_ Git - ldk-java/blob - gen_type_mapping.py

   1 from bindingstypes import ConvInfo
   2
   3 class TypeMappingGenerator:
   4
   5     def __init__(self, java_c_types, consts, opaque_structs, clone_fns, unitary_enums, trait_structs, complex_enums, result_types, tuple_types):
   6         # trick our way around circular imports
   7         self.java_c_types = java_c_types
   8         self.consts = consts
   9         self.opaque_structs = opaque_structs
  10         self.clone_fns = clone_fns
  11         self.unitary_enums = unitary_enums
  12         self.trait_structs = trait_structs
  13         self.complex_enums = complex_enums
  14         self.result_types = result_types
  15         self.tuple_types = tuple_types
  16
  17     def map_type(self, fn_arg, print_void, ret_arr_len, is_free, holds_ref):
  18         ty_info = self.java_c_types(fn_arg, ret_arr_len)
  19         mapped_info = self.map_type_with_info(ty_info, print_void, ret_arr_len, is_free, holds_ref, False)
  20         return mapped_info
  21
  22     def map_nullable_type(self, fn_arg, print_void, ret_arr_len, is_free, holds_ref):
  23         ty_info = self.java_c_types(fn_arg, ret_arr_len)
  24         mapped_info = self.map_type_with_info(ty_info, print_void, ret_arr_len, is_free, holds_ref, True)
  25         return mapped_info
  26
  27     def map_type_with_info(self, ty_info, print_void, ret_arr_len, is_free, holds_ref, is_nullable):
  28         mapped_info = self._do_map_type_with_info(ty_info, print_void, ret_arr_len, is_free, holds_ref, is_nullable)
  29         if is_nullable:
  30             mapped_info.nullable = True
  31         return mapped_info
  32
  33     def _do_map_type_with_info(self, ty_info, print_void, ret_arr_len, is_free, holds_ref, is_nullable):
  34         if ty_info.c_ty == "void":
  35             if not print_void:
  36                 return ConvInfo(ty_info = ty_info, arg_name = ty_info.var_name,
  37                     arg_conv = None, arg_conv_name = None, arg_conv_cleanup = None,
  38                     ret_conv = None, ret_conv_name = None, to_hu_conv = None, to_hu_conv_name = None, from_hu_conv = None)
  39         if ty_info.c_ty.endswith("Array"):
  40             arr_len = ty_info.arr_len
  41             if arr_len is not None:
  42                 arr_name = ty_info.var_name
  43             else:
  44                 arr_name = "ret"
  45                 arr_len = ret_arr_len
  46             if ty_info.c_ty == "int8_tArray":
  47                 (set_pfx, set_sfx) = self.consts.set_native_arr_contents(arr_name + "_arr", arr_len, ty_info)
  48                 ret_conv = ("int8_tArray " + arr_name + "_arr = " + self.consts.create_native_arr_call(arr_len, ty_info) + ";\n" + set_pfx, "")
  49                 arg_conv_cleanup = None
  50                 from_hu_conv = None
  51                 if not arr_len.isdigit():
  52                     arg_conv = ty_info.rust_obj + " " + arr_name + "_ref;\n"
  53                     arg_conv = arg_conv + arr_name + "_ref." + arr_len + " = " +  self.consts.get_native_arr_len_call[0] + arr_name + self.consts.get_native_arr_len_call[1] + ";\n"
  54                     if (not ty_info.is_ptr or not holds_ref) and ty_info.rust_obj != "LDKu8slice":
  55                         arg_conv = arg_conv + arr_name + "_ref." + ty_info.arr_access + " = MALLOC(" + arr_name + "_ref." + arr_len + ", \"" + ty_info.rust_obj + " Bytes\");\n"
  56                         arg_conv = arg_conv + self.consts.get_native_arr_contents(arr_name, arr_name + "_ref." + ty_info.arr_access, arr_name + "_ref." + arr_len, ty_info, True) + ";"
  57                     else:
  58                         arg_conv = arg_conv + arr_name + "_ref." + ty_info.arr_access + " = " + self.consts.get_native_arr_contents(arr_name, "NO_DEST", arr_name + "_ref." + arr_len, ty_info, False) + ";"
  59                         arg_conv_cleanup = self.consts.cleanup_native_arr_ref_contents(arr_name, arr_name + "_ref." + ty_info.arr_access, arr_name + "_ref." + arr_len, ty_info)
  60                     if ty_info.rust_obj == "LDKTransaction":
  61                         arg_conv = arg_conv + "\n" + arr_name + "_ref.data_is_owned = " + str(holds_ref).lower() + ";"
  62                     ret_conv = (ty_info.rust_obj + " " + arr_name + "_var = ", "")
  63                     ret_conv = (ret_conv[0], ";\nint8_tArray " + arr_name + "_arr = " + self.consts.create_native_arr_call(arr_name + "_var." + arr_len, ty_info) + ";\n")
  64                     (pfx, sfx) = self.consts.set_native_arr_contents(arr_name + "_arr", arr_name + "_var." + arr_len, ty_info)
  65                     ret_conv = (ret_conv[0], ret_conv[1] + pfx + arr_name + "_var." + ty_info.arr_access + sfx + ";")
  66                     if not holds_ref and ty_info.rust_obj != "LDKu8slice":
  67                         ret_conv = (ret_conv[0], ret_conv[1] + "\n" + ty_info.rust_obj.replace("LDK", "") + "_free(" + arr_name + "_var);")
  68                 elif ty_info.rust_obj is not None:
  69                     arg_conv = ty_info.rust_obj + " " + arr_name + "_ref;\n"
  70                     arg_conv = arg_conv + "CHECK(" + self.consts.get_native_arr_len_call[0] + arr_name + self.consts.get_native_arr_len_call[1] + " == " + arr_len + ");\n"
  71                     arg_conv = arg_conv + self.consts.get_native_arr_contents(arr_name, arr_name + "_ref." + ty_info.arr_access, arr_len, ty_info, True) + ";"
  72                     ret_conv = (ret_conv[0], "." + ty_info.arr_access + set_sfx + ";")
  73                     from_hu_conv = ("InternalUtils.check_arr_len(" + arr_name + ", " + arr_len + ")", "")
  74                 else:
  75                     arg_conv = "unsigned char " + arr_name + "_arr[" + arr_len + "];\n"
  76                     arg_conv = arg_conv + "CHECK(" + self.consts.get_native_arr_len_call[0] + arr_name + self.consts.get_native_arr_len_call[1] + " == " + arr_len + ");\n"
  77                     arg_conv = arg_conv + self.consts.get_native_arr_contents(arr_name, arr_name + "_arr", arr_len, ty_info, True) + ";\n"
  78                     arg_conv = arg_conv + "unsigned char (*" + arr_name + "_ref)[" + arr_len + "] = &" + arr_name + "_arr;"
