[Emulator] Launch file based on signature instead of file extension

src/xenia/app/emulator_window.cc

@@ -1534,6 +1534,11 @@ void EmulatorWindow::DisplayHotKeysConfig() {
                                       msg);
 }
 
+std::string EmulatorWindow::CanonicalizeFileExtension(
+    const std::filesystem::path& path) {
+  return xe::utf8::lower_ascii(xe::path_to_utf8(path.extension()));
+}
+
 xe::X_STATUS EmulatorWindow::RunTitle(std::filesystem::path path_to_file) {
   bool titleExists = !std::filesystem::exists(path_to_file);
 
@@ -1564,6 +1569,20 @@ xe::X_STATUS EmulatorWindow::RunTitle(std::filesystem::path path_to_file) {
   // Prevent crashing the emulator by not loading a game if a game is already
   // loaded.
   auto abs_path = std::filesystem::absolute(path_to_file);
+
+  auto extension = CanonicalizeFileExtension(abs_path);
+
+  if (extension == ".7z" || extension == ".zip" || extension == ".rar" ||
+      extension == ".tar" || extension == ".gz") {
+    xe::ShowSimpleMessageBox(
+        xe::SimpleMessageBoxType::Error,
+        fmt::format(
+            "Unsupported format!\n"
+            "Xenia does not support running software in an archived format."));
+
+    return X_STATUS_UNSUCCESSFUL;
+  }
+
   auto result = emulator_->LaunchPath(abs_path);
 
   imgui_drawer_.get()->ClearDialogs();

src/xenia/app/emulator_window.h

@@ -228,6 +228,9 @@ class EmulatorWindow {
   bool IsUseNexusForGameBarEnabled();
   void DisplayHotKeysConfig();
 
+  static std::string CanonicalizeFileExtension(
+      const std::filesystem::path& path);
+
   void RunPreviouslyPlayedTitle();
   void FillRecentlyLaunchedTitlesMenu(xe::ui::MenuItem* recent_menu);
   void LoadRecentlyLaunchedTitles();

src/xenia/emulator.cc

@@ -15,6 +15,7 @@
 #include "config.h"
 #include "third_party/fmt/include/fmt/format.h"
 #include "third_party/tabulate/single_include/tabulate/tabulate.hpp"
+#include "third_party/zarchive/include/zarchive/zarchivecommon.h"
 #include "xenia/apu/audio_system.h"
 #include "xenia/base/assert.h"
 #include "xenia/base/byte_stream.h"
@@ -314,32 +315,35 @@ X_STATUS Emulator::TerminateTitle() {
   return X_STATUS_SUCCESS;
 }
 
-std::string Emulator::CanonicalizeFileExtension(
-    const std::filesystem::path& path) {
-  return xe::utf8::lower_ascii(xe::path_to_utf8(path.extension()));
-}
-
-const std::unique_ptr<vfs::Device> Emulator::CreateVfsDeviceBasedOnPath(
+const std::unique_ptr<vfs::Device> Emulator::CreateVfsDevice(
     const std::filesystem::path& path, const std::string_view mount_path) {
-  if (!path.has_extension()) {
-    return vfs::XContentContainerDevice::CreateContentDevice(mount_path, path);
+  // Must check if the type has changed e.g. XamSwapDisc
+  switch (GetFileSignature(path)) {
+    case FileSignatureType::XEX1:
+    case FileSignatureType::XEX2:
+    case FileSignatureType::ELF: {
+      auto parent_path = path.parent_path();
+      return std::make_unique<vfs::HostPathDevice>(
+          mount_path, parent_path, !cvars::allow_game_relative_writes);
+    } break;
+    case FileSignatureType::LIVE:
+    case FileSignatureType::CON:
+    case FileSignatureType::PIRS: {
+      return vfs::XContentContainerDevice::CreateContentDevice(mount_path,
+                                                               path);
+    } break;
+    case FileSignatureType::XISO: {
+      return std::make_unique<vfs::DiscImageDevice>(mount_path, path);
+    } break;
+    case FileSignatureType::ZAR: {
+      return std::make_unique<vfs::DiscZarchiveDevice>(mount_path, path);
+    } break;
+    case FileSignatureType::EXE:
+    case FileSignatureType::Unknown:
+    default:
+      return nullptr;
+      break;
   }
-  auto extension = CanonicalizeFileExtension(path);
-  if (extension == ".xex" || extension == ".elf" || extension == ".exe") {
-    auto parent_path = path.parent_path();
-    return std::make_unique<vfs::HostPathDevice>(
-        mount_path, parent_path, !cvars::allow_game_relative_writes);
-  } else if (extension == ".zar") {
-    return std::make_unique<vfs::DiscZarchiveDevice>(mount_path, path);
-  } else if (extension == ".7z" || extension == ".zip" || extension == ".rar" ||
-             extension == ".tar" || extension == ".gz") {
-    xe::ShowSimpleMessageBox(
-        xe::SimpleMessageBoxType::Error,
-        fmt::format(
-            "Unsupported format!\n"
-            "Xenia does not support running software in an archived format."));
-  }
-  return std::make_unique<vfs::DiscImageDevice>(mount_path, path);
 }
 
 uint64_t Emulator::GetPersistentEmulatorFlags() {
@@ -386,7 +390,7 @@ void Emulator::SetPersistentEmulatorFlags(uint64_t new_flags) {
 
