Merge remote-tracking branch 'r-autothing/v3/master'

1 files changed, 75 insertions, 0 deletions

diff --git a/build-aux/Makefile.once.head/10-gitfiles.mk b/build-aux/Makefile.once.head/10-gitfiles.mk
new file mode 100644
index 0000000..8566a7f
--- /dev/null
+++ b/build-aux/Makefile.once.head/10-gitfiles.mk
@@ -0,0 +1,75 @@
+# Copyright (C) 2016-2017  Luke Shumaker
+#
+# This program 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.
+#
+# 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 Affero General Public License for more details.
+#
+# You should have received a copy of the GNU Affero General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+mod.gitfiles.description = Automatically populate files.src.src from git
+mod.gitfiles.depends += files nested write-ifchanged quote
+mod.gitfiles.files += $(topsrcdir)/$(gitfiles.file)
+define mod.gitfiles.doc
+# Inputs:
+#   - Global variable    : `gitfiles.file` (Default: gitfiles.mk)
+#   - Directory variable : `nested.subdirs`
+#   - External           : git
+# Outputs:
+#   - File               : `$(topsrcdir)/$(gitfiles.file)`
+#   - Directory variable : `files.src.src`
+#   - Directory variable : `files.src.gen` (only in top dir)
+#
+# The `files` module has a variable (`files.src.src`) that you (the
+# developer) set to list "pure" source files; the type of files that you
+# would check into a version control system.  Since you are a
+# responsible developer, you use a version control system.  Since the
+# computer is already maintaining a list of these files *in the VCS*,
+# why should you--a filthy human--need to also maintain the list?  Enter
+# gitfiles, which will talk to git to maintain `files.src.src`, but
+# won't require that the git repository be distributed to
+# installing-users.
+#
+# If `$(topsrcdir)/.git` exists, then it will generate
+# `$(topsrcdir)/$(gitfiles.file)`.  Otherwise, it will assume that
+# `$(topsrcdir)/$(gitfiles.file)` already exists.
+#
+# It will use the information in `$(topsrcdir)/$(gitfiles.file)` to
+# append to `files.src.src` in each directory
+#
+# Finally, since the generated `$(topsrcdir)/$(gitfiles.file)` must be
+# distributed to users, it is added to $(topsrcdirs)'s `files.src.gen`.
+#
+# When setting `files.src.src`, it needs to know which files "belong" to
+# the current directory directly, and which "belong" to a further
+# subdirectory.  To do this, it uses an expression involving
+# `$(nested.subdirs)`.
+#
+# While gitfiles sets `files.src.src` very early in `each.head`, because
+# `nested.subdirs` might not be set yet, it may or may not be safe to
+# use the value of `$(files.src.src)` in your Makefile, depending on how
+# you set `nested.subdirs`.
+endef
+mod.gitfiles.doc := $(value mod.gitfiles.doc)
+
+gitfiles.file ?= gitfiles.mk
+
+_gitfiles.all =
+-include $(topsrcdir)/$(gitfiles.file)
+
+ifneq ($(wildcard $(topsrcdir)/.git),)
+$(topsrcdir)/$(gitfiles.file): _gitfiles.FORCE
+	@(cd $(@D) && git ls-files --recurse-submodules -z) | sed -z -e 's/\$$/\$$$$/g' -e 's/\n/$$(at.nl)/g' | xargs -r0 printf '_gitfiles.all+=%s\n' | $(WRITE_IFCHANGED) $@
+.PHONY: _gitfiles.FORCE
+endif
+
+_gitfiles.dir = $(call at.relto,$(topsrcdir),$(srcdir))
+_gitfiles.pat = $(patsubst ./%,%,$(_gitfiles.dir)/%)
+_gitfiles.dir.all = $(patsubst $(_gitfiles.pat),%,$(filter $(_gitfiles.pat),$(_gitfiles.all)))
+_gitfiles.dir.src = $(filter-out $(addsuffix /%,$(nested.subdirs)),$(_gitfiles.dir.all))