1  /* GLIB sliced memory - fast threaded memory chunk allocator
       2   * Copyright (C) 2005 Tim Janik
       3   *
       4   * SPDX-License-Identifier: LGPL-2.1-or-later
       5   *
       6   * This library is free software; you can redistribute it and/or
       7   * modify it under the terms of the GNU Lesser General Public
       8   * License as published by the Free Software Foundation; either
       9   * version 2.1 of the License, or (at your option) any later version.
      10   *
      11   * This library is distributed in the hope that it will be useful,
      12   * but WITHOUT ANY WARRANTY; without even the implied warranty of
      13   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
      14   * Lesser General Public License for more details.
      15   *
      16   * You should have received a copy of the GNU Lesser General Public
      17   * License along with this library; if not, see <http://www.gnu.org/licenses/>.
      18   */
      19  
      20  #ifndef __G_SLICE_H__
      21  #define __G_SLICE_H__
      22  
      23  #if !defined (__GLIB_H_INSIDE__) && !defined (GLIB_COMPILATION)
      24  #error "Only <glib.h> can be included directly."
      25  #endif
      26  
      27  #include <glib/gtypes.h>
      28  #include <string.h>
      29  
      30  G_BEGIN_DECLS
      31  
      32  /* slices - fast allocation/release of small memory blocks
      33   */
      34  GLIB_AVAILABLE_IN_ALL
      35  gpointer g_slice_alloc          	(gsize	       block_size) G_GNUC_MALLOC G_GNUC_ALLOC_SIZE(1);
      36  GLIB_AVAILABLE_IN_ALL
      37  gpointer g_slice_alloc0         	(gsize         block_size) G_GNUC_MALLOC G_GNUC_ALLOC_SIZE(1);
      38  GLIB_AVAILABLE_IN_ALL
      39  gpointer g_slice_copy                   (gsize         block_size,
      40                                           gconstpointer mem_block) G_GNUC_ALLOC_SIZE(1);
      41  GLIB_AVAILABLE_IN_ALL
      42  void     g_slice_free1          	(gsize         block_size,
      43  					 gpointer      mem_block);
      44  GLIB_AVAILABLE_IN_ALL
      45  void     g_slice_free_chain_with_offset (gsize         block_size,
      46  					 gpointer      mem_chain,
      47  					 gsize         next_offset);
      48  #define  g_slice_new(type)      ((type*) g_slice_alloc (sizeof (type)))
      49  
      50  /* Allow the compiler to inline memset(). Since the size is a constant, this
      51   * can significantly improve performance. */
      52  #if defined (__GNUC__) && (__GNUC__ >= 2) && defined (__OPTIMIZE__)
      53  #  define g_slice_new0(type)                                    \
      54    (type *) (G_GNUC_EXTENSION ({                                 \
      55      gsize __s = sizeof (type);                                  \
      56      gpointer __p;                                               \
      57      __p = g_slice_alloc (__s);                                  \
      58      memset (__p, 0, __s);                                       \
      59      __p;                                                        \
      60    }))
      61  #else
      62  #  define g_slice_new0(type)    ((type*) g_slice_alloc0 (sizeof (type)))
      63  #endif
      64  
      65  /* MemoryBlockType *
      66   *       g_slice_dup                    (MemoryBlockType,
      67   *	                                 MemoryBlockType *mem_block);
      68   *       g_slice_free                   (MemoryBlockType,
      69   *	                                 MemoryBlockType *mem_block);
      70   *       g_slice_free_chain             (MemoryBlockType,
      71   *                                       MemoryBlockType *first_chain_block,
      72   *                                       memory_block_next_field);
      73   * pseudo prototypes for the macro
      74   * definitions following below.
      75   */
      76  
      77  /* we go through extra hoops to ensure type safety */
      78  #define g_slice_dup(type, mem)                                  \
      79    (1 ? (type*) g_slice_copy (sizeof (type), (mem))              \
      80       : ((void) ((type*) 0 == (mem)), (type*) 0))
      81  #define g_slice_free(type, mem)                                 \
      82  G_STMT_START {                                                  \
      83    if (1) g_slice_free1 (sizeof (type), (mem));			\
      84    else   (void) ((type*) 0 == (mem)); 				\
      85  } G_STMT_END
      86  #define g_slice_free_chain(type, mem_chain, next)               \
      87  G_STMT_START {                                                  \
      88    if (1) g_slice_free_chain_with_offset (sizeof (type),		\
      89                   (mem_chain), G_STRUCT_OFFSET (type, next)); 	\
      90    else   (void) ((type*) 0 == (mem_chain));			\
      91  } G_STMT_END
      92  
      93  /* --- internal debugging API --- */
      94  typedef enum {
      95    G_SLICE_CONFIG_ALWAYS_MALLOC = 1,
      96    G_SLICE_CONFIG_BYPASS_MAGAZINES,
      97    G_SLICE_CONFIG_WORKING_SET_MSECS,
      98    G_SLICE_CONFIG_COLOR_INCREMENT,
      99    G_SLICE_CONFIG_CHUNK_SIZES,
     100    G_SLICE_CONFIG_CONTENTION_COUNTER
     101  } GSliceConfig;
     102  
     103  GLIB_DEPRECATED_IN_2_34
     104  void     g_slice_set_config	   (GSliceConfig ckey, gint64 value);
     105  GLIB_DEPRECATED_IN_2_34
     106  gint64   g_slice_get_config	   (GSliceConfig ckey);
     107  GLIB_DEPRECATED_IN_2_34
     108  gint64*  g_slice_get_config_state  (GSliceConfig ckey, gint64 address, guint *n_values);
     109  
     110  #ifdef G_ENABLE_DEBUG
     111  GLIB_AVAILABLE_IN_ALL
     112  void     g_slice_debug_tree_statistics (void);
     113  #endif
     114  
     115  G_END_DECLS
     116  
     117  #endif /* __G_SLICE_H__ */