1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * This file contains the logic to work with MPEG Program-Specific Information.
4 * These are defined both in ISO/IEC 13818-1 (systems) and ETSI EN 300 468.
5 * PSI is carried in the form of table structures, and although each table might
6 * technically be broken into one or more sections, we do not do this here,
7 * hence 'table' and 'section' are interchangeable for vidtv.
8 *
9 * Copyright (C) 2020 Daniel W. S. Almeida
10 */
11
12#ifndef VIDTV_PSI_H
13#define VIDTV_PSI_H
14
15#include <linux/types.h>
16
17/*
18 * all section lengths start immediately after the 'section_length' field
19 * see ISO/IEC 13818-1 : 2000 and ETSI EN 300 468 V 1.10.1 for
20 * reference
21 */
22#define PAT_LEN_UNTIL_LAST_SECTION_NUMBER 5
23#define PMT_LEN_UNTIL_PROGRAM_INFO_LENGTH 9
24#define SDT_LEN_UNTIL_RESERVED_FOR_FUTURE_USE 8
25#define NIT_LEN_UNTIL_NETWORK_DESCRIPTOR_LEN 7
26#define EIT_LEN_UNTIL_LAST_TABLE_ID 11
27#define MAX_SECTION_LEN 1021
28#define EIT_MAX_SECTION_LEN 4093 /* see ETSI 300 468 v.1.10.1 p. 26 */
29#define VIDTV_PAT_PID 0 /* mandated by the specs */
30#define VIDTV_SDT_PID 0x0011 /* mandated by the specs */
31#define VIDTV_NIT_PID 0x0010 /* mandated by the specs */
32#define VIDTV_EIT_PID 0x0012 /*mandated by the specs */
33
34enum vidtv_psi_descriptors {
35	REGISTRATION_DESCRIPTOR	= 0x05, /* See ISO/IEC 13818-1 section 2.6.8 */
36	NETWORK_NAME_DESCRIPTOR = 0x40, /* See ETSI EN 300 468 section 6.2.27 */
37	SERVICE_LIST_DESCRIPTOR = 0x41, /* See ETSI EN 300 468 section 6.2.35 */
38	SERVICE_DESCRIPTOR = 0x48, /* See ETSI EN 300 468 section 6.2.33 */
39	SHORT_EVENT_DESCRIPTOR = 0x4d, /* See ETSI EN 300 468 section 6.2.37 */
40};
41
42enum vidtv_psi_stream_types {
43	STREAM_PRIVATE_DATA = 0x06, /* see ISO/IEC 13818-1 2000 p. 48 */
44};
45
46/*
47 * struct vidtv_psi_desc - A generic PSI descriptor type.
48 * The descriptor length is an 8-bit field specifying the total number of bytes of the data portion
49 * of the descriptor following the byte defining the value of this field.
50 */
51struct vidtv_psi_desc {
52	struct vidtv_psi_desc *next;
53	u8 type;
54	u8 length;
55	u8 data[];
56} __packed;
57
58/*
59 * struct vidtv_psi_desc_service - Service descriptor.
60 * See ETSI EN 300 468 section 6.2.33.
61 */
62struct vidtv_psi_desc_service {
63	struct vidtv_psi_desc *next;
64	u8 type;
65	u8 length;
66
67	u8 service_type;
68	u8 provider_name_len;
69	char *provider_name;
70	u8 service_name_len;
71	char *service_name;
72} __packed;
73
74/*
75 * struct vidtv_psi_desc_registration - A registration descriptor.
76 * See ISO/IEC 13818-1 section 2.6.8
77 */
78struct vidtv_psi_desc_registration {
79	struct vidtv_psi_desc *next;
80	u8 type;
81	u8 length;
82
83	/*
84	 * The format_identifier is a 32-bit value obtained from a Registration
85	 * Authority as designated by ISO/IEC JTC 1/SC 29.
86	 */
87	__be32 format_id;
88	/*
89	 * The meaning of additional_identification_info bytes, if any, are
90	 * defined by the assignee of that format_identifier, and once defined
91	 * they shall not change.
