drivers/partition/gpt.c

   1 /*
   2  * Copyright (c) 2016-2017, ARM Limited and Contributors. All rights reserved.
   3  *
   4  * SPDX-License-Identifier: BSD-3-Clause
   5  */
   6
   7 #include <assert.h>
   8 #include <debug.h>
   9 #include <errno.h>
  10 #include <gpt.h>
  11 #include <string.h>
  12 #include <utils.h>
  13
  14 static int unicode_to_ascii(unsigned short *str_in, unsigned char *str_out)
  15 {
  16         uint8_t *name;
  17         int i;
  18
  19         assert((str_in != NULL) && (str_out != NULL));
  20
  21         name = (uint8_t *)str_in;
  22
  23         assert(name[0] != '\0');
  24
  25         /* check whether the unicode string is valid */
  26         for (i = 1; i < (EFI_NAMELEN << 1); i += 2) {
  27                 if (name[i] != '\0')
  28                         return -EINVAL;
  29         }
  30         /* convert the unicode string to ascii string */
  31         for (i = 0; i < (EFI_NAMELEN << 1); i += 2) {
  32                 str_out[i >> 1] = name[i];
  33                 if (name[i] == '\0')
  34                         break;
  35         }
  36         return 0;
  37 }
  38
  39 int parse_gpt_entry(gpt_entry_t *gpt_entry, partition_entry_t *entry)
  40 {
  41         int result;
  42
  43         assert((gpt_entry != NULL) && (entry != NULL));
  44
  45         if ((gpt_entry->first_lba == 0) && (gpt_entry->last_lba == 0)) {
  46                 return -EINVAL;
  47         }
  48
  49         zeromem(entry, sizeof(partition_entry_t));
  50         result = unicode_to_ascii(gpt_entry->name, (uint8_t *)entry->name);
  51         if (result != 0) {
  52                 return result;
  53         }
  54         entry->start = (uint64_t)gpt_entry->first_lba * PARTITION_BLOCK_SIZE;
  55         entry->length = (uint64_t)(gpt_entry->last_lba -
  56                                    gpt_entry->first_lba + 1) *
  57                         PARTITION_BLOCK_SIZE;
  58         return 0;
  59 }