kumquat-buildroot/package/pkg-cargo.mk
Yann E. MORIN 049ea7b389 package/pkg-cargo: handle licensing terms for host-only packages
The licensing terms are inherited from the target variant to the host
variant: when the host _LICENSE is empty, then the value of the target
_LICENSE is used.

However, for the cargo infra, we want to append a little blurb about
vendored depndencies. If the package is a host-only, then it would
inherit the target _LICENSE, i.e. the variable without the leading
HOST_. If that is defined, this is inherited in the generic-package part
of the infra, but in the cargo infra, we saw an empty variable, and so
we would not add the vendoring blurb.

We can't move the condition appending that blurb, after we called into
the generic-package infra, otherwise in that case, we'd have the
opposite issue for packages that are both target and host packages,
where the blurb would be duplicated for host packages...

Instead, we workaround the issue by duplicating the heuristic to inherit
the target value, from the generic- into the cargo-package infra.

Signed-off-by: Yann E. MORIN <yann.morin@orange.com>
Signed-off-by: Arnout Vandecappelle <arnout@mind.be>
2023-11-04 17:49:30 +01:00

219 lines
7.3 KiB
Makefile

################################################################################
# Cargo package infrastructure
#
# This file implements an infrastructure that eases development of package
# .mk files for Cargo packages. It should be used for all packages that use
# Cargo as their build system.
#
# See the Buildroot documentation for details on the usage of this
# infrastructure
#
# In terms of implementation, this Cargo infrastructure requires the .mk file
# to only specify metadata information about the package: name, version,
# download URL, etc.
#
# We still allow the package .mk file to override what the different steps
# are doing, if needed. For example, if <PKG>_BUILD_CMDS is already defined,
# it is used as the list of commands to perform to build the package,
# instead of the default Cargo behaviour. The package can also define some
# post operation hooks.
#
################################################################################
BR_CARGO_HOME = $(DL_DIR)/br-cargo-home
PKG_COMMON_CARGO_ENV = \
CARGO_HOME=$(BR_CARGO_HOME)
# __CARGO_TEST_CHANNEL_OVERRIDE_DO_NOT_USE_THIS is needed to allow
# passing the -Z target-applies-to-host, which is needed together with
# CARGO_TARGET_APPLIES_TO_HOST to fix build problems when target
# architecture == host architecture.
# __CARGO_TEST_CHANNEL_OVERRIDE_DO_NOT_USE_THIS="nightly" is to allow
# using nighly features on stable releases, i.e features that are not
# yet considered stable.
#
# CARGO_UNSTABLE_HOST_CONFIG="true" enables the host specific
# configuration feature
#
# CARGO_UNSTABLE_TARGET_APPLIES_TO_HOST="true" enables the nightly
# configuration option target-applies-to-host value to be set
#
# CARGO_TARGET_APPLIES_TO_HOST="false" is actually setting the value
# for this feature, which we disable, to make sure builds where target
# arch == host arch work correctly
PKG_CARGO_ENV = \
$(PKG_COMMON_CARGO_ENV) \
__CARGO_TEST_CHANNEL_OVERRIDE_DO_NOT_USE_THIS="nightly" \
CARGO_UNSTABLE_HOST_CONFIG="true" \
CARGO_UNSTABLE_TARGET_APPLIES_TO_HOST="true" \
CARGO_TARGET_APPLIES_TO_HOST="false" \
CARGO_BUILD_TARGET="$(RUSTC_TARGET_NAME)" \
CARGO_HOST_RUSTFLAGS="$(addprefix -C link-args=,$(HOST_LDFLAGS))" \
CARGO_TARGET_$(call UPPERCASE,$(RUSTC_TARGET_NAME))_LINKER=$(notdir $(TARGET_CROSS))gcc
#
# This is a workaround for https://github.com/rust-lang/compiler-builtins/issues/420
# and should be removed when fixed upstream
#
ifeq ($(NORMALIZED_ARCH),arm)
PKG_CARGO_ENV += \
CARGO_TARGET_$(call UPPERCASE,$(RUSTC_TARGET_NAME))_RUSTFLAGS="-Clink-arg=-Wl,--allow-multiple-definition"
endif
HOST_PKG_CARGO_ENV = \
$(PKG_COMMON_CARGO_ENV) \
RUSTFLAGS="$(addprefix -C link-args=,$(HOST_LDFLAGS))"
################################################################################
