lexer.cpp

来自「konqueror3 embedded版本, KDE环境下的当家浏览器的嵌入式版」· C++ 代码 · 共 900 行 · 第 1/2 页

  fprintf(stderr, "%s ", buffer8);
#endif

  long double dval = 0;
  if (state == Number) {
    dval = strtod(buffer8, 0L);
  } else if (state == Hex) { // scan hex numbers
    dval = 0;
    if (buffer8[0] == '0' && (buffer8[1] == 'x' || buffer8[1] == 'X')) {
      for (const char *p = buffer8+2; *p; p++) {
	if (!isHexDigit(*p)) {
	  dval = 0;
	  break;
	}
	dval = dval * 16 + convertHex(*p);
      }
    }
    state = Number;
  } else if (state == Octal) {   // scan octal number
    dval = 0;
    if (buffer8[0] == '0') {
      for (const char *p = buffer8+1; *p; p++) {
	if (*p < '0' || *p > '7') {
	  dval = 0;
	  break;
	}
	dval = dval * 8 + *p - '0';
      }
    }
    state = Number;
  }

#ifdef KJS_DEBUG_LEX
  switch (state) {
  case Eof:
    printf("(EOF)\n");
    break;
  case Other:
    printf("(Other)\n");
    break;
  case Identifier:
    printf("(Identifier)/(Keyword)\n");
    break;
  case String:
    printf("(String)\n");
    break;
  case Number:
    printf("(Number)\n");
    break;
  default:
    printf("(unknown)");
  }
#endif

  if (state != Identifier && eatNextIdentifier)
    eatNextIdentifier = false;

  restrKeyword = false;
  delimited = false;
  kjsyylloc.first_line = yylineno; // ???
  kjsyylloc.last_line = yylineno;

  switch (state) {
  case Eof:
    token = 0;
    break;
  case Other:
    if(token == '}' || token == ';') {
      delimited = true;
    }
    break;
  case Identifier:
    if ((token = Lookup::find(&mainTable, buffer16, pos16)) < 0) {
      // Lookup for keyword failed, means this is an identifier
      // Apply anonymous-function hack below (eat the identifier)
      if (eatNextIdentifier) {
        eatNextIdentifier = false;
#ifdef KJS_VERBOSE
        UString debugstr(buffer16, pos16); fprintf(stderr,"Anonymous function hack: eating identifier %s\n",debugstr.ascii());
#endif
        token = lex();
        break;
      }
      /* TODO: close leak on parse error. same holds true for String */
      kjsyylval.ident = makeIdentifier(buffer16, pos16);
      token = IDENT;
      break;
    }

    eatNextIdentifier = false;
    // Hack for "f = function somename() { ... }", too hard to get into the grammar
    // Same for building an array with function pointers ( 'name', func1, 'name2', func2 )
    // There are lots of other uses, we really have to get this into the grammar
    if ( token == FUNCTION &&
         ( lastToken == '=' || lastToken == ',' || lastToken == '(' ) )
            eatNextIdentifier = true;

    if (token == CONTINUE || token == BREAK ||
        token == RETURN || token == THROW)
      restrKeyword = true;
    break;
  case String:
    kjsyylval.ustr = makeUString(buffer16, pos16);
    token = STRING;
    break;
  case Number:
    kjsyylval.dval = dval;
    token = NUMBER;
    break;
  case Bad:
    foundBad = true;
    return -1;
  default:
    assert(!"unhandled numeration value in switch");
    return -1;
  }
  lastToken = token;
  return token;
}

bool Lexer::isWhiteSpace(unsigned short c)
{
  return (c == ' ' || c == '\t' ||
          c == 0x0b || c == 0x0c || c == 0xa0);
}

bool Lexer::isIdentLetter(unsigned short c)
{
  // Allow any character in the Unicode categories
  // Uppercase letter (Lu), Lowercase letter (Ll),
  // Titlecase letter (Lt)", Modifier letter (Lm),
  // Other letter (Lo), or Letter number (Nl).
  // Also see: http://www.unicode.org/Public/UNIDATA/UnicodeData.txt */
  return (c >= 'a' && c <= 'z' ||
          c >= 'A' && c <= 'Z' ||
          // A with grave - O with diaeresis
          c >= 0x00c0 && c <= 0x00d6 ||
          // O with stroke - o with diaeresis
          c >= 0x00d8 && c <= 0x00f6 ||
          // o with stroke - turned h with fishook and tail
          c >= 0x00f8 && c <= 0x02af ||
          // Greek etc. TODO: not precise
          c >= 0x0388 && c <= 0x1ffc ||
          c == '$' || c == '_');
  /* TODO: use complete category table */
}

