package/pkg-hare.mk: new infrastructure

Signed-off-by: Francois Perrad <francois.perrad.86@gmail.com>
[Julien: split long lines]
Signed-off-by: Julien Olivain <ju.o@free.fr>

DEVELOPERS

@@ -1203,6 +1203,7 @@ F:	package/lzlib/
 F:	package/moarvm/
 F:	package/opendoas/
 F:	package/perl*
+F:	package/pkg-hare.mk
 F:	package/pkg-perl.mk
 F:	package/pkg-luarocks.mk
 F:	package/quickjs/

docs/manual/adding-packages-hare.adoc

@@ -0,0 +1,87 @@
+// -*- mode:doc; -*-
+// vim: set syntax=asciidoc:
+
+=== Infrastructure for Hare packages
+
+[[hare-package-tutorial]]
+
+==== +hare-package+ tutorial
+
+The +Config.in+ file of Hare-based package 'hare-foo' should contain:
+
+----
+01: config BR2_PACKAGE_HARE_FOO
+02: 	bool "hare-foo"
+03: 	depends on BR2_PACKAGE_HOST_HARE_TARGET_ARCH_SUPPORTS
+04:	select BR2_PACKAGE_HOST_HARE
+05: 	help
+06: 	  This is a comment that explains what foo is.
+07:
+08: 	  https://foosoftware.org/foo/
+----
+
+And the +.mk+ file for this package should contain:
+
+----
+01: ################################################################################
+02: #
+03: # hare-foo
+04: #
+05: ################################################################################
+06:
+07: HARE_FOO_VERSION = 0.42.0
+08: HARE_FOO_SITE = https://git.sr.ht/~sircmpwn/hare-foo
+09: HARE_FOO_SITE_METHOD = git
+10: HARE_FOO_LICENSE = MPL-2.0
+11: HARE_FOO_LICENSE_FILES = COPYING
+12: HARE_FOO_INSTALL_STAGING = YES
+13:
+14: $(eval $(hare-package))
+----
+
+The Makefile starts with the definition of the standard variables for
+package declaration (lines 7 to 12).
+
+Finally, on line 14, we invoke the +hare-package+
+macro that generates all the Makefile rules that actually allows the
+package to be built.
+
+[[hare-package-reference]]
+
+==== +hare-package+ reference
+
+As a policy, packages that provide Hare modules should all be
+named +hare-<something>+ in Buildroot.
+
+In their +Config.in+ file, packages using the +hare-package+
+infrastructure should depend on +BR2_PACKAGE_HOST_HARE_TARGET_ARCH_SUPPORTS+
+because Buildroot will automatically add a dependency on +host-hare+
+to such packages.
+
+The main macro of the Hare package infrastructure is +hare-package+:
+like +generic-package+ it works by defining a number of variables providing
+metadata information about the package, and then calling the +hare-package+
+macro.
+
+Just like the generic infrastructure, the Hare infrastructure works
+by defining a number of variables before calling the +hare-package+
+macro.
+
+All the package metadata information variables that exist in the
+xref:generic-package-reference[generic package infrastructure] also
+exist in the Hare infrastructure.
+
+This infrastructure expects that the upstream package follows the
+https://harelang.org/documentation/usage/project-structure.html#makefiles[project structure conventions],
+because the upstream +Makefile+ is called.
+
+When the package contains Hare modules (ie. libraries),
+there are not compiled by this BR package,
+there are just installed in +$(STAGING_DIR)/usr/src/hare/third-party+,
+for a future use.
+
+When the package produces one or more executables,
+all Hare sources (from this package, from dependent modules,
+from the Hare stdlib) are compiled and statically linked.
+If a binding to a native library is used,
+the link requires the static library, not the shared one.

docs/manual/adding-packages.adoc

@@ -43,6 +43,8 @@ include::adding-packages-golang.adoc[]
 
 include::adding-packages-qmake.adoc[]
 
