Function strnpbrk

src/share/jsoncpp/jsoncpp.cpp:4321–4334

https://github.com/upcaste/upcaste/blob/master/src/upcore/src/cstring/strnpbrk.cpp

// https://github.com/upcaste/upcaste/blob/master/src/upcore/src/cstring/strnpbrk.cpp
static char const* strnpbrk(char const* s, char const* accept, size_t n) {
  assert((s || !n) && accept);

  char const* const end = s + n;
  for (char const* cur = s; cur < end; ++cur) {
    int const c = *cur;
    for (char const* a = accept; *a; ++a) {
      if (*a == c) {
        return cur;
      }
    }
  }
  return NULL;
}
static JSONCPP_STRING valueToQuotedStringN(const char* value, unsigned length) {
  if (value == NULL)
    return "";