92	 */
93	u8 additional_identification_info[];
94} __packed;
95
96/*
97 * struct vidtv_psi_desc_network_name - A network name descriptor
98 * see ETSI EN 300 468 v1.15.1 section 6.2.27
99 */
100struct vidtv_psi_desc_network_name {
101	struct vidtv_psi_desc *next;
102	u8 type;
103	u8 length;
104	char *network_name;
105} __packed;
106
107struct vidtv_psi_desc_service_list_entry {
108	__be16 service_id;
109	u8 service_type;
110	struct vidtv_psi_desc_service_list_entry *next;
111} __packed;
112
113/*
114 * struct vidtv_psi_desc_service_list - A service list descriptor
115 * see ETSI EN 300 468 v1.15.1 section 6.2.35
116 */
117struct vidtv_psi_desc_service_list {
118	struct vidtv_psi_desc *next;
119	u8 type;
120	u8 length;
121	struct vidtv_psi_desc_service_list_entry *service_list;
122} __packed;
123
124/*
125 * struct vidtv_psi_desc_short_event - A short event descriptor
126 * see ETSI EN 300 468 v1.15.1 section 6.2.37
127 */
128struct vidtv_psi_desc_short_event {
129	struct vidtv_psi_desc *next;
130	u8 type;
131	u8 length;
132	char *iso_language_code;
133	u8 event_name_len;
134	char *event_name;
135	u8 text_len;
136	char *text;
137} __packed;
138
139struct vidtv_psi_desc_short_event
140*vidtv_psi_short_event_desc_init(struct vidtv_psi_desc *head,
141				 char *iso_language_code,
142				 char *event_name,
143				 char *text);
144
145/*
146 * struct vidtv_psi_table_header - A header that is present for all PSI tables.
147 */
148struct vidtv_psi_table_header {
149	u8  table_id;
150
151	__be16 bitfield; /* syntax: 1, zero: 1, one: 2, section_length: 13 */
152
153	__be16 id; /* TS ID */
154	u8  current_next:1;
155	u8  version:5;
156	u8  one2:2;
157	u8  section_id;	/* section_number */
158	u8  last_section; /* last_section_number */
159} __packed;
160
161/*
162 * struct vidtv_psi_table_pat_program - A single program in the PAT
163 * See ISO/IEC 13818-1 : 2000 p.43
164 */
165struct vidtv_psi_table_pat_program {
166	__be16 service_id;
167	__be16 bitfield; /* reserved: 3, program_map_pid/network_pid: 13 */
168	struct vidtv_psi_table_pat_program *next;
169} __packed;
170
171/*
172 * struct vidtv_psi_table_pat - The Program Allocation Table (PAT)
173 * See ISO/IEC 13818-1 : 2000 p.43
174 */
175struct vidtv_psi_table_pat {
176	struct vidtv_psi_table_header header;
177	u16 num_pat;
178	u16 num_pmt;
179	struct vidtv_psi_table_pat_program *program;
180} __packed;
181
182/*
183 * struct vidtv_psi_table_sdt_service - Represents a service in the SDT.
184 * see ETSI EN 300 468 v1.15.1 section 5.2.3.
185 */
186struct vidtv_psi_table_sdt_service {
187	__be16 service_id;
188	u8 EIT_present_following:1;
189	u8 EIT_schedule:1;
190	u8 reserved:6;
191	__be16 bitfield; /* running_status: 3, free_ca:1, desc_loop_len:12 */
192	struct vidtv_psi_desc *descriptor;
193	struct vidtv_psi_table_sdt_service *next;
194} __packed;
195
196/*
197 * struct vidtv_psi_table_sdt - Represents the Service Description Table
198 * see ETSI EN 300 468 v1.15.1 section 5.2.3.
199 */
200
201struct vidtv_psi_table_sdt {
202	struct vidtv_psi_table_header header;
203	__be16 network_id; /* original_network_id */
204	u8  reserved;
205	struct vidtv_psi_table_sdt_service *service;
206} __packed;
207
208/*
209 * enum service_running_status - Status of a SDT service.
210 * see ETSI EN 300 468 v1.15.1 section 5.2.3 table 6.
