const char *sv_names[] = {
  "NULL",
  "IV",
  "NV",
  "RV",
  "PV",
  "PVIV",
  "PVNV",
  "PVMG",
  "PVBM",
  "PVLV",
  "PVAV",
  "PVHV",
  "PVCV",
  "PVGV",
  "PVFM",
  "PVIO"
};
const size_t sv_names_len = sizeof(sv_names) / sizeof(char *);