656 lines
13 KiB
C++
656 lines
13 KiB
C++
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/*
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* The contents of this file are subject to the Mozilla Public
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* License Version 1.1 (the "License"); you may not use this file
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* except in compliance with the License. You may obtain a copy of
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* the License at http://www.mozilla.org/MPL/
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*
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* Software distributed under the License is distributed on an "AS
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* IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
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* implied. See the License for the specific language governing
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* rights and limitations under the License.
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*
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* The Original Code is MPEG4IP.
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*
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* The Initial Developer of the Original Code is Cisco Systems Inc.
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* Portions created by Cisco Systems Inc. are
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* Copyright (C) Cisco Systems Inc. 2001. All Rights Reserved.
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*
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* Contributor(s):
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* Dave Mackie dmackie@cisco.com
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*/
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#include "mp4common.h"
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// MP4File low level IO support
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u_int64_t MP4File::GetPosition(FILE* pFile)
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{
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if (m_memoryBuffer == NULL) {
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if (pFile == NULL) {
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ASSERT(m_pFile);
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u_int64_t fpos;
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if (m_virtual_IO->GetPosition(m_pFile, &fpos) != 0) {
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throw new MP4Error("getting position via Virtual I/O", "MP4GetPosition");
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}
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return fpos;
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} else {
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fpos_t fpos;
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if (fgetpos(pFile, &fpos) < 0) {
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throw new MP4Error(errno, "MP4GetPosition");
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}
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uint64_t ret;
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FPOS_TO_VAR(fpos, uint64_t, ret);
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return ret;
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}
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} else {
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return m_memoryBufferPosition;
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}
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}
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void MP4File::SetPosition(u_int64_t pos, FILE* pFile)
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{
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if (m_memoryBuffer == NULL) {
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if (pFile == NULL) {
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ASSERT(m_pFile);
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if (m_virtual_IO->SetPosition(m_pFile, pos) != 0) {
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throw new MP4Error("setting position via Virtual I/O", "MP4SetPosition");
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}
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} else {
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fpos_t fpos;
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VAR_TO_FPOS(fpos, pos);
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if (fsetpos(pFile, &fpos) < 0) {
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throw new MP4Error(errno, "MP4SetPosition");
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}
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}
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} else {
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if (pos >= m_memoryBufferSize) {
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// abort();
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throw new MP4Error("position out of range", "MP4SetPosition");
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}
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m_memoryBufferPosition = pos;
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}
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}
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u_int64_t MP4File::GetSize()
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{
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if (m_mode == 'w') {
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// we're always positioned at the end of file in write mode
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// except for short intervals in ReadSample and FinishWrite routines
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// so we rely on the faster approach of GetPosition()
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// instead of flushing to disk, and then stat'ing the file
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m_fileSize = GetPosition();
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} // else read mode, fileSize was determined at Open()
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return m_fileSize;
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}
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void MP4File::ReadBytes(u_int8_t* pBytes, u_int32_t numBytes, FILE* pFile)
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{
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// handle degenerate cases
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if (numBytes == 0) {
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return;
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}
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ASSERT(pBytes);
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WARNING(m_numReadBits > 0);
