/* * Copyright (c) 2011-2012 - Mauro Carvalho Chehab * Copyright (c) 2012 - Andre Roth * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation version 2 * of the License. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA * Or, point your browser to http://www.gnu.org/licenses/old-licenses/gpl-2.0.html * */ #ifndef _NIT_H #define _NIT_H #include #include /* ssize_t */ #include #include /** * @file nit.h * @ingroup dvb_table * @brief Provides the descriptors for NIT MPEG-TS table * @copyright GNU General Public License version 2 (GPLv2) * @author Mauro Carvalho Chehab * @author Andre Roth * * @par Bug Report * Please submit bug report and patches to linux-media@vger.kernel.org * * @par Relevant specs * The table described herein is defined at: * - ISO/IEC 13818-1 * - ETSI EN 300 468 * * @par Bug Report * Please submit bug reports and patches to linux-media@vger.kernel.org */ /** * @def DVB_TABLE_NIT * @brief NIT table ID * @ingroup dvb_table * @def DVB_TABLE_NIT2 * @brief NIT table ID (alternative table ID) * @ingroup dvb_table * @def DVB_TABLE_NIT_PID * @brief NIT Program ID * @ingroup dvb_table */ #define DVB_TABLE_NIT 0x40 #define DVB_TABLE_NIT2 0x41 #define DVB_TABLE_NIT_PID 0x10 /** * @union dvb_table_nit_transport_header * @brief MPEG-TS NIT transport header * @ingroup dvb_table * * @param transport_length transport length * * This structure is used to store the original NIT transport header, * converting the integer fields to the CPU endianness. * * The undocumented parameters are used only internally by the API and/or * are fields that are reserved. They shouldn't be used, as they may change * on future API releases. */ union dvb_table_nit_transport_header { uint16_t bitfield; struct { uint16_t transport_length:12; uint16_t reserved:4; } __attribute__((packed)); } __attribute__((packed)); /** * @struct dvb_table_nit_transport * @brief MPEG-TS NIT transport table * @ingroup dvb_table * * @param transport_id transport id * @param network_id network id * @param desc_length desc length * @param descriptor pointer to struct dvb_desc * @param next pointer to struct dvb_table_nit_transport * * This structure is used to store the original NIT transport table, * converting the integer fields to the CPU endianness. * * The undocumented parameters are used only internally by the API and/or * are fields that are reserved. They shouldn't be used, as they may change * on future API releases. * * Everything after dvb_table_nit_transport::descriptor (including it) won't * be bit-mapped to the data parsed from the MPEG TS. So, metadata are added * there. */ struct dvb_table_nit_transport { uint16_t transport_id; uint16_t network_id; union { uint16_t bitfield; struct { uint16_t desc_length:12; uint16_t reserved:4; } __attribute__((packed)); } __attribute__((packed)); struct dvb_desc *descriptor; struct dvb_table_nit_transport *next; } __attribute__((packed)); /** * @struct dvb_table_nit * @brief MPEG-TS NIT table * @ingroup dvb_table * * @param header struct dvb_table_header content * @param desc_length descriptor length * @param descriptor pointer to struct dvb_desc * @param transport pointer to struct dvb_table_nit_transport * * This structure is used to store the original NIT table, * converting the integer fields to the CPU endianness. * * The undocumented parameters are used only internally by the API and/or * are fields that are reserved. They shouldn't be used, as they may change * on future API releases. * * Everything after dvb_table_nit::descriptor (including it) won't be bit-mapped * to the data parsed from the MPEG TS. So, metadata are added there. */ struct dvb_table_nit { struct dvb_table_header header; union { uint16_t bitfield; struct { uint16_t desc_length:12; uint16_t reserved:4; } __attribute__((packed)); } __attribute__((packed)); struct dvb_desc *descriptor; struct dvb_table_nit_transport *transport; } __attribute__((packed)); /** * @brief typedef for a callback used when a NIT table entry is found * @ingroup dvb_table * * @param nit a struct dvb_table_nit pointer * @param desc a struct dvb_desc pointer * @param priv an opaque optional pointer */ typedef void nit_handler_callback_t(struct dvb_table_nit *nit, struct dvb_desc *desc, void *priv); /** * @brief typedef for a callback used when a NIT transport table entry is found * @ingroup dvb_table * * @param nit a struct dvb_table_nit pointer * @param tran a struct dvb_table_nit_transport pointer * @param desc a struct dvb_desc pointer * @param priv an opaque optional pointer */ typedef void nit_tran_handler_callback_t(struct dvb_table_nit *nit, struct dvb_table_nit_transport *tran, struct dvb_desc *desc, void *priv); /** * @brief Macro used to find a transport inside a NIT table * @ingroup dvb_table * * @param _tran transport to seek * @param _nit pointer to struct dvb_table_nit_transport */ #define dvb_nit_transport_foreach( _tran, _nit ) \ for (struct dvb_table_nit_transport *_tran = _nit->transport; _tran; _tran = _tran->next) \ struct dvb_v5_fe_parms; #ifdef __cplusplus extern "C" { #endif /** * @brief Initializes and parses NIT table * @ingroup dvb_table * * @param parms struct dvb_v5_fe_parms pointer to the opened device * @param buf buffer containing the NIT raw data * @param buflen length of the buffer * @param table pointer to struct dvb_table_nit to be allocated and filled * * This function allocates a NIT table and fills the fields inside * the struct. It also makes sure that all fields will follow the CPU * endianness. Due to that, the content of the buffer may change. * * @return On success, it returns the size of the allocated struct. * A negative value indicates an error. */ ssize_t dvb_table_nit_init (struct dvb_v5_fe_parms *parms, const uint8_t *buf, ssize_t buflen, struct dvb_table_nit **table); /** * @brief Frees all data allocated by the NIT table parser * @ingroup dvb_table * * @param table pointer to struct dvb_table_nit to be freed */ void dvb_table_nit_free(struct dvb_table_nit *table); /** * @brief Prints the content of the NIT table * @ingroup dvb_table * * @param parms struct dvb_v5_fe_parms pointer to the opened device * @param table pointer to struct dvb_table_nit */ void dvb_table_nit_print(struct dvb_v5_fe_parms *parms, struct dvb_table_nit *table); /** * @brief For each entry at NIT and NIT transport tables, call a callback * @ingroup dvb_table * * @param parms struct dvb_v5_fe_parms pointer to the opened device * @param table pointer to struct dvb_table_nit * @param descriptor indicates the NIT table descriptor to seek * @param call_nit a nit_handler_callback_t function to be called when a * new entry at the NIT table is found (or NULL). * @param call_tran a nit_tran_handler_callback_t function to be called * when a new entry at the NIT transport table is found * (or NULL). * @param priv an opaque pointer to be optionally used by the * callbacks. The function won't touch on it, just use * as an argument for the callback functions. * * When parsing a NIT entry, we need to call some code to properly handle * when a given descriptor in the table is found. This is used, for example, * to create newer transponders to seek during scan. * * For example, to seek for the CATV delivery system descriptor and call a * function that would add a new transponder to a scan procedure: * @code * dvb_table_nit_descriptor_handler( * &parms->p, dvb_scan_handler->nit, * cable_delivery_system_descriptor, * NULL, add_update_nit_dvbc, &tr); * @endcode */ void dvb_table_nit_descriptor_handler( struct dvb_v5_fe_parms *parms, struct dvb_table_nit *table, enum descriptors descriptor, nit_handler_callback_t *call_nit, nit_tran_handler_callback_t *call_tran, void *priv); #ifdef __cplusplus } #endif #endif