1 /* 2 * Copyright (c) 2013 - Andre Roth <neolynx@gmail.com> 3 * 4 * This program is free software; you can redistribute it and/or modify 5 * it under the terms of the GNU Lesser General Public License as published by 6 * the Free Software Foundation version 2.1 of the License. 7 * 8 * This program is distributed in the hope that it will be useful, 9 * but WITHOUT ANY WARRANTY; without even the implied warranty of 10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 11 * GNU Lesser General Public License for more details. 12 * 13 * You should have received a copy of the GNU Lesser General Public License 14 * along with this program; if not, write to the Free Software 15 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 16 * Or, point your browser to http://www.gnu.org/licenses/old-licenses/gpl-2.0.html 17 * 18 */ 19 20 /** 21 * @file atsc_eit.h 22 * @ingroup dvb_table 23 * @brief Provides the table parser for the ATSC EIT (Event Information Table) 24 * @copyright GNU Lesser General Public License version 2.1 (LGPLv2.1) 25 * @author Mauro Carvalho Chehab 26 * @author Andre Roth 27 * 28 * @par Relevant specs 29 * The table described herein is defined at: 30 * - ATSC A/65:2009 31 * 32 * @see 33 * http://www.etherguidesystems.com/help/sdos/atsc/syntax/tablesections/eitks.aspx 34 * 35 * @par Bug Report 36 * Please submit bug reports and patches to linux-media@vger.kernel.org 37 */ 38 39 #ifndef _ATSC_EIT_H 40 #define _ATSC_EIT_H 41 42 #include <stdint.h> 43 #include <unistd.h> /* ssize_t */ 44 #include <time.h> 45 46 #include <libdvbv5/atsc_header.h> 47 48 /** 49 * @def ATSC_TABLE_EIT 50 * @brief ATSC EIT table ID 51 * @ingroup dvb_table 52 */ 53 #define ATSC_TABLE_EIT 0xCB 54 55 /** 56 * @struct atsc_table_eit_event 57 * @brief ATSC EIT event table 58 * @ingroup dvb_table 59 * 60 * @param event_id an uniquelly (inside a service ID) event ID 61 * @param title_length title length. Zero means no title 62 * @param duration duration in seconds 63 * @param etm Extended Text Message location 64 * @param descriptor pointer to struct dvb_desc 65 * @param next pointer to struct atsc_table_eit_event 66 * @param start event start (in struct tm format) 67 * @param source_id source id (obtained from ATSC header) 68 * 69 * This structure is used to store the original ATSC EIT event table, 70 * converting the integer fields to the CPU endianness, and converting the 71 * timestamps to a way that it is better handled on Linux. 72 * 73 * The undocumented parameters are used only internally by the API and/or 74 * are fields that are reserved. They shouldn't be used, as they may change 75 * on future API releases. 76 * 77 * Everything after atsc_table_eit_event::descriptor (including it) won't 78 * be bit-mapped to the data parsed from the MPEG TS. So, metadata are added 79 * there. 80 */ 81 struct atsc_table_eit_event { 82 union { 83 uint16_t bitfield; 84 struct { 85 uint16_t event_id:14; 86 uint16_t one:2; 87 } __attribute__((packed)); 88 } __attribute__((packed)); 89 uint32_t start_time; 90 union { 91 uint32_t bitfield2; 92 struct { 93 uint32_t title_length:8; 94 uint32_t duration:20; 95 uint32_t etm:2; 96 uint32_t one2:2; 97 uint32_t :2; 98 } __attribute__((packed)); 99 } __attribute__((packed)); 100 struct dvb_desc *descriptor; 101 struct atsc_table_eit_event *next; 102 struct tm start; 103 uint16_t source_id; 104 } __attribute__((packed)); 105 106 /** 107 * @union atsc_table_eit_desc_length 108 * @brief ATSC EIT descriptor length 109 * @ingroup dvb_table 110 * 111 * @param desc_length descriptor length 112 * 113 * This structure is used to store the original ATSC EIT event table, 114 * converting the integer fields to the CPU endianness, and converting the 115 * timestamps to a way that it is better handled on Linux. 