Function luaS_new

3rd/lua-5.4.3/src/lstring.c:241–255

** Create or reuse a zero-terminated string, first checking in the ** cache (using the string address as a key). The cache can contain ** only zero-terminated strings, so it is safe to use 'strcmp' to ** check hits. */

** check hits.
*/
TString *luaS_new (lua_State *L, const char *str) {
  unsigned int i = point2uint(str) % STRCACHE_N;  /* hash */
  int j;
  TString **p = G(L)->strcache[i];
  for (j = 0; j < STRCACHE_M; j++) {
    if (strcmp(str, getstr(p[j])) == 0)  /* hit? */
      return p[j];  /* that is it */
  }
  /* normal route */
  for (j = STRCACHE_M - 1; j > 0; j--)
    p[j] = p[j - 1];  /* move out last element */
  /* new element is first in the list */
  p[0] = luaS_newlstr(L, str, strlen(str));
  return p[0];
}


Udata *luaS_newudata (lua_State *L, size_t s, int nuvalue) {