/* GLIB - Library of useful routines for C programming

 * Copyright (C) 1995-1997  Peter Mattis, Spencer Kimball and Josh MacDonald

 *

 * This library is free software; you can redistribute it and/or

 * modify it under the terms of the GNU Lesser General Public

 * License as published by the Free Software Foundation; either

 * version 2.1 of the License, or (at your option) any later version.

 *

 * This library 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

 * Lesser General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public

 * License along with this library; if not, see <http://www.gnu.org/licenses/>.

 */

/*

 * Modified by the GLib Team and others 1997-2000.  See the AUTHORS

 * file for a list of people on the GLib Team.  See the ChangeLog

 * files for a list of changes.  These files are distributed with

 * GLib at ftp://ftp.gtk.org/pub/gtk/.

 */

#ifndef __G_MEM_H__

#define __G_MEM_H__

#if !defined (__GLIB_H_INSIDE__) && !defined (GLIB_COMPILATION)

#error "Only <glib.h> can be included directly."

#endif

#include <glib/gutils.h>

G_BEGIN_DECLS

/**

 * GMemVTable:

 * @malloc: function to use for allocating memory.

 * @realloc: function to use for reallocating memory.

 * @free: function to use to free memory.

 * @calloc: function to use for allocating zero-filled memory.

 * @try_malloc: function to use for allocating memory without a default error handler.

 * @try_realloc: function to use for reallocating memory without a default error handler.

 * 

 * A set of functions used to perform memory allocation. The same #GMemVTable must

 * be used for all allocations in the same program; a call to g_mem_set_vtable(),

 * if it exists, should be prior to any use of GLib.

 *

 * This functions related to this has been deprecated in 2.46, and no longer work.

 */

typedef struct _GMemVTable GMemVTable;

#if GLIB_SIZEOF_VOID_P > GLIB_SIZEOF_LONG

/**

 * G_MEM_ALIGN:

 *

 * Indicates the number of bytes to which memory will be aligned on the

 * current platform.

 */

#  define G_MEM_ALIGN	GLIB_SIZEOF_VOID_P

#else	/* GLIB_SIZEOF_VOID_P <= GLIB_SIZEOF_LONG */

#  define G_MEM_ALIGN	GLIB_SIZEOF_LONG

#endif	/* GLIB_SIZEOF_VOID_P <= GLIB_SIZEOF_LONG */

/* Memory allocation functions

 */

GLIB_AVAILABLE_IN_ALL

void	 g_free	          (gpointer	 mem);

GLIB_AVAILABLE_IN_2_34

void     g_clear_pointer  (gpointer      *pp,

                           GDestroyNotify destroy);

GLIB_AVAILABLE_IN_ALL

gpointer g_malloc         (gsize	 n_bytes) G_GNUC_MALLOC G_GNUC_ALLOC_SIZE(1);

GLIB_AVAILABLE_IN_ALL

gpointer g_malloc0        (gsize	 n_bytes) G_GNUC_MALLOC G_GNUC_ALLOC_SIZE(1);

GLIB_AVAILABLE_IN_ALL

gpointer g_realloc        (gpointer	 mem,

			   gsize	 n_bytes) G_GNUC_WARN_UNUSED_RESULT;

GLIB_AVAILABLE_IN_ALL

gpointer g_try_malloc     (gsize	 n_bytes) G_GNUC_MALLOC G_GNUC_ALLOC_SIZE(1);

GLIB_AVAILABLE_IN_ALL

gpointer g_try_malloc0    (gsize	 n_bytes) G_GNUC_MALLOC G_GNUC_ALLOC_SIZE(1);

GLIB_AVAILABLE_IN_ALL

gpointer g_try_realloc    (gpointer	 mem,

			   gsize	 n_bytes) G_GNUC_WARN_UNUSED_RESULT;

GLIB_AVAILABLE_IN_ALL

gpointer g_malloc_n       (gsize	 n_blocks,

			   gsize	 n_block_bytes) G_GNUC_MALLOC G_GNUC_ALLOC_SIZE2(1,2);

GLIB_AVAILABLE_IN_ALL

gpointer g_malloc0_n      (gsize	 n_blocks,

			   gsize	 n_block_bytes) G_GNUC_MALLOC G_GNUC_ALLOC_SIZE2(1,2);

GLIB_AVAILABLE_IN_ALL

gpointer g_realloc_n      (gpointer	 mem,

			   gsize	 n_blocks,

			   gsize	 n_block_bytes) G_GNUC_WARN_UNUSED_RESULT;

GLIB_AVAILABLE_IN_ALL

gpointer g_try_malloc_n   (gsize	 n_blocks,

			   gsize	 n_block_bytes) G_GNUC_MALLOC G_GNUC_ALLOC_SIZE2(1,2);

GLIB_AVAILABLE_IN_ALL

gpointer g_try_malloc0_n  (gsize	 n_blocks,

			   gsize	 n_block_bytes) G_GNUC_MALLOC G_GNUC_ALLOC_SIZE2(1,2);

