add a gcov target (#498)

"make gcov" is sufficient to run the tests in DEBUG mode and generate gcov
output for each .c file in lib/, to give us some idea of our coverage.

Signed-off-by: John Levon <john.levon@nutanix.com>
Reviewed-by: Swapnil Ingle <swapnil.ingle@nutanix.com>

4 files changed, 34 insertions, 26 deletions

diff --git a/.gitignore b/.gitignore
index c4a5874..372611c 100644
--- a/.gitignore
+++ b/.gitignore
@@ -2,3 +2,4 @@
 build
 cscope.out
 tags
+lib/*.gcov
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 8715625..10086ba 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -39,6 +39,9 @@ include(GNUInstallDirs)
 find_package(PkgConfig REQUIRED)
 pkg_check_modules(JSON REQUIRED json-c)
 
+# for the benefit of the gcov rules
+set(CMAKE_C_OUTPUT_EXTENSION_REPLACE 1)
+
 include_directories(${CMAKE_SOURCE_DIR}/include)
 include_directories(${CMAKE_SOURCE_DIR}/lib)
 include_directories(${JSON_INCLUDE_DIRS})
diff --git a/Makefile b/Makefile
index aae9071..f3b7779 100644
--- a/Makefile
+++ b/Makefile
@@ -43,6 +43,11 @@ ifdef WITH_ASAN
 	LDFLAGS += -fsanitize=address
 endif
 
+ifeq ($(MAKECMDGOALS), gcov)
+	CFLAGS += --coverage
+	LDFLAGS += --coverage
+endif
+
 ifeq ($(VERBOSE),)
     MAKEFLAGS += -s
 endif
@@ -54,10 +59,10 @@ BUILD_DIR = $(BUILD_DIR_BASE)/$(BUILD_TYPE)
 
 INSTALL_PREFIX ?= /usr/local
 
-PHONY_TARGETS := all pytest pytest-valgrind test pre-push realclean buildclean force_cmake tags
-.PHONY: $(PHONY_TARGETS)
+.PHONY: all test pytest pytest-valgrind
+.PHONY: pre-push clean realclean tags gcov
 
-all $(filter-out $(PHONY_TARGETS), $(MAKECMDGOALS)): $(BUILD_DIR)/Makefile
+all: $(BUILD_DIR)/Makefile
 	+$(MAKE) -C $(BUILD_DIR) $@
 
 #
@@ -106,7 +111,11 @@ pytest-valgrind: all
 
 endif
 
+ifdef WITH_GCOV
+test: all pytest
+else
 test: all pytest
+endif
 	cd $(BUILD_DIR)/test; ctest --verbose
 
 pre-push: realclean
@@ -119,13 +128,16 @@ pre-push: realclean
 	make test CC=gcc
 	make pytest-valgrind
 
-realclean:
-	rm -rf $(BUILD_DIR_BASE)
+GCOVS=$(patsubst %.c,%.c.gcov, $(wildcard lib/*.c))
+
+gcov: realclean test $(GCOVS)
 
-buildclean:
+clean:
 	rm -rf $(BUILD_DIR)
 
-force_cmake: $(BUILD_DIR)/Makefile
+realclean:
+	rm -rf $(BUILD_DIR_BASE)
+	rm -rf $(GCOVS)
 
 $(BUILD_DIR)/Makefile:
 	mkdir -p $(BUILD_DIR)
@@ -139,3 +151,6 @@ $(BUILD_DIR)/Makefile:
 
 tags:
 	ctags -R --exclude=$(BUILD_DIR)
+
+lib/%.c.gcov: lib/%.c
+	cd lib && gcov -o ../build/$(BUILD_TYPE)/lib/CMakeFiles/$*.dir/$*.gcno $<
diff --git a/lib/CMakeLists.txt b/lib/CMakeLists.txt
index 874c622..5605a9f 100644
--- a/lib/CMakeLists.txt
+++ b/lib/CMakeLists.txt
@@ -46,6 +46,14 @@ set(LIBOBJS
     $<TARGET_OBJECTS:pci>
     $<TARGET_OBJECTS:tran_sock>)
 
+add_library(pci_caps OBJECT pci_caps.c)
+add_library(dma OBJECT dma.c)
+add_library(irq OBJECT irq.c)
+add_library(libvfio-user OBJECT libvfio-user.c)
+add_library(migration OBJECT migration.c)
+add_library(pci OBJECT pci.c)
+add_library(tran_sock OBJECT tran_sock.c)
+
 add_library(vfio-user-shared SHARED ${LIBOBJS})
 target_link_libraries(vfio-user-shared json-c pthread)
 set_target_properties(vfio-user-shared PROPERTIES
@@ -65,25 +73,6 @@ set_target_properties(vfio-user-static PROPERTIES
                       OUTPUT_NAME vfio-user
                       CLEAN_DIRECT_OUTPUT 1)
 
-set(UT_CFLAGS "-O0 -ggdb --coverage")
-set(UT_LFLAGS "--coverage")
-
-function(add_library_ut lib)
-    add_library(${lib} OBJECT ${ARGN})
-    set(lib_ut ${lib}_ut)
-    add_library(${lib_ut} ${ARGN})
-    set_target_properties(${lib_ut} PROPERTIES COMPILE_FLAGS ${UT_CFLAGS})
-    set_target_properties(${lib_ut} PROPERTIES LINK_FLAGS    ${UT_LFLAGS})
-endfunction(add_library_ut)
-
-add_library_ut(pci_caps pci_caps.c)
-add_library_ut(dma dma.c)
-add_library_ut(irq irq.c)
-add_library_ut(libvfio-user libvfio-user.c)
-add_library_ut(migration migration.c)
-add_library_ut(pci pci.c)
-add_library_ut(tran_sock tran_sock.c)
-
 install(TARGETS vfio-user-shared
         LIBRARY DESTINATION ${CMAKE_INSTALL_LIBDIR})