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.

1 files changed, 12 insertions, 91 deletions

diff --git a/src/system.h b/src/system.h
index c63039c8..5bb06262 100644
--- a/src/system.h
+++ b/src/system.h
@@ -31,20 +31,9 @@
 # define PARAMS(x) ()
 #endif
 
-#ifdef HAVE_UNISTD_H
-# include <fcntl.h>
-# include <unistd.h>
-#else
-# define O_RDONLY 0
-# define SEEK_SET 0
-# define SEEK_CUR 1
-int open(), read(), close();
-#endif
-
+#include <fcntl.h>
+#include <unistd.h>
 #include <errno.h>
-#ifndef errno
-extern int errno;
-#endif
 
 /* Some operating systems treat text and binary files differently.  */
 #ifdef __BEOS__
@@ -74,90 +63,24 @@ extern int errno;
 
 int isdir PARAMS ((char const *));
 
-#ifdef HAVE_DIR_EACCES_BUG
-# ifdef EISDIR
-#  define is_EISDIR(e, f) \
-     ((e) == EISDIR \
-      || ((e) == EACCES && isdir (f) && ((e) = EISDIR, 1)))
-# else
-#  define is_EISDIR(e, f) ((e) == EACCES && isdir (f))
-# endif
-#endif
-
-#ifndef is_EISDIR
-# ifdef EISDIR
-#  define is_EISDIR(e, f) ((e) == EISDIR)
-# else
-#  define is_EISDIR(e, f) 0
-# endif
-#endif
-
-#if STAT_MACROS_BROKEN
-# undef S_ISDIR
-# undef S_ISREG
-#endif
-#if !defined(S_ISDIR) && defined(S_IFDIR)
-# define S_ISDIR(Mode) (((Mode) & S_IFMT) == S_IFDIR)
-#endif
-#if !defined(S_ISREG) && defined(S_IFREG)
-# define S_ISREG(Mode) (((Mode) & S_IFMT) == S_IFREG)
-#endif
-
-#ifdef STDC_HEADERS
-# include <stdlib.h>
+#ifdef EISDIR
+# define is_EISDIR(e, f) ((e) == EISDIR)
 #else
-char *getenv ();
-ptr_t malloc(), realloc(), calloc();
-void free();
+# define is_EISDIR(e, f) 0
 #endif
 
-#if __STDC__
-# include <stddef.h>
-#endif
-#ifdef STDC_HEADERS
-# include <limits.h>
-#endif
-#ifndef CHAR_BIT
-# define CHAR_BIT 8
-#endif
+#include <stdlib.h>
+#include <stddef.h>
+#include <limits.h>
+#include <string.h>
+#include <ctype.h>
+
 /* The extra casts work around common compiler bugs.  */
 #define TYPE_SIGNED(t) (! ((t) 0 < (t) -1))
 #define TYPE_MINIMUM(t) ((t) (TYPE_SIGNED (t) \
 			      ? ~ (t) 0 << (sizeof (t) * CHAR_BIT - 1) \
 			      : (t) 0))
 #define TYPE_MAXIMUM(t) ((t) (~ (t) 0 - TYPE_MINIMUM (t)))
-#ifndef CHAR_MAX
-# define CHAR_MAX TYPE_MAXIMUM (char)
-#endif
-#ifndef INT_MAX
-# define INT_MAX TYPE_MAXIMUM (int)
-#endif
-#ifndef UCHAR_MAX
-# define UCHAR_MAX TYPE_MAXIMUM (unsigned char)
-#endif
-
-#if !defined(STDC_HEADERS) && defined(HAVE_STRING_H) && defined(HAVE_MEMORY_H)
-# include <memory.h>
-#endif
-#if defined(STDC_HEADERS) || defined(HAVE_STRING_H)
-# include <string.h>
-#else
-# include <strings.h>
-# undef strchr
-# define strchr index
-# undef strrchr
-# define strrchr rindex
-# undef memcpy
-# define memcpy(d, s, n) bcopy (s, d, n)
-#endif
-#ifndef HAVE_MEMCHR
-ptr_t memchr();
-#endif
-#if ! defined HAVE_MEMMOVE && ! defined memmove
-# define memmove(d, s, n) bcopy (s, d, n)
-#endif
-
-#include <ctype.h>
 
 #ifndef isgraph
 # define isgraph(C) (isprint(C) && !isspace(C))
@@ -187,9 +110,7 @@ ptr_t memchr();
 #define N_(String) gettext_noop(String)
 #define _(String) gettext(String)
 
-#if HAVE_SETLOCALE
-# include <locale.h>
-#endif
+#include <locale.h>
 
 #ifndef initialize_main
 #define initialize_main(argcp, argvp)