private static int ParseClass(char[] data, int i, int _out, Bitset bs, bool icase, bool skipspaces, bool unicode, bool xml)
{
char c;
int prev=-1;
bool isFirst=true, setFirst=false, inRange=false;
Bitset bs1=null;
StringBuilder sb=null;
for(;i<_out;isFirst=setFirst,setFirst=false){
switch(c=data[i++]){
case ']':
if(isFirst) break; //treat as normal char
if(inRange){
bs.SetChar('-');
}
if(prev>=0){
char c1=(char)prev;
if(icase){
bs.SetChar(char.ToLower(c1));
bs.SetChar(char.ToUpper(c1));
}
else bs.SetChar(c1);
}
return i;
case '-':
if(isFirst) break;
if(inRange) break;
inRange=true;
continue;
case '[':
if(inRange && xml) {
if(prev>=0) bs.SetChar((char)prev);
if(bs1==null) bs1 = new Bitset();
else bs1.Reset();
i=ParseClass(data,i,_out,bs1,icase,skipspaces,unicode,xml);
bs.Subtract(bs1);
inRange=false;
prev=-1;
continue;
}
else break;
case '^':
if(isFirst){
bs.SetPositive(false);
setFirst=true;
continue;
}
break;
case ' ':
case '\r':
case '\n':
case '\t':
case '\f':
if(skipspaces) continue;
else break;
case '\\':
Bitset negatigeClass = null;
bool inv = false;
bool handle_special = false;
switch(c=data[i++]){
case 'r':
c='\r';
handle_special = true;
break;
case 'n':
c='\n';
handle_special = true;
break;
case 'e':
c='\u001B';
handle_special = true;
break;
case 't':
c='\t';
handle_special = true;
break;
case 'f':
c='\f';
handle_special = true;
break;
case 'u':
if(i>=_out-4) throw new PatternSyntaxException("incomplete escape sequence \\uXXXX");
c=(char)((ToHexDigit(c)<<12)
+(ToHexDigit(data[i++])<<8)
+(ToHexDigit(data[i++])<<4)
+ToHexDigit(data[i++]));
handle_special = true;
break;
case 'v':
c=(char)((ToHexDigit(c)<<24)+
(ToHexDigit(data[i++])<<16)+
(ToHexDigit(data[i++])<<12)+
(ToHexDigit(data[i++])<<8)+
(ToHexDigit(data[i++])<<4)+
ToHexDigit(data[i++]));
handle_special = true;
break;
case 'b':
c=(char)8; // backspace
handle_special = true;
break;
case 'x':{ // hex 2-digit number
int hex=0;
char d;
if((d=data[i++])=='{'){
while((d=data[i++])!='}'){
hex=(hex<<4)+ToHexDigit(d);
}
if(hex>0xffff) throw new PatternSyntaxException("\\x{<out of range>}");
}
else{
hex=(ToHexDigit(d)<<4)+ToHexDigit(data[i++]);
}
c=(char)hex;
handle_special = true;
break;
}
case '0': // oct 2- or 3-digit number
case 'o': // oct 2- or 3-digit number
int oct=0;
for(;;){
char d=data[i++];
if(d>='0' && d<='7'){
oct*=8;
oct+=d-'0';
if(oct>0xffff) break;
}
else {
i--;
break;
}
}
c=(char)oct;
handle_special = true;
break;
case 'm': // decimal number -> char
int dec=0;
for(;;){
char d=data[i++];
if(d>='0' && d<='9'){
dec*=10;
dec+=d-'0';
if(dec>0xffff) break;
} else {
i--;
break;
}
}
c=(char)dec;
handle_special = true;
break;
case 'c': // ctrl-char
c=(char)(data[i++]&0x1f);
handle_special = true;
break;
case 'D': // non-digit
negatigeClass = unicode ? UNONDIGIT : NONDIGIT;
break;
case 'S': // space
negatigeClass =unicode ? UNONSPACE : NONSPACE;
break;
case 'W': // space
negatigeClass = unicode ? UNONWORDCHAR : NONWORDCHAR;
break;