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if (m_memoryBuffer == NULL) {
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if (pFile == NULL) {
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ASSERT(m_pFile);
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if (m_virtual_IO->Read(m_pFile, pBytes, numBytes) != numBytes) {
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throw new MP4Error("not enough bytes, reached end-of-file", "MP4ReadBytes");
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}
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} else {
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if (fread(pBytes, 1, numBytes, pFile) != numBytes) {
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if (feof(pFile)) {
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throw new MP4Error(
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"not enough bytes, reached end-of-file",
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"MP4ReadBytes");
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} else {
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throw new MP4Error(errno, "MP4ReadBytes");
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}
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}
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}
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} else {
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if (m_memoryBufferPosition + numBytes > m_memoryBufferSize) {
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throw new MP4Error(
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"not enough bytes, reached end-of-memory",
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"MP4ReadBytes");
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}
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memcpy(pBytes, &m_memoryBuffer[m_memoryBufferPosition], numBytes);
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m_memoryBufferPosition += numBytes;
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}
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return;
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}
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void MP4File::PeekBytes(u_int8_t* pBytes, u_int32_t numBytes, FILE* pFile)
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{
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u_int64_t pos = GetPosition(pFile);
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ReadBytes(pBytes, numBytes, pFile);
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SetPosition(pos, pFile);
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}
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void MP4File::EnableMemoryBuffer(u_int8_t* pBytes, u_int64_t numBytes)
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{
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ASSERT(m_memoryBuffer == NULL);
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if (pBytes) {
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m_memoryBuffer = pBytes;
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m_memoryBufferSize = numBytes;
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} else {
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if (numBytes) {
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m_memoryBufferSize = numBytes;
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} else {
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m_memoryBufferSize = 4096;
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}
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m_memoryBuffer = (u_int8_t*)MP4Malloc(m_memoryBufferSize);
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}
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m_memoryBufferPosition = 0;
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}
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void MP4File::DisableMemoryBuffer(u_int8_t** ppBytes, u_int64_t* pNumBytes)
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{
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ASSERT(m_memoryBuffer != NULL);
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if (ppBytes) {
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*ppBytes = m_memoryBuffer;
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}
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if (pNumBytes) {
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*pNumBytes = m_memoryBufferPosition;
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}
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m_memoryBuffer = NULL;
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m_memoryBufferSize = 0;
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m_memoryBufferPosition = 0;
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}
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void MP4File::WriteBytes(u_int8_t* pBytes, u_int32_t numBytes, FILE* pFile)
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{
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ASSERT(m_numWriteBits == 0 || m_numWriteBits >= 8);
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if (pBytes == NULL || numBytes == 0) {
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return;
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}
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if (m_memoryBuffer == NULL) {
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if (pFile == NULL) {
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ASSERT(m_pFile);
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if (m_virtual_IO->Write(m_pFile, pBytes, numBytes) != numBytes) {
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throw new MP4Error("error writing bytes via virtual I/O", "MP4WriteBytes");
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}
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} else {
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u_int32_t rc = (u_int32_t)fwrite(pBytes, 1, numBytes, pFile);
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if (rc != numBytes) {
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throw new MP4Error(errno, "MP4WriteBytes");
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}
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}
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} else {
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if (m_memoryBufferPosition + numBytes > m_memoryBufferSize) {
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m_memoryBufferSize = 2 * (m_memoryBufferSize + numBytes);
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m_memoryBuffer = (u_int8_t*)
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MP4Realloc(m_memoryBuffer, m_memoryBufferSize);
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}
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memcpy(&m_memoryBuffer[m_memoryBufferPosition], pBytes, numBytes);
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m_memoryBufferPosition += numBytes;