 X_STATUS Emulator::MountPath(const std::filesystem::path& path,
                              const std::string_view mount_path) {
-  auto device = CreateVfsDeviceBasedOnPath(path, mount_path);
+  auto device = CreateVfsDevice(path, mount_path);
   if (!device || !device->Initialize()) {
     XELOGE(
         "Unable to mount the selected file, it is an unsupported format or "
@@ -410,30 +414,108 @@ X_STATUS Emulator::MountPath(const std::filesystem::path& path,
   return X_STATUS_SUCCESS;
 }
 
-X_STATUS Emulator::LaunchPath(const std::filesystem::path& path) {
-  // Launch based on file type.
-  // This is a silly guess based on file extension.
+Emulator::FileSignatureType Emulator::GetFileSignature(
+    const std::filesystem::path& path) {
+  FILE* file = xe::filesystem::OpenFile(path, "rb");
 
+  if (!file) {
+    return FileSignatureType::Unknown;
+  }
+
+  const uint64_t file_size = std::filesystem::file_size(path);
+  const uint64_t header_size = 4;
+
+  if (file_size < header_size) {
+    return FileSignatureType::Unknown;
+  }
+
+  char file_magic[header_size];
+  fread_s(file_magic, sizeof(file_magic), 1, header_size, file);
+
+  fourcc_t magic_value =
+      make_fourcc(file_magic[0], file_magic[1], file_magic[2], file_magic[3]);
+
+  fclose(file);
+
+  switch (magic_value) {
+    case xe::cpu::kXEX1Signature:
+      return FileSignatureType::XEX1;
+    case xe::cpu::kXEX2Signature:
+      return FileSignatureType::XEX2;
+    case xe::vfs::kCONSignature:
+      return FileSignatureType::CON;
+    case xe::vfs::kLIVESignature:
+      return FileSignatureType::LIVE;
+    case xe::vfs::kPIRSSignature:
+      return FileSignatureType::PIRS;
+    case xe::vfs::kXSFSignature:
+      return FileSignatureType::XISO;
+    case xe::cpu::kElfSignature:
+      return FileSignatureType::ELF;
+    default:
+      break;
+  }
+
+  magic_value = make_fourcc(file_magic[0], file_magic[1], 0, 0);
+
+  if (xe::kernel::kEXESignature == magic_value) {
+    return FileSignatureType::EXE;
+  }
+
+  file = xe::filesystem::OpenFile(path, "rb");
+  xe::filesystem::Seek(file, header_size, SEEK_END);
+  fread_s(file_magic, sizeof(file_magic), 1, header_size, file);
+  fclose(file);
+
+  magic_value =
+      make_fourcc(file_magic[0], file_magic[1], file_magic[2], file_magic[3]);
+
+  if (xe::vfs::kZarMagic == magic_value) {
+    return FileSignatureType::ZAR;
+  }
+
+  // Check if XISO
+  std::unique_ptr<vfs::Device> device =
+      std::make_unique<vfs::DiscImageDevice>("", path);
+
+  XELOGI("Checking for XISO");
+
+  if (device->Initialize()) {
+    return FileSignatureType::XISO;
+  }
+
+  return FileSignatureType::Unknown;
+}
+
+X_STATUS Emulator::LaunchPath(const std::filesystem::path& path) {
   X_STATUS mount_result = X_STATUS_SUCCESS;
 
-  if (!path.has_extension()) {
-    // Likely an STFS container.
-    mount_result = MountPath(path, "\\Device\\Cdrom0");
-    return mount_result ? mount_result : LaunchStfsContainer(path);
-  };
-  auto extension = xe::utf8::lower_ascii(xe::path_to_utf8(path.extension()));
-  if (extension == ".xex" || extension == ".elf" || extension == ".exe") {
-    // Treat as a naked xex file.
-    mount_result = MountPath(path, "\\Device\\Harddisk0\\Partition1");
-    return mount_result ? mount_result : LaunchXexFile(path);
-  } else if (extension == ".zar") {
-    // Assume a disc image.
-    mount_result = MountPath(path, "\\Device\\Cdrom0");
-    return mount_result ? mount_result : LaunchDiscArchive(path);
-  } else {
-    // Assume a disc image.
-    mount_result = MountPath(path, "\\Device\\Cdrom0");
-    return mount_result ? mount_result : LaunchDiscImage(path);
+  switch (GetFileSignature(path)) {
+    case FileSignatureType::XEX1:
+    case FileSignatureType::XEX2:
+    case FileSignatureType::ELF: {
+      mount_result = MountPath(path, "\\Device\\Harddisk0\\Partition1");
+      return mount_result ? mount_result : LaunchXexFile(path);
+    } break;
+    case FileSignatureType::LIVE:
+    case FileSignatureType::CON:
+    case FileSignatureType::PIRS: {
+      mount_result = MountPath(path, "\\Device\\Cdrom0");
+      return mount_result ? mount_result : LaunchStfsContainer(path);
+    } break;
+    case FileSignatureType::XISO: {
+      mount_result = MountPath(path, "\\Device\\Cdrom0");
+      return mount_result ? mount_result : LaunchDiscImage(path);
+    } break;
+    case FileSignatureType::ZAR: {
+      mount_result = MountPath(path, "\\Device\\Cdrom0");
+      return mount_result ? mount_result : LaunchDiscArchive(path);
+    } break;
+    case FileSignatureType::EXE:
+    case FileSignatureType::Unknown:
+    default:
+      return X_STATUS_NOT_SUPPORTED;
+      break;
   }
 }
 

