misc/sys/mman.h

   1 /* Definitions for BSD-style memory management.
   2    Copyright (C) 1994-2015 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <http://www.gnu.org/licenses/>.  */
  18
  19 #ifndef _SYS_MMAN_H
  20 #define _SYS_MMAN_H     1
  21
  22 #include <features.h>
  23 #include <bits/types.h>
  24 #define __need_size_t
  25 #include <stddef.h>
  26
  27 #ifndef __off_t_defined
  28 # ifndef __USE_FILE_OFFSET64
  29 typedef __off_t off_t;
  30 # else
  31 typedef __off64_t off_t;
  32 # endif
  33 # define __off_t_defined
  34 #endif
  35
  36 #ifndef __mode_t_defined
  37 typedef __mode_t mode_t;
  38 # define __mode_t_defined
  39 #endif
  40
  41 #include <bits/mman.h>
  42
  43 /* Return value of `mmap' in case of an error.  */
  44 #define MAP_FAILED      ((void *) -1)
  45
  46 __BEGIN_DECLS
  47 /* Map addresses starting near ADDR and extending for LEN bytes.  from
  48    OFFSET into the file FD describes according to PROT and FLAGS.  If ADDR
  49    is nonzero, it is the desired mapping address.  If the MAP_FIXED bit is
  50    set in FLAGS, the mapping will be at ADDR exactly (which must be
  51    page-aligned); otherwise the system chooses a convenient nearby address.
  52    The return value is the actual mapping address chosen or MAP_FAILED
  53    for errors (in which case `errno' is set).  A successful `mmap' call
  54    deallocates any previous mapping for the affected region.  */
  55
  56 #ifndef __USE_FILE_OFFSET64
  57 extern void *mmap (void *__addr, size_t __len, int __prot,
  58                    int __flags, int __fd, __off_t __offset) __THROW;
  59 #else
  60 # ifdef __REDIRECT_NTH
  61 extern void * __REDIRECT_NTH (mmap,
  62                               (void *__addr, size_t __len, int __prot,
  63                                int __flags, int __fd, __off64_t __offset),
  64                               mmap64);
  65 # else
  66 #  define mmap mmap64
  67 # endif
  68 #endif
  69 #ifdef __USE_LARGEFILE64
  70 extern void *mmap64 (void *__addr, size_t __len, int __prot,
  71                      int __flags, int __fd, __off64_t __offset) __THROW;
  72 #endif
  73
  74 /* Deallocate any mapping for the region starting at ADDR and extending LEN
  75    bytes.  Returns 0 if successful, -1 for errors (and sets errno).  */
  76 extern int munmap (void *__addr, size_t __len) __THROW;
  77
  78 /* Change the memory protection of the region starting at ADDR and
  79    extending LEN bytes to PROT.  Returns 0 if successful, -1 for errors
  80    (and sets errno).  */
  81 extern int mprotect (void *__addr, size_t __len, int __prot) __THROW;
  82
  83 /* Synchronize the region starting at ADDR and extending LEN bytes with the
  84    file it maps.  Filesystem operations on a file being mapped are
  85    unpredictable before this is done.  Flags are from the MS_* set.
  86
  87    This function is a cancellation point and therefore not marked with
  88    __THROW.  */
  89 extern int msync (void *__addr, size_t __len, int __flags);
  90
  91 #ifdef __USE_MISC
  92 /* Advise the system about particular usage patterns the program follows
  93    for the region starting at ADDR and extending LEN bytes.  */
  94 extern int madvise (void *__addr, size_t __len, int __advice) __THROW;
  95 #endif
  96 #ifdef __USE_XOPEN2K
  97 /* This is the POSIX name for this function.  */
  98 extern int posix_madvise (void *__addr, size_t __len, int __advice) __THROW;
  99 #endif
 100
 101 /* Guarantee all whole pages mapped by the range [ADDR,ADDR+LEN) to
 102    be memory resident.  */
 103 extern int mlock (const void *__addr, size_t __len) __THROW;
 104
 105 /* Unlock whole pages previously mapped by the range [ADDR,ADDR+LEN).  */
 106 extern int munlock (const void *__addr, size_t __len) __THROW;
 107
 108 /* Cause all currently mapped pages of the process to be memory resident
 109    until unlocked by a call to the `munlockall', until the process exits,
 110    or until the process calls `execve'.  */
 111 extern int mlockall (int __flags) __THROW;
 112
 113 /* All currently mapped pages of the process' address space become
 114    unlocked.  */
 115 extern int munlockall (void) __THROW;
 116
 117 #ifdef __USE_MISC
 118 /* mincore returns the memory residency status of the pages in the
 119    current process's address space specified by [start, start + len).
 120    The status is returned in a vector of bytes.  The least significant
 121    bit of each byte is 1 if the referenced page is in memory, otherwise
 122    it is zero.  */
 123 extern int mincore (void *__start, size_t __len, unsigned char *__vec)
 124      __THROW;
 125 #endif
 126
 127 #ifdef __USE_GNU
 128 /* Remap pages mapped by the range [ADDR,ADDR+OLD_LEN) to new length
 129    NEW_LEN.  If MREMAP_MAYMOVE is set in FLAGS the returned address
 130    may differ from ADDR.  If MREMAP_FIXED is set in FLAGS the function
 131    takes another parameter which is a fixed address at which the block
 132    resides after a successful call.  */
 133 extern void *mremap (void *__addr, size_t __old_len, size_t __new_len,
 134                      int __flags, ...) __THROW;
 135
 136 /* Remap arbitrary pages of a shared backing store within an existing
 137    VMA.  */
 138 extern int remap_file_pages (void *__start, size_t __size, int __prot,
 139                              size_t __pgoff, int __flags) __THROW;
 140 #endif
 141
 142
 143 /* Open shared memory segment.  */
 144 extern int shm_open (const char *__name, int __oflag, mode_t __mode);
 145
 146 /* Remove shared memory segment.  */
 147 extern int shm_unlink (const char *__name);
 148
 149 __END_DECLS
 150
 151 #endif  /* sys/mman.h */