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Diffstat (limited to 'm4/mmap-anon.m4')
| -rw-r--r-- | m4/mmap-anon.m4 | 48 |
1 files changed, 48 insertions, 0 deletions
diff --git a/m4/mmap-anon.m4 b/m4/mmap-anon.m4 new file mode 100644 index 0000000..fd8a537 --- /dev/null +++ b/m4/mmap-anon.m4 @@ -0,0 +1,48 @@ +# mmap-anon.m4 serial 3 +dnl Copyright (C) 2005 Free Software Foundation, Inc. +dnl This file is free software; the Free Software Foundation +dnl gives unlimited permission to copy and/or distribute it, +dnl with or without modifications, as long as this notice is preserved. + +AC_DEFUN([gl_FUNC_MMAP_ANON], +[ + dnl Work around a bug of AC_EGREP_CPP in autoconf-2.57. + AC_REQUIRE([AC_PROG_CPP]) + AC_REQUIRE([AC_PROG_EGREP]) + + dnl Persuade glibc <sys/mman.h> to define MAP_ANONYMOUS. + AC_REQUIRE([AC_GNU_SOURCE]) + + # Check for mmap() + AC_FUNC_MMAP + + # Try to allow MAP_ANONYMOUS. + gl_have_mmap_anonymous=no + if test $ac_cv_func_mmap_fixed_mapped = yes; then + AC_MSG_CHECKING([for MAP_ANONYMOUS]) + AC_EGREP_CPP([I cant identify this map.], [ +#include <sys/mman.h> +#ifdef MAP_ANONYMOUS + I cant identify this map. +#endif +], + [gl_have_mmap_anonymous=yes]) + if test $gl_have_mmap_anonymous != yes; then + AC_EGREP_CPP([I cant identify this map.], [ +#include <sys/mman.h> +#ifdef MAP_ANON + I cant identify this map. +#endif +], + [AC_DEFINE(MAP_ANONYMOUS, MAP_ANON, + [Define to a substitute value for mmap()'s MAP_ANONYMOUS flag.]) + gl_have_mmap_anonymous=yes]) + fi + AC_MSG_RESULT($gl_have_mmap_anonymous) + if test $gl_have_mmap_anonymous = yes; then + AC_DEFINE(HAVE_MAP_ANONYMOUS, 1, + [Define to 1 if mmap()'s MAP_ANONYMOUS flag is available after including + config.h and <sys/mman.h>.]) + fi + fi +]) |