gtk_doc: replace catalog lookup hack

In the previous commit, we added a setup hook to docbook dtd and xsl
packages, that adds derivation’s catalog file to an environment variable.
That should, in theory, remove the need for declaring their catalogs manually.
Unfortunately, xmlcatalog utility expects exactly one catalog file, completely
disregarding the environment variable in non-interactive context. In the same
spirit, the design of gtk-doc m4 files only admits a single catalog file,
resulting in another ugly hack.

pkgs/development/tools/documentation/gtk-doc/default.nix

@@ -1,4 +1,4 @@
-{ stdenv, fetchurl, pkgconfig, perl, python, libxml2Python, libxslt, which
+{ stdenv, fetchurl, autoreconfHook, pkgconfig, perl, python, libxml2Python, libxslt, which
 , docbook_xml_dtd_43, docbook_xsl, gnome_doc_utils, dblatex, gettext, itstool }:
 
 stdenv.mkDerivation rec {
@@ -10,29 +10,20 @@ stdenv.mkDerivation rec {
     sha256 = "0hpxcij9xx9ny3gs9p0iz4r8zslw8wqymbyababiyl7603a6x90y";
   };
 
+  patches = [
+    ./respect-xml-catalog-files-var.patch
+  ];
+
   outputDevdoc = "out";
 
-  # maybe there is a better way to pass the needed dtd and xsl files
+  nativeBuildInputs = [ autoreconfHook ];
-  # "-//OASIS//DTD DocBook XML V4.1.2//EN" and "http://docbook.sourceforge.net/release/xsl/current/html/chunk.xsl"
-  preConfigure = ''
-    mkdir -p $out/nix-support
-    cat > $out/nix-support/catalog.xml << EOF
-    <?xml version="1.0"?>
-    <!DOCTYPE catalog PUBLIC "-//OASIS//DTD Entity Resolution XML Catalog V1.0//EN" "http://www.oasis-open.org/committees/entity/release/1.0/catalog.dtd">
-    <catalog xmlns="urn:oasis:names:tc:entity:xmlns:xml:catalog">
-      <nextCatalog  catalog="${docbook_xsl}/xml/xsl/docbook/catalog.xml" />
-      <nextCatalog  catalog="${docbook_xml_dtd_43}/xml/dtd/docbook/catalog.xml" />
-    </catalog>
-    EOF
-
-    configureFlags="--with-xml-catalog=$out/nix-support/catalog.xml --disable-scrollkeeper";
-  '';
-
   buildInputs =
    [ pkgconfig perl python libxml2Python libxslt docbook_xml_dtd_43 docbook_xsl
      gnome_doc_utils dblatex gettext which itstool
    ];
 
+  configureFlags = "--disable-scrollkeeper";
+
   meta = with stdenv.lib; {
     homepage = https://www.gtk.org/gtk-doc;
     description = "Tools to extract documentation embedded in GTK+ and GNOME source code";

pkgs/development/tools/documentation/gtk-doc/respect-xml-catalog-files-var.patch

@@ -0,0 +1,28 @@
+diff --git a/m4/gtkdoc_jh_check_xml_catalog.m4 b/m4/gtkdoc_jh_check_xml_catalog.m4
+index 618c1c9..1842a0d 100644
+--- a/m4/gtkdoc_jh_check_xml_catalog.m4
++++ b/m4/gtkdoc_jh_check_xml_catalog.m4
+@@ -10,7 +10,21 @@ AC_DEFUN([JH_CHECK_XML_CATALOG],
+ 		AC_MSG_RESULT([found])
+ 		ifelse([$3],,,[$3])
+ 	else
+-		AC_MSG_RESULT([not found])
+-		ifelse([$4],,[AC_MSG_ERROR([could not find ifelse([$2],,[$1],[$2]) in XML catalog])],[$4])
++		jh_check_xml_catalog_saved_ifs="$IFS"
++		IFS=' '
++		for f in $XML_CATALOG_FILES; do
++			if [[ -f "$f" ]] && \
++				AC_RUN_LOG([$XMLCATALOG --noout "$f" "$1" >&2]); then
++				jh_found_xmlcatalog=true
++				AC_MSG_RESULT([found])
++				ifelse([$3],,,[$3])
++				break
++			fi
++		done
++		IFS="$jh_check_xml_catalog_saved_ifs"
++		if ! $jh_found_xmlcatalog; then
++			AC_MSG_RESULT([not found])
++			ifelse([$4],,[AC_MSG_ERROR([could not find ifelse([$2],,[$1],[$2]) in XML catalog])],[$4])
++		fi
+ 	fi
+ ])