bool Lexer::isDecimalDigit(unsigned short c)
{
  return (c >= '0' && c <= '9');
}

bool Lexer::isHexDigit(unsigned short c)
{
  return (c >= '0' && c <= '9' ||
          c >= 'a' && c <= 'f' ||
          c >= 'A' && c <= 'F');
}

bool Lexer::isOctalDigit(unsigned short c)
{
  return (c >= '0' && c <= '7');
}

int Lexer::matchPunctuator(unsigned short c1, unsigned short c2,
                              unsigned short c3, unsigned short c4)
{
  if (c1 == '>' && c2 == '>' && c3 == '>' && c4 == '=') {
    shift(4);
    return URSHIFTEQUAL;
  } else if (c1 == '=' && c2 == '=' && c3 == '=') {
    shift(3);
    return STREQ;
  } else if (c1 == '!' && c2 == '=' && c3 == '=') {
    shift(3);
    return STRNEQ;
   } else if (c1 == '>' && c2 == '>' && c3 == '>') {
    shift(3);
    return URSHIFT;
  } else if (c1 == '<' && c2 == '<' && c3 == '=') {
    shift(3);
    return LSHIFTEQUAL;
  } else if (c1 == '>' && c2 == '>' && c3 == '=') {
    shift(3);
    return RSHIFTEQUAL;
  } else if (c1 == '<' && c2 == '=') {
    shift(2);
    return LE;
  } else if (c1 == '>' && c2 == '=') {
    shift(2);
    return GE;
  } else if (c1 == '!' && c2 == '=') {
    shift(2);
    return NE;
  } else if (c1 == '+' && c2 == '+') {
    shift(2);
    if (terminator)
      return AUTOPLUSPLUS;
    else
      return PLUSPLUS;
  } else if (c1 == '-' && c2 == '-') {
    shift(2);
    if (terminator)
      return AUTOMINUSMINUS;
    else
      return MINUSMINUS;
  } else if (c1 == '=' && c2 == '=') {
    shift(2);
    return EQEQ;
  } else if (c1 == '+' && c2 == '=') {
    shift(2);
    return PLUSEQUAL;
  } else if (c1 == '-' && c2 == '=') {
    shift(2);
    return MINUSEQUAL;
  } else if (c1 == '*' && c2 == '=') {
    shift(2);
    return MULTEQUAL;
  } else if (c1 == '/' && c2 == '=') {
    shift(2);
    return DIVEQUAL;
  } else if (c1 == '&' && c2 == '=') {
    shift(2);
    return ANDEQUAL;
  } else if (c1 == '^' && c2 == '=') {
    shift(2);
    return XOREQUAL;
  } else if (c1 == '%' && c2 == '=') {
    shift(2);
    return MODEQUAL;
  } else if (c1 == '|' && c2 == '=') {
    shift(2);
    return OREQUAL;
  } else if (c1 == '<' && c2 == '<') {
    shift(2);
    return LSHIFT;
  } else if (c1 == '>' && c2 == '>') {
    shift(2);
    return RSHIFT;
  } else if (c1 == '&' && c2 == '&') {
    shift(2);
    return AND;
  } else if (c1 == '|' && c2 == '|') {
    shift(2);
    return OR;
  }

  switch(c1) {
    case '=':
    case '>':
    case '<':
    case ',':
    case '!':
    case '~':
    case '?':
    case ':':
    case '.':
    case '+':
    case '-':
    case '*':
    case '/':
    case '&':
    case '|':
    case '^':
    case '%':
    case '(':
    case ')':
    case '{':
    case '}':
    case '[':
    case ']':
    case ';':
      shift(1);
      return static_cast<int>(c1);
    default:
      return -1;
  }
}

unsigned short Lexer::singleEscape(unsigned short c) const
{
  switch(c) {
  case 'b':
    return 0x08;
  case 't':
    return 0x09;
  case 'n':
    return 0x0A;
  case 'v':
    return 0x0B;
  case 'f':
    return 0x0C;
  case 'r':
    return 0x0D;
  case '"':
    return 0x22;
  case '\'':
    return 0x27;
  case '\\':
    return 0x5C;
  default:
    return c;
  }
}

