tools/lib/cmdline.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * From lib/cmdline.c
   4  */
   5 #include <stdlib.h>
   6
   7 #if __has_attribute(__fallthrough__)
   8 # define fallthrough                    __attribute__((__fallthrough__))
   9 #else
  10 # define fallthrough                    do {} while (0)  /* fallthrough */
  11 #endif
  12
  13 unsigned long long memparse(const char *ptr, char **retptr)
  14 {
  15         char *endptr;   /* local pointer to end of parsed string */
  16
  17         unsigned long long ret = strtoll(ptr, &endptr, 0);
  18
  19         switch (*endptr) {
  20         case 'E':
  21         case 'e':
  22                 ret <<= 10;
  23                 fallthrough;
  24         case 'P':
  25         case 'p':
  26                 ret <<= 10;
  27                 fallthrough;
  28         case 'T':
  29         case 't':
  30                 ret <<= 10;
  31                 fallthrough;
  32         case 'G':
  33         case 'g':
  34                 ret <<= 10;
  35                 fallthrough;
  36         case 'M':
  37         case 'm':
  38                 ret <<= 10;
  39                 fallthrough;
  40         case 'K':
  41         case 'k':
  42                 ret <<= 10;
  43                 endptr++;
  44                 fallthrough;
  45         default:
  46                 break;
  47         }
  48
  49         if (retptr)
  50                 *retptr = endptr;
  51
  52         return ret;
  53 }