iOS runtime impl progress

Source/Engine/Platform/File.h

@@ -4,8 +4,10 @@
 
 #if PLATFORM_WINDOWS || PLATFORM_UWP || PLATFORM_XBOX_ONE || PLATFORM_XBOX_SCARLETT
 #include "Win32/Win32File.h"
-#elif PLATFORM_LINUX || PLATFORM_PS4 || PLATFORM_PS5 || PLATFORM_MAC || PLATFORM_IOS
+#elif PLATFORM_LINUX || PLATFORM_PS4 || PLATFORM_PS5 || PLATFORM_MAC
 #include "Unix/UnixFile.h"
+#elif PLATFORM_IOS
+#include "iOS/iOSFile.h"
 #elif PLATFORM_ANDROID
 #include "Android/AndroidFile.h"
 #elif PLATFORM_SWITCH

Source/Engine/Platform/FileSystem.h

@@ -23,7 +23,7 @@
 #elif PLATFORM_MAC
 #include "Mac/MacFileSystem.h"
 #elif PLATFORM_IOS
-#include "Apple/AppleFileSystem.h"
+#include "iOS/iOSFileSystem.h"
 #else
 #error Missing File System implementation!
 #endif

Source/Engine/Platform/Types.h

@@ -260,12 +260,12 @@ class UnixCriticalSection;
 typedef UnixCriticalSection CriticalSection;
 class UnixConditionVariable;
 typedef UnixConditionVariable ConditionVariable;
-class AppleFileSystem;
+class iOSFileSystem;
-typedef AppleFileSystem FileSystem;
+typedef iOSFileSystem FileSystem;
 class FileSystemWatcherBase;
 typedef FileSystemWatcherBase FileSystemWatcher;
-class UnixFile;
+class iOSFile;
-typedef UnixFile File;
+typedef iOSFile File;
 class iOSPlatform;
 typedef iOSPlatform Platform;
 class AppleThread;

Source/Engine/Platform/iOS/iOSFile.h

@@ -0,0 +1,23 @@
+// Copyright (c) 2012-2023 Wojciech Figat. All rights reserved.
+
+#pragma once
+
+#if PLATFORM_IOS
+
+#include "Engine/Platform/Unix/UnixFile.h"
+
+/// <summary>
+/// iOS platform file object implementation.
+/// </summary>
+class FLAXENGINE_API iOSFile : public UnixFile
+{
+public:
+    iOSFile(int32 handle)
+        : UnixFile(handle)
+    {
+    }
+
+    static iOSFile* Open(const StringView& path, FileMode mode, FileAccess access = FileAccess::ReadWrite, FileShare share = FileShare::None);
+};
+
+#endif

Source/Engine/Platform/iOS/iOSFileSystem.h

@@ -0,0 +1,20 @@
+// Copyright (c) 2012-2023 Wojciech Figat. All rights reserved.
+
+#pragma once
+
+#if PLATFORM_IOS
+
+#include "Engine/Platform/Apple/AppleFileSystem.h"
+
+/// <summary>
+/// iOS platform implementation of filesystem service.
+/// </summary>
+class FLAXENGINE_API iOSFileSystem : public AppleFileSystem
+{
+public:
+    static bool FileExists(const StringView& path);
+    static uint64 GetFileSize(const StringView& path);
+    static bool IsReadOnly(const StringView& path);
+};
+
+#endif

Source/Engine/Platform/iOS/iOSPlatform.cpp

@@ -4,6 +4,8 @@
 
 #include "iOSPlatform.h"
 #include "iOSWindow.h"
+#include "iOSFile.h"
+#include "iOSFileSystem.h"
 #include "Engine/Core/Log.h"
 #include "Engine/Core/Types/String.h"
 #include "Engine/Core/Collections/Array.h"
@@ -13,12 +15,20 @@
 #include "Engine/Platform/Window.h"
 #include "Engine/Platform/WindowsManager.h"
 #include "Engine/Threading/Threading.h"
+#include "Engine/Engine/Engine.h"
+#include "Engine/Engine/Globals.h"
 #include <UIKit/UIKit.h>
 #include <sys/utsname.h>
 
 int32 Dpi = 96;
 Guid DeviceId;
 
+// Used by iOS project in XCode to run engine (see main.m)
+extern "C" FLAXENGINE_API int FlaxEngineMain()
+{
+    return Engine::Main(TEXT(""));
+}
+
 DialogResult MessageBox::Show(Window* parent, const StringView& text, const StringView& caption, MessageBoxButtons buttons, MessageBoxIcon icon)
 {
 	NSString* title = (NSString*)AppleUtils::ToString(caption);
@@ -38,6 +48,40 @@ DialogResult MessageBox::Show(Window* parent, const StringView& text, const Stri
     return DialogResult::OK;
 }
 
