Add generation of a few files in phase 1 that will help speed up phase 2

Makefile

@@ -1,9 +1,10 @@
 # -----------------------------------------------------------------------------
-# Makefile for "premake" step
+# Makefile for FSFE website build, phase 1
 # -----------------------------------------------------------------------------
-# This Makefile creates some .xml and xhtml files which serve as source files
-# in the main build run. It is executed in the source directory, before the
-# Makefile for the main build run is constructed and executed.
+# This Makefile is executed in the root of the source directory tree, and
+# creates some .xml and xhtml files as well as some symlinks, all of which
+# serve as input files in phase 2. The whole phase 1 runs within the source
+# directory tree and does not touch the target directory tree at all.
 # -----------------------------------------------------------------------------
 
 .PHONY: all .FORCE
@@ -50,15 +51,83 @@ d_month.en.xml: $(if $(findstring $(MONTH),$(shell cat d_month.en.xml)),,.FORCE)
 d_year.en.xml: $(if $(findstring  $(YEAR),$(shell cat d_year.en.xml)),,.FORCE)
 	printf %s\\n  '$(YEAR)' >$@
 
+# -----------------------------------------------------------------------------
+# Create XML symlinks
+# -----------------------------------------------------------------------------
+
+# After this step, the following symlinks will exist:
+# * tools/.texts-<lang>.xml for each language
+# * ./fundraising.<lang>.xml for each language
+# Each of these symlinks will point to the corresponding file without a dot at
+# the beginning of the filename, if present, and to the English version
+# otherwise. This symlinks make sure that phase 2 can easily use the right file
+# for each language, also as a prerequisite in the Makefile.
+
+LANGUAGES := $(shell . build/languages.sh && get_languages)
+
+TEXTS_LINKS := $(foreach lang,$(LANGUAGES),tools/.texts-$(lang).xml)
+
+all: $(TEXTS_LINKS)
+tools/.texts-%.xml: .FORCE
+	@if [ -f tools/texts-$*.xml ]; then \
+	  ln -sf texts-$*.xml $@; \
+	else \
+	  ln -sf texts-en.xml $@; \
+	fi
+
+FUNDRAISING_LINKS := $(foreach lang,$(LANGUAGES),.fundraising.$(lang).xml)
+
+all: $(FUNDRAISING_LINKS)
+.fundraising.%.xml: .FORCE
+	@if [ -f fundraising.$*.xml ]; then \
+	  ln -sf fundraising.$*.xml $@; \
+	else \
+	  ln -sf fundraising.en.xml $@; \
+	fi
+
+# -----------------------------------------------------------------------------
+# Create XSL symlinks
+# -----------------------------------------------------------------------------
+
+# After this step, each directory with source files for HTML pages contains a
+# symlink named .default.xsl and pointing to the default.xsl "responsible" for
+# this directory. These symlinks make it easier for the phase 2 Makefile to
+# determine which XSL script should be used to build a HTML page from a source
+# file.
+
+# All directories containing source files for HTML pages.
+XHTML_DIRS := $(patsubst %/,%,$(sort $(dir $(shell find -name '*.??.xhtml'))))
+
+.PHONY: default_xsl
+all: default_xsl
+default_xsl:
+	@for directory in $(XHTML_DIRS); do \
+	  dir="$${directory}"; \
+	  prefix=""; \
+	  until [ -f "$${dir}/default.xsl" -o "$${dir}" = "." ]; do \
+	    dir="$${dir%/*}"; \
+	    prefix="$${prefix}../"; \
+	  done; \
+	  ln -sf "$${prefix}default.xsl" "$${directory}/.default.xsl"; \
+	done
+
 # -----------------------------------------------------------------------------
 # Generate XML filelists
 # -----------------------------------------------------------------------------
 
-# Generation of XML filelists is handled in an external script which generates
-# all .xmllist and the tags/tagged-*.en.xhtml files. These files cannot be
-# targets in this Makefile, because the list of tags is not known when the
-# Makefile starts - some new tags might be created when generating the .xml
-# files in the news/* subdirectories.
+# After this step, the following files will be up to date:
+# * tags/tagged-<tags>.en.xhtml for each tag used. Apart from being
+#   automatically created, these are regular source files for HTML pages, and
+#   in phase 2 are built into pages listing all news items and events for a
+#   tag.
+# * <dir>/.<base>.xmllist for each <dir>/<base>.sources as well as for each
+#   tags/tagged-<tags>.en.xhtml. These files are used in phase 2 to include the
+#   correct XML files when generating the HTML pages. It is taken care that
+#   these files are only updated whenever their content actually changes, so
+#   they can serve as a prerequisite in the phase 2 Makefile.
+# This step is handled in an external script, because the list of files to
+# generate is not known when the Makefile starts - some new tags might be
+# introduced when generating the .xml files in the news/* subdirectories.
 
 .PHONY: xmllists
 all: xmllists