unsafe public DefSegment(byte *pb, ref uint idx, bool allowGlobal = true)
{
this.offset = 0;
this.data = null;
switch ((Instruction)pb[idx])
{
case Instruction.global_get:
if (allowGlobal == false)
{
throw new System.Exception("Initializer expression cannot reference a mutable global.");
}
this.offsetSource = Source.Global;
break;
case Instruction.i32_const:
this.offsetSource = Source.Const;
break;
default:
throw new System.Exception("Offset size for data segment must be either a global.get or i32.const.");
}
++idx;
this.offset = BinParse.LoadUnsignedLEB32(pb, ref idx);
if (pb[idx] != (int)Instruction.end)
{
throw new System.Exception("Unexpected end of expression.");
}
++idx;
}
unsafe public static Module LoadBinary(byte *pb, ref uint idx, int endIdx)
{
// https://www.reddit.com/r/WebAssembly/comments/9vq019/is_anyone_learning_webassembly_in_binary_im_stuck/
// https://webassembly.github.io/wabt/demo/wat2wasm/
if (*((int *)(&pb[idx])) != BinParse.WASM_BINARY_MAGIC)
{
return(null);
}
idx += 4;
if (*(int *)&pb[idx] != BinParse.WASM_BINARY_VERSION)
{
return(null);
}
idx += 4;
Module ret = new Module();
while (idx < endIdx)
{
Bin.Section sectionCode = (Bin.Section)pb[idx];
++idx;
uint sectionSize = BinParse.LoadUnsignedLEB32(pb, ref idx);
if (sectionCode == Bin.Section.CustomSec)
{
uint end = idx + sectionSize;
while (true)
{
return(ret);
// TODO: Considered end and unprocessed for now.
//
// uint nameLen = LoadUnsignedLEB32(pb, ref idx);
// string customSecName = LoadString(pb, nameLen, ref idx);
//
// uint subType = LoadUnsignedLEB32(pb, ref idx);
// uint subSize = LoadUnsignedLEB32(pb, ref idx);
}
}
else if (sectionCode == Bin.Section.TypeSec)
{
uint numTypes = BinParse.LoadUnsignedLEB32(pb, ref idx);
for (uint i = 0; i < numTypes; ++i)
{
Bin.TypeID type = (Bin.TypeID)BinParse.LoadUnsignedLEB32(pb, ref idx);
if (type == Bin.TypeID.Function)
{
FunctionType fty = new FunctionType();
fty.typeid = (uint)type;
ret.types.Add(fty);
uint numParams = BinParse.LoadUnsignedLEB32(pb, ref idx);
for (uint j = 0; j < numParams; ++j)
{
FunctionType.DataOrgInfo paramInfo = new FunctionType.DataOrgInfo();
paramInfo.type = (Bin.TypeID)BinParse.LoadUnsignedLEB32(pb, ref idx);
fty.paramTypes.Add(paramInfo);
}
uint numResults = BinParse.LoadUnsignedLEB32(pb, ref idx);
for (uint j = 0; j < numResults; ++j)
{
FunctionType.DataOrgInfo resultInfo = new FunctionType.DataOrgInfo();
resultInfo.type = (Bin.TypeID)BinParse.LoadUnsignedLEB32(pb, ref idx);
fty.resultTypes.Add(resultInfo);
}
fty.InitializeOrganization();
}
else
{
}
}
}
else if (sectionCode == Bin.Section.ImportSec)
{
uint numImports = BinParse.LoadUnsignedLEB32(pb, ref idx);
for (uint i = 0; i < numImports; ++i)
{
uint modnameLen = BinParse.LoadUnsignedLEB32(pb, ref idx);
string modName = LoadString(pb, modnameLen, ref idx);
uint fieldnameLen = BinParse.LoadUnsignedLEB32(pb, ref idx);
string fieldName = LoadString(pb, fieldnameLen, ref idx);