211 */
212enum service_running_status {
213	RUNNING = 0x4,
214};
215
216/*
217 * enum service_type - The type of a SDT service.
218 * see ETSI EN 300 468 v1.15.1 section 6.2.33, table 81.
219 */
220enum service_type {
221	/* see ETSI EN 300 468 v1.15.1 p. 77 */
222	DIGITAL_TELEVISION_SERVICE = 0x1,
223	DIGITAL_RADIO_SOUND_SERVICE = 0X2,
224};
225
226/*
227 * struct vidtv_psi_table_pmt_stream - A single stream in the PMT.
228 * See ISO/IEC 13818-1 : 2000 p.46.
229 */
230struct vidtv_psi_table_pmt_stream {
231	u8 type;
232	__be16 bitfield; /* reserved: 3, elementary_pid: 13 */
233	__be16 bitfield2; /*reserved: 4, zero: 2, desc_length: 10 */
234	struct vidtv_psi_desc *descriptor;
235	struct vidtv_psi_table_pmt_stream *next;
236} __packed;
237
238/*
239 * struct vidtv_psi_table_pmt - The Program Map Table (PMT).
240 * See ISO/IEC 13818-1 : 2000 p.46.
241 */
242struct vidtv_psi_table_pmt {
243	struct vidtv_psi_table_header header;
244	__be16 bitfield; /* reserved:3, pcr_pid: 13 */
245	__be16 bitfield2; /* reserved: 4, zero: 2, desc_len: 10 */
246	struct vidtv_psi_desc *descriptor;
247	struct vidtv_psi_table_pmt_stream *stream;
248} __packed;
249
250/**
251 * struct psi_write_args - Arguments for the PSI packetizer.
252 * @dest_buf: The buffer to write into.
253 * @from: PSI data to be copied.
254 * @len: How much to write.
255 * @dest_offset: where to start writing in the dest_buffer.
256 * @pid: TS packet ID.
257 * @new_psi_section: Set when starting a table section.
258 * @continuity_counter: Incremented on every new packet.
259 * @is_crc: Set when writing the CRC at the end.
260 * @dest_buf_sz: The size of the dest_buffer
261 * @crc: a pointer to store the crc for this chunk
262 */
263struct psi_write_args {
264	void *dest_buf;
265	void *from;
266	size_t len;
267	u32 dest_offset;
268	u16 pid;
269	bool new_psi_section;
270	u8 *continuity_counter;
271	bool is_crc;
272	u32 dest_buf_sz;
273	u32 *crc;
274};
275
276/**
277 * struct desc_write_args - Arguments in order to write a descriptor.
278 * @dest_buf: The buffer to write into.
279 * @dest_offset: where to start writing in the dest_buffer.
280 * @desc: A pointer to the descriptor
281 * @pid: TS packet ID.
282 * @continuity_counter: Incremented on every new packet.
283 * @dest_buf_sz: The size of the dest_buffer
284 * @crc: a pointer to store the crc for this chunk
285 */
286struct desc_write_args {
287	void *dest_buf;
288	u32 dest_offset;
289	struct vidtv_psi_desc *desc;
290	u16 pid;
291	u8 *continuity_counter;
292	u32 dest_buf_sz;
293	u32 *crc;
294};
295
296/**
297 * struct crc32_write_args - Arguments in order to write the CRC at the end of
298 * the PSI tables.
299 * @dest_buf: The buffer to write into.
300 * @dest_offset: where to start writing in the dest_buffer.
301 * @crc: the CRC value to write
302 * @pid: TS packet ID.
303 * @continuity_counter: Incremented on every new packet.
304 * @dest_buf_sz: The size of the dest_buffer
305 */
306struct crc32_write_args {
307	void *dest_buf;
308	u32 dest_offset;
309	__be32 crc;
310	u16 pid;
311	u8 *continuity_counter;
312	u32 dest_buf_sz;
313};
314
315/**
316 * struct header_write_args - Arguments in order to write the common table
317 * header
318 * @dest_buf: The buffer to write into.
319 * @dest_offset: where to start writing in the dest_buffer.
320 * @h: a pointer to the header.