  79                     ret_conv = (ret_conv[0] + "*", set_sfx + ";")
  80                     from_hu_conv = ("InternalUtils.check_arr_len(" + arr_name + ", " + arr_len + ")", "")
  81                 return ConvInfo(ty_info = ty_info, arg_name = ty_info.var_name,
  82                     arg_conv = arg_conv, arg_conv_name = arr_name + "_ref", arg_conv_cleanup = arg_conv_cleanup,
  83                     ret_conv = ret_conv, ret_conv_name = arr_name + "_arr", to_hu_conv = None, to_hu_conv_name = None,
  84                     from_hu_conv = from_hu_conv)
  85             else:
  86                 assert not arr_len.isdigit() # fixed length arrays not implemented
  87                 assert ty_info.java_ty[len(ty_info.java_ty) - 2:] == "[]"
  88                 if arr_name == "":
  89                     arr_name = "ret"
  90                 conv_name = arr_name + "_conv_" + str(len(ty_info.java_hu_ty))
  91                 idxc = chr(ord('a') + (len(ty_info.java_hu_ty) % 26))
  92                 ty_info.subty.var_name = conv_name
  93                 #XXX: We'd really prefer to only ever set to False, avoiding lots of clone, but need smarter free logic
  94                 #if ty_info.is_ptr or holds_ref:
  95                 #    ty_info.subty.requires_clone = False
  96                 ty_info.subty.requires_clone = not ty_info.is_ptr or not holds_ref
  97                 if not ty_info.subty.is_native_primitive and ty_info.subty.rust_obj == "LDKChannelMonitor":
  98                     # We take a Vec of references to ChannelMonitors as input to ChannelManagerReadArgs, if we clone them,
  99                     # we end up freeing the clones after creating the ChannelManagerReadArgs before calling the read
 100                     # function itself, resulting in a segfault. Thus, we manually check and ensure we don't clone for
 101                     # ChannelMonitors inside of vecs.
 102                     ty_info.subty.requires_clone = False
 103                 subty = self.map_type_with_info(ty_info.subty, False, None, is_free, holds_ref, False)
 104                 arg_conv = ty_info.rust_obj + " " + arr_name + "_constr;\n"
 105                 pf = ""
 106                 if ty_info.is_ptr:
 107                     pf = "\t"
 108                     arg_conv += ty_info.rust_obj + " *" + arr_name + "_ptr = NULL;\n"
 109                     arg_conv += "if (" + self.consts.is_arr_some_check[0] + arr_name + self.consts.is_arr_some_check[1] + ") {\n"
 110                 arg_conv += pf + arr_name + "_constr." + arr_len + " = " + self.consts.get_native_arr_len_call[0] + arr_name + self.consts.get_native_arr_len_call[1] + ";\n"
 111                 arg_conv += pf + "if (" + arr_name + "_constr." + arr_len + " > 0)\n"
 112                 if subty.is_native_primitive:
 113                     szof = subty.c_ty
 114                 else:
 115                     szof = subty.rust_obj
 116                 arg_conv += pf + "\t" + arr_name + "_constr." + ty_info.arr_access + " = MALLOC(" + arr_name + "_constr." + arr_len + " * sizeof(" + szof + "), \"" + ty_info.rust_obj + " Elements\");\n"
 117                 arg_conv += pf + "else\n"
 118                 arg_conv += pf + "\t" + arr_name + "_constr." + ty_info.arr_access + " = NULL;\n"
 119                 get_arr = self.consts.get_native_arr_contents(arr_name, "NO_DEST", arr_name + "_constr." + arr_len, ty_info, False)
 120                 if get_arr != None:
 121                     arg_conv += pf + subty.c_ty + "* " + arr_name + "_vals = " + get_arr + ";\n"
 122                 arg_conv += pf + "for (size_t " + idxc + " = 0; " + idxc + " < " + arr_name + "_constr." + arr_len + "; " + idxc + "++) {\n"
 123                 if get_arr != None:
 124                     arg_conv += pf + "\t" + subty.c_ty + " " + conv_name + " = " + arr_name + "_vals[" + idxc + "];"
 125                     if subty.arg_conv is not None:
 126                         arg_conv += "\n\t" + pf + subty.arg_conv.replace("\n", "\n\t" + pf)
 127                 else:
 128                     arg_conv += pf + "\t" + subty.c_ty + " " + conv_name + " = " + self.consts.get_native_arr_elem(arr_name, idxc, ty_info) + ";\n"
 129                     arg_conv += pf + "\t" + subty.arg_conv.replace("\n", "\n\t" + pf)
 130                 arg_conv += "\n\t" + pf + arr_name + "_constr." + ty_info.arr_access + "[" + idxc + "] = " + subty.arg_conv_name + ";\n" + pf + "}"
 131                 if get_arr != None:
 132                     cleanup = self.consts.cleanup_native_arr_ref_contents(arr_name, arr_name + "_vals", arr_name + "_constr." + arr_len, ty_info)
 133                     if cleanup is not None:
 134                         arg_conv += "\n" + pf + cleanup + ";"
 135                 if ty_info.is_ptr:
 136                     arg_conv_name = arr_name + "_ptr"
 137                 else:
 138                     arg_conv_name = arr_name + "_constr"
 139                 arg_conv_cleanup = None
 140                 if ty_info.is_ptr:
 141                     arg_conv_cleanup = "if (" + arr_name + "_ptr != NULL) { FREE(" + arr_name + "_constr." + ty_info.arr_access + "); }"
 142                 if ty_info.is_ptr:
 143                     arg_conv += "\n\t" + arr_name + "_ptr = &" + arr_name + "_constr;\n}"
 144
 145                 if is_nullable:
 146                     ret_conv = (ty_info.rust_obj + " *" + arr_name + "_var_ptr = ", "")
 147                 else:
 148                     ret_conv = (ty_info.rust_obj + " " + arr_name + "_var = ", "")
 149                 if subty.ret_conv is None:
 150                     ret_conv = ("DUMMY", "DUMMY")
 151                 else:
 152                     ret_conv = (ret_conv[0], ";\n" + ty_info.c_ty + " " + arr_name + "_arr = NULL;\n")
 153                     indent = ""
 154                     if is_nullable:
 155                         ret_conv = (ret_conv[0], ret_conv[1] + "if (" + arr_name + " != NULL) {\n")
 156                         ret_conv = (ret_conv[0], ret_conv[1] + "\t" + ty_info.rust_obj + " " + arr_name + "_var = *" + arr_name + "_var_ptr;\n")
