Check if libxml provides HTML parser which subparse needs.

Original commit message from CVS:
Patch by: Daniel Díaz  <yosoy@danieldiaz.org>
* configure.ac:
* gst/Makefile.am:
Check if libxml provides HTML parser which subparse needs.
Fixes #451970.

ChangeLog

+2007-08-30  Stefan Kost  <ensonic@users.sf.net>
+
+	Patch by: Daniel Díaz  <yosoy@danieldiaz.org>
+
+	* configure.ac:
+	* gst/Makefile.am:
+	  Check if libxml provides HTML parser which subparse needs.
+	  Fixes #451970.
+
 2007-08-29  Tim-Philipp Müller  <tim at centricular dot net>
 
 	* ext/alsa/gstalsa.c:

configure.ac

@@ -200,6 +200,21 @@ dnl used in gst/subparse/gstsubparse.c
 AC_CHECK_HEADERS([regex.h], HAVE_REGEX_H="yes", HAVE_REGEX_H="no")
 AM_CONDITIONAL(HAVE_REGEX_H, test "x$HAVE_REGEX_H" = "xyes")
 
+if test "x$HAVE_REGEX_H" = "xyes"; then
+  ac_cppflags_save="$CPPFLAGS"
+  CPPFLAGS="-Wall -Werror `$PKG_CONFIG --cflags libxml-2.0`"
+  AC_COMPILE_IFELSE(
+    AC_LANG_PROGRAM([
+#include <libxml/HTMLparser.h>
+                     ],[
+#ifndef LIBXML_HTML_ENABLED
+#error libxml2 has no HTML support
+#endif /* LIBXML_HTML_ENABLED */
+                     ]), HAVE_LIBXML_HTML=yes, HAVE_LIBXML_HTML=no)
+  AM_CONDITIONAL(HAVE_LIBXML_HTML, test "x$HAVE_LIBXML_HTML" = "xyes")
+  CPPFLAGS="$ac_cppflags_save"
+fi
+
 dnl used in gst/tcp
 AC_CHECK_HEADERS([sys/socket.h], 
   HAVE_SYS_SOCKET_H="yes", HAVE_SYS_SOCKET_H="no")

gst/Makefile.am

 if HAVE_REGEX_H
+if HAVE_LIBXML_HTML
 SUBPARSE = subparse
 else
 SUBPARSE =
 endif
+else
+SUBPARSE =
+endif
 
 if HAVE_SYS_SOCKET_H
 TCP = tcp
@@ -12,3 +16,4 @@ endif
 
 SUBDIRS = $(GST_PLUGINS_SELECTED) $(SUBPARSE) $(TCP)
 DIST_SUBDIRS = $(GST_PLUGINS_ALL) subparse tcp
+