321 * @pid: TS packet ID.
322 * @continuity_counter: Incremented on every new packet.
323 * @dest_buf_sz: The size of the dest_buffer
324 * @crc: a pointer to store the crc for this chunk
325 */
326struct header_write_args {
327	void *dest_buf;
328	u32 dest_offset;
329	struct vidtv_psi_table_header *h;
330	u16 pid;
331	u8 *continuity_counter;
332	u32 dest_buf_sz;
333	u32 *crc;
334};
335
336struct vidtv_psi_desc_service *vidtv_psi_service_desc_init(struct vidtv_psi_desc *head,
337							   enum service_type service_type,
338							   char *service_name,
339							   char *provider_name);
340
341struct vidtv_psi_desc_registration
342*vidtv_psi_registration_desc_init(struct vidtv_psi_desc *head,
343				  __be32 format_id,
344				  u8 *additional_ident_info,
345				  u32 additional_info_len);
346
347struct vidtv_psi_desc_network_name
348*vidtv_psi_network_name_desc_init(struct vidtv_psi_desc *head, char *network_name);
349
350struct vidtv_psi_desc_service_list
351*vidtv_psi_service_list_desc_init(struct vidtv_psi_desc *head,
352				  struct vidtv_psi_desc_service_list_entry *entry);
353
354struct vidtv_psi_table_pat_program
355*vidtv_psi_pat_program_init(struct vidtv_psi_table_pat_program *head,
356			    u16 service_id,
357			    u16 program_map_pid);
358
359struct vidtv_psi_table_pmt_stream*
360vidtv_psi_pmt_stream_init(struct vidtv_psi_table_pmt_stream *head,
361			  enum vidtv_psi_stream_types stream_type,
362			  u16 es_pid);
363
364struct vidtv_psi_table_pat *vidtv_psi_pat_table_init(u16 transport_stream_id);
365
366struct vidtv_psi_table_pmt *vidtv_psi_pmt_table_init(u16 program_number,
367						     u16 pcr_pid);
368
369struct vidtv_psi_table_sdt *vidtv_psi_sdt_table_init(u16 network_id,
370						     u16 transport_stream_id);
371
372struct vidtv_psi_table_sdt_service*
373vidtv_psi_sdt_service_init(struct vidtv_psi_table_sdt_service *head,
374			   u16 service_id,
375			   bool eit_schedule,
376			   bool eit_present_following);
377
378void
379vidtv_psi_desc_destroy(struct vidtv_psi_desc *desc);
380
381void
382vidtv_psi_pat_program_destroy(struct vidtv_psi_table_pat_program *p);
383
384void
385vidtv_psi_pat_table_destroy(struct vidtv_psi_table_pat *p);
386
387void
388vidtv_psi_pmt_stream_destroy(struct vidtv_psi_table_pmt_stream *s);
389
390void
391vidtv_psi_pmt_table_destroy(struct vidtv_psi_table_pmt *pmt);
392
393void
394vidtv_psi_sdt_table_destroy(struct vidtv_psi_table_sdt *sdt);
395
396void
397vidtv_psi_sdt_service_destroy(struct vidtv_psi_table_sdt_service *service);
398
399/**
400 * vidtv_psi_sdt_service_assign - Assigns the service loop to the SDT.
401 * @sdt: The SDT to assign to.
402 * @service: The service loop (one or more services)
403 *
404 * This will free the previous service loop in the table.
405 * This will assign ownership of the service loop to the table, i.e. the table
406 * will free this service loop when a call to its destroy function is made.
407 */
408void
409vidtv_psi_sdt_service_assign(struct vidtv_psi_table_sdt *sdt,
410			     struct vidtv_psi_table_sdt_service *service);
411
412/**
413 * vidtv_psi_desc_assign - Assigns a descriptor loop at some point
414 * @to: Where to assign this descriptor loop to
415 * @desc: The descriptor loop that will be assigned.
416 *
417 * This will free the loop in 'to', if any.
418 */
419void vidtv_psi_desc_assign(struct vidtv_psi_desc **to,
420			   struct vidtv_psi_desc *desc);
421
422/**
423 * vidtv_pmt_desc_assign - Assigns a descriptor loop at some point in a PMT section.
