Emulator-Archive/ppsspp
1
0
Fork 0
mirror of https://github.com/hrydgard/ppsspp.git synced 2025-02-27 01:17:09 +00:00
Code Issues Actions 2 Packages Projects Releases Wiki Activity

Mpeg: Validate data more during demux.

Browse Source 
This also parses a bit earlier, not requiring a full 2048 bytes ahead at
all times.
This commit is contained in:
Unknown W. Brackets 2016-06-04 18:00:41 -07:00
parent 41f2999a2b
commit c8d0270bb4
2 changed files with 64 additions and 20 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

80
Core/HW/MpegDemux.cpp
View File

@ -1,4 +1,5 @@
#include "MpegDemux.h"
#include "Core/Reporting.h"
const int PACKET_START_CODE_MASK = 0xffffff00;
const int PACKET_START_CODE_PREFIX = 0x00000100;
@ -137,9 +138,8 @@ int MpegDemux::readPesHeader(PesHeader &pesHeader, int length, int startCode) {
return length;
}
int MpegDemux::demuxStream(bool bdemux, int startCode, int channel)
int MpegDemux::demuxStream(bool bdemux, int startCode, int length, int channel)
{
int length = read16();
if (bdemux) {
PesHeader pesHeader(channel);
length = readPesHeader(pesHeader, length, startCode);
@ -185,49 +185,91 @@ bool MpegDemux::skipPackHeader() {
return true;
}
void MpegDemux::demux(int audioChannel)
bool MpegDemux::demux(int audioChannel)
{
if (audioChannel >= 0)
m_audioChannel = audioChannel;
while (m_index < m_readSize)
bool looksValid = false;
bool needMore = false;
while (m_index < m_readSize && !needMore)
{
if (m_index + 2048 > m_readSize)
break;
// Search for start code
int startCode = 0xFF;
while ((startCode & PACKET_START_CODE_MASK) != PACKET_START_CODE_PREFIX && !isEOF()) {
startCode = (startCode << 8) | read8();
}
// Not enough data available yet.
if (m_readSize - m_index < 16) {
m_index -= 4;
break;
}
switch (startCode) {
case PACK_START_CODE:
skipPackHeader();
if (skipPackHeader()) {
looksValid = true;
}
break;
case SYSTEM_HEADER_START_CODE:
skip(read16());
break;
case PADDING_STREAM:
case PRIVATE_STREAM_2:
{
int length = read16();
skip(length);
case SYSTEM_HEADER_START_CODE: {
looksValid = true;
int length = read16();
if (m_readSize - m_index < length) {
m_index -= 4 + 2;
needMore = true;
break;
}
skip(length);
break;
}
case PADDING_STREAM:
case PRIVATE_STREAM_2: {
looksValid = true;
int length = read16();
if (m_readSize - m_index < length) {
m_index -= 4 + 2;
needMore = true;
break;
}
skip(length);
break;
}
case PRIVATE_STREAM_1: {
// Audio stream
m_audioChannel = demuxStream(true, startCode, m_audioChannel);
int length = read16();
// Check for PES header marker.
looksValid = (m_buf[m_index] & 0xC0) == 0x80;
if (m_readSize - m_index < length) {
m_index -= 4 + 2;
needMore = true;
break;
}
m_audioChannel = demuxStream(true, startCode, length, m_audioChannel);
looksValid = true;
break;
}
case 0x1E0: case 0x1E1: case 0x1E2: case 0x1E3:
case 0x1E4: case 0x1E5: case 0x1E6: case 0x1E7:
case 0x1E8: case 0x1E9: case 0x1EA: case 0x1EB:
case 0x1EC: case 0x1ED: case 0x1EE: case 0x1EF:
case 0x1EC: case 0x1ED: case 0x1EE: case 0x1EF: {
// Video Stream
demuxStream(false, startCode, -1);
int length = read16();
// Check for PES header marker.
looksValid = (m_buf[m_index] & 0xC0) == 0x80;
if (m_readSize - m_index < length) {
m_index -= 4 + 2;
needMore = true;
break;
}
demuxStream(false, startCode, length, -1);
break;
}
case USER_DATA_START_CODE:
// User data, probably same as queried by sceMpegGetUserdataAu.
// Not sure what exactly to do or how much to read.
// TODO: implement properly.
WARN_LOG_REPORT_ONCE(mpeguserdata, ME, "MPEG user data found");
looksValid = true;
break;
}
}
@ -240,6 +282,8 @@ void MpegDemux::demux(int audioChannel)
m_index = 0;
m_readSize = 0;
}
return looksValid;
}
static bool isHeader(u8* audioStream, int offset)

4
Core/HW/MpegDemux.h
View File

@ -15,7 +15,7 @@ public:
~MpegDemux();
bool addStreamData(const u8 *buf, int addSize);
void demux(int audioChannel);
bool demux(int audioChannel);
// return its framesize
int getNextAudioFrame(u8 **buf, int *headerCode1, int *headerCode2, s64 *pts = NULL);
@ -64,7 +64,7 @@ private:
}
}
int readPesHeader(PesHeader &pesHeader, int length, int startCode);
int demuxStream(bool bdemux, int startCode, int channel);
int demuxStream(bool bdemux, int startCode, int length, int channel);
bool skipPackHeader();
int m_index;