fix DOL loader

src/FunctionCompiler.cc

@@ -227,7 +227,7 @@ shared_ptr<const Menu> FunctionCodeIndex::patch_menu(uint32_t specific_version)
   auto suffix = string_printf("-%08" PRIX32, specific_version);
 
   shared_ptr<Menu> ret(new Menu(MenuID::PATCHES, u"Patches"));
-  ret->items.emplace_back(PatchesMenuItemID::GO_BACK, u"Go back", u"", 0);
+  ret->items.emplace_back(PatchesMenuItemID::GO_BACK, u"Go back", u"Return to the\nmain menu", 0);
   for (const auto& it : this->name_and_specific_version_to_patch_function) {
     const auto& fn = it.second;
     if (!fn->hide_from_patches_menu && ends_with(it.first, suffix)) {
@@ -259,7 +259,7 @@ DOLFileIndex::DOLFileIndex(const string& directory) {
 
   shared_ptr<Menu> menu(new Menu(MenuID::PROGRAMS, u"Programs"));
   this->menu = menu;
-  menu->items.emplace_back(ProgramsMenuItemID::GO_BACK, u"Go back", u"", 0);
+  menu->items.emplace_back(ProgramsMenuItemID::GO_BACK, u"Go back", u"Return to the\nmain menu", 0);
 
   uint32_t next_menu_item_id = 0;
   for (const auto& filename : list_directory(directory)) {

src/ReceiveCommands.cc

@@ -1733,6 +1733,13 @@ static void on_10(shared_ptr<ServerState> s, shared_ptr<Client> c,
           break;
 
         case MainMenuItemID::PROGRAMS:
+          if (!function_compiler_available()) {
+            throw runtime_error("function compiler not available");
+          }
+          if (c->flags & Client::Flag::NO_SEND_FUNCTION_CALL) {
+            throw runtime_error("client does not support send_function_call");
+          }
+          send_cache_patch_if_needed(s, c);
           send_menu(c, s->dol_file_index->menu);
           break;
 
@@ -2243,7 +2250,11 @@ static void send_dol_file_chunk(shared_ptr<ServerState> s, shared_ptr<Client> c,
   if (offset >= c->loading_dol_file->data.size()) {
     throw logic_error("DOL file offset beyond end of data");
   }
-  size_t bytes_to_send = min<size_t>(0x7800, c->loading_dol_file->data.size() - offset);
+  // Note: The protocol allows commands to be up to 0x7C00 bytes in size, but
+  // sending large B2 commands can cause the client to crash or softlock. To
+  // avoid this, we limit the payload to 4KB, which results in a B2 command
+  // 0x10D0 bytes in size.
+  size_t bytes_to_send = min<size_t>(0x1000, c->loading_dol_file->data.size() - offset);
   string data_to_send = c->loading_dol_file->data.substr(offset, bytes_to_send);
 
   auto fn = s->function_code_index->name_to_function.at("WriteMemory");
@@ -2252,8 +2263,7 @@ static void send_dol_file_chunk(shared_ptr<ServerState> s, shared_ptr<Client> c,
   send_function_call(c, fn, label_writes, data_to_send);
 
   size_t progress_percent = ((offset + bytes_to_send) * 100) / c->loading_dol_file->data.size();
-  string info = string_printf("Loading $C6%s$C7\n%zu%%%% complete",
-      c->loading_dol_file->name.c_str(), progress_percent);
+  string info = string_printf("%zu%%%%", progress_percent);
   send_ship_info(c, decode_sjis(info));
 }
 

system/ppc/ReadMemoryWord.s

@@ -8,6 +8,7 @@ reloc0:
   .offsetof start
 
 start:
+  mflr   r12
   bl     read
 address:
   .zero

system/ppc/RunDOL.s

@@ -8,7 +8,6 @@ reloc0:
   .offsetof start
 
 start:
-
 disable_interrupts:
   mfmsr   r3
   rlwinm  r3, r3, 0, 17, 15
@@ -21,7 +20,7 @@ get_current_addr:
   mflr    r31
   # TODO: It'd be nice to be able to use an expression for the immediate value
   # here - something like (dol_base_ptr - start), for example
-  subi    r31, r31, 0x38  # r31 = base of data to copy to low memory (start label)
+  subi    r31, r31, 0x10  # r31 = base of data to copy to low memory (start label)
 
   # If this code is not running from low memory (80001800-80003000), then copy
   # it there and branch to it
@@ -54,7 +53,7 @@ copy_code_to_low_memory__again:
 
 
 run_dol:
-  lwz     r30, [r31 + 0x38]  # r30 = DOL base ptr
+  lwz     r30, [r31 + 0x10]  # r30 = DOL base ptr
 
   # DOL files are very simple: they have up to 7 text sections, up to 11 data
   # sections, and a BSS section and an entrypoint. No imports or other fancy

system/ppc/WriteMemory.s

@@ -59,6 +59,7 @@ reloc0:
   .offsetof start
 
 start:
+  mflr    r12
   bl      get_block_ptr
   mr      r6, r3        # r6 = address of dest_addr label