xref: /PHP-7.2/sapi/fpm/fpm/events/select.c (revision 7a7ec01a)
1 /*
2    +----------------------------------------------------------------------+
3    | PHP Version 7                                                        |
4    +----------------------------------------------------------------------+
5    | Copyright (c) 1997-2018 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    | Authors: Jerome Loyet <jerome@loyet.net>                             |
16    +----------------------------------------------------------------------+
17 */
18 
19 /* $Id$ */
20 
21 #include "../fpm_config.h"
22 #include "../fpm_events.h"
23 #include "../fpm.h"
24 #include "../zlog.h"
25 
26 #if HAVE_SELECT
27 
28 /* According to POSIX.1-2001 */
29 #include <sys/select.h>
30 
31 /* According to earlier standards */
32 #include <sys/time.h>
33 #include <sys/types.h>
34 #include <unistd.h>
35 
36 #include <errno.h>
37 
38 static int fpm_event_select_init(int max);
39 static int fpm_event_select_wait(struct fpm_event_queue_s *queue, unsigned long int timeout);
40 static int fpm_event_select_add(struct fpm_event_s *ev);
41 static int fpm_event_select_remove(struct fpm_event_s *ev);
42 
43 static struct fpm_event_module_s select_module = {
44 	.name = "select",
45 	.support_edge_trigger = 0,
46 	.init = fpm_event_select_init,
47 	.clean = NULL,
48 	.wait = fpm_event_select_wait,
49 	.add = fpm_event_select_add,
50 	.remove = fpm_event_select_remove,
51 };
52 
53 static fd_set fds;
54 
55 #endif /* HAVE_SELECT */
56 
57 /*
58  * return the module configuration
59  */
fpm_event_select_module()60 struct fpm_event_module_s *fpm_event_select_module() /* {{{ */
61 {
62 #if HAVE_SELECT
63 	return &select_module;
64 #else
65 	return NULL;
66 #endif /* HAVE_SELECT */
67 }
68 /* }}} */
69 
70 #if HAVE_SELECT
71 
72 /*
73  * Init the module
74  */
fpm_event_select_init(int max)75 static int fpm_event_select_init(int max) /* {{{ */
76 {
77 	FD_ZERO(&fds);
78 	return 0;
79 }
80 /* }}} */
81 
82 
83 /*
84  * wait for events or timeout
85  */
fpm_event_select_wait(struct fpm_event_queue_s * queue,unsigned long int timeout)86 static int fpm_event_select_wait(struct fpm_event_queue_s *queue, unsigned long int timeout) /* {{{ */
87 {
88 	int ret;
89 	struct fpm_event_queue_s *q;
90 	fd_set current_fds;
91 	struct timeval t;
92 
93 	/* copy fds because select() alters it */
94 	current_fds = fds;
95 
96 	/* fill struct timeval with timeout */
97 	t.tv_sec = timeout / 1000;
98 	t.tv_usec = (timeout % 1000) * 1000;
99 
100 	/* wait for inconming event or timeout */
101 	ret = select(FD_SETSIZE, &current_fds, NULL, NULL, &t);
102 	if (ret == -1) {
103 
104 		/* trigger error unless signal interrupt */
105 		if (errno != EINTR) {
106 			zlog(ZLOG_WARNING, "poll() returns %d", errno);
107 			return -1;
108 		}
109 	}
110 
111 	/* events have been triggered */
112 	if (ret > 0) {
113 
114 		/* trigger POLLIN events */
115 		q = queue;
116 		while (q) {
117 			if (q->ev) { /* sanity check */
118 
119 				/* check if the event has been triggered */
120 				if (FD_ISSET(q->ev->fd, &current_fds)) {
121 
122 					/* fire the event */
123 					fpm_event_fire(q->ev);
124 
125 					/* sanity check */
126 					if (fpm_globals.parent_pid != getpid()) {
127 						return -2;
128 					}
129 				}
130 			}
131 			q = q->next; /* iterate */
132 		}
133 	}
134 	return ret;
135 
136 }
137 /* }}} */
138 
139 /*
140  * Add a FD to the fd set
141  */
fpm_event_select_add(struct fpm_event_s * ev)142 static int fpm_event_select_add(struct fpm_event_s *ev) /* {{{ */
143 {
144 	/* check size limitation */
145 	if (ev->fd >= FD_SETSIZE) {
146 		zlog(ZLOG_ERROR, "select: not enough space in the select fd list (max = %d). Please consider using another event mechanism.", FD_SETSIZE);
147 		return -1;
148 	}
149 
150 	/* add the FD if not already in */
151 	if (!FD_ISSET(ev->fd, &fds)) {
152 		FD_SET(ev->fd, &fds);
153 		ev->index = ev->fd;
154 	}
155 
156 	return 0;
157 }
158 /* }}} */
159 
160 /*
161  * Remove a FD from the fd set
162  */
fpm_event_select_remove(struct fpm_event_s * ev)163 static int fpm_event_select_remove(struct fpm_event_s *ev) /* {{{ */
164 {
165 	/* remove the fd if it's in */
166 	if (FD_ISSET(ev->fd, &fds)) {
167 		FD_CLR(ev->fd, &fds);
168 		ev->index = -1;
169 	}
170 
171 	return 0;
172 }
173 /* }}} */
174 
175 #endif /* HAVE_SELECT */
176