ImportType importTy = (ImportType)BinParse.LoadUnsignedLEB32(pb, ref idx);
switch (importTy)
{
case ImportType.TypeIndex:
{
uint fnTyIdx = BinParse.LoadUnsignedLEB32(pb, ref idx);
FunctionType fnTy = ret.types[(int)fnTyIdx];
ret.storeDecl.AddFunctionImp(modName, fieldName, fnTy);
}
break;
case ImportType.TableType:
{
const int FLAG_HASMAX = 0x01;
const int FLAG_OTHERS = ~(FLAG_HASMAX);
// We may be able top unify parts of this code with non-imported tables
uint type = BinParse.LoadUnsignedLEB32(pb, ref idx);
uint flags = BinParse.LoadUnsignedLEB32(pb, ref idx);
uint initial = BinParse.LoadUnsignedLEB32(pb, ref idx);
uint?max = null;
if ((flags & FLAG_HASMAX) != 0)
{
max = BinParse.LoadUnsignedLEB32(pb, ref idx);
}
if ((flags & FLAG_OTHERS) != 0)
{
throw new System.Exception("Encountered unknown flags for imported table.");
}
ret.storeDecl.AddTableImp(modName, fieldName, (Bin.TypeID)type, initial, max);
}
break;
case ImportType.MemType:
{
const int FLAG_HASMAX = 0x01;
const int FLAG_OTHERS = ~(FLAG_HASMAX);
// We may be able to unify parts of this code with non-imported memory
uint flags = BinParse.LoadUnsignedLEB32(pb, ref idx);
uint initial = BinParse.LoadUnsignedLEB32(pb, ref idx);
uint?max = null;
if ((flags & FLAG_HASMAX) != 0)
{
max = BinParse.LoadUnsignedLEB32(pb, ref idx);
}
if ((flags & FLAG_OTHERS) != 0)
{
throw new System.Exception("Encountered unknown flags for imported memory.");
}
ret.storeDecl.AddMemoryImp(modName, fieldName, initial, initial, max);
}
break;
case ImportType.GlobalType:
{
uint type = BinParse.LoadUnsignedLEB32(pb, ref idx);
uint mutability = BinParse.LoadUnsignedLEB32(pb, ref idx);
ret.storeDecl.AddGlobalImp(modName, fieldName, (Bin.TypeID)type, mutability != 0);
}
break;
}
}
}
else if (sectionCode == Bin.Section.FunctionSec)
{
uint numFunctions = BinParse.LoadUnsignedLEB32(pb, ref idx);
for (uint i = 0; i < numFunctions; ++i)
{
Function function = new Function(ret);
uint fnType = BinParse.LoadUnsignedLEB32(pb, ref idx);
function.typeidx = fnType;
function.fnType = ret.types[(int)fnType];
ret.storeDecl.AddFunctionLoc(function.fnType);
ret.functions.Add(function);
}
}
else if (sectionCode == Bin.Section.TableSec)
{
uint numTables = BinParse.LoadUnsignedLEB32(pb, ref idx);
for (uint i = 0; i < numTables; ++i)
{
const int FLAG_HASMAX = 0x01;
const int FLAG_OTHERS = ~(FLAG_HASMAX);
Bin.TypeID ty = (Bin.TypeID)BinParse.LoadUnsignedLEB32(pb, ref idx);
uint flags = BinParse.LoadUnsignedLEB32(pb, ref idx);
uint initial = BinParse.LoadUnsignedLEB32(pb, ref idx);
uint?max = null;
if ((flags & FLAG_HASMAX) != 0)
{
max = BinParse.LoadUnsignedLEB32(pb, ref idx);
}
if ((flags & FLAG_OTHERS) != 0)
{
throw new System.Exception("Table section contains unsupported flags.");
}
ret.storeDecl.AddTableLoc(ty, initial, max);
}
}
else if (sectionCode == Bin.Section.MemorySec)
{
// Prepare the declaration of memory regions.
