sim: dv-cfi: check for posix_fallocate

Some systems (like OS X) do not have posix_fallocate.  Add a configure
check for it before we try to use it.  This is less work than trying
to support old systems.

URL: http://sourceware.org/bugzilla/show_bug.cgi?id=13161
Signed-off-by: Mike Frysinger <vapier@gentoo.org>

sim/common/ChangeLog

@@ -1,3 +1,10 @@
+2011-11-07  Mike Frysinger  <vapier@gentoo.org>
+
+	PR sim/13161
+	* configure.ac (AC_CHECK_FUNCS): Add posix_fallocate.
+	* configure, config.in: Regenerate.
+	* dv-cfi.c (attach_cfi_regs): Check for HAVE_POSIX_FALLOCATE.
+
 2011-10-19  Mike Frysinger  <vapier@gentoo.org>
 
 	* acinclude.m4: Call AC_CHECK_LIB when $hardware contains cfi.

sim/common/config.in

@@ -43,6 +43,9 @@
 /* Define to 1 if you have the `munmap' function. */
 #undef HAVE_MUNMAP
 
+/* Define to 1 if you have the `posix_fallocate' function. */
+#undef HAVE_POSIX_FALLOCATE
+
 /* Define to 1 if you have the `sigaction' function. */
 #undef HAVE_SIGACTION
 

sim/common/configure

@@ -4393,7 +4393,7 @@ fi
 
 done
 
-for ac_func in mmap munmap lstat truncate ftruncate
+for ac_func in mmap munmap lstat truncate ftruncate posix_fallocate
 do :
   as_ac_var=`$as_echo "ac_cv_func_$ac_func" | $as_tr_sh`
 ac_fn_c_check_func "$LINENO" "$ac_func" "$as_ac_var"

sim/common/configure.ac

@@ -34,7 +34,7 @@ AC_SUBST(TARGET_SUBDIR)
 
 # These aren't all needed yet, but will be eventually.
 AC_CHECK_HEADERS(stdlib.h string.h strings.h time.h sys/times.h sys/stat.h sys/mman.h)
-AC_CHECK_FUNCS(mmap munmap lstat truncate ftruncate)
+AC_CHECK_FUNCS(mmap munmap lstat truncate ftruncate posix_fallocate)
 AC_CHECK_MEMBERS([[struct stat.st_dev], [struct stat.st_ino],
 [struct stat.st_mode], [struct stat.st_nlink], [struct stat.st_uid],
 [struct stat.st_gid], [struct stat.st_rdev], [struct stat.st_size],

sim/common/dv-cfi.c

@@ -727,7 +727,7 @@ attach_cfi_regs (struct hw *me, struct cfi *cfi)
   /* Figure out where our initial flash data is coming from.  */
   if (fd != -1 && fd_writable)
     {
-#ifdef HAVE_MMAP
+#if defined (HAVE_MMAP) && defined (HAVE_POSIX_FALLOCATE)
       posix_fallocate (fd, 0, cfi->dev_size);
 
       cfi->mmap = mmap (NULL, cfi->dev_size,