replace AC_CHECK_* with gnulib modules

* bootstrap.conf: Add gnulib modules for replacement functions and
headers.
* configure.ac: Remove macros subsumed by gnulib.
* lib/hard-locale.c: Remove guards for headers/functions provided by gnulib.
* lib/regex.c: Likewise.
* lib/savedir.c: Likewise.
* src/dfa.c: Likewise.
* src/dfa.h: Do not look at PROTOTYPES.
* src/grep.c: Likewise.
* src/mbsupport.h: Likewise.
* src/system.h: Likewise.
* m4/mbstate_t.m4: Remove.
* src/getpagesize.h: Remove.

2 files changed, 9 insertions, 29 deletions

diff --git a/m4/.gitignore b/m4/.gitignore
index b0d63087..5e5d4af6 100644
--- a/m4/.gitignore
+++ b/m4/.gitignore
@@ -3,6 +3,7 @@ alloca.m4
 atexit.m4
 btowc.m4
 codeset.m4
+dirent_h.m4
 errno_h.m4
 error.m4
 exitfail.m4
@@ -10,6 +11,7 @@ extensions.m4
 fcntl_h.m4
 fnmatch.m4
 getopt.m4
+getpagesize.m4
 gettext.m4
 glibc2.m4
 glibc21.m4
@@ -36,13 +38,18 @@ localcharset.m4
 locale-fr.m4
 locale-ja.m4
 locale-zh.m4
+locale_h.m4
 lock.m4
 longlong.m4
 malloc.m4
+mbrlen.m4
 mbrtowc.m4
 mbsinit.m4
 mbsrtowcs.m4
+mbstate_t.m4
 memchr.m4
+memmove.m4
+mempcpy.m4
 mmap-anon.m4
 multiarch.m4
 nls.m4
@@ -69,7 +76,9 @@ strtoll.m4
 strtoul.m4
 strtoull.m4
 strtoumax.m4
+sys_stat_h.m4
 threadlib.m4
+time_h.m4
 unistd_h.m4
 visibility.m4
 wchar.m4
diff --git a/m4/mbstate_t.m4 b/m4/mbstate_t.m4
deleted file mode 100644
index b4529271..00000000
--- a/m4/mbstate_t.m4
+++ /dev/null
@@ -1,29 +0,0 @@
-# serial 8
-
-# From Paul Eggert.
-
-# BeOS 5 has <wchar.h> but does not define mbstate_t,
-# so you can't declare an object of that type.
-# Check for this incompatibility with Standard C.
-
-# Include stdlib.h first, because otherwise this test would fail on Linux
-# (at least glibc-2.1.3) because the "_XOPEN_SOURCE 500" definition elicits
-# a syntax error in wchar.h due to the use of undefined __int32_t.
-
-AC_DEFUN([AC_MBSTATE_T],
-  [
-   AC_CHECK_HEADERS(stdlib.h)
-
-   AC_CACHE_CHECK([for mbstate_t], ac_cv_type_mbstate_t,
-    [AC_TRY_COMPILE([
-#if HAVE_STDLIB_H
-# include <stdlib.h>
-#endif
-#include <wchar.h>],
-      [mbstate_t x; return sizeof x;],
-      ac_cv_type_mbstate_t=yes,
-      ac_cv_type_mbstate_t=no)])
-   if test $ac_cv_type_mbstate_t = no; then
-     AC_DEFINE(mbstate_t, int,
-	       [Define to a type if <wchar.h> does not define.])
-   fi])