1 /* GLIB - Library of useful routines for C programming
2 * Copyright (C) 1995-1997 Peter Mattis, Spencer Kimball and Josh MacDonald
4 * This library is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Lesser General Public
6 * License as published by the Free Software Foundation; either
7 * version 2 of the License, or (at your option) any later version.
9 * This library is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * Lesser General Public License for more details.
14 * You should have received a copy of the GNU Lesser General Public
15 * License along with this library; if not, write to the
16 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
17 * Boston, MA 02111-1307, USA.
21 * Modified by the GLib Team and others 1997-2000. See the AUTHORS
22 * file for a list of people on the GLib Team. See the ChangeLog
23 * files for a list of changes. These files are distributed with
24 * GLib at ftp://ftp.gtk.org/pub/gtk/.
27 #if !defined (__GLIB_H_INSIDE__) && !defined (GLIB_COMPILATION)
28 #error "Only <glib.h> can be included directly."
34 #include <glib/gtypes.h>
40 * @malloc: function to use for allocating memory.
41 * @realloc: function to use for reallocating memory.
42 * @free: function to use to free memory.
43 * @calloc: function to use for allocating zero-filled memory.
44 * @try_malloc: function to use for allocating memory without a default error handler.
45 * @try_realloc: function to use for reallocating memory without a default error handler.
47 * A set of functions used to perform memory allocation. The same #GMemVTable must
48 * be used for all allocations in the same program; a call to g_mem_set_vtable(),
49 * if it exists, should be prior to any use of GLib.
51 typedef struct _GMemVTable GMemVTable;
54 #if GLIB_SIZEOF_VOID_P > GLIB_SIZEOF_LONG
58 * Indicates the number of bytes to which memory will be aligned on the
61 # define G_MEM_ALIGN GLIB_SIZEOF_VOID_P
62 #else /* GLIB_SIZEOF_VOID_P <= GLIB_SIZEOF_LONG */
63 # define G_MEM_ALIGN GLIB_SIZEOF_LONG
64 #endif /* GLIB_SIZEOF_VOID_P <= GLIB_SIZEOF_LONG */
67 /* Memory allocation functions
70 void g_free (gpointer mem);
72 GLIB_AVAILABLE_IN_2_34
73 void g_clear_pointer (gpointer *pp,
74 GDestroyNotify destroy);
76 gpointer g_malloc (gsize n_bytes) G_GNUC_MALLOC G_GNUC_ALLOC_SIZE(1);
77 gpointer g_malloc0 (gsize n_bytes) G_GNUC_MALLOC G_GNUC_ALLOC_SIZE(1);
78 gpointer g_realloc (gpointer mem,
79 gsize n_bytes) G_GNUC_WARN_UNUSED_RESULT;
80 gpointer g_try_malloc (gsize n_bytes) G_GNUC_MALLOC G_GNUC_ALLOC_SIZE(1);
81 gpointer g_try_malloc0 (gsize n_bytes) G_GNUC_MALLOC G_GNUC_ALLOC_SIZE(1);
82 gpointer g_try_realloc (gpointer mem,
83 gsize n_bytes) G_GNUC_WARN_UNUSED_RESULT;
85 gpointer g_malloc_n (gsize n_blocks,
86 gsize n_block_bytes) G_GNUC_MALLOC G_GNUC_ALLOC_SIZE2(1,2);
87 gpointer g_malloc0_n (gsize n_blocks,
88 gsize n_block_bytes) G_GNUC_MALLOC G_GNUC_ALLOC_SIZE2(1,2);
89 gpointer g_realloc_n (gpointer mem,
91 gsize n_block_bytes) G_GNUC_WARN_UNUSED_RESULT;
92 gpointer g_try_malloc_n (gsize n_blocks,
93 gsize n_block_bytes) G_GNUC_MALLOC G_GNUC_ALLOC_SIZE2(1,2);
94 gpointer g_try_malloc0_n (gsize n_blocks,
95 gsize n_block_bytes) G_GNUC_MALLOC G_GNUC_ALLOC_SIZE2(1,2);
96 gpointer g_try_realloc_n (gpointer mem,
98 gsize n_block_bytes) G_GNUC_WARN_UNUSED_RESULT;
100 #define g_clear_pointer(pp, destroy) \
102 G_STATIC_ASSERT (sizeof *(pp) == sizeof (gpointer)); \
103 /* Only one access, please */ \
104 gpointer *_pp = (gpointer *) (pp); \
107 (void) (0 ? (gpointer) *(pp) : 0); \
109 _p = g_atomic_pointer_get (_pp); \
110 while G_UNLIKELY (!g_atomic_pointer_compare_and_exchange (_pp, _p, NULL)); \
113 ((GDestroyNotify) (destroy)) (_p); \
116 /* Optimise: avoid the call to the (slower) _n function if we can
117 * determine at compile-time that no overflow happens.
