1 /*****************************************************************************
2 * vlc_boxes.h : Boxes/Atoms handling helpers
3 *****************************************************************************
4 * Copyright (C) 2001, 2002, 2003, 2006, 2015 VLC authors and VideoLAN
5 *
6 * Authors: Laurent Aimar <fenrir@via.ecp.fr>
7 * Gildas Bazin <gbazin at videolan dot org>
8 * Rafaël Carré <funman at videolan dot org>
9 *
10 * This program is free software; you can redistribute it and/or modify it
11 * under the terms of the GNU Lesser General Public License as published by
12 * the Free Software Foundation; either version 2.1 of the License, or
13 * (at your option) any later version.
14 *
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU Lesser General Public License for more details.
19 *
20 * You should have received a copy of the GNU Lesser General Public License
21 * along with this program; if not, write to the Free Software Foundation,
22 * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
23 *****************************************************************************/
24 #ifndef VLC_BOXES_H
25 #define VLC_BOXES_H
26
27 #include <vlc_common.h>
28 #include <vlc_block.h>
29
30 /**
31 * \file
32 * This file defines functions, structures for handling boxes/atoms in vlc
33 */
34
35 typedef struct bo_t
36 {
37 block_t *b;
38 size_t basesize;
39 } bo_t;
40
bo_init(bo_t * p_bo,int i_size)41 static inline bool bo_init(bo_t *p_bo, int i_size)
42 {
43 p_bo->b = block_Alloc(i_size);
44 if (p_bo->b == NULL)
45 return false;
46
47 p_bo->b->i_buffer = 0;
48 p_bo->basesize = i_size;
49
50 return true;
51 }
52
bo_deinit(bo_t * p_bo)53 static inline void bo_deinit(bo_t *p_bo)
54 {
55 if(p_bo->b)
56 block_Release(p_bo->b);
57 }
58
bo_free(bo_t * p_bo)59 static inline void bo_free(bo_t *p_bo)
60 {
61 if(!p_bo)
62 return;
63 bo_deinit(p_bo);
64 free(p_bo);
65 }
66
bo_extend(bo_t * p_bo,size_t i_total)67 static inline int bo_extend(bo_t *p_bo, size_t i_total)
68 {
69 if(!p_bo->b)
70 return false;
71 const size_t i_size = p_bo->b->i_size - (p_bo->b->p_buffer - p_bo->b->p_start);
72 if (i_total >= i_size)
73 {
74 int i_growth = p_bo->basesize;
75 while(i_total >= i_size + i_growth)
76 i_growth += p_bo->basesize;
77
78 int i = p_bo->b->i_buffer; /* Realloc would set payload size == buffer size */
79 p_bo->b = block_Realloc(p_bo->b, 0, i_size + i_growth);
80 if (!p_bo->b)
81 return false;
82 p_bo->b->i_buffer = i;
83 }
84 return true;
85 }
86
87 #define BO_SET_DECL_S(func, handler, type) static inline bool func(bo_t *p_bo, size_t i_offset, type val)\
88 {\
89 if (!bo_extend(p_bo, i_offset + sizeof(type)))\
90 return false;\
91 handler(&p_bo->b->p_buffer[i_offset], val);\
92 return true;\
93 }
94
95 #define BO_ADD_DECL_S(func, handler, type) static inline bool func(bo_t *p_bo, type val)\
96 {\
97 if(!p_bo->b || !handler(p_bo, p_bo->b->i_buffer, val))\
98 return false;\
99 p_bo->b->i_buffer += sizeof(type);\
100 return true;\
101 }
102
103 #define BO_FUNC_DECL(suffix, handler, type ) \
104 BO_SET_DECL_S( bo_set_ ## suffix ## be, handler ## BE, type )\
105 BO_SET_DECL_S( bo_set_ ## suffix ## le, handler ## LE, type )\
106 BO_ADD_DECL_S( bo_add_ ## suffix ## be, bo_set_ ## suffix ## be, type )\
107 BO_ADD_DECL_S( bo_add_ ## suffix ## le, bo_set_ ## suffix ## le, type )
108
bo_set_8(bo_t * p_bo,size_t i_offset,uint8_t i)109 static inline bool bo_set_8(bo_t *p_bo, size_t i_offset, uint8_t i)
110 {
111 if (!bo_extend(p_bo, i_offset + 1))
112 return false;
113 p_bo->b->p_buffer[i_offset] = i;
114 return true;
115 }
116
bo_add_8(bo_t * p_bo,uint8_t i)117 static inline bool bo_add_8(bo_t *p_bo, uint8_t i)
118 {
119 if(!p_bo->b || !bo_set_8( p_bo, p_bo->b->i_buffer, i ))
120 return false;
121 p_bo->b->i_buffer++;
122 return true;
123 }
124
125 /* declares all bo_[set,add]_[16,32,64] */
126 BO_FUNC_DECL( 16, SetW, uint16_t )
127 BO_FUNC_DECL( 32, SetDW, uint32_t )
128 BO_FUNC_DECL( 64, SetQW, uint64_t )
129
130 #undef BO_FUNC_DECL
131 #undef BO_SET_DECL_S
132 #undef BO_ADD_DECL_S
133
bo_add_24be(bo_t * p_bo,uint32_t i)134 static inline bool bo_add_24be(bo_t *p_bo, uint32_t i)
135 {
136 if(!p_bo->b || !bo_extend(p_bo, p_bo->b->i_buffer + 3))
137 return false;
138 p_bo->b->p_buffer[p_bo->b->i_buffer++] = ((i >> 16) & 0xff);
139 p_bo->b->p_buffer[p_bo->b->i_buffer++] = ((i >> 8) & 0xff);
140 p_bo->b->p_buffer[p_bo->b->i_buffer++] = (i & 0xff);
141 return true;
142 }
143
bo_swap_32be(bo_t * p_bo,size_t i_pos,uint32_t i)144 static inline void bo_swap_32be (bo_t *p_bo, size_t i_pos, uint32_t i)
145 {
146 if (!p_bo->b || p_bo->b->i_buffer < i_pos + 4)
147 return;
148 p_bo->b->p_buffer[i_pos ] = (i >> 24)&0xff;
149 p_bo->b->p_buffer[i_pos + 1] = (i >> 16)&0xff;
150 p_bo->b->p_buffer[i_pos + 2] = (i >> 8)&0xff;
151 p_bo->b->p_buffer[i_pos + 3] = (i )&0xff;
152 }
153
bo_add_mem(bo_t * p_bo,size_t i_size,const void * p_mem)154 static inline bool bo_add_mem(bo_t *p_bo, size_t i_size, const void *p_mem)
155 {
156 if(!p_bo->b || !bo_extend(p_bo, p_bo->b->i_buffer + i_size))
157 return false;
158 memcpy(&p_bo->b->p_buffer[p_bo->b->i_buffer], p_mem, i_size);
159 p_bo->b->i_buffer += i_size;
160 return true;
161 }
162
163 #define bo_add_fourcc(p_bo, fcc) bo_add_mem(p_bo, 4, fcc)
164
165 #endif // VLC_BOXES_H
166