wrapper/kstrtox.h

   1 #ifndef _LTTNG_WRAPPER_KSTRTOX_H
   2 #define _LTTNG_WRAPPER_KSTRTOX_H
   3
   4 /*
   5  * wrapper/kstrtox.h
   6  *
   7  * Copyright (C) 2015 Michael Jeanson <mjeanson@efficios.com>
   8  *
   9  * This library is free software; you can redistribute it and/or
  10  * modify it under the terms of the GNU Lesser General Public
  11  * License as published by the Free Software Foundation; only
  12  * version 2.1 of the License.
  13  *
  14  * This library is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  17  * Lesser General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU Lesser General Public
  20  * License along with this library; if not, write to the Free Software
  21  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  22  */
  23
  24 #include <linux/version.h>
  25
  26 #if (LINUX_VERSION_CODE < KERNEL_VERSION(3,0,0))
  27
  28 #include <linux/uaccess.h>
  29
  30 /* Excludes final \0. */
  31 #define LTTNG_MAX_UINT_CHAR 10
  32
  33 static inline
  34 int __must_check lttng_kstrtouint_from_user(const char __user *ubuf,
  35                 size_t count, unsigned int base, unsigned int *res)
  36 {
  37         unsigned int _res;
  38         char kbuf[LTTNG_MAX_UINT_CHAR + 1], *endptr;
  39
  40         memset(kbuf, 0, sizeof(kbuf));
  41         if (copy_from_user(kbuf, ubuf, min_t(size_t, LTTNG_MAX_UINT_CHAR, count)))
  42                 return -EFAULT;
  43
  44         _res = simple_strtoul(kbuf, &endptr, base);
  45         if (!endptr)
  46                 return -EINVAL;
  47
  48         *res = _res;
  49         return 0;
  50 }
  51 #else
  52 static inline
  53 int __must_check lttng_kstrtouint_from_user(const char __user *ubuf,
  54                 size_t count, unsigned int base, unsigned int *res)
  55 {
  56         return kstrtouint_from_user(ubuf, count, base, res);
  57 }
  58 #endif
  59
  60 #endif /* _LTTNG_WRAPPER_KSTRTOX_H */