gmem.h revision 103fe49b8e410b5fee4144722f43f5bae4936fd1 
1/* GLIB - Library of useful routines for C programming
2 * Copyright (C) 1995-1997  Peter Mattis, Spencer Kimball and Josh MacDonald
3 *
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.
8 *
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.
13 *
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.
18 */
19
20/*
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/.
25 */
26
27#ifndef __G_MEM_H__
28#define __G_MEM_H__
29
30#include <glib/gtypes.h>
31
32G_BEGIN_DECLS
33
34typedef struct _GAllocator GAllocator;
35typedef struct _GMemChunk  GMemChunk;
36typedef struct _GMemVTable GMemVTable;
37
38
39#if GLIB_SIZEOF_VOID_P > GLIB_SIZEOF_LONG
40#  define G_MEM_ALIGN	GLIB_SIZEOF_VOID_P
41#else	/* GLIB_SIZEOF_VOID_P <= GLIB_SIZEOF_LONG */
42#  define G_MEM_ALIGN	GLIB_SIZEOF_LONG
43#endif	/* GLIB_SIZEOF_VOID_P <= GLIB_SIZEOF_LONG */
44
45
46/* Memory allocation functions
47 */
48gpointer g_malloc         (gulong	 n_bytes) G_GNUC_MALLOC;
49gpointer g_malloc0        (gulong	 n_bytes) G_GNUC_MALLOC;
50gpointer g_realloc        (gpointer	 mem,
51			   gulong	 n_bytes);
52void	 g_free	          (gpointer	 mem);
53gpointer g_try_malloc     (gulong	 n_bytes) G_GNUC_MALLOC;
54gpointer g_try_realloc    (gpointer	 mem,
55			   gulong	 n_bytes);
56
57
58/* Convenience memory allocators
59 */
60#define g_new(struct_type, n_structs)		\
61    ((struct_type *) g_malloc (((gsize) sizeof (struct_type)) * ((gsize) (n_structs))))
62#define g_new0(struct_type, n_structs)		\
63    ((struct_type *) g_malloc0 (((gsize) sizeof (struct_type)) * ((gsize) (n_structs))))
64#define g_renew(struct_type, mem, n_structs)	\
65    ((struct_type *) g_realloc ((mem), ((gsize) sizeof (struct_type)) * ((gsize) (n_structs))))
66
67#define g_try_new(struct_type, n_structs)		\
68    ((struct_type *) g_try_malloc (((gsize) sizeof (struct_type)) * ((gsize) (n_structs))))
69#define g_try_new0(struct_type, n_structs)		\
70    ((struct_type *) g_try_malloc0 (((gsize) sizeof (struct_type)) * ((gsize) (n_structs))))
71#define g_try_renew(struct_type, mem, n_structs)	\
72    ((struct_type *) g_try_realloc ((mem), ((gsize) sizeof (struct_type)) * ((gsize) (n_structs))))
73
74
75/* Memory allocation virtualization for debugging purposes
76 * g_mem_set_vtable() has to be the very first GLib function called
77 * if being used
78 */
79struct _GMemVTable
80{
81  gpointer (*malloc)      (gsize    n_bytes);
82  gpointer (*realloc)     (gpointer mem,
83			   gsize    n_bytes);
84  void     (*free)        (gpointer mem);
85  /* optional; set to NULL if not used ! */
86  gpointer (*calloc)      (gsize    n_blocks,
87			   gsize    n_block_bytes);
88  gpointer (*try_malloc)  (gsize    n_bytes);
89  gpointer (*try_realloc) (gpointer mem,
90			   gsize    n_bytes);
91};
92void	 g_mem_set_vtable (GMemVTable	*vtable);
93gboolean g_mem_is_system_malloc (void);
94
95/* Memory profiler and checker, has to be enabled via g_mem_set_vtable()
96 */
97GLIB_VAR GMemVTable	*glib_mem_profiler_table;
98void	g_mem_profile	(void);
99
100
101/* Memchunk convenience functions
102 */
103#define g_mem_chunk_create(type, pre_alloc, alloc_type)	( \
104  g_mem_chunk_new (#type " mem chunks (" #pre_alloc ")", \
105		   sizeof (type), \
106		   sizeof (type) * (pre_alloc), \
107		   (alloc_type)) \
108)
109#define g_chunk_new(type, chunk)	( \
110  (type *) g_mem_chunk_alloc (chunk) \
111)
112#define g_chunk_new0(type, chunk)	( \
113  (type *) g_mem_chunk_alloc0 (chunk) \
114)
115#define g_chunk_free(mem, mem_chunk)	G_STMT_START { \
116  g_mem_chunk_free ((mem_chunk), (mem)); \
117} G_STMT_END
118
119
120/* "g_mem_chunk_new" creates a new memory chunk.
121 * Memory chunks are used to allocate pieces of memory which are
122 *  always the same size. Lists are a good example of such a data type.
123 * The memory chunk allocates and frees blocks of memory as needed.
124 *  Just be sure to call "g_mem_chunk_free" and not "g_free" on data
125 *  allocated in a mem chunk. ("g_free" will most likely cause a seg
126 *  fault...somewhere).
127 *
128 * Oh yeah, GMemChunk is an opaque data type. (You don't really
129 *  want to know what's going on inside do you?)
130 */
131
132/* ALLOC_ONLY MemChunks can only allocate memory. The free operation
133 *  is interpreted as a no op. ALLOC_ONLY MemChunks save 4 bytes per
134 *  atom. (They are also useful for lists which use MemChunk to allocate
135 *  memory but are also part of the MemChunk implementation).
136 * ALLOC_AND_FREE MemChunks can allocate and free memory.
137 */
138
139#define G_ALLOC_ONLY	  1
140#define G_ALLOC_AND_FREE  2
141
142GMemChunk* g_mem_chunk_new     (const gchar *name,
143				gint         atom_size,
144				gulong       area_size,
145				gint         type);
146void       g_mem_chunk_destroy (GMemChunk   *mem_chunk);
147gpointer   g_mem_chunk_alloc   (GMemChunk   *mem_chunk);
148gpointer   g_mem_chunk_alloc0  (GMemChunk   *mem_chunk);
149void       g_mem_chunk_free    (GMemChunk   *mem_chunk,
150				gpointer     mem);
151void       g_mem_chunk_clean   (GMemChunk   *mem_chunk);
152void       g_mem_chunk_reset   (GMemChunk   *mem_chunk);
153void       g_mem_chunk_print   (GMemChunk   *mem_chunk);
154void       g_mem_chunk_info    (void);
155
156/* Ah yes...we have a "g_blow_chunks" function.
157 * "g_blow_chunks" simply compresses all the chunks. This operation
158 *  consists of freeing every memory area that should be freed (but
159 *  which we haven't gotten around to doing yet). And, no,
160 *  "g_blow_chunks" doesn't follow the naming scheme, but it is a
161 *  much better name than "g_mem_chunk_clean_all" or something
162 *  similar.
163 */
164void	   g_blow_chunks (void);
165
166
167/* Generic allocators
168 */
169GAllocator* g_allocator_new   (const gchar  *name,
170			       guint         n_preallocs);
171void        g_allocator_free  (GAllocator   *allocator);
172
173/* internal */
174#define	G_ALLOCATOR_LIST	(1)
175#define	G_ALLOCATOR_SLIST	(2)
176#define	G_ALLOCATOR_NODE	(3)
177
178
179G_END_DECLS
180
181#endif /* __G_MEM_H__ */
182