Skip to content

Commit

Permalink
Assign name to EnumType_1E, identify IEEE754
Browse files Browse the repository at this point in the history 
#37
  • Loading branch information
@jglim
jglim committed Sep 6, 2021
1 parent 27369e9 commit 0863049
Show file tree
Hide file tree
Showing 4 changed files with 81 additions and 33 deletions.
23 changes: 23 additions & 0 deletions Caesar/Caesar/BitUtility.cs
View file
Original file line number Diff line number Diff line change
@@ -1,4 +1,5 @@
using System;
using System.Runtime.InteropServices;
using System.Text;

namespace Caesar
Expand Down Expand Up @@ -80,6 +81,28 @@ public static byte[] PadBytes(byte[] inData, int finalSize)
return result;
}

[StructLayout(LayoutKind.Explicit)]
struct UIntFloat
{
[FieldOffset(0)]
public float FloatValue;

[FieldOffset(0)]
public uint IntValue;
}

/// <summary>
/// Directly converts an in-memory representation of an uint to a float.
/// </summary>
/// <param name="value"></param>
/// <returns></returns>
public static float ToFloat(uint value)
{
UIntFloat intermediate = new UIntFloat();
intermediate.IntValue = value;
return intermediate.FloatValue;
}


// Caesar specific

Expand Down
65 changes: 44 additions & 21 deletions Caesar/Caesar/DiagPresentation.cs
View file
Original file line number Diff line number Diff line change
Expand Up @@ -35,10 +35,10 @@ public class DiagPresentation
public int Unk18;
public int Unk19;
public int TypeLength_1A;
public int Unk1b;
public int InternalDataType; // discovered by @prj : #37
public int Type_1C;
public int Unk1d;
public int EnumType_1E;
public int SignBit; // discovered by @prj : #37
public int Unk1F;
public int Unk20;

Expand Down Expand Up @@ -126,11 +126,11 @@ public DiagPresentation(BinaryReader reader, long baseAddress, int presentations

Unk19 = CaesarReader.ReadBitflagInt32(ref bitflags, reader, -1);
TypeLength_1A = CaesarReader.ReadBitflagInt32(ref bitflags, reader, -1);
Unk1b = CaesarReader.ReadBitflagInt8(ref bitflags, reader, -1);
InternalDataType = CaesarReader.ReadBitflagInt8(ref bitflags, reader, -1);
Type_1C = CaesarReader.ReadBitflagInt8(ref bitflags, reader, -1);

Unk1d = CaesarReader.ReadBitflagInt8(ref bitflags, reader);
EnumType_1E = CaesarReader.ReadBitflagInt8(ref bitflags, reader);
SignBit = CaesarReader.ReadBitflagInt8(ref bitflags, reader);
Unk1F = CaesarReader.ReadBitflagInt8(ref bitflags, reader);
Unk20 = CaesarReader.ReadBitflagInt32(ref bitflags, reader);

Expand Down Expand Up @@ -169,7 +169,7 @@ public string InterpretData(byte[] inBytes, DiagPreparation inPreparation, bool
string descriptionPrefix = describe ? $"{DescriptionString}: " : "";
byte[] workingBytes = inBytes.Skip(inPreparation.BitPosition / 8).Take(TypeLength_1A).ToArray();

bool isEnumType = (EnumType_1E == 0) && ((Type_1C == 1) || (ScaleCountMaybe > 1));
bool isEnumType = (SignBit == 0) && ((Type_1C == 1) || (ScaleCountMaybe > 1));

// hack: sometimes hybrid types (regularly parsed as an scaled value if within bounds) are misinterpreted as pure enums
// this is a temporary fix for kilometerstand until there's a better way to ascertain its type
Expand Down Expand Up @@ -212,11 +212,10 @@ public string InterpretData(byte[] inBytes, DiagPreparation inPreparation, bool

string humanReadableType = $"UnhandledType:{dataType}";
string parsedValue = BitUtility.BytesToHex(workingBytes, true);
if ((dataType == 6 || (dataType == 20)))
if (dataType == 20)
{
// parse as a regular int (BE)

for (int i = 0; i < workingBytes.Length; i++)
for (int i = 0; i < workingBytes.Length; i++)
{
rawIntInterpretation <<= 8;
rawIntInterpretation |= workingBytes[i];
Expand All @@ -225,7 +224,7 @@ public string InterpretData(byte[] inBytes, DiagPreparation inPreparation, bool
humanReadableType = "IntegerType";

parsedValue = rawIntInterpretation.ToString();
if (dataType == 20)
if (dataType == 20)
{
humanReadableType = "ScaledType";

Expand All @@ -242,6 +241,31 @@ public string InterpretData(byte[] inBytes, DiagPreparation inPreparation, bool
parsedValue = valueToScale.ToString("0.000000");
}
}
else if (dataType == 6)
{
// type 6 refers to either internal presentation types 8 (ieee754 float) or 5 (unsigned int?)
// these values are tagged with an exclamation [!] i (jglim) am not sure if they will work correctly yet
// specifically, i am not sure if the big endian float parsing is done correctly
uint rawUIntInterpretation = 0;
for (int i = 0; i < 4; i++)
{
rawUIntInterpretation <<= 8;
rawUIntInterpretation |= workingBytes[i];
}

if (InternalDataType == 8)
{
// interpret as big-endian float, https://github.com/jglim/CaesarSuite/issues/37
parsedValue = BitUtility.ToFloat(rawUIntInterpretation).ToString("");
humanReadableType = "Float [!]";
}
else if (InternalDataType == 5)
{
// haven't seen this one around, will parse as a regular int (BE) for now
humanReadableType = "UnsignedIntegerType [!]";
parsedValue = rawUIntInterpretation.ToString();
}
}
else if (dataType == 18)
{
humanReadableType = "HexdumpType";
Expand Down Expand Up @@ -315,7 +339,6 @@ public string InterpretData(byte[] inBytes, DiagPreparation inPreparation, bool
public int GetDataType()
{
// see DIDiagServiceRealPresType

