core/file.c


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/*
 * Copyright (c) 2026, Apollo Telephone Laboratories.
 * Provided under the BSD-3 clause.
 */

#include <sboot/file.h>
#include <sboot/fwi.h>

EFI_STATUS
FileGetVolume(IN EFI_HANDLE ImageHandle, OUT EFI_FILE_HANDLE *Handle)
{
    EFI_LOADED_IMAGE *LoadedImage = NULL;
    EFI_SIMPLE_FILE_SYSTEM_PROTOCOL *IoVolume;
    EFI_GUID LipGuid = EFI_LOADED_IMAGE_PROTOCOL_GUID;
    EFI_GUID FsGuid = EFI_SIMPLE_FILE_SYSTEM_PROTOCOL_GUID;
    EFI_FILE_HANDLE Volume;
    EFI_STATUS Status;

    Status = FwiHandleProtocol(
        ImageHandle,
        &LipGuid,
        (VOID **)&LoadedImage
    );

    if (EFI_ERROR(Status)) {
        Print(L"fatal: could not get loaded image\n");
        return Status;
    }

    Status = FwiHandleProtocol(
        LoadedImage->DeviceHandle,
        &FsGuid,
        (VOID *)&IoVolume
    );

    if (EFI_ERROR(Status)) {
        Print(L"fatal: could not I/O volume\n");
        return Status;
    }

    Status = uefi_call_wrapper(
        IoVolume->OpenVolume,
        2,
        IoVolume,
        &Volume
    );

    if (EFI_ERROR(Status)) {
        Print(L"fatal: failed to get volume\n");
        return Status;
    }

    *Handle = Volume;
    return EFI_SUCCESS;
}