tool/port: access to metadata of ports

Fixes #4685

tool/ports/metadata

@@ -0,0 +1,34 @@
+#!/usr/bin/make -f
+
+#
+# \brief  Tool for retrieving metadata of port sources
+# \author Christian Helmuth
+# \date   2023-01-20
+#
+
+ifndef VERBOSE
+MAKEFLAGS += --no-print-directory
+endif
+
+export GENODE_DIR := $(realpath $(dir $(MAKEFILE_LIST))/../..)
+
+usage:
+	@$(ECHO)
+	@$(ECHO) "Tool for retrieving version information of port sources"
+	@$(ECHO)
+	@$(ECHO) "usage:"
+	@$(ECHO)
+	@$(ECHO) "  $(notdir $(MAKEFILE_LIST)) <ports>"
+	@$(ECHO)
+	@$(ECHO) "  <ports>   whitespace-separated list of ports"
+	@$(ECHO)
+
+TARGETS = $(sort $(MAKECMDGOALS))
+
+.PHONY: $(TARGETS)
+
+.NOTPARALLEL:
+
+$(TARGETS):
+	@$(MAKE) -f $(GENODE_DIR)/tool/ports/mk/metadata_single_port.mk $@
+	@$(ECHO)

tool/ports/mk/metadata_single_port.mk

@@ -0,0 +1,54 @@
+#
+# \brief  Retrieve version information of port source
+# \author Christian Helmuth
+# \date   2023-01-20
+#
+
+PORTS_TOOL_DIR ?= $(GENODE_DIR)/tool/ports
+
+include $(GENODE_DIR)/tool/ports/mk/front_end.inc
+include $(GENODE_DIR)/tool/ports/mk/check_port_arg.inc
+
+#
+# Include definitions provided by the port description file
+#
+include $(PORT)
+
+.NOTPARALLEL:
+
+#
+# Assertion for the presence of a LICENSE and VERSION declarations in the port
+# description
+#
+ifeq ($(LICENSE),)
+$(TARGET): license_undefined
+license_undefined:
+	@$(ECHO) "Error: License undefined"; false
+endif
+
+ifeq ($(VERSION),)
+$(TARGET): version_undefined
+version_undefined:
+	@$(ECHO) "Error: Version undefined"; false
+endif
+
+info:
+	@$(ECHO) "PORT:     $(PORT_NAME)"
+	@$(ECHO) "LICENSE:  $(LICENSE)"
+	@$(ECHO) "VERSION:  $(VERSION)"
+
+%.file:
+	@$(ECHO) "SOURCE:   $(URL($*)) ($*)"
+
+%.archive:
+	@$(ECHO) "SOURCE:   $(URL($*)) ($*)"
+
+%.git:
+	@$(ECHO) "SOURCE:   $(URL($*)) git $(REV($*)) ($*)"
+
+%.svn:
+	@$(ECHO) "SOURCE:   $(URL($*)) svn $(REV($*)) ($*)"
+
+$(DOWNLOADS): info
+
+$(TARGET): $(DOWNLOADS)