+#define IOS_FALLBACK_PATH(path) (Globals::ProjectFolder / StringUtils::GetFileName(path))
+
+iOSFile* iOSFile::Open(const StringView& path, FileMode mode, FileAccess access, FileShare share)
+{
+    iOSFile* file = (iOSFile*)UnixFile::Open(path, mode, access, share);
+    if (!file && mode == FileMode::OpenExisting)
+    {
+        // Fallback to file placed side-by-side with application
+        file = (iOSFile*)UnixFile::Open(IOS_FALLBACK_PATH(path), mode, access, share);
+    }
+    return file;
+}
+
+bool iOSFileSystem::FileExists(const StringView& path)
+{
+    return AppleFileSystem::FileExists(path) || AppleFileSystem::FileExists(IOS_FALLBACK_PATH(path));
+}
+
+uint64 iOSFileSystem::GetFileSize(const StringView& path)
+{
+    if (AppleFileSystem::FileExists(path))
+        return AppleFileSystem::GetFileSize(path);
+    return AppleFileSystem::GetFileSize(IOS_FALLBACK_PATH(path));
+}
+
+bool iOSFileSystem::IsReadOnly(const StringView& path)
+{
+    if (AppleFileSystem::FileExists(path))
+        return AppleFileSystem::IsReadOnly(path);
+    return AppleFileSystem::IsReadOnly(IOS_FALLBACK_PATH(path));
+}
+
+#undef IOS_FALLBACK_PATH
+
 bool iOSPlatform::Init()
 {
     if (ApplePlatform::Init())

Source/Engine/Scripting/Runtime/DotNet.cpp

@@ -1782,6 +1782,7 @@ static MonoAssembly* OnMonoAssemblyPreloadHook(MonoAssemblyName* aname, char** a
 }
 
 #if 0
+
 static unsigned char* OnMonoLoadAOT(MonoAssembly* assembly, int size, void* user_data, void** out_handle)
 {
     MonoAssemblyName* assemblyName = mono_assembly_get_name(assembly);
@@ -1800,6 +1801,57 @@ static void OnMonoFreeAOT(MonoAssembly* assembly, int size, void* user_data, voi
     LOG(Info, "Free AOT data for C# assembly {0}", String(assemblyNameStr));
 #endif
 }
+
+#endif
+
+#if PLATFORM_IOS
+
+#include "Engine/Engine/Globals.h"
+#include <mono/utils/mono-dl-fallback.h>
+#include <dlfcn.h>
+
+static void* OnMonoDlFallbackLoad(const char* name, int flags, char** err, void* user_data)
+{
+    const String fileName = StringUtils::GetFileName(String(name));
+#if DOTNET_HOST_MONO_DEBUG
+    LOG(Info, "Loading dynamic library {0}", fileName);
+#endif
+    int dlFlags = 0;
+    if (flags & MONO_DL_GLOBAL && !(flags & MONO_DL_LOCAL))
+		dlFlags |= RTLD_GLOBAL;
+	else
+		dlFlags |= RTLD_LOCAL;
+	if (flags & MONO_DL_LAZY)
+		dlFlags |= RTLD_LAZY;
+	else
+		dlFlags |= RTLD_NOW;
+    void* result = dlopen(name, dlFlags);
+    if (!result)
+    {
+        // Try Frameworks location on iOS
+        String path = Globals::ProjectFolder / TEXT("Frameworks") / fileName;
+        if (!path.EndsWith(TEXT(".dylib")))
+            path += TEXT(".dylib");
+        result = dlopen(StringAsANSI<>(*path).Get(), dlFlags);
+        if (!result)
+        {
+            LOG(Error, "Failed to load dynamic libary {0}", String(name));
+        }
+    }
+    return result;
+}
+
+static void* OnMonoDlFallbackSymbol(void* handle, const char* name, char** err, void* user_data)
+{
+	return dlsym(handle, name);
+}
+
+static void* OnMonoDlFallbackClose(void* handle, void* user_data)
+{
+	dlclose(handle);
+    return 0;
+}
+
 #endif
 
 bool InitHostfxr()
@@ -1816,6 +1868,12 @@ bool InitHostfxr()
     mono_jit_set_aot_mode(USE_MONO_AOT_MODE);
 #endif
     
+    // Platform-specific setup
+#if PLATFORM_IOS
+    setenv("MONO_AOT_MODE", "aot", 1);
+    setenv("DOTNET_SYSTEM_GLOBALIZATION_INVARIANT", "1", 1);
+#endif
+
 #ifdef USE_MONO_AOT_MODULE
     // Load AOT module
     const DateTime aotModuleLoadStartTime = DateTime::Now();
@@ -1916,6 +1974,9 @@ bool InitHostfxr()
 #if 0
     mono_install_load_aot_data_hook(OnMonoLoadAOT, OnMonoFreeAOT, nullptr);
 #endif
+#if PLATFORM_IOS
+    mono_dl_fallback_register(OnMonoDlFallbackLoad, OnMonoDlFallbackSymbol, OnMonoDlFallbackClose, nullptr);
+#endif
 
     // Init managed runtime
 #if PLATFORM_ANDROID || PLATFORM_IOS

Source/Engine/Scripting/Scripting.cpp

@@ -351,6 +351,12 @@ bool Scripting::LoadBinaryModules(const String& path, const String& projectFolde
                         {
                             nativePath = String(StringUtils::GetDirectoryName(Platform::GetExecutableFilePath())) / StringUtils::GetFileName(nativePath);
                         }
+#elif PLATFORM_IOS
+                        // iOS uses Frameworks folder with native binaries
+                        if (!FileSystem::FileExists(nativePath))
+                        {
+                            nativePath = Globals::ProjectFolder / TEXT("Frameworks") / StringUtils::GetFileName(nativePath);
+                        }
 #endif
                         auto library = Platform::LoadLibrary(nativePath.Get());
                         if (!library)