Alexandre Lision | 8af73cb | 2013-12-10 14:11:20 -0500 | [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 __PJMEDIA_MASTER_PORT_H__ |
| 21 | #define __PJMEDIA_MASTER_PORT_H__ |
| 22 | |
| 23 | |
| 24 | /** |
| 25 | * @file master_port.h |
| 26 | * @brief Master port. |
| 27 | */ |
| 28 | #include <pjmedia/port.h> |
| 29 | |
| 30 | /** |
| 31 | * @defgroup PJMEDIA_MASTER_PORT Master Port |
| 32 | * @ingroup PJMEDIA_PORT_CLOCK |
| 33 | * @brief Thread based media clock provider |
| 34 | * @{ |
| 35 | * |
| 36 | * A master port has two media ports connected to it, and by convention |
| 37 | * thay are called downstream and upstream ports. The media stream flowing to |
| 38 | * the downstream port is called encoding or send direction, and media stream |
| 39 | * flowing to the upstream port is called decoding or receive direction |
| 40 | * (imagine the downstream as stream to remote endpoint, and upstream as |
| 41 | * local media port; media flowing to remote endpoint (downstream) will need |
| 42 | * to be encoded before it is transmitted to remote endpoint). |
| 43 | * |
| 44 | * A master port internally has an instance of @ref PJMEDIA_CLOCK, which |
| 45 | * provides the essensial timing for the master port. The @ref PJMEDIA_CLOCK |
| 46 | * runs asynchronously, and whenever a clock <b>tick</b> expires, a callback |
| 47 | * will be called, and the master port performs the following tasks: |
| 48 | * - it calls <b><tt>get_frame()</tt></b> from the downstream port, |
| 49 | * when give the frame to the upstream port by calling <b><tt>put_frame |
| 50 | * </tt></b> to the upstream port, and |
| 51 | * - performs the same task, but on the reverse direction (i.e. get the stream |
| 52 | * from upstream port and give it to the downstream port). |
| 53 | * |
| 54 | * Because master port enables media stream to flow automatically, it is |
| 55 | * said that the master port supplies @ref PJMEDIA_PORT_CLOCK to the |
| 56 | * media ports interconnection. |
| 57 | * |
| 58 | */ |
| 59 | |
| 60 | PJ_BEGIN_DECL |
| 61 | |
| 62 | |
| 63 | /** |
| 64 | * Opaque declaration for master port. |
| 65 | */ |
| 66 | typedef struct pjmedia_master_port pjmedia_master_port; |
| 67 | |
| 68 | |
| 69 | /** |
| 70 | * Create a master port. |
| 71 | * |
| 72 | * @param pool Pool to allocate master port from. |
| 73 | * @param u_port Upstream port. |
| 74 | * @param d_port Downstream port. |
| 75 | * @param options Options flags, from bitmask combinations from |
| 76 | * pjmedia_clock_options. |
| 77 | * @param p_m Pointer to receive the master port instance. |
| 78 | * |
| 79 | * @return PJ_SUCCESS on success. |
| 80 | */ |
| 81 | PJ_DECL(pj_status_t) pjmedia_master_port_create(pj_pool_t *pool, |
| 82 | pjmedia_port *u_port, |
| 83 | pjmedia_port *d_port, |
| 84 | unsigned options, |
| 85 | pjmedia_master_port **p_m); |
| 86 | |
| 87 | |
| 88 | /** |
| 89 | * Start the media flow. |
| 90 | * |
| 91 | * @param m The master port. |
| 92 | * |
| 93 | * @return PJ_SUCCESS on success. |
| 94 | */ |
| 95 | PJ_DECL(pj_status_t) pjmedia_master_port_start(pjmedia_master_port *m); |
| 96 | |
| 97 | |
| 98 | /** |
| 99 | * Stop the media flow. |
| 100 | * |
| 101 | * @param m The master port. |
| 102 | * |
