malloc/malloc.h

   1 /* Prototypes and definition for malloc implementation.
   2    Copyright (C) 1996, 1997, 1999, 2000, 2002-2004, 2005, 2007
   3    Free Software Foundation, Inc.
   4    This file is part of the GNU C Library.
   5
   6    The GNU C 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    The GNU C 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 the GNU C Library; if not, write to the Free
  18    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  19    02111-1307 USA.  */
  20
  21 #ifndef _MALLOC_H
  22 #define _MALLOC_H 1
  23
  24 #include <features.h>
  25 #include <stddef.h>
  26 # define __malloc_ptr_t  void *
  27
  28 /* Used by GNU libc internals. */
  29 #define __malloc_size_t size_t
  30 #define __malloc_ptrdiff_t ptrdiff_t
  31
  32 #ifdef __GNUC__
  33
  34 # define __MALLOC_P(args)       args __THROW
  35 /* This macro will be used for functions which might take C++ callback
  36    functions.  */
  37 # define __MALLOC_PMT(args)     args
  38
  39 #else   /* Not GCC.  */
  40
  41 # define __MALLOC_P(args)       args
  42 # define __MALLOC_PMT(args)     args
  43
  44 #endif  /* GCC.  */
  45
  46
  47 __BEGIN_DECLS
  48
  49 /* Allocate SIZE bytes of memory.  */
  50 extern void *malloc __MALLOC_P ((size_t __size)) __attribute_malloc__ __wur;
  51
  52 /* Allocate NMEMB elements of SIZE bytes each, all initialized to 0.  */
  53 extern void *calloc __MALLOC_P ((size_t __nmemb, size_t __size))
  54        __attribute_malloc__ __wur;
  55
  56 /* Re-allocate the previously allocated block in __ptr, making the new
  57    block SIZE bytes long.  */
  58 /* __attribute_malloc__ is not used, because if realloc returns
  59    the same pointer that was passed to it, aliasing needs to be allowed
  60    between objects pointed by the old and new pointers.  */
  61 extern void *realloc __MALLOC_P ((void *__ptr, size_t __size))
  62        __attribute_warn_unused_result__;
  63
  64 /* Free a block allocated by `malloc', `realloc' or `calloc'.  */
  65 extern void free __MALLOC_P ((void *__ptr));
  66
  67 /* Free a block allocated by `calloc'. */
  68 extern void cfree __MALLOC_P ((void *__ptr));
  69
  70 /* Allocate SIZE bytes allocated to ALIGNMENT bytes.  */
  71 extern void *memalign __MALLOC_P ((size_t __alignment, size_t __size))
  72        __attribute_malloc__ __wur;
  73
  74 /* Allocate SIZE bytes on a page boundary.  */
  75 extern void *valloc __MALLOC_P ((size_t __size))
  76        __attribute_malloc__ __wur;
  77
  78 /* Equivalent to valloc(minimum-page-that-holds(n)), that is, round up
  79    __size to nearest pagesize. */
  80 extern void * pvalloc __MALLOC_P ((size_t __size))
  81        __attribute_malloc__ __wur;
  82
  83 /* Underlying allocation function; successive calls should return
  84    contiguous pieces of memory.  */
  85 extern void *(*__morecore) __MALLOC_PMT ((ptrdiff_t __size));
  86
  87 /* Default value of `__morecore'.  */
  88 extern void *__default_morecore __MALLOC_P ((ptrdiff_t __size))
  89        __attribute_malloc__;
  90
  91 /* SVID2/XPG mallinfo structure */
  92
  93 struct mallinfo {
  94   int arena;    /* non-mmapped space allocated from system */
  95   int ordblks;  /* number of free chunks */
  96   int smblks;   /* number of fastbin blocks */
  97   int hblks;    /* number of mmapped regions */
  98   int hblkhd;   /* space in mmapped regions */
  99   int usmblks;  /* maximum total allocated space */
 100   int fsmblks;  /* space available in freed fastbin blocks */
 101   int uordblks; /* total allocated space */
 102   int fordblks; /* total free space */
 103   int keepcost; /* top-most, releasable (via malloc_trim) space */
 104 };
 105
 106 /* Returns a copy of the updated current mallinfo. */
 107 extern struct mallinfo mallinfo __MALLOC_P ((void));
 108
 109 /* SVID2/XPG mallopt options */
 110 #ifndef M_MXFAST
 111 # define M_MXFAST  1    /* maximum request size for "fastbins" */
 112 #endif
 113 #ifndef M_NLBLKS
 114 # define M_NLBLKS  2    /* UNUSED in this malloc */
 115 #endif
 116 #ifndef M_GRAIN
 117 # define M_GRAIN   3    /* UNUSED in this malloc */
 118 #endif
 119 #ifndef M_KEEP
 120 # define M_KEEP    4    /* UNUSED in this malloc */
 121 #endif
 122
 123 /* mallopt options that actually do something */
 124 #define M_TRIM_THRESHOLD    -1
 125 #define M_TOP_PAD           -2
 126 #define M_MMAP_THRESHOLD    -3
 127 #define M_MMAP_MAX          -4
 128 #define M_CHECK_ACTION      -5
 129 #define M_PERTURB           -6
 130
 131 /* General SVID/XPG interface to tunable parameters. */
 132 extern int mallopt __MALLOC_P ((int __param, int __val));
 133
 134 /* Release all but __pad bytes of freed top-most memory back to the
 135    system. Return 1 if successful, else 0. */
 136 extern int malloc_trim __MALLOC_P ((size_t __pad));
 137
 138 /* Report the number of usable allocated bytes associated with allocated
 139    chunk __ptr. */
 140 extern size_t malloc_usable_size __MALLOC_P ((void *__ptr));
 141
 142 /* Prints brief summary statistics on stderr. */
 143 extern void malloc_stats __MALLOC_P ((void));
 144
 145 /* Record the state of all malloc variables in an opaque data structure. */
 146 extern void *malloc_get_state __MALLOC_P ((void));
 147
 148 /* Restore the state of all malloc variables from data obtained with
 149    malloc_get_state(). */
 150 extern int malloc_set_state __MALLOC_P ((void *__ptr));
 151
 152 /* Called once when malloc is initialized; redefining this variable in
 153    the application provides the preferred way to set up the hook
 154    pointers. */
 155 extern void (*__malloc_initialize_hook) __MALLOC_PMT ((void));
 156 /* Hooks for debugging and user-defined versions. */
 157 extern void (*__free_hook) __MALLOC_PMT ((void *__ptr,
 158                                         __const __malloc_ptr_t));
 159 extern void *(*__malloc_hook) __MALLOC_PMT ((size_t __size,
 160                                              __const __malloc_ptr_t));
 161 extern void *(*__realloc_hook) __MALLOC_PMT ((void *__ptr, size_t __size,
 162                                               __const __malloc_ptr_t));
 163 extern void *(*__memalign_hook) __MALLOC_PMT ((size_t __alignment,
 164                                                size_t __size,
 165                                                __const __malloc_ptr_t));
 166 extern void (*__after_morecore_hook) __MALLOC_PMT ((void));
 167
 168 /* Activate a standard set of debugging hooks. */
 169 extern void __malloc_check_init __MALLOC_P ((void));
 170
 171
 172 __END_DECLS
 173
 174 #endif /* malloc.h */