#!/usr/bin/make -f

#
# \brief  Prepare Genode build directory
# \author Christian Helmuth, Norman Feske
# \date   2008-08-14
#

MAKEOVERRIDES =

PLATFORM = $(MAKECMDGOALS)

PLATFORMS = arm_v6 arm_v7a arm_v8a riscv x86_32 x86_64 linux

usage:
	@echo
	@echo "Tool for preparing Genode build directories"
	@echo
	@echo "usage:"
	@echo
	@echo "  create_builddir <platform> [BUILD_DIR=<build-dir>]"
	@echo
	@echo "  <platform>   can be:"
	@$(foreach PLAT,$(PLATFORMS), \
	   echo "                  '$(PLAT)'";)
	@echo
	@echo "  The definition of BUILD_DIR is optional. If specified,"
	@echo "  <build-dir> is the location of the build directory to create."
	@echo "  If not specified, the build directory will be created at"
	@echo "  <genode-dir>/build/<platform>."
	@echo

#
# Determine Genode base directory based on the known location of the
# 'create_builddir' tool within the Genode source tree
#
GENODE_DIR ?= $(realpath $(dir $(MAKEFILE_LIST))/..)

#
# Define default location of the build directory if not explicitly specified
#
BUILD_DIR ?= $(GENODE_DIR)/build/$(PLATFORM)

#
# Sanity checks
#
ifneq ($(PLATFORM),)
   #
   # Check if platform is unknown
   #
   ifeq ($(filter $(PLATFORM),$(PLATFORMS)),)
      $(error Bad platform argument '$(PLATFORM)')
   endif

   #
   # Check if build directory exists already
   #
   ifneq ($(wildcard $(BUILD_DIR)),)
      $(error Build directory '$(BUILD_DIR)' already exists)
   endif
endif

SHELL := bash


#
# Convert GENODE_DIR to an absolute directory because the user
# may have specified a '~'-relative location or a pwd-relative
# location.
#
GENODE_ABS_DIR := $(realpath $(shell echo $(GENODE_DIR)))

#
# Define absolute path to the contrib directory as written to the
# 'etc/build.conf' file. We use 'abs_path' instead of 'realpath' because the
# contrib directory may not exist when the build directory is created. In this
# case, 'realpath' would return an empty string.
#
ifeq ($(CONTRIB_DIR),)
CONTRIB_ABS_DIR := $$(GENODE_DIR)/contrib
else
CONTRIB_ABS_DIR := $(abspath $(shell echo $(CONTRIB_DIR)))
endif

$(BUILD_DIR)/etc:
	@mkdir -p $@

BUILD_CONF_X86      := run_x86 run_boot_dir repos repos_x86
BUILD_CONF_ARM_V6   := run_arm_v6 run_boot_dir repos
BUILD_CONF_ARM_V7   := run_arm_v7 run_boot_dir repos repos_arm_v7
BUILD_CONF(arm_v6)  := $(BUILD_CONF_ARM_V6)
BUILD_CONF(arm_v7a) := $(BUILD_CONF_ARM_V7)
BUILD_CONF(arm_v8a) := run_arm_v8 run_boot_dir repos repos_arm_v8
BUILD_CONF(riscv)   := run_riscv run_boot_dir repos
BUILD_CONF(x86_32)  := run_x86_32 $(BUILD_CONF_X86)
BUILD_CONF(x86_64)  := run_x86_64 $(BUILD_CONF_X86)
BUILD_CONF(linux)   := run_kernel_linux repos

message: $(BUILD_DIR)/etc/build.conf
$(BUILD_DIR)/etc/build.conf:
	@echo "GENODE_DIR  := $(GENODE_ABS_DIR)" > $@
	@echo 'BASE_DIR    := $$(GENODE_DIR)/repos/base' >> $@
	@echo 'CONTRIB_DIR := $(CONTRIB_ABS_DIR)' >> $@
	@echo >> $@
	@for i in make_j ccache run; do \
		cat $(GENODE_DIR)/tool/builddir/build.conf/$$i; done >> $@
	@for i in ${BUILD_CONF(${PLATFORM})}; do \
		cat $(GENODE_DIR)/tool/builddir/build.conf/$$i; done >> $@

message: $(BUILD_DIR)/Makefile
$(BUILD_DIR)/Makefile:
	@ln -sf $(GENODE_ABS_DIR)/tool/builddir/build.mk $@

$(BUILD_DIR)/etc/build.conf: $(BUILD_DIR)/etc
$(BUILD_DIR)/etc/specs.conf: $(BUILD_DIR)/etc

#
# Detect host CPU architecture (needed for creating Linux build directory that
# matches the host system)
#
UNAME_MACHINE := $(shell uname -m)

SPEC_ARCH(i686)   := x86_32
SPEC_ARCH(x86_64) := x86_64
SPEC_ARCH(armv6l) := armv_v6
SPEC_ARCH(armv7l) := armv_v7

HOST_SPEC_ARCH := ${SPEC_ARCH(${UNAME_MACHINE})}

#
# SPECS definitions
#

SPECS(arm_v6)          := arm_v6
SPECS(arm_v7a)         := arm_v7a
SPECS(arm_v8a)         := arm_v8a
SPECS(riscv)           := riscv
SPECS(x86_32)          := x86_32
SPECS(x86_64)          := x86_64
SPECS(linux)           := $(HOST_SPEC_ARCH)

ifneq (${SPECS(${PLATFORM})},)
message: $(BUILD_DIR)/etc/specs.conf
$(BUILD_DIR)/etc/specs.conf:
	@echo "SPECS += ${SPECS(${PLATFORM})}" > $@
endif

$(PLATFORM): message
message:
	@echo "Successfully created build directory at $(BUILD_DIR)."
	@echo "Please adjust $(BUILD_DIR)/etc/build.conf according to your needs."

.PHONY: $(PLATFORM)