lib/safe-alloc.h

   1 /* safe-alloc.h: safer memory allocation
   2
   3    Copyright (C) 2009-2019 Free Software Foundation, Inc.
   4
   5    This program is free software: you can redistribute it and/or modify it
   6    under the terms of the GNU General Public License as published by the
   7    Free Software Foundation; either version 3 of the License, or any
   8    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 <https://www.gnu.org/licenses/>.  */
  17
  18 /* Written by Daniel Berrange <berrange@redhat.com>, 2008 */
  19
  20 #ifndef SAFE_ALLOC_H_
  21 # define SAFE_ALLOC_H_
  22
  23 # include <stdlib.h>
  24
  25 #ifndef __GNUC_PREREQ
  26 # if defined __GNUC__ && defined __GNUC_MINOR__
  27 #  define __GNUC_PREREQ(maj, min)                                       \
  28   ((__GNUC__ << 16) + __GNUC_MINOR__ >= ((maj) << 16) + (min))
  29 # else
  30 #  define __GNUC_PREREQ(maj, min) 0
  31 # endif
  32 #endif
  33
  34 # ifndef _GL_ATTRIBUTE_RETURN_CHECK
  35 #  if __GNUC_PREREQ (3, 4)
  36 #   define _GL_ATTRIBUTE_RETURN_CHECK __attribute__((__warn_unused_result__))
  37 #  else
  38 #   define _GL_ATTRIBUTE_RETURN_CHECK
  39 #  endif
  40 # endif
  41
  42 /* Don't call these directly - use the macros below */
  43 int
  44 safe_alloc_alloc_n (void *ptrptr, size_t size, size_t count, int zeroed)
  45   _GL_ATTRIBUTE_RETURN_CHECK;
  46
  47 int
  48 safe_alloc_realloc_n (void *ptrptr, size_t size, size_t count)
  49   _GL_ATTRIBUTE_RETURN_CHECK;
  50
  51 /**
  52  * ALLOC:
  53  * @ptr: pointer to hold address of allocated memory
  54  *
  55  * Allocate sizeof(*ptr) bytes of memory and store
  56  * the address of allocated memory in 'ptr'. Fill the
  57  * newly allocated memory with zeros.
  58  *
  59  * Return -1 on failure to allocate, zero on success
  60  */
  61 # define ALLOC(ptr)                                     \
  62   safe_alloc_alloc_n (&(ptr), sizeof (*(ptr)), 1, 1)
  63
  64 /**
  65  * ALLOC_N:
  66  * @ptr: pointer to hold address of allocated memory
  67  * @count: number of elements to allocate
  68  *
  69  * Allocate an array of 'count' elements, each sizeof(*ptr)
  70  * bytes long and store the address of allocated memory in
  71  * 'ptr'. Fill the newly allocated memory with zeros.
  72  *
  73  * Return -1 on failure, 0 on success
  74  */
  75 # define ALLOC_N(ptr, count)                                    \
  76   safe_alloc_alloc_n (&(ptr), sizeof (*(ptr)), (count), 1)
  77
  78 /**
  79  * ALLOC_N_UNINITIALIZED:
  80  * @ptr: pointer to hold address of allocated memory
  81  * @count: number of elements to allocate
  82  *
  83  * Allocate an array of 'count' elements, each sizeof(*ptr)
  84  * bytes long and store the address of allocated memory in
  85  * 'ptr'. Do not initialize the new memory at all.
  86  *
  87  * Return -1 on failure to allocate, zero on success
  88  */
  89 # define ALLOC_N_UNINITIALIZED(ptr, count)                      \
  90   safe_alloc_alloc_n (&(ptr), sizeof (*(ptr)), (count), 0)
  91
  92 /**
  93  * REALLOC_N:
  94  * @ptr: pointer to hold address of allocated memory
  95  * @count: number of elements to allocate
  96  *
  97  * Re-allocate an array of 'count' elements, each sizeof(*ptr)
  98  * bytes long and store the address of allocated memory in
  99  * 'ptr'. Fill the newly allocated memory with zeros
 100  *
 101  * Return -1 on failure to reallocate, zero on success
 102  */
 103 # define REALLOC_N(ptr, count)                                  \
 104   safe_alloc_realloc_n (&(ptr), sizeof (*(ptr)), (count))
 105
 106 /**
 107  * FREE:
 108  * @ptr: pointer holding address to be freed
 109  *
 110  * Free the memory stored in 'ptr' and update to point
 111  * to NULL.
 112  */
 113 # define FREE(ptr)                              \
 114   do                                            \
 115     {                                           \
 116       free (ptr);                               \
 117       (ptr) = NULL;                             \
 118     }                                           \
 119   while (0)
 120
 121 #endif /* SAFE_ALLOC_H_ */