lib/allocator.h

   1 /* Memory allocators such as malloc+free.
   2
   3    Copyright (C) 2011 Free Software Foundation, Inc.
   4
   5    This program is free software: you can redistribute it and/or modify
   6    it under the terms of the GNU General Public License as published by
   7    the Free Software Foundation; either version 3 of the License, or
   8    (at your option) any later version.
   9
  10    This program 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
  13    GNU General Public License for more details.
  14
  15    You should have received a copy of the GNU General Public License
  16    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  17
  18 /* Written by Paul Eggert.  */
  19
  20 #ifndef _GL_ALLOCATOR_H
  21 #define _GL_ALLOCATOR_H
  22
  23 #include <stddef.h>
  24
  25 /* An object describing a memory allocator family.  */
  26
  27 struct allocator
  28 {
  29   /* Do not use GCC attributes such as __attribute__ ((malloc)) with
  30      the function types pointed at by these members, because these
  31      attributes do not work with pointers to functions.  See
  32      <http://lists.gnu.org/archive/html/bug-gnulib/2011-04/msg00007.html>.  */
  33
  34   /* Call ALLOCATE to allocate memory, like 'malloc'.  On failure ALLOCATE
  35      should return NULL, though not necessarily set errno.  When given
  36      a zero size it may return NULL even if successful.  */
  37   void *(*allocate) (size_t);
  38
  39   /* If nonnull, call REALLOCATE to reallocate memory, like 'realloc'.
  40      On failure REALLOCATE should return NULL, though not necessarily set
  41      errno.  When given a zero size it may return NULL even if
  42      successful.  */
  43   void *(*reallocate) (void *, size_t);
  44
  45   /* Call FREE to free memory, like 'free'.  */
  46   void (*free) (void *);
  47
  48   /* If nonnull, call DIE if MALLOC or REALLOC fails.  DIE should not
  49      return.  DIE can be used by code that detects memory overflow
  50      while calculating sizes to be passed to MALLOC or REALLOC.  */
  51   void (*die) (void);
  52 };
  53
  54 /* An allocator using the stdlib functions and a null DIE function.  */
  55 extern struct allocator const stdlib_allocator;
  56
  57 #endif /* _GL_ALLOCATOR_H */