// Parse
//------------------------------------------------------------------------------
bool BFFParser::Parse( BFFIterator & iter )
{
for (;;)
{
iter.SkipWhiteSpace();
// is this a comment?
if ( iter.IsAtComment() )
{
iter.SkipComment();
continue;
}
const char c = *iter;
switch ( c )
{
case BFF_DECLARE_VAR_INTERNAL:
case BFF_DECLARE_VAR_PARENT:
{
if ( ParseNamedVariableDeclaration( iter ) == false )
{
return false;
}
continue;
}
case BFF_VARIABLE_CONCATENATION:
case BFF_VARIABLE_SUBTRACTION:
{
// concatenation to last used variable
if ( ParseUnnamedVariableModification( iter ) == false )
{
return false;
}
continue;
}
case BFF_SCOPE_OPEN:
{
// start an unnamed scope
if ( ParseUnnamedScope( iter ) == false )
{
return false;
}
continue;
}
case BFF_PREPROCESSOR_START:
{
if ( ParsePreprocessorDirective( iter ) == false )
{
return false;
}
continue;
}
default:
{
if ( iter.IsAtValidFunctionNameCharacter() )
{
if ( ParseFunction( iter ) == false )
{
return false;
}
continue;
}
}
}
iter.SkipWhiteSpace();
if ( iter.IsAtEnd() == false )
{
Error::Error_1010_UnknownConstruct( iter );
return false;
}
break; // cleanly hit end of file
}
return true;
}
// ParseFunction
//------------------------------------------------------------------------------
bool BFFParser::ParseFunction( BFFIterator & iter )
{
ASSERT( iter.IsAtValidFunctionNameCharacter() );
// for variables to be used by this function
BFFStackFrame stackFrame;
BFFIterator functionNameStart( iter );
iter.SkipFunctionName();
if ( iter.IsAtEnd() )
{
Error::Error_1012_UnexpectedEndOfFile( iter );
return false;
}
// check length
if ( functionNameStart.GetDistTo( iter ) > MAX_FUNCTION_NAME_LENGTH )
{
// if it's too long, then it can't be a valid function
Error::Error_1015_UnknownFunction( functionNameStart );
return false;
}
// store function name
AStackString<MAX_FUNCTION_NAME_LENGTH> functionName( functionNameStart.GetCurrent(), iter.GetCurrent() );
const Function * func = Function::Find( functionName );
if ( func == nullptr )
{
Error::Error_1015_UnknownFunction( functionNameStart );
return false;
}
iter.SkipWhiteSpace();
if ( func->IsUnique() && func->GetSeen() )
{
Error::Error_1020_FunctionCanOnlyBeInvokedOnce( functionNameStart, func );
return false;
}
func->SetSeen();
FLOG_INFO( "Function call '%s'", functionName.Get() );
// header, or body?
bool hasHeader = false;
BFFIterator functionArgsStartToken( iter );
BFFIterator functionArgsStopToken( iter );
if ( *iter == BFF_FUNCTION_ARGS_OPEN )
{
// can this function accept a header?
if ( func->AcceptsHeader() == false )
{
Error::Error_1021_UnexpectedHeaderForFunction( iter, func );
return false;
}
// args
if ( iter.ParseToMatchingBrace( BFF_FUNCTION_ARGS_OPEN, BFF_FUNCTION_ARGS_CLOSE ) == false )
{
Error::Error_1022_MissingFunctionHeaderCloseToken( functionArgsStartToken, func );
return false;
}
functionArgsStopToken = iter;
hasHeader = true;
iter++; // skip over closing token
iter.SkipWhiteSpaceAndComments();
}
if ( func->NeedsHeader() && ( hasHeader == false ) )
{
Error::Error_1023_FunctionRequiresAHeader( iter, func );
return false;
}
// some functions have no body
bool hasBody = false;
BFFIterator functionBodyStartToken( iter );
BFFIterator functionBodyStopToken( iter );
if ( func->NeedsBody() )
{
// find body
if ( *iter != BFF_SCOPE_OPEN )
{
Error::Error_1024_FunctionRequiresABody( functionNameStart, func );
return false;
}
if ( iter.ParseToMatchingBrace( BFF_SCOPE_OPEN, BFF_SCOPE_CLOSE ) == false )
{
Error::Error_1025_MissingScopeCloseToken( functionBodyStartToken, func );
return false;
}
functionBodyStopToken = iter;
iter++;
hasBody = true;
}
return func->ParseFunction( functionNameStart,
hasBody ? &functionBodyStartToken : nullptr,
hasBody ? &functionBodyStopToken : nullptr,
hasHeader ? &functionArgsStartToken : nullptr,
hasHeader ? &functionArgsStopToken : nullptr );}