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/*
* Copyright (c) 2011-2014 - Mauro Carvalho Chehab
*
* 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 _LIBSCAN_H
#define _LIBSCAN_H
#include <stdint.h>
#include <linux/dvb/dmx.h>
#include <libdvbv5/descriptors.h>
#include <libdvbv5/dvb-sat.h>
/**
* @file dvb-scan.h
* @ingroup frontend_scan
* @brief Provides interfaces to scan programs inside MPEG-TS digital TV streams.
* @copyright GNU General Public License version 2 (GPLv2)
* @author Mauro Carvalho Chehab
*
* @par Bug Report
* Please submit bug reports and patches to linux-media@vger.kernel.org
*/
/* According with ISO/IEC 13818-1:2007 */
#define MAX_TABLE_SIZE 1024 * 1024
#ifdef __cplusplus
extern "C" {
#endif
struct dvb_entry;
/**
* @struct dvb_v5_descriptors_program
* @brief Associates PMT with PAT tables
* @ingroup frontend_scan
*
* @param pat_pgm pointer for PAT descriptor
* @param pmt pointer for PMT descriptor
*/
struct dvb_v5_descriptors_program {
struct dvb_table_pat_program *pat_pgm;
struct dvb_table_pmt *pmt;
};
/**
* @struct dvb_v5_descriptors
* @brief Contains the descriptors needed to scan the Service ID and other relevant info at a MPEG-TS Digital TV stream
* @ingroup frontend_scan
*
* @param delivery_system Delivery system of the parsed MPEG-TS
* @param entry struct dvb_entry pointer (see dvb-file.h)
* @param pat PAT table descriptor pointer
* @param vct VCT table descriptor pointer
* @param program PAT/PMT array associated programs found at MPEG-TS
* @param nit NIT table descriptor pointer
* @param sdt SDT table descriptor pointer
* @param num_program Number of program entries at program array.
*
* Those descriptors are filled by the scan routines when the tables are
* found. Otherwise, they're NULL.
*/
struct dvb_v5_descriptors {
uint32_t delivery_system;
struct dvb_entry *entry;
unsigned num_entry;
struct dvb_table_pat *pat;
struct atsc_table_vct *vct;
struct dvb_v5_descriptors_program *program;
struct dvb_table_nit *nit;
struct dvb_table_sdt *sdt;
unsigned num_program;
};
/**
* @struct dvb_table_filter
* @brief Describes the PES filters used by DVB scan
* @ingroup frontend_scan
*
* @param tid Table ID
* @param pid Program ID
* @param ts_id Table section ID (for multisession filtering). If no
* specific table section is needed, -1 should be used
* @param table pointer to a pointer for the table struct to be filled
* @param allow_section_gaps Allow non-continuous section numbering
* @param priv Internal structure used inside the DVB core. shouldn't
* be touched externally.
*/
struct dvb_table_filter {
/* Input data */
unsigned char tid;
uint16_t pid;
int ts_id;
void **table;
int allow_section_gaps;
/*
* Private temp data used by dvb_read_sections().
* Should not be filled outside dvb-scan.c, as they'll be
* overrided
*/
void *priv;
};
/**
* @brief deallocates all data associated with a table filter
* @ingroup frontend_scan
*
* @param sect table filter pointer
*/
void dvb_table_filter_free(struct dvb_table_filter *sect);
/**
* @brief read MPEG-TS tables that comes from a DTV card
* @ingroup frontend_scan
*
* @param parms pointer to struct dvb_v5_fe_parms created when the
* frontend is opened
* @param dmx_fd an opened demux file descriptor
* @param tid Table ID
* @param pid Program ID
* @param table pointer to a pointer for the table struct to be filled
* @param timeout Limit, in seconds, to read a MPEG-TS table
*
* This function is used to read the DVB tables by specifying a table ID and
* a program ID. The libdvbv5 should have a parser for the descriptors of the
* table type that should be parsed.
* The table will be automatically allocated on success.
* The function will read on the specified demux and return when reading is
* done or an error has occurred. If table is not NULL after the call, it has
* to be freed with the apropriate free table function (even if an error has
* occurred).
*
* If the application wants to abort the read operation, it can change the
* value of parms->p.abort to 1.
*
* Returns 0 on success or a negative error code.