 157                         indent = "\t"
 158                     ret_conv = (ret_conv[0], ret_conv[1] + indent + arr_name + "_arr = " + self.consts.create_native_arr_call(arr_name + "_var." + arr_len, ty_info) + ";\n")
 159                     get_ptr_call = self.consts.get_native_arr_ptr_call(ty_info)
 160                     if get_ptr_call is not None:
 161                         ret_conv = (ret_conv[0], ret_conv[1] + indent + subty.c_ty + " *" + arr_name + "_arr_ptr = " + get_ptr_call[0] + arr_name + "_arr" + get_ptr_call[1] + ";\n")
 162                     ret_conv = (ret_conv[0], ret_conv[1] + indent + "for (size_t " + idxc + " = 0; " + idxc + " < " + arr_name + "_var." + arr_len + "; " + idxc + "++) {\n")
 163                     ret_conv = (ret_conv[0], ret_conv[1] + indent + "\t" + subty.ret_conv[0].replace("\n", "\n\t" + indent))
 164                     ret_conv = (ret_conv[0], ret_conv[1] + indent + arr_name + "_var." + ty_info.arr_access + "[" + idxc + "]" + subty.ret_conv[1].replace("\n", "\n\t" + indent) + "\n")
 165                     if get_ptr_call is not None:
 166                         ret_conv = (ret_conv[0], ret_conv[1] + indent + "\t" + arr_name + "_arr_ptr[" + idxc + "] = " + subty.ret_conv_name + ";\n" + indent + "}\n")
 167                     else:
 168                         ret_conv = (ret_conv[0], ret_conv[1] + indent + "\t" + self.consts.get_native_arr_entry_call(ty_info, arr_name + "_arr", idxc, subty.ret_conv_name) + ";\n" + indent + "}\n")
 169                     cleanup = self.consts.release_native_arr_ptr_call(ty_info, arr_name + "_arr", arr_name + "_arr_ptr")
 170                     if cleanup is not None:
 171                         ret_conv = (ret_conv[0], ret_conv[1] + indent + cleanup + ";")
 172                     if not holds_ref and not is_nullable:
 173                         # XXX: The commented if's are a bit smarter freeing, but we need to be a nudge smarter still
 174                         # Note that we don't drop the full vec here - we're passing ownership to java (or have cloned) or free'd by now!
 175                         ret_conv = (ret_conv[0], ret_conv[1] + "\n" + indent + "FREE(" + arr_name + "_var." + ty_info.arr_access + ");")
 176                         #if subty.rust_obj is not None and subty.rust_obj in self.opaque_structs:
 177                         #    ret_conv = (ret_conv[0], ret_conv[1] + "\nFREE(" + arr_name + "_var." + ty_info.arr_access + ");")
 178                         #else:
 179                         #    ret_conv = (ret_conv[0], ret_conv[1] + "\n" + ty_info.rust_obj.replace("LDK", "") + "_free(" + arr_name + "_var);")
 180                     if is_nullable:
 181                         ret_conv = (ret_conv[0], ret_conv[1] + "\n}")
 182
 183                 to_hu_conv = None
 184                 to_hu_conv_name = None
 185                 if subty.to_hu_conv is not None:
 186                     to_hu_conv = self.consts.var_decl_statement(ty_info.java_hu_ty, conv_name + "_arr", self.consts.constr_hu_array(ty_info, arr_name + ".length"))
 187                     to_hu_conv += ";\n" + self.consts.for_n_in_range(idxc, "0", arr_name + ".length") + "\n"
 188                     to_hu_conv += "\t" + self.consts.var_decl_statement(subty.java_ty, conv_name, arr_name + "[" + idxc + "]") + ";\n"
 189                     to_hu_conv += "\t" + subty.to_hu_conv.replace("\n", "\n\t") + "\n"
 190                     to_hu_conv += "\t" + conv_name + "_arr[" + idxc + "] = " + subty.to_hu_conv_name + ";\n}"
 191                     to_hu_conv_name = conv_name + "_arr"
 192                 from_hu_conv = None
 193                 if subty.from_hu_conv is not None:
 194                     hu_conv_b = ""
 195                     if subty.from_hu_conv[1] != "":
 196                         iterator = self.consts.for_n_in_arr(conv_name, arr_name, subty)
 197                         hu_conv_b = iterator[0] + subty.from_hu_conv[1] + ";" + iterator[1]
 198                     from_hu_conv = (self.consts.map_hu_array_elems(arr_name, conv_name, ty_info, subty), hu_conv_b)
 199
 200                 return ConvInfo(ty_info = ty_info, arg_name = ty_info.var_name,
 201                     arg_conv = arg_conv, arg_conv_name = arg_conv_name, arg_conv_cleanup = arg_conv_cleanup,
 202                     ret_conv = ret_conv, ret_conv_name = arr_name + "_arr", to_hu_conv = to_hu_conv, to_hu_conv_name = to_hu_conv_name, from_hu_conv = from_hu_conv)
 203         elif ty_info.java_ty == "String":
 204             assert not is_nullable
 205             if not is_free:
 206                 arg_conv = "LDKStr " + ty_info.var_name + "_conv = " + self.consts.str_ref_to_c_call(ty_info.var_name) + ";"
 207                 arg_conv_name = ty_info.var_name + "_conv"
 208             else:
 209                 arg_conv = "LDKStr dummy = { .chars = NULL, .len = 0, .chars_is_owned = false };"
 210                 arg_conv_name = "dummy"
 211             if ty_info.arr_access is None:
 212                 return ConvInfo(ty_info = ty_info, arg_name = ty_info.var_name,
 213                     arg_conv = arg_conv, arg_conv_name = arg_conv_name, arg_conv_cleanup = None,
 214                     ret_conv = ("const char* " + ty_info.var_name + "_str = ",
 215                         ";\njstring " + ty_info.var_name + "_conv = " + self.consts.str_ref_to_native_call(ty_info.var_name + "_str", "strlen(" + ty_info.var_name + "_str)") + ";"),
 216                     ret_conv_name = ty_info.var_name + "_conv",
 217                     to_hu_conv = None, to_hu_conv_name = None, from_hu_conv = None)
 218             else:
 219                 free_str = ""
 220                 if not holds_ref:
 221                     free_str = "\nStr_free(" + ty_info.var_name + "_str);"
 222                 return ConvInfo(ty_info = ty_info, arg_name = ty_info.var_name,
 223                     arg_conv = arg_conv, arg_conv_name = arg_conv_name, arg_conv_cleanup = None,
 224                     ret_conv = ("LDKStr " + ty_info.var_name + "_str = ",
 225                         ";\njstring " + ty_info.var_name + "_conv = " + self.consts.str_ref_to_native_call(ty_info.var_name + "_str." + ty_info.arr_access, ty_info.var_name + "_str." + ty_info.arr_len) + ";" + free_str),
