static JSONCPP_STRING valueToQuotedStringN(const char* value, unsigned length) {
if (value == NULL)
return "";
// Not sure how to handle unicode...
if (strnpbrk(value, "\"\\\b\f\n\r\t", length) == NULL &&
!containsControlCharacter0(value, length))
return JSONCPP_STRING("\"") + value + "\"";
// We have to walk value and escape any special characters.
// Appending to JSONCPP_STRING is not efficient, but this should be rare.
// (Note: forward slashes are *not* rare, but I am not escaping them.)
JSONCPP_STRING::size_type maxsize =
length * 2 + 3; // allescaped+quotes+NULL
JSONCPP_STRING result;
result.reserve(maxsize); // to avoid lots of mallocs
result += "\"";
char const* end = value + length;
for (const char* c = value; c != end; ++c) {
switch (*c) {
case '\"':
result += "\\\"";
break;
case '\\':
result += "\\\\";
break;
case '\b':
result += "\\b";
break;
case '\f':
result += "\\f";
break;
case '\n':
result += "\\n";
break;
case '\r':
result += "\\r";
break;
case '\t':
result += "\\t";
break;
// case '/':
// Even though \/ is considered a legal escape in JSON, a bare
// slash is also legal, so I see no reason to escape it.
// (I hope I am not misunderstanding something.)
// blep notes: actually escaping \/ may be useful in javascript to avoid </
// sequence.
// Should add a flag to allow this compatibility mode and prevent this
// sequence from occurring.
default:
if ((isControlCharacter(*c)) || (*c == 0)) {
JSONCPP_OSTRINGSTREAM oss;
oss << "\\u" << std::hex << std::uppercase << std::setfill('0')
<< std::setw(4) << static_cast<int>(*c);
result += oss.str();
} else {
result += *c;
}
break;
}
}
result += "\"";
return result;
}