# inner-cargo-package -- defines how the configuration, compilation and
# installation of a cargo package should be done, implements a few hooks
# to tune the build process for cargo specifities 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-cargo-package
# We need host-rustc to run cargo at download time (for vendoring),
# and at build and install time.
$(2)_DOWNLOAD_DEPENDENCIES += host-rustc
$(2)_DEPENDENCIES += host-rustc
$(2)_DOWNLOAD_POST_PROCESS = cargo
$(2)_DL_ENV += CARGO_HOME=$$(BR_CARGO_HOME)
# If building in a sub directory, use that to find the Cargo.toml
ifneq ($$($(2)_SUBDIR),)
$(2)_DL_ENV += BR_CARGO_MANIFEST_PATH=$$($(2)_SUBDIR)/Cargo.toml
endif
# Because we append vendored info, we can't rely on the values being empty
# once we eventually get into the generic-package infra. So, we duplicate
# the heuristics here
ifndef $(2)_LICENSE
ifdef $(3)_LICENSE
$(2)_LICENSE = $$($(3)_LICENSE)
endif
endif
# Due to vendoring, it is pretty likely that not all licenses are
# listed in <pkg>_LICENSE. If the license is unset, it is "unknown"
# so adding unknowns to some unknown is still some other unkown,
# so don't append the blurb in that case.
ifneq ($$($(2)_LICENSE),)
$(2)_LICENSE += , vendored dependencies licenses probably not listed
endif
# Note: in all the steps below, we "cd" into the build directory to
# execute the "cargo" tool instead of passing $(@D)/Cargo.toml as the
# manifest-path. Indeed while the latter seems to work, it in fact
# breaks in subtle ways as the way cargo searches for its
# configuration file is based (among other rules) on the current
# directory. This means that if cargo is started outside of a package
# directory, its configuration file will not be taken into account.
#
# Also, we pass:
# * --offline to prevent cargo from downloading anything: all
# dependencies should have been built by the download post
# process logic
# * --locked to force cargo to use the Cargo.lock file, which ensures
# that a fixed set of dependency versions is used
#
# Build step. Only define it if not already defined by the package .mk
# file.
#
ifndef $(2)_BUILD_CMDS
ifeq ($(4),target)
define $(2)_BUILD_CMDS
cd $$($$(PKG)_SRCDIR) && \
$$(TARGET_MAKE_ENV) \
$$(TARGET_CONFIGURE_OPTS) \
$$(PKG_CARGO_ENV) \
$$($(2)_CARGO_ENV) \
cargo build \
--offline \
$$(if $$(BR2_ENABLE_DEBUG),,--release) \
--manifest-path Cargo.toml \
--locked \
$$($(2)_CARGO_BUILD_OPTS)
endef
else # ifeq ($(4),target)
define $(2)_BUILD_CMDS
cd $$($$(PKG)_SRCDIR) && \
$$(HOST_MAKE_ENV) \
$$(HOST_CONFIGURE_OPTS) \
$$(HOST_PKG_CARGO_ENV) \
$$($(2)_CARGO_ENV) \
cargo build \
--offline \
--release \
--manifest-path Cargo.toml \
--locked \
$$($(2)_CARGO_BUILD_OPTS)
endef
endif # ifeq ($(4),target)
endif # ifndef $(2)_BUILD_CMDS
#
# Target installation step. Only define it if not already defined by
# the package .mk file.
#
ifndef $(2)_INSTALL_TARGET_CMDS
define $(2)_INSTALL_TARGET_CMDS
cd $$($$(PKG)_SRCDIR) && \
$$(TARGET_MAKE_ENV) \
$$(TARGET_CONFIGURE_OPTS) \
$$(PKG_CARGO_ENV) \
$$($(2)_CARGO_ENV) \
cargo install \
--offline \
--root $$(TARGET_DIR)/usr/ \
--bins \
--path ./ \
--force \
--locked \
-Z target-applies-to-host \
$$($(2)_CARGO_INSTALL_OPTS)
endef
endif
ifndef $(2)_INSTALL_CMDS
define $(2)_INSTALL_CMDS
cd $$($$(PKG)_SRCDIR) && \
$$(HOST_MAKE_ENV) \
$$(HOST_CONFIGURE_OPTS) \
$$(HOST_PKG_CARGO_ENV) \
$$($(2)_CARGO_ENV) \
cargo install \
--offline \
--root $$(HOST_DIR) \
--bins \
--path ./ \
--force \
--locked \
$$($(2)_CARGO_INSTALL_OPTS)
endef
endif
# Call the generic package infrastructure to generate the necessary
# make targets
$(call inner-generic-package,$(1),$(2),$(3),$(4))
endef
################################################################################
# cargo-package -- the target generator macro for Cargo packages
################################################################################
cargo-package = $(call inner-cargo-package,$(pkgname),$(call UPPERCASE,$(pkgname)),$(call UPPERCASE,$(pkgname)),target)
host-cargo-package = $(call inner-cargo-package,host-$(pkgname),$(call UPPERCASE,host-$(pkgname)),$(call UPPERCASE,$(pkgname)),host)