Function CountOpenFds

be/src/kudu/util/test_util.cc:386–438

}

int CountOpenFds(Env* env, const string& path_pattern) {
  static const char* kProcSelfFd =
#if defined(__APPLE__)
    "/dev/fd";
#else
    "/proc/self/fd";
#endif // defined(__APPLE__)
  faststring path_buf;
  vector<string> children;
  CHECK_OK(env->GetChildren(kProcSelfFd, &children));
  int num_fds = 0;
  for (const auto& c : children) {
    // Skip '.' and '..'.
    if (c == "." || c == "..") {
      continue;
    }
    int32_t fd;
    CHECK(safe_strto32(c, &fd)) << "Unexpected file in fd list: " << c;
#ifdef __APPLE__
    path_buf.resize(MAXPATHLEN);
    if (fcntl(fd, F_GETPATH, path_buf.data()) != 0) {
      if (errno == EBADF) {
        // The file was closed while we were looping. This is likely the
        // actual file descriptor used for opening /proc/fd itself.
        continue;
      }
      PLOG(FATAL) << "Unknown error in fcntl(F_GETPATH): " << fd;
    }
    char* buf_data = reinterpret_cast<char*>(path_buf.data());
    path_buf.resize(strlen(buf_data));
#else
    path_buf.resize(PATH_MAX);
    char* buf_data = reinterpret_cast<char*>(path_buf.data());
    auto proc_file = JoinPathSegments(kProcSelfFd, c);
    int path_len = readlink(proc_file.c_str(), buf_data, path_buf.size());
    if (path_len < 0) {
      if (errno == ENOENT) {
        // The file was closed while we were looping. This is likely the
        // actual file descriptor used for opening /proc/fd itself.
        continue;
      }
      PLOG(FATAL) << "Unknown error in readlink: " << proc_file;
    }
    path_buf.resize(path_len);
#endif
    if (!MatchPattern(path_buf.ToString(), path_pattern)) {
      continue;
    }
    num_fds++;
  }

  return num_fds;
}

namespace {
const vector<string> kWildcard = { "0.0.0.0" };