* Graphviz updated to 2.20.2. Now built with fontconfig, gd and pango

support.
* New function makeFontsConf to generate a fontconfig configuration
  file.  Moved from NixOS.
* dot2pdf: use makeFontsConf to generate a fonts.conf containing just
  the Ghostscript fonts (see NIXPKGS-29).
* dot2pdf: generate PDF directly, don't go through PS.  Note that this
  and using fontconfig changes the interpretation of "fontname"
  attributes in dot graphs.

svn path=/nixpkgs/trunk/; revision=12251

pkgs/development/libraries/fontconfig/make-fonts-conf.nix

@@ -0,0 +1,13 @@
+{runCommand, libxslt, fontconfig, fontDirectories}:
+
+runCommand "fonts.conf"
+  { 
+    buildInputs = [libxslt];
+    inherit fontDirectories;
+  }
+  ''
+    xsltproc --stringparam fontDirectories "$fontDirectories" \
+      --stringparam fontconfig "${fontconfig}" \
+      ${./make-fonts-conf.xsl} ${fontconfig}/etc/fonts/fonts.conf \
+      > $out
+  ''

pkgs/development/libraries/fontconfig/make-fonts-conf.xsl

@@ -0,0 +1,40 @@
+<?xml version="1.0"?>
+
+<!--
+  This script copies the original fonts.conf from the fontconfig
+  distribution, but replaces all <dir> entries with the directories
+  specified in the $fontDirectories parameter.
+-->
+
+<xsl:stylesheet version="1.0"
+                xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
+                xmlns:str="http://exslt.org/strings"
+                extension-element-prefixes="str"
+                >
+
+  <xsl:output method='xml' encoding="UTF-8" doctype-system="fonts.dtd" />
+
+  <xsl:param name="fontDirectories" />
+  <xsl:param name="fontconfig" />
+
+  <xsl:template match="/fontconfig">
+
+    <fontconfig>
+      <xsl:copy-of select="child::node()[name() != 'dir' and name() != 'cachedir' and name() != 'include']" />
+
+      <include xml:space="preserve"><xsl:value-of select="$fontconfig" />/etc/fonts/conf.d</include>
+      <include ignore_missing="yes" xml:space="preserve">/etc/fonts/conf.d</include>
+      
+      <cachedir xml:space="preserve">/var/cache/fontconfig</cachedir>
+      <cachedir xml:space="preserve">~/.fontconfig</cachedir>
+      
+      <xsl:for-each select="str:tokenize($fontDirectories)">
+        <dir><xsl:value-of select="." /></dir>
+        <xsl:text>&#0010;</xsl:text>
+      </xsl:for-each>
+      
+    </fontconfig>
+
+  </xsl:template>
+  
+</xsl:stylesheet>