+include::adding-packages-hare.adoc[]
+
 include::adding-packages-kernel-module.adoc[]
 
 include::adding-packages-asciidoc.adoc[]

package/Makefile.in

@@ -474,3 +474,4 @@ include package/pkg-golang.mk
 include package/pkg-meson.mk
 include package/pkg-qmake.mk
 include package/pkg-cargo.mk
+include package/pkg-hare.mk

package/pkg-hare.mk

@@ -0,0 +1,99 @@
+################################################################################
+# Hare package infrastructure
+# see https://harelang.org/
+#
+# This file implements an infrastructure that eases development of
+# package .mk files for Hare packages.
+#
+# See the Buildroot documentation for details on the usage of this
+# infrastructure
+#
+# In terms of implementation, this Hare infrastructure requires
+# the .mk file to only specify metadata information about the
+# package: name, version, etc.
+#
+################################################################################
+
+HARE_RUN_CMD = \
+	PATH=$(BR_PATH) \
+	HAREPATH="$(HOST_DIR)/src/hare/stdlib:$(STAGING_DIR)/usr/src/hare/third-party" \
+	$(HOST_DIR)/bin/hare
+HARE_ARCH_OPT = -a $(ARCH)
+HARE_LIBDIR_OPT = -L $(STAGING_DIR)/usr/lib
+
+################################################################################
+# inner-hare-package -- defines how the configuration, compilation and
+# installation of a Hare package should be done, implements a few hooks to
+# tune the build process and calls the generic package infrastructure to
+# generate the necessary make targets
+#
+#  argument 1 is the lowercase package name
+#  argument 2 is the uppercase package name, including a HOST_ prefix
+#             for host packages
+#  argument 3 is the uppercase package name, without the HOST_ prefix
+#             for host packages
+#  argument 4 is the type (target or host)
+################################################################################
+
+define inner-hare-package
+
+$(2)_DEPENDENCIES += host-hare
+
+#
+# Build step. Only define it if not already defined by the package .mk
+# file.
+#
+ifndef $(2)_BUILD_CMDS
+# in perfect world, all project follows the conventions described in
+# https://harelang.org/documentation/usage/project-structure.html#makefiles
+# but in real world, the target "all" is not always the default one
+define $(2)_BUILD_CMDS
+	if grep "^all:" $$($(2)_SRCDIR)Makefile > /dev/null; then \
+		$(MAKE) -C $$($(2)_SRCDIR) HARE="$$(HARE_RUN_CMD)" HAREFLAGS="$$(HARE_ARCH_OPT) $$(HARE_LIBDIR_OPT)" all; \
+	else \
+		$(MAKE) -C $$($(2)_SRCDIR) HARE="$$(HARE_RUN_CMD)" HAREFLAGS="$$(HARE_ARCH_OPT) $$(HARE_LIBDIR_OPT)"; \
+	fi
+endef
+endif
+
+#
+# Staging installation step. Only define it if not already defined by
+# the package .mk file.
+#
+ifndef $(2)_INSTALL_STAGING_CMDS
+define $(2)_INSTALL_STAGING_CMDS
+	$(MAKE) -C $$($(2)_SRCDIR) PREFIX=/usr DESTDIR="$$(STAGING_DIR)" install
+endef
+endif
+
+#
+# Target installation step. Only define it if not already defined by
+# the package .mk file.
+#
+ifndef $(2)_INSTALL_TARGET_CMDS
+define $(2)_INSTALL_TARGET_CMDS
+	$(MAKE) -C $$($(2)_SRCDIR) PREFIX=/usr DESTDIR="$$(TARGET_DIR)" install
+endef
+endif
+
+# Call the generic package infrastructure to generate the necessary
+# make targets
+$(call inner-generic-package,$(1),$(2),$(3),$(4))
+
+endef
+
+################################################################################
+# hare-package -- the target generator macro for Hare packages
+################################################################################
+
+hare-package = $(call inner-hare-package,$(pkgname),$(call UPPERCASE,$(pkgname)),$(call UPPERCASE,$(pkgname)),target)
+
+################################################################################
+# Cleanup target /usr/src/hare
+################################################################################
+
+define HARE_FINALIZE_TARGET
+	rm -rf $(TARGET_DIR)/usr/src/hare
+endef
+
+TARGET_FINALIZE_HOOKS += HARE_FINALIZE_TARGET