Function StringToMap

src/kv/RocksDBStore.cc:251–328

this function is a modification of rocksdb's StringToMap: 1) accepts ' \n ; as separators 2) leaves compound options with enclosing { and }

// 1) accepts ' \n ; as separators
// 2) leaves compound options with enclosing { and }
rocksdb::Status StringToMap(const std::string& opts_str,
			    std::unordered_map<std::string, std::string>* opts_map)
{
  using rocksdb::Status;
  using rocksdb::trim;
  assert(opts_map);
  // Example:
  //   opts_str = "write_buffer_size=1024;max_write_buffer_number=2;"
  //              "nested_opt={opt1=1;opt2=2};max_bytes_for_level_base=100"
  size_t pos = 0;
  std::string opts = trim(opts_str);
  while (pos < opts.size()) {
    size_t eq_pos = opts.find('=', pos);
    if (eq_pos == std::string::npos) {
      return Status::InvalidArgument("Mismatched key value pair, '=' expected");
    }
    std::string key = trim(opts.substr(pos, eq_pos - pos));
    if (key.empty()) {
      return Status::InvalidArgument("Empty key found");
    }

    // skip space after '=' and look for '{' for possible nested options
    pos = eq_pos + 1;
    while (pos < opts.size() && isspace(opts[pos])) {
      ++pos;
    }
    // Empty value at the end
    if (pos >= opts.size()) {
      (*opts_map)[key] = "";
      break;
    }
    if (opts[pos] == '{') {
      int count = 1;
      size_t brace_pos = pos + 1;
      while (brace_pos < opts.size()) {
        if (opts[brace_pos] == '{') {
          ++count;
        } else if (opts[brace_pos] == '}') {
          --count;
          if (count == 0) {
            break;
          }
        }
        ++brace_pos;
      }
      // found the matching closing brace
      if (count == 0) {
	//include both '{' and '}'
        (*opts_map)[key] = trim(opts.substr(pos, brace_pos - pos + 1));
        // skip all whitespace and move to the next ';,'
        // brace_pos points to the matching '}'
        pos = brace_pos + 1;
        while (pos < opts.size() && isspace(opts[pos])) {
          ++pos;
        }
        if (pos < opts.size() && opts[pos] != ';' && opts[pos] != ',') {
          return Status::InvalidArgument(
              "Unexpected chars after nested options");