1  /* Internal header file for __libc_supported_implementations.
       2     Copyright (C) 2012-2023 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 _IFUNC_IMPL_LIST_H
      20  #define _IFUNC_IMPL_LIST_H	1
      21  
      22  #include <stdbool.h>
      23  #include <stddef.h>
      24  
      25  struct libc_ifunc_impl
      26  {
      27    /* The name of function to be tested.  */
      28    const char *name;
      29    /* The address of function to be tested.  */
      30    void (*fn) (void);
      31    /* True if this implementation is usable on this machine.  */
      32    bool usable;
      33  };
      34  
      35  /* Add an IFUNC implementation, IMPL, for function FUNC, to ARRAY with
      36     USABLE at index I and advance I by one.  */
      37  #define IFUNC_IMPL_ADD(array, max, func, usable, impl) \
      38    extern __typeof (func) impl attribute_hidden; \
      39    if (n < max) (array)[n++] = (struct libc_ifunc_impl) { #impl, (void (*) (void)) impl, (usable) };
      40  
      41  /* Return the number of IFUNC implementations, N, for function FUNC if
      42     string NAME matches FUNC.  */
      43  #define IFUNC_IMPL(max, name, func, ...) \
      44    if (strcmp (name, #func) == 0) \
      45      { size_t n = 0;\
      46        __VA_ARGS__; \
      47        return n; \
      48      }
      49  
      50  /* Fill ARRAY of MAX elements with IFUNC implementations for function
      51     NAME and return the number of valid entries.  */
      52  extern size_t __libc_ifunc_impl_list (const char *name,
      53  				      struct libc_ifunc_impl *array,
      54  				      size_t max);
      55  
      56  #endif /* ifunc-impl-list.h */