Add code coverage report generation

.gitignore

@@ -1,4 +1,3 @@
 bin/
 obj/
 coverage/
-test.info

.vscode/tasks.json

@@ -74,7 +74,7 @@
         {
             "label": "exec_unit_test",
             "type":"shell",
-            "command": "make exec_unit_test",
+            "command": "make exec_unit_test -j1",
             "problemMatcher": {
                 "base": "$gcc",
                 "owner": "gcc",
@@ -91,7 +91,7 @@
         {
             "label": "coverage",
             "type":"shell",
-            "command": "make coverage",
+            "command": "make coverage -j1",
             "problemMatcher": {
                 "base": "$gcc",
                 "owner": "gcc",

Makefile

@@ -6,10 +6,12 @@ CC = $(CROSS_COMPILE)gcc
 CPP = $(CROSS_COMPILE)cpp
 CHECK = cppcheck
 LCOV = lcov
+GENHTML = genhtml
 
 SRC_DIR = src
 OBJ_DIR = obj
 BIN_DIR = bin
+COVERAGE_DIR = coverage
 UNIT_TEST_SRC_DIR = test/unit
 UNIT_TEST_OBJ_DIR = $(OBJ_DIR)/$(UNIT_TEST_SRC_DIR)
 
@@ -18,8 +20,10 @@ INCLUDES += /usr/include/libftdi1
 
 ifneq "$(findstring $(MAKECMDGOALS), build_unit_test exec_unit_test coverage)" ""
 INCLUDES += test/inc
-C_FLAGS += -fprofile-arcs -ftest-coverage
-L_FLAGS += -fprofile-arcs -ftest-coverage
+
+C_FLAGS += --coverage
+L_FLAGS += --coverage
+
 else
 LIBS := ftdi1
 endif
@@ -45,16 +49,23 @@ THIS_MAKEFILE := $(lastword $(MAKEFILE_LIST))
 all: $(TARGET)
 
 .PHONY: coverage
-coverage: $(UNIT_TEST_TARGET)
-	$(UNIT_TEST_TARGET)
-	@rm -f $(UNIT_TEST_OBJ_DIR)/*.gcda
-	@rm -f $(UNIT_TEST_OBJ_DIR)/*.gcno
-	$(LCOV) -c -d obj -d bin/test/unit/ -d src/ -d test/unit/ -o test.info --no-external
-	$(eval COVERAGE:=$(shell genhtml -o coverage/html test.info | grep 'lines' | egrep -o '[0-9]+.[0-9]+%'))
+coverage: _cov_genhtml
+	$(eval COVERAGE:=$(shell grep 'lines' .coverage.tmp | egrep -o '[0-9]+.[0-9]+%'))
 	@echo
 	@echo Line coverage: $(COVERAGE)
 	@echo
+	@rm -f .coverage.tmp
 
+.PHONY: _cov_lcov
+_cov_lcov: exec_unit_test
+	@rm -f $(UNIT_TEST_OBJ_DIR)/*.gcda
+	@rm -f $(UNIT_TEST_OBJ_DIR)/*.gcno
+	@mkdir -p $(COVERAGE_DIR)
+	$(LCOV) -c -d $(OBJ_DIR) -o $(COVERAGE_DIR)/coverage.info
+
+.PHONY: _cov_genhtml
+_cov_genhtml: _cov_lcov
+	$(GENHTML) -o $(COVERAGE_DIR)/html $(COVERAGE_DIR)/coverage.info > .coverage.tmp
 
 .PHONY: unit_test
 build_unit_test: $(UNIT_TEST_TARGET)
@@ -95,8 +106,10 @@ $(UNIT_TEST_OBJ_DIR)/%.o: $(UNIT_TEST_SRC_DIR)/%.c $(UNIT_TEST_OBJ_DIR)/%.d
 
 .PHONY: clean
 clean:
-	rm -rf $(OBJS) $(patsubst %.o,%.d,$(OBJS)) $(TARGET)
-	rm -rf $(UNIT_TEST_OBJS) $(patsubst %.o,%.d,$(UNIT_TEST_OBJS)) $(UNIT_TEST_TARGET)
+	rm -f $(OBJS) $(patsubst %.o,%.d,$(OBJS)) $(TARGET)
+	rm -f $(UNIT_TEST_OBJS) $(patsubst %.o,%.d,$(UNIT_TEST_OBJS)) $(UNIT_TEST_TARGET)
+	rm -f $(OBJ_DIR)/*.gcda $(OBJ_DIR)/*.gcno
+	rm -fr $(COVERAGE_DIR)
 
 ifneq ($(MAKECMDGOALS),clean)
 -include $(patsubst %.o,%.d,$(OBJS))