1 files changed, 129 insertions, 0 deletions
diff --git a/loader/main_efi.c b/loader/main_efi.c
new file mode 100644
index 0000000..070cc16
--- /dev/null
+++ b/loader/main_efi.c
@@ -0,0 +1,129 @@
+#include "loader_efi.h"
+
+#include <stdbool.h>
+#include <stddef.h>
+
+EFI_SYSTEM_TABLE *e_st;
+EFI_BOOT_SERVICES *e_bs;
+EFI_RUNTIME_SERVICES *e_rt;
+
+EFI_HANDLE e_image_handle;
+EFI_LOADED_IMAGE_PROTOCOL *e_loaded_image;
+EFI_SIMPLE_FILE_SYSTEM_PROTOCOL *e_system_partition;
+EFI_GRAPHICS_OUTPUT_PROTOCOL *e_graphics_output;
+EFI_STATUS e_last_error;
+
+extern int _text;
+extern int _data;
+
+static EFI_LOADED_IMAGE_PROTOCOL *open_loaded_image(void);
+static EFI_SIMPLE_FILE_SYSTEM_PROTOCOL *open_system_partition(void);
+static EFI_GRAPHICS_OUTPUT_PROTOCOL *open_graphics_output(void);
+
+EFI_STATUS efi_main(EFI_HANDLE image_handle, EFI_SYSTEM_TABLE *system_table)
+{
+    e_image_handle = image_handle;
+    e_st = system_table;
+    e_bs = e_st->BootServices;
+    e_rt = e_st->RuntimeServices;
+    
+    InitializeLib(e_image_handle, e_st);
+    Print(L"loader starting\r\n");
+    
+    e_loaded_image = open_loaded_image();
+    e_system_partition = open_system_partition();
+    e_graphics_output = open_graphics_output();
+
+    WaitForSingleEvent(e_st->ConIn->WaitForKey, 0);
+    
+    loader_main();
+
+    efi_exit(EFI_ABORTED);
+}
+
+noreturn void efi_exit(EFI_STATUS status)
+{
+    if (EFI_ERROR(status))
+    {
+        Print(L"loader exited: %r\r\n", status);
+    }
+    
+    e_bs->Exit(e_image_handle, status, 0, NULL);
+
+    while (true);
+}
+
+static EFI_LOADED_IMAGE_PROTOCOL *open_loaded_image(void)
+{
+    Print(L"opening loaded image\r\n");
+    
+    EFI_STATUS status;
+    EFI_LOADED_IMAGE_PROTOCOL *image;
+    
+    status = e_bs->OpenProtocol(e_image_handle,
+                                &LoadedImageProtocol,
+                                (void **)&image,
+                                e_image_handle,
+                                NULL,
+                                EFI_OPEN_PROTOCOL_BY_HANDLE_PROTOCOL);
+    
+    if (EFI_ERROR(status))
+    {
+        Print(L"failed opening loaded image\r\n");
+        efi_exit(status);
+    }
+
+    Print(L"image base: 0x%16.0x\r\n", image->ImageBase);
+    Print(L"image .text segment: 0x%16.0x\r\n", &_text);
+    Print(L"image .data segment: 0x%16.0x\r\n", &_data);
+    
+    return image;
+}
+
+static EFI_SIMPLE_FILE_SYSTEM_PROTOCOL *open_system_partition(void)
+{
+    Print(L"opening system partition\r\n");
+    
+    EFI_STATUS status;
+    EFI_SIMPLE_FILE_SYSTEM_PROTOCOL *partition;
+    
+    status = e_bs->OpenProtocol(e_loaded_image->DeviceHandle,
+                               &FileSystemProtocol,
+                               (void **)&partition,
+                               e_image_handle,
+                               NULL,
+                               EFI_OPEN_PROTOCOL_BY_HANDLE_PROTOCOL);
+
+    if (EFI_ERROR(status))
+    {
+        Print(L"failed opening system partition\r\n");
+        efi_exit(status);
+    }
+    
+    Print(L"opened system partition\r\n");
+    
+    return partition;
+}
+
+static EFI_GRAPHICS_OUTPUT_PROTOCOL *open_graphics_output(void)
+{
+    EFI_STATUS status;
+    EFI_GRAPHICS_OUTPUT_PROTOCOL *graphics;
+
+    Print(L"opening graphics output\r\n");  
+ 
+    status = e_bs->LocateProtocol(&GraphicsOutputProtocol,
+                                  NULL,
+                                  (VOID **)&graphics);
+
+    if (EFI_ERROR(status))
+    {
+        Print(L"failed opening graphics output: %r\r\n", status);
+        return NULL;
+    }
+
+    Print(L"graphics output opened\r\n");
+
+    return graphics;
+}
+