webm/mkvmuxerutil.cpp
Frank Galligan 000944c4e4 Fix bug with calculating master element sizes.
There was a potential bug with calculating the size of a master
element. The size was being calculated with a straight unsigned
integer when it should have been calculated with a coded
integer.

Change-Id: I68422ecdb7818af51ded2953a8914fcdc8858f7a
2012-01-25 10:28:26 -05:00

391 lines
7.9 KiB
C++

// Copyright (c) 2011 The WebM project authors. All Rights Reserved.
//
// Use of this source code is governed by a BSD-style license
// that can be found in the LICENSE file in the root of the source
// tree. An additional intellectual property rights grant can be found
// in the file PATENTS. All contributing project authors may
// be found in the AUTHORS file in the root of the source tree.
#include "mkvmuxerutil.hpp"
#include <math.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <new>
#include "mkvwriter.hpp"
#include "webmids.hpp"
namespace mkvmuxer {
int32 GetCodedUIntSize(uint64 value) {
if (value < 0x000000000000007FULL)
return 1;
else if (value < 0x0000000000003FFFULL)
return 2;
else if (value < 0x00000000001FFFFFULL)
return 3;
else if (value < 0x000000000FFFFFFFULL)
return 4;
else if (value < 0x00000007FFFFFFFFULL)
return 5;
else if (value < 0x000003FFFFFFFFFFULL)
return 6;
else if (value < 0x0001FFFFFFFFFFFFULL)
return 7;
return 8;
}
int32 GetUIntSize(uint64 value) {
if (value < 0x0000000000000100ULL)
return 1;
else if (value < 0x0000000000010000ULL)
return 2;
else if (value < 0x0000000001000000ULL)
return 3;
else if (value < 0x0000000100000000ULL)
return 4;
else if (value < 0x0000010000000000ULL)
return 5;
else if (value < 0x0001000000000000ULL)
return 6;
else if (value < 0x0100000000000000ULL)
return 7;
return 8;
}
uint64 EbmlMasterElementSize(uint64 type, uint64 value) {
// Size of EBML ID
int32 ebml_size = GetUIntSize(type);
// Datasize
ebml_size += GetCodedUIntSize(value);
return ebml_size;
}
uint64 EbmlElementSize(uint64 type, uint64 value) {
// Size of EBML ID
int32 ebml_size = GetUIntSize(type);
// Datasize
ebml_size += GetUIntSize(value);
// Size of Datasize
ebml_size++;
return ebml_size;
}
uint64 EbmlElementSize(uint64 type, float value) {
// Size of EBML ID
uint64 ebml_size = GetUIntSize(type);
// Datasize
ebml_size += sizeof(value);
// Size of Datasize
ebml_size++;
return ebml_size;
}
uint64 EbmlElementSize(uint64 type, const char* value) {
if (!value)
return 0;
// Size of EBML ID
uint64 ebml_size = GetUIntSize(type);
// Datasize
ebml_size += strlen(value);
// Size of Datasize
ebml_size++;
return ebml_size;
}
uint64 EbmlElementSize(uint64 type, const uint8* value, uint64 size) {
if (!value)
return 0;
// Size of EBML ID
uint64 ebml_size = GetUIntSize(type);
// Datasize
ebml_size += size;
// Size of Datasize
ebml_size += GetCodedUIntSize(size);
return ebml_size;
}
int32 SerializeInt(IMkvWriter* writer, int64 value, int32 size) {
if (!writer || size < 1 || size > 8)
return -1;
for (int32 i = 1; i <= size; ++i) {
const int32 byte_count = size - i;
const int32 bit_count = byte_count * 8;
const int64 bb = value >> bit_count;
const uint8 b = static_cast<uint8>(bb);
const int32 status = writer->Write(&b, 1);
if (status < 0)
return status;
}
return 0;
}
int32 SerializeFloat(IMkvWriter* writer, float f) {
if (!writer)
return -1;
const uint32& val = reinterpret_cast<const uint32&>(f);
for (int32 i = 1; i <= 4; ++i) {
const int32 byte_count = 4 - i;
const int32 bit_count = byte_count * 8;
const uint32 bb = val >> bit_count;
const uint8 b = static_cast<uint8>(bb);
const int32 status = writer->Write(&b, 1);
if (status < 0)
return status;
}
return 0;
}
int32 WriteUInt(IMkvWriter* writer, uint64 value) {
if (!writer)
return -1;
int32 size = GetCodedUIntSize(value);
