in configure.ac, per Mike Frysinger's patch, add support for

--enable-utf8 and --disable-utf8 options, with slang support and a few
other tweaks added by me


git-svn-id: svn://svn.savannah.gnu.org/nano/trunk/nano@2426 35c25a1d-7b9e-4130-9fde-d3aeb78583b8

ChangeLog

@@ -54,6 +54,13 @@ CVS code -
   help_line_len()
 	- Make the text display more flexible, and closer to what nano
 	  1.2.x does. (DLR)
+- configure.ac:
+	- Allow more flexible handling of UTF-8 support by allowing
+	  the --enable-utf8 and --disable-utf8 options. (Mike
+	  Frysinger)  DLR: Extend these options to work with slang as
+	  well as curses, consolidate the warning and error messages
+	  dealing with UTF-8 support as much as possible, and add a few
+	  minor consistency fixes.
 
 GNU nano 1.3.6 - 2005.03.20
 - General:

configure.ac

@@ -69,7 +69,7 @@ AC_ARG_ENABLE(debug,
     debug_support=yes
 fi])
 
-if test "$debug_support" != "yes"; then
+if test x$debug_support != xyes; then
     AC_DEFINE(NDEBUG, 1, [Shut up the assert warnings :-)])
 fi
 
@@ -187,6 +187,17 @@ AC_ARG_ENABLE(all,
     ])
 fi])
 
+AC_MSG_CHECKING([whether to enable UTF-8 support])
+AC_ARG_ENABLE(utf8,
+[  --enable-utf8           Enable UTF-8 support],
+[if test x$enableval = xyes; then
+    enable_utf8=yes
+else
+    enable_utf8=no
+fi],
+[enable_utf8=auto])
+AC_MSG_RESULT($enable_utf8)
+
 AC_MSG_CHECKING([whether to use slang])
 CURSES_LIB_NAME=""
 AC_ARG_WITH(slang,
@@ -198,12 +209,14 @@ AC_ARG_WITH(slang,
     *)
 	AC_MSG_RESULT(yes)
 
-	if test "$with_slang" != "yes"; then
+	if test x$with_slang != xyes; then
 	    # Add additional search path
 	    LDFLAGS="-L$with_slang/lib $LDFLAGS"
 	    CPPFLAGS="-I$with_slang/include $CPPFLAGS"
 	fi
 
