utils-lib.c

   1 #include "kerncompat.h"
   2 #include <unistd.h>
   3 #include <stdlib.h>
   4 #include <limits.h>
   5
   6 #if BTRFS_FLAT_INCLUDES
   7 #else
   8 #endif /* BTRFS_FLAT_INCLUDES */
   9
  10 /*
  11  * This function should be only used when parsing command arg, it won't return
  12  * error to its caller and rather exit directly just like usage().
  13  */
  14 u64 arg_strtou64(const char *str)
  15 {
  16         u64 value;
  17         char *ptr_parse_end = NULL;
  18
  19         value = strtoull(str, &ptr_parse_end, 0);
  20         if (ptr_parse_end && *ptr_parse_end != '\0') {
  21                 fprintf(stderr, "ERROR: %s is not a valid numeric value.\n",
  22                         str);
  23                 exit(1);
  24         }
  25
  26         /*
  27          * if we pass a negative number to strtoull, it will return an
  28          * unexpected number to us, so let's do the check ourselves.
  29          */
  30         if (str[0] == '-') {
  31                 fprintf(stderr, "ERROR: %s: negative value is invalid.\n",
  32                         str);
  33                 exit(1);
  34         }
  35         if (value == ULLONG_MAX) {
  36                 fprintf(stderr, "ERROR: %s is too large.\n", str);
  37                 exit(1);
  38         }
  39         return value;
  40 }