*
* Example usage:
* @code
* struct dvb_table_pat *pat;
* int r = dvb_read_section( parms, dmx_fd, DVB_TABLE_PAT, DVB_TABLE_PAT_PID,
* (void **) &pat, 5 );
* if (r < 0)
* dvb_logerr("error reading PAT table");
* else {
* // do something with pat
* }
* if (pat)
* dvb_table_pat_free( pat );
* @endcode
*/
int dvb_read_section(struct dvb_v5_fe_parms *parms, int dmx_fd,
unsigned char tid, uint16_t pid, void **table,
unsigned timeout);
/**
* @brief read MPEG-TS tables that comes from a DTV card
* with an specific table section ID
* @ingroup frontend_scan
*
* @param parms pointer to struct dvb_v5_fe_parms created when the
* frontend is opened
* @param dmx_fd an opened demux file descriptor
* @param tid Table ID
* @param pid Program ID
* @param ts_id Table section ID (for multisession filtering). If no
* specific table section is needed, -1 should be used
* @param table pointer to a pointer for the table struct to be filled
* @param timeout limit, in seconds, to read a MPEG-TS table
*
* This is a variant of dvb_read_section() that also seeks for an specific
* table section ID given by ts_id.
*/
int dvb_read_section_with_id(struct dvb_v5_fe_parms *parms, int dmx_fd,
unsigned char tid, uint16_t pid, int ts_id,
void **table, unsigned timeout);
/**
* @brief read MPEG-TS tables that comes from a DTV card
* @ingroup frontend_scan
*
* @param parms pointer to struct dvb_v5_fe_parms created when the
* frontend is opened
* @param dmx_fd an opened demux file descriptor
* @param sect section filter pointer
* @param timeout limit, in seconds, to read a MPEG-TS table
*
* This is a variant of dvb_read_section() that uses a struct dvb_table_filter
* to specify the filter to use.
*/
int dvb_read_sections(struct dvb_v5_fe_parms *parms, int dmx_fd,
struct dvb_table_filter *sect,
unsigned timeout);
/**
* @brief allocates a struct dvb_v5_descriptors
* @ingroup frontend_scan
*
* @param delivery_system Delivery system to be used on the table
*
* At success, returns a pointer. NULL otherwise.
*/
struct dvb_v5_descriptors *dvb_scan_alloc_handler_table(uint32_t delivery_system);
/**
* @brief frees a struct dvb_v5_descriptors
* @ingroup frontend_scan
*
* @param dvb_scan_handler pointer to the struct to be freed.
*/
void dvb_scan_free_handler_table(struct dvb_v5_descriptors *dvb_scan_handler);
/**
* @brief Scans a DVB stream, looking for the tables needed to
* identify the programs inside a MPEG-TS
* @ingroup frontend_scan
*
* @param parms pointer to struct dvb_v5_fe_parms created when
* the frontend is opened
* @param dmx_fd an opened demux file descriptor
* @param delivery_system delivery system to be scanned
* @param other_nit use alternate table IDs for NIT and other tables
* @param timeout_multiply improves the timeout for each table reception
* by using a value that will multiply the wait
* time.
*
* Given an opened frontend and demux, this function seeks for all programs
* available at the transport stream, and parses the following tables:
* PAT, PMT, NIT, SDT (and VCT, if the delivery system is ATSC).
*
* On sucess, it returns a pointer to a struct dvb_v5_descriptors, that can
* either be used to tune into a service or to be stored inside a file.
*/
struct dvb_v5_descriptors *dvb_get_ts_tables(struct dvb_v5_fe_parms *parms, int dmx_fd,
uint32_t delivery_system,
unsigned other_nit,
unsigned timeout_multiply);
/**
* @brief frees a struct dvb_v5_descriptors
* @ingroup frontend_scan
*
* @param dvb_desc pointed to the structure to be freed.
*
* This function recursively frees everything that is allocated by
* dvb_get_ts_tables() and stored at dvb_desc, including dvb_desc itself.
*/
void dvb_free_ts_tables(struct dvb_v5_descriptors *dvb_desc);
/**
* @brief Callback for the application to show the frontend status
* @ingroup frontend_scan
*
* @param args a pointer, opaque to libdvbv5, to be used by the
* application if needed.
* @param parms pointer to struct dvb_v5_fe_parms created when the
* frontend is opened
*/
typedef int (check_frontend_t)(void *args, struct dvb_v5_fe_parms *parms);
/**
* @brief Scans a DVB dvb_add_scaned_transponder
* @ingroup frontend_scan
*
* @param parms pointer to struct dvb_v5_fe_parms created when the
* frontend is opened
* @param entry DVB file entry that corresponds to a transponder to be
* tuned
* @param dmx_fd an opened demux file descriptor
* @param check_frontend a pointer to a function that will show the frontend
* status while tuning into a transponder
* @param args a pointer, opaque to libdvbv5, that will be used when
* calling check_frontend. It should contain any parameters
* that could be needed by check_frontend.
