Tristan Matthews | 0a329cc | 2013-07-17 13:20:14 -0400 | [diff] [blame] | 1 | /* $Id$ */ |
| 2 | /* |
| 3 | * Copyright (C) 2008-2011 Teluu Inc. (http://www.teluu.com) |
| 4 | * Copyright (C) 2003-2008 Benny Prijono <benny@prijono.org> |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or modify |
| 7 | * it under the terms of the GNU General Public License as published by |
| 8 | * the Free Software Foundation; either version 2 of the License, or |
| 9 | * (at your option) any later version. |
| 10 | * |
| 11 | * This program is distributed in the hope that it will be useful, |
| 12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 14 | * GNU General Public License for more details. |
| 15 | * |
| 16 | * You should have received a copy of the GNU General Public License |
| 17 | * along with this program; if not, write to the Free Software |
| 18 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| 19 | */ |
| 20 | #ifndef __PJ_SELECT_H__ |
| 21 | #define __PJ_SELECT_H__ |
| 22 | |
| 23 | /** |
| 24 | * @file sock_select.h |
| 25 | * @brief Socket select(). |
| 26 | */ |
| 27 | |
| 28 | #include <pj/types.h> |
| 29 | |
| 30 | PJ_BEGIN_DECL |
| 31 | |
| 32 | /** |
| 33 | * @defgroup PJ_SOCK_SELECT Socket select() API. |
| 34 | * @ingroup PJ_IO |
| 35 | * @{ |
| 36 | * This module provides portable abstraction for \a select() like API. |
| 37 | * The abstraction is needed so that it can utilize various event |
| 38 | * dispatching mechanisms that are available across platforms. |
| 39 | * |
| 40 | * The API is very similar to normal \a select() usage. |
| 41 | * |
| 42 | * \section pj_sock_select_examples_sec Examples |
| 43 | * |
| 44 | * For some examples on how to use the select API, please see: |
| 45 | * |
| 46 | * - \ref page_pjlib_select_test |
| 47 | */ |
| 48 | |
| 49 | /** |
| 50 | * Portable structure declarations for pj_fd_set. |
| 51 | * The implementation of pj_sock_select() does not use this structure |
| 52 | * per-se, but instead it will use the native fd_set structure. However, |
| 53 | * we must make sure that the size of pj_fd_set_t can accomodate the |
| 54 | * native fd_set structure. |
| 55 | */ |
| 56 | typedef struct pj_fd_set_t |
| 57 | { |
| 58 | pj_sock_t data[PJ_IOQUEUE_MAX_HANDLES+ 4]; /**< Opaque buffer for fd_set */ |
| 59 | } pj_fd_set_t; |
| 60 | |
| 61 | |
| 62 | /** |
| 63 | * Initialize the descriptor set pointed to by fdsetp to the null set. |
| 64 | * |
| 65 | * @param fdsetp The descriptor set. |
| 66 | */ |
| 67 | PJ_DECL(void) PJ_FD_ZERO(pj_fd_set_t *fdsetp); |
| 68 | |
| 69 | |
| 70 | /** |
| 71 | * This is an internal function, application shouldn't use this. |
| 72 | * |
| 73 | * Get the number of descriptors in the set. This is defined in sock_select.c |
| 74 | * This function will only return the number of sockets set from PJ_FD_SET |
| 75 | * operation. When the set is modified by other means (such as by select()), |
| 76 | * the count will not be reflected here. |
| 77 | * |
| 78 | * @param fdsetp The descriptor set. |
| 79 | * |
| 80 | * @return Number of descriptors in the set. |
| 81 | */ |
| 82 | PJ_DECL(pj_size_t) PJ_FD_COUNT(const pj_fd_set_t *fdsetp); |
| 83 | |
| 84 | |
| 85 | /** |
| 86 | * Add the file descriptor fd to the set pointed to by fdsetp. |
| 87 | * If the file descriptor fd is already in this set, there shall be no effect |
| 88 | * on the set, nor will an error be returned. |
| 89 | * |
| 90 | * @param fd The socket descriptor. |
| 91 | * @param fdsetp The descriptor set. |
| 92 | */ |
| 93 | PJ_DECL(void) PJ_FD_SET(pj_sock_t fd, pj_fd_set_t *fdsetp); |
| 94 | |
| 95 | /** |
| 96 | * Remove the file descriptor fd from the set pointed to by fdsetp. |
| 97 | * If fd is not a member of this set, there shall be no effect on the set, |
| 98 | * nor will an error be returned. |
| 99 | * |
| 100 | * @param fd The socket descriptor. |
| 101 | * @param fdsetp The descriptor set. |
| 102 | */ |
| 103 | PJ_DECL(void) PJ_FD_CLR(pj_sock_t fd, pj_fd_set_t *fdsetp); |
| 104 | |
| 105 | |
| 106 | /** |
| 107 | * Evaluate to non-zero if the file descriptor fd is a member of the set |
| 108 | * pointed to by fdsetp, and shall evaluate to zero otherwise. |
| 109 | * |
| 110 | * @param fd The socket descriptor. |
| 111 | * @param fdsetp The descriptor set. |
| 112 | * |
| 113 | * @return Nonzero if fd is member of the descriptor set. |
| 114 | */ |
| 115 | PJ_DECL(pj_bool_t) PJ_FD_ISSET(pj_sock_t fd, const pj_fd_set_t *fdsetp); |
| 116 | |
| 117 | |
| 118 | /** |
| 119 | * This function wait for a number of file descriptors to change status. |
| 120 | * The behaviour is the same as select() function call which appear in |
| 121 | * standard BSD socket libraries. |
| 122 | * |
| 123 | * @param n On Unices, this specifies the highest-numbered |
| 124 | * descriptor in any of the three set, plus 1. On Windows, |
| 125 | * the value is ignored. |
| 126 | * @param readfds Optional pointer to a set of sockets to be checked for |
| 127 | * readability. |
| 128 | * @param writefds Optional pointer to a set of sockets to be checked for |
| 129 | * writability. |
| 130 | * @param exceptfds Optional pointer to a set of sockets to be checked for |
| 131 | * errors. |
| 132 | * @param timeout Maximum time for select to wait, or null for blocking |
| 133 | * operations. |
| 134 | * |
| 135 | * @return The total number of socket handles that are ready, or |
| 136 | * zero if the time limit expired, or -1 if an error occurred. |
| 137 | */ |
| 138 | PJ_DECL(int) pj_sock_select( int n, |
| 139 | pj_fd_set_t *readfds, |
| 140 | pj_fd_set_t *writefds, |
| 141 | pj_fd_set_t *exceptfds, |
| 142 | const pj_time_val *timeout); |
| 143 | |
| 144 | |
| 145 | /** |
| 146 | * @} |
| 147 | */ |
| 148 | |
| 149 | |
| 150 | PJ_END_DECL |
| 151 | |
| 152 | #endif /* __PJ_SELECT_H__ */ |