Makefile: Add dist and distcheck targets.

* Makefile (GIT, GPG, LZIP, distribute_files, dist_archive): New
variables.
(.PHONY): Add dist and distcheck.
(dist, $(dist_archive), distcheck): New targets.
(%.asc): New pattern rule.
(clean): Clean $(dist_archive) and $(dist_archive).asc.
* build-aux/distcheck.scm: New file.

2 files changed, 85 insertions, 2 deletions

diff --git a/Makefile b/Makefile
index ae1b4ed..59bc559 100644
--- a/Makefile
+++ b/Makefile
@@ -21,12 +21,18 @@ include Makefile.include
 
 GUILE = guile
 GUILD = guild
+GIT = git
+GPG = gpg
+LZIP = lzip
 EMACS = emacs
 
 top_level_module_dir = $(project)
 sources = $(wildcard $(top_level_module_dir)/*.scm)
 objects = $(sources:.scm=.go)
 tests = $(wildcard tests/*.scm)
+distribute_files = $(sources) $(tests) \
+		   COPYING NEWS.org README.org \
+		   guix.scm Makefile configure configure.scm
 
 scmdir = $(datarootdir)/guile/site/$(guile_effective_version)/$(top_level_module_dir)
 godir = $(libdir)/guile/$(guile_effective_version)/site-ccache/$(top_level_module_dir)
@@ -36,10 +42,24 @@ all: $(objects)
 %.go: %.scm
 	$(GUILD) compile -L . -o $@ $<
 
-.PHONY: check install clean
+.PHONY: check install clean dist distcheck
 check: $(tests)
 	$(GUILE) -L . $^
 
+dist_archive = $(project)-$(version).tar.lz
+
+dist: $(dist_archive) $(dist_archive).asc
+
+$(dist_archive): .git/refs/heads/main
+	$(GIT) archive --prefix $(basename $(basename $@))/ --format=tar main $(distribute_files) \
+		| $(LZIP) --force --output $@
+
+%.asc: %
+	$(GPG) --detach-sign --armor $<
+
+distcheck: $(dist_archive)
+	$(GUILE) build-aux/distcheck.scm $<
+
 install: $(sources) $(objects)
 	install -D $(sources) --target-directory $(scmdir)
 	install -D $(objects) --target-directory $(godir)
@@ -50,4 +70,4 @@ website/index.html: README.org build-aux/build-home-page.el
 	$(EMACS) -Q --batch --load build-aux/build-home-page.el --funcall build-website
 
 clean:
-	rm -f $(objects) Makefile.include website/index.html
+	rm -f $(objects) $(dist_archive) $(dist_archive).asc Makefile.include website/index.html
diff --git a/build-aux/distcheck.scm b/build-aux/distcheck.scm
new file mode 100644
index 0000000..4b08c66
--- /dev/null
+++ b/build-aux/distcheck.scm
@@ -0,0 +1,63 @@
+;;; kolam --- GraphQL implementation
+;;; Copyright © 2022 Arun Isaac <arunisaac@systemreboot.net>
+;;;
+;;; This file is part of kolam.
+;;;
+;;; kolam is free software; you can redistribute it and/or modify it
+;;; under the terms of the GNU Affero General Public License as
+;;; published by the Free Software Foundation; either version 3 of the
+;;; License, or (at your option) any later version.
+;;;
+;;; kolam is distributed in the hope that it will be useful, but
+;;; WITHOUT ANY WARRANTY; without even the implied warranty of
+;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+;;; Affero General Public License for more details.
+;;;
+;;; You should have received a copy of the GNU Affero General Public
+;;; License along with kolam.  If not, see
+;;; <http://www.gnu.org/licenses/>.
+
+(import (rnrs io ports)
+        (srfi srfi-26)
+        (ice-9 eval-string)
+        (ice-9 match)
+        (ice-9 popen)
+        (guix gexp)
+        (guix packages)
+        (guix scripts)
+        (guix store))
+
+(define (call-with-input-pipe command proc)
+  "Call PROC with input pipe to COMMAND. COMMAND is a list of program
+arguments."
+  (match command
+    ((prog args ...)
+     (let ((port #f))
+       (dynamic-wind
+         (lambda ()
+           (set! port (apply open-pipe* OPEN_READ prog args)))
+         (cut proc port)
+         (cut close-pipe port))))))
+
+(define (package-in-archive dist-archive)
+  "Return the package object in guix.scm of DIST-ARCHIVE."
+  (call-with-input-pipe (list "tar" "--extract" "--to-stdout"
+                              "--file" dist-archive
+                              (string-append
+                               (basename dist-archive ".tar.lz")
+                               "/guix.scm"))
+    (lambda (port)
+      (eval-string (get-string-all port)
+                   #:file (string-append (getcwd) "/guix.scm")))))
+
+(define (check-build dist-archive)
+  "Check if package in DIST-ARCHIVE builds correctly."
+  (run-with-store (open-connection)
+    (build-package
+     (package
+       (inherit (package-in-archive dist-archive))
+       (source (local-file dist-archive))))))
+
+(match (program-arguments)
+  ((_ dist-archive)
+   (check-build dist-archive)))