+	if test x$enable_utf8 != xno
+	then
 	    AC_CHECK_HEADER(slcurses.h,
 		AC_MSG_CHECKING([for SLutf8_enable in -lslang])
 		_libs=$LIBS
@@ -219,25 +232,7 @@ int main(void)
 		    AC_DEFINE(USE_SLANG, 1, [Define to use the slang wrappers for curses instead of native curses.])
 		    slang_support=yes
 		    CURSES_LIB_WIDE=yes
-		if test "$with_slang" != "yes"; then
+		    if test x$with_slang != xyes; then
-		    CURSES_LIB="-L${with_slang}/lib -lslang"
-		else
-		    CURSES_LIB="-lslang"
-		fi
-		CURSES_LIB_NAME=slang],
-		[AC_MSG_RESULT(no)
-		AC_MSG_CHECKING([for SLtt_initialize in -lslang])
-		AC_TRY_RUN([
-#include <slcurses.h>
-int main(void)
-{
-    SLtt_initialize(NULL);
-    return 0;
-}],
-		[AC_MSG_RESULT(yes)
-		AC_DEFINE(USE_SLANG, 1, [Define to use the slang wrappers for curses instead of native curses.])
-		slang_support=yes
-		if test "$with_slang" != "yes"; then
 			CURSES_LIB="-L${with_slang}/lib -lslang"
 		    else
 			CURSES_LIB="-lslang"
@@ -264,25 +259,7 @@ int main(void)
 			AC_DEFINE(USE_SLANG, 1, [Define to use the slang wrappers for curses instead of native curses.])
 			slang_support=yes
 			CURSES_LIB_WIDE=yes
-		    if test "$with_slang" != "yes"; then
+			if test x$with_slang != xyes; then
-			CURSES_LIB="-L${with_slang}/lib -lslang $tcap"
-		    else
-			CURSES_LIB="-lslang $tcap"
-		    fi
-		    CURSES_LIB_NAME=slang],
-		    [AC_MSG_RESULT(no)
-		    AC_MSG_CHECKING([for SLtt_initialize in -lslang $tcap])
-		    AC_TRY_RUN([
-#include <slcurses.h>
-int main(void)
-{
-    SLtt_initialize(NULL);
-    return 0;
-}],
-		    [AC_MSG_RESULT(yes)
-		    AC_DEFINE(USE_SLANG, 1, [Define to use the slang wrappers for curses instead of native curses.])
-		    slang_support=yes
-		    if test "$with_slang" != "yes"; then
 			    CURSES_LIB="-L${with_slang}/lib -lslang $tcap"
 			else
 			    CURSES_LIB="-lslang $tcap"
@@ -304,13 +281,30 @@ int main(void)
 			    AC_DEFINE(USE_SLANG, 1, [Define to use the slang wrappers for curses instead of native curses.])
 			    slang_support=yes
 			    CURSES_LIB_WIDE=yes
-			if test "$with_slang" != "yes"; then
+			    if test x$with_slang != xyes; then
 				CURSES_LIB="-L${with_slang}/lib -lslang $tcap -lm"
 			    else
 				CURSES_LIB="-lslang $tcap -lm"
 			    fi
 			    CURSES_LIB_NAME=slang],
-			AC_MSG_CHECKING([for SLtt_initialize in -lslang $tcap -lm])
+			    [AC_MSG_RESULT(no)],
+    AC_MSG_WARN([*** Can not use slang when cross-compiling]))],
+    AC_MSG_WARN([*** Can not use slang when cross-compiling]))],
+    AC_MSG_WARN([*** Can not use slang when cross-compiling])),
+	    AC_MSG_ERROR([
+*** The header file slcurses.h was not found. If you wish to use
+*** slang support this header file is required. Please either
+*** install a version of slang that includes the slcurses.h file or
+*** do not call the configure script with --with-slang
+	    ]))
+	fi
+
+	if eval "test x$CURSES_LIB_NAME = x"
+	then
+	    AC_CHECK_HEADER(slcurses.h,
+		AC_MSG_CHECKING([for SLtt_initialize in -lslang])
+		_libs=$LIBS
+		LIBS="$LIBS -lslang"
 		AC_TRY_RUN([
 #include <slcurses.h>
 int main(void)
@@ -321,7 +315,54 @@ int main(void)
 		    [AC_MSG_RESULT(yes)
 		    AC_DEFINE(USE_SLANG, 1, [Define to use the slang wrappers for curses instead of native curses.])
 		    slang_support=yes
-			if test "$with_slang" != "yes"; then
+		    if test x$with_slang != xyes; then
+			CURSES_LIB="-L${with_slang}/lib -lslang"
+		    else
+			CURSES_LIB="-lslang"
+		    fi
+		    CURSES_LIB_NAME=slang],
+		    [AC_MSG_RESULT(no)
+
+		    # We might need the term library
+		    for termlib in ncurses curses termcap terminfo termlib; do
+			AC_CHECK_LIB([${termlib}], tputs, [tcap="-l$termlib"])
+			test -n "$tcap" && break
+		    done
+
+		    AC_MSG_CHECKING([for SLtt_initialize in -lslang $tcap])
+		    LIBS="$LIBS $tcap"
+		    AC_TRY_RUN([
+#include <slcurses.h>
+int main(void)
+{
+    SLtt_initialize(NULL);
+    return 0;
+}],
+			[AC_MSG_RESULT(yes)
+			AC_DEFINE(USE_SLANG, 1, [Define to use the slang wrappers for curses instead of native curses.])
+			slang_support=yes
+			if test x$with_slang != xyes; then
+			    CURSES_LIB="-L${with_slang}/lib -lslang $tcap"
+			else
+			    CURSES_LIB="-lslang $tcap"
+			fi
+			CURSES_LIB_NAME=slang],
+			[AC_MSG_RESULT(no)
+
+			# We might need the math library
+			AC_MSG_CHECKING([for SLtt_initialize in -lslang $tcap -lm])
+			LIBS="$LIBS -lm"
+			AC_TRY_RUN([
+#include <slcurses.h>
+int main(void)
+{
+    SLtt_initialize(NULL);
+    return 0;
+}],
+			    [AC_MSG_RESULT(yes)
+			    AC_DEFINE(USE_SLANG, 1, [Define to use the slang wrappers for curses instead of native curses.])
+			    slang_support=yes
+			    if test x$with_slang != xyes; then
 				CURSES_LIB="-L${with_slang}/lib -lslang $tcap -lm"
 			    else
 				CURSES_LIB="-lslang $tcap -lm"
@@ -330,9 +371,6 @@ int main(void)
 			    [AC_MSG_RESULT(no)],
     AC_MSG_WARN([*** Can not use slang when cross-compiling]))],
     AC_MSG_WARN([*** Can not use slang when cross-compiling]))],
-AC_MSG_WARN([*** Can not use slang when cross-compiling]))],
-AC_MSG_WARN([*** Can not use slang when cross-compiling]))],
-AC_MSG_WARN([*** Can not use slang when cross-compiling])),
     AC_MSG_WARN([*** Can not use slang when cross-compiling])),
 	    AC_MSG_ERROR([
 *** The header file slcurses.h was not found. If you wish to use
@@ -340,18 +378,25 @@ AC_MSG_WARN([*** Can not use slang when cross-compiling])),
 *** install a version of slang that includes the slcurses.h file or
 *** do not call the configure script with --with-slang
 	    ]))
+	fi
 
-	test "${_libs+set}" = "set" && LIBS=$_libs
+	test ${_libs+set} = set && LIBS=$_libs
 