 226                     ret_conv_name = ty_info.var_name + "_conv", to_hu_conv = None, to_hu_conv_name = None, from_hu_conv = None)
 227         elif ty_info.var_name == "" and not print_void:
 228             # We don't have a parameter name, and want one, just call it arg
 229             if not ty_info.is_native_primitive:
 230                 assert(not is_free or ty_info.rust_obj not in self.opaque_structs)
 231                 return ConvInfo(ty_info = ty_info, arg_name = ty_info.var_name,
 232                     arg_conv = ty_info.rust_obj + " arg_conv = *(" + ty_info.rust_obj + "*)arg;\nFREE((void*)arg);",
 233                     arg_conv_name = "arg_conv", arg_conv_cleanup = None,
 234                     ret_conv = None, ret_conv_name = None, to_hu_conv = "TODO 7", to_hu_conv_name = None, from_hu_conv = None)
 235             else:
 236                 assert(not is_free)
 237                 return ConvInfo(ty_info = ty_info, arg_name = ty_info.var_name,
 238                     arg_conv = None, arg_conv_name = "arg", arg_conv_cleanup = None,
 239                     ret_conv = None, ret_conv_name = None, to_hu_conv = "TODO 8", to_hu_conv_name = None, from_hu_conv = None)
 240         elif ty_info.is_native_primitive:
 241             assert not is_nullable
 242             return ConvInfo(ty_info = ty_info, arg_name = ty_info.var_name,
 243                 arg_conv = None, arg_conv_name = ty_info.var_name, arg_conv_cleanup = None,
 244                 ret_conv = None, ret_conv_name = None, to_hu_conv = None, to_hu_conv_name = None, from_hu_conv = None)
 245         else:
 246             if ty_info.var_name == "":
 247                 ty_info.var_name = "ret"
 248
 249             if ty_info.rust_obj in self.opaque_structs:
 250                 from_hu_conv = (ty_info.var_name + " == null ? 0 : " + self.consts.get_ptr(ty_info.var_name) + " & ~1", self.consts.add_ref("this", ty_info.var_name))
 251                 opaque_arg_conv = ty_info.rust_obj + " " + ty_info.var_name + "_conv;\n"
 252                 opaque_arg_conv = opaque_arg_conv + ty_info.var_name + "_conv.inner = (void*)(" + ty_info.var_name + " & (~1));\n"
 253                 if ty_info.is_ptr and holds_ref:
 254                     opaque_arg_conv += ty_info.var_name + "_conv.is_owned = false;\n"
 255                 else:
 256                     opaque_arg_conv += ty_info.var_name + "_conv.is_owned = (" + ty_info.var_name + " & 1) || (" + ty_info.var_name + " == 0);\n"
 257                 opaque_arg_conv += "CHECK_INNER_FIELD_ACCESS_OR_NULL(" + ty_info.var_name + "_conv);"
 258                 if not is_free and (not ty_info.is_ptr or not holds_ref or ty_info.requires_clone == True) and ty_info.requires_clone != False:
 259                     if (ty_info.rust_obj.replace("LDK", "") + "_clone") in self.clone_fns:
 260                         # TODO: This is a bit too naive, even with the checks above, we really need to know if rust wants a ref or not, not just if its pass as a ptr.
 261                         # arg_conv is used when converting a function argument from java normally (with holds_ref set),
 262                         # and when converting a java value being returned from a trait method (with holds_ref unset).
 263                         # In the second case, we need to clone before returning to C (as once we return the GC can free the object),
 264                         # whereas in the first we prefer to clone in C to avoid additional Java code as much as possible.
 265                         if holds_ref:
 266                             opaque_arg_conv = opaque_arg_conv + "\n" + ty_info.var_name + "_conv = " + ty_info.rust_obj.replace("LDK", "") + "_clone(&" + ty_info.var_name + "_conv);"
 267                             from_hu_conv = (from_hu_conv[0], "")
 268                         else:
 269                             from_hu_conv = (ty_info.var_name + " == null ? 0 : " + ty_info.var_name + ".clone_ptr()", "")
 270                     elif ty_info.passed_as_ptr:
 271                         opaque_arg_conv = opaque_arg_conv + "\n// Warning: we need a move here but no clone is available for " + ty_info.rust_obj
 272                         # TODO: Once we support features cloning (which just isn't in C yet), we can make this a compile error instead!
 273                         from_hu_conv = (from_hu_conv[0], from_hu_conv[1] + ";\n" +
 274                             "// Due to rust's strict-ownership memory model, in some cases we need to \"move\"\n" +
 275                             "// an object to pass exclusive ownership to the function being called.\n" +
 276                             "// In most cases, we avoid this being visible in GC'd languages by cloning the object\n" +
 277                             "// at the FFI layer, creating a new object which Rust can claim ownership of\n" +
 278                             "// However, in some cases (eg here), there is no way to clone an object, and thus\n" +
 279                             "// we actually have to pass full ownership to Rust.\n" +
 280                             "// Thus, after this call, " + ty_info.var_name + " is reset to null and is now a dummy object.\n" + self.consts.set_null_skip_free(ty_info.var_name))
 281
 282                 opaque_ret_conv_suf = ";\n"
 283                 opaque_ret_conv_suf += "uint64_t " + ty_info.var_name + "_ref = 0;\n"
 284                 indent = ""
 285                 if is_nullable:
 286                     opaque_ret_conv_suf += "if ((uint64_t)" + ty_info.var_name + "_var.inner > 4096) {\n"
 287                     indent = "\t"
 288                 if not holds_ref and ty_info.is_ptr and (ty_info.rust_obj.replace("LDK", "") + "_clone") in self.clone_fns: # is_ptr, not holds_ref implies passing a pointed-to value to java, which needs copied
 289                     opaque_ret_conv_suf += indent + ty_info.var_name + "_var = " + ty_info.rust_obj.replace("LDK", "") + "_clone(" + ty_info.var_name + ");\n"
 290                 elif not holds_ref and ty_info.is_ptr:
