xref: /PHP-7.0/win32/select.c (revision 76c9b584)
1 /*
2   +----------------------------------------------------------------------+
3   | PHP Version 7                                                        |
4   +----------------------------------------------------------------------+
5   | Copyright (c) 1997-2017 The PHP Group                                |
6   +----------------------------------------------------------------------+
7   | This source file is subject to version 3.01 of the PHP license,      |
8   | that is bundled with this package in the file LICENSE, and is        |
9   | available through the world-wide-web at the following url:           |
10   | http://www.php.net/license/3_01.txt                                  |
11   | If you did not receive a copy of the PHP license and are unable to   |
12   | obtain it through the world-wide-web, please send a note to          |
13   | license@php.net so we can mail you a copy immediately.               |
14   +----------------------------------------------------------------------+
15   | Author: Wez Furlong <wez@thebrainroom.com>                           |
16   +----------------------------------------------------------------------+
17 */
18 
19 #include "php.h"
20 #include "php_network.h"
21 
22 #ifdef PHP_WIN32
23 
24 /* $Id$ */
25 
26 /* Win32 select() will only work with sockets, so we roll our own implementation here.
27  * - If you supply only sockets, this simply passes through to winsock select().
28  * - If you supply file handles, there is no way to distinguish between
29  *   ready for read/write or OOB, so any set in which the handle is found will
30  *   be marked as ready.
31  * - If you supply a mixture of handles and sockets, the system will interleave
32  *   calls between select() and WaitForMultipleObjects(). The time slicing may
33  *   cause this function call to take up to 100 ms longer than you specified.
34  * - Calling this with NULL sets as a portable way to sleep with sub-second
35  *   accuracy is not supported.
36  * */
php_select(int max_fd,fd_set * rfds,fd_set * wfds,fd_set * efds,struct timeval * tv)37 PHPAPI int php_select(int max_fd, fd_set *rfds, fd_set *wfds, fd_set *efds, struct timeval *tv)
38 {
39 	ULONGLONG ms_total, limit;
40 	HANDLE handles[MAXIMUM_WAIT_OBJECTS];
41 	int handle_slot_to_fd[MAXIMUM_WAIT_OBJECTS];
42 	int n_handles = 0, i;
43 	fd_set sock_read, sock_write, sock_except;
44 	fd_set aread, awrite, aexcept;
45 	int sock_max_fd = -1;
46 	struct timeval tvslice;
47 	int retcode;
48 
49 #define SAFE_FD_ISSET(fd, set)	(set != NULL && FD_ISSET(fd, set))
50 
51 	/* calculate how long we need to wait in milliseconds */
52 	if (tv == NULL) {
53 		ms_total = INFINITE;
54 	} else {
55 		ms_total = tv->tv_sec * 1000;
56 		ms_total += tv->tv_usec / 1000;
57 	}
58 
59 	FD_ZERO(&sock_read);
60 	FD_ZERO(&sock_write);
61 	FD_ZERO(&sock_except);
62 
63 	/* build an array of handles for non-sockets */
64 	for (i = 0; i < max_fd; i++) {
65 		if (SAFE_FD_ISSET(i, rfds) || SAFE_FD_ISSET(i, wfds) || SAFE_FD_ISSET(i, efds)) {
66 			handles[n_handles] = (HANDLE)(zend_uintptr_t)_get_osfhandle(i);
67 			if (handles[n_handles] == INVALID_HANDLE_VALUE) {
68 				/* socket */
69 				if (SAFE_FD_ISSET(i, rfds)) {
70 					FD_SET((uint32_t)i, &sock_read);
71 				}
72 				if (SAFE_FD_ISSET(i, wfds)) {
73 					FD_SET((uint32_t)i, &sock_write);
74 				}
75 				if (SAFE_FD_ISSET(i, efds)) {
76 					FD_SET((uint32_t)i, &sock_except);
77 				}
78 				if (i > sock_max_fd) {
79 					sock_max_fd = i;
80 				}
81 			} else {
82 				handle_slot_to_fd[n_handles] = i;
83 				n_handles++;
84 			}
85 		}
86 	}
87 
88 	if (n_handles == 0) {
89 		/* plain sockets only - let winsock handle the whole thing */
90 		return select(max_fd, rfds, wfds, efds, tv);
91 	}
92 
93 	/* mixture of handles and sockets; lets multiplex between
94 	 * winsock and waiting on the handles */
95 
96 	FD_ZERO(&aread);
97 	FD_ZERO(&awrite);
98 	FD_ZERO(&aexcept);
99 
100 	limit = GetTickCount64() + ms_total;
101 	do {
102 		retcode = 0;
103 
104 		if (sock_max_fd >= 0) {
105 			/* overwrite the zero'd sets here; the select call
106 			 * will clear those that are not active */
107 			aread = sock_read;
108 			awrite = sock_write;
109 			aexcept = sock_except;
110 
111 			tvslice.tv_sec = 0;
112 			tvslice.tv_usec = 100000;
113 
114 			retcode = select(sock_max_fd+1, &aread, &awrite, &aexcept, &tvslice);
115 		}
116 		if (n_handles > 0) {
117 			/* check handles */
118 			DWORD wret;
119 
120 			wret = WaitForMultipleObjects(n_handles, handles, FALSE, retcode > 0 ? 0 : 100);
121 
122 			if (wret == WAIT_TIMEOUT) {
123 				/* set retcode to 0; this is the default.
124 				 * select() may have set it to something else,
125 				 * in which case we leave it alone, so this branch
126 				 * does nothing */
127 				;
128 			} else if (wret == WAIT_FAILED) {
129 				if (retcode == 0) {
130 					retcode = -1;
131 				}
132 			} else {
133 				if (retcode < 0) {
134 					retcode = 0;
135 				}
136 				for (i = 0; i < n_handles; i++) {
137 					if (WAIT_OBJECT_0 == WaitForSingleObject(handles[i], 0)) {
138 						if (SAFE_FD_ISSET(handle_slot_to_fd[i], rfds)) {
139 							FD_SET((uint32_t)handle_slot_to_fd[i], &aread);
140 						}
141 						if (SAFE_FD_ISSET(handle_slot_to_fd[i], wfds)) {
142 							FD_SET((uint32_t)handle_slot_to_fd[i], &awrite);
143 						}
144 						if (SAFE_FD_ISSET(handle_slot_to_fd[i], efds)) {
145 							FD_SET((uint32_t)handle_slot_to_fd[i], &aexcept);
146 						}
147 						retcode++;
148 					}
149 				}
150 			}
151 		}
152 	} while (retcode == 0 && (ms_total == INFINITE || GetTickCount64() < limit));
153 
154 	if (rfds) {
155 		*rfds = aread;
156 	}
157 	if (wfds) {
158 		*wfds = awrite;
159 	}
160 	if (efds) {
161 		*efds = aexcept;
162 	}
163 
164 	return retcode;
165 }
166 
167 #endif
168 
169 /*
170  * Local variables:
171  * tab-width: 4
172  * c-basic-offset: 4
173  * End:
174  * vim600: noet sw=4 ts=4 fdm=marker
175  * vim<600: noet sw=4 ts=4
176  */
177