1/*
2 * Copyright 2007-2012 Niels Provos and Nick Mathewson
3 * Copyright 2000-2007 Niels Provos <provos@citi.umich.edu>
4 * Copyright 2003 Michael A. Davis <mike@datanerds.net>
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 *    notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 * 3. The name of the author may not be used to endorse or promote products
15 *    derived from this software without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 */
28#include "event2/event-config.h"
29#include "evconfig-private.h"
30
31#ifdef _WIN32
32
33#include <winsock2.h>
34#include <windows.h>
35#include <sys/types.h>
36#include <sys/queue.h>
37#include <limits.h>
38#include <signal.h>
39#include <stdio.h>
40#include <stdlib.h>
41#include <string.h>
42#include <errno.h>
43
44#include "event2/util.h"
45#include "util-internal.h"
46#include "log-internal.h"
47#include "event2/event.h"
48#include "event-internal.h"
49#include "evmap-internal.h"
50#include "event2/thread.h"
51#include "evthread-internal.h"
52#include "time-internal.h"
53
54#define XFREE(ptr) do { if (ptr) mm_free(ptr); } while (0)
55
56extern struct event_list timequeue;
57extern struct event_list addqueue;
58
59struct win_fd_set {
60	unsigned int fd_count;
61	SOCKET fd_array[1];
62};
63
64/* MSDN says this is required to handle SIGFPE */
65volatile double SIGFPE_REQ = 0.0f;
66
67struct idx_info {
68	int read_pos_plus1;
69	int write_pos_plus1;
70};
71
72struct win32op {
73	unsigned num_fds_in_fd_sets;
74	int resize_out_sets;
75	struct win_fd_set *readset_in;
76	struct win_fd_set *writeset_in;
77	struct win_fd_set *readset_out;
78	struct win_fd_set *writeset_out;
79	struct win_fd_set *exset_out;
80	unsigned signals_are_broken : 1;
81};
82
83static void *win32_init(struct event_base *);
84static int win32_add(struct event_base *, evutil_socket_t, short old, short events, void *idx_);
85static int win32_del(struct event_base *, evutil_socket_t, short old, short events, void *idx_);
86static int win32_dispatch(struct event_base *base, struct timeval *);
87static void win32_dealloc(struct event_base *);
88
89struct eventop win32ops = {
90	"win32",
91	win32_init,
92	win32_add,
93	win32_del,
94	win32_dispatch,
95	win32_dealloc,
96	0, /* doesn't need reinit */
97	0, /* No features supported. */
98	sizeof(struct idx_info),
99};
100
101#define FD_SET_ALLOC_SIZE(n) ((sizeof(struct win_fd_set) + ((n)-1)*sizeof(SOCKET)))
102
103static int
104grow_fd_sets(struct win32op *op, unsigned new_num_fds)
105{
106	size_t size;
107
108	EVUTIL_ASSERT(new_num_fds >= op->readset_in->fd_count &&
109	       new_num_fds >= op->writeset_in->fd_count);
110	EVUTIL_ASSERT(new_num_fds >= 1);
111
112	size = FD_SET_ALLOC_SIZE(new_num_fds);
113	if (!(op->readset_in = mm_realloc(op->readset_in, size)))
114		return (-1);
115	if (!(op->writeset_in = mm_realloc(op->writeset_in, size)))
116		return (-1);
117	op->resize_out_sets = 1;
118	op->num_fds_in_fd_sets = new_num_fds;
119	return (0);
120}
121
122static int
123do_fd_set(struct win32op *op, struct idx_info *ent, evutil_socket_t s, int read)
124{
125	struct win_fd_set *set = read ? op->readset_in : op->writeset_in;
126	if (read) {
127		if (ent->read_pos_plus1 > 0)
128			return (0);
129	} else {
130		if (ent->write_pos_plus1 > 0)
131			return (0);
132	}
133	if (set->fd_count == op->num_fds_in_fd_sets) {
134		if (grow_fd_sets(op, op->num_fds_in_fd_sets*2))
135			return (-1);
136		/* set pointer will have changed and needs reiniting! */
137		set = read ? op->readset_in : op->writeset_in;
138	}
139	set->fd_array[set->fd_count] = s;
140	if (read)
141		ent->read_pos_plus1 = set->fd_count+1;
142	else
143		ent->write_pos_plus1 = set->fd_count+1;
144	return (set->fd_count++);
145}
146
147static int
148do_fd_clear(struct event_base *base,
149			struct win32op *op, struct idx_info *ent, int read)
150{
151	int i;
152	struct win_fd_set *set = read ? op->readset_in : op->writeset_in;
153	if (read) {
154		i = ent->read_pos_plus1 - 1;
155		ent->read_pos_plus1 = 0;
