samba-mirror/source4/lib/util/util.h

/* 
   Unix SMB/CIFS implementation.
   Utility functions for Samba
   Copyright (C) Andrew Tridgell 1992-1999
   Copyright (C) John H Terpstra 1996-1999
   Copyright (C) Luke Kenneth Casson Leighton 1996-1999
   Copyright (C) Paul Ashton 1998 - 1999
    
   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 2 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, write to the Free Software
   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/

#ifndef _SAMBA_UTIL_H_
#define _SAMBA_UTIL_H_

#include "core.h"
#include "charset/charset.h"

/**
 * @file
 * @brief Helpful macros
 */

struct substitute_context;
struct smbsrv_tcon;

extern const char *logfile;
extern const char *panic_action;

#include "util/xfile.h"
#include "util/debug.h"
#include "util/mutex.h"
#include "util/byteorder.h"
#include "lib/util/util_proto.h"

/** 
 * zero a structure 
 */
#define ZERO_STRUCT(x) memset((char *)&(x), 0, sizeof(x))

/** 
 * zero a structure given a pointer to the structure 
 */
#define ZERO_STRUCTP(x) do { if ((x) != NULL) memset((char *)(x), 0, sizeof(*(x))); } while(0)

/** 
 * zero a structure given a pointer to the structure - no zero check 
 */
#define ZERO_STRUCTPN(x) memset((char *)(x), 0, sizeof(*(x)))

/** 
 * pointer difference macro 
 */
#define PTR_DIFF(p1,p2) ((ptrdiff_t)(((const char *)(p1)) - (const char *)(p2)))

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

/**
 * assert macros 
 */
#define SMB_ASSERT(b) do { if (!(b)) { \
	DEBUG(0,("PANIC: assert failed at %s(%d)\n", __FILE__, __LINE__)); \
	smb_panic("assert failed"); abort(); }} while (0)

#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(discard_const_p(void *, (x))); (x)=NULL;} } while(0)
#endif

/** 
 * 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)

/** 
 * 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)

#if defined(VALGRIND)
#define strlen(x) valgrind_strlen(x)
#endif

/**
  this is a warning hack. The idea is to use this everywhere that we
  get the "discarding const" warning from gcc. That doesn't actually
  fix the problem of course, but it means that when we do get to
  cleaning them up we can do it by searching the code for
  discard_const.

  It also means that other error types aren't as swamped by the noise
  of hundreds of const warnings, so we are more likely to notice when
  we get new errors.

  Please only add more uses of this macro when you find it
  _really_ hard to fix const warnings. Our aim is to eventually use
  this function in only a very few places.

  Also, please call this via the discard_const_p() macro interface, as that
  makes the return type safe.
*/
#define discard_const(ptr) ((void *)((intptr_t)(ptr)))

/** Type-safe version of discard_const */
#define discard_const_p(type, ptr) ((type *)discard_const(ptr))

#endif /* _SAMBA_UTIL_H_ */