Add some missing checks to configure.

.gitignore

@@ -1,6 +1,7 @@
 *.a
 *.o
 Makefile
+/autom4te.cache/
 /config.cache
 /config.log
 /config.status

acinclude.m4

@@ -427,7 +427,9 @@ AC_ARG_WITH(termlib,
  AC_MSG_RESULT($with_termlib)
  test x"$with_termlib" = xyes && with_termlib="terminfo mytinfo termlib termcap tinfo ncurses curses"
  for lib in $with_termlib; do
-   AC_CHECK_LIB($lib, tgetent, [W3M_LIBS="$W3M_LIBS -l$lib"; break])
+   AC_CHECK_LIB($lib, tgetent,
+                [W3M_LIBS="$W3M_LIBS -l$lib"; break],
+                [test "$lib" = curses && AC_MSG_ERROR([No terminal library found])])
  done
 ])
 #
@@ -774,6 +776,7 @@ AC_DEFUN([AC_W3M_IMAGE],
    fi
   fi
   if test x"$fb" = xyes; then
+   AC_CHECK_HEADER(linux/fb.h, [], [AC_MSG_ERROR([linux/fb.h not found])])
    if test x"$have_imlib2" = xyes; then
      AC_DEFINE(USE_W3MIMG_FB)
      IMGOBJS="$IMGOBJS fb/fb_w3mimg.o fb/fb.o fb/fb_img.o"

configure

@@ -4118,39 +4118,35 @@ else
   RANLIB="$ac_cv_prog_RANLIB"
 fi
 
-for ac_prog in perl
-do
-  # Extract the first word of "$ac_prog", so it can be a program name with args.
-set dummy $ac_prog; ac_word=$2
+# Extract the first word of "perl", so it can be a program name with args.
+set dummy perl; ac_word=$2
 { $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
 $as_echo_n "checking for $ac_word... " >&6; }
-if ${ac_cv_path_PERL+:} false; then :
+if ${ac_cv_prog_PERL+:} false; then :
   $as_echo_n "(cached) " >&6
 else
-  case $PERL in
-  [\\/]* | ?:[\\/]*)
-  ac_cv_path_PERL="$PERL" # Let the user override the test with a path.
-  ;;
-  *)
-  as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
+  if test -n "$PERL"; then
+  ac_cv_prog_PERL="$PERL" # Let the user override the test.
+else
+as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
 for as_dir in $PATH
 do
   IFS=$as_save_IFS
   test -z "$as_dir" && as_dir=.
     for ac_exec_ext in '' $ac_executable_extensions; do
   if as_fn_executable_p "$as_dir/$ac_word$ac_exec_ext"; then
-    ac_cv_path_PERL="$as_dir/$ac_word$ac_exec_ext"
+    ac_cv_prog_PERL="$(command -v perl)"
     $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
     break 2
   fi
 done
   done
 IFS=$as_save_IFS
 
-  ;;
-esac
+  test -z "$ac_cv_prog_PERL" && ac_cv_prog_PERL="no"
+fi
 fi
-PERL=$ac_cv_path_PERL
+PERL=$ac_cv_prog_PERL
 if test -n "$PERL"; then
   { $as_echo "$as_me:${as_lineno-$LINENO}: result: $PERL" >&5
 $as_echo "$PERL" >&6; }
@@ -4160,10 +4156,7 @@ $as_echo "no" >&6; }
 fi
 
 
-  test -n "$PERL" && break
-done
-test -n "$PERL" || PERL="/usr/local/bin/perl"
-
+test "$PERL" == "no" && as_fn_error $? "Required program 'perl' not found." "$LINENO" 5
 for ac_prog in nkf
 do
   # Extract the first word of "$ac_prog", so it can be a program name with args.
@@ -7448,6 +7441,135 @@ fi
 { $as_echo "$as_me:${as_lineno-$LINENO}: result: $enable_bgcolor" >&5
 $as_echo "$enable_bgcolor" >&6; }
 