//
// Note that this is only prepping for the data payloads, actual
// parsing of that data happens in the Data section.
uint numMems = BinParse.LoadUnsignedLEB32(pb, ref idx); // Right now this is assumed to be 1
for (uint i = 0; i < numMems; ++i)
{
const int FLAG_HASMAX = 0x01;
const int FLAG_OTHERS = ~(FLAG_HASMAX);
uint memFlags = BinParse.LoadUnsignedLEB32(pb, ref idx);
uint memInitialPageCt = BinParse.LoadUnsignedLEB32(pb, ref idx);
uint?memMaxPageCt = null;
if ((memFlags & FLAG_HASMAX) != 0)
{
memMaxPageCt = BinParse.LoadUnsignedLEB32(pb, ref idx);
}
if ((memFlags & FLAG_OTHERS) != 0)
{
throw new System.Exception("Memory section contains unsupported flags.");
}
ret.storeDecl.AddMemoryLoc(memInitialPageCt, memInitialPageCt, memMaxPageCt);
}
}
else if (sectionCode == Bin.Section.GlobalSec)
{
uint numGlobals = BinParse.LoadUnsignedLEB32(pb, ref idx);
for (uint i = 0; i < numGlobals; ++i)
{
const int FLAG_MUTABLE = 0x01;
const int FLAG_OTHERS = ~(FLAG_MUTABLE);
uint globType = BinParse.LoadUnsignedLEB32(pb, ref idx);
uint globFlags = BinParse.LoadUnsignedLEB32(pb, ref idx);
bool mutable = (globFlags & FLAG_MUTABLE) != 0;
if ((globFlags & FLAG_OTHERS) != 0)
{
throw new System.Exception("Global section contains unsupported flags.");
}
// For now we're just going to assume they do a type.const, then the value,
// and then an end.
//
// I actually haven't read the specs to see what's allowed here.
if (globType == (int)Bin.TypeID.Int32)
{
AssertConsumeByte(pb, ref idx, (byte)Instruction.i32_const);
int idef = BinParse.LoadSignedLEB32(pb, ref idx);
AssertConsumeByte(pb, ref idx, (byte)Instruction.end);
ret.storeDecl.AddGlobalLoc(idef, mutable);
}
else if (globType == (int)Bin.TypeID.Float32)
{
AssertConsumeByte(pb, ref idx, (byte)Instruction.f32_const);
float fdef = *(float *)&pb[idx];
idx += 4;
AssertConsumeByte(pb, ref idx, (byte)Instruction.end);
ret.storeDecl.AddGlobalLoc(fdef, mutable);
}
else if (globType == (int)Bin.TypeID.Int64)
{
AssertConsumeByte(pb, ref idx, (byte)Instruction.i64_const);
long ldef = BinParse.LoadSignedLEB64(pb, ref idx);
AssertConsumeByte(pb, ref idx, (byte)Instruction.end);
ret.storeDecl.AddGlobalLoc(ldef, mutable);
}
else if (globType == (int)Bin.TypeID.Float64)
{
AssertConsumeByte(pb, ref idx, (byte)Instruction.f64_const);
double ddef = *(float *)&pb[idx];
idx += 8;
AssertConsumeByte(pb, ref idx, (byte)Instruction.end);
ret.storeDecl.AddGlobalLoc(ddef, mutable);
}
else
{
throw new System.Exception("Unexpected global type.");
}
}
}
else if (sectionCode == Bin.Section.ExportSec)
{
uint numExports = BinParse.LoadUnsignedLEB32(pb, ref idx);
for (uint i = 0; i < numExports; ++i)
{
uint strLen = BinParse.LoadUnsignedLEB32(pb, ref idx);
string name = LoadString(pb, strLen, ref idx);
uint kind = BinParse.LoadUnsignedLEB32(pb, ref idx);
uint index = BinParse.LoadUnsignedLEB32(pb, ref idx);
Export export = new Export();
export.name = name;
export.kind = (ImportType)kind;
export.index = index;
ret.exports.Add(export);
}
}
else if (sectionCode == Bin.Section.StartSec)
{
ret.startFnIndex = BinParse.LoadUnsignedLEB32(pb, ref idx);
ret.ValidateStartFunction(true);
}
else if (sectionCode == Bin.Section.ElementSec)
{
uint numSegments = BinParse.LoadUnsignedLEB32(pb, ref idx);
