1 /*
2 * section and descriptor parser
3 *
4 * Copyright (C) 2005 Kenneth Aafloy (kenneth@linuxtv.org)
5 * Copyright (C) 2005 Andrew de Quincey (adq_dvb@lidskialf.net)
6 *
7 * This library is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
11 *
12 * This library is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with this library; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
20 */
21
22 #ifndef _UCSI_ATSC_TVCT_SECTION_H
23 #define _UCSI_ATSC_TVCT_SECTION_H 1
24
25 #ifdef __cplusplus
26 extern "C"
27 {
28 #endif
29
30 #include <libucsi/atsc/section.h>
31
32 /**
33 * atsc_tvct_section structure.
34 */
35 struct atsc_tvct_section {
36 struct atsc_section_psip head;
37
38 uint8_t num_channels_in_section;
39 /* struct atsc_tvct_channel channels[] */
40 /* struct atsc_tvct_channel_part2 part2 */
41 } __ucsi_packed;
42
43 struct atsc_tvct_channel {
44 uint16_t short_name[7]; // UTF-16 network ordered
45 EBIT4(uint32_t reserved : 4; ,
46 uint32_t major_channel_number :10; ,
47 uint32_t minor_channel_number :10; ,
48 uint32_t modulation_mode : 8; );
49 uint32_t carrier_frequency;
50 uint16_t channel_TSID;
51 uint16_t program_number;
52 EBIT7(uint16_t ETM_location : 2; ,
53 uint16_t access_controlled : 1; ,
54 uint16_t hidden : 1; ,
55 uint16_t reserved1 : 2; ,
56 uint16_t hide_guide : 1; ,
57 uint16_t reserved2 : 3; ,
58 uint16_t service_type : 6; );
59 uint16_t source_id;
60 EBIT2(uint16_t reserved3 : 6; ,
61 uint16_t descriptors_length :10; );
62 /* struct descriptor descriptors[] */
63 } __ucsi_packed;
64
65 struct atsc_tvct_section_part2 {
66 EBIT2(uint16_t reserved : 6; ,
67 uint16_t descriptors_length :10; );
68 /* struct descriptor descriptors[] */
69 } __ucsi_packed;
70
71 static inline struct atsc_tvct_channel *atsc_tvct_section_channels_first(struct atsc_tvct_section *tvct);
72 static inline struct atsc_tvct_channel *
73 atsc_tvct_section_channels_next(struct atsc_tvct_section *tvct, struct atsc_tvct_channel *pos, int idx);
74
75 /**
76 * Process a atsc_tvct_section.
77 *
78 * @param section Pointer to an atsc_section_psip structure.
79 * @return atsc_tvct_section pointer, or NULL on error.
80 */
81 struct atsc_tvct_section *atsc_tvct_section_codec(struct atsc_section_psip *section);
82
83 /**
84 * Accessor for the transport_stream_id field of a TVCT.
85 *
86 * @param tvct TVCT pointer.
87 * @return The transport_stream_id.
88 */
atsc_tvct_section_transport_stream_id(struct atsc_tvct_section * tvct)89 static inline uint16_t atsc_tvct_section_transport_stream_id(struct atsc_tvct_section *tvct)
90 {
91 return tvct->head.ext_head.table_id_ext;
92 }
93
94 /**
95 * Iterator for the channels field in an atsc_tvct_section.
96 *
97 * @param mgt atsc_tvct_section pointer.
98 * @param pos Variable containing a pointer to the current atsc_tvct_channel.
99 * @param idx Integer used to count which channel we in.
100 */
101 #define atsc_tvct_section_channels_for_each(mgt, pos, idx) \
102 for ((pos) = atsc_tvct_section_channels_first(mgt), idx=0; \
103 (pos); \
104 (pos) = atsc_tvct_section_channels_next(mgt, pos, ++idx))
105
106 /**
107 * Iterator for the descriptors field in a atsc_tvct_channel structure.
108 *
109 * @param channel atsc_tvct_channel pointer.
110 * @param pos Variable containing a pointer to the current descriptor.
111 */
112 #define atsc_tvct_channel_descriptors_for_each(channel, pos) \
113 for ((pos) = atsc_tvct_channel_descriptors_first(channel); \
114 (pos); \
115 (pos) = atsc_tvct_channel_descriptors_next(channel, pos))
116
117 /**
118 * Accessor for the second part of an atsc_tvct_section.
