middleclick-autoscroll 1.0.0

Middle-click autoscroll for every Chromium-based application on the system:
Electron and CEF applications, Chromium-based browsers, Flatpaks, Spotify and
Steam, plus anything installed later.

The flag goes into an Arch wrapper's <name>-flags.conf where one exists, and
into a shadowing desktop entry where it does not. Steam gets its web helper
script patched and -noverifyfiles on its launcher, because it restores its own
files otherwise. Every change is recorded so it can be taken back exactly.

Makefile

@@ -0,0 +1,114 @@
+# middleclick-autoscroll - build and install
+#
+# Everything here is plain shell; "building" only means compiling the gettext
+# catalogs and rendering the man page. Both targets degrade to a no-op when
+# msgfmt/scdoc are missing, so the tree stays usable for development without
+# the build dependencies installed.
+
+# Overridable so a packager can pass the version it is actually building
+# (`make VERSION=$pkgver`). The literal below is the fallback for builds
+# straight from a checkout, and is what a release tag has to carry.
+VERSION      ?= 1.0.0
+
+PREFIX       ?= /usr
+DESTDIR      ?=
+BINDIR       ?= $(PREFIX)/bin
+DATADIR      ?= $(PREFIX)/share
+LIBDIR       ?= $(DATADIR)/middleclick-autoscroll/lib
+LOCALEDIR    ?= $(DATADIR)/locale
+MANDIR       ?= $(DATADIR)/man
+USERUNITDIR  ?= $(PREFIX)/lib/systemd/user
+
+LINGUAS      := de
+MOFILES      := $(patsubst %,po/%.mo,$(LINGUAS))
+MANPAGE      := doc/middleclick-autoscroll.1
+
+LIBS         := $(wildcard src/lib/*.sh)
+
+MSGFMT       := $(shell command -v msgfmt 2>/dev/null)
+SCDOC        := $(shell command -v scdoc 2>/dev/null)
+
+.PHONY: all build install uninstall check clean
+
+all: build
+
+build: $(MOFILES) $(MANPAGE)
+
+po/%.mo: po/%.po
+ifdef MSGFMT
+	$(MSGFMT) --check --output-file=$@ $<
+else
+	@echo "msgfmt not found - skipping $@"
+endif
+
+$(MANPAGE): doc/middleclick-autoscroll.1.scd
+ifdef SCDOC
+	$(SCDOC) < $< > $@
+else
+	@echo "scdoc not found - skipping $@"
+endif
+
+# Syntax-check every shell file, and run shellcheck when it is available.
+check:
+	@set -e; for f in src/middleclick-autoscroll $(LIBS); do \
+		bash -n "$$f" && echo "ok  $$f"; \
+	done
+	@if command -v shellcheck >/dev/null 2>&1; then \
+		shellcheck -x -e SC1090,SC1091 src/middleclick-autoscroll $(LIBS); \
+		echo "ok  shellcheck"; \
+	else \
+		echo "shellcheck not found - skipped"; \
+	fi
+	@if command -v desktop-file-validate >/dev/null 2>&1; then \
+		echo "ok  desktop-file-validate (nothing to check)"; \
+	fi
+
+install: build
+	# executable
+	install -Dm755 src/middleclick-autoscroll \
+		"$(DESTDIR)$(BINDIR)/middleclick-autoscroll"
+
+	# shell libraries
+	install -d "$(DESTDIR)$(LIBDIR)"
+	install -Dm644 -t "$(DESTDIR)$(LIBDIR)" $(LIBS)
+
+	# the version and the resolved paths are baked in at install time
+	sed -i -e 's|@VERSION@|$(VERSION)|g' \
+	       -e 's|@LIBDIR@|$(LIBDIR)|g' \
+	       -e 's|@LOCALEDIR@|$(LOCALEDIR)|g' \
+	       "$(DESTDIR)$(BINDIR)/middleclick-autoscroll" \
+	       "$(DESTDIR)$(LIBDIR)"/*.sh
+
+	# user units: the watcher, and the one-shot it starts
+	install -Dm644 res/systemd/middleclick-autoscroll.service \
+		"$(DESTDIR)$(USERUNITDIR)/middleclick-autoscroll.service"
+	install -Dm644 res/systemd/middleclick-autoscroll.path \
+		"$(DESTDIR)$(USERUNITDIR)/middleclick-autoscroll.path"
+	sed -i -e 's|@BINDIR@|$(BINDIR)|g' \
+		"$(DESTDIR)$(USERUNITDIR)/middleclick-autoscroll.service"
+
+	# translations
+	@for l in $(LINGUAS); do \
+		if [ -f "po/$$l.mo" ]; then \
+			install -Dm644 "po/$$l.mo" \
+				"$(DESTDIR)$(LOCALEDIR)/$$l/LC_MESSAGES/middleclick-autoscroll.mo"; \
+		fi; \
+	done
+
+	# documentation
+	@if [ -f $(MANPAGE) ]; then \
+		install -Dm644 $(MANPAGE) "$(DESTDIR)$(MANDIR)/man1/middleclick-autoscroll.1"; \
+	fi
+	install -Dm644 README.md \
+		"$(DESTDIR)$(DATADIR)/doc/middleclick-autoscroll/README.md"
+
+uninstall:
+	rm -f  "$(DESTDIR)$(BINDIR)/middleclick-autoscroll"
+	rm -rf "$(DESTDIR)$(DATADIR)/middleclick-autoscroll"
+	rm -f  "$(DESTDIR)$(USERUNITDIR)/middleclick-autoscroll.service"
+	rm -f  "$(DESTDIR)$(USERUNITDIR)/middleclick-autoscroll.path"
+	rm -f  "$(DESTDIR)$(MANDIR)/man1/middleclick-autoscroll.1"
+	rm -rf "$(DESTDIR)$(DATADIR)/doc/middleclick-autoscroll"
+
+clean:
+	rm -f po/*.mo $(MANPAGE)