static bool match_pattern_helper()

in mcrouter/route.cpp [18:58]

• 34 lines of code
• 13 McCabe index (conditional complexity)

static bool match_pattern_helper(
    const char* pi,
    const char* pend,
    const char* ri,
    const char* rend) {
  while (pi != pend) {
    if (ri == rend) {
      return false;
    } else if (*pi == '*') {
      /* Swallow multiple stars */
      do {
        ++pi;
      } while (pi != pend && *pi == '*');

      if (pi == pend) {
        /* Terminating star matches any string not containing slashes */
        return memchr(ri, '/', rend - ri) == nullptr;
      } else if (*pi == '/') {
        /* start + slash: advance ri to the next slash */
        ri = static_cast<const char*>(memchr(ri, '/', rend - ri));
        if (ri == nullptr) {
          return false;
        }
      } else {
        /* Try to match '*' with every prefix,
           recursively try to match the remainder */
        while (ri != rend && *ri != '/') {
          if (match_pattern_helper(pi, pend, ri, rend)) {
            return true;
          }
          ++ri;
        }
        return false;
      }
    } else if (*pi++ != *ri++) {
      return false;
    }
  }

  return ri == rend;
}