malloc/malloc.h

   1 /* Prototypes and definition for malloc implementation.
   2    Copyright (C) 1996, 1997, 1999, 2000, 2002-2004, 2005, 2007, 2009, 2011
   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 # ifdef _LIBC
  41 #  define __MALLOC_HOOK_VOLATILE
  42 # else
  43 #  define __MALLOC_HOOK_VOLATILE
  44 # endif
  45
  46 #else   /* Not GCC.  */
  47
  48 # define __MALLOC_P(args)       args
  49 # define __MALLOC_PMT(args)     args
  50 # define __MALLOC_HOOK_VOLATILE
  51
  52 #endif  /* GCC.  */
  53
  54
  55 __BEGIN_DECLS
  56
  57 /* Allocate SIZE bytes of memory.  */
  58 extern void *malloc (size_t __size) __THROW __attribute_malloc__ __wur;
  59
  60 /* Allocate NMEMB elements of SIZE bytes each, all initialized to 0.  */
  61 extern void *calloc (size_t __nmemb, size_t __size)
  62      __THROW __attribute_malloc__ __wur;
  63
  64 /* Re-allocate the previously allocated block in __ptr, making the new
  65    block SIZE bytes long.  */
  66 /* __attribute_malloc__ is not used, because if realloc returns
  67    the same pointer that was passed to it, aliasing needs to be allowed
  68    between objects pointed by the old and new pointers.  */
  69 extern void *realloc (void *__ptr, size_t __size)
  70      __THROW __attribute_warn_unused_result__;
  71
  72 /* Free a block allocated by `malloc', `realloc' or `calloc'.  */
  73 extern void free (void *__ptr) __THROW;
  74
  75 /* Free a block allocated by `calloc'. */
  76 extern void cfree (void *__ptr) __THROW;
  77
  78 /* Allocate SIZE bytes allocated to ALIGNMENT bytes.  */
  79 extern void *memalign (size_t __alignment, size_t __size)
  80      __THROW __attribute_malloc__ __wur;
  81
  82 /* Allocate SIZE bytes on a page boundary.  */
  83 extern void *valloc (size_t __size) __THROW __attribute_malloc__ __wur;
  84
  85 /* Equivalent to valloc(minimum-page-that-holds(n)), that is, round up
  86    __size to nearest pagesize. */
  87 extern void * pvalloc (size_t __size) __THROW __attribute_malloc__ __wur;
  88
  89 /* Underlying allocation function; successive calls should return
  90    contiguous pieces of memory.  */
  91 extern void *(*__morecore) (ptrdiff_t __size);
  92
  93 /* Default value of `__morecore'.  */
  94 extern void *__default_morecore (ptrdiff_t __size)
  95      __THROW __attribute_malloc__;
  96
  97 /* SVID2/XPG mallinfo structure */
  98
  99 struct mallinfo
 100 {
 101   int arena;    /* non-mmapped space allocated from system */
 102   int ordblks;  /* number of free chunks */
 103   int smblks;   /* number of fastbin blocks */
 104   int hblks;    /* number of mmapped regions */
 105   int hblkhd;   /* space in mmapped regions */
 106   int usmblks;  /* maximum total allocated space */
 107   int fsmblks;  /* space available in freed fastbin blocks */
 108   int uordblks; /* total allocated space */
 109   int fordblks; /* total free space */
 110   int keepcost; /* top-most, releasable (via malloc_trim) space */
 111 };
 112
 113 /* Returns a copy of the updated current mallinfo. */
 114 extern struct mallinfo mallinfo (void) __THROW;
 115
 116 /* SVID2/XPG mallopt options */
 117 #ifndef M_MXFAST
 118 # define M_MXFAST  1    /* maximum request size for "fastbins" */
 119 #endif
 120 #ifndef M_NLBLKS
 121 # define M_NLBLKS  2    /* UNUSED in this malloc */
 122 #endif
 123 #ifndef M_GRAIN
 124 # define M_GRAIN   3    /* UNUSED in this malloc */
 125 #endif
 126 #ifndef M_KEEP
 127 # define M_KEEP    4    /* UNUSED in this malloc */
 128 #endif
 129
 130 /* mallopt options that actually do something */
 131 #define M_TRIM_THRESHOLD    -1
 132 #define M_TOP_PAD           -2
 133 #define M_MMAP_THRESHOLD    -3
 134 #define M_MMAP_MAX          -4
 135 #define M_CHECK_ACTION      -5
 136 #define M_PERTURB           -6
 137 #define M_ARENA_TEST        -7
 138 #define M_ARENA_MAX         -8
 139
 140 /* General SVID/XPG interface to tunable parameters. */
 141 extern int mallopt (int __param, int __val) __THROW;
 142
 143 /* Release all but __pad bytes of freed top-most memory back to the
 144    system. Return 1 if successful, else 0. */
 145 extern int malloc_trim (size_t __pad) __THROW;
 146
 147 /* Report the number of usable allocated bytes associated with allocated
 148    chunk __ptr. */
 149 extern size_t malloc_usable_size (void *__ptr) __THROW;
 150
 151 /* Prints brief summary statistics on stderr. */
 152 extern void malloc_stats (void) __THROW;
 153
 154 /* Output information about state of allocator to stream FP.  */
 155 extern int malloc_info (int __options, FILE *__fp) __THROW;
 156
 157 /* Record the state of all malloc variables in an opaque data structure. */
 158 extern void *malloc_get_state (void) __THROW;
 159
 160 /* Restore the state of all malloc variables from data obtained with
 161    malloc_get_state(). */
 162 extern int malloc_set_state (void *__ptr) __THROW;
 163
 164 /* Called once when malloc is initialized; redefining this variable in
 165    the application provides the preferred way to set up the hook
 166    pointers. */
 167 extern void (*__malloc_initialize_hook) (void);
 168 /* Hooks for debugging and user-defined versions. */
 169 extern void (*__MALLOC_HOOK_VOLATILE __free_hook) (void *__ptr,
 170                                                    __const __malloc_ptr_t);
 171 extern void *(*__MALLOC_HOOK_VOLATILE __malloc_hook) (size_t __size,
 172                                                       __const __malloc_ptr_t);
 173 extern void *(*__MALLOC_HOOK_VOLATILE __realloc_hook) (void *__ptr,
 174                                                        size_t __size,
 175                                                        __const __malloc_ptr_t);
 176 extern void *(*__MALLOC_HOOK_VOLATILE __memalign_hook) (size_t __alignment,
 177                                                         size_t __size,
 178                                                         __const __malloc_ptr_t);
 179 extern void (*__MALLOC_HOOK_VOLATILE __after_morecore_hook) (void);
 180
 181 /* Activate a standard set of debugging hooks. */
 182 extern void __malloc_check_init (void) __THROW;
 183
 184
 185 __END_DECLS
 186
 187 #endif /* malloc.h */