116 * 117 * The undocumented parameters are used only internally by the API and/or 118 * are fields that are reserved. They shouldn't be used, as they may change 119 * on future API releases. 120 */ 121 union atsc_table_eit_desc_length { 122 uint16_t bitfield; 123 struct { 124 uint16_t desc_length:12; 125 uint16_t reserved:4; 126 } __attribute__((packed)); 127 } __attribute__((packed)); 128 129 /** 130 * @struct atsc_table_eit 131 * @brief ATSC EIT table 132 * @ingroup dvb_table 133 * 134 * @param header struct dvb_table_header content 135 * @param protocol_version protocol version 136 * @param events events 137 * @param event pointer to struct atsc_table_eit_event 138 * 139 * This structure is used to store the original ATSC EIT table, 140 * converting the integer fields to the CPU endianness. 141 * 142 * Everything after atsc_table_eit::event (including it) won't 143 * be bit-mapped to the data parsed from the MPEG TS. So, metadata are added 144 * there. 145 */ 146 struct atsc_table_eit { 147 struct dvb_table_header header; 148 uint8_t protocol_version; 149 uint8_t events; 150 struct atsc_table_eit_event *event; 151 } __attribute__((packed)); 152 153 /** 154 * @brief Macro used to find event on an ATSC EIT table 155 * @ingroup dvb_table 156 * 157 * @param _event event to seek 158 * @param _eit pointer to struct atsc_table_eit_event 159 */ 160 #define atsc_eit_event_foreach(_event, _eit) \ 161 if (_eit && _eit->event) \ 162 for( struct atsc_table_eit_event *_event = _eit->event; _event; _event = _event->next ) \ 163 164 struct dvb_v5_fe_parms; 165 166 #ifdef __cplusplus 167 extern "C" { 168 #endif 169 170 /** 171 * @brief Initializes and parses ATSC EIT table 172 * @ingroup dvb_table 173 * 174 * @param parms struct dvb_v5_fe_parms pointer to the opened device 175 * @param buf buffer containing the EIT raw data 176 * @param buflen length of the buffer 177 * @param table pointer to struct atsc_table_eit to be allocated and filled 178 * 179 * This function allocates an ATSC EIT table and fills the fields inside 180 * the struct. It also makes sure that all fields will follow the CPU 181 * endianness. Due to that, the content of the buffer may change. 182 * 183 * @return On success, it returns the size of the allocated struct. 184 * A negative value indicates an error. 185 */ 186 ssize_t atsc_table_eit_init(struct dvb_v5_fe_parms *parms, const uint8_t *buf, 187 ssize_t buflen, struct atsc_table_eit **table); 188 189 /** 190 * @brief Frees all data allocated by the ATSC EIT table parser 191 * @ingroup dvb_table 192 * 193 * @param table pointer to struct atsc_table_eit to be freed 194 */ 195 void atsc_table_eit_free(struct atsc_table_eit *table); 196 197 /** 198 * @brief Prints the content of the ATSC EIT table 199 * @ingroup dvb_table 200 * 201 * @param parms struct dvb_v5_fe_parms pointer to the opened device 202 * @param table pointer to struct atsc_table_eit 203 */ 204 void atsc_table_eit_print(struct dvb_v5_fe_parms *parms, 205 struct atsc_table_eit *table); 206 207 /** 208 * @brief Converts an ATSC EIT formatted timestamp into struct tm 209 * @ingroup ancillary 210 * 211 * @param start_time event on ATSC EIT time format 212 * @param tm pointer to struct tm where the converted timestamp will 213 * be stored. 214 */ 215 void atsc_time(const uint32_t start_time, struct tm *tm); 216 217 #ifdef __cplusplus 218 } 219 #endif 220 221 #endif 222