malloc/malloc.h

   1 /* Prototypes and definition for malloc implementation.
   2    Copyright (C) 1996,1997,1999,2000,2002-2004,2005,2007,2009,2011,2012
   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, see
  18    <http://www.gnu.org/licenses/>.  */
  19
  20 #ifndef _MALLOC_H
  21 #define _MALLOC_H 1
  22
  23 #include <features.h>
  24 #include <stddef.h>
  25 #include <stdio.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 # ifdef _LIBC
  40 #  define __MALLOC_HOOK_VOLATILE
  41 #  define __MALLOC_DEPRECATED
  42 # else
  43 #  define __MALLOC_HOOK_VOLATILE volatile
  44 #  define __MALLOC_DEPRECATED __attribute_deprecated__
  45 # endif
  46
  47 #else   /* Not GCC.  */
  48
  49 # define __MALLOC_P(args)       args
  50 # define __MALLOC_PMT(args)     args
  51 # define __MALLOC_HOOK_VOLATILE
  52 # define __MALLOC_DEPRECATED __attribute_deprecated__
  53
  54 #endif  /* GCC.  */
  55
  56
  57 __BEGIN_DECLS
  58
  59 /* Allocate SIZE bytes of memory.  */
  60 extern void *malloc (size_t __size) __THROW __attribute_malloc__ __wur;
  61
  62 /* Allocate NMEMB elements of SIZE bytes each, all initialized to 0.  */
  63 extern void *calloc (size_t __nmemb, size_t __size)
  64      __THROW __attribute_malloc__ __wur;
  65
  66 /* Re-allocate the previously allocated block in __ptr, making the new
  67    block SIZE bytes long.  */
  68 /* __attribute_malloc__ is not used, because if realloc returns
  69    the same pointer that was passed to it, aliasing needs to be allowed
  70    between objects pointed by the old and new pointers.  */
  71 extern void *realloc (void *__ptr, size_t __size)
  72      __THROW __attribute_warn_unused_result__;
  73
  74 /* Free a block allocated by `malloc', `realloc' or `calloc'.  */
  75 extern void free (void *__ptr) __THROW;
  76
  77 /* Free a block allocated by `calloc'. */
  78 extern void cfree (void *__ptr) __THROW;
  79
  80 /* Allocate SIZE bytes allocated to ALIGNMENT bytes.  */
  81 extern void *memalign (size_t __alignment, size_t __size)
  82      __THROW __attribute_malloc__ __wur;
  83
  84 /* Allocate SIZE bytes on a page boundary.  */
  85 extern void *valloc (size_t __size) __THROW __attribute_malloc__ __wur;
  86
  87 /* Equivalent to valloc(minimum-page-that-holds(n)), that is, round up
  88    __size to nearest pagesize. */
  89 extern void * pvalloc (size_t __size) __THROW __attribute_malloc__ __wur;
  90
  91 /* Underlying allocation function; successive calls should return
  92    contiguous pieces of memory.  */
  93 extern void *(*__morecore) (ptrdiff_t __size);
  94
  95 /* Default value of `__morecore'.  */
  96 extern void *__default_morecore (ptrdiff_t __size)
  97      __THROW __attribute_malloc__;
  98
  99 /* SVID2/XPG mallinfo structure */
 100
 101 struct mallinfo
 102 {
 103   int arena;    /* non-mmapped space allocated from system */
 104   int ordblks;  /* number of free chunks */
 105   int smblks;   /* number of fastbin blocks */
 106   int hblks;    /* number of mmapped regions */
 107   int hblkhd;   /* space in mmapped regions */
 108   int usmblks;  /* maximum total allocated space */
 109   int fsmblks;  /* space available in freed fastbin blocks */
 110   int uordblks; /* total allocated space */
 111   int fordblks; /* total free space */
 112   int keepcost; /* top-most, releasable (via malloc_trim) space */
 113 };
 114
 115 /* Returns a copy of the updated current mallinfo. */
 116 extern struct mallinfo mallinfo (void) __THROW;
 117
 118 /* SVID2/XPG mallopt options */
 119 #ifndef M_MXFAST
 120 # define M_MXFAST  1    /* maximum request size for "fastbins" */
 121 #endif
 122 #ifndef M_NLBLKS
 123 # define M_NLBLKS  2    /* UNUSED in this malloc */
 124 #endif
 125 #ifndef M_GRAIN
 126 # define M_GRAIN   3    /* UNUSED in this malloc */
 127 #endif
 128 #ifndef M_KEEP
 129 # define M_KEEP    4    /* UNUSED in this malloc */
 130 #endif
 131
 132 /* mallopt options that actually do something */
 133 #define M_TRIM_THRESHOLD    -1
 134 #define M_TOP_PAD           -2
 135 #define M_MMAP_THRESHOLD    -3
 136 #define M_MMAP_MAX          -4
 137 #define M_CHECK_ACTION      -5
 138 #define M_PERTURB           -6
 139 #define M_ARENA_TEST        -7
 140 #define M_ARENA_MAX         -8
 141
 142 /* General SVID/XPG interface to tunable parameters. */
 143 extern int mallopt (int __param, int __val) __THROW;
 144
 145 /* Release all but __pad bytes of freed top-most memory back to the
 146    system. Return 1 if successful, else 0. */
 147 extern int malloc_trim (size_t __pad) __THROW;
 148
 149 /* Report the number of usable allocated bytes associated with allocated
 150    chunk __ptr. */
 151 extern size_t malloc_usable_size (void *__ptr) __THROW;
 152
 153 /* Prints brief summary statistics on stderr. */
 154 extern void malloc_stats (void) __THROW;
 155
 156 /* Output information about state of allocator to stream FP.  */
 157 extern int malloc_info (int __options, FILE *__fp) __THROW;
 158
 159 /* Record the state of all malloc variables in an opaque data structure. */
 160 extern void *malloc_get_state (void) __THROW;
 161
 162 /* Restore the state of all malloc variables from data obtained with
 163    malloc_get_state(). */
 164 extern int malloc_set_state (void *__ptr) __THROW;
 165
 166 /* Called once when malloc is initialized; redefining this variable in
 167    the application provides the preferred way to set up the hook
 168    pointers. */
 169 extern void (*__MALLOC_HOOK_VOLATILE __malloc_initialize_hook) (void)
 170      __MALLOC_DEPRECATED;
 171 /* Hooks for debugging and user-defined versions. */
 172 extern void (*__MALLOC_HOOK_VOLATILE __free_hook) (void *__ptr,
 173                                                    const __malloc_ptr_t)
 174      __MALLOC_DEPRECATED;
 175 extern void *(*__MALLOC_HOOK_VOLATILE __malloc_hook) (size_t __size,
 176                                                       const __malloc_ptr_t)
 177      __MALLOC_DEPRECATED;
 178 extern void *(*__MALLOC_HOOK_VOLATILE __realloc_hook) (void *__ptr,
 179                                                        size_t __size,
 180                                                        const __malloc_ptr_t)
 181      __MALLOC_DEPRECATED;
 182 extern void *(*__MALLOC_HOOK_VOLATILE __memalign_hook) (size_t __alignment,
 183                                                         size_t __size,
 184                                                         const __malloc_ptr_t)
 185      __MALLOC_DEPRECATED;
 186 extern void (*__MALLOC_HOOK_VOLATILE __after_morecore_hook) (void);
 187
 188 /* Activate a standard set of debugging hooks. */
 189 extern void __malloc_check_init (void) __THROW __MALLOC_DEPRECATED;
 190
 191
 192 __END_DECLS
 193
 194 #endif /* malloc.h */