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for ANSI C header files" >&5
+$as_echo_n "checking for ANSI C header files... " >&6; }
+if ${ac_cv_header_stdc+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+#include <stdlib.h>
+#include <stdarg.h>
+#include <string.h>
+#include <float.h>
+
+int
+main ()
+{
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+  ac_cv_header_stdc=yes
+else
+  ac_cv_header_stdc=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+
+if test $ac_cv_header_stdc = yes; then
+  # SunOS 4.x string.h does not declare mem*, contrary to ANSI.
+  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+#include <string.h>
+
+_ACEOF
+if (eval "$ac_cpp conftest.$ac_ext") 2>&5 |
+  $EGREP "memchr" >/dev/null 2>&1; then :
+
+else
+  ac_cv_header_stdc=no
+fi
+rm -f conftest*
+
+fi
+
+if test $ac_cv_header_stdc = yes; then
+  # ISC 2.0.2 stdlib.h does not declare free, contrary to ANSI.
+  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+#include <stdlib.h>
+
+_ACEOF
+if (eval "$ac_cpp conftest.$ac_ext") 2>&5 |
+  $EGREP "free" >/dev/null 2>&1; then :
+
+else
+  ac_cv_header_stdc=no
+fi
+rm -f conftest*
+
+fi
+
+if test $ac_cv_header_stdc = yes; then
+  # /bin/cc in Irix-4.0.5 gets non-ANSI ctype macros unless using -ansi.
+  if test "$cross_compiling" = yes; then :
+  :
+else
+  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+#include <ctype.h>
+#include <stdlib.h>
+#if ((' ' & 0x0FF) == 0x020)
+# define ISLOWER(c) ('a' <= (c) && (c) <= 'z')
+# define TOUPPER(c) (ISLOWER(c) ? 'A' + ((c) - 'a') : (c))
+#else
+# define ISLOWER(c) \
+		   (('a' <= (c) && (c) <= 'i') \
+		     || ('j' <= (c) && (c) <= 'r') \
+		     || ('s' <= (c) && (c) <= 'z'))
+# define TOUPPER(c) (ISLOWER(c) ? ((c) | 0x40) : (c))
+#endif
+
+#define XOR(e, f) (((e) && !(f)) || (!(e) && (f)))
+int
+main ()
+{
+  int i;
+  for (i = 0; i < 256; i++)
+    if (XOR (islower (i), ISLOWER (i))
+	|| toupper (i) != TOUPPER (i))
+      return 2;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_run "$LINENO"; then :
+
+else
+  ac_cv_header_stdc=no
+fi
+rm -f core *.core core.conftest.* gmon.out bb.out conftest$ac_exeext \
+  conftest.$ac_objext conftest.beam conftest.$ac_ext
+fi
+
+fi
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_header_stdc" >&5
+$as_echo "$ac_cv_header_stdc" >&6; }
+if test $ac_cv_header_stdc = yes; then
+
+$as_echo "#define STDC_HEADERS 1" >>confdefs.h
+
+fi
+
+# On IRIX 5.3, sys/types and inttypes.h are conflicting.
+for ac_header in sys/types.h sys/stat.h stdlib.h string.h memory.h strings.h \
+		  inttypes.h stdint.h unistd.h
+do :
+  as_ac_Header=`$as_echo "ac_cv_header_$ac_header" | $as_tr_sh`
+ac_fn_c_check_header_compile "$LINENO" "$ac_header" "$as_ac_Header" "$ac_includes_default
+"
+if eval test \"x\$"$as_ac_Header"\" = x"yes"; then :
+  cat >>confdefs.h <<_ACEOF
+#define `$as_echo "HAVE_$ac_header" | $as_tr_cpp` 1
+_ACEOF
+
+fi
+
+done
+
+
 
 
 
@@ -7691,6 +7813,14 @@ $as_echo "$as_me: WARNING: unable to build w3mimgdisplay with X11 support" >&2;}
    fi
   fi
   if test x"$fb" = xyes; then
+   ac_fn_c_check_header_mongrel "$LINENO" "linux/fb.h" "ac_cv_header_linux_fb_h" "$ac_includes_default"
+if test "x$ac_cv_header_linux_fb_h" = xyes; then :
+
+else
+  as_fn_error $? "linux/fb.h not found" "$LINENO" 5
+fi
+
+
    if test x"$have_imlib2" = xyes; then
      $as_echo "#define USE_W3MIMG_FB 1" >>confdefs.h
 
