGX_MODULE_V1_PADDING
};


static ngx_int_t
ngx_select_init(ngx_cycle_t *cycle, ngx_msec_t timer)
{
    ngx_event_t  **index;

    if (event_index == NULL) {
        FD_ZERO(&master_read_fd_set);
        FD_ZERO(&master_write_fd_set);
        nevents = 0;
    }

    if (ngx_process >= NGX_PROCESS_WORKER
        || cycle->old_cycle == NULL
        || cycle->old_cycle->connection_n < cycle->connection_n)
    {
        index = ngx_alloc(sizeof(ngx_event_t *) * 2 * cycle->connection_n,
                          cycle->log);
        if (index == NULL) {
            return NGX_ERROR;
        }

        if (event_index) {
            ngx_memcpy(index, event_index, sizeof(ngx_event_t *) * nevents);
            ngx_free(event_index);
        }

        event_index = index;
    }

    ngx_io = ngx_os_io;

    ngx_event_actions = ngx_select_module_ctx.actions;

    ngx_event_flags = NGX_USE_LEVEL_EVENT;

    max_read = 0;
    max_write = 0;

    return NGX_OK;
}


static void
ngx_select_done(ngx_cycle_t *cycle)
{
    ngx_free(event_index);

    event_index = NULL;
}


static ngx_int_t
ngx_select_add_event(ngx_event_t *ev, ngx_int_t event, ngx_uint_t flags)
{
    ngx_connection_t  *c;

    c = ev->data;

    ngx_log_debug2(NGX_LOG_DEBUG_EVENT, ev->log, 0,
                   "select add event fd:%d ev:%i", c->fd, event);

    if (ev->index != NGX_INVALID_INDEX) {
        ngx_log_error(NGX_LOG_ALERT, ev->log, 0,
                      "select event fd:%d ev:%i is already set", c->fd, event);
        return NGX_OK;
    }

    if ((event == NGX_READ_EVENT && ev->write)
        || (event == NGX_WRITE_EVENT && !ev->write))
    {
        ngx_log_error(NGX_LOG_ALERT, ev->log, 0,
                      "invalid select %s event fd:%d ev:%i",
                      ev->write ? "write" : "read", c->fd, event);
        return NGX_ERROR;
    }

    if ((event == NGX_READ_EVENT && max_read >= FD_SETSIZE)
        || (event == NGX_WRITE_EVENT && max_write >= FD_SETSIZE))
    {
        ngx_log_error(NGX_LOG_ERR, ev->log, 0,
                      "maximum number of descriptors "
                      "supported by select() is %d", FD_SETSIZE);
        return NGX_ERROR;
    }

    if (event == NGX_READ_EVENT) {
        FD_SET(c->fd, &master_read_fd_set);
        max_read++;

    } else if (event == NGX_WRITE_EVENT) {
        FD_SET(c->fd, &master_write_fd_set);
        max_write++;
    }

    ev->active = 1;

    event_index[nevents] = ev;
    ev->index = nevents;
    nevents++;

    return NGX_OK;
}


static ngx_int_t
ngx_select_del_event(ngx_event_t *ev, ngx_int_t event, ngx_uint_t flags)
{
    ngx_event_t       *e;
    ngx_connection_t  *c;

    c = ev->data;

    ev->active = 0;

    if (ev->index == NGX_INVALID_INDEX) {
        return NGX_OK;
    }

    ngx_log_debug2(NGX_LOG_DEBUG_EVENT, ev->log, 0,
                   "select del event fd:%d ev:%i", c->fd, event);

    if (event == NGX_READ_EVENT) {
        FD_CLR(c->fd, &master_read_fd_set);
        max_read--;

    } else if (event == NGX_WRITE_EVENT) {
        FD_CLR(c->fd, &master_write_fd_set);
        max_write--;
    }

    if (ev->index < --nevents) {
        e = event_index[nevents];
        event_index[ev->index] = e;
        e->index = ev->index;
    }

    ev->index = NGX_INVALID_INDEX;

    return NGX_OK;
}


static ngx_int_t
ngx_select_process_events(ngx_cycle_t *cycle, ngx_msec_t timer,
    ngx_uint_t flags)
{
    int                ready, nready;
    ngx_err_t          err;
    ngx_uint_t         i, found;
    ngx_event_t       *ev;
    ngx_queue_t       *queue;
    struct timeval     tv, *tp;
    ngx_connection_t  *c;

#if (NGX_DEBUG)
    if (cycle->log->log_level & NGX_LOG_DEBUG_ALL) {
        for (i = 0; i < nevents; i++) {
            ev = event_index[i];
            c = ev->data;
            ngx_log_debug2(NGX_LOG_DEBUG_EVENT, cycle->log, 0,
                           "select event: fd:%d wr:%d", c->fd, ev->write);
        }
    }
#endif

    if (timer == NGX_TIMER_INFINITE) {
        tp = NULL;

