Add fontconfig as dependency

pangocairo does not list fontconfig as a dependency.

configure.ac

@@ -1103,6 +1103,26 @@ fi
 VIPS_CFLAGS="$VIPS_CFLAGS $PANGOCAIRO_CFLAGS"
 VIPS_LIBS="$VIPS_LIBS $PANGOCAIRO_LIBS"
 
+# font file support with fontconfig
+AC_ARG_WITH([fontconfig], 
+  AS_HELP_STRING([--without-fontconfig], 
+    [build without fontconfig (default: test)]))
+
+if test x"$with_pangocairo" != x"no" -a x"$with_fontconfig" != x"no"; then
+  PKG_CHECK_MODULES(FONTCONFIG, fontconfig,
+    [AC_DEFINE(HAVE_FONTCONFIG,1,[define if you have fontconfig installed.])
+     with_fontconfig=yes
+     PACKAGES_USED="$PACKAGES_USED fontconfig"
+    ],
+    [AC_MSG_WARN([fontconfig not found; disabling fontconfig support])
+     with_fontconfig=no
+    ]
+  )
+fi
+
+VIPS_CFLAGS="$VIPS_CFLAGS $FONTCONFIG_CFLAGS"
+VIPS_LIBS="$VIPS_LIBS $FONTCONFIG_LIBS"
+
 # look for TIFF with pkg-config ... fall back to our tester
 # pkgconfig support for libtiff starts with libtiff-4
 AC_ARG_WITH([tiff], 
@@ -1326,6 +1346,7 @@ accelerate loops with orc: $with_orc, \
 ICC profile support with lcms: $with_lcms, \
 zlib: $with_zlib, \
 text rendering with pangocairo: $with_pangocairo, \
+font file support with fontconfig: $with_fontconfig, \
 EXIF metadata support with libexif: $with_libexif, \
 JPEG load/save with libjpeg: $with_jpeg, \
 PNG load with libspng: $with_libspng, \
@@ -1428,6 +1449,7 @@ accelerate loops with orc:              $with_orc
 ICC profile support with lcms:          $with_lcms
 zlib:                                   $with_zlib
 text rendering with pangocairo:         $with_pangocairo
+font file support with fontconfig:      $with_fontconfig
 EXIF metadata support with libexif:     $with_libexif
 
 ## File format support

libvips/create/text.c

@@ -84,7 +84,10 @@
 #include <cairo.h>
 #include <pango/pango.h>
 #include <pango/pangocairo.h>
+
+#ifdef HAVE_FONTCONFIG
 #include <fontconfig/fontconfig.h>
+#endif
 
 #include "pcreate.h"
 
@@ -123,10 +126,12 @@ static GMutex *vips_text_lock = NULL;
  */
 static PangoFontMap *vips_text_fontmap = NULL;
 
+#ifdef HAVE_FONTCONFIG
 /* All the fontfiles we've loaded. fontconfig lets you add a fontfile
  * repeatedly, and we obviously don't want that.
  */
 static GHashTable *vips_text_fontfiles = NULL;
+#endif
 
 static void
 vips_text_dispose( GObject *gobject )
@@ -365,13 +370,17 @@ vips_text_build( VipsObject *object )
 
 	if( !vips_text_fontmap )
 		vips_text_fontmap = pango_cairo_font_map_new();
+
+#ifdef HAVE_FONTCONFIG
 	if( !vips_text_fontfiles )
 		vips_text_fontfiles = 
 			g_hash_table_new( g_str_hash, g_str_equal );
+#endif
 
 	text->context = pango_font_map_create_context( 
 		PANGO_FONT_MAP( vips_text_fontmap ) );
 
+#ifdef HAVE_FONTCONFIG
 	if( text->fontfile &&
 		!g_hash_table_lookup( vips_text_fontfiles, text->fontfile ) ) {
 		if( !FcConfigAppFontAddFile( NULL, 
@@ -386,6 +395,11 @@ vips_text_build( VipsObject *object )
 			text->fontfile,
 			g_strdup( text->fontfile ) );
 	}
+#else
+	if( text->fontfile )
+		g_warning( "%s",
+			_( "ignoring fontfile (no fontconfig support)" ) );
+#endif
 
 	/* If our caller set height and not dpi, we adjust dpi until 
 	 * we get a fit.