119 *
120 * @param mgt atsc_tvct_section pointer.
121 * @return atsc_tvct_section_part2 pointer.
122 */
123 static inline struct atsc_tvct_section_part2 *
atsc_tvct_section_part2(struct atsc_tvct_section * mgt)124 atsc_tvct_section_part2(struct atsc_tvct_section *mgt)
125 {
126 int pos = sizeof(struct atsc_tvct_section);
127
128 struct atsc_tvct_channel *cur_channel;
129 int idx;
130 atsc_tvct_section_channels_for_each(mgt, cur_channel, idx) {
131 pos += sizeof(struct atsc_tvct_channel);
132 pos += cur_channel->descriptors_length;
133 }
134
135 return (struct atsc_tvct_section_part2 *) (((uint8_t*) mgt) + pos);
136 }
137
138 /**
139 * Iterator for the descriptors field in a atsc_tvct_section structure.
140 *
141 * @param part2 atsc_tvct_section_part2 pointer.
142 * @param pos Variable containing a pointer to the current descriptor.
143 */
144 #define atsc_tvct_section_part2_descriptors_for_each(part2, pos) \
145 for ((pos) = atsc_tvct_section_part2_descriptors_first(part2); \
146 (pos); \
147 (pos) = atsc_tvct_section_part2_descriptors_next(part2, pos))
148
149
150
151
152
153
154
155
156
157
158
159 /******************************** PRIVATE CODE ********************************/
160 static inline struct atsc_tvct_channel *
atsc_tvct_section_channels_first(struct atsc_tvct_section * tvct)161 atsc_tvct_section_channels_first(struct atsc_tvct_section *tvct)
162 {
163 size_t pos = sizeof(struct atsc_tvct_section);
164
165 if (tvct->num_channels_in_section == 0)
166 return NULL;
167
168 return (struct atsc_tvct_channel*) (((uint8_t *) tvct) + pos);
169 }
170
171 static inline struct atsc_tvct_channel *
atsc_tvct_section_channels_next(struct atsc_tvct_section * tvct,struct atsc_tvct_channel * pos,int idx)172 atsc_tvct_section_channels_next(struct atsc_tvct_section *tvct,
173 struct atsc_tvct_channel *pos,
174 int idx)
175 {
176 if (idx >= tvct->num_channels_in_section)
177 return NULL;
178
179 return (struct atsc_tvct_channel *)
180 (((uint8_t*) pos) + sizeof(struct atsc_tvct_channel) + pos->descriptors_length);
181 }
182
183 static inline struct descriptor *
atsc_tvct_channel_descriptors_first(struct atsc_tvct_channel * channel)184 atsc_tvct_channel_descriptors_first(struct atsc_tvct_channel *channel)
185 {
186 size_t pos = sizeof(struct atsc_tvct_channel);
187
188 if (channel->descriptors_length == 0)
189 return NULL;
190
191 return (struct descriptor*) (((uint8_t *) channel) + pos);
192 }
193
194 static inline struct descriptor *
atsc_tvct_channel_descriptors_next(struct atsc_tvct_channel * channel,struct descriptor * pos)195 atsc_tvct_channel_descriptors_next(struct atsc_tvct_channel *channel,
196 struct descriptor *pos)
197 {
198 return next_descriptor((uint8_t*) channel + sizeof(struct atsc_tvct_channel),
199 channel->descriptors_length,
200 pos);
201 }
202
203 static inline struct descriptor *
atsc_tvct_section_part2_descriptors_first(struct atsc_tvct_section_part2 * part2)204 atsc_tvct_section_part2_descriptors_first(struct atsc_tvct_section_part2 *part2)
205 {
206 size_t pos = sizeof(struct atsc_tvct_section_part2);
207
208 if (part2->descriptors_length == 0)
209 return NULL;
210
211 return (struct descriptor*) (((uint8_t *) part2) + pos);
212 }
213
214 static inline struct descriptor *
atsc_tvct_section_part2_descriptors_next(struct atsc_tvct_section_part2 * part2,struct descriptor * pos)215 atsc_tvct_section_part2_descriptors_next(struct atsc_tvct_section_part2 *part2,
216 struct descriptor *pos)
217 {
218 return next_descriptor((uint8_t*) part2 + sizeof(struct atsc_tvct_section_part2),
219 part2->descriptors_length,
220 pos);
221 }
222
223 #ifdef __cplusplus
224 }
225 #endif
226
227 #endif
228