src/xenia/emulator.h

@@ -181,11 +181,28 @@ class Emulator {
   // Terminates the currently running title.
   X_STATUS TerminateTitle();
 
-  const std::unique_ptr<vfs::Device> CreateVfsDeviceBasedOnPath(
+  const std::unique_ptr<vfs::Device> CreateVfsDevice(
       const std::filesystem::path& path, const std::string_view mount_path);
 
   X_STATUS MountPath(const std::filesystem::path& path,
                      const std::string_view mount_path);
+
+  enum class FileSignatureType {
+    XEX1,
+    XEX2,
+    ELF,
+    CON,
+    LIVE,
+    PIRS,
+    XISO,
+    ZAR,
+    EXE,
+    Unknown
+  };
+
+  // Determine the executable signature
+  FileSignatureType GetFileSignature(const std::filesystem::path& path);
+
   // Launches a game from the given file path.
   // This will attempt to infer the type of the given file (such as an iso, etc)
   // using heuristics.
@@ -233,8 +250,6 @@ class Emulator {
   enum : uint64_t { EmulatorFlagDisclaimerAcknowledged = 1ULL << 0 };
   static uint64_t GetPersistentEmulatorFlags();
   static void SetPersistentEmulatorFlags(uint64_t new_flags);
-  static std::string CanonicalizeFileExtension(
-      const std::filesystem::path& path);
   static bool ExceptionCallbackThunk(Exception* ex, void* data);
   bool ExceptionCallback(Exception* ex);
 

src/xenia/kernel/user_module.cc

@@ -126,9 +126,12 @@ X_STATUS UserModule::LoadFromMemory(const void* addr, const size_t length) {
   } else if (magic == xe::cpu::kElfSignature) {
     module_format_ = kModuleFormatElf;
   } else {
-    be<uint16_t> magic16;
-    magic16.value = xe::load<uint16_t>(addr);
-    if (magic16 == 0x4D5A) {
+    uint8_t M = xe::load<uint8_t>(addr);
+    uint8_t Z = xe::load<uint8_t>(reinterpret_cast<void*>(
+        reinterpret_cast<uint64_t>(addr) + sizeof(uint8_t)));
+
+    magic = make_fourcc(M, Z, 0, 0);
+    if (magic == kEXESignature) {
       XELOGE("XNA executables are not yet implemented");
       return X_STATUS_NOT_IMPLEMENTED;
     } else {

src/xenia/kernel/user_module.h

@@ -31,6 +31,8 @@ class XThread;
 namespace xe {
 namespace kernel {
 
+constexpr fourcc_t kEXESignature = make_fourcc('M', 'Z', 0, 0);
+
 class UserModule : public XModule {
  public:
   UserModule(KernelState* kernel_state);

src/xenia/vfs/devices/disc_image_device.h

@@ -21,6 +21,8 @@ namespace vfs {
 
 class DiscImageEntry;
 
+constexpr fourcc_t kXSFSignature = make_fourcc(0x58, 0x53, 0x46, 0x1A);
+
 class DiscImageDevice : public Device {
  public:
   DiscImageDevice(const std::string_view mount_path,

src/xenia/vfs/devices/disc_zarchive_device.h

@@ -21,6 +21,11 @@
 namespace xe {
 namespace vfs {
 
+const fourcc_t kZarMagic = make_fourcc((_ZARCHIVE::Footer::kMagic >> 24 & 0xFF),
+                                       (_ZARCHIVE::Footer::kMagic >> 16 & 0xFF),
+                                       (_ZARCHIVE::Footer::kMagic >> 8 & 0xFF),
+                                       (_ZARCHIVE::Footer::kMagic & 0xFF));
+
 class DiscZarchiveEntry;
 
 class DiscZarchiveDevice : public Device {

src/xenia/vfs/devices/xcontent_container_device.h

@@ -22,6 +22,11 @@
 
 namespace xe {
 namespace vfs {
+
+constexpr fourcc_t kLIVESignature = make_fourcc("LIVE");
+constexpr fourcc_t kCONSignature = make_fourcc("CON ");
+constexpr fourcc_t kPIRSSignature = make_fourcc("PIRS");
+
 class XContentContainerDevice : public Device {
  public:
   const static uint32_t kBlockSize = 0x1000;