unsigned short Lexer::convertOctal(unsigned short c1, unsigned short c2,
                                      unsigned short c3) const
{
  return ((c1 - '0') * 64 + (c2 - '0') * 8 + c3 - '0');
}

unsigned char Lexer::convertHex(unsigned short c)
{
  if (c >= '0' && c <= '9')
    return (c - '0');
  else if (c >= 'a' && c <= 'f')
    return (c - 'a' + 10);
  else
    return (c - 'A' + 10);
}

unsigned char Lexer::convertHex(unsigned short c1, unsigned short c2)
{
  return ((convertHex(c1) << 4) + convertHex(c2));
}

UChar Lexer::convertUnicode(unsigned short c1, unsigned short c2,
                                     unsigned short c3, unsigned short c4)
{
  return UChar((convertHex(c1) << 4) + convertHex(c2),
               (convertHex(c3) << 4) + convertHex(c4));
}

void Lexer::record8(unsigned short c)
{
  assert(c <= 0xff);

  // enlarge buffer if full
  if (pos8 >= size8 - 1) {
    char *tmp = new char[2 * size8];
    memcpy(tmp, buffer8, size8 * sizeof(char));
    delete [] buffer8;
    buffer8 = tmp;
    size8 *= 2;
  }

  buffer8[pos8++] = (char) c;
}

void Lexer::record16(UChar c)
{
  // enlarge buffer if full
  if (pos16 >= size16 - 1) {
    UChar *tmp = new UChar[2 * size16];
    memcpy(tmp, buffer16, size16 * sizeof(UChar));
    delete [] buffer16;
    buffer16 = tmp;
    size16 *= 2;
  }

  buffer16[pos16++] = c;
}

bool Lexer::scanRegExp()
{
  pos16 = 0;
  bool lastWasEscape = false;
  bool inBrackets = false;

  while (1) {
    if (current == '\r' || current == '\n' || current == 0)
      return false;
    else if (current != '/' || lastWasEscape == true || inBrackets == true)
    {
        // keep track of '[' and ']'
        if ( !lastWasEscape ) {
          if ( current == '[' && !inBrackets )
            inBrackets = true;
          if ( current == ']' && inBrackets )
            inBrackets = false;
        }
        record16(current);
        lastWasEscape =
            !lastWasEscape && (current == '\\');
    }
    else { // end of regexp
      pattern = UString(buffer16, pos16);
      pos16 = 0;
      shift(1);
      break;
    }
    shift(1);
  }

  while (isIdentLetter(current)) {
    record16(current);
    shift(1);
  }
  flags = UString(buffer16, pos16);

  return true;
}


void Lexer::doneParsing()
{
  for (unsigned i = 0; i < numIdentifiers; i++) {
    delete identifiers[i];
  }
  free(identifiers);
  identifiers = 0;
  numIdentifiers = 0;
  identifiersCapacity = 0;

  for (unsigned i = 0; i < numStrings; i++) {
    delete strings[i];
  }
  free(strings);
  strings = 0;
  numStrings = 0;
  stringsCapacity = 0;
}

const int initialCapacity = 64;
const int growthFactor = 2;

Identifier *Lexer::makeIdentifier(UChar *buffer, unsigned int pos)
{
  if (numIdentifiers == identifiersCapacity) {
    identifiersCapacity = (identifiersCapacity == 0) ? initialCapacity : identifiersCapacity *growthFactor;
    identifiers = (KJS::Identifier **)realloc(identifiers, sizeof(KJS::Identifier *) * identifiersCapacity);
  }

  KJS::Identifier *identifier = new KJS::Identifier(buffer, pos);
  identifiers[numIdentifiers++] = identifier;
  return identifier;
}

UString *Lexer::makeUString(UChar *buffer, unsigned int pos)
{
  if (numStrings == stringsCapacity) {
    stringsCapacity = (stringsCapacity == 0) ? initialCapacity : stringsCapacity *growthFactor;
    strings = (UString **)realloc(strings, sizeof(UString *) * stringsCapacity);
  }

  UString *string = new UString(buffer, pos);
  strings[numStrings++] = string;
  return string;
}