int result = -1;
if (Unk14 != -1)
{
Expand Down Expand Up @@ -346,21 +369,21 @@ public int GetDataType()
{
return 18; // hexdump raw
}
if (Unk1b != -1)
if (InternalDataType != -1)
{
if (Unk1b == 6)
if (InternalDataType == 6)
{
return 17; // ascii dump
}
else if (Unk1b == 7)
else if (InternalDataType == 7)
{
return 22; // ?? haven't seen this one around
}
else if (Unk1b == 8)
else if (InternalDataType == 8)
{
result = 6; // integer
result = 6; // IEEE754 float, discovered by @prj in https://github.com/jglim/CaesarSuite/issues/37
}
else if (Unk1b == 5)
else if (InternalDataType == 5)
{
// UNSIGNED integer (i haven't seen a const for uint around, sticking it into a regular int for now)
// this will be an issue for 32-bit+ uints
Expand All @@ -375,7 +398,7 @@ public int GetDataType()
Console.WriteLine("typelength and type must be valid");
// might be good to throw an exception here
}
if ((EnumType_1E == 1) || (EnumType_1E == 2))
if ((SignBit == 1) || (SignBit == 2))
{
result = 5; // ?? haven't seen this one around
}
Expand Down Expand Up @@ -424,10 +447,10 @@ public void PrintDebug()
Console.WriteLine($"{nameof(Unk18)}: {Unk18}");

Console.WriteLine($"{nameof(Unk19)}: {Unk19}");
Console.WriteLine($"{nameof(Unk1b)}: {Unk1b}");
Console.WriteLine($"{nameof(InternalDataType)}: {InternalDataType}");

Console.WriteLine($"{nameof(Unk1d)}: {Unk1d}");
Console.WriteLine($"{nameof(EnumType_1E)}: {EnumType_1E}");
Console.WriteLine($"{nameof(SignBit)}: {SignBit}");
Console.WriteLine($"{nameof(Unk1F)}: {Unk1F}");
Console.WriteLine($"{nameof(Unk20)}: {Unk20}");

Expand Down Expand Up @@ -481,9 +504,9 @@ public string CopyMinDebug()
sb.Append($" {nameof(Unk17)}: {Unk17}");
sb.Append($" {nameof(Unk18)}: {Unk18}");
sb.Append($" {nameof(Unk19)}: {Unk19}");
sb.Append($" {nameof(Unk1b)}: {Unk1b}");
sb.Append($" {nameof(InternalDataType)}: {InternalDataType}");
sb.Append($" {nameof(Unk1d)}: {Unk1d}");
sb.Append($" {nameof(EnumType_1E)}: {EnumType_1E}");
sb.Append($" {nameof(SignBit)}: {SignBit}");
sb.Append($" {nameof(Unk1F)}: {Unk1F}");
sb.Append($" {nameof(Unk20)}: {Unk20}");
sb.Append($" {nameof(TypeLengthBytesMaybe_21)}: {TypeLengthBytesMaybe_21}");
Expand Down
13 changes: 9 additions & 4 deletions Caesar/Diogenes/Forms/AboutForm.Designer.cs
View file

Some generated files are not rendered by default. Learn more about how customized files appear on GitHub.

13 changes: 5 additions & 8 deletions Caesar/Diogenes/Forms/MainForm.cs
View file
Original file line number Diff line number Diff line change
Expand Up @@ -1130,16 +1130,13 @@ private void genericDebugToolStripMenuItem_Click(object sender, EventArgs e)
{
foreach (ECU ecu in container.CaesarECUs)
{
foreach (DTC dtc in ecu.GlobalDTCs)
foreach (DiagPresentation pres in ecu.GlobalPresentations)
{
byte[] dtcQualBytes = BitUtility.BytesFromHex(dtc.Qualifier.Substring(1));
int dtcInt = (dtcQualBytes[0] << 16) | (dtcQualBytes[1] << 8) | dtcQualBytes[2];
long remainder = dtcInt & 0xFFC00000;
if (remainder > 0)
Console.WriteLine($"Pres : {pres.Qualifier} : {pres.GetDataType()}");
if (pres.InternalDataType == 8)
{
throw new NotImplementedException("fail");
throw new NotImplementedException("found a iee754 float!");
}
Console.WriteLine($"Q: {dtc.Qualifier} {dtcInt:X8} : {dtc.Description}");
}
}
}
Expand Down Expand Up @@ -1168,7 +1165,7 @@ private void genericDebugToolStripMenuItem_Click(object sender, EventArgs e)
if (scale.EnumUpBound >= 0)
{
string presOut = pres.InterpretData(BitUtility.BytesFromHex("0B0B0B0B0B0B0B0B0B0B0B0B0B0B0B0B0B0B0B0B0B0B0B0B0B0B0B0B0B0B0B0B0B0B0B0B0B0B0B0B"), prep);
Console.WriteLine($"{ds.Qualifier} : {prep.Qualifier} @ {presOut} = {pres.Unk1b}, {pres.EnumMaxValue}");
Console.WriteLine($"{ds.Qualifier} : {prep.Qualifier} @ {presOut} = {pres.InternalDataType}, {pres.EnumMaxValue}");
}
}
if (pres.Qualifier == "PRES_ZIELGANG")
Expand Down

0 comments on commit 0863049

Please sign in to comment.