GLIB_AVAILABLE_IN_ALL

gpointer g_try_realloc_n  (gpointer	 mem,

			   gsize	 n_blocks,

			   gsize	 n_block_bytes) G_GNUC_WARN_UNUSED_RESULT;

#define g_clear_pointer(pp, destroy) \

  G_STMT_START {                                                               \

    G_STATIC_ASSERT (sizeof *(pp) == sizeof (gpointer));                       \

    /* Only one access, please; work around type aliasing */                   \

    union { char *in; gpointer *out; } _pp;                                    \

    gpointer _p;                                                               \

    /* This assignment is needed to avoid a gcc warning */                     \

    GDestroyNotify _destroy = (GDestroyNotify) (destroy);                      \

                                                                               \

    _pp.in = (char *) (pp);                                                    \

    _p = *_pp.out;                                                             \

    if (_p) 								       \

      { 								       \

        *_pp.out = NULL;                                                       \

        _destroy (_p);                                                         \

      }                                                                        \

  } G_STMT_END

/**

 * g_steal_pointer:

 * @pp: (not nullable): a pointer to a pointer

 *

 * Sets @pp to %NULL, returning the value that was there before.

 *

 * Conceptually, this transfers the ownership of the pointer from the

 * referenced variable to the "caller" of the macro (ie: "steals" the

 * reference).

 *

 * The return value will be properly typed, according to the type of

 * @pp.

 *

 * This can be very useful when combined with g_autoptr() to prevent the

 * return value of a function from being automatically freed.  Consider

 * the following example (which only works on GCC and clang):

 *

 * |[

 * GObject *

 * create_object (void)

 * {

 *   g_autoptr(GObject) obj = g_object_new (G_TYPE_OBJECT, NULL);

 *

 *   if (early_error_case)

 *     return NULL;

 *

 *   return g_steal_pointer (&obj);

 * }

 * ]|

 *

 * It can also be used in similar ways for 'out' parameters and is

 * particularly useful for dealing with optional out parameters:

 *

 * |[

 * gboolean

 * get_object (GObject **obj_out)

 * {

 *   g_autoptr(GObject) obj = g_object_new (G_TYPE_OBJECT, NULL);

 *

 *   if (early_error_case)

 *     return FALSE;

 *

 *   if (obj_out)

 *     *obj_out = g_steal_pointer (&obj);

 *

 *   return TRUE;

 * }

 * ]|

 *

 * In the above example, the object will be automatically freed in the

 * early error case and also in the case that %NULL was given for

 * @obj_out.

 *

 * Since: 2.44

 */

static inline gpointer

g_steal_pointer (gpointer pp)

{

  gpointer *ptr = (gpointer *) pp;

  gpointer ref;

  ref = *ptr;

  *ptr = NULL;

  return ref;

}

/* type safety */

#define g_steal_pointer(pp) \

  (0 ? (*(pp)) : (g_steal_pointer) (pp))

/* Optimise: avoid the call to the (slower) _n function if we can

 * determine at compile-time that no overflow happens.

 */

#if defined (__GNUC__) && (__GNUC__ >= 2) && defined (__OPTIMIZE__)

#  define _G_NEW(struct_type, n_structs, func) \

	(struct_type *) (G_GNUC_EXTENSION ({			\

	  gsize __n = (gsize) (n_structs);			\

	  gsize __s = sizeof (struct_type);			\

	  gpointer __p;						\

	  if (__s == 1)						\

	    __p = g_##func (__n);				\

	  else if (__builtin_constant_p (__n) &&		\

	           (__s == 0 || __n <= G_MAXSIZE / __s))	\

	    __p = g_##func (__n * __s);				\

	  else							\

	    __p = g_##func##_n (__n, __s);			\

	  __p;							\

	}))

#  define _G_RENEW(struct_type, mem, n_structs, func) \

	(struct_type *) (G_GNUC_EXTENSION ({			\

	  gsize __n = (gsize) (n_structs);			\

	  gsize __s = sizeof (struct_type);			\

	  gpointer __p = (gpointer) (mem);			\

	  if (__s == 1)						\

	    __p = g_##func (__p, __n);				\

	  else if (__builtin_constant_p (__n) &&		\

	           (__s == 0 || __n <= G_MAXSIZE / __s))	\

	    __p = g_##func (__p, __n * __s);			\

	  else							\

	    __p = g_##func##_n (__p, __n, __s);			\

	  __p;							\

	}))

#else

/* Unoptimised version: always call the _n() function. */

#define _G_NEW(struct_type, n_structs, func) \

        ((struct_type *) g_##func##_n ((n_structs), sizeof (struct_type)))

#define _G_RENEW(struct_type, mem, n_structs, func) \

        ((struct_type *) g_##func##_n (mem, (n_structs), sizeof (struct_type)))

#endif

/**

 * g_new:

 * @struct_type: the type of the elements to allocate

 * @n_structs: the number of elements to allocate

 * 

 * Allocates @n_structs elements of type @struct_type.

 * The returned pointer is cast to a pointer to the given type.

 * If @n_structs is 0 it returns %NULL.

 * Care is taken to avoid overflow when calculating the size of the allocated block.

