Asterisk - The Open Source Telephony Project  GIT-master-b7027de
poll-compat.h
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1 /*
2  * Asterisk -- An open source telephony toolkit.
3  *
4  * See http://www.asterisk.org for more information about
5  * the Asterisk project. Please do not directly contact
6  * any of the maintainers of this project for assistance;
7  * the project provides a web site, mailing lists and IRC
8  * channels for your use.
9  */
10 
11 /*---------------------------------------------------------------------------*\
12  $Id$
13 
14  NAME
15 
16  poll - select(2)-based poll() emulation function for BSD systems.
17 
18  SYNOPSIS
19  #include "poll.h"
20 
21  struct pollfd
22  {
23  int fd;
24  short events;
25  short revents;
26  }
27 
28  int poll (struct pollfd *pArray, unsigned long n_fds, int timeout)
29 
30  DESCRIPTION
31 
32  This file, and the accompanying "poll.c", implement the System V
33  poll(2) system call for BSD systems (which typically do not provide
34  poll()). Poll() provides a method for multiplexing input and output
35  on multiple open file descriptors; in traditional BSD systems, that
36  capability is provided by select(). While the semantics of select()
37  differ from those of poll(), poll() can be readily emulated in terms
38  of select() -- which is how this function is implemented.
39 
40  REFERENCES
41  Stevens, W. Richard. Unix Network Programming. Prentice-Hall, 1990.
42 
43  NOTES
44  1. This software requires an ANSI C compiler.
45 
46  LICENSE
47 
48  This software is released under the following license:
49 
50  Copyright (c) 1995-2002 Brian M. Clapper
51  All rights reserved.
52 
53  Redistribution and use in source and binary forms are
54  permitted provided that: (1) source distributions retain
55  this entire copyright notice and comment; (2) modifications
56  made to the software are prominently mentioned, and a copy
57  of the original software (or a pointer to its location) are
58  included; and (3) distributions including binaries display
59  the following acknowledgement: "This product includes
60  software developed by Brian M. Clapper <bmc@clapper.org>"
61  in the documentation or other materials provided with the
62  distribution. The name of the author may not be used to
63  endorse or promote products derived from this software
64  without specific prior written permission.
65 
66  THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS
67  OR IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE
68  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
69  PARTICULAR PURPOSE.
70 
71  Effectively, this means you can do what you want with the software
72  except remove this notice or take advantage of the author's name.
73  If you modify the software and redistribute your modified version,
74  you must indicate that your version is a modification of the
75  original, and you must provide either a pointer to or a copy of the
76  original.
77 \*---------------------------------------------------------------------------*/
78 
79 #ifndef __AST_POLL_COMPAT_H
80 #define __AST_POLL_COMPAT_H
81 
82 #include "asterisk/select.h"
83 
84 #ifndef AST_POLL_COMPAT
85 
86 #include <poll.h>
87 
88 #define ast_poll(a, b, c) poll(a, b, c)
89 
90 #else /* AST_POLL_COMPAT */
91 
92 #define POLLIN 0x01
93 #define POLLPRI 0x02
94 #define POLLOUT 0x04
95 #define POLLERR 0x08
96 #define POLLHUP 0x10
97 #define POLLNVAL 0x20
98 
99 struct pollfd {
100  int fd;
101  short events;
102  short revents;
103 };
104 
105 #ifdef __cplusplus
106 extern "C" {
107 #endif
108 
109 #define ast_poll(a, b, c) ast_internal_poll(a, b, c)
110 
111 int ast_internal_poll(struct pollfd *pArray, unsigned long n_fds, int timeout);
112 
113 #ifdef __cplusplus
114 }
115 #endif
116 
117 #endif /* AST_POLL_COMPAT */
118 
119 /*!
120  * \brief Same as poll(2), except the time is specified in microseconds and
121  * the tv argument is modified to indicate the time remaining.
122  */
123 int ast_poll2(struct pollfd *pArray, unsigned long n_fds, struct timeval *tv);
124 
125 /*!
126  * \brief Shortcut for conversion of FD_ISSET to poll(2)-based
127  */
128 static inline int ast_poll_fd_index(struct pollfd *haystack, int nfds, int needle)
129 {
130  int i;
131  for (i = 0; i < nfds; i++) {
132  if (haystack[i].fd == needle) {
133  return i;
134  }
135  }
136  return -1;
137 }
138 
139 #endif /* __AST_POLL_COMPAT_H */
static int timeout
Definition: cdr_mysql.c:86
static const struct adsi_event events[]
Definition: app_adsiprog.c:85
Bitfield expansions for ast_select.
static int ast_poll_fd_index(struct pollfd *haystack, int nfds, int needle)
Shortcut for conversion of FD_ISSET to poll(2)-based.
Definition: poll-compat.h:128
int ast_poll2(struct pollfd *pArray, unsigned long n_fds, struct timeval *tv)
Same as poll(2), except the time is specified in microseconds and the tv argument is modified to indi...
Definition: poll.c:268