jsscan.c

Swfdec still is development software, but has also followed a rigid no-crashes-allowed policy. I b

                    if (!AddToTokenBuf(cx, &ts->tokenbuf, (jschar)c))
                        RETURN(TOK_ERROR);
                    c = GetChar(ts);
                } while (JS7_ISDEC(c));
            }
            if (JS_TOLOWER(c) == 'e') {
                if (!AddToTokenBuf(cx, &ts->tokenbuf, (jschar)c))
                    RETURN(TOK_ERROR);
                c = GetChar(ts);
                if (c == '+' || c == '-') {
                    if (!AddToTokenBuf(cx, &ts->tokenbuf, (jschar)c))
                        RETURN(TOK_ERROR);
                    c = GetChar(ts);
                }
                if (!JS7_ISDEC(c)) {
                    js_ReportCompileErrorNumber(cx, ts, NULL, JSREPORT_ERROR,
                                                JSMSG_MISSING_EXPONENT);
                    RETURN(TOK_ERROR);
                }
                do {
                    if (!AddToTokenBuf(cx, &ts->tokenbuf, (jschar)c))
                        RETURN(TOK_ERROR);
                    c = GetChar(ts);
                } while (JS7_ISDEC(c));
            }
        }

        UngetChar(ts, c);
        FINISH_TOKENBUF(&ts->tokenbuf);

        if (radix == 10) {
            if (!js_strtod(cx, ts->tokenbuf.base, &endptr, &dval)) {
                js_ReportCompileErrorNumber(cx, ts, NULL, JSREPORT_ERROR,
                                            JSMSG_OUT_OF_MEMORY);
                RETURN(TOK_ERROR);
            }
        } else {
            if (!js_strtointeger(cx, ts->tokenbuf.base, &endptr, radix, &dval)) {
                js_ReportCompileErrorNumber(cx, ts, NULL, JSREPORT_ERROR,
                                            JSMSG_OUT_OF_MEMORY);
                RETURN(TOK_ERROR);
            }
        }
        tp->t_dval = dval;
        RETURN(TOK_NUMBER);
    }

    if (c == '"' || c == '\'') {
        int32 val, qc = c;

        INIT_TOKENBUF(&ts->tokenbuf);
        while ((c = GetChar(ts)) != qc) {
            if (c == '\n' || c == EOF) {
                UngetChar(ts, c);
                js_ReportCompileErrorNumber(cx, ts, NULL, JSREPORT_ERROR,
                                            JSMSG_UNTERMINATED_STRING);
                RETURN(TOK_ERROR);
            }
            if (c == '\\') {
                switch (c = GetChar(ts)) {
                  case 'b': c = '\b'; break;
                  case 'f': c = '\f'; break;
                  case 'n': c = '\n'; break;
                  case 'r': c = '\r'; break;
                  case 't': c = '\t'; break;
                  case 'v': c = '\v'; break;