 291                     opaque_ret_conv_suf += indent + "// Warning: we may need a move here but no clone is available for " + ty_info.rust_obj + "\n"
 292
 293                 opaque_ret_conv_suf += indent + "CHECK((((uint64_t)" + ty_info.var_name + "_var.inner) & 1) == 0); // We rely on a free low bit, malloc guarantees this.\n"
 294                 opaque_ret_conv_suf += indent + "CHECK((((uint64_t)&" + ty_info.var_name + "_var) & 1) == 0); // We rely on a free low bit, pointer alignment guarantees this.\n"
 295                 opaque_ret_conv_suf += "CHECK_INNER_FIELD_ACCESS_OR_NULL(" + ty_info.var_name + "_var);\n"
 296                 if holds_ref:
 297                     opaque_ret_conv_suf += indent + ty_info.var_name + "_ref = (uint64_t)" + ty_info.var_name + "_var.inner & ~1;"
 298                 else:
 299                     opaque_ret_conv_suf += indent + ty_info.var_name + "_ref = (uint64_t)" + ty_info.var_name + "_var.inner;\n"
 300                     opaque_ret_conv_suf += indent + "if (" + ty_info.var_name + "_var.is_owned) {\n"
 301                     opaque_ret_conv_suf += indent + "\t" + ty_info.var_name + "_ref |= 1;\n"
 302                     opaque_ret_conv_suf += indent + "}"
 303                 if is_nullable:
 304                     opaque_ret_conv_suf += "\n}"
 305
 306                 to_hu_conv_sfx = ""
 307                 if not ty_info.is_ptr or holds_ref:
 308                     to_hu_conv_sfx = "\n" + self.consts.add_ref(ty_info.var_name + "_hu_conv", "this") + ";"
 309                 if ty_info.is_ptr:
 310                     return ConvInfo(ty_info = ty_info, arg_name = ty_info.var_name,
 311                         arg_conv = opaque_arg_conv, arg_conv_name = "&" + ty_info.var_name + "_conv", arg_conv_cleanup = None,
 312                         ret_conv = (ty_info.rust_obj + " " + ty_info.var_name + "_var = *", opaque_ret_conv_suf),
 313                         ret_conv_name = ty_info.var_name + "_ref",
 314                         to_hu_conv = self.consts.to_hu_conv_templates['ptr'].replace('{human_type}', ty_info.java_hu_ty).replace('{var_name}', ty_info.var_name) + to_hu_conv_sfx,
 315                         to_hu_conv_name = ty_info.var_name + "_hu_conv",
 316                         from_hu_conv = from_hu_conv)
 317                 else:
 318                     return ConvInfo(ty_info = ty_info, arg_name = ty_info.var_name,
 319                         arg_conv = opaque_arg_conv, arg_conv_name = ty_info.var_name + "_conv", arg_conv_cleanup = None,
 320                         ret_conv = (ty_info.rust_obj + " " + ty_info.var_name + "_var = ", opaque_ret_conv_suf),
 321                         ret_conv_name = ty_info.var_name + "_ref",
 322                         to_hu_conv = self.consts.to_hu_conv_templates['default'].replace('{human_type}', ty_info.java_hu_ty).replace('{var_name}', ty_info.var_name) + to_hu_conv_sfx,
 323                         to_hu_conv_name = ty_info.var_name + "_hu_conv",
 324                         from_hu_conv = from_hu_conv)
 325
 326             assert not is_nullable
 327             if not ty_info.is_ptr:
 328                 if ty_info.rust_obj in self.unitary_enums:
 329                     (ret_pfx, ret_sfx) = self.consts.c_unitary_enum_to_native_call(ty_info)
 330                     (arg_pfx, arg_sfx) = self.consts.native_unitary_enum_to_c_call(ty_info)
 331                     return ConvInfo(ty_info = ty_info, arg_name = ty_info.var_name,
 332                         arg_conv = ty_info.rust_obj + " " + ty_info.var_name + "_conv = " + arg_pfx + ty_info.var_name + arg_sfx + ";",
 333                         arg_conv_name = ty_info.var_name + "_conv",
 334                         arg_conv_cleanup = None,
 335                         ret_conv = (ty_info.c_ty + " " + ty_info.var_name + "_conv = " + ret_pfx, ret_sfx + ";"),
 336                         ret_conv_name = ty_info.var_name + "_conv", to_hu_conv = None, to_hu_conv_name = None, from_hu_conv = None)
 337                 base_conv = "void* " + ty_info.var_name + "_ptr = (void*)(((uint64_t)" + ty_info.var_name + ") & ~1);\n"
 338                 base_conv += "CHECK_ACCESS(" + ty_info.var_name + "_ptr);\n"
 339                 base_conv += ty_info.rust_obj + " " + ty_info.var_name + "_conv = *(" + ty_info.rust_obj + "*)(" + ty_info.var_name + "_ptr);"
 340                 from_hu_conv = None
 341                 if ty_info.rust_obj in self.trait_structs:
 342                     ret_conv = (ty_info.rust_obj + "* " + ty_info.var_name + "_ret = MALLOC(sizeof(" + ty_info.rust_obj + "), \"" + ty_info.rust_obj + "\");\n*" + ty_info.var_name + "_ret = ", ";")
 343                     if holds_ref:
 344                         if (ty_info.rust_obj.replace("LDK", "") + "_clone") in self.clone_fns:
 345                             ret_conv = (ret_conv[0] + ty_info.rust_obj.replace("LDK", "") + "_clone(&", ");")
 346                         else:
 347                             ret_conv = (ret_conv[0], ";\n// Warning: We likely need to clone here, but no clone is available, so we just do it for Java instances")
 348                             ret_conv = (ret_conv[0], ret_conv[1] + "" + self.consts.trait_struct_inc_refcnt(ty_info).replace(ty_info.var_name + "_conv", "(*" + ty_info.var_name + "_ret)"))
 349                     if not is_free:
 350                         needs_full_clone = not is_free and (not ty_info.is_ptr and not holds_ref or ty_info.requires_clone == True) and ty_info.requires_clone != False
 351                         if needs_full_clone and (ty_info.rust_obj.replace("LDK", "") + "_clone") in self.clone_fns:
 352                             # arg_conv is used when converting a function argument from java normally (with holds_ref set),
 353                             # and when converting a java value being returned from a trait method (with holds_ref unset).
 354                             # In the second case, we need to clone before returning to C (as once we return the GC can free the object),
 355                             # whereas in the first we prefer to clone in C to avoid additional Java code as much as possible.
