1 /*
2  *  Copyright (c) 2010 The WebM project authors. All Rights Reserved.
3  *
4  *  Use of this source code is governed by a BSD-style license
5  *  that can be found in the LICENSE file in the root of the source
6  *  tree. An additional intellectual property rights grant can be found
7  *  in the file PATENTS.  All contributing project authors may
8  *  be found in the AUTHORS file in the root of the source tree.
9  */
10 #include "EbmlWriter.h"
11 #include <stdlib.h>
12 #include <wchar.h>
13 #include <string.h>
14 #include <limits.h>
15 #if defined(_MSC_VER)
16 #define LITERALU64(n) n
17 #else
18 #define LITERALU64(n) n##LLU
19 #endif
20 
Ebml_WriteLen(EbmlGlobal * glob,int64_t val)21 void Ebml_WriteLen(EbmlGlobal *glob, int64_t val) {
22   /* TODO check and make sure we are not > than 0x0100000000000000LLU */
23   unsigned char size = 8; /* size in bytes to output */
24 
25   /* mask to compare for byte size */
26   int64_t minVal = 0xff;
27 
28   for (size = 1; size < 8; size ++) {
29     if (val < minVal)
30       break;
31 
32     minVal = (minVal << 7);
33   }
34 
35   val |= (((uint64_t)0x80) << ((size - 1) * 7));
36 
37   Ebml_Serialize(glob, (void *) &val, sizeof(val), size);
38 }
39 
Ebml_WriteString(EbmlGlobal * glob,const char * str)40 void Ebml_WriteString(EbmlGlobal *glob, const char *str) {
41   const size_t size_ = strlen(str);
42   const uint64_t  size = size_;
43   Ebml_WriteLen(glob, size);
44   /* TODO: it's not clear from the spec whether the nul terminator
45    * should be serialized too.  For now we omit the null terminator.
46    */
47   Ebml_Write(glob, str, (unsigned long)size);
48 }
49 
Ebml_WriteUTF8(EbmlGlobal * glob,const wchar_t * wstr)50 void Ebml_WriteUTF8(EbmlGlobal *glob, const wchar_t *wstr) {
51   const size_t strlen = wcslen(wstr);
52 
53   /* TODO: it's not clear from the spec whether the nul terminator
54    * should be serialized too.  For now we include it.
55    */
56   const uint64_t  size = strlen;
57 
58   Ebml_WriteLen(glob, size);
59   Ebml_Write(glob, wstr, (unsigned long)size);
60 }
61 
Ebml_WriteID(EbmlGlobal * glob,unsigned long class_id)62 void Ebml_WriteID(EbmlGlobal *glob, unsigned long class_id) {
63   int len;
64 
65   if (class_id >= 0x01000000)
66     len = 4;
67   else if (class_id >= 0x00010000)
68     len = 3;
69   else if (class_id >= 0x00000100)
70     len = 2;
71   else
72     len = 1;
73 
74   Ebml_Serialize(glob, (void *)&class_id, sizeof(class_id), len);
75 }
76 
Ebml_SerializeUnsigned64(EbmlGlobal * glob,unsigned long class_id,uint64_t ui)77 void Ebml_SerializeUnsigned64(EbmlGlobal *glob, unsigned long class_id, uint64_t ui) {
78   unsigned char sizeSerialized = 8 | 0x80;
79   Ebml_WriteID(glob, class_id);
80   Ebml_Serialize(glob, &sizeSerialized, sizeof(sizeSerialized), 1);
81   Ebml_Serialize(glob, &ui, sizeof(ui), 8);
82 }
83 
Ebml_SerializeUnsigned(EbmlGlobal * glob,unsigned long class_id,unsigned long ui)84 void Ebml_SerializeUnsigned(EbmlGlobal *glob, unsigned long class_id, unsigned long ui) {
85   unsigned char size = 8; /* size in bytes to output */
86   unsigned char sizeSerialized = 0;
87   unsigned long minVal;
88 
89   Ebml_WriteID(glob, class_id);
90   minVal = 0x7fLU; /* mask to compare for byte size */
91 
92   for (size = 1; size < 4; size ++) {
93     if (ui < minVal) {
94       break;
95     }
96 
97     minVal <<= 7;
98   }
99 
100   sizeSerialized = 0x80 | size;
101   Ebml_Serialize(glob, &sizeSerialized, sizeof(sizeSerialized), 1);
102   Ebml_Serialize(glob, &ui, sizeof(ui), size);
103 }
104 /* TODO: perhaps this is a poor name for this id serializer helper function */
Ebml_SerializeBinary(EbmlGlobal * glob,unsigned long class_id,unsigned long bin)105 void Ebml_SerializeBinary(EbmlGlobal *glob, unsigned long class_id, unsigned long bin) {
106   int size;
107   for (size = 4; size > 1; size--) {
108     if (bin & (unsigned int)0x000000ff << ((size - 1) * 8))
109       break;
110   }
111   Ebml_WriteID(glob, class_id);
112   Ebml_WriteLen(glob, size);
113   Ebml_WriteID(glob, bin);
114 }
115 
Ebml_SerializeFloat(EbmlGlobal * glob,unsigned long class_id,double d)116 void Ebml_SerializeFloat(EbmlGlobal *glob, unsigned long class_id, double d) {
117   unsigned char len = 0x88;
118 
119   Ebml_WriteID(glob, class_id);
120   Ebml_Serialize(glob, &len, sizeof(len), 1);
121   Ebml_Serialize(glob,  &d, sizeof(d), 8);
122 }
123 
Ebml_WriteSigned16(EbmlGlobal * glob,short val)124 void Ebml_WriteSigned16(EbmlGlobal *glob, short val) {
125   signed long out = ((val & 0x003FFFFF) | 0x00200000) << 8;
126   Ebml_Serialize(glob, &out, sizeof(out), 3);
127 }
128 
Ebml_SerializeString(EbmlGlobal * glob,unsigned long class_id,const char * s)129 void Ebml_SerializeString(EbmlGlobal *glob, unsigned long class_id, const char *s) {
130   Ebml_WriteID(glob, class_id);
131   Ebml_WriteString(glob, s);
132 }
133 
Ebml_SerializeUTF8(EbmlGlobal * glob,unsigned long class_id,wchar_t * s)134 void Ebml_SerializeUTF8(EbmlGlobal *glob, unsigned long class_id, wchar_t *s) {
135   Ebml_WriteID(glob,  class_id);
136   Ebml_WriteUTF8(glob,  s);
137 }
138 
Ebml_SerializeData(EbmlGlobal * glob,unsigned long class_id,unsigned char * data,unsigned long data_length)139 void Ebml_SerializeData(EbmlGlobal *glob, unsigned long class_id, unsigned char *data, unsigned long data_length) {
140   Ebml_WriteID(glob, class_id);
141   Ebml_WriteLen(glob, data_length);
142   Ebml_Write(glob,  data, data_length);
143 }
144 
Ebml_WriteVoid(EbmlGlobal * glob,unsigned long vSize)145 void Ebml_WriteVoid(EbmlGlobal *glob, unsigned long vSize) {
146   unsigned char tmp = 0;
147   unsigned long i = 0;
148 
149   Ebml_WriteID(glob, 0xEC);
150   Ebml_WriteLen(glob, vSize);
151 
152   for (i = 0; i < vSize; i++) {
153     Ebml_Write(glob, &tmp, 1);
154   }
155 }
156 
157 /* TODO Serialize Date */
158