1 /*****************************************************************************
3 *****************************************************************************
4 * Copyright (C) 2010 Laurent Aimar
7 * Authors: Laurent Aimar <fenrir _AT_ videolan _DOT_ org>
9 * This program is free software; you can redistribute it and/or modify it
10 * under the terms of the GNU Lesser General Public License as published by
11 * the Free Software Foundation; either version 2.1 of the License, or
12 * (at your option) any later version.
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU Lesser General Public License for more details.
19 * You should have received a copy of the GNU Lesser General Public License
20 * along with this program; if not, write to the Free Software Foundation,
21 * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
22 *****************************************************************************/
25 #define XIPH_MAX_HEADER_COUNT (256)
27 /* Temp ffmpeg vorbis format */
28 static inline bool xiph_IsOldFormat( const void *extra, unsigned int i_extra )
30 if ( i_extra >= 6 && GetWBE( extra ) == 30 )
36 static inline unsigned int xiph_CountHeaders( const void *extra, unsigned int i_extra )
38 const uint8_t *p_extra = (uint8_t*) extra;
39 if ( !i_extra ) return 0;
40 if ( xiph_IsOldFormat( extra, i_extra ) )
42 /* Check headers count */
43 unsigned int overall_len = 6;
44 for ( int i=0; i<3; i++ )
46 uint16_t i_size = GetWBE( extra );
47 p_extra += 2 + i_size;
48 if ( overall_len > i_extra - i_size )
50 overall_len += i_size;
60 static inline int xiph_SplitHeaders(unsigned packet_size[], void * packet[], unsigned *packet_count,
61 unsigned extra_size, const void *extra)
63 const uint8_t *current = (const uint8_t *)extra;
64 const uint8_t *end = ¤t[extra_size];
68 /* Parse the packet count and their sizes */
69 const unsigned count = xiph_CountHeaders( current++, extra_size );
71 *packet_count = count;
73 if ( xiph_IsOldFormat( extra, extra_size ) )
75 uint8_t *p_extra = (uint8_t*) extra;
76 unsigned int overall_len = count << 1;
77 for ( unsigned int i=0; i < count; i++ ) {
78 packet_size[i] = GetWBE( p_extra );
79 packet[i] = p_extra + 2;
80 p_extra += packet_size[i] + 2;
81 if (overall_len > extra_size - packet_size[i])
83 overall_len += packet_size[i];
89 for (unsigned i = 0; i < count - 1; i++) {
94 packet_size[i] += *current;
95 if (*current++ != 255)
98 size += packet_size[i];
100 if (end - current < size)
102 packet_size[count - 1] = end - current - size;
104 for (unsigned i = 0; i < count; i++)
105 if (packet_size[i] > 0) {
106 packet[i] = (void *) current;
107 current += packet_size[i];
113 static inline int xiph_PackHeaders(int *extra_size, void **extra,
114 unsigned packet_size[], const void *packet[], unsigned packet_count )
116 if (packet_count <= 0 || packet_count > XIPH_MAX_HEADER_COUNT)
119 /* Compute the size needed for the whole extra data */
120 unsigned payload_size = 0;
121 unsigned header_size = 1;
122 for (unsigned i = 0; i < packet_count; i++) {
123 payload_size += packet_size[i];
124 if (i < packet_count - 1)
125 header_size += 1 + packet_size[i] / 255;
129 *extra_size = header_size + payload_size;
130 *extra = malloc(*extra_size);
134 /* Write the header */
135 uint8_t *current = (uint8_t*)*extra;
136 *current++ = packet_count - 1;
137 for (unsigned i = 0; i < packet_count - 1; i++) {
138 unsigned t = packet_size[i];
150 /* Copy the payloads */
151 for (unsigned i = 0; i < packet_count; i++) {
152 if (packet_size[i] > 0) {
153 memcpy(current, packet[i], packet_size[i]);
154 current += packet_size[i];
157 assert(current == (uint8_t*)*extra + *extra_size);
161 static inline int xiph_AppendHeaders(int *extra_size, void **extra,
162 unsigned size, const void *data)
164 unsigned packet_size[XIPH_MAX_HEADER_COUNT];
165 void *packet[XIPH_MAX_HEADER_COUNT];
167 if (*extra_size > 0 && *extra) {
168 if (xiph_SplitHeaders(packet_size, packet, &count, *extra_size, *extra))
173 if (count >= XIPH_MAX_HEADER_COUNT)
178 packet_size[count] = size;
179 packet[count] = (void*)data;
180 if (xiph_PackHeaders(extra_size, extra, packet_size,
181 (const void **)packet, count + 1)) {
188 if (*extra_size <= 0)