                  default:
                    if ('0' <= c && c < '8') {
                        val = JS7_UNDEC(c);
                        c = PeekChar(ts);
                        if ('0' <= c && c < '8') {
                            val = 8 * val + JS7_UNDEC(c);
                            GetChar(ts);
                            c = PeekChar(ts);
                            if ('0' <= c && c < '8') {
                                int32 save = val;
                                val = 8 * val + JS7_UNDEC(c);
                                if (val <= 0377)
                                    GetChar(ts);
                                else
                                    val = save;
                            }
                        }
                        c = (jschar)val;
                    } else if (c == 'u') {
                        jschar cp[4];
                        if (PeekChars(ts, 4, cp) &&
                            JS7_ISHEX(cp[0]) && JS7_ISHEX(cp[1]) &&
                            JS7_ISHEX(cp[2]) && JS7_ISHEX(cp[3])) {
                            c = (((((JS7_UNHEX(cp[0]) << 4)
                                    + JS7_UNHEX(cp[1])) << 4)
                                  + JS7_UNHEX(cp[2])) << 4)
                                + JS7_UNHEX(cp[3]);
                            SkipChars(ts, 4);
                        }
                    } else if (c == 'x') {
                        jschar cp[2];
                        if (PeekChars(ts, 2, cp) &&
                            JS7_ISHEX(cp[0]) && JS7_ISHEX(cp[1])) {
                            c = (JS7_UNHEX(cp[0]) << 4) + JS7_UNHEX(cp[1]);
                            SkipChars(ts, 2);
                        }
                    } else if (c == '\n' && JSVERSION_IS_ECMA(cx->version)) {
                        /* ECMA follows C by removing escaped newlines. */
                        continue;
                    }
                    break;
                }
            }
            if (!AddToTokenBuf(cx, &ts->tokenbuf, (jschar)c))
                RETURN(TOK_ERROR);
        }
        FINISH_TOKENBUF(&ts->tokenbuf);
        atom = js_AtomizeChars(cx,
                               ts->tokenbuf.base,
                               TOKEN_LENGTH(&ts->tokenbuf),
                               0);
        if (!atom)
            RETURN(TOK_ERROR);
        tp->pos.end.lineno = (uint16)ts->lineno;
        tp->t_op = JSOP_STRING;
        tp->t_atom = atom;
        RETURN(TOK_STRING);
    }

    switch (c) {
      case '\n': 
        c = TOK_EOL; 
        break;

      case ';': c = TOK_SEMI; break;
      case '.': c = TOK_DOT; break;
      case '[': c = TOK_LB; break;
      case ']': c = TOK_RB; break;
      case '{': c = TOK_LC; break;
      case '}': c = TOK_RC; break;
      case '(': c = TOK_LP; break;
      case ')': c = TOK_RP; break;
      case ',': c = TOK_COMMA; break;
      case '?': c = TOK_HOOK; break;

      case ':':
        /*
         * Default so compiler can modify to JSOP_GETTER if 'p getter: v' in an
         * object initializer, likewise for setter.
         */
        tp->t_op = JSOP_NOP;
        c = TOK_COLON;
        break;

      case '|':
        if (MatchChar(ts, c)) {
            c = TOK_OR;
        } else if (MatchChar(ts, '=')) {
            tp->t_op = JSOP_BITOR;
            c = TOK_ASSIGN;
        } else {
            c = TOK_BITOR;
        }
        break;

      case '^':
        if (MatchChar(ts, '=')) {
            tp->t_op = JSOP_BITXOR;
            c = TOK_ASSIGN;
        } else {
            c = TOK_BITXOR;
        }
        break;

      case '&':
        if (MatchChar(ts, c)) {
            c = TOK_AND;
        } else if (MatchChar(ts, '=')) {
            tp->t_op = JSOP_BITAND;
            c = TOK_ASSIGN;
        } else {
            c = TOK_BITAND;
        }
        break;

      case '=':
        if (MatchChar(ts, c)) {
#if JS_HAS_TRIPLE_EQOPS
            tp->t_op = MatchChar(ts, c) ? JSOP_NEW_EQ : (JSOp)cx->jsop_eq;
#else
            tp->t_op = cx->jsop_eq;
#endif
            c = TOK_EQOP;
        } else {
            tp->t_op = JSOP_NOP;
            c = TOK_ASSIGN;
        }
        break;

      case '!':
        if (MatchChar(ts, '=')) {
#if JS_HAS_TRIPLE_EQOPS
            tp->t_op = MatchChar(ts, '=') ? JSOP_NEW_NE : (JSOp)cx->jsop_ne;
#else
            tp->t_op = cx->jsop_ne;
#endif
            c = TOK_EQOP;
        } else {
            tp->t_op = JSOP_NOT;
            c = TOK_UNARYOP;
        }
        break;