424 * @pmt: The PMT section that will contain the descriptor loop
425 * @to: Where in the PMT to assign this descriptor loop to
426 * @desc: The descriptor loop that will be assigned.
427 *
428 * This will free the loop in 'to', if any.
429 * This will assign ownership of the loop to the table, i.e. the table
430 * will free this loop when a call to its destroy function is made.
431 */
432void vidtv_pmt_desc_assign(struct vidtv_psi_table_pmt *pmt,
433			   struct vidtv_psi_desc **to,
434			   struct vidtv_psi_desc *desc);
435
436/**
437 * vidtv_sdt_desc_assign - Assigns a descriptor loop at some point in a SDT.
438 * @sdt: The SDT that will contain the descriptor loop
439 * @to: Where in the PMT to assign this descriptor loop to
440 * @desc: The descriptor loop that will be assigned.
441 *
442 * This will free the loop in 'to', if any.
443 * This will assign ownership of the loop to the table, i.e. the table
444 * will free this loop when a call to its destroy function is made.
445 */
446void vidtv_sdt_desc_assign(struct vidtv_psi_table_sdt *sdt,
447			   struct vidtv_psi_desc **to,
448			   struct vidtv_psi_desc *desc);
449
450/**
451 * vidtv_psi_pat_program_assign - Assigns the program loop to the PAT.
452 * @pat: The PAT to assign to.
453 * @p: The program loop (one or more programs)
454 *
455 * This will free the previous program loop in the table.
456 * This will assign ownership of the program loop to the table, i.e. the table
457 * will free this program loop when a call to its destroy function is made.
458 */
459void vidtv_psi_pat_program_assign(struct vidtv_psi_table_pat *pat,
460				  struct vidtv_psi_table_pat_program *p);
461
462/**
463 * vidtv_psi_pmt_stream_assign - Assigns the stream loop to the PAT.
464 * @pmt: The PMT to assign to.
465 * @s: The stream loop (one or more streams)
466 *
467 * This will free the previous stream loop in the table.
468 * This will assign ownership of the stream loop to the table, i.e. the table
469 * will free this stream loop when a call to its destroy function is made.
470 */
471void vidtv_psi_pmt_stream_assign(struct vidtv_psi_table_pmt *pmt,
472				 struct vidtv_psi_table_pmt_stream *s);
473
474struct vidtv_psi_desc *vidtv_psi_desc_clone(struct vidtv_psi_desc *desc);
475
476/**
477 * vidtv_psi_pmt_create_sec_for_each_pat_entry - Create a PMT section for each
478 * program found in the PAT
479 * @pat: The PAT to look for programs.
480 * @pcr_pid: packet ID for the PCR to be used for the program described in this
481 * PMT section
482 */
483struct vidtv_psi_table_pmt**
484vidtv_psi_pmt_create_sec_for_each_pat_entry(struct vidtv_psi_table_pat *pat, u16 pcr_pid);
485
486/**
487 * vidtv_psi_pmt_get_pid - Get the TS PID for a PMT section.
488 * @section: The PMT section whose PID we want to retrieve.
489 * @pat: The PAT table to look into.
490 *
491 * Returns: the TS PID for 'section'
492 */
493u16 vidtv_psi_pmt_get_pid(struct vidtv_psi_table_pmt *section,
494			  struct vidtv_psi_table_pat *pat);
495
496/**
497 * vidtv_psi_pat_table_update_sec_len - Recompute and update the PAT section length.
498 * @pat: The PAT whose length is to be updated.
499 *
500 * This will traverse the table and accumulate the length of its components,
501 * which is then used to replace the 'section_length' field.
502 *
503 * If section_length > MAX_SECTION_LEN, the operation fails.
504 */
505void vidtv_psi_pat_table_update_sec_len(struct vidtv_psi_table_pat *pat);
506
507/**
508 * vidtv_psi_pmt_table_update_sec_len - Recompute and update the PMT section length.
509 * @pmt: The PMT whose length is to be updated.
510 *
511 * This will traverse the table and accumulate the length of its components,
512 * which is then used to replace the 'section_length' field.
