/* 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__ */