    } else {
        tv.tv_sec = (long) (timer / 1000);
        tv.tv_usec = (long) ((timer % 1000) * 1000);
        tp = &tv;
    }

    ngx_log_debug1(NGX_LOG_DEBUG_EVENT, cycle->log, 0,
                   "select timer: %M", timer);

    work_read_fd_set = master_read_fd_set;
    work_write_fd_set = master_write_fd_set;
    work_except_fd_set = master_write_fd_set;

    if (max_read || max_write) {
        ready = select(0, &work_read_fd_set, &work_write_fd_set,
                       &work_except_fd_set, tp);

    } else {

        /*
         * Winsock select() requires that at least one descriptor set must be
         * be non-null, and any non-null descriptor set must contain at least
         * one handle to a socket.  Otherwise select() returns WSAEINVAL.
         */

        ngx_msleep(timer);

        ready = 0;
    }

    err = (ready == -1) ? ngx_socket_errno : 0;

    if (flags & NGX_UPDATE_TIME) {
        ngx_time_update();
    }

    ngx_log_debug1(NGX_LOG_DEBUG_EVENT, cycle->log, 0,
                   "select ready %d", ready);

    if (err) {
        ngx_log_error(NGX_LOG_ALERT, cycle->log, err, "select() failed");

        if (err == WSAENOTSOCK) {
            ngx_select_repair_fd_sets(cycle);
        }

        return NGX_ERROR;
    }

    if (ready == 0) {
        if (timer != NGX_TIMER_INFINITE) {
            return NGX_OK;
        }

        ngx_log_error(NGX_LOG_ALERT, cycle->log, 0,
                      "select() returned no events without timeout");
        return NGX_ERROR;
    }

    nready = 0;

    for (i = 0; i < nevents; i++) {
        ev = event_index[i];
        c = ev->data;
        found = 0;

        if (ev->write) {
            if (FD_ISSET(c->fd, &work_write_fd_set)) {
                found++;
                ngx_log_debug1(NGX_LOG_DEBUG_EVENT, cycle->log, 0,
                               "select write %d", c->fd);
            }

            if (FD_ISSET(c->fd, &work_except_fd_set)) {
                found++;
                ngx_log_debug1(NGX_LOG_DEBUG_EVENT, cycle->log, 0,
                               "select except %d", c->fd);
            }

        } else {
            if (FD_ISSET(c->fd, &work_read_fd_set)) {
                found++;
                ngx_log_debug1(NGX_LOG_DEBUG_EVENT, cycle->log, 0,
                               "select read %d", c->fd);
            }
        }

        if (found) {
            ev->ready = 1;

            queue = ev->accept ? &ngx_posted_accept_events
                               : &ngx_posted_events;

            ngx_post_event(ev, queue);

            nready += found;
        }
    }

    if (ready != nready) {
        ngx_log_error(NGX_LOG_ALERT, cycle->log, 0,
                      "select ready != events: %d:%d", ready, nready);

        ngx_select_repair_fd_sets(cycle);
    }

    return NGX_OK;
}


static void
ngx_select_repair_fd_sets(ngx_cycle_t *cycle)
{
    int           n;
    u_int         i;
    socklen_t     len;
    ngx_err_t     err;
    ngx_socket_t  s;

    for (i = 0; i < master_read_fd_set.fd_count; i++) {

        s = master_read_fd_set.fd_array[i];
        len = sizeof(int);

        if (getsockopt(s, SOL_SOCKET, SO_TYPE, (char *) &n, &len) == -1) {
            err = ngx_socket_errno;

            ngx_log_error(NGX_LOG_ALERT, cycle->log, err,
                          "invalid descriptor #%d in read fd_set", s);

            FD_CLR(s, &master_read_fd_set);
        }
    }

    for (i = 0; i < master_write_fd_set.fd_count; i++) {

        s = master_write_fd_set.fd_array[i];
        len = sizeof(int);

        if (getsockopt(s, SOL_SOCKET, SO_TYPE, (char *) &n, &len) == -1) {
            err = ngx_socket_errno;

            ngx_log_error(NGX_LOG_ALERT, cycle->log, err,
                          "invalid descriptor #%d in write fd_set", s);

            FD_CLR(s, &master_write_fd_set);
        }
    }
}


static char *
ngx_select_init_conf(ngx_cycle_t *cycle, void *conf)
{
    ngx_event_conf_t  *ecf;

    ecf = ngx_event_get_conf(cycle->conf_ctx, ngx_event_core_module);

    if (ecf->use != ngx_select_module.ctx_index) {
        return NGX_CONF_OK;
    }

    return NGX_CONF_OK;
}