 * 

 * Since the returned pointer is already casted to the right type,

 * it is normally unnecessary to cast it explicitly, and doing

 * so might hide memory allocation errors.

 * 

 * Returns: a pointer to the allocated memory, cast to a pointer to @struct_type

 */

#define g_new(struct_type, n_structs)			_G_NEW (struct_type, n_structs, malloc)

/**

 * g_new0:

 * @struct_type: the type of the elements to allocate.

 * @n_structs: the number of elements to allocate.

 * 

 * Allocates @n_structs elements of type @struct_type, initialized to 0's.

 * The returned pointer is cast to a pointer to the given type.

 * If @n_structs is 0 it returns %NULL.

 * Care is taken to avoid overflow when calculating the size of the allocated block.

 * 

 * Since the returned pointer is already casted to the right type,

 * it is normally unnecessary to cast it explicitly, and doing

 * so might hide memory allocation errors.

 * 

 * Returns: a pointer to the allocated memory, cast to a pointer to @struct_type.

 */

#define g_new0(struct_type, n_structs)			_G_NEW (struct_type, n_structs, malloc0)

/**

 * g_renew:

 * @struct_type: the type of the elements to allocate

 * @mem: the currently allocated memory

 * @n_structs: the number of elements to allocate

 * 

 * Reallocates the memory pointed to by @mem, so that it now has space for

 * @n_structs elements of type @struct_type. It returns the new address of

 * the memory, which may have been moved.

 * Care is taken to avoid overflow when calculating the size of the allocated block.

 * 

 * Returns: a pointer to the new allocated memory, cast to a pointer to @struct_type

 */

#define g_renew(struct_type, mem, n_structs)		_G_RENEW (struct_type, mem, n_structs, realloc)

/**

 * g_try_new:

 * @struct_type: the type of the elements to allocate

 * @n_structs: the number of elements to allocate

 * 

 * Attempts to allocate @n_structs elements of type @struct_type, and returns

 * %NULL on failure. Contrast with g_new(), which aborts the program on failure.

 * The returned pointer is cast to a pointer to the given type.

 * The function returns %NULL when @n_structs is 0 of if an overflow occurs.

 * 

 * Since: 2.8

 * Returns: a pointer to the allocated memory, cast to a pointer to @struct_type

 */

#define g_try_new(struct_type, n_structs)		_G_NEW (struct_type, n_structs, try_malloc)

/**

 * g_try_new0:

 * @struct_type: the type of the elements to allocate

 * @n_structs: the number of elements to allocate

 * 

 * Attempts to allocate @n_structs elements of type @struct_type, initialized

 * to 0's, and returns %NULL on failure. Contrast with g_new0(), which aborts

 * the program on failure.

 * The returned pointer is cast to a pointer to the given type.

 * The function returns %NULL when @n_structs is 0 or if an overflow occurs.

 * 

 * Since: 2.8

 * Returns: a pointer to the allocated memory, cast to a pointer to @struct_type

 */

#define g_try_new0(struct_type, n_structs)		_G_NEW (struct_type, n_structs, try_malloc0)

/**

 * g_try_renew:

 * @struct_type: the type of the elements to allocate

 * @mem: the currently allocated memory

 * @n_structs: the number of elements to allocate

 * 

 * Attempts to reallocate the memory pointed to by @mem, so that it now has

 * space for @n_structs elements of type @struct_type, and returns %NULL on

 * failure. Contrast with g_renew(), which aborts the program on failure.

 * It returns the new address of the memory, which may have been moved.

 * The function returns %NULL if an overflow occurs.

 * 

 * Since: 2.8

 * Returns: a pointer to the new allocated memory, cast to a pointer to @struct_type

 */

#define g_try_renew(struct_type, mem, n_structs)	_G_RENEW (struct_type, mem, n_structs, try_realloc)

/* Memory allocation virtualization for debugging purposes

 * g_mem_set_vtable() has to be the very first GLib function called

 * if being used

 */

struct _GMemVTable {

  gpointer (*malloc)      (gsize    n_bytes);

  gpointer (*realloc)     (gpointer mem,

			   gsize    n_bytes);

  void     (*free)        (gpointer mem);

  /* optional; set to NULL if not used ! */

  gpointer (*calloc)      (gsize    n_blocks,

			   gsize    n_block_bytes);

  gpointer (*try_malloc)  (gsize    n_bytes);

  gpointer (*try_realloc) (gpointer mem,

			   gsize    n_bytes);

};

GLIB_DEPRECATED_IN_2_46

void	 g_mem_set_vtable (GMemVTable	*vtable);

GLIB_DEPRECATED_IN_2_46

gboolean g_mem_is_system_malloc (void);

GLIB_VAR gboolean g_mem_gc_friendly;

/* Memory profiler and checker, has to be enabled via g_mem_set_vtable()

 */

GLIB_VAR GMemVTable	*glib_mem_profiler_table;

GLIB_DEPRECATED_IN_2_46

void	g_mem_profile	(void);

G_END_DECLS

#endif /* __G_MEM_H__ */