case 'd': // digit
if(inRange) throw new PatternSyntaxException("illegal range: [..."+prev+"-\\d...]");
bs.SetDigit(unicode);
continue;
case 's': // digit
if(inRange) throw new PatternSyntaxException("illegal range: [..."+prev+"-\\s...]");
bs.SetSpace(unicode);
continue;
case 'w': // digit
if(inRange) throw new PatternSyntaxException("illegal range: [..."+prev+"-\\w...]");
bs.SetWordChar(unicode);
continue;
case 'P': // \\P{..}
inv=true;
goto case 'p';
case 'p': // \\p{..}
if(inRange) throw new PatternSyntaxException("illegal range: [..."+prev+"-\\w...]");
if(sb==null) sb = new StringBuilder();
else sb.Length = 0;
i=ParseName(data,i,_out,sb,skipspaces);
Bitset nc=GetNamedClass(sb.ToString());
if(nc==null) throw new PatternSyntaxException("unknown named class: {"+sb+"}");
bs.Add(nc,inv);
continue;
default:
handle_special = true;
break;
}
if(handle_special) break;
if(inRange) throw new PatternSyntaxException("illegal range: [..."+prev+"-\\"+c+"...]");
bs.Add(negatigeClass);
continue;
default:
break;
}
if(prev<0){
prev=c;
inRange=false;
continue;
}
if(!inRange){
char c1=(char)prev;
if(icase){
bs.SetChar(char.ToLower(c1));
bs.SetChar(char.ToUpper(c1));
}
else bs.SetChar(c1);
prev=c;
}
else {
if(prev>c) throw new PatternSyntaxException("illegal range: "+prev+">"+c);
char c0=(char)prev;
inRange=false;
prev=-1;
if(icase){
bs.SetRange(char.ToLower(c0),char.ToLower(c));
bs.SetRange(char.ToUpper(c0),char.ToUpper(c));
}
else bs.SetRange(c0,c);
}
}
throw new PatternSyntaxException("unbalanced brackets in a class def");
}
private static void InitPosixClasses()
{
Bitset lower = new Bitset();
lower.SetRange('a','z');
RegisterClass("Lower", lower, posixClasses);
Bitset upper = new Bitset();
upper.SetRange('A','Z');
RegisterClass("Upper",upper,posixClasses);
Bitset ascii = new Bitset();
ascii.SetRange((char)0,(char)0x7f);
RegisterClass("ASCII",ascii,posixClasses);
Bitset alpha = new Bitset();
alpha.Add(lower);
alpha.Add(upper);
RegisterClass("Alpha",alpha,posixClasses);
Bitset digit = new Bitset();
digit.SetRange('0','9');
RegisterClass("Digit",digit,posixClasses);
Bitset alnum = new Bitset();
alnum.Add(alpha);
alnum.Add(digit);
RegisterClass("Alnum",alnum,posixClasses);
Bitset punct = new Bitset();
punct.SetChars("!\"#$%&'()*+,-./:;<=>?@[\\]^_`{|}~");
RegisterClass("Punct",punct,posixClasses);
Bitset graph = new Bitset();
graph.Add(alnum);
graph.Add(punct);
RegisterClass("Graph",graph,posixClasses);
RegisterClass("Print",graph,posixClasses);
Bitset blank = new Bitset();
blank.SetChars(" \t");
RegisterClass("Blank",blank,posixClasses);
Bitset cntrl = new Bitset();
cntrl.SetRange((char)0,(char)0x1f);
cntrl.SetChar((char)0x7f);
RegisterClass("Cntrl",cntrl,posixClasses);
Bitset xdigit = new Bitset();
xdigit.SetRange('0','9');
xdigit.SetRange('a','f');
xdigit.SetRange('A','F');
RegisterClass("XDigit",xdigit,posixClasses);
Bitset space = new Bitset();
space.SetChars(" \t\n\r\f\u000b");
RegisterClass("Space",space,posixClasses);
}