156	} else {
157		i = ent->write_pos_plus1 - 1;
158		ent->write_pos_plus1 = 0;
159	}
160	if (i < 0)
161		return (0);
162	if (--set->fd_count != (unsigned)i) {
163		struct idx_info *ent2;
164		SOCKET s2;
165		s2 = set->fd_array[i] = set->fd_array[set->fd_count];
166
167		ent2 = evmap_io_get_fdinfo_(&base->io, s2);
168
169		if (!ent2) /* This indicates a bug. */
170			return (0);
171		if (read)
172			ent2->read_pos_plus1 = i+1;
173		else
174			ent2->write_pos_plus1 = i+1;
175	}
176	return (0);
177}
178
179#define NEVENT 32
180void *
181win32_init(struct event_base *base)
182{
183	struct win32op *winop;
184	size_t size;
185	if (!(winop = mm_calloc(1, sizeof(struct win32op))))
186		return NULL;
187	winop->num_fds_in_fd_sets = NEVENT;
188	size = FD_SET_ALLOC_SIZE(NEVENT);
189	if (!(winop->readset_in = mm_malloc(size)))
190		goto err;
191	if (!(winop->writeset_in = mm_malloc(size)))
192		goto err;
193	if (!(winop->readset_out = mm_malloc(size)))
194		goto err;
195	if (!(winop->writeset_out = mm_malloc(size)))
196		goto err;
197	if (!(winop->exset_out = mm_malloc(size)))
198		goto err;
199	winop->readset_in->fd_count = winop->writeset_in->fd_count = 0;
200	winop->readset_out->fd_count = winop->writeset_out->fd_count
201		= winop->exset_out->fd_count = 0;
202
203	if (evsig_init_(base) < 0)
204		winop->signals_are_broken = 1;
205
206	evutil_weakrand_seed_(&base->weakrand_seed, 0);
207
208	return (winop);
209 err:
210	XFREE(winop->readset_in);
211	XFREE(winop->writeset_in);
212	XFREE(winop->readset_out);
213	XFREE(winop->writeset_out);
214	XFREE(winop->exset_out);
215	XFREE(winop);
216	return (NULL);
217}
218
219int
220win32_add(struct event_base *base, evutil_socket_t fd,
221			 short old, short events, void *idx_)
222{
223	struct win32op *win32op = base->evbase;
224	struct idx_info *idx = idx_;
225
226	if ((events & EV_SIGNAL) && win32op->signals_are_broken)
227		return (-1);
228
229	if (!(events & (EV_READ|EV_WRITE)))
230		return (0);
231
232	event_debug(("%s: adding event for %d", __func__, (int)fd));
233	if (events & EV_READ) {
234		if (do_fd_set(win32op, idx, fd, 1)<0)
235			return (-1);
236	}
237	if (events & EV_WRITE) {
238		if (do_fd_set(win32op, idx, fd, 0)<0)
239			return (-1);
240	}
241	return (0);
242}
243
244int
245win32_del(struct event_base *base, evutil_socket_t fd, short old, short events,
246		  void *idx_)
247{
248	struct win32op *win32op = base->evbase;
249	struct idx_info *idx = idx_;
250
251	event_debug(("%s: Removing event for "EV_SOCK_FMT,
252		__func__, EV_SOCK_ARG(fd)));
253	if (events & EV_READ)
254		do_fd_clear(base, win32op, idx, 1);
255	if (events & EV_WRITE)
256		do_fd_clear(base, win32op, idx, 0);
257
258	return 0;
259}
260
261static void
262fd_set_copy(struct win_fd_set *out, const struct win_fd_set *in)
263{
264	out->fd_count = in->fd_count;
265	memcpy(out->fd_array, in->fd_array, in->fd_count * (sizeof(SOCKET)));
266}
267
268/*
269  static void dump_fd_set(struct win_fd_set *s)
270  {
271  unsigned int i;
272  printf("[ ");
273  for(i=0;i<s->fd_count;++i)
274  printf("%d ",(int)s->fd_array[i]);
275  printf("]\n");
276  }
277*/
278
279int
280win32_dispatch(struct event_base *base, struct timeval *tv)
281{
282	struct win32op *win32op = base->evbase;
283	int res = 0;
284	unsigned j, i;
285	int fd_count;
286	SOCKET s;
287
288	if (win32op->resize_out_sets) {
289		size_t size = FD_SET_ALLOC_SIZE(win32op->num_fds_in_fd_sets);
290		if (!(win32op->readset_out = mm_realloc(win32op->readset_out, size)))
291			return (-1);
292		if (!(win32op->exset_out = mm_realloc(win32op->exset_out, size)))
293			return (-1);
294		if (!(win32op->writeset_out = mm_realloc(win32op->writeset_out, size)))
295			return (-1);
296		win32op->resize_out_sets = 0;
297	}
298
299	fd_set_copy(win32op->readset_out, win32op->readset_in);
300	fd_set_copy(win32op->exset_out, win32op->writeset_in);
301	fd_set_copy(win32op->writeset_out, win32op->writeset_in);
302
303	fd_count =
304	    (win32op->readset_out->fd_count > win32op->writeset_out->fd_count) ?