513 *
514 * If section_length > MAX_SECTION_LEN, the operation fails.
515 */
516void vidtv_psi_pmt_table_update_sec_len(struct vidtv_psi_table_pmt *pmt);
517
518/**
519 * vidtv_psi_sdt_table_update_sec_len - Recompute and update the SDT section length.
520 * @sdt: The SDT whose length is to be updated.
521 *
522 * This will traverse the table and accumulate the length of its components,
523 * which is then used to replace the 'section_length' field.
524 *
525 * If section_length > MAX_SECTION_LEN, the operation fails.
526 */
527void vidtv_psi_sdt_table_update_sec_len(struct vidtv_psi_table_sdt *sdt);
528
529/**
530 * struct vidtv_psi_pat_write_args - Arguments for writing a PAT table
531 * @buf: The destination buffer.
532 * @offset: The offset into the destination buffer.
533 * @pat: A pointer to the PAT.
534 * @buf_sz: The size of the destination buffer.
535 * @continuity_counter: A pointer to the CC. Incremented on every new packet.
536 *
537 */
538struct vidtv_psi_pat_write_args {
539	char *buf;
540	u32 offset;
541	struct vidtv_psi_table_pat *pat;
542	u32 buf_sz;
543	u8 *continuity_counter;
544};
545
546/**
547 * vidtv_psi_pat_write_into - Write PAT as MPEG-TS packets into a buffer.
548 * @args: An instance of struct vidtv_psi_pat_write_args
549 *
550 * This function writes the MPEG TS packets for a PAT table into a buffer.
551 * Calling code will usually generate the PAT via a call to its init function
552 * and thus is responsible for freeing it.
553 *
554 * Return: The number of bytes written into the buffer. This is NOT
555 * equal to the size of the PAT, since more space is needed for TS headers during TS
556 * encapsulation.
557 */
558u32 vidtv_psi_pat_write_into(struct vidtv_psi_pat_write_args *args);
559
560/**
561 * struct vidtv_psi_sdt_write_args - Arguments for writing a SDT table
562 * @buf: The destination buffer.
563 * @offset: The offset into the destination buffer.
564 * @sdt: A pointer to the SDT.
565 * @buf_sz: The size of the destination buffer.
566 * @continuity_counter: A pointer to the CC. Incremented on every new packet.
567 *
568 */
569
570struct vidtv_psi_sdt_write_args {
571	char *buf;
572	u32 offset;
573	struct vidtv_psi_table_sdt *sdt;
574	u32 buf_sz;
575	u8 *continuity_counter;
576};
577
578/**
579 * vidtv_psi_sdt_write_into - Write SDT as MPEG-TS packets into a buffer.
580 * @args: an instance of struct vidtv_psi_sdt_write_args
581 *
582 * This function writes the MPEG TS packets for a SDT table into a buffer.
583 * Calling code will usually generate the SDT via a call to its init function
584 * and thus is responsible for freeing it.
585 *
586 * Return: The number of bytes written into the buffer. This is NOT
587 * equal to the size of the SDT, since more space is needed for TS headers during TS
588 * encapsulation.
589 */
590u32 vidtv_psi_sdt_write_into(struct vidtv_psi_sdt_write_args *args);
591
592/**
593 * struct vidtv_psi_pmt_write_args - Arguments for writing a PMT section
594 * @buf: The destination buffer.
595 * @offset: The offset into the destination buffer.
596 * @pmt: A pointer to the PMT.
597 * @pid: Program ID
598 * @buf_sz: The size of the destination buffer.
599 * @continuity_counter: A pointer to the CC. Incremented on every new packet.
600 * @pcr_pid: The TS PID used for the PSI packets. All channels will share the
601 * same PCR.
602 */
603struct vidtv_psi_pmt_write_args {
604	char *buf;
605	u32 offset;
606	struct vidtv_psi_table_pmt *pmt;
607	u16 pid;
608	u32 buf_sz;
609	u8 *continuity_counter;
610	u16 pcr_pid;
611};
612
613/**
614 * vidtv_psi_pmt_write_into - Write PMT as MPEG-TS packets into a buffer.
