glib/gmem.h

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