lib/safe-alloc.h

   1 /* safe-alloc.h: safer memory allocation
   2
   3    Copyright (C) 2009-2020 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 /* Don't call these directly - use the macros below */
  35 int
  36 safe_alloc_alloc_n (void *ptrptr, size_t size, size_t count, int zeroed)
  37   _GL_ATTRIBUTE_NODISCARD;
  38
  39 int
  40 safe_alloc_realloc_n (void *ptrptr, size_t size, size_t count)
  41   _GL_ATTRIBUTE_NODISCARD;
  42
  43 /**
  44  * ALLOC:
  45  * @ptr: pointer to hold address of allocated memory
  46  *
  47  * Allocate sizeof(*ptr) bytes of memory and store
  48  * the address of allocated memory in 'ptr'. Fill the
  49  * newly allocated memory with zeros.
  50  *
  51  * Return -1 on failure to allocate, zero on success
  52  */
  53 # define ALLOC(ptr)                                     \
  54   safe_alloc_alloc_n (&(ptr), sizeof (*(ptr)), 1, 1)
  55
  56 /**
  57  * ALLOC_N:
  58  * @ptr: pointer to hold address of allocated memory
  59  * @count: number of elements to allocate
  60  *
  61  * Allocate an array of 'count' elements, each sizeof(*ptr)
  62  * bytes long and store the address of allocated memory in
  63  * 'ptr'. Fill the newly allocated memory with zeros.
  64  *
  65  * Return -1 on failure, 0 on success
  66  */
  67 # define ALLOC_N(ptr, count)                                    \
  68   safe_alloc_alloc_n (&(ptr), sizeof (*(ptr)), (count), 1)
  69
  70 /**
  71  * ALLOC_N_UNINITIALIZED:
  72  * @ptr: pointer to hold address of allocated memory
  73  * @count: number of elements to allocate
  74  *
  75  * Allocate an array of 'count' elements, each sizeof(*ptr)
  76  * bytes long and store the address of allocated memory in
  77  * 'ptr'. Do not initialize the new memory at all.
  78  *
  79  * Return -1 on failure to allocate, zero on success
  80  */
  81 # define ALLOC_N_UNINITIALIZED(ptr, count)                      \
  82   safe_alloc_alloc_n (&(ptr), sizeof (*(ptr)), (count), 0)
  83
  84 /**
  85  * REALLOC_N:
  86  * @ptr: pointer to hold address of allocated memory
  87  * @count: number of elements to allocate
  88  *
  89  * Re-allocate an array of 'count' elements, each sizeof(*ptr)
  90  * bytes long and store the address of allocated memory in
  91  * 'ptr'. Fill the newly allocated memory with zeros
  92  *
  93  * Return -1 on failure to reallocate, zero on success
  94  */
  95 # define REALLOC_N(ptr, count)                                  \
  96   safe_alloc_realloc_n (&(ptr), sizeof (*(ptr)), (count))
  97
  98 /**
  99  * FREE:
 100  * @ptr: pointer holding address to be freed
 101  *
 102  * Free the memory stored in 'ptr' and update to point
 103  * to NULL.
 104  */
 105 # define FREE(ptr)                              \
 106   do                                            \
 107     {                                           \
 108       free (ptr);                               \
 109       (ptr) = NULL;                             \
 110     }                                           \
 111   while (0)
 112
 113 #endif /* SAFE_ALLOC_H_ */