| 103 | * @return PJ_SUCCESS on success. |
| 104 | */ |
| 105 | PJ_DECL(pj_status_t) pjmedia_master_port_stop(pjmedia_master_port *m); |
| 106 | |
| 107 | |
| 108 | /** |
| 109 | * Poll the master port clock and execute the callback when the clock tick has |
| 110 | * elapsed. This operation is only valid if the master port is created with |
| 111 | * #PJMEDIA_CLOCK_NO_ASYNC flag. |
| 112 | * |
| 113 | * @param m The master port. |
| 114 | * @param wait If non-zero, then the function will block until |
| 115 | * a clock tick elapsed and callback has been called. |
| 116 | * @param ts Optional argument to receive the current |
| 117 | * timestamp. |
| 118 | * |
| 119 | * @return Non-zero if clock tick has elapsed, or FALSE if |
| 120 | * the function returns before a clock tick has |
| 121 | * elapsed. |
| 122 | */ |
| 123 | PJ_DECL(pj_bool_t) pjmedia_master_port_wait(pjmedia_master_port *m, |
| 124 | pj_bool_t wait, |
| 125 | pj_timestamp *ts); |
| 126 | |
| 127 | |
| 128 | /** |
| 129 | * Change the upstream port. Note that application is responsible to destroy |
| 130 | * current upstream port (the one that is going to be replaced with the |
| 131 | * new port). |
| 132 | * |
| 133 | * @param m The master port. |
| 134 | * @param port Port to be used for upstream port. |
| 135 | * |
| 136 | * @return PJ_SUCCESS on success. |
| 137 | */ |
| 138 | PJ_DECL(pj_status_t) pjmedia_master_port_set_uport(pjmedia_master_port *m, |
| 139 | pjmedia_port *port); |
| 140 | |
| 141 | |
| 142 | /** |
| 143 | * Get the upstream port. |
| 144 | * |
| 145 | * @param m The master port. |
| 146 | * |
| 147 | * @return The upstream port. |
| 148 | */ |
| 149 | PJ_DECL(pjmedia_port*) pjmedia_master_port_get_uport(pjmedia_master_port*m); |
| 150 | |
| 151 | |
| 152 | /** |
| 153 | * Change the downstream port. Note that application is responsible to destroy |
| 154 | * current downstream port (the one that is going to be replaced with the |
| 155 | * new port). |
| 156 | * |
| 157 | * @param m The master port. |
| 158 | * @param port Port to be used for downstream port. |
| 159 | * |
| 160 | * @return PJ_SUCCESS on success. |
| 161 | */ |
| 162 | PJ_DECL(pj_status_t) pjmedia_master_port_set_dport(pjmedia_master_port *m, |
| 163 | pjmedia_port *port); |
| 164 | |
| 165 | |
| 166 | /** |
| 167 | * Get the downstream port. |
| 168 | * |
| 169 | * @param m The master port. |
| 170 | * |
| 171 | * @return The downstream port. |
| 172 | */ |
| 173 | PJ_DECL(pjmedia_port*) pjmedia_master_port_get_dport(pjmedia_master_port*m); |
| 174 | |
| 175 | |
| 176 | /** |
| 177 | * Destroy the master port, and optionally destroy the upstream and |
| 178 | * downstream ports. |
| 179 | * |
| 180 | * @param m The master port. |
| 181 | * @param destroy_ports If non-zero, the function will destroy both |
| 182 | * upstream and downstream ports too. |
| 183 | * |
| 184 | * @return PJ_SUCCESS on success. |
| 185 | */ |
| 186 | PJ_DECL(pj_status_t) pjmedia_master_port_destroy(pjmedia_master_port *m, |
| 187 | pj_bool_t destroy_ports); |
| 188 | |
| 189 | |
| 190 | |
| 191 | PJ_END_DECL |
| 192 | |
| 193 | /** |
| 194 | * @} |
| 195 | */ |
| 196 | |
| 197 | |
| 198 | #endif /* __PJMEDIA_MASTER_PORT_H__ */ |
| 199 | |