build: make meson the default build system

We still support autotools for now, but it is no longer the default.

Makefile.meson

@@ -0,0 +1,43 @@
+## Copyright (C) 2008-2021 Dirk-Jan C. Binnema <djcb@djcbsoftware.nl>
+##
+## This program is free software; you can redistribute it and/or modify
+## it under the terms of the GNU General Public License as published by
+## the Free Software Foundation; either version 3 of the License, or
+## (at your option) any later version.
+##
+## This program 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 General Public License for more details.
+##
+## You should have received a copy of the GNU General Public License
+## along with this program; if not, write to the Free Software Foundation,
+## Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+
+
+# Makefile with some useful targets for meson/ninja
+
+NINJA    ?= ninja
+BUILDDIR ?= $(CURDIR)/build
+MESON    ?= meson
+
+all: $(BUILDDIR)
+	$(NINJA) -C $(BUILDDIR)
+
+$(BUILDDIR):
+	$(MESON) $(BUILDDIR)
+
+check: test
+
+test: $(BUILDDIR)
+	@cd $(BUILDDIR); $(MESON) test
+
+dist: $(BUILDDIR)
+	@cd $(BUILDDIR); $(MESON) dist
+
+install: $(BUILDDIR)
+	@cd $(BUILDDIR); $(MESON) install
+
+clean:
+	@test -d $(BUILDDIR) && $(NINJA) -C $(BUILDDIR) clean
+

autogen.sh

@@ -1,34 +1,29 @@
 #!/bin/sh
 # Run this to generate all the initial makefiles, etc.
 
+echo "*** meson build setup"
+
 test -f mu/mu.cc || {
     echo "*** Run this script from the top-level mu source directory"
     exit 1
 }
 
-# opportunistically; usually not needed, but occasionally it'll
-# avoid build errors that would otherwise confuse users.
-test -f Makefile && {
-    echo "*** clear out old things"
-    make distclean 2> /dev/null
-}
-
+BUILDDIR=build
 
-command -V autoreconf > /dev/null
+command -v meson 2> /dev/null
 if [ $? != 0 ]; then
-    echo "*** No autoreconf found, please install it ***"
+    echo "*** No meson found, please install it ***"
     exit 1
 fi
 
-rm -f config.cache
-rm -rf autom4te.cache
-
-autoreconf --force --install --verbose || exit $?
-
-if test -z "$*"; then
-    echo "# Configuring without parameters"
+# we could remove build/ but let's avoid rm -rf risks...
+if test -d ${BUILDDIR}; then
+    meson --reconfigure ${BUILDDIR}
 else
-   echo "# Configure with parameters $*"
+    meson ${BUILDDIR} $@
 fi
 
-./configure --config-cache $@
+# Add a Makefile with some useful target
+cp Makefile.meson Makefile
+
+echo "*** Now run 'ninja -C ${BUILDDIR}' to build mu"

configure.ac

@@ -363,6 +363,10 @@ AS_IF([test "x$ac_cv_header_wordexp_h" != "xyes"],[
    echo "    --maildir=/home/user/Maildir"
 ])
 
+
+echo "NOTE: autotools support has been deprecated and will be removed"
+echo "      after the next stable release. use the meson build instead"
+
 echo
 echo "Now, type 'make' (or 'gmake') to build mu"
 echo

mu4e/meson.build

@@ -23,7 +23,7 @@ mu4e_meta = configure_file(
       'VERSION'         : meson.project_version(),
       # project_build_root() with meson >= 0.56
       'abs_top_builddir': join_paths(meson.build_root()),
-      'MU_DOC_DIR'      : join_paths(datadir, 'doc', 'mu')
+      'MU_DOC_DIR'      : join_paths(datadir, 'doc', 'mu'),
     })
 
 
@@ -53,6 +53,13 @@ mu4e_srcs=[
   'obsolete/org-mu4e.el',
 ]
 
+
+#
+# with (development) emacs 28.50 / native compilation this doesn't
+# _quite_ work; see: https://debbugs.gnu.org/db/47/47987.html
+#
+lispdir =  join_paths(datadir, 'emacs', 'site-lisp', 'mu4e')
+
 foreach src : mu4e_srcs
   target_name= '@BASENAME@.elc'
   target_path = join_paths(meson.current_build_dir(), target_name)
@@ -61,6 +68,8 @@ foreach src : mu4e_srcs
 		build_by_default: true,
 		input: src,
 		output: target_name,
+                install_dir: lispdir,
+                install: true,
 		command: [emacs,
 			  '--no-init-file',
 			  '--batch',
@@ -70,6 +79,9 @@ foreach src : mu4e_srcs
 			  '--funcall', 'batch-byte-compile', '@INPUT@'])
 endforeach
 
+# also install the sources.
+install_data(mu4e_srcs, install_dir: lispdir)
+
 
 if makeinfo.found()
   custom_target('mu4e_info',

mu4e/mu4e.texi

@@ -266,38 +266,20 @@ details depend on your distribution. If you're using another
 distribution (or another OS), the below can at least be helpful in
 identifying the packages to install.
 
