public void Check( BinaryFileSchema schema )
{
foreach (IBfsDataBlock block in schema.DatablockList)
{
if (!(block is IBfsStructType))
continue;
//Clear before each run as nodes will otherwise be seen as visited in the next data block.
topoDictionary.Clear();
IBfsStructType structType = block as IBfsStructType;
BfsTopologicalSorting topological = new BfsTopologicalSorting();
BfsTopologicalNode prevField = null;
foreach ( BfsStructField field in structType.StructFieldList)
{
BfsTopologicalNode node = GetTopoNode(field);
topological.Nodes.Add(node);
//Make each struct field dependent on the previous field.
if (prevField != null)
node.Nodes.Add(prevField);
else
prevField = node;
if (field.Conditional != null)
foreach (BfsExpressionVariable expVar in field.Conditional.DependantVariables)
node.Nodes.Add(GetTopoNode(expVar.LastField));
if (field.PrimitiveType.ArrayExtension != null && field.PrimitiveType.ArrayExtension is BfsKnownArray)
{
BfsKnownArray knownArray = field.PrimitiveType.ArrayExtension as BfsKnownArray;
foreach (BfsExpressionVariable expVar in knownArray.Expression.DependantVariables)
node.Nodes.Add(GetTopoNode(expVar.LastField));
}
}
//Add all the structure field as well as their dependancies
foreach (BfsLocalField local in structType.LocalFieldList)
{
BfsTopologicalNode node = GetTopoNode(local);
if(local.AssignmentExpression != null)
foreach (BfsExpressionVariable expVar in local.AssignmentExpression.DependantVariables)
node.Nodes.Add(GetTopoNode(expVar.LastField));
topological.Nodes.Add(node);
}
//Find the execution/parse order of the struct fields and local fields by performing a topological sort.
structType.ParseOrder = topological.TopologicalSort();
}
foreach (IBfsDataBlock block in schema.DatablockList)
{
//Check that local-fields aren't used in their own intialization expression.
foreach (BfsLocalField local in block.LocalFieldList)
if (local.AssignmentExpression != null)
foreach (BfsExpressionVariable expvar in local.AssignmentExpression.DependantVariables)
if (expvar.NameHierarchy[0] == local)
BfsCompiler.ReportError(local.SourceRange,
"Cannot use local variable in it's own initilization expression");
if (block is IBfsStructType)
{
bool foundEOFcase = false;
BfsStructField eofCase = null;
IBfsStructType structType = (IBfsStructType)block;
HashSet<string> namesSeenSoFar = new HashSet<string>(structType.LocalFields.Keys);
foreach (BfsStructField field in structType.StructFields.Values)
{
if (foundEOFcase)
BfsCompiler.ReportError(field.SourceRange,
"Array '"+eofCase.Name+"' cannot have an EOF case because there are remaining fields in the struct.");
//Check that no variables in conditional expressions or array length expressions aren't read from the file yet.
//Check that struct-fields aren't used in their conditional expression.
if (field.Conditional != null)
foreach (BfsExpressionVariable var in field.Conditional.DependantVariables)
if (!namesSeenSoFar.Contains(var.NameHierarchy[0].Name) && !(var.NameHierarchy[0] is BfsEnumAliasExp))
BfsCompiler.ReportError(var.SourceRange,
" The variable '" + var.ToString() + "' cannot be used before it is read from the file.");
if (field.FieldType.ArrayExtension != null && field.FieldType.ArrayExtension is BfsKnownArray)
{
BfsKnownArray knownArray = field.FieldType.ArrayExtension as BfsKnownArray;
foreach (BfsExpressionVariable var in knownArray.Expression.DependantVariables)
if (!namesSeenSoFar.Contains(var.NameHierarchy[0].Name) && !(var.NameHierarchy[0] is BfsEnumAliasExp))
BfsCompiler.ReportError(var.SourceRange,
" The variable '" + var.ToString() + "' cannot be used before it is read from the file.");
}
namesSeenSoFar.Add(field.Name);
//Check that no struct fields come after an unknown array extension only terminating at EOF
//Check that no stopcases comes after an EOF
if (field.FieldType.ArrayExtension is BfsUnknownArray)
{
BfsUnknownArray extension = field.FieldType.ArrayExtension as BfsUnknownArray;
bool stopcaseafter = false;
foreach (IBfsStopCase stopcase in extension.StopCases)
{
if (stopcaseafter)
BfsCompiler.ReportWarning(stopcase.SourceRange,
"Stopcase after an EOF will never be triggered. Move the EOF to the end of the list.");
if (stopcase is BfsStopCaseEndOfFile)
{
stopcaseafter = true;
foundEOFcase = true;
eofCase = field;
}
}
}
}
}
}
}
