Created configuration file for QWT library. This is in lieu of hand installing

a .pc file per the gr-qtgui README.  Component gr-qtgui is still disabled in 
configure.ac until testing is complete.  Requires qwt files to be included using
the #include <qwt/...> syntax; this is the default for binary installations of
the qwt library. Normal users will user run ./configure without any changes.


git-svn-id: http://gnuradio.org/svn/gnuradio/trunk@4745 221aa14e-8319-0410-a670-987f0aec2ac5

1 files changed, 99 insertions, 0 deletions

diff --git a/config/gr_qwt.m4 b/config/gr_qwt.m4
new file mode 100644
index 000000000..3481873b7
--- /dev/null
+++ b/config/gr_qwt.m4
@@ -0,0 +1,99 @@
+dnl
+dnl Copyright 2007 Free Software Foundation, Inc.
+dnl 
+dnl This file is part of GNU Radio
+dnl 
+dnl GNU Radio is free software; you can redistribute it and/or modify
+dnl it under the terms of the GNU General Public License as published by
+dnl the Free Software Foundation; either version 2, or (at your option)
+dnl any later version.
+dnl 
+dnl GNU Radio is distributed in the hope that it will be useful,
+dnl but WITHOUT ANY WARRANTY; without even the implied warranty of
+dnl MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+dnl GNU General Public License for more details.
+dnl 
+dnl You should have received a copy of the GNU General Public License
+dnl along with GNU Radio; see the file COPYING.  If not, write to
+dnl the Free Software Foundation, Inc., 51 Franklin Street,
+dnl Boston, MA 02110-1301, USA.
+dnl
+
+dnl Configure paths for library qwt.
+dnl
+dnl GR_PATH_QWT([ACTION-IF-FOUND [, ACTION-IF-NOT-FOUND]])
+dnl
+dnl Test for library qwt, set QWT_CFLAGS and QWT_LIBS if found. Assumes 
+dnl QT_CFLAGS and QT_LIBS have already been correctly set.
+dnl
+
+AC_DEFUN([GR_QWT],
+[
+    dnl Save the environment
+    AC_LANG_PUSH(C++)
+    qwt_save_CPPFLAGS="$CPPFLAGS"
+    qwt_save_LIBS="$LIBS"
+    libqwt_ok=yes
+
+    dnl Allow user to specify where QWT files are
+    AC_ARG_WITH([qwt-libdir],
+		[  --with-qwt-libdir=path  Prefix where QWT library is installed (optional)],
+		[qwt_libdir="$withval"], [qwt_libdir=""])
+
+    AC_ARG_WITH([qwt-incdir],
+		[  --with-qwt-incdir=path  Prefix where QWT include files are (optional)],
+		[qwt_incdir="$withval"], [qwt_incdir=""])
+
+    dnl Create QWT_CFLAGS based on user input
+    AC_MSG_CHECKING(QWT_CFLAGS)
+    if test "$qwt_incdir" != "" ; then
+	QWT_CFLAGS="$QWT_CFLAGS -I$qwt_incdir"
+    fi
+    AC_MSG_RESULT($QWT_CFLAGS)
+    
+    dnl Set CPPFLAGS so C++ tests can operate
+    CPPFLAGS="$CPPFLAGS $QT_CFLAGS $QWT_CFLAGS"
+
+    dnl Check for presence of header files
+    AC_CHECK_HEADERS([qwt/qwt.h], 
+		     [],
+		     [libqwt_ok=no;AC_MSG_RESULT([cannot find usable qwt headers])]
+    )
+
+    dnl Set QWT_LIBS based on user input
+    AC_MSG_CHECKING(QWT_LIBS)
+    QWT_LIBS="-lqwt"
+    if test "$qwt_libdir" != "" ; then
+	QWT_LIBS="$QWT_LIBS -L$qwt_libdir"
+    fi
+    AC_MSG_RESULT($QWT_LIBS)
+
+    dnl Set LIBS so C++ link test can operate
+    LIBS="$QWT_LIBS $QT_LIBS $LIBS"
+
+    dnl Check that library files can be linked in
+    dnl This references an arbitrary static class method 
+    AC_TRY_LINK([#include <qwt/qwt_text.h>],
+		[Qt::TextFormat tf = QwtText::defaultFormat()],
+		[],
+                [libqwt_ok=no]
+    )
+
+    dnl Restore saved variables
+    LIBS="$qwt_save_LIBS"
+    CPPFLAGS="$qwt_save_CPPFLAGS"
+    AC_LANG_POP
+
+    dnl Execute user actions
+    if test "x$libqwt_ok" = "xyes" ; then
+	ifelse([$1], , :, [$1])
+    else
+	QWT_CFLAGS=""
+	QWT_LIBDIRS=""
+	ifelse([$2], , :, [$2])
+    fi
+
+    dnl Export our variables
+    AC_SUBST(QWT_CFLAGS)
+    AC_SUBST(QWT_LIBS)
+])