-We provide some instructions for Debian, Ubuntu and Fedora; if those do not
-apply to you, you can follow either @ref{Building from a release tarball} or
-@ref{Building from git}.
+We provide some instructions for Debian, Ubuntu and Fedora; if those
+do not apply to you, you can follow either @ref{Building from a
+release tarball} or @ref{Building from git}.
 
 @subsection Dependencies for Debian/Ubuntu
 
 @example
-$ sudo apt-get install libgmime-3.0-dev libxapian-dev
-
-# get emacs 25 or higher if you don't have it yet
-$ sudo apt-get install emacs
-
-# optional
-$ sudo apt-get install guile-2.2-dev html2text xdg-utils
-
-# optional: only needed for msg2pdf and mug (toy gtk+ frontend)
-$ sudo apt-get install libwebkitgtk-3.0-dev
+$ sudo apt-get install libgmime-3.0-dev libxapian-dev emacs
 @end example
 
 @subsection Dependencies for Fedora
 
 @example
-$ sudo yum install gmime30-devel xapian-core-devel
-
-# get emacs 25 or higher if you don't have it yet
-$ sudo yum install emacs
-
-# optional
-$ sudo yum install html2text xdg-utils guile22-devel
-
-# optional: only needed for msg2pdf and mug (toy gtk+ frontend)
-$ sudo yum install webkitgtk3-devel
+$ sudo yum install gmime30-devel xapian-core-devel emacs
 @end example
 
 @subsection Building on Msys2
@@ -348,10 +330,18 @@ Xapian, GMime and their dependencies must be installed.
 @subsection Building from git
 @anchor{Building from git}
 
-Alternatively, if you build from the git repository or use a tarball
-like the ones that @t{github} produces, the instructions are slightly
-different, and require you to have autotools (@t{autoconf},
-@t{automake}, @t{libtool}, @t{texinfo}) installed:
+By default, @t{mu} use the Meson@footnote{@url{https://mesonbuild.com/}} build-system.
+
+@example
+$ git clone git://github.com/djcb/mu.git
+$ cd mu
+$ meson build && ninja -C build
+$ sudo ninja -C install
+@end example
+
+For now, you can also use the (deprecated) @t{autotools} build setup,
+assuming you have autotools (@t{autoconf}, @t{automake}, @t{libtool},
+@t{texinfo}) installed:
 
 @example
 # get from git (alternatively, use a github tarball)
@@ -368,29 +358,18 @@ $ sudo make install
 After this, @t{mu} and @t{mu4e} should be installed @footnote{there's
 a hard dependency between versions of @t{mu4e} and @t{mu} --- you
 cannot combine different versions} on your system, and be available
-from the command line and in  Emacs.
+from the command line and in Emacs.
 
 You may need to restart Emacs, so it can find @t{mu4e} in its
 @code{load-path}. If, even after restarting, Emacs cannot find
-@t{mu4e}, you may need to add it to your @code{load-path} explicitly; check
-where @t{mu4e} is installed, and add something like the following to your
-configuration before trying again:
+@t{mu4e}, you may need to add it to your @code{load-path} explicitly;
+check where @t{mu4e} is installed, and add something like the
+following to your configuration before trying again:
 @lisp
 ;; the exact path may differ --- check it
 (add-to-list 'load-path "/usr/local/share/emacs/site-lisp/mu4e")
 @end lisp
 
-@subsection Building using the meson build system
-
-As an (experimental) alternative to the @t{autotools}-build, it is possible to use
-the Meson@footnote{@url{https://mesonbuild.com/}} build-system instead.
-
-@example
-$ git clone git://github.com/djcb/mu.git
-$ cd mu
-$ meson build && ninja -C build
-$ sudo ninja -C install
-@end example
 
 @subsection mu4e and emacs customization