Move XSL updates to phase 1

Makefile

@@ -113,7 +113,7 @@ default_xsl:
 	done
 
 # -----------------------------------------------------------------------------
-# Generate XML filelists
+# Update XML filelists
 # -----------------------------------------------------------------------------
 
 # After this step, the following files will be up to date:
@@ -134,3 +134,18 @@ default_xsl:
 all: xmllists
 xmllists: $(SUBDIRS)
 	@tools/make_xmllists.sh
+
+# -----------------------------------------------------------------------------
+# Update XSL stylesheets
+# -----------------------------------------------------------------------------
+
+# This step updates (actually: just touches) all XSL files which depend on
+# another XSL file that has changed since the last build run. The phase 2
+# Makefile then only has to consider the directly used stylesheet as a
+# prerequisite for building each file and doesn't have to worry about other
+# stylesheets imported into that one.
+
+.PHONY: stylesheets
+all: stylesheets
+stylesheets: $(SUBDIRS)
+	@tools/update_stylesheets.sh

build/makerules.sh

@@ -24,35 +24,6 @@ OUTPUTDIR = $output
 STATUSDIR = $statusdir
 LANGUAGES = $languages
 
-# -----------------------------------------------------------------------------
-# Touch all XSL files depending on a newer other XSL file
-# -----------------------------------------------------------------------------
-
-EOF
-
-  # Generate make dependencies for all .xsl files in input tree
-  find "${input}" -name '*.xsl' -not -name '.default.xsl' -printf '%P\n' \
-  | while read xsl_file; do
-    prerequisites=$(echo $(
-      cat "${input}/${xsl_file}" \
-      | tr '\n\t\r' '   ' \
-      | sed -r 's;(<xsl:(include|import)[^>]*>);\n\1\n;g' \
-      | sed -nr '/<xsl:(include|import)[^>]*>/s;^.*href *= *"([^"]*)".*$;\1;gp' \
-      | xargs -I'{}' realpath "${input}/$(dirname ${xsl_file})/{}" \
-      | sed -r "s;^${input};\$(INPUTDIR);"
-    ))
-    if [ -n "${prerequisites}" ]; then
-      echo "all: \$(INPUTDIR)/${xsl_file}"
-      echo "\$(INPUTDIR)/${xsl_file}: ${prerequisites}"
-      echo ""
-    fi
-  done 
-
-  cat <<EOF
-%.xsl:
-	@echo "* Touching \$*"
-	@touch \$@
-
 # -----------------------------------------------------------------------------
 # Build .html files from .xhtml sources
 # -----------------------------------------------------------------------------

tools/update_stylesheets.sh

@@ -0,0 +1,56 @@
+#!/bin/bash
+# -----------------------------------------------------------------------------
+# Update XSL stylesheets (*.xsl) according to their dependency
+# -----------------------------------------------------------------------------
+# This script is called from the phase 1 Makefile and updates (actually: just
+# touches) all XSL files which depend on another XSL file that has changed
+# since the last build run. The phase 2 Makefile then only has to consider the
+# directly used stylesheet as a prerequisite for building each file and doesn't
+# have to worry about other stylesheets imported into that one.
+# -----------------------------------------------------------------------------
+
+set -e
+set -o pipefail
+
+echo "* Updating XSL stylesheets"
+
+pid=$$
+
+# -----------------------------------------------------------------------------
+# Generate a temporary makefile with dependencies for all .xsl files
+# -----------------------------------------------------------------------------
+
+makefile="/tmp/makefile-${pid}"
+
+{
+  for xsl_file in $(find * -name '*.xsl' -not -name '.default.xsl'); do
+    prerequisites=$(echo $(
+      cat "${xsl_file}" \
+      | tr '\t\r\n' '   ' \
+      | sed -r 's/(<xsl:(include|import)[^>]*>)/\n\1\n/g' \
+      | sed -rn '/<xsl:(include|import)[^>]*>/s/^.*href *= *"([^"]*)".*$/\1/gp' \
+      | xargs -I'{}' realpath "$(dirname ${xsl_file})/{}" \
+    ))
+    if [ -n "${prerequisites}" ]; then
+      echo "all: ${xsl_file}"
+      echo "${xsl_file}: ${prerequisites}"
+      echo ""
+    fi
+  done 
+
+  echo '%.xsl:'
+  echo -e '\techo "*   Touching $*"'
+  echo -e '\ttouch $@'
+} > "${makefile}"
+
+# -----------------------------------------------------------------------------
+# Execute the temporary makefile
+# -----------------------------------------------------------------------------
+
+make --silent --file="${makefile}"
+
+# -----------------------------------------------------------------------------
+# Clean up
+# -----------------------------------------------------------------------------
+
+rm -f "${makefile}"