[BOOT] Add boot manager headers

BOOT/ENVIRON/APP/BOOTMGR/EFI/efientry.c

@@ -14,6 +14,7 @@ Abstract:
 --*/
 
 #include "bootmgr.h"
+#include "efilib.h"
 
 EFI_STATUS
 EFIAPI

BOOT/ENVIRON/APP/BOOTMGR/bootmgr.c

@@ -38,7 +38,9 @@ Return Value:
 --*/
 
 {
-    /* TODO: Implement BmMain() */
+    (VOID)Parameters;
+
+    /* Not implemented */
 
     return STATUS_SUCCESS;
 }

BOOT/ENVIRON/INC/bootmgr.h

@@ -0,0 +1,34 @@
+/*++
+
+Copyright (c) 2024, Quinn Stephens.
+Provided under the BSD 3-Clause license.
+
+Module Name:
+
+   bootmgr.h
+
+Abstract:
+
+   Boot manager definitions.
+
+--*/
+
+#ifndef _BOOTMGR_H
+#define _BOOTMGR_H
+
+#include <nt.h>
+
+#define BOOT_APPLICATION_PARAMETERS_SIGNATURE 0x50504120544f4f42 /* "BOOT APP" */
+#define BOOT_APPLICATION_PARAMETERS_VERSION   2
+
+typedef struct {
+    ULONGLONG Signature;
+    ULONG Version;
+} BOOT_APPLICATION_PARAMETERS, *PBOOT_APPLICATION_PARAMETERS;
+
+NTSTATUS
+BmMain (
+    IN PBOOT_APPLICATION_PARAMETERS Parameters
+    );
+
+#endif

BOOT/ENVIRON/INC/efilib.h

@@ -0,0 +1,34 @@
+/*++
+
+Copyright (c) 2024, Quinn Stephens.
+Provided under the BSD 3-Clause license.
+
+Module Name:
+
+   efilib.h
+
+Abstract:
+
+    Boot manager EFI library definitions.
+
+--*/
+
+#ifndef _EFILIB_H
+#define _EFILIB_H
+
+#include <nt.h>
+#include "bootmgr.h"
+#include "efi.h"
+
+PBOOT_APPLICATION_PARAMETERS
+EfiInitCreateInputParameters (
+    IN EFI_HANDLE ImageHandle,
+    IN EFI_SYSTEM_TABLE *SystemTable
+    );
+
+EFI_STATUS
+EfiGetEfiStatusCode (
+    IN NTSTATUS Status
+    );
+
+#endif

BOOT/ENVIRON/LIB/EFI/efiinit.c

@@ -0,0 +1,58 @@
+/*++
+
+Copyright (c) 2024, Quinn Stephens.
+Provided under the BSD 3-Clause license.
+
+Module Name:
+
+   efiinit.c
+
+Abstract:
+
+   Provides EFI initialization utilities.
+
+--*/
+
+#include "bootmgr.h"
+#include "efi.h"
+
+UCHAR EfiInitScratch[2048];
+
+PBOOT_APPLICATION_PARAMETERS
+EfiInitCreateInputParameters (
+    IN EFI_HANDLE ImageHandle,
+    IN EFI_SYSTEM_TABLE *SystemTable
+    )
+
+/*++
+
+Routine Description:
+
+    Creates the input parameter structure for the boot application.
+
+Arguments:
+
+    ImageHandle - Handle for the boot manager image.
+
+    SystemTable - Pointer to the EFI system table.
+
+Return Value:
+
+    Pointer to parameter structure on success or NULL on failure.
+
+--*/
+
+{
+    ULONG ScratchUsed = 0;
+    PBOOT_APPLICATION_PARAMETERS InputParameters;
+
+    (VOID)ImageHandle;
+    (VOID)SystemTable;
+
+    InputParameters = (PBOOT_APPLICATION_PARAMETERS)(&EfiInitScratch[ScratchUsed]);
+    InputParameters->Signature = BOOT_APPLICATION_PARAMETERS_SIGNATURE;
+    InputParameters->Version = BOOT_APPLICATION_PARAMETERS_VERSION;
+    ScratchUsed += sizeof(BOOT_APPLICATION_PARAMETERS);
+
+    return InputParameters;
+}

BOOT/ENVIRON/LIB/EFI/efistatus.c

@@ -14,6 +14,7 @@ Abstract:
 --*/
 
 #include "bootmgr.h"
+#include "efi.h"
 
 EFI_STATUS
 EfiGetEfiStatusCode (