      case '<':
        /* NB: treat HTML begin-comment as comment-till-end-of-line */
        if (MatchChar(ts, '!')) {
            if (MatchChar(ts, '-')) {
                if (MatchChar(ts, '-'))
                    goto skipline;
                UngetChar(ts, '-');
            }
            UngetChar(ts, '!');
        }
        if (MatchChar(ts, c)) {
            tp->t_op = JSOP_LSH;
            c = MatchChar(ts, '=') ? TOK_ASSIGN : TOK_SHOP;
        } else {
            tp->t_op = MatchChar(ts, '=') ? JSOP_LE : JSOP_LT;
            c = TOK_RELOP;
        }
        break;

      case '>':
        if (MatchChar(ts, c)) {
            tp->t_op = MatchChar(ts, c) ? JSOP_URSH : JSOP_RSH;
            c = MatchChar(ts, '=') ? TOK_ASSIGN : TOK_SHOP;
        } else {
            tp->t_op = MatchChar(ts, '=') ? JSOP_GE : JSOP_GT;
            c = TOK_RELOP;
        }
        break;

      case '*':
        tp->t_op = JSOP_MUL;
        c = MatchChar(ts, '=') ? TOK_ASSIGN : TOK_STAR;
        break;

      case '/':
        if (MatchChar(ts, '/')) {
skipline:
            while ((c = GetChar(ts)) != EOF && c != '\n')
                /* skip to end of line */;
            UngetChar(ts, c);
            goto retry;
        }
        if (MatchChar(ts, '*')) {
            while ((c = GetChar(ts)) != EOF &&
                   !(c == '*' && MatchChar(ts, '/'))) {
                /* Ignore all characters until comment close. */
            }
            if (c == EOF) {
                js_ReportCompileErrorNumber(cx, ts, NULL, JSREPORT_ERROR,
                                            JSMSG_UNTERMINATED_COMMENT);
                RETURN(TOK_ERROR);
            }
            goto retry;
        }

#if JS_HAS_REGEXPS
        if (ts->flags & TSF_REGEXP) {
            JSObject *obj;
            uintN flags;

            INIT_TOKENBUF(&ts->tokenbuf);
            while ((c = GetChar(ts)) != '/') {
                if (c == '\n' || c == EOF) {
                    UngetChar(ts, c);
                    js_ReportCompileErrorNumber(cx, ts, NULL, JSREPORT_ERROR,
                                                JSMSG_UNTERMINATED_REGEXP);
                    RETURN(TOK_ERROR);
                }
                if (c == '\\') {
                    if (!AddToTokenBuf(cx, &ts->tokenbuf, (jschar)c))
                        RETURN(TOK_ERROR);
                    c = GetChar(ts);
                }
                if (!AddToTokenBuf(cx, &ts->tokenbuf, (jschar)c))
                    RETURN(TOK_ERROR);
            }
            FINISH_TOKENBUF(&ts->tokenbuf);
            for (flags = 0; ; ) {
                if (MatchChar(ts, 'g'))
                    flags |= JSREG_GLOB;
                else if (MatchChar(ts, 'i'))
                    flags |= JSREG_FOLD;
                else if (MatchChar(ts, 'm'))
                    flags |= JSREG_MULTILINE;
                else
                    break;
            }
            c = PeekChar(ts);
            if (JS7_ISLET(c)) {
                tp->ptr = ts->linebuf.ptr - 1;
                js_ReportCompileErrorNumber(cx, ts, NULL, JSREPORT_ERROR,
                                            JSMSG_BAD_REGEXP_FLAG);
                (void) GetChar(ts);
                RETURN(TOK_ERROR);
            }
            obj = js_NewRegExpObject(cx, ts,
                                     ts->tokenbuf.base,
                                     TOKEN_LENGTH(&ts->tokenbuf),
                                     flags);
            if (!obj)
                RETURN(TOK_ERROR);
            atom = js_AtomizeObject(cx, obj, 0);
            if (!atom)
                RETURN(TOK_ERROR);
            tp->t_op = JSOP_OBJECT;
            tp->t_atom = atom;
            RETURN(TOK_OBJECT);
        }
#endif /* JS_HAS_REGEXPS */