615 * @args: an instance of struct vidtv_psi_pmt_write_args
616 *
617 * This function writes the MPEG TS packets for a PMT section into a buffer.
618 * Calling code will usually generate the PMT section via a call to its init function
619 * and thus is responsible for freeing it.
620 *
621 * Return: The number of bytes written into the buffer. This is NOT
622 * equal to the size of the PMT section, since more space is needed for TS headers
623 * during TS encapsulation.
624 */
625u32 vidtv_psi_pmt_write_into(struct vidtv_psi_pmt_write_args *args);
626
627/**
628 * vidtv_psi_find_pmt_sec - Finds the PMT section for 'program_num'
629 * @pmt_sections: The sections to look into.
630 * @nsections: The number of sections.
631 * @program_num: The 'program_num' from PAT pointing to a PMT section.
632 *
633 * Return: A pointer to the PMT, if found, or NULL.
634 */
635struct vidtv_psi_table_pmt *vidtv_psi_find_pmt_sec(struct vidtv_psi_table_pmt **pmt_sections,
636						   u16 nsections,
637						   u16 program_num);
638
639u16 vidtv_psi_get_pat_program_pid(struct vidtv_psi_table_pat_program *p);
640u16 vidtv_psi_pmt_stream_get_elem_pid(struct vidtv_psi_table_pmt_stream *s);
641
642/**
643 * struct vidtv_psi_table_transport - A entry in the TS loop for the NIT and/or other tables.
644 * See ETSI 300 468 section 5.2.1
645 * @transport_id: The TS ID being described
646 * @network_id: The network_id that contains the TS ID
647 * @bitfield: Contains the descriptor loop length
648 * @descriptor: A descriptor loop
649 * @next: Pointer to the next entry
650 *
651 */
652struct vidtv_psi_table_transport {
653	__be16 transport_id;
654	__be16 network_id;
655	__be16 bitfield; /* desc_len: 12, reserved: 4 */
656	struct vidtv_psi_desc *descriptor;
657	struct vidtv_psi_table_transport *next;
658} __packed;
659
660/**
661 * struct vidtv_psi_table_nit - A Network Information Table (NIT). See ETSI 300
662 * 468 section 5.2.1
663 * @header: A PSI table header
664 * @bitfield: Contains the network descriptor length
665 * @descriptor: A descriptor loop describing the network
666 * @bitfield2: Contains the transport stream loop length
667 * @transport: The transport stream loop
668 *
669 */
670struct vidtv_psi_table_nit {
671	struct vidtv_psi_table_header header;
672	__be16 bitfield; /* network_desc_len: 12, reserved:4 */
673	struct vidtv_psi_desc *descriptor;
674	__be16 bitfield2; /* ts_loop_len: 12, reserved: 4 */
675	struct vidtv_psi_table_transport *transport;
676} __packed;
677
678struct vidtv_psi_table_nit
679*vidtv_psi_nit_table_init(u16 network_id,
680			  u16 transport_stream_id,
681			  char *network_name,
682			  struct vidtv_psi_desc_service_list_entry *service_list);
683
684/**
685 * struct vidtv_psi_nit_write_args - Arguments for writing a NIT section
686 * @buf: The destination buffer.
687 * @offset: The offset into the destination buffer.
688 * @nit: A pointer to the NIT
689 * @buf_sz: The size of the destination buffer.
690 * @continuity_counter: A pointer to the CC. Incremented on every new packet.
691 *
692 */
693struct vidtv_psi_nit_write_args {
694	char *buf;
695	u32 offset;
696	struct vidtv_psi_table_nit *nit;
697	u32 buf_sz;
698	u8 *continuity_counter;
699};
700
701/**
702 * vidtv_psi_nit_write_into - Write NIT as MPEG-TS packets into a buffer.
703 * @args: an instance of struct vidtv_psi_nit_write_args
704 *
705 * This function writes the MPEG TS packets for a NIT table into a buffer.
706 * Calling code will usually generate the NIT via a call to its init function
707 * and thus is responsible for freeing it.