if (numSegments == 0)
{
continue;
}
if (ret.storeDecl.tables.Count < 1)
{
throw new System.Exception("Element(s) specified when no tables are defined.");
}
DefTable defTable = ret.storeDecl.tables[0];
for (uint i = 0; i < numSegments; ++i)
{
// Table index
uint flags = BinParse.LoadUnsignedLEB32(pb, ref idx);
DefSegment ds = new DefSegment(pb, ref idx, false);
Bin.TypeID tabTy = ret.storeDecl.tables[0].type;
uint tySize = DataStore.GetTypeIDSize(tabTy);
uint elemCt = BinParse.LoadUnsignedLEB32(pb, ref idx);
ds.data = new byte[elemCt * tySize];
fixed(byte *ptabdefs = ds.data)
{
switch (tabTy)
{
case Bin.TypeID.FuncRef:
case Bin.TypeID.Int32:
for (int j = 0; j < elemCt; ++j)
{
((int *)ptabdefs)[j] = BinParse.LoadSignedLEB32(pb, ref idx);
}
break;
case Bin.TypeID.Float32:
for (int j = 0; j < elemCt; ++j)
{
((float *)ptabdefs)[j] = *(float *)pb;
idx += 4;
}
break;
case Bin.TypeID.Int64:
for (int j = 0; j < elemCt; ++j)
{
((long *)ptabdefs)[j] = BinParse.LoadSignedLEB64(pb, ref idx);
}
break;
case Bin.TypeID.Float64:
for (int j = 0; j < elemCt; ++j)
{
((double *)ptabdefs)[j] = *(double *)pb;
idx += 8;
}
break;
}
}
}
}
else if (sectionCode == Bin.Section.CodeSec)
{
uint numFunctions = BinParse.LoadUnsignedLEB32(pb, ref idx);
for (uint i = 0; i < numFunctions; ++i)
{
Function function = ret.functions[(int)i];
uint bodySize = BinParse.LoadUnsignedLEB32(pb, ref idx);
uint end = idx + bodySize;
uint localsCount = BinParse.LoadUnsignedLEB32(pb, ref idx);
for (int j = 0; j < localsCount; ++j)
{
// The number of consecutive occurences of this type
uint localTyCt = BinParse.LoadUnsignedLEB32(pb, ref idx);
// The type to place on the stack. The quantity of how many
// is specified in localTyCt.
uint type = BinParse.LoadUnsignedLEB32(pb, ref idx);
for (int k = 0; k < localTyCt; ++k)
{
FunctionType.DataOrgInfo doi = new FunctionType.DataOrgInfo();
doi.type = (Bin.TypeID)type;
function.localTypes.Add(doi);
}
}
function.InitializeOrganization();
uint size = end - idx;
function.expression = new byte[size];
System.Runtime.InteropServices.Marshal.Copy(
(System.IntPtr)(int *)(&pb[idx]),
function.expression,
(int)0,
(int)size);
idx = end;
}
for (uint i = 0; i < numFunctions; ++i)
{
ret.functions[(int)i].ExpandExpressionToBeUsable(ret);
}
}
else if (sectionCode == Bin.Section.DataSec)
{
uint numData = BinParse.LoadUnsignedLEB32(pb, ref idx);
if (numData == 0)
{
continue;
}
if (ret.storeDecl.memories.Count < 1)
{
throw new System.Exception("Data(s) specified when no mems are defined.");
}
for (uint i = 0; i < numData; ++i)
{
uint segHeaderFlags = BinParse.LoadUnsignedLEB32(pb, ref idx);
DefMem dmem = ret.storeDecl.memories[0];
DefSegment ds = new DefSegment(pb, ref idx, false);
uint dataSz = BinParse.LoadUnsignedLEB32(pb, ref idx);
ds.data = new byte[dataSz];
// We're going to do the copy manually, but if there's a C#
// low-level copy function that also does this, that would be
// prefered.
for (uint j = 0; j < dataSz; ++j)
{
ds.data[j] = pb[idx + j];
}
dmem.AddDefault(ds);
//ret.storeDecl.memories[(int)i] = dmem;
ret.storeDecl.memories[0] = dmem;
idx += dataSz;
}
}
else
{
throw new System.Exception("Encountered unknown Module section.");
}
}
++idx;
return(ret);
}