ada: runtime and library support

The Ada runtime can now be set with the ADA_RTS variable. The ada
library builds a (currently) minimal runtime from the gcc sources that
come with Genode (to stay consistent with the used compiler) and sets
the runtime path accordingly. It is build as a shared library ada.lib.so
which needs to be added to the build files.

I split the existing Ada test into program and library, and moved it
to libports as it depends on the runtime library residing in this
repository too.

Fixes #2748

repos/base/mk/generic.mk

@@ -7,7 +7,7 @@
 # Collect object files and avoid duplicates (by using 'sort')
 #
 SRC_O  += $(addprefix binary_,$(addsuffix .o,$(notdir $(SRC_BIN))))
-SRC     = $(sort $(SRC_C) $(SRC_CC) $(SRC_ADA) $(SRC_RS) $(SRC_S) $(SRC_O))
+SRC     = $(sort $(SRC_C) $(SRC_CC) $(SRC_ADB) $(SRC_ADS) $(SRC_RS) $(SRC_S) $(SRC_O))
 OBJECTS = $(addsuffix .o,$(basename $(SRC)))
 
 #
@@ -72,7 +72,11 @@ endif
 #
 %.o: %.adb
 	$(MSG_COMP)$@
-	$(VERBOSE)$(GNATMAKE) -q -c --GCC=$(CC) --RTS=$(PRG_DIR) $< -cargs $(CC_ADA_OPT) $(INCLUDES)
+	$(VERBOSE)$(GNATMAKE) -q -c --GCC=$(CC) --RTS=$(ADA_RTS) $< -cargs $(CC_ADA_OPT) $(INCLUDES)
+
+%.ali %.o: %.ads
+	$(MSG_COMP)$@
+	$(VERBOSE)$(CC) -c -gnatg -gnatp -gnatpg -gnatn2 -I- -I$(ADA_RTS_SOURCE) $(CC_ADA_OPT) $<
 
 #
 # Compiling Rust sources

repos/base/src/test/ada/README

@@ -1,13 +0,0 @@
-This directory contains a test for using freestanding Ada code with Genode.
-
-The program relies on the normal startup procedure of a Genode process.
-Execution starts at the 'crt0' assembly entry provided by the startup library.
-The 'crt0' code sets up the stack of the main thread and calls the '_main'
-function implemented in the C++ portion of Genode's startup library. In turn,
-the '_main' function calls 'main' of the actual program. The main function of
-this example calls the Ada main procedure. The test further exercises the call
-of C functions from Ada code. So the integration of Ada and C code is almost
-seamless.
-
-Please note that the current version of this program does not use 'gnatbind'.
-Therefore, package elaboration is not executed.

repos/base/src/test/ada/adainclude/system.ads

@@ -1,2 +0,0 @@
-Package System is
-end System;

repos/base/src/test/ada/target.mk

@@ -1,4 +0,0 @@
-TARGET   = test-ada
-SRC_ADA  = main.adb add_package.adb
-SRC_CC   = add.cc startup.cc
-LIBS     = base

repos/libports/lib/import/import-ada.mk

@@ -0,0 +1 @@
+ADA_RTS = $(BUILD_BASE_DIR)/var/libcache/ada

repos/libports/lib/import/import-test-ada.mk

@@ -0,0 +1 @@
+INC_DIR += $(REP_DIR)/src/test/ada/lib

repos/libports/lib/mk/ada.mk

@@ -0,0 +1,22 @@
+
+include $(REP_DIR)/lib/import/import-ada.mk
+ADALIB = $(ADA_RTS)/adalib
+ADAINCLUDE = $(ADA_RTS)/adainclude
+
+PACKAGES = system
+
+ADA_RTS_SOURCE = $(call select_from_ports,gcc)/src/noux-pkg/gcc/gcc/ada
+SRC_ADS += $(foreach package, $(PACKAGES), $(package).ads)
+
+vpath %.ads $(ADA_RTS_SOURCE)
+
+SHARED_LIB = yes
+
+all: ada_source_path ada_object_path
+
+ada_source_path: ada_object_path
+	$(VERBOSE)$(shell echo $(CONTRIB_DIR)/gcc-$(shell echo $(call _hash_of_port,gcc) | cut -d" " -f1)/src/noux-pkg/gcc/gcc/ada > $(ADA_RTS)/ada_source_path)
+
+ada_object_path:
+	$(VERBOSE)$(shell mkdir -p $(ADA_RTS))
+	$(VERBOSE)$(shell echo $(ADA_RTS) > $(ADA_RTS)/ada_object_path)

repos/libports/lib/mk/test-ada.mk

@@ -0,0 +1,6 @@
+LIBS    += base ada
+SRC_ADB += add_package.adb
+
+include $(REP_DIR)/lib/import/import-test-ada.mk
+
+vpath %.adb $(REP_DIR)/src/test/ada/lib

repos/libports/run/ada.run

@@ -20,7 +20,7 @@ install_config {
 	</config>
 }
 
-build_boot_image "core ld.lib.so init test-ada"
+build_boot_image "core ld.lib.so ada.lib.so init test-ada"
 
 append qemu_args "-nographic "
 

repos/libports/src/test/ada/README

@@ -0,0 +1,13 @@
+This directory contains an example Ada program on Genode.
+
+An Ada program relies on the normal startup procedure of Genode
+components, which calls 'Component::construct()' in _startup.cc_. It
+enters the Ada code by calling the Ada main procedure '_ada_main()'
+from 'Component::construct()'. Additionally, the test exercises calls
+of C functions from Ada code to demonstrate the almost seamless
+integration of Ada and C code and illustrates the implementation of
+Ada libraries in Genode. Ada programs require the _ada_ library as it
+provides the needed runtime.
+
+Please note that the current version of this program does not use
+'gnatbind'. Therefore, package elaboration is not executed.

repos/libports/src/test/ada/main.adb

@@ -1,5 +1,5 @@
 --
--- \brief  Ada test program that calls a external C functions
+-- \brief  Ada test program
 -- \author Norman Feske
 -- \date   2009-09-23
 --
@@ -20,6 +20,6 @@ procedure main is
 	pragma import(C, ext_c_print_int, "print_int");
 
 begin
-        add_package.Add(13, 14, result);
+	add_package.Add(13, 14, result);
 	ext_c_print_int(result);
 end main;

repos/libports/src/test/ada/target.mk

@@ -0,0 +1,4 @@
+TARGET   = test-ada
+SRC_ADB  = main.adb
+SRC_CC   = print.cc startup.cc
+LIBS     = base ada test-ada