Minor Lua fixes. (#3467)

Discovered over on the dev-esp32-idf4 branch.

- Off by one error in loadLFS, leading to slight memory leak and
  potential corruption.

- Insufficient return value check in loadLFS, where uzlib may return
  one of two success conditions, one of which would result in an
  out-of-bounds access and related pain.

- One case of a side effect within a lua_assert(), leading to
  silently broken LFS image handling when compiling without asserts
  enabled, the issue showing up as module names being shuffled around.

- Incorrect encoding of TValues in LFS when 64bit numbers in use.

app/lua/lflash.c

@@ -473,7 +473,7 @@ static int loadLFS (lua_State *L) {
   vfs_lseek(in->fd, 0, VFS_SEEK_SET);
 
   /* Allocate the out buffers */
-  for(i = 0;  i <= WRITE_BLOCKS; i++)
+  for(i = 0;  i < WRITE_BLOCKS; i++)
     out->block[i] = luaM_new(L, outBlock);
 
   /* first inflate pass */
@@ -497,8 +497,9 @@ static int loadLFS (lua_State *L) {
   flashErase(0,(out->flashLen - 1)/FLASH_PAGE_SIZE);
   flashSetPosition(0);
 
-  if ((res = uzlib_inflate(get_byte, put_byte, recall_byte,
-                    in->len, &crc, &in->inflate_state)) != UZLIB_DONE) {
+  res = uzlib_inflate(get_byte, put_byte, recall_byte,
+    in->len, &crc, &in->inflate_state);
+  if (res < 0) { // UZLIB_OK == 0, UZLIB_DONE == 1
     const char *err[] = {"Data_error during decompression",
                          "Chksum_error during decompression",
                          "Dictionary error during decompression",

app/lua53/lundump.c

@@ -145,11 +145,15 @@ static void *Store_(LoadState *S, void *a, int ndx, const void *e, size_t s
 /* These compression maps must match the definitions in lobject.h etc. */
 #  define OFFSET_TSTRING (2*(sizeof(lu_int32)-sizeof(size_t)))
 #  define FMT_TSTRING   "AwwA"
-#  define FMT_TVALUE    "WA"
+#if defined(CONFIG_LUA_NUMBER_INT64) || defined(CONFIG_LUA_NUMBER_DOUBLE) || defined(LUA_NUMBER_64BITS)
+#  define FMT_TVALUE    "www"
+#else
+#  define FMT_TVALUE    "AW"
+#endif
 #  define FMT_PROTO     "AwwwwwwwwwwAAAAAAAA"
 #  define FMT_UPVALUE   "AW"
 #  define FMT_LOCVAR    "Aww"
-#  define FMT_ROTENTRY  "AWA"
+#  define FMT_ROTENTRY  "A" FMT_TVALUE
 #  define FMT_ROTABLE   "AWAA"
 #  define StoreR(S,a, i, v, f) Store_(S, (a), i, &(v), sizeof(v), f)
 #  define Store(S, a, i, v)    StoreR(S, (a), i, v, NULL)
@@ -575,9 +579,10 @@ static void LoadAllProtos (LoadState *S) {
     S->pv[i] = LoadFunction(S, luaF_newproto(L), NULL);
   }
   /* generate the ROTable entries from first N constants; the last is a timestamp */
-  lua_assert(n+1 == LoadInt(S));
+  int nk = LoadInt(S);
+  lua_assert(n+1 == nk);
   ROTable_entry *entry_list = cast(ROTable_entry *, StoreGetPos(S));
-  for (i = 0; i < n; i++) {
+  for (i = 0; i < nk - 1; i++) { // -1 to ignore timestamp
     lu_byte tt_data = LoadByte(S);
     TString *Tname = LoadString2(S, tt_data);
     const char *name = getstr(Tname) + OFFSET_TSTRING;