libmkv/EbmlWriter.c

   1 // Copyright (c) 2010 The WebM project authors. All Rights Reserved.
   2 //
   3 // Use of this source code is governed by a BSD-style license
   4 // that can be found in the LICENSE file in the root of the source
   5 // tree. An additional intellectual property rights grant can be found
   6 // in the file PATENTS.  All contributing project authors may
   7 // be found in the AUTHORS file in the root of the source tree.
   8
   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
  21 void Ebml_WriteLen(EbmlGlobal *glob, long long val)
  22 {
  23     //TODO check and make sure we are not > than 0x0100000000000000LLU
  24     unsigned char size = 8; //size in bytes to output
  25     unsigned long long minVal = LITERALU64(0x00000000000000ff); //mask to compare for byte size
  26
  27     for (size = 1; size < 8; size ++)
  28     {
  29         if (val < minVal)
  30             break;
  31
  32         minVal = (minVal << 7);
  33     }
  34
  35     val |= (LITERALU64(0x000000000000080) << ((size - 1) * 7));
  36
  37     Ebml_Serialize(glob, (void *) &val, sizeof(val), size);
  38 }
  39
  40 void Ebml_WriteString(EbmlGlobal *glob, const char *str)
  41 {
  42     const size_t size_ = strlen(str);
  43     const unsigned long long  size = size_;
  44     Ebml_WriteLen(glob, size);
  45     //TODO: it's not clear from the spec whether the nul terminator
  46     //should be serialized too.  For now we omit the null terminator.
  47     Ebml_Write(glob, str, size);
  48 }
  49
  50 void Ebml_WriteUTF8(EbmlGlobal *glob, const wchar_t *wstr)
  51 {
  52     const size_t strlen = wcslen(wstr);
  53
  54     //TODO: it's not clear from the spec whether the nul terminator
  55     //should be serialized too.  For now we include it.
  56     const unsigned long long  size = strlen;
  57
  58     Ebml_WriteLen(glob, size);
  59     Ebml_Write(glob, wstr, size);
  60 }
  61
  62 void Ebml_WriteID(EbmlGlobal *glob, unsigned long class_id)
  63 {
  64     int len;
  65
  66     if (class_id >= 0x01000000)
  67         len = 4;
  68     else if (class_id >= 0x00010000)
  69         len = 3;
  70     else if (class_id >= 0x00000100)
  71         len = 2;
  72     else
  73         len = 1;
  74
  75     Ebml_Serialize(glob, (void *)&class_id, sizeof(class_id), len);
  76 }
  77
  78 void Ebml_SerializeUnsigned64(EbmlGlobal *glob, unsigned long class_id, uint64_t ui)
  79 {
  80     unsigned char sizeSerialized = 8 | 0x80;
  81     Ebml_WriteID(glob, class_id);
  82     Ebml_Serialize(glob, &sizeSerialized, sizeof(sizeSerialized), 1);
  83     Ebml_Serialize(glob, &ui, sizeof(ui), 8);
  84 }
  85
  86 void Ebml_SerializeUnsigned(EbmlGlobal *glob, unsigned long class_id, unsigned long ui)
  87 {
  88     unsigned char size = 8; //size in bytes to output
  89     unsigned char sizeSerialized = 0;
  90     unsigned long minVal;
  91
  92     Ebml_WriteID(glob, class_id);
  93     minVal = 0x7fLU; //mask to compare for byte size
  94
  95     for (size = 1; size < 4; size ++)
  96     {
  97         if (ui < minVal)
  98         {
  99             break;
 100         }
 101
 102         minVal <<= 7;
 103     }
 104
 105     sizeSerialized = 0x80 | size;
 106     Ebml_Serialize(glob, &sizeSerialized, sizeof(sizeSerialized), 1);
 107     Ebml_Serialize(glob, &ui, sizeof(ui), size);
 108 }
 109 //TODO: perhaps this is a poor name for this id serializer helper function
 110 void Ebml_SerializeBinary(EbmlGlobal *glob, unsigned long class_id, unsigned long bin)
 111 {
 112     int size;
 113     for (size=4; size > 1; size--)
 114     {
 115         if (bin & 0x000000ff << ((size-1) * 8))
 116             break;
 117     }
 118     Ebml_WriteID(glob, class_id);
 119     Ebml_WriteLen(glob, size);
 120     Ebml_WriteID(glob, bin);
 121 }
 122
 123 void Ebml_SerializeFloat(EbmlGlobal *glob, unsigned long class_id, double d)
 124 {
 125     unsigned char len = 0x88;
 126
 127     Ebml_WriteID(glob, class_id);
 128     Ebml_Serialize(glob, &len, sizeof(len), 1);
 129     Ebml_Serialize(glob,  &d, sizeof(d), 8);
 130 }
 131
 132 void Ebml_WriteSigned16(EbmlGlobal *glob, short val)
 133 {
 134     signed long out = ((val & 0x003FFFFF) | 0x00200000) << 8;
 135     Ebml_Serialize(glob, &out, sizeof(out), 3);
 136 }
 137
 138 void Ebml_SerializeString(EbmlGlobal *glob, unsigned long class_id, const char *s)
 139 {
 140     Ebml_WriteID(glob, class_id);
 141     Ebml_WriteString(glob, s);
 142 }
 143
 144 void Ebml_SerializeUTF8(EbmlGlobal *glob, unsigned long class_id, wchar_t *s)
 145 {
 146     Ebml_WriteID(glob,  class_id);
 147     Ebml_WriteUTF8(glob,  s);
 148 }
 149
 150 void Ebml_SerializeData(EbmlGlobal *glob, unsigned long class_id, unsigned char *data, unsigned long data_length)
 151 {
 152     Ebml_WriteID(glob, class_id);
 153     Ebml_WriteLen(glob, data_length);
 154     Ebml_Write(glob,  data, data_length);
 155 }
 156
 157 void Ebml_WriteVoid(EbmlGlobal *glob, unsigned long vSize)
 158 {
 159     unsigned char tmp = 0;
 160     unsigned long i = 0;
 161
 162     Ebml_WriteID(glob, 0xEC);
 163     Ebml_WriteLen(glob, vSize);
 164
 165     for (i = 0; i < vSize; i++)
 166     {
 167         Ebml_Write(glob, &tmp, 1);
 168     }
 169 }
 170
 171 //TODO Serialize Date