malloc/malloc.h

   1 /* Prototypes and definition for malloc implementation.
   2    Copyright (C) 1996, 1997, 1999, 2000, 2002-2004, 2005, 2007, 2009
   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 #include <stdio.h>
  27 # define __malloc_ptr_t  void *
  28
  29 /* Used by GNU libc internals. */
  30 #define __malloc_size_t size_t
  31 #define __malloc_ptrdiff_t ptrdiff_t
  32
  33 #ifdef __GNUC__
  34
  35 # define __MALLOC_P(args)       args __THROW
  36 /* This macro will be used for functions which might take C++ callback
  37    functions.  */
  38 # define __MALLOC_PMT(args)     args
  39
  40 #else   /* Not GCC.  */
  41
  42 # define __MALLOC_P(args)       args
  43 # define __MALLOC_PMT(args)     args
  44
  45 #endif  /* GCC.  */
  46
  47
  48 __BEGIN_DECLS
  49
  50 /* Allocate SIZE bytes of memory.  */
  51 extern void *malloc __MALLOC_P ((size_t __size)) __attribute_malloc__ __wur;
  52
  53 /* Allocate NMEMB elements of SIZE bytes each, all initialized to 0.  */
  54 extern void *calloc __MALLOC_P ((size_t __nmemb, size_t __size))
  55        __attribute_malloc__ __wur;
  56
  57 /* Re-allocate the previously allocated block in __ptr, making the new
  58    block SIZE bytes long.  */
  59 /* __attribute_malloc__ is not used, because if realloc returns
  60    the same pointer that was passed to it, aliasing needs to be allowed
  61    between objects pointed by the old and new pointers.  */
  62 extern void *realloc __MALLOC_P ((void *__ptr, size_t __size))
  63        __attribute_warn_unused_result__;
  64
  65 /* Free a block allocated by `malloc', `realloc' or `calloc'.  */
  66 extern void free __MALLOC_P ((void *__ptr));
  67
  68 /* Free a block allocated by `calloc'. */
  69 extern void cfree __MALLOC_P ((void *__ptr));
  70
  71 /* Allocate SIZE bytes allocated to ALIGNMENT bytes.  */
  72 extern void *memalign __MALLOC_P ((size_t __alignment, size_t __size))
  73        __attribute_malloc__ __wur;
  74
  75 /* Allocate SIZE bytes on a page boundary.  */
  76 extern void *valloc __MALLOC_P ((size_t __size))
  77        __attribute_malloc__ __wur;
  78
  79 /* Equivalent to valloc(minimum-page-that-holds(n)), that is, round up
  80    __size to nearest pagesize. */
  81 extern void * pvalloc __MALLOC_P ((size_t __size))
  82        __attribute_malloc__ __wur;
  83
  84 /* Underlying allocation function; successive calls should return
  85    contiguous pieces of memory.  */
  86 extern void *(*__morecore) __MALLOC_PMT ((ptrdiff_t __size));
  87
  88 /* Default value of `__morecore'.  */
  89 extern void *__default_morecore __MALLOC_P ((ptrdiff_t __size))
  90        __attribute_malloc__;
  91
  92 /* SVID2/XPG mallinfo structure */
  93
  94 struct mallinfo {
  95   int arena;    /* non-mmapped space allocated from system */
  96   int ordblks;  /* number of free chunks */
  97   int smblks;   /* number of fastbin blocks */
  98   int hblks;    /* number of mmapped regions */
  99   int hblkhd;   /* space in mmapped regions */
 100   int usmblks;  /* maximum total allocated space */
 101   int fsmblks;  /* space available in freed fastbin blocks */
 102   int uordblks; /* total allocated space */
 103   int fordblks; /* total free space */
 104   int keepcost; /* top-most, releasable (via malloc_trim) space */
 105 };
 106
 107 /* Returns a copy of the updated current mallinfo. */
 108 extern struct mallinfo mallinfo __MALLOC_P ((void));
 109
 110 /* SVID2/XPG mallopt options */
 111 #ifndef M_MXFAST
 112 # define M_MXFAST  1    /* maximum request size for "fastbins" */
 113 #endif
 114 #ifndef M_NLBLKS
 115 # define M_NLBLKS  2    /* UNUSED in this malloc */
 116 #endif
 117 #ifndef M_GRAIN
 118 # define M_GRAIN   3    /* UNUSED in this malloc */
 119 #endif
 120 #ifndef M_KEEP
 121 # define M_KEEP    4    /* UNUSED in this malloc */
 122 #endif
 123
 124 /* mallopt options that actually do something */
 125 #define M_TRIM_THRESHOLD    -1
 126 #define M_TOP_PAD           -2
 127 #define M_MMAP_THRESHOLD    -3
 128 #define M_MMAP_MAX          -4
 129 #define M_CHECK_ACTION      -5
 130 #define M_PERTURB           -6
 131 #define M_ARENA_TEST        -7
 132 #define M_ARENA_MAX         -8
 133
 134 /* General SVID/XPG interface to tunable parameters. */
 135 extern int mallopt __MALLOC_P ((int __param, int __val));
 136
 137 /* Release all but __pad bytes of freed top-most memory back to the
 138    system. Return 1 if successful, else 0. */
 139 extern int malloc_trim __MALLOC_P ((size_t __pad));
 140
 141 /* Report the number of usable allocated bytes associated with allocated
 142    chunk __ptr. */
 143 extern size_t malloc_usable_size __MALLOC_P ((void *__ptr));
 144
 145 /* Prints brief summary statistics on stderr. */
 146 extern void malloc_stats __MALLOC_P ((void));
 147
 148 /* Output information about state of allocator to stream FP.  */
 149 extern int malloc_info (int __options, FILE *__fp);
 150
 151 /* Record the state of all malloc variables in an opaque data structure. */
 152 extern void *malloc_get_state __MALLOC_P ((void));
 153
 154 /* Restore the state of all malloc variables from data obtained with
 155    malloc_get_state(). */
 156 extern int malloc_set_state __MALLOC_P ((void *__ptr));
 157
 158 /* Called once when malloc is initialized; redefining this variable in
 159    the application provides the preferred way to set up the hook
 160    pointers. */
 161 extern void (*__malloc_initialize_hook) __MALLOC_PMT ((void));
 162 /* Hooks for debugging and user-defined versions. */
 163 extern void (*__free_hook) __MALLOC_PMT ((void *__ptr,
 164                                         __const __malloc_ptr_t));
 165 extern void *(*__malloc_hook) __MALLOC_PMT ((size_t __size,
 166                                              __const __malloc_ptr_t));
 167 extern void *(*__realloc_hook) __MALLOC_PMT ((void *__ptr, size_t __size,
 168                                               __const __malloc_ptr_t));
 169 extern void *(*__memalign_hook) __MALLOC_PMT ((size_t __alignment,
 170                                                size_t __size,
 171                                                __const __malloc_ptr_t));
 172 extern void (*__after_morecore_hook) __MALLOC_PMT ((void));
 173
 174 /* Activate a standard set of debugging hooks. */
 175 extern void __malloc_check_init __MALLOC_P ((void));
 176
 177
 178 __END_DECLS
 179
 180 #endif /* malloc.h */