        tp->t_op = JSOP_DIV;
        c = MatchChar(ts, '=') ? TOK_ASSIGN : TOK_DIVOP;
        break;

      case '%':
        tp->t_op = JSOP_MOD;
        c = MatchChar(ts, '=') ? TOK_ASSIGN : TOK_DIVOP;
        break;

      case '~':
        tp->t_op = JSOP_BITNOT;
        c = TOK_UNARYOP;
        break;

      case '+':
        if (MatchChar(ts, '=')) {
            tp->t_op = JSOP_ADD;
            c = TOK_ASSIGN;
        } else if (MatchChar(ts, c)) {
            c = TOK_INC;
        } else {
            tp->t_op = JSOP_POS;
            c = TOK_PLUS;
        }
        break;

      case '-':
        if (MatchChar(ts, '=')) {
            tp->t_op = JSOP_SUB;
            c = TOK_ASSIGN;
        } else if (MatchChar(ts, c)) {
            if (PeekChar(ts) == '>' && !(ts->flags & TSF_DIRTYLINE))
                goto skipline;
            c = TOK_DEC;
        } else {
            tp->t_op = JSOP_NEG;
            c = TOK_MINUS;
        }
        ts->flags |= TSF_DIRTYLINE;
        break;

#if JS_HAS_SHARP_VARS
      case '#':
      {
        uint32 n;

        c = GetChar(ts);
        if (!JS7_ISDEC(c)) {
            UngetChar(ts, c);
            goto badchar;
        }
        n = (uint32)JS7_UNDEC(c);
        for (;;) {
            c = GetChar(ts);
            if (!JS7_ISDEC(c))
                break;
            n = 10 * n + JS7_UNDEC(c);
            if (n >= ATOM_INDEX_LIMIT) {
                js_ReportCompileErrorNumber(cx, ts, NULL, JSREPORT_ERROR,
                                            JSMSG_SHARPVAR_TOO_BIG);
                RETURN(TOK_ERROR);
            }
        }
        tp->t_dval = (jsdouble) n;
        if (JS_HAS_STRICT_OPTION(cx) &&
            (c == '=' || c == '#')) {
            char buf[20];
            JS_snprintf(buf, sizeof buf, "#%u%c", n, c);
            if (!js_ReportCompileErrorNumber(cx, ts, NULL,
                                             JSREPORT_WARNING |
                                             JSREPORT_STRICT,
                                             JSMSG_DEPRECATED_USAGE,
                                             buf)) {
                RETURN(TOK_ERROR);
            }
        }
        if (c == '=')
            RETURN(TOK_DEFSHARP);
        if (c == '#')
            RETURN(TOK_USESHARP);
        goto badchar;
      }

      badchar:
#endif /* JS_HAS_SHARP_VARS */

      default:
        js_ReportCompileErrorNumber(cx, ts, NULL, JSREPORT_ERROR,
                                    JSMSG_ILLEGAL_CHARACTER);
        RETURN(TOK_ERROR);
    }

    JS_ASSERT(c < TOK_LIMIT);
    RETURN((JSTokenType)c);

#undef INIT_TOKENBUF
#undef FINISH_TOKENBUF
#undef TOKEN_LENGTH
#undef RETURN
}

void
js_UngetToken(JSTokenStream *ts)
{
    JS_ASSERT(ts->lookahead < NTOKENS_MASK);
    if (ts->flags & TSF_ERROR)
        return;
    ts->lookahead++;
    ts->cursor = (ts->cursor - 1) & NTOKENS_MASK;
}

JSBool
js_MatchToken(JSContext *cx, JSTokenStream *ts, JSTokenType tt)
{
    if (js_GetToken(cx, ts) == tt)
        return JS_TRUE;
    js_UngetToken(ts);
    return JS_FALSE;
}