lib/amemxfrm.h

   1 /* Locale dependent memory area transformation for comparison.
   2    Copyright (C) 2009-2024 Free Software Foundation, Inc.
   3
   4    This file is free software: you can redistribute it and/or modify
   5    it under the terms of the GNU Lesser General Public License as
   6    published by the Free Software Foundation; either version 2.1 of the
   7    License, or (at your option) any later version.
   8
   9    This file is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12    GNU Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public License
  15    along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
  16
  17 #ifndef AMEMXFRM_H
  18 #define AMEMXFRM_H
  19
  20 #include <stddef.h>
  21
  22 #ifdef __cplusplus
  23 extern "C" {
  24 #endif
  25
  26
  27 /* Generalization of strxfrm() to strings with embedded NUL bytes.  */
  28
  29 /* Transform the memory area [S..S+N-1] to a memory area, in such a way that
  30    comparing (S1,N1) and (S2,N2) with memcoll() is equivalent to comparing
  31    amemxfrm(S1,N1) and amemxfrm(S2,N2) with memcmp2().
  32    The byte S[N] may be temporarily overwritten by this function, but will be
  33    restored before this function returns.
  34    The result of this function depends on the LC_COLLATE category of the
  35    current locale.
  36    If successful: If resultbuf is not NULL and the result fits into *lengthp
  37    bytes, it is put in resultbuf, and resultbuf is returned.  Otherwise, a
  38    freshly allocated string is returned.  In both cases, *lengthp is set to the
  39    length of the returned string.
  40    Upon failure, return NULL, with errno set.  */
  41 extern char * amemxfrm (char *restrict s, size_t n,
  42                         char *restrict resultbuf, size_t *lengthp);
  43
  44
  45 #ifdef __cplusplus
  46 }
  47 #endif
  48
  49 #endif /* AMEMXFRM_H */