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Fix hex editor bulk multibyte reads 

The existing API was such that BulkPeekUint(Start: 20, EndInclusive: 39) would actually read from the address range [20, 100) instead of [20, 40).  That's completely broken.  The hex editor, the only consumer of the API, made the same exact mistake in reverse so the problem wasn't immediately apparent, but it was a giant land mine waiting to happen.  Fix them both.
This commit is contained in:
nattthebear 2020-05-30 11:12:31 -04:00
parent 377567e2ba
commit 3962049847
2 changed files with 50 additions and 65 deletions
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83
src/BizHawk.Client.EmuHawk/tools/HexEditor/HexEditor.cs
View File

@ -65,8 +65,6 @@ namespace BizHawk.Client.EmuHawk
private MemoryDomain _domain = new NullMemoryDomain();
private long _row;
private long _addr;
private string _findStr = "";
private bool _mouseIsDown;
private byte[] _rom;
@ -474,8 +472,8 @@ namespace BizHawk.Client.EmuHawk
for (var i = 0; i < _rowsVisible; i++)
{
_row = i + HexScrollBar.Value;
_addr = _row << 4;
long _row = i + HexScrollBar.Value;
long _addr = _row << 4;
if (_addr >= _domain.Size)
{
break;
@ -503,8 +501,8 @@ namespace BizHawk.Client.EmuHawk
var charValues = MakeValues(1);
for (var i = 0; i < _rowsVisible; i++)
{
_row = i + HexScrollBar.Value;
_addr = _row << 4;
long _row = i + HexScrollBar.Value;
long _addr = _row << 4;
if (_addr >= _domain.Size)
{
break;
@ -550,63 +548,46 @@ namespace BizHawk.Client.EmuHawk
private Dictionary<long, long> MakeValues(int dataSize)
{
var addresses = new List<long>();
long start = (long)HexScrollBar.Value << 4;
long end = (long)(HexScrollBar.Value + _rowsVisible) << 4;
for (var i = 0; i < _rowsVisible; i++)
{
_row = i + HexScrollBar.Value;
_addr = _row << 4;
if (_addr >= _domain.Size)
{
break;
}
end = Math.Min(end, _domain.Size);
end &= -(long)dataSize;
for (var j = 0; j < 16; j += dataSize)
{
if (_addr + j + dataSize <= _domain.Size)
{
var address = _addr + j;
addresses.Add(address);
}
}
}
var range = new MutableRange<long>(start, end - 1);
var dict = new Dictionary<long, long>();
var range = new MutableRange<long>(addresses[0], addresses[0] + addresses.Count - 1);
switch (dataSize)
{
default:
case 1:
{
var vals = new byte[addresses.Count];
_domain.BulkPeekByte(range, vals);
for (var i = 0; i < addresses.Count; i++)
{
dict.Add(addresses[i], vals[i]);
}
break;
}
var vals = new byte[end - start];
_domain.BulkPeekByte(range, vals);
int i = 0;
for (var addr = start; addr < end; addr += dataSize)
dict.Add(addr, vals[i++]);
break;
}
case 2:
{
var vals = new ushort[addresses.Count];
_domain.BulkPeekUshort(range, BigEndian, vals);
for (var i = 0; i < addresses.Count; i++)
{
dict.Add(addresses[i], vals[i]);
}
break;
}
{
var vals = new ushort[(end - start) >> 1];
_domain.BulkPeekUshort(range, BigEndian, vals);
int i = 0;
for (var addr = start; addr < end; addr += dataSize)
dict.Add(addr, vals[i++]);
break;
}
case 4:
{
var vals = new uint[addresses.Count];
_domain.BulkPeekUint(range, BigEndian, vals);
for (var i = 0; i < addresses.Count; i++)
{
dict.Add(addresses[i], vals[i]);
}
break;
}
{
var vals = new uint[(end - start) >> 2];
_domain.BulkPeekUint(range, BigEndian, vals);
int i = 0;
for (var addr = start; addr < end; addr += dataSize)
dict.Add(addr, vals[i++]);
break;
}
}
return dict;

32
src/BizHawk.Emulation.Common/Base Implementations/MemoryDomain.cs
View File

@ -125,18 +125,20 @@ namespace BizHawk.Emulation.Common
{
throw new ArgumentException();
}
var start = addresses.Start;
var end = addresses.EndInclusive + 1;
var nAddresses = (long) addresses.Count();
if (nAddresses != values.Length)
if ((start & 1) != 0 || (end & 1) != 0)
throw new InvalidOperationException("The API contract doesn't define what to do for unaligned reads and writes!");
if (values.LongLength * 2 != end - start)
{
// a longer array could be valid, but nothing needs that so don't support it for now
throw new InvalidOperationException("Invalid length of values array");
}
var start = addresses.Start;
for (var i = 0; i < nAddresses; i++)
{
values[i] = PeekUshort(start + i*2, bigEndian);
}
for (var i = 0; i < values.Length; i++, start += 2)
values[i] = PeekUshort(start, bigEndian);
}
public virtual void BulkPeekUint(Range<long> addresses, bool bigEndian, uint[] values)
@ -145,18 +147,20 @@ namespace BizHawk.Emulation.Common
{
throw new ArgumentException();
}
var start = addresses.Start;
var end = addresses.EndInclusive + 1;
var nAddresses = (long) addresses.Count();
if (nAddresses != values.Length)
if ((start & 3) != 0 || (end & 3) != 0)
throw new InvalidOperationException("The API contract doesn't define what to do for unaligned reads and writes!");
if (values.LongLength * 4 != end - start)
{
// a longer array could be valid, but nothing needs that so don't support it for now
throw new InvalidOperationException("Invalid length of values array");
}
var start = addresses.Start;
for (var i = 0; i<nAddresses; i++)
{
values[i] = PeekUint(start + i*4, bigEndian);
}
for (var i = 0; i < values.Length; i++, start += 4)
values[i] = PeekUshort(start, bigEndian);
}
}
}