119 #if defined (__GNUC__) && (__GNUC__ >= 2) && defined (__OPTIMIZE__)
120 # define _G_NEW(struct_type, n_structs, func) \
121 (struct_type *) (G_GNUC_EXTENSION ({ \
122 gsize __n = (gsize) (n_structs); \
123 gsize __s = sizeof (struct_type); \
126 __p = g_##func (__n); \
127 else if (__builtin_constant_p (__n) && \
128 (__s == 0 || __n <= G_MAXSIZE / __s)) \
129 __p = g_##func (__n * __s); \
131 __p = g_##func##_n (__n, __s); \
134 # define _G_RENEW(struct_type, mem, n_structs, func) \
135 (struct_type *) (G_GNUC_EXTENSION ({ \
136 gsize __n = (gsize) (n_structs); \
137 gsize __s = sizeof (struct_type); \
138 gpointer __p = (gpointer) (mem); \
140 __p = g_##func (__p, __n); \
141 else if (__builtin_constant_p (__n) && \
142 (__s == 0 || __n <= G_MAXSIZE / __s)) \
143 __p = g_##func (__p, __n * __s); \
145 __p = g_##func##_n (__p, __n, __s); \
151 /* Unoptimised version: always call the _n() function. */
153 #define _G_NEW(struct_type, n_structs, func) \
154 ((struct_type *) g_##func##_n ((n_structs), sizeof (struct_type)))
155 #define _G_RENEW(struct_type, mem, n_structs, func) \
156 ((struct_type *) g_##func##_n (mem, (n_structs), sizeof (struct_type)))
162 * @struct_type: the type of the elements to allocate
163 * @n_structs: the number of elements to allocate
165 * Allocates @n_structs elements of type @struct_type.
166 * The returned pointer is cast to a pointer to the given type.
167 * If @n_structs is 0 it returns %NULL.
168 * Care is taken to avoid overflow when calculating the size of the allocated block.
170 * Since the returned pointer is already casted to the right type,
171 * it is normally unnecessary to cast it explicitly, and doing
172 * so might hide memory allocation errors.
174 * Returns: a pointer to the allocated memory, cast to a pointer to @struct_type
176 #define g_new(struct_type, n_structs) _G_NEW (struct_type, n_structs, malloc)
179 * @struct_type: the type of the elements to allocate.
180 * @n_structs: the number of elements to allocate.
182 * Allocates @n_structs elements of type @struct_type, initialized to 0's.
183 * The returned pointer is cast to a pointer to the given type.
184 * If @n_structs is 0 it returns %NULL.
185 * Care is taken to avoid overflow when calculating the size of the allocated block.
187 * Since the returned pointer is already casted to the right type,
188 * it is normally unnecessary to cast it explicitly, and doing
189 * so might hide memory allocation errors.
191 * Returns: a pointer to the allocated memory, cast to a pointer to @struct_type.
193 #define g_new0(struct_type, n_structs) _G_NEW (struct_type, n_structs, malloc0)
196 * @struct_type: the type of the elements to allocate
197 * @mem: the currently allocated memory
198 * @n_structs: the number of elements to allocate
200 * Reallocates the memory pointed to by @mem, so that it now has space for
201 * @n_structs elements of type @struct_type. It returns the new address of
202 * the memory, which may have been moved.
203 * Care is taken to avoid overflow when calculating the size of the allocated block.
205 * Returns: a pointer to the new allocated memory, cast to a pointer to @struct_type
207 #define g_renew(struct_type, mem, n_structs) _G_RENEW (struct_type, mem, n_structs, realloc)
210 * @struct_type: the type of the elements to allocate
211 * @n_structs: the number of elements to allocate
213 * Attempts to allocate @n_structs elements of type @struct_type, and returns
214 * %NULL on failure. Contrast with g_new(), which aborts the program on failure.
215 * The returned pointer is cast to a pointer to the given type.
216 * The function returns %NULL when @n_structs is 0 of if an overflow occurs.
219 * Returns: a pointer to the allocated memory, cast to a pointer to @struct_type
221 #define g_try_new(struct_type, n_structs) _G_NEW (struct_type, n_structs, try_malloc)
224 * @struct_type: the type of the elements to allocate
225 * @n_structs: the number of elements to allocate
227 * Attempts to allocate @n_structs elements of type @struct_type, initialized
228 * to 0's, and returns %NULL on failure. Contrast with g_new0(), which aborts
229 * the program on failure.
230 * The returned pointer is cast to a pointer to the given type.
231 * The function returns %NULL when @n_structs is 0 of if an overflow occurs.
234 * Returns: a pointer to the allocated memory, cast to a pointer to @struct_type
236 #define g_try_new0(struct_type, n_structs) _G_NEW (struct_type, n_structs, try_malloc0)
239 * @struct_type: the type of the elements to allocate
240 * @mem: the currently allocated memory
241 * @n_structs: the number of elements to allocate
243 * Attempts to reallocate the memory pointed to by @mem, so that it now has
244 * space for @n_structs elements of type @struct_type, and returns %NULL on
245 * failure. Contrast with g_renew(), which aborts the program on failure.
246 * It returns the new address of the memory, which may have been moved.
247 * The function returns %NULL if an overflow occurs.
250 * Returns: a pointer to the new allocated memory, cast to a pointer to @struct_type
252 #define g_try_renew(struct_type, mem, n_structs) _G_RENEW (struct_type, mem, n_structs, try_realloc)
255 /* Memory allocation virtualization for debugging purposes
256 * g_mem_set_vtable() has to be the very first GLib function called
260 gpointer (*malloc) (gsize n_bytes);
261 gpointer (*realloc) (gpointer mem,
263 void (*free) (gpointer mem);
264 /* optional; set to NULL if not used ! */
265 gpointer (*calloc) (gsize n_blocks,
266 gsize n_block_bytes);
267 gpointer (*try_malloc) (gsize n_bytes);
268 gpointer (*try_realloc) (gpointer mem,
271 void g_mem_set_vtable (GMemVTable *vtable);
272 gboolean g_mem_is_system_malloc (void);
274 GLIB_VAR gboolean g_mem_gc_friendly;
276 /* Memory profiler and checker, has to be enabled via g_mem_set_vtable()
278 GLIB_VAR GMemVTable *glib_mem_profiler_table;
279 void g_mem_profile (void);
283 #endif /* __G_MEM_H__ */