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}
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}
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u_int64_t MP4File::ReadUInt(u_int8_t size)
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{
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switch (size) {
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case 1:
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return ReadUInt8();
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case 2:
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return ReadUInt16();
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case 3:
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return ReadUInt24();
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case 4:
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return ReadUInt32();
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case 8:
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return ReadUInt64();
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default:
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ASSERT(false);
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return 0;
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}
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}
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void MP4File::WriteUInt(u_int64_t val, u_int8_t size)
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{
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switch (size) {
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case 1:
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WriteUInt8((u_int8_t)val);
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break;
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case 2:
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WriteUInt16((u_int16_t)val);
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break;
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case 3:
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WriteUInt24((u_int32_t)val);
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break;
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case 4:
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WriteUInt32((u_int32_t)val);
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break;
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case 8:
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WriteUInt64((u_int64_t)val);
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break;
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default:
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ASSERT(false);
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break;
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}
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}
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#if 0
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void MP4File::WriteUInt(u_int64_t value, u_int8_t size)
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{
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switch (size) {
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case 1:
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WriteUInt8(value);
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case 2:
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WriteUInt16(value);
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case 3:
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WriteUInt24(value);
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case 4:
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WriteUInt32(value);
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case 8:
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WriteUInt64(value);
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default:
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ASSERT(false);
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}
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}
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#endif
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u_int8_t MP4File::ReadUInt8()
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{
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u_int8_t data;
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ReadBytes(&data, 1);
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return data;
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}
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void MP4File::WriteUInt8(u_int8_t value)
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{
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WriteBytes(&value, 1);
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}
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u_int16_t MP4File::ReadUInt16()
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{
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u_int8_t data[2];
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ReadBytes(&data[0], 2);
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return ((data[0] << 8) | data[1]);
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}
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void MP4File::WriteUInt16(u_int16_t value)
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{
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u_int8_t data[2];
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data[0] = (value >> 8) & 0xFF;
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data[1] = value & 0xFF;
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WriteBytes(data, 2);
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}
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u_int32_t MP4File::ReadUInt24()
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{
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u_int8_t data[3];
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ReadBytes(&data[0], 3);
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return ((data[0] << 16) | (data[1] << 8) | data[2]);
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}
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void MP4File::WriteUInt24(u_int32_t value)
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{
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u_int8_t data[3];
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data[0] = (value >> 16) & 0xFF;
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data[1] = (value >> 8) & 0xFF;
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data[2] = value & 0xFF;
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WriteBytes(data, 3);
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}
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u_int32_t MP4File::ReadUInt32()
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{
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u_int8_t data[4];
