Function loadString

third-party/lua-5.5.0/src/lundump.c:145–184

** Load a nullable string into slot 'sl' from prototype 'p'. The ** assignment to the slot and the barrier must be performed before any ** possible GC activity, to anchor the string. (Both 'loadVector' and ** 'luaH_setint' can call the GC.) */

** 'luaH_setint' can call the GC.)
*/
static void loadString (LoadState *S, Proto *p, TString **sl) {
  lua_State *L = S->L;
  TString *ts;
  TValue sv;
  size_t size = loadSize(S);
  if (size == 0) {  /* previously saved string? */
    lua_Unsigned idx = loadVarint(S, LUA_MAXUNSIGNED);  /* get its index */
    TValue stv;
    if (idx == 0) {  /* no string? */
      lua_assert(*sl == NULL);  /* must be prefilled */
      return;
    }
    if (novariant(luaH_getint(S->h, l_castU2S(idx), &stv)) != LUA_TSTRING)
      error(S, "invalid string index");
    *sl = ts = tsvalue(&stv);  /* get its value */
    luaC_objbarrier(L, p, ts);
    return;  /* do not save it again */
  }
  else if ((size -= 1) <= LUAI_MAXSHORTLEN) {  /* short string? */
    char buff[LUAI_MAXSHORTLEN + 1];  /* extra space for '\0' */
    loadVector(S, buff, size + 1);  /* load string into buffer */
    *sl = ts = luaS_newlstr(L, buff, size);  /* create string */
    luaC_objbarrier(L, p, ts);
  }
  else if (S->fixed) {  /* for a fixed buffer, use a fixed string */
    const char *s = getaddr(S, size + 1, char);  /* get content address */
    *sl = ts = luaS_newextlstr(L, s, size, NULL, NULL);
    luaC_objbarrier(L, p, ts);
  }
  else {  /* create internal copy */
    *sl = ts = luaS_createlngstrobj(L, size);  /* create string */
    luaC_objbarrier(L, p, ts);
    loadVector(S, getlngstr(ts), size + 1);  /* load directly in final place */
  }
  /* add string to list of saved strings */
  S->nstr++;
  setsvalue(L, &sv, ts);
  luaH_setint(L, S->h, l_castU2S(S->nstr), &sv);
  luaC_objbarrierback(L, obj2gco(S->h), ts);
}


static void loadCode (LoadState *S, Proto *f) {