示例#1
0
文件: Eval.cpp 项目: martasect/gecko
static bool
EvalStringMightBeJSON(const mozilla::Range<const CharT> chars)
{
    // If the eval string starts with '(' or '[' and ends with ')' or ']', it may be JSON.
    // Try the JSON parser first because it's much faster.  If the eval string
    // isn't JSON, JSON parsing will probably fail quickly, so little time
    // will be lost.
    size_t length = chars.length();
    if (length > 2 &&
        ((chars[0] == '[' && chars[length - 1] == ']') ||
         (chars[0] == '(' && chars[length - 1] == ')')))
    {
        // Remarkably, JavaScript syntax is not a superset of JSON syntax:
        // strings in JavaScript cannot contain the Unicode line and paragraph
        // terminator characters U+2028 and U+2029, but strings in JSON can.
        // Rather than force the JSON parser to handle this quirk when used by
        // eval, we simply don't use the JSON parser when either character
        // appears in the provided string.  See bug 657367.
        if (sizeof(CharT) > 1) {
            for (RangedPtr<const CharT> cp = chars.start() + 1, end = chars.end() - 1;
                 cp < end;
                 cp++)
            {
                char16_t c = *cp;
                if (c == 0x2028 || c == 0x2029)
                    return false;
            }
        }

        return true;
    }
    return false;
}
示例#2
0
static bool
ArgsAndBodySubstring(mozilla::Range<const CharT> chars, size_t *outOffset, size_t *outLen)
{
    const CharT *const start = chars.start().get();
    const CharT *const end = chars.end().get();
    const CharT *s = start;

    uint8_t parenChomp = 0;
    if (s[0] == '(') {
        s++;
        parenChomp = 1;
    }

    /* Try to jump "function" keyword. */
    s = js_strchr_limit(s, ' ', end);
    if (!s)
        return false;

    /*
     * Jump over the function's name: it can't be encoded as part
     * of an ECMA getter or setter.
     */
    s = js_strchr_limit(s, '(', end);
    if (!s)
        return false;

    if (*s == ' ')
        s++;

    *outOffset = s - start;
    *outLen = end - s - parenChomp;
    MOZ_ASSERT(*outOffset + *outLen <= chars.length());
    return true;
}