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ReadBytes(&data[0], 4);
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return ((data[0] << 24) | (data[1] << 16) | (data[2] << 8) | data[3]);
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}
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void MP4File::WriteUInt32(u_int32_t value)
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{
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u_int8_t data[4];
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data[0] = (value >> 24) & 0xFF;
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data[1] = (value >> 16) & 0xFF;
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data[2] = (value >> 8) & 0xFF;
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data[3] = value & 0xFF;
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WriteBytes(data, 4);
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}
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u_int64_t MP4File::ReadUInt64()
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{
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u_int8_t data[8];
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u_int64_t result = 0;
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u_int64_t temp;
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ReadBytes(&data[0], 8);
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for (int i = 0; i < 8; i++) {
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temp = data[i];
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result |= temp << ((7 - i) * 8);
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}
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return result;
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}
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void MP4File::WriteUInt64(u_int64_t value)
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{
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u_int8_t data[8];
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for (int i = 7; i >= 0; i--) {
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data[i] = value & 0xFF;
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value >>= 8;
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}
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WriteBytes(data, 8);
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}
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float MP4File::ReadFixed16()
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{
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u_int8_t iPart = ReadUInt8();
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u_int8_t fPart = ReadUInt8();
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return iPart + (((float)fPart) / 0x100);
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}
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void MP4File::WriteFixed16(float value)
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{
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if (value >= 0x100) {
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throw new MP4Error(ERANGE, "MP4WriteFixed16");
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}
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u_int8_t iPart = (u_int8_t)value;
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u_int8_t fPart = (u_int8_t)((value - iPart) * 0x100);
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WriteUInt8(iPart);
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WriteUInt8(fPart);
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}
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float MP4File::ReadFixed32()
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{
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u_int16_t iPart = ReadUInt16();
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u_int16_t fPart = ReadUInt16();
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return iPart + (((float)fPart) / 0x10000);
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}
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void MP4File::WriteFixed32(float value)
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{
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if (value >= 0x10000) {
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throw new MP4Error(ERANGE, "MP4WriteFixed32");
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}
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u_int16_t iPart = (u_int16_t)value;
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u_int16_t fPart = (u_int16_t)((value - iPart) * 0x10000);
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WriteUInt16(iPart);
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WriteUInt16(fPart);
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}
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float MP4File::ReadFloat()
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{
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union {
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float f;
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u_int32_t i;
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} u;
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u.i = ReadUInt32();
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return u.f;
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}
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void MP4File::WriteFloat(float value)
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{
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union {
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float f;
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u_int32_t i;
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} u;
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u.f = value;
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WriteUInt32(u.i);
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}
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char* MP4File::ReadString()
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{
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uint32_t readSize=1;
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u_int32_t length = 0;
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u_int32_t alloced = 64;
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uint8_t* data = (uint8_t*)MP4Malloc(alloced);
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ReadBytes((u_int8_t*)&data[length++], 1);
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if (data[0] == 0xFF || data[0] == 0xFE)
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{
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ReadBytes((u_int8_t*)&data[length++], 1);
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if ((data[0] == 0xFF && data[1] == 0xFE)
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|| (data[0] == 0xFE && data[1] == 0xFF))