return WriteUIntSize(writer, value, size);
}
int32 WriteUIntSize(IMkvWriter* writer, uint64 value, int32 size) {
if (!writer || size < 0 || size > 8)
return -1;
if (size > 0) {
const uint64 bit = 1LL << (size * 7);
if (value > (bit - 2))
return -1;
value |= bit;
} else {
size = 1;
int64 bit;
for (;;) {
bit = 1LL << (size * 7);
const uint64 max = bit - 2;
if (value <= max)
break;
++size;
}
if (size > 8)
return false;
value |= bit;
}
return SerializeInt(writer, value, size);
}
int32 WriteID(IMkvWriter* writer, uint64 type) {
if (!writer)
return -1;
writer->ElementStartNotify(type, writer->Position());
const int32 size = GetUIntSize(type);
return SerializeInt(writer, type, size);
}
bool WriteEbmlMasterElement(IMkvWriter* writer, uint64 type, uint64 size) {
if (!writer)
return false;
if (WriteID(writer, type))
return false;
if (WriteUInt(writer, size))
return false;
return true;
}
bool WriteEbmlElement(IMkvWriter* writer, uint64 type, uint64 value) {
if (!writer)
return false;
if (WriteID(writer, type))
return false;
const uint64 size = GetUIntSize(value);
if (WriteUInt(writer, size))
return false;
if (SerializeInt(writer, value, static_cast<int32>(size)))
return false;
return true;
}
bool WriteEbmlElement(IMkvWriter* writer, uint64 type, float value) {
if (!writer)
return false;
if (WriteID(writer, type))
return false;
if (WriteUInt(writer, 4))
return false;
if (SerializeFloat(writer, value))
return false;
return true;
}
bool WriteEbmlElement(IMkvWriter* writer, uint64 type, const char* value) {
if (!writer || !value)
return false;
if (WriteID(writer, type))
return false;
const int32 length = strlen(value);
if (WriteUInt(writer, length))
return false;
if (writer->Write(value, length))
return false;
return true;
}
bool WriteEbmlElement(IMkvWriter* writer,
uint64 type,
const uint8* value,
uint64 size) {
if (!writer || !value || size < 1)
return false;
if (WriteID(writer, type))
return false;
if (WriteUInt(writer, size))
return false;
if (writer->Write(value, static_cast<uint32>(size)))
return false;
return true;
}
uint64 WriteSimpleBlock(IMkvWriter* writer,
const uint8* data,
uint64 length,
char track_number,
short timecode,
bool is_key) {
if (!writer || !data || length < 1 || track_number < 1 || timecode < 0)
return false;
if (WriteID(writer, kMkvSimpleBlock))
return 0;
const int32 size = static_cast<int32>(length) + 4;
if (WriteUInt(writer, size))
return 0;
if (WriteUInt(writer, static_cast<uint64>(track_number)))
return 0;
if (SerializeInt(writer, static_cast<uint64>(timecode), 2))
return 0;
uint64 flags = 0;
if(is_key)
flags |= 0x80;
if (SerializeInt(writer, flags, 1))
return 0;
if (writer->Write(data, static_cast<uint32>(length)))
return 0;
const uint64 element_size =
GetUIntSize(kMkvSimpleBlock) + GetCodedUIntSize(size) + 4 + length;
return element_size;
}
uint64 WriteVoidElement(IMkvWriter* writer, uint64 size) {
if (!writer)
return false;
// Subtract one for the void ID and the coded size.
uint64 void_entry_size = size - 1 - GetCodedUIntSize(size-1);
uint64 void_size = EbmlMasterElementSize(kMkvVoid, void_entry_size) +
void_entry_size;
if (void_size != size)
return 0;
const int64 payload_position = writer->Position();
if (payload_position < 0)
return 0;
if (WriteID(writer, kMkvVoid))
return 0;
if (WriteUInt(writer, void_entry_size))
return 0;
const uint8 value = 0;
for (int32 i = 0; i < static_cast<int32>(void_entry_size); ++i) {
if (writer->Write(&value, 1))
return 0;
}
const int64 stop_position = writer->Position();
if (stop_position < 0 ||
stop_position - payload_position != static_cast<int64>(void_size))
return 0;
return void_size;
}
void GetVersion(int32& major, int32& minor, int32& build, int32& revision) {
major = 0;
minor = 0;
build = 0;
revision = 1;
}
} // namespace mkvmuxer