* @param other_nit Use alternate table IDs for NIT and other tables
* @param timeout_multiply Improves the timeout for each table reception, by
*
* This is the function that applications should use when doing a transponders
* scan. It does everything needed to fill the entries with DVB programs
* (virtual channels) and detect the PIDs associated with them.
*
* A typical usage is to after open a channel file, open a dmx_fd and open
* a frontend. Then, seek for the MPEG tables on all the transponder
* frequencies with:
*
* @code
* for (entry = dvb_file->first_entry; entry != NULL; entry = entry->next) {
* struct dvb_v5_descriptors *dvb_scan_handler = NULL;
*
* dvb_scan_handler = dvb_scan_transponder(parms, entry, dmx_fd,
* &check_frontend, args,
* args->other_nit,
* args->timeout_multiply);
* if (parms->abort) {
* dvb_scan_free_handler_table(dvb_scan_handler);
* break;
* }
* if (dvb_scan_handler) {
* dvb_store_channel(&dvb_file_new, parms, dvb_scan_handler,
* args->get_detected, args->get_nit);
* dvb_scan_free_handler_table(dvb_scan_handler);
* }
* }
* @endcode
*/
struct dvb_v5_descriptors *dvb_scan_transponder(struct dvb_v5_fe_parms *parms,
struct dvb_entry *entry,
int dmx_fd,
check_frontend_t *check_frontend,
void *args,
unsigned other_nit,
unsigned timeout_multiply);
/**
* @brief Add new transponders to a dvb_file
* @ingroup frontend_scan
*
* @param parms pointer to struct dvb_v5_fe_parms created when the
* frontend is opened
* @param dvb_scan_handler pointer to a struct dvb_v5_descriptors containing
* scaned MPEG-TS
* @param first_entry first entry of a DVB file struct
* @param entry current entry on a DVB file struct
*
* When the NIT table is parsed, some new transponders could be described
* inside. This function adds new entries to a dvb_file struct, pointing
* to those new transponders. It is used inside the scan loop, as shown at
* the dvb_scan_transponder(), to add new channels.
*
* Example:
* @code
* for (entry = dvb_file->first_entry; entry != NULL; entry = entry->next) {
* struct dvb_v5_descriptors *dvb_scan_handler = NULL;
*
* dvb_scan_handler = dvb_scan_transponder(parms, entry, dmx_fd,
* &check_frontend, args,
* args->other_nit,
* args->timeout_multiply);
* if (parms->abort) {
* dvb_scan_free_handler_table(dvb_scan_handler);
* break;
* }
* if (dvb_scan_handler) {
* dvb_store_channel(&dvb_file_new, parms, dvb_scan_handler,
* args->get_detected, args->get_nit);
* dvb_scan_free_handler_table(dvb_scan_handler);
*
* dvb_add_scaned_transponders(parms, dvb_scan_handler,
* dvb_file->first_entry, entry);
*
* dvb_scan_free_handler_table(dvb_scan_handler);
* }
* }
* @endcode
*/
void dvb_add_scaned_transponders(struct dvb_v5_fe_parms *parms,
struct dvb_v5_descriptors *dvb_scan_handler,
struct dvb_entry *first_entry,
struct dvb_entry *entry);
#ifndef _DOXYGEN
/*
* Some ancillary functions used internally inside the library, used to
* identify duplicated transport streams and add new found transponder entries
*/
int dvb_estimate_freq_shift(struct dvb_v5_fe_parms *parms);
int dvb_new_freq_is_needed(struct dvb_entry *entry, struct dvb_entry *last_entry,
uint32_t freq, enum dvb_sat_polarization pol, int shift);
struct dvb_entry *dvb_scan_add_entry(struct dvb_v5_fe_parms *parms,
struct dvb_entry *first_entry,
struct dvb_entry *entry,
uint32_t freq, uint32_t shift,
enum dvb_sat_polarization pol);
int dvb_new_entry_is_needed(struct dvb_entry *entry,
struct dvb_entry *last_entry,
uint32_t freq, int shift,
enum dvb_sat_polarization pol, uint32_t stream_id);
struct dvb_entry *dvb_scan_add_entry_ex(struct dvb_v5_fe_parms *parms,
struct dvb_entry *first_entry,
struct dvb_entry *entry,
uint32_t freq, uint32_t shift,
enum dvb_sat_polarization pol,
uint32_t stream_id);
void dvb_update_transponders(struct dvb_v5_fe_parms *parms,
struct dvb_v5_descriptors *dvb_scan_handler,
struct dvb_entry *first_entry,
struct dvb_entry *entry);
#endif
#ifdef __cplusplus
}
#endif
#endif