samba-mirror/lib/util/memory.h

/*
   Unix SMB/CIFS implementation.
   Samba utility functions
   Copyright (C) Andrew Tridgell 1992-1999
   Copyright (C) Jelmer Vernooij <jelmer@samba.org> 2008

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 3 of the License, or
   (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

#ifndef _SAMBA_MEMORY_H_
#define _SAMBA_MEMORY_H_

#ifndef SAFE_FREE /* Oh no this is also defined in tdb.h */
/**
 * Free memory if the pointer and zero the pointer.
 *
 * @note You are explicitly allowed to pass NULL pointers -- they will
 * always be ignored.
 **/
#define SAFE_FREE(x) do { if ((x) != NULL) {free(x); (x)=NULL;} } while(0)
#endif

/**
 * Zero string and free memory if the pointer and zero the pointer.
 *
 * @note You are explicitly allowed to pass NULL pointers -- they will
 * always be ignored.
 **/
#define BURN_FREE_STR(x) do { \
				if ((x) != NULL) { \
					size_t s = strlen(x); \
					memset_s((x), s, 0, s); \
					free(x); (x) = NULL; \
				} \
			} while(0)

/**
 * Zero and free memory if the pointer and zero the pointer.
 *
 * @note You are explicitly allowed to pass NULL pointers -- they will
 * always be ignored.
 **/
#define BURN_FREE(x, s) do { \
				if ((x) != NULL) { \
					memset_s((x), (s), 0, (s)); \
					free(x); (x) = NULL; \
				} \
			} while(0)

/**
 * Type-safe version of malloc. Allocated one copy of the
 * specified data type.
 */
#define malloc_p(type) (type *)malloc(sizeof(type))

/**
 * Allocate an array of elements of one data type. Does type-checking.
 */
#define malloc_array_p(type, count) (type *)realloc_array(NULL, sizeof(type), count, false)

/**
 * Resize an array of elements of one data type. Does type-checking.
 */
#define realloc_p(p, type, count) (type *)realloc_array(p, sizeof(type), count, false)

/**
 * Zero a structure.
 */
#ifndef ZERO_STRUCT
#define ZERO_STRUCT(x) memset_s((char *)&(x), sizeof(x), 0, sizeof(x))
#endif

/**
 * Zero a structure given a pointer to the structure.
 */
#ifndef ZERO_STRUCTP
#define ZERO_STRUCTP(x) do { \
	if ((x) != NULL) { \
		memset_s((char *)(x), sizeof(*(x)), 0, sizeof(*(x))); \
	} \
} while(0)
#endif

/**
 * Zero a structure given a pointer to the structure - no zero check.
 */
#ifndef ZERO_STRUCTPN
#define ZERO_STRUCTPN(x) memset_s((char *)(x), sizeof(*(x)), 0, sizeof(*(x)))
#endif

/**
 * Zero an array - note that sizeof(array) must work - ie. it must not be a
 * pointer.
 */
#ifndef ZERO_ARRAY
#define ZERO_ARRAY(x) memset_s((char *)(x), sizeof(x), 0, sizeof(x))
#endif

/**
 * Zero a given len of an array
 */
#define ZERO_ARRAY_LEN(x, l) memset_s((char *)(x), (l), 0, (l))

/**
 * Work out how many elements there are in a static array
 */
#ifndef ARRAY_SIZE
#define ARRAY_SIZE(a) (sizeof(a)/sizeof(a[0]))
#endif

/**
 * Pointer difference macro.
 */
#ifndef PTR_DIFF
#define PTR_DIFF(p1,p2) ((ptrdiff_t)(((const char *)(p1)) - (const char *)(p2)))
#endif

#endif /* _SAMBA_MEMORY_H_ */