Use the libretro VFS interface in libretro builds

libretro/CMakeLists.txt

@@ -12,6 +12,19 @@ if(WIN32)
 		LibretroD3D11Context.cpp)
 endif()
 
+set(LIBRETRO_SRCS ${LIBRETRO_SRCS}
+	libretro-common/compat/compat_posix_string.c
+	libretro-common/compat/fopen_utf8.c
+	libretro-common/compat/compat_strl.c
+	libretro-common/encodings/encoding_utf.c
+	libretro-common/file/file_path.c
+	libretro-common/file/file_path_io.c
+	libretro-common/streams/file_stream.c
+	libretro-common/streams/file_stream_transforms.c
+	libretro-common/string/stdstring.c
+	libretro-common/time/rtime.c
+	libretro-common/vfs/vfs_implementation.c)
+
 include_directories(libretro)
 
 add_library(ppsspp_libretro SHARED ${LIBRETRO_SRCS})

libretro/LibretroFileStreamTransforms.h

@@ -0,0 +1,6 @@
+#pragma once
+
+#include <streams/file_stream_transforms.h>
+#undef fopen
+#undef fseek
+#undef ftell

libretro/LibretroVulkanContext.cpp

@@ -13,6 +13,8 @@
 #include <libretro_vulkan.h>
 #include <GPU/Vulkan/VulkanRenderManager.h>
 
+#undef fflush
+
 static VulkanContext *vk;
 
 void vk_libretro_init(VkInstance instance, VkPhysicalDevice gpu, VkSurfaceKHR surface, PFN_vkGetInstanceProcAddr get_instance_proc_addr, const char **required_device_extensions, unsigned num_required_device_extensions, const char **required_device_layers, unsigned num_required_device_layers, const VkPhysicalDeviceFeatures *required_features);

libretro/libretro.cpp

@@ -6,6 +6,7 @@
 #include <vector>
 #include <cstdlib>
 #include <mutex>
+#include <fstream>
 
 #include "Common/CPUDetect.h"
 #include "Common/Log.h"
@@ -401,11 +402,11 @@ void retro_set_environment(retro_environment_t cb)
    update_display_cb.callback = set_variable_visibility;
    environ_cb(RETRO_ENVIRONMENT_SET_CORE_OPTIONS_UPDATE_DISPLAY_CALLBACK, &update_display_cb);
 
-   #ifdef HAVE_LIBRETRO_VFS
-      struct retro_vfs_interface_info vfs_iface_info { 1, nullptr };
-      if (cb(RETRO_ENVIRONMENT_GET_VFS_INTERFACE, &vfs_iface_info))
-         filestream_vfs_init(&vfs_iface_info);
-   #endif
+#ifdef HAVE_LIBRETRO_VFS
+   struct retro_vfs_interface_info vfs_iface_info { 2, nullptr };
+   if (cb(RETRO_ENVIRONMENT_GET_VFS_INTERFACE, &vfs_iface_info))
+      File::InitLibretroVFS(&vfs_iface_info);
+#endif
 }
 
 static int get_language_auto(void)