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readSize=2; // Unicode
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}
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while (1)
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{
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if (readSize == 1 && data[length - 1] == 0)
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break;
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if (readSize == 2)
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{
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uint16_t *utf16 = (uint16_t *)data;
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if (utf16[length/2 - 1] == 0)
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break;
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}
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if (length == alloced) {
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data = (uint8_t*)MP4Realloc(data, alloced * 2);
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if (data == NULL) return NULL;
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alloced *= 2;
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}
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ReadBytes((u_int8_t*)&data[length], readSize);
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length+=readSize;
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}
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data = (uint8_t*)MP4Realloc(data, length);
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return (char *)data;
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}
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uint16_t *MP4File::ReadUnicodeString()
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{
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u_int32_t length = 0;
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u_int32_t alloced = 64;
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uint16_t *data = (uint16_t *)MP4Malloc(alloced*sizeof(uint16_t));
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do {
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|
if (length == alloced) {
|
||
|
data = (uint16_t *)MP4Realloc(data, (alloced * 2)*sizeof(uint16_t));
|
||
|
if (data == NULL) return NULL;
|
||
|
alloced *= 2;
|
||
|
}
|
||
|
ReadBytes((u_int8_t *)&data[length], 2);
|
||
|
length++;
|
||
|
} while (data[length - 1] != 0);
|
||
|
|
||
|
data = (uint16_t *)MP4Realloc(data, length*sizeof(uint16_t));
|
||
|
return data;
|
||
|
}
|
||
|
|
||
|
void MP4File::WriteString(char* string)
|
||
|
{
|
||
|
if (string == NULL) {
|
||
|
u_int8_t zero = 0;
|
||
|
WriteBytes(&zero, 1);
|
||
|
} else {
|
||
|
WriteBytes((u_int8_t*)string, (u_int32_t)strlen(string) + 1);
|
||
|
}
|
||
|
}
|
||
|
|
||
|
void MP4File::WriteUnicodeString(const uint16_t *string)
|
||
|
{
|
||
|
if (string == NULL) {
|
||
|
u_int8_t zero = 0;
|
||
|
WriteBytes(&zero, 1);
|
||
|
} else {
|
||
|
const uint16_t *itr = string;
|
||
|
int len=0;
|
||
|
while (*itr)
|
||
|
{
|
||
|
itr++;
|
||
|
len++;
|
||
|
}
|
||
|
WriteBytes((u_int8_t*)string, (len + 1)*sizeof(uint16_t));
|
||
|
}
|
||
|
}
|
||
|
|
||
|
char* MP4File::ReadCountedString(u_int8_t charSize, bool allowExpandedCount)
|
||
|
{
|
||
|
u_int32_t charLength;
|
||
|
if (allowExpandedCount) {
|
||
|
u_int8_t b;
|
||
|
uint ix = 0;
|
||
|
charLength = 0;
|
||
|
do {
|
||
|
b = ReadUInt8();
|
||
|
charLength += b;
|
||
|
ix++;
|
||
|
if (ix > 25)
|
||
|
throw new MP4Error(ERANGE,
|
||
|
"Counted string too long 25 * 255");
|
||
|
} while (b == 255);
|
||
|
} else {
|
||
|
charLength = ReadUInt8();
|
||
|
}
|
||
|
|
||
|
u_int32_t byteLength = charLength * charSize;
|
||
|
char* data = (char*)MP4Malloc(byteLength + 1);
|
||
|
if (byteLength > 0) {
|
||
|
ReadBytes((u_int8_t*)data, byteLength);
|
||
|
}
|
||
|
data[byteLength] = '\0';
|
||
|
return data;
|
||
|
}
|
||
|
|
||
|
void MP4File::WriteCountedString(char* string,
|
||
|
u_int8_t charSize, bool allowExpandedCount)
|
||
|
{
|
||
|
u_int32_t byteLength;
|
||
|
if (string) {
|
||
|
byteLength = (u_int32_t)strlen(string);
|
||
|
} else {
|
||
|
byteLength = 0;
|
||
|
}
|
||
|
u_int32_t charLength = byteLength / charSize;
|
||
|
|
||
|
if (allowExpandedCount) {
|
||
|
while (charLength >= 0xFF) {
|
||
|
WriteUInt8(0xFF);
|
||
|
charLength -= 0xFF;
|
||
|
}
|
||
|
WriteUInt8(charLength);
|
||
|
} else {
|
||
|
if (charLength > 255) {
|
||
|
throw new MP4Error(ERANGE, "Length is %d", "MP4WriteCountedString", charLength);
|
||
|
}
|
||
|
WriteUInt8(charLength);
|
||
|
}
|
||
|
|
||
|
if (byteLength > 0) {
|
||
|
WriteBytes((u_int8_t*)string, byteLength);
|
||
|
}
|
||
|
}
|
||
|
|
||
|
u_int64_t MP4File::ReadBits(u_int8_t numBits)
|
||
|
{
|
||
|
ASSERT(numBits > 0);
|
||
|
ASSERT(numBits <= 64);
|
||
|
|
||
|
u_int64_t bits = 0;
|
||
|
|
||
|
for (u_int8_t i = numBits; i > 0; i--) {
|
||
|
if (m_numReadBits == 0) {
|
||
|
ReadBytes(&m_bufReadBits, 1);
|
||
|
m_numReadBits = 8;
|
||
|
}
|
||
|
bits = (bits << 1) | ((m_bufReadBits >> (--m_numReadBits)) & 1);
|
||
|
}
|
||
|
|
||
|
return bits;
|
||
|
}
|
||
|
|
||
|
void MP4File::FlushReadBits()
|
||
|
{
|
||
|
// eat any remaining bits in the read buffer
|
||
|
m_numReadBits = 0;
|
||
|
}
|
||
|
|
||
|
void MP4File::WriteBits(u_int64_t bits, u_int8_t numBits)
|
||
|
{
|
||
|
ASSERT(numBits <= 64);
|
||
|
|
||
|
for (u_int8_t i = numBits; i > 0; i--) {
|
||
|
m_bufWriteBits |=
|
||
|
(((bits >> (i - 1)) & 1) << (8 - ++m_numWriteBits));
|
||
|
|
||
|
if (m_numWriteBits == 8) {
|
||
|
FlushWriteBits();
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
|
||
|
void MP4File::PadWriteBits(u_int8_t pad)
|
||
|
{
|
||
|
if (m_numWriteBits) {
|
||
|
WriteBits(pad ? 0xFF : 0x00, 8 - m_numWriteBits);
|
||
|
}
|
||
|
}
|
||
|
|
||
|
void MP4File::FlushWriteBits()
|
||
|
{
|
||
|
if (m_numWriteBits > 0) {
|
||
|
WriteBytes(&m_bufWriteBits, 1);
|
||
|
m_numWriteBits = 0;
|
||
|
m_bufWriteBits = 0;
|
||
|
}
|
||
|
}
|
||
|
|
||
|
u_int32_t MP4File::ReadMpegLength()
|
||
|
{
|
||
|
u_int32_t length = 0;
|
||
|
u_int8_t numBytes = 0;
|
||
|
u_int8_t b;
|
||
|
|
||
|
do {
|
||
|
b = ReadUInt8();
|
||
|
length = (length << 7) | (b & 0x7F);
|
||
|
numBytes++;
|
||
|
} while ((b & 0x80) && numBytes < 4);
|
||
|
|
||
|
return length;
|
||
|
}
|
||
|
|
||
|
void MP4File::WriteMpegLength(u_int32_t value, bool compact)
|
||
|
{
|
||
|
if (value > 0x0FFFFFFF) {
|
||
|
throw new MP4Error(ERANGE, "MP4WriteMpegLength");
|
||
|
}
|
||
|
|
||
|
int8_t numBytes;
|
||
|
|
||
|
if (compact) {
|
||
|
if (value <= 0x7F) {
|
||
|
numBytes = 1;
|
||
|
} else if (value <= 0x3FFF) {
|
||
|
numBytes = 2;
|
||
|
} else if (value <= 0x1FFFFF) {
|
||
|
numBytes = 3;
|
||
|
} else {
|
||
|
numBytes = 4;
|
||
|
}
|
||
|
} else {
|
||
|
numBytes = 4;
|
||
|
}
|
||
|
|
||
|
int8_t i = numBytes;
|
||
|
do {
|
||
|
i--;
|
||
|
u_int8_t b = (value >> (i * 7)) & 0x7F;
|
||
|
if (i > 0) {
|
||
|
b |= 0x80;
|
||
|
}
|
||
|
WriteUInt8(b);
|
||
|
} while (i > 0);
|
||
|
}
|