lib/efi_loader/efi_device_path_to_text.c

   1 /*
   2  *  EFI device path interface
   3  *
   4  *  Copyright (c) 2017 Heinrich Schuchardt
   5  *
   6  *  SPDX-License-Identifier:     GPL-2.0+
   7  */
   8
   9 #include <common.h>
  10 #include <efi_loader.h>
  11
  12 #define MEDIA_DEVICE_PATH 4
  13 #define FILE_PATH_MEDIA_DEVICE_PATH 4
  14
  15 const efi_guid_t efi_guid_device_path_to_text_protocol =
  16                 EFI_DEVICE_PATH_TO_TEXT_PROTOCOL_GUID;
  17
  18 uint16_t *efi_convert_device_node_to_text(
  19                 struct efi_device_path_protocol *device_node,
  20                 bool display_only,
  21                 bool allow_shortcuts)
  22 {
  23         EFI_ENTRY("%p, %d, %d", device_node, display_only, allow_shortcuts);
  24
  25         EFI_EXIT(EFI_UNSUPPORTED);
  26         return NULL;
  27 }
  28
  29 uint16_t *efi_convert_device_path_to_text(
  30                 struct efi_device_path_protocol *device_path,
  31                 bool display_only,
  32                 bool allow_shortcuts)
  33 {
  34         EFI_ENTRY("%p, %d, %d", device_path, display_only, allow_shortcuts);
  35
  36         unsigned long buffer_size;
  37         efi_status_t r;
  38         uint16_t *buffer = NULL;
  39
  40         switch (device_path->type) {
  41         case MEDIA_DEVICE_PATH:
  42                 switch (device_path->sub_type) {
  43                 case FILE_PATH_MEDIA_DEVICE_PATH:
  44                         buffer_size = device_path->length - 4;
  45                         r = efi_allocate_pool(EFI_ALLOCATE_ANY_PAGES,
  46                                               buffer_size, (void **) &buffer);
  47                         if (r == EFI_SUCCESS)
  48                                 memcpy(buffer, device_path->data, buffer_size);
  49                         break;
  50                 }
  51         }
  52
  53         if (buffer) {
  54                 EFI_EXIT(EFI_SUCCESS);
  55         } else {
  56                 debug("type %d, subtype %d\n",
  57                       device_path->type, device_path->sub_type);
  58                 EFI_EXIT(EFI_UNSUPPORTED);
  59         }
  60
  61         return buffer;
  62 }
  63
  64 const struct efi_device_path_to_text_protocol efi_device_path_to_text = {
  65         .convert_device_node_to_text = efi_convert_device_node_to_text,
  66         .convert_device_path_to_text = efi_convert_device_path_to_text,
  67 };