 356                             if holds_ref:
 357                                 base_conv += "\n" + ty_info.var_name + "_conv = " + ty_info.rust_obj.replace("LDK", "") + "_clone(&" + ty_info.var_name + "_conv);"
 358                             else:
 359                                 from_hu_conv = (ty_info.var_name + " == null ? 0 : " + ty_info.var_name + ".clone_ptr()", "")
 360                                 base_conv += "\n" + "FREE((void*)" + ty_info.var_name + ");"
 361                         else:
 362                             base_conv = base_conv + self.consts.trait_struct_inc_refcnt(ty_info)
 363                             if needs_full_clone:
 364                                 base_conv = base_conv + "// Warning: we may need a move here but no clone is available for " + ty_info.rust_obj + "\n"
 365                     else:
 366                         base_conv = base_conv + "\n" + "FREE((void*)" + ty_info.var_name + ");"
 367                     if from_hu_conv is None:
 368                         from_hu_conv = (ty_info.var_name + " == null ? 0 : " + self.consts.get_ptr(ty_info.var_name), "")
 369                     from_hu_conv = (from_hu_conv[0], self.consts.add_ref("this", ty_info.var_name))
 370                     return ConvInfo(ty_info = ty_info, arg_name = ty_info.var_name,
 371                         arg_conv = base_conv, arg_conv_name = ty_info.var_name + "_conv", arg_conv_cleanup = None,
 372                         ret_conv = ret_conv, ret_conv_name = "(uint64_t)" + ty_info.var_name + "_ret",
 373                         to_hu_conv = self.consts.var_decl_statement(ty_info.java_hu_ty, "ret_hu_conv", "new " + ty_info.java_hu_ty + "(null, " + ty_info.var_name + ")") + ";\n" + self.consts.add_ref("ret_hu_conv", "this") + ";",
 374                         to_hu_conv_name = "ret_hu_conv", from_hu_conv = from_hu_conv)
 375                 needs_full_clone = not is_free and (not ty_info.is_ptr or ty_info.requires_clone == True) and ty_info.requires_clone != False
 376                 if needs_full_clone:
 377                     if "res" in ty_info.var_name: # XXX: This is a stupid hack
 378                         needs_full_clone = False
 379                     if needs_full_clone and (ty_info.rust_obj.replace("LDK", "") + "_clone") in self.clone_fns:
 380                         # arg_conv is used when converting a function argument from java normally (with holds_ref set),
 381                         # and when converting a java value being returned from a trait method (with holds_ref unset).
 382                         # In the second case, we need to clone before returning to C (as once we return the GC can free the object),
 383                         # whereas in the first we prefer to clone in C to avoid additional Java code as much as possible.
 384                         if holds_ref:
 385                             base_conv += "\n" + ty_info.var_name + "_conv = " + ty_info.rust_obj.replace("LDK", "") + "_clone((" + ty_info.rust_obj + "*)(((uint64_t)" + ty_info.var_name + ") & ~1));"
 386                         else:
 387                             from_hu_conv = (ty_info.var_name + " == null ? 0 : " + ty_info.var_name + ".clone_ptr()", "")
 388                             base_conv += "\n" + "FREE((void*)" + ty_info.var_name + ");"
 389                     elif needs_full_clone:
 390                         base_conv = base_conv + "\n// Warning: we may need a move here but no clone is available for " + ty_info.rust_obj
 391                 if not needs_full_clone and ty_info.rust_obj != "LDKu8slice" and (not holds_ref or is_free):
 392                     # Don't bother free'ing slices passed in - Rust doesn't auto-free the
 393                     # underlying unlike Vecs, and it gives Java more freedom.
 394                     base_conv = base_conv + "\nFREE((void*)" + ty_info.var_name + ");"
 395                 if ty_info.rust_obj in self.complex_enums:
 396                     to_hu_conv_sfx = ""
 397                     if needs_full_clone and (ty_info.rust_obj.replace("LDK", "") + "_clone") not in self.clone_fns:
 398                         # We really need a full clone here, but for now we just implement
 399                         # a manual clone explicitly for Option<Trait>s
 400                         if ty_info.contains_trait:
 401                             assert ty_info.rust_obj.startswith("LDKCOption") # We don't support contained traits for anything else yet
 402                             optional_ty = ty_info.rust_obj[11:-1]
 403                             assert "LDK" + optional_ty in self.trait_structs # We don't support contained traits for anything else yet
 404                             to_hu_conv_sfx = self.consts.add_ref("this", ty_info.var_name)
 405                             base_conv += "\nif (" + ty_info.var_name + "_conv.tag == " + ty_info.rust_obj + "_Some) {"
 406                             base_conv += "\n\t// Manually implement clone for Java trait instances"
 407                             optional_ty_info = self.java_c_types("LDK" + optional_ty + " " + ty_info.var_name, None)
 408                             base_conv += self.consts.trait_struct_inc_refcnt(optional_ty_info).\
 409                                 replace("\n", "\n\t").replace(ty_info.var_name + "_conv", ty_info.var_name + "_conv.some")
 410                             base_conv += "\n}"
 411                     ret_conv = ("uint64_t " + ty_info.var_name + "_ref = ((uint64_t)&", ") | 1;")
 412                     if not holds_ref:
 413                         ret_conv = (ty_info.rust_obj + " *" + ty_info.var_name + "_copy = MALLOC(sizeof(" + ty_info.rust_obj + "), \"" + ty_info.rust_obj + "\");\n", "")
 414                         ret_conv = (ret_conv[0] + "*" + ty_info.var_name + "_copy = ", "")
 415                         ret_conv = (ret_conv[0], ";\nuint64_t " + ty_info.var_name + "_ref = (uint64_t)" + ty_info.var_name + "_copy;")
 416                     if from_hu_conv is None:
 417                         from_hu_conv = (self.consts.get_ptr(ty_info.var_name), "")
 418                     from_hu_conv = (from_hu_conv[0], to_hu_conv_sfx)
 419                     return ConvInfo(ty_info = ty_info, arg_name = ty_info.var_name,
 420                         arg_conv = base_conv, arg_conv_name = ty_info.var_name + "_conv", arg_conv_cleanup = None,
 421                         ret_conv = ret_conv, ret_conv_name = ty_info.var_name + "_ref",
 422                         to_hu_conv = self.consts.var_decl_statement(ty_info.java_hu_ty, ty_info.var_name + "_hu_conv", ty_info.java_hu_ty + ".constr_from_ptr(" + ty_info.var_name + ")") + ";\n" + self.consts.add_ref(ty_info.var_name + "_hu_conv", "this") + ";",
 423                         to_hu_conv_name = ty_info.var_name + "_hu_conv", from_hu_conv = from_hu_conv)
 424                 if ty_info.rust_obj in self.result_types:
 425                     if holds_ref:
 426                         # If we're trying to return a ref, we have to clone.
 427                         # We just blindly assume its implemented and let the compiler fail if its not.
