func_mmap_file.m4 | searchcode

/3rd_party/llvm/autoconf/m4/func_mmap_file.m4

https://code.google.com/p/softart/
m4 | 26 lines | 20 code | 0 blank | 6 comment | 0 complexity | 96d4ac0e6d3eb82864dd84f334412c3a MD5 | raw file
Possible License(s): LGPL-2.1, BSD-3-Clause, JSON, MPL-2.0-no-copyleft-exception, GPL-2.0, GPL-3.0, LGPL-3.0, BSD-2-Clause

 1#
 2# Check for the ability to mmap a file.  
 3#
 4AC_DEFUN([AC_FUNC_MMAP_FILE],
 5[AC_CACHE_CHECK(for mmap of files,
 6ac_cv_func_mmap_file,
 7[ AC_LANG_PUSH([C])
 8  AC_RUN_IFELSE([
 9    AC_LANG_PROGRAM([[
10#include <sys/types.h>
11#include <sys/mman.h>
12#include <fcntl.h>
13]],[[
14  int fd;
15  fd = creat ("foo",0777); 
16  fd = (int) mmap (0, 1, PROT_READ, MAP_SHARED, fd, 0);
17  unlink ("foo"); 
18  return (fd != (int) MAP_FAILED);]])],
19  [ac_cv_func_mmap_file=yes],[ac_cv_func_mmap_file=no],[ac_cv_func_mmap_file=no])
20  AC_LANG_POP([C])
21])
22if test "$ac_cv_func_mmap_file" = yes; then
23   AC_DEFINE([HAVE_MMAP_FILE],[],[Define if mmap() can map files into memory])
24   AC_SUBST(MMAP_FILE,[yes])
25fi
26])