305	    win32op->readset_out->fd_count : win32op->writeset_out->fd_count;
306
307	if (!fd_count) {
308		long msec = tv ? evutil_tv_to_msec_(tv) : LONG_MAX;
309		/* Sleep's DWORD argument is unsigned long */
310		if (msec < 0)
311			msec = LONG_MAX;
312		/* Windows doesn't like you to call select() with no sockets */
313		Sleep(msec);
314		return (0);
315	}
316
317	EVBASE_RELEASE_LOCK(base, th_base_lock);
318
319	res = select(fd_count,
320		     (struct fd_set*)win32op->readset_out,
321		     (struct fd_set*)win32op->writeset_out,
322		     (struct fd_set*)win32op->exset_out, tv);
323
324	EVBASE_ACQUIRE_LOCK(base, th_base_lock);
325
326	event_debug(("%s: select returned %d", __func__, res));
327
328	if (res <= 0) {
329		event_debug(("%s: %s", __func__,
330		    evutil_socket_error_to_string(EVUTIL_SOCKET_ERROR())));
331		return res;
332	}
333
334	if (win32op->readset_out->fd_count) {
335		i = evutil_weakrand_range_(&base->weakrand_seed,
336		    win32op->readset_out->fd_count);
337		for (j=0; j<win32op->readset_out->fd_count; ++j) {
338			if (++i >= win32op->readset_out->fd_count)
339				i = 0;
340			s = win32op->readset_out->fd_array[i];
341			evmap_io_active_(base, s, EV_READ);
342		}
343	}
344	if (win32op->exset_out->fd_count) {
345		i = evutil_weakrand_range_(&base->weakrand_seed,
346		    win32op->exset_out->fd_count);
347		for (j=0; j<win32op->exset_out->fd_count; ++j) {
348			if (++i >= win32op->exset_out->fd_count)
349				i = 0;
350			s = win32op->exset_out->fd_array[i];
351			evmap_io_active_(base, s, EV_WRITE);
352		}
353	}
354	if (win32op->writeset_out->fd_count) {
355		i = evutil_weakrand_range_(&base->weakrand_seed,
356		    win32op->writeset_out->fd_count);
357		for (j=0; j<win32op->writeset_out->fd_count; ++j) {
358			if (++i >= win32op->writeset_out->fd_count)
359				i = 0;
360			s = win32op->writeset_out->fd_array[i];
361			evmap_io_active_(base, s, EV_WRITE);
362		}
363	}
364	return (0);
365}
366
367void
368win32_dealloc(struct event_base *base)
369{
370	struct win32op *win32op = base->evbase;
371
372	evsig_dealloc_(base);
373	if (win32op->readset_in)
374		mm_free(win32op->readset_in);
375	if (win32op->writeset_in)
376		mm_free(win32op->writeset_in);
377	if (win32op->readset_out)
378		mm_free(win32op->readset_out);
379	if (win32op->writeset_out)
380		mm_free(win32op->writeset_out);
381	if (win32op->exset_out)
382		mm_free(win32op->exset_out);
383	/* XXXXX free the tree. */
384
385	memset(win32op, 0, sizeof(*win32op));
386	mm_free(win32op);
387}
388
389#endif
390