diff options
Diffstat (limited to 'lib/include/libdvbv5/descriptors.h')
| -rw-r--r-- | lib/include/libdvbv5/descriptors.h | 115 |
1 files changed, 109 insertions, 6 deletions
diff --git a/lib/include/libdvbv5/descriptors.h b/lib/include/libdvbv5/descriptors.h index 47738d85..fccbde27 100644 --- a/lib/include/libdvbv5/descriptors.h +++ b/lib/include/libdvbv5/descriptors.h @@ -18,8 +18,17 @@ * Or, point your browser to http://www.gnu.org/licenses/old-licenses/gpl-2.0.html */ -/* - * Descriptors, as defined on ETSI EN 300 468 V1.11.1 (2010-04) +/** + * @file descriptors.h + * @brief Provides a way to handle MPEG-TS descriptors found on Digital TV + * streams. + * @copyright GNU General Public License version 2 (GPLv2) + * @author Mauro Carvalho Chehab + * @author Andre Roth + * + * Most of the descriptors are defined on ETSI EN 300 468 V1.11.1 (2010-04) + * + * Please submit bug report and patches to linux-media@vger.kernel.org */ @@ -30,15 +39,24 @@ #include <stdint.h> #include <arpa/inet.h> +/** @brief Maximum size of a table session to be parsed */ #define DVB_MAX_PAYLOAD_PACKET_SIZE 4096 + +/** @brief number of bytes for the descriptor's CRC check */ #define DVB_CRC_SIZE 4 + +#ifndef _DOXYGEN struct dvb_v5_fe_parms; +#endif +/** @brief Function prototype for a function that initializes the descriptors parsing */ typedef void (*dvb_table_init_func)(struct dvb_v5_fe_parms *parms, const uint8_t *buf, ssize_t buflen, void **table); +/** @brief Table with all possible descriptors */ extern const dvb_table_init_func dvb_table_initializers[256]; +#ifndef _DOXYGEN #define bswap16(b) do {\ b = ntohs(b); \ } while (0) @@ -52,12 +70,26 @@ extern const dvb_table_init_func dvb_table_initializers[256]; uint8_t length; \ struct dvb_desc *next +#endif /* _DOXYGEN */ + +/** + * @struct dvb_desc + * @brief Linked list containing the several descriptors found on a + * MPEG-TS table + * + * @param type Descriptor type + * @param length Length of the descriptor + * @param next pointer to the next descriptor + * @param data Descriptor data + */ + struct dvb_desc { DVB_DESC_HEADER(); uint8_t data[]; } __attribute__((packed)); +#ifndef _DOXYGEN #define dvb_desc_foreach( _desc, _tbl ) \ for( struct dvb_desc *_desc = _tbl->descriptor; _desc; _desc = _desc->next ) \ @@ -66,28 +98,93 @@ struct dvb_desc { for( _struct *_desc = (_struct *) _tbl->descriptor; _desc; _desc = (_struct *) _desc->next ) \ if(_desc->type == _type) \ +#endif /* _DOXYGEN */ + #ifdef __cplusplus extern "C" { #endif +/** + * @brief Converts from BCD to CPU integer internal representation + * + * @param bcd value in BCD encoding + */ uint32_t dvb_bcd(uint32_t bcd); -void dvb_hexdump(struct dvb_v5_fe_parms *parms, const char *prefix, const unsigned char *buf, int len); +/** + * @brief dumps data into the logs in hexadecimal format + * + * @param parms Struct dvb_v5_fe_parms pointer + * @param prefix String to be printed before the dvb_hexdump + * @param buf Buffer to hex dump + * @param len Number of bytes to show + */ +void dvb_hexdump(struct dvb_v5_fe_parms *parms, const char *prefix, + const unsigned char *buf, int len); -int dvb_desc_parse(struct dvb_v5_fe_parms *parms, const uint8_t *buf, uint16_t section_length, struct dvb_desc **head_desc); +/** + * @brief parse MPEG-TS descriptors + * + * @param parms Struct dvb_v5_fe_parms pointer + * @param buf Buffer with data to be parsed + * @param buflen Size of the buffer to be parsed + * @param head_desc pointer to the place to store the parsed data + * + * This function takes a buf as argument and parses it to find the + * MPEG-TS descriptors inside it, creating a linked list. + * + * On success, head_desc will be allocated and filled with a linked list + * with the descriptors found inside the buffer. + * + * This function is used by the several MPEG-TS table handlers to parse + * the entire table that got read by dvb_read_sessions and other similar + * functions. + * + * @return Returns 0 on success, a negative value otherwise. + */ +int dvb_desc_parse(struct dvb_v5_fe_parms *parms, const uint8_t *buf, + uint16_t buflen, struct dvb_desc **head_desc); + +/** + * @brief frees a dvb_desc linked list + * + * @param list struct dvb_desc pointer. + */ void dvb_desc_free (struct dvb_desc **list); + +/** + * @brief prints the contents of a struct dvb_desc linked list + * + * @param parms Struct dvb_v5_fe_parms pointer + * @param desc struct dvb_desc pointer. + */ void dvb_desc_print(struct dvb_v5_fe_parms *parms, struct dvb_desc *desc); #ifdef __cplusplus } #endif -struct dvb_v5_fe_parms; - +/** @brief Function prototype for the descriptors parsing init code */ typedef int (*dvb_desc_init_func) (struct dvb_v5_fe_parms *parms, const uint8_t *buf, struct dvb_desc *desc); + +/** @brief Function prototype for the descriptors parsing print code */ typedef void (*dvb_desc_print_func)(struct dvb_v5_fe_parms *parms, const struct dvb_desc *desc); + +/** @brief Function prototype for the descriptors memory free code */ typedef void (*dvb_desc_free_func) (struct dvb_desc *desc); +/** + * @struct dvb_descriptor + * @brief Contains the parser information for the MPEG-TS parser code + * + * @param name String containing the name of the descriptor + * @param init Pointer to a function to initialize the descriptor + * parser. This function fills the descriptor-specific + * internal structures + * @param print Prints the content of the descriptor + * @param free Frees all memory blocks allocated by the init function + * @param size Descriptor's size, in bytes. + */ struct dvb_descriptor { const char *name; dvb_desc_init_func init; @@ -96,8 +193,14 @@ struct dvb_descriptor { ssize_t size; }; +/** + * @brief Contains the parsers for the several descriptors + */ extern const struct dvb_descriptor dvb_descriptors[]; +/** + * @brief List containing all descriptors used by Digital TV MPEG-TS + */ enum descriptors { /* ISO/IEC 13818-1 */ video_stream_descriptor = 0x02, |