708 *
709 * Return: The number of bytes written into the buffer. This is NOT
710 * equal to the size of the NIT, since more space is needed for TS headers during TS
711 * encapsulation.
712 */
713u32 vidtv_psi_nit_write_into(struct vidtv_psi_nit_write_args *args);
714
715void vidtv_psi_nit_table_destroy(struct vidtv_psi_table_nit *nit);
716
717/*
718 * struct vidtv_psi_desc_short_event - A short event descriptor
719 * see ETSI EN 300 468 v1.15.1 section 6.2.37
720 */
721struct vidtv_psi_table_eit_event {
722	__be16 event_id;
723	u8 start_time[5];
724	u8 duration[3];
725	__be16 bitfield; /* desc_length: 12, free_CA_mode: 1, running_status: 1 */
726	struct vidtv_psi_desc *descriptor;
727	struct vidtv_psi_table_eit_event *next;
728} __packed;
729
730/*
731 * struct vidtv_psi_table_eit - A Event Information Table (EIT)
732 * See ETSI 300 468 section 5.2.4
733 */
734struct vidtv_psi_table_eit {
735	struct vidtv_psi_table_header header;
736	__be16 transport_id;
737	__be16 network_id;
738	u8 last_segment;
739	u8 last_table_id;
740	struct vidtv_psi_table_eit_event *event;
741} __packed;
742
743struct vidtv_psi_table_eit
744*vidtv_psi_eit_table_init(u16 network_id,
745			  u16 transport_stream_id,
746			  __be16 service_id);
747
748/**
749 * struct vidtv_psi_eit_write_args - Arguments for writing an EIT section
750 * @buf: The destination buffer.
751 * @offset: The offset into the destination buffer.
752 * @eit: A pointer to the EIT
753 * @buf_sz: The size of the destination buffer.
754 * @continuity_counter: A pointer to the CC. Incremented on every new packet.
755 *
756 */
757struct vidtv_psi_eit_write_args {
758	char *buf;
759	u32 offset;
760	struct vidtv_psi_table_eit *eit;
761	u32 buf_sz;
762	u8 *continuity_counter;
763};
764
765/**
766 * vidtv_psi_eit_write_into - Write EIT as MPEG-TS packets into a buffer.
767 * @args: an instance of struct vidtv_psi_nit_write_args
768 *
769 * This function writes the MPEG TS packets for a EIT table into a buffer.
770 * Calling code will usually generate the EIT via a call to its init function
771 * and thus is responsible for freeing it.
772 *
773 * Return: The number of bytes written into the buffer. This is NOT
774 * equal to the size of the EIT, since more space is needed for TS headers during TS
775 * encapsulation.
776 */
777u32 vidtv_psi_eit_write_into(struct vidtv_psi_eit_write_args *args);
778
779void vidtv_psi_eit_table_destroy(struct vidtv_psi_table_eit *eit);
780
781/**
782 * vidtv_psi_eit_table_update_sec_len - Recompute and update the EIT section length.
783 * @eit: The EIT whose length is to be updated.
784 *
785 * This will traverse the table and accumulate the length of its components,
786 * which is then used to replace the 'section_length' field.
787 *
788 * If section_length > EIT_MAX_SECTION_LEN, the operation fails.
789 */
790void vidtv_psi_eit_table_update_sec_len(struct vidtv_psi_table_eit *eit);
791
792/**
793 * vidtv_psi_eit_event_assign - Assigns the event loop to the EIT.
794 * @eit: The EIT to assign to.
795 * @e: The event loop
796 *
797 * This will free the previous event loop in the table.
798 * This will assign ownership of the stream loop to the table, i.e. the table
799 * will free this stream loop when a call to its destroy function is made.
800 */
801void vidtv_psi_eit_event_assign(struct vidtv_psi_table_eit *eit,
802				struct vidtv_psi_table_eit_event *e);
803
804struct vidtv_psi_table_eit_event
805*vidtv_psi_eit_event_init(struct vidtv_psi_table_eit_event *head, u16 event_id);
806
807void vidtv_psi_eit_event_destroy(struct vidtv_psi_table_eit_event *e);
808
809#endif // VIDTV_PSI_H
810