-	if test "$with_slang" != "yes"; then
+	if test x$with_slang != xyes; then
 	    LDFLAGS=${_ldflags}
 	fi
 	;;
     esac], [AC_MSG_RESULT(no)])
 
 dnl Checks for functions
-AC_CHECK_FUNCS(snprintf vsnprintf isblank iswalnum iswblank iswspace strcasecmp strncasecmp strcasestr strnlen getline getdelim mblen mbtowc wctomb wcwidth)
+AC_CHECK_FUNCS(snprintf vsnprintf isblank strcasecmp strncasecmp strcasestr strnlen getline getdelim)
-if test "x$ac_cv_func_snprintf" = "xno" -o "x$ac_cv_func_vsnprintf" = "xno"
+
+if test x$enable_utf8 != xno
+then
+    AC_CHECK_FUNCS(iswalnum mblen mbtowc wctomb wcwidth iswspace iswblank)
+fi
+
+if test x$ac_cv_func_snprintf = xno -o x$ac_cv_func_vsnprintf = xno
 then
 	AM_PATH_GLIB_2_0(2.0.0,,
 	    AC_MSG_ERROR([
@@ -372,7 +417,12 @@ dnl Checks for libraries.
 if eval "test x$CURSES_LIB_NAME = x"
 then
     AC_CHECK_HEADERS(ncurses.h)
-    AC_CHECK_LIB(ncursesw, wget_wch, [CURSES_LIB="-lncursesw" CURSES_LIB_NAME=ncursesw CURSES_LIB_WIDE="yes"])
+
+    if test x$enable_utf8 != xno
+    then
+	AC_CHECK_LIB(ncursesw, wget_wch, [CURSES_LIB="-lncursesw" CURSES_LIB_NAME=ncursesw CURSES_LIB_WIDE=yes])
+    fi
+
     if eval "test x$CURSES_LIB_NAME = x"
     then
 	AC_CHECK_LIB(ncurses, initscr, [CURSES_LIB="-lncurses" CURSES_LIB_NAME=ncurses])
@@ -382,7 +432,12 @@ fi
 if eval "test x$CURSES_LIB_NAME = x"
 then
     AC_CHECK_HEADERS(curses.h)
-    AC_CHECK_LIB(curses, wget_wch, [CURSES_LIB="-lcurses" CURSES_LIB_NAME=curses CURSES_LIB_WIDE="yes"])
+
+    if test x$enable_utf8 != xno
+    then
+	AC_CHECK_LIB(curses, wget_wch, [CURSES_LIB="-lcurses" CURSES_LIB_NAME=curses CURSES_LIB_WIDE=yes])
+    fi
+
     if eval "test x$CURSES_LIB_NAME = x"
     then
 	 AC_CHECK_LIB(curses, initscr, [CURSES_LIB="-lcurses" CURSES_LIB_NAME=curses])
@@ -416,11 +471,34 @@ then
 	LDFLAGS="$LDFLAGS $GLIB_LIBS"
 fi
 
-if test "x$CURSES_LIB_WIDE" = "xyes" -a "x$ac_cv_func_iswalnum" = "xyes" -a "x$ac_cv_func_mblen" = "xyes" -a "x$ac_cv_func_mbtowc" = "xyes" -a "x$ac_cv_func_wctomb" = "xyes" -a "x$ac_cv_func_wcwidth" = "xyes" && test "x$ac_cv_func_iswspace" = "xyes" -o "x$ac_cv_func_iswblank" = "xyes"
+if test x$enable_utf8 != xno && \
+   test x$CURSES_LIB_WIDE = xyes -a \
+        x$ac_cv_func_iswalnum = xyes -a \
+        x$ac_cv_func_mblen = xyes -a \
+        x$ac_cv_func_mbtowc = xyes -a \
+        x$ac_cv_func_wctomb = xyes -a \
+        x$ac_cv_func_wcwidth = xyes && \
+   test x$ac_cv_func_iswspace = xyes -o x$ac_cv_func_iswblank = xyes
 then
 	AC_DEFINE(NANO_WIDE, 1, [Define this if your system has sufficient wide character support (a wide curses library, iswalnum(), iswspace() or iswblank(), mblen(), mbtowc(), wctomb(), and wcwidth()).])
 else
-	AC_MSG_WARN([Insufficient wide character support found.  nano will not be able to support UTF-8.])
+    if test x$enable_utf8 = xyes
+    then
+	AC_MSG_ERROR([
+*** UTF-8 support was requested, but insufficient UTF-8 support was
+*** detected in your curses and/or C libraries.  Please verify that your
+*** slang was built with UTF-8 support or your curses was built with
+*** wide character support, and that your C library was built with wide
+*** character support.])
+    elif test x$enable_utf8 != xno
+    then
+	AC_MSG_WARN([
+*** Insufficient UTF-8 support was detected in your curses and/or C
+*** libraries.  If you want UTF-8 support, please verify that your slang
+*** was built with UTF-8 support or your curses was built with wide
+*** character support, and that your C library was built with wide
+*** character support.])
+    fi
 fi
 
 AC_CONFIG_FILES([