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.

4 files changed, 23 insertions, 65 deletions

diff --git a/lib/.gitignore b/lib/.gitignore
index 1015ec80..952e3dff 100644
--- a/lib/.gitignore
+++ b/lib/.gitignore
@@ -4,6 +4,8 @@ alloca.in.h
 atexit.c
 btowc.c
 config.charset
+dirent.h
+dirent.in.h
 dummy.c
 errno.h
 errno.in.h
@@ -20,6 +22,7 @@ getopt.h
 getopt.in.h
 getopt1.c
 getopt_int.h
+getpagesize.c
 gettext.h
 gnulib.mk
 intprops.h
@@ -27,13 +30,18 @@ inttypes.h
 inttypes.in.h
 localcharset.c
 localcharset.h
+locale.h
+locale.in.h
 malloc.c
+mbrlen.c
 mbrtowc.c
 mbsinit.c
 mbsrtowcs-state.c
 mbsrtowcs.c
 memchr.c
 memchr.valgrind
+memmove.c
+mempcpy.c
 obstack.c
 obstack.h
 quotearg.c
@@ -69,6 +77,11 @@ strtol.c
 strtoll.c
 strtoul.c
 strtoull.c
+sys
+sys_stat.h
+sys_stat.in.h
+time.h
+time.in.h
 unistd.h
 unistd.in.h
 verify.h
diff --git a/lib/hard-locale.c b/lib/hard-locale.c
index 79822e7e..eef13f84 100644
--- a/lib/hard-locale.c
+++ b/lib/hard-locale.c
@@ -15,36 +15,10 @@
    along with this program; if not, write to the Free Software Foundation,
    Inc., 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA.  */
 
-#if HAVE_CONFIG_H
-# include <config.h>
-#endif
-
-#ifndef __GNUC__
-# ifdef HAVE_ALLOCA_H
-#  include <alloca.h>
-# else
-#  ifdef _AIX
- #  pragma alloca
-#  else
-#   ifdef _WIN32
-#    include <malloc.h>
-#    include <io.h>
-#   else
-#    ifndef alloca
-char *alloca ();
-#    endif
-#   endif
-#  endif
-# endif
-#endif
-
-#if HAVE_LOCALE_H
-# include <locale.h>
-#endif
-
-#if HAVE_STRING_H
-# include <string.h>
-#endif
+#include <config.h>
+#include <alloca.h>
+#include <locale.h>
+#include <string.h>
 
 /* Return nonzero if the current CATEGORY locale is hard, i.e. if you
    can't get away with assuming traditional C or POSIX behavior.  */
diff --git a/lib/regex.c b/lib/regex.c
index fb7df666..6ad5c539 100644
--- a/lib/regex.c
+++ b/lib/regex.c
@@ -46,7 +46,7 @@
 # include <sys/types.h>
 #endif
 
-#define WIDE_CHAR_SUPPORT (HAVE_WCTYPE_H && HAVE_WCHAR_H && HAVE_BTOWC)
+#define WIDE_CHAR_SUPPORT (HAVE_WCTYPE_H && HAVE_WCHAR_H)
 
 /* For platform which support the ISO C amendement 1 functionality we
    support user defined character classes.  */
diff --git a/lib/savedir.c b/lib/savedir.c
index 9c46b66e..a7e02e8b 100644
--- a/lib/savedir.c
+++ b/lib/savedir.c
@@ -23,25 +23,9 @@
 #endif
 
 #include <sys/types.h>
-
-#if HAVE_UNISTD_H
-# include <unistd.h>
-#endif
-
-#if HAVE_DIRENT_H
-# include <dirent.h>
-#else
-# define dirent direct
-# if HAVE_SYS_NDIR_H
-#  include <sys/ndir.h>
-# endif
-# if HAVE_SYS_DIR_H
-#  include <sys/dir.h>
-# endif
-# if HAVE_NDIR_H
-#  include <ndir.h>
-# endif
-#endif
+#include <unistd.h>
+#include <dirent.h>
+#include <stddef.h>
 
 #ifdef CLOSEDIR_VOID
 /* Fake a return value. */
@@ -50,21 +34,8 @@
 # define CLOSEDIR(d) closedir (d)
 #endif
 
-#ifdef STDC_HEADERS
-# include <stdlib.h>
-# include <string.h>
-#else
-char *malloc ();
-char *realloc ();
-#endif
-#ifndef NULL
-# define NULL 0
-#endif
-
-#ifndef stpcpy
-char *stpcpy ();
-#endif
-
+#include <stdlib.h>
+#include <string.h>
 #include <fnmatch.h>
 #include "savedir.h"