# SPDX-License-Identifier: GPL-2.0
#
# Build one test_progs flavor or test_maps.
# Invoked by the main Makefile after shared build inputs are ready.
# Flavored outputs live in $(OUTPUT)/$(FLAVOR); unflavored outputs
# share $(OUTPUT) with the main Makefile.
#
# Command-line parameters:
#   OUTPUT         selftests output directory, resolved by lib.mk
#   RUNNER         test_progs | test_maps
#   FLAVOR         empty | no_alu32 | cpuv4 | bpf_gcc
#   TESTS_DIR      prog_tests | map_tests
#   BPF_*          see Makefile.skel; BPF_CC is empty for test_maps
#   CC, CLANG      compilers resolved by the main Makefile
#   CFLAGS, LDFLAGS assembled flags, including lib.mk's additions
#
# Exported by the main Makefile:
#   LLVM_LDLIBS, LLVM_LDFLAGS: LLVM feature-probe results

include ../../../build/Build.include
include ../../../scripts/Makefile.arch
include ../../../scripts/Makefile.include

# Same message helpers as ../lib.mk, which only the top level includes.
ifeq ($(V),1)
Q =
msg =
else
Q = @
msg = @printf '  %-8s%s %s%s\n' "$(1)" "$(if $(2), [$(2)])" "$(notdir $(3))" "$(if $(4), $(4))";
MAKEFLAGS += --no-print-directory
endif

include Makefile.buildvars

BINARY := $(RUNNER)$(if $(FLAVOR),-$(FLAVOR))
RDIR   := $(OUTPUT)$(if $(FLAVOR),/$(FLAVOR))

all: $(OUTPUT)/$(BINARY)
.PHONY: all

# Delete partially updated (corrupted) files on error
.DELETE_ON_ERROR:

# No built-in rules: every file built here has an explicit rule, and the
# objects that come from the main Makefile have to be an error when
# missing rather than a silent rebuild by the built-in %.o recipes.
MAKEFLAGS += -r

# Permissive build behaviour (skip-on-failure compile, partial-link) only
# applies to test_progs and its flavors; runners that use strong cross-object
# references (e.g. test_maps) keep strict semantics even when permissive.
PERMISSIVE_TESTS := $(if $(filter test_progs,$(RUNNER)),$(PERMISSIVE))

$(RDIR):
	$(call msg,MKDIR,,$@)
	$(Q)mkdir -p $@

# Per-runner sources

ifeq ($(RUNNER),test_progs)
GENERATED_HDRS := $(LIBARENA_SKEL) $(LIBARENA_ASAN_SKEL)
endif

TEST_SRCS  := $(notdir $(wildcard $(TESTS_DIR)/*.c))
TEST_OBJS  := $(patsubst %.c,$(RDIR)/%.test.o,$(TEST_SRCS))
TEST_DEPS  := $(TEST_OBJS:.o=.d)

# BPF objects and skeletons - rules shared with the main Makefile

include Makefile.skel

# When the compiler generates a %.d file, only skel basenames (not
# full paths) are specified as prerequisites for corresponding %.o
# file. vpath directives below instruct make to search for skel files
# in $(RDIR), if they are not present in the working directory.
vpath %.skel.h $(RDIR)
vpath %.lskel.h $(RDIR)
vpath %.subskel.h $(RDIR)

# Test objects and runner binary

$(RDIR)/resolve_btfids.test.o: $(RESOLVE_BTFIDS) $(RDIR)/btf_data.bpf.o
$(RDIR)/resolve_btfids.test.o: private TEST_NEEDS_BTFIDS = 1

# compile individual test files
# Note: we cd into output directory to ensure embedded BPF object is found
# The %.test.d dependency files are a side effect of the -MMD below; the
# separate no-recipe rule for them orders the first compilation after
# skeleton generation and re-orders test object compilation when headers
# change.
$(TEST_OBJS): $(RDIR)/%.test.o: $(TESTS_DIR)/%.c | $(RDIR)/%.test.d
	$(call msg,TEST-OBJ,$(BINARY),$@)
	$(Q)(cd $(@D) && $(CC) -I. $(CFLAGS) -MMD -MT $@ -c $(CURDIR)/$< $(LDLIBS) -o $(@F)) $(if \
		$(PERMISSIVE_TESTS),$(call skip_on_fail,TEST))
	$(if $(TEST_NEEDS_BTFIDS),					\
		$(Q)if [ -f $@ ]; then					\
		$(if $(filter 1,$(V)),true,printf '  %-8s%s %s\n' "BTFIDS" " [$(BINARY)]" "$(notdir $@)"); \
		$(RESOLVE_BTFIDS) --btf $(RDIR)/btf_data.bpf.o $@;	\
		$(RESOLVE_BTFIDS) --patch_btfids $@.BTF_ids $@;		\
		fi)

$(TEST_DEPS): $(RDIR)/%.test.d: $(TESTS_DIR)/%.c $(GENERATED_HDRS) $(BPFOBJ) \
	      | $(RDIR) $(ALL_SKELS)

include $(wildcard $(TEST_DEPS))

cmd_runner_link = $(CC) $(CFLAGS) \
	$(if $(PERMISSIVE_TESTS),$(wildcard $(TEST_OBJS)) \
		$(filter-out $(TEST_OBJS),$(filter %.a %.o,$^)), \
		$(filter %.a %.o,$^)) \
	$(LDLIBS) $(LLVM_LDLIBS) $(LDFLAGS) $(LLVM_LDFLAGS) -o $@

# BPF objects are also needed at runtime.
# In permissive mode, existing test objects are normal prerequisites
# so edits trigger relinking. Order-only prerequisites attempt all
# tests; the recipe links the objects that exist afterward.
$(OUTPUT)/$(BINARY): $(if $(PERMISSIVE_TESTS),$(wildcard $(TEST_OBJS)),$(TEST_OBJS)) \
		     $(RUNNER_OBJS-$(RUNNER)) $(BPFOBJ)			\
		     $(TRUNNER_BPFTOOL)					\
		     | $(BPF_OBJS)					\
		     $(if $(PERMISSIVE_TESTS),$(TEST_OBJS))
	$(call msg,BINARY,,$@)
	$(Q)$(cmd_runner_link)
	$(Q)ln -sf $(if $(FLAVOR),..,.)/tools/build/bpftool/$(USE_BOOTSTRAP)bpftool $(RDIR)/bpftool