bool CScanner::SkipWhiteSpace()
{
enum EScannerState
{
SEARCH_FOR_WHITE_SPACE,
NEXT_TOKEN,
BEGIN_COMMENT,
C_COMMENT_BODY,
CPP_COMMENT_BODY,
CPP_COMMENT_GOING_NEWLINE,
PREPARE_TO_EXIT_C_COMMENT_BLOCK,
PREPARE_TO_EXIT_CPP_COMMENT_BLOCK,
BEGIN_PP,
PP_GOING_NEW_LINE,
BEGIN_SYMBOL,
BEGIN_IDENTIFIER,
BEGIN_NUMBER,
END_SCAN,
};
char c;
EScannerState State = SEARCH_FOR_WHITE_SPACE;
while (cget() != 0)
{
c = cget();
if (c == '\n')
IncLineCounter();
switch (State)
{
case SEARCH_FOR_WHITE_SPACE:
switch(c)
{
case '\t': case'\n': case '\v': case '\r': case ' ': case '\f':
break;
case '/':
State = BEGIN_COMMENT;
break;
case '#':
State = BEGIN_PP;
break;
default:
return true;
}
break;
case BEGIN_COMMENT:
if (c == '*')
State = C_COMMENT_BODY;
else if (c == '/')
State = CPP_COMMENT_BODY;
else
{
State = BEGIN_SYMBOL;
Pos--;
return true;
}
break;
case C_COMMENT_BODY:
if (c != '*')
break;
else
State = PREPARE_TO_EXIT_C_COMMENT_BLOCK;
break;
case PREPARE_TO_EXIT_C_COMMENT_BLOCK:
switch (c)
{
case '*':
break;
case '/':
State = SEARCH_FOR_WHITE_SPACE;
break;
default:
State = C_COMMENT_BODY;
break;
}
break;
case CPP_COMMENT_BODY:
if (c == '\\')
State = CPP_COMMENT_GOING_NEWLINE;
else if (c != '\r' && c != '\n')
break;
else if (c == '\n')
State = SEARCH_FOR_WHITE_SPACE;
break;
case CPP_COMMENT_GOING_NEWLINE:
if (c == '\r' || c == '\\')
break;
State = CPP_COMMENT_BODY;
break;
case BEGIN_PP:
switch(c)
{
case '\\':
State = PP_GOING_NEW_LINE;
break;
case '\n':
State = SEARCH_FOR_WHITE_SPACE;
break;
default:
break;
}
break;
case PP_GOING_NEW_LINE:
if (c == '\r' || c == '\\')
break;
State = BEGIN_PP;
break;
default:
assert(false);
break;
}
IncPos();
}
if (State == C_COMMENT_BODY || State == PREPARE_TO_EXIT_C_COMMENT_BLOCK)
{
ErrorString = "Unclosed multi-line comment.";
return false;
}
return true;
}
void operator()(const char *begin, const char *end) const
{
IncLineCounter();
}