 428                         ret_conv = (ty_info.rust_obj + "* " + ty_info.var_name + "_conv = MALLOC(sizeof(" + ty_info.rust_obj + "), \"" + ty_info.rust_obj + "\");\n*" + ty_info.var_name + "_conv = ", ";")
 429                         ret_conv = (ret_conv[0], ret_conv[1] + "\n*" + ty_info.var_name + "_conv = " + ty_info.rust_obj.replace("LDK", "") + "_clone(" + ty_info.var_name + "_conv);")
 430                     else:
 431                         ret_conv = (ty_info.rust_obj + "* " + ty_info.var_name + "_conv = MALLOC(sizeof(" + ty_info.rust_obj + "), \"" + ty_info.rust_obj + "\");\n*" + ty_info.var_name + "_conv = ", ";")
 432                     if from_hu_conv is None:
 433                         from_hu_conv = (ty_info.var_name + " != null ? " + self.consts.get_ptr(ty_info.var_name) + " : 0", "")
 434                     return ConvInfo(ty_info = ty_info, arg_name = ty_info.var_name,
 435                         arg_conv = base_conv, arg_conv_name = ty_info.var_name + "_conv", arg_conv_cleanup = None,
 436                         ret_conv = ret_conv, ret_conv_name = "(uint64_t)" + ty_info.var_name + "_conv",
 437                         to_hu_conv = self.consts.var_decl_statement(ty_info.java_hu_ty, ty_info.var_name + "_hu_conv", ty_info.java_hu_ty + ".constr_from_ptr(" + ty_info.var_name + ")") + ";",
 438                         to_hu_conv_name = ty_info.var_name + "_hu_conv", from_hu_conv = from_hu_conv)
 439                 if ty_info.rust_obj in self.tuple_types:
 440                     ret_conv_name = "((uint64_t)" + ty_info.var_name + "_conv)"
 441                     if holds_ref:
 442                         # If we're trying to return a ref, we have to clone.
 443                         if (ty_info.rust_obj.replace("LDK", "") + "_clone") not in self.clone_fns:
 444                             ret_conv = (ty_info.rust_obj + "* " + ty_info.var_name + "_conv = &", "")
 445                             ret_conv = (ret_conv[0], ";\n// Warning: we really need to clone here, but no clone is available for " + ty_info.rust_obj)
 446                             ret_conv_name += " | 1"
 447                         else:
 448                             ret_conv = (ty_info.rust_obj + "* " + ty_info.var_name + "_conv = MALLOC(sizeof(" + ty_info.rust_obj + "), \"" + ty_info.rust_obj + "\");\n*" + ty_info.var_name + "_conv = ", ";")
 449                             ret_conv = (ret_conv[0], ret_conv[1] + "\n*" + ty_info.var_name + "_conv = " + ty_info.rust_obj.replace("LDK", "") + "_clone(" + ty_info.var_name + "_conv);")
 450                     else:
 451                         ret_conv = (ty_info.rust_obj + "* " + ty_info.var_name + "_conv = MALLOC(sizeof(" + ty_info.rust_obj + "), \"" + ty_info.rust_obj + "\");\n*" + ty_info.var_name + "_conv = ", ";")
 452                     if not ty_info.is_ptr or holds_ref:
 453                         to_hu_conv_sfx = "\n" + self.consts.add_ref(ty_info.var_name + "_hu_conv", "this") + ";"
 454                     else:
 455                         to_hu_conv_sfx = ""
 456                     if from_hu_conv is None:
 457                         from_hu_conv = (ty_info.var_name + " != null ? " + self.consts.get_ptr(ty_info.var_name) + " : 0", "")
 458                     return ConvInfo(ty_info = ty_info, arg_name = ty_info.var_name,
 459                         arg_conv = base_conv, arg_conv_name = ty_info.var_name + "_conv", arg_conv_cleanup = None,
 460                         ret_conv = ret_conv, ret_conv_name = ret_conv_name,
 461                         to_hu_conv = self.consts.var_decl_statement(ty_info.java_hu_ty, ty_info.var_name + "_hu_conv", "new " + ty_info.java_hu_ty + "(null, " + ty_info.var_name + ")") + ";" + to_hu_conv_sfx,
 462                         to_hu_conv_name = ty_info.var_name + "_hu_conv", from_hu_conv = from_hu_conv)
 463
 464                 # The manually-defined types - TxOut and u5
 465                 if ty_info.rust_obj == "LDKu5":
 466                     assert from_hu_conv is None
 467                     return ConvInfo(ty_info = ty_info, arg_name = ty_info.var_name,
 468                         arg_conv = "", arg_conv_name = "(LDKu5){ ._0 = " + ty_info.var_name + " }", arg_conv_cleanup = None,
 469                         ret_conv = ("uint8_t " + ty_info.var_name + "_val = ", "._0;"), ret_conv_name = ty_info.var_name + "_val",
 470                         to_hu_conv = self.consts.var_decl_statement(ty_info.java_hu_ty, ty_info.var_name + "_conv", "new " + ty_info.java_hu_ty + "(" + ty_info.var_name + ")") + ";",
 471                         to_hu_conv_name = ty_info.var_name + "_conv", from_hu_conv = (ty_info.var_name + ".getVal()", ""))
 472
 473                 assert ty_info.rust_obj == "LDKTxOut"
 474                 if not ty_info.is_ptr and not holds_ref:
 475                     ret_conv = ("LDKTxOut* " + ty_info.var_name + "_ref = MALLOC(sizeof(LDKTxOut), \"LDKTxOut\");\n*" + ty_info.var_name + "_ref = ", ";")
 476                 else:
 477                     ret_conv = ("uint64_t " + ty_info.var_name + "_ref = ((uint64_t)&", ") | 1;")
 478                 return ConvInfo(ty_info = ty_info, arg_name = ty_info.var_name,
 479                     arg_conv = base_conv, arg_conv_name = ty_info.var_name + "_conv", arg_conv_cleanup = None,
 480                     ret_conv = ret_conv, ret_conv_name = "(uint64_t)" + ty_info.var_name + "_ref",
 481                     to_hu_conv = self.consts.var_decl_statement(ty_info.java_hu_ty, ty_info.var_name + "_conv", "new " +ty_info.java_hu_ty + "(null, " + ty_info.var_name + ")") + ";",
 482                     to_hu_conv_name = ty_info.var_name + "_conv", from_hu_conv = (self.consts.get_ptr(ty_info.var_name), ""))
 483             elif ty_info.is_ptr:
 484                 assert(not is_free)
 485                 if ty_info.rust_obj in self.complex_enums:
 486                     ret_conv = ("uint64_t ret_" + ty_info.var_name + " = (uint64_t)", " | 1; // Warning: We should clone here!")
