sysdeps/unix/sysv/linux/sysdep-vdso.h

   1 /* vDSO common definition for Linux.
   2    Copyright (C) 2015-2024 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <https://www.gnu.org/licenses/>.  */
  18
  19 #ifndef SYSDEP_VDSO_LINUX_H
  20 # define SYSDEP_VDSO_LINUX_H
  21
  22 #include <ldsodefs.h>
  23
  24 #ifndef INTERNAL_VSYSCALL_CALL
  25 # define INTERNAL_VSYSCALL_CALL(funcptr, nr, args...)                         \
  26      funcptr (args)
  27 #endif
  28
  29 #define INLINE_VSYSCALL(name, nr, args...)                                    \
  30   ({                                                                          \
  31     __label__ out;                                                            \
  32     __label__ iserr;                                                          \
  33     long int sc_ret;                                                          \
  34                                                                               \
  35     __typeof (GLRO(dl_vdso_##name)) vdsop = GLRO(dl_vdso_##name);             \
  36     if (vdsop != NULL)                                                        \
  37       {                                                                       \
  38         sc_ret = INTERNAL_VSYSCALL_CALL (vdsop, nr, ##args);                  \
  39         if (!INTERNAL_SYSCALL_ERROR_P (sc_ret))                               \
  40           goto out;                                                           \
  41         if (INTERNAL_SYSCALL_ERRNO (sc_ret) != ENOSYS)                        \
  42           goto iserr;                                                         \
  43       }                                                                       \
  44                                                                               \
  45     sc_ret = INTERNAL_SYSCALL_CALL (name, ##args);                            \
  46     if (INTERNAL_SYSCALL_ERROR_P (sc_ret))                                    \
  47       {                                                                       \
  48       iserr:                                                                  \
  49         __set_errno (INTERNAL_SYSCALL_ERRNO (sc_ret));                        \
  50         sc_ret = -1L;                                                         \
  51       }                                                                       \
  52   out:                                                                        \
  53     sc_ret;                                                                   \
  54   })
  55
  56 #define INTERNAL_VSYSCALL(name, nr, args...)                                  \
  57   ({                                                                          \
  58     long int sc_ret = -ENOSYS;                                                \
  59                                                                               \
  60     __typeof (GLRO(dl_vdso_##name)) vdsop = GLRO(dl_vdso_##name);             \
  61     if (vdsop != NULL)                                                        \
  62         sc_ret = INTERNAL_VSYSCALL_CALL (vdsop, nr, ##args);                  \
  63     if (sc_ret == -ENOSYS)                                                    \
  64         sc_ret = INTERNAL_SYSCALL_CALL (name, ##args);                        \
  65     sc_ret;                                                                   \
  66   })
  67
  68 #endif /* SYSDEP_VDSO_LINUX_H  */