C++ (Cpp) MP4Descriptor::Read Examples

Example #1

File: mp4property.cpp Project: BOTCrusher/sagetv

void MP4DescriptorProperty::Read(MP4File* pFile, u_int32_t index)
{
	ASSERT(index == 0);

	if (m_implicit) {
		return;
	}

	u_int64_t start = pFile->GetPosition();

	while (true) {
		// enforce size limitation
		if (m_sizeLimit && pFile->GetPosition() >= start + m_sizeLimit) {
			break;
		}

		u_int8_t tag;
		try {
			pFile->PeekBytes(&tag, 1);
		}
		catch (MP4Error* e) {
			if (pFile->GetPosition() >= pFile->GetSize()) {
				// EOF
				delete e;
				break;
			}
			throw e;
		}

		// check if tag is in desired range
		if (tag < m_tagsStart || tag > m_tagsEnd) {
			break;
		}

		MP4Descriptor* pDescriptor = 
			AddDescriptor(tag);

		pDescriptor->Read(pFile);
	}

	// warnings
	if (m_mandatory && m_pDescriptors.Size() == 0) {
		VERBOSE_READ(pFile->GetVerbosity(),
			printf("Warning: Mandatory descriptor 0x%02x missing\n",
				m_tagsStart));
	} else if (m_onlyOne && m_pDescriptors.Size() > 1) {
		VERBOSE_READ(pFile->GetVerbosity(),
			printf("Warning: Descriptor 0x%02x has more than one instance\n",
				m_tagsStart));
	}
}