@@ -8803,138 +8933,11 @@ eval ac_res=\$$as_ac_Lib
 $as_echo "$ac_res" >&6; }
 if eval test \"x\$"$as_ac_Lib"\" = x"yes"; then :
   W3M_LIBS="$W3M_LIBS -l$lib"; break
-fi
-
- done
-
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for ANSI C header files" >&5
-$as_echo_n "checking for ANSI C header files... " >&6; }
-if ${ac_cv_header_stdc+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
-/* end confdefs.h.  */
-#include <stdlib.h>
-#include <stdarg.h>
-#include <string.h>
-#include <float.h>
-
-int
-main ()
-{
-
-  ;
-  return 0;
-}
-_ACEOF
-if ac_fn_c_try_compile "$LINENO"; then :
-  ac_cv_header_stdc=yes
 else
-  ac_cv_header_stdc=no
-fi
-rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
-
-if test $ac_cv_header_stdc = yes; then
-  # SunOS 4.x string.h does not declare mem*, contrary to ANSI.
-  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
-/* end confdefs.h.  */
-#include <string.h>
-
-_ACEOF
-if (eval "$ac_cpp conftest.$ac_ext") 2>&5 |
-  $EGREP "memchr" >/dev/null 2>&1; then :
-
-else
-  ac_cv_header_stdc=no
+  test "$lib" = curses && as_fn_error $? "No terminal library found" "$LINENO" 5
 fi
-rm -f conftest*
-
-fi
-
-if test $ac_cv_header_stdc = yes; then
-  # ISC 2.0.2 stdlib.h does not declare free, contrary to ANSI.
-  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
-/* end confdefs.h.  */
-#include <stdlib.h>
-
-_ACEOF
-if (eval "$ac_cpp conftest.$ac_ext") 2>&5 |
-  $EGREP "free" >/dev/null 2>&1; then :
-
-else
-  ac_cv_header_stdc=no
-fi
-rm -f conftest*
-
-fi
-
-if test $ac_cv_header_stdc = yes; then
-  # /bin/cc in Irix-4.0.5 gets non-ANSI ctype macros unless using -ansi.
-  if test "$cross_compiling" = yes; then :
-  :
-else
-  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
-/* end confdefs.h.  */
-#include <ctype.h>
-#include <stdlib.h>
-#if ((' ' & 0x0FF) == 0x020)
-# define ISLOWER(c) ('a' <= (c) && (c) <= 'z')
-# define TOUPPER(c) (ISLOWER(c) ? 'A' + ((c) - 'a') : (c))
-#else
-# define ISLOWER(c) \
-		   (('a' <= (c) && (c) <= 'i') \
-		     || ('j' <= (c) && (c) <= 'r') \
-		     || ('s' <= (c) && (c) <= 'z'))
-# define TOUPPER(c) (ISLOWER(c) ? ((c) | 0x40) : (c))
-#endif
-
-#define XOR(e, f) (((e) && !(f)) || (!(e) && (f)))
-int
-main ()
-{
-  int i;
-  for (i = 0; i < 256; i++)
-    if (XOR (islower (i), ISLOWER (i))
-	|| toupper (i) != TOUPPER (i))
-      return 2;
-  return 0;
-}
-_ACEOF
-if ac_fn_c_try_run "$LINENO"; then :
-
-else
-  ac_cv_header_stdc=no
-fi
-rm -f core *.core core.conftest.* gmon.out bb.out conftest$ac_exeext \
-  conftest.$ac_objext conftest.beam conftest.$ac_ext
-fi
-
-fi
-fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_header_stdc" >&5
-$as_echo "$ac_cv_header_stdc" >&6; }
-if test $ac_cv_header_stdc = yes; then
-
-$as_echo "#define STDC_HEADERS 1" >>confdefs.h
-
-fi
-
-# On IRIX 5.3, sys/types and inttypes.h are conflicting.
-for ac_header in sys/types.h sys/stat.h stdlib.h string.h memory.h strings.h \
-		  inttypes.h stdint.h unistd.h
-do :
-  as_ac_Header=`$as_echo "ac_cv_header_$ac_header" | $as_tr_sh`
-ac_fn_c_check_header_compile "$LINENO" "$ac_header" "$as_ac_Header" "$ac_includes_default
-"
-if eval test \"x\$"$as_ac_Header"\" = x"yes"; then :
-  cat >>confdefs.h <<_ACEOF
-#define `$as_echo "HAVE_$ac_header" | $as_tr_cpp` 1
-_ACEOF
-
-fi
-
-done
 
+ done
 
 { $as_echo "$as_me:${as_lineno-$LINENO}: checking GC library exists" >&5
 $as_echo_n "checking GC library exists... " >&6; }

configure.ac

@@ -25,7 +25,8 @@ AC_PROG_INSTALL
 AC_PROG_LN_S
 AC_PROG_MAKE_SET
 AC_PROG_RANLIB
-AC_PATH_PROGS(PERL, perl, /usr/local/bin/perl)
+AC_CHECK_PROG(PERL,[perl],[$(command -v perl)],[no])
+test "$PERL" == "no" && AC_MSG_ERROR([Required program 'perl' not found.])
 AC_PATH_PROGS(NKF, nkf, /usr/local/bin/nkf)
 AC_PATH_PROGS(MAN, man, /usr/bin/man)
 AC_PATH_XTRA