 487                     from_hu_sfx = self.consts.add_ref("this", ty_info.var_name)
 488                     if ty_info.rust_obj.replace("LDK", "") + "_clone" in self.clone_fns:
 489                         ret_conv_pfx = ty_info.rust_obj + " *ret_" + ty_info.var_name + " = MALLOC(sizeof(" + ty_info.rust_obj + "), \"" + ty_info.rust_obj + " ret conversion\");\n"
 490                         ret_conv_pfx += "*ret_" + ty_info.var_name + " = " + ty_info.rust_obj.replace("LDK", "") + "_clone("
 491                         ret_conv = (ret_conv_pfx, ");")
 492                         from_hu_sfx = ""
 493                     return ConvInfo(ty_info = ty_info, arg_name = ty_info.var_name,
 494                         arg_conv = ty_info.rust_obj + "* " + ty_info.var_name + "_conv = (" + ty_info.rust_obj + "*)" + ty_info.var_name + ";",
 495                         arg_conv_name = ty_info.var_name + "_conv", arg_conv_cleanup = None,
 496                         ret_conv = ret_conv, ret_conv_name = "(uint64_t)ret_" + ty_info.var_name,
 497                         to_hu_conv = self.consts.var_decl_statement(ty_info.java_hu_ty, ty_info.var_name + "_hu_conv", ty_info.java_hu_ty + ".constr_from_ptr(" + ty_info.var_name + ")") + ";",
 498                         to_hu_conv_name = ty_info.var_name + "_hu_conv",
 499                         from_hu_conv = (ty_info.var_name + " == null ? 0 : " + self.consts.get_ptr(ty_info.var_name) + " & ~1", from_hu_sfx))
 500                 elif ty_info.rust_obj in self.trait_structs:
 501                     if ty_info.nonnull_ptr:
 502                         arg_conv = "void* " + ty_info.var_name + "_ptr = (void*)(((uint64_t)" + ty_info.var_name + ") & ~1);\n"
 503                         arg_conv += "if (!(" + ty_info.var_name + " & 1)) { CHECK_ACCESS(" + ty_info.var_name + "_ptr); }\n"
 504                         arg_conv += ty_info.rust_obj + "* " + ty_info.var_name + "_conv = (" + ty_info.rust_obj + "*)" + ty_info.var_name + "_ptr;"
 505                         arg_conv_name = ty_info.var_name + "_conv"
 506                     else:
 507                         # We map Option<Trait> as *mut Trait, which we can differentiate from &Trait by the NONNULL_PTR annotation.
 508                         # We handle the Option<Trait> case here.
 509                         arg_conv = ty_info.rust_obj + " *" + ty_info.var_name + "_conv_ptr = NULL;\n"
 510                         arg_conv += "if (" + ty_info.var_name + " != 0) {\n"
 511                         arg_conv += "\t" + ty_info.rust_obj + " " + ty_info.var_name + "_conv;\n"
 512                         arg_conv += "void* " + ty_info.var_name + "_ptr = (void*)(((uint64_t)" + ty_info.var_name + ") & ~1);\n"
 513                         arg_conv += "CHECK_ACCESS(" + ty_info.var_name + "_ptr);\n"
 514                         arg_conv += "\t" + ty_info.var_name + "_conv = *(" + ty_info.rust_obj + "*)" + ty_info.var_name + "_ptr;"
 515                         arg_conv += self.consts.trait_struct_inc_refcnt(ty_info).replace("\n", "\n\t")
 516                         arg_conv += "\n\t" + ty_info.var_name + "_conv_ptr = MALLOC(sizeof(" + ty_info.rust_obj + "), \"" + ty_info.rust_obj + "\");\n"
 517                         arg_conv += "\t*" + ty_info.var_name + "_conv_ptr = " + ty_info.var_name + "_conv;\n"
 518                         arg_conv += "}"
 519                         arg_conv_name = ty_info.var_name + "_conv_ptr"
 520                     if ty_info.rust_obj.replace("LDK", "") + "_clone" in self.clone_fns:
 521                         return ConvInfo(ty_info = ty_info, arg_name = ty_info.var_name,
 522                             arg_conv = arg_conv, arg_conv_name = arg_conv_name, arg_conv_cleanup = None,
 523                             ret_conv = (ty_info.rust_obj + " *" + ty_info.var_name + "_clone = MALLOC(sizeof(" + ty_info.rust_obj + "), \"" + ty_info.rust_obj + "\");\n" +
 524                                 "*" + ty_info.var_name + "_clone = " + ty_info.rust_obj.replace("LDK", "") + "_clone(", ");"),
 525                             ret_conv_name = "(uint64_t)" + ty_info.var_name + "_clone",
 526                             to_hu_conv = self.consts.var_decl_statement(ty_info.java_hu_ty, "ret_hu_conv", "new " + ty_info.java_hu_ty + "(null, " + ty_info.var_name + ")") + ";\n" + self.consts.add_ref("ret_hu_conv", "this") + ";",
 527                             to_hu_conv_name = "ret_hu_conv",
 528                             from_hu_conv = (ty_info.var_name + " == null ? 0 : " + self.consts.get_ptr(ty_info.var_name), ""))
 529                     else:
 530                         return ConvInfo(ty_info = ty_info, arg_name = ty_info.var_name,
 531                             arg_conv = arg_conv, arg_conv_name = arg_conv_name, arg_conv_cleanup = None,
 532                             ret_conv = ("// WARNING: This object doesn't live past this scope, needs clone!\nuint64_t ret_" + ty_info.var_name + " = ((uint64_t)", ") | 1;"),
 533                             ret_conv_name = "ret_" + ty_info.var_name,
 534                             to_hu_conv = self.consts.var_decl_statement(ty_info.java_hu_ty, "ret_hu_conv", "new " + ty_info.java_hu_ty + "(null, " + ty_info.var_name + ")") + ";\n" + self.consts.add_ref("ret_hu_conv", "this") + ";",
 535                             to_hu_conv_name = "ret_hu_conv",
 536                             from_hu_conv = (ty_info.var_name + " == null ? 0 : " + self.consts.get_ptr(ty_info.var_name), self.consts.add_ref("this", ty_info.var_name)))
 537                 ret_conv = ("uint64_t ret_" + ty_info.var_name + " = (uint64_t)", ";")
 538                 if holds_ref:
 539                     ret_conv = (ret_conv[0], " | 1;")
 540                 return ConvInfo(ty_info = ty_info, arg_name = ty_info.var_name,
 541                     arg_conv = ty_info.rust_obj + "* " + ty_info.var_name + "_conv = (" + ty_info.rust_obj + "*)(" + ty_info.var_name + " & ~1);",
 542                     arg_conv_name = ty_info.var_name + "_conv", arg_conv_cleanup = None,
 543                     ret_conv = ret_conv, ret_conv_name = "ret_" + ty_info.var_name,
 544                     to_hu_conv = "TODO 3", to_hu_conv_name = None, from_hu_conv = None) # its a pointer, no conv needed
 545             assert False # We should have handled every case by now.