build: add code coverage support

Build all targets, except for CLI tools (mmcli, uml290), with special
flags needed for collecting code coverage information when the build has
been configured with --enable-code-coverage.

Three new targets are available in the top build directory:

 - `check-code-coverage' runs the test suite and generates a code
   coverage report,

 - `code-coverage-capture' generates a code coverage report from already
   collected data, which can come in handy when one wants to see code
   paths touched by a particular test,

 - `code-coverage-clean' removes the collected coverage data and the
   generated reports.

14 files changed, 59 insertions, 6 deletions

diff --git a/.gitignore b/.gitignore
index 5888e9d9..2ce4de06 100644
--- a/.gitignore
+++ b/.gitignore
@@ -18,6 +18,8 @@ gtk-doc.make
 *.lo
 *.la
 *.loT
+*.gcno
+*.gcda
 libtool
 .deps
 .libs
@@ -165,3 +167,6 @@ plugins/test-service-*
 
 TAGS
 ABOUT-NLS
+
+ModemManager-*-coverage.info
+ModemManager-*-coverage/
diff --git a/Makefile.am b/Makefile.am
index f6bea8e1..762306ff 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -24,3 +24,10 @@ EXTRA_DIST = \
 	COPYING.LIB
 
 ACLOCAL_AMFLAGS = -I m4
+
+@CODE_COVERAGE_RULES@
+
+if CODE_COVERAGE_ENABLED
+clean-local:
+	-find $(top_builddir) -name "*.gcno" -delete
+endif
diff --git a/configure.ac b/configure.ac
index 9e8587dc..22417cc1 100644
--- a/configure.ac
+++ b/configure.ac
@@ -110,6 +110,9 @@ AC_SUBST(GLIB_MKENUMS)
 GDBUS_CODEGEN=`$PKG_CONFIG --variable=gdbus_codegen gio-2.0`
 AC_SUBST(GDBUS_CODEGEN)
 
+# Code coverage (disabled by default)
+AX_CODE_COVERAGE
+
 # GObject Introspection
 GOBJECT_INTROSPECTION_CHECK([0.9.6])
 
@@ -302,7 +305,13 @@ echo "
     compiler:                ${CC}
     cflags:                  ${CFLAGS}
     Maintainer mode:         ${USE_MAINTAINER_MODE}
+    Code coverage:           ${CODE_COVERAGE_ENABLED}"
+if test "x${CODE_COVERAGE_ENABLED}" = "xyes"; then
+	echo "    Code coverage cflags:    ${CODE_COVERAGE_CFLAGS}"
+	echo "    Code coverage ldflags:   ${CODE_COVERAGE_LDFLAGS}"
+fi
 
+echo "
     D-Bus system directory:  ${DBUS_SYS_DIR}
     udev base directory:     ${UDEV_BASE_DIR}
     systemd unit directory:  ${with_systemdsystemunitdir}
diff --git a/libmm-glib/Makefile.am b/libmm-glib/Makefile.am
index 54e79fc9..da1f5d4a 100644
--- a/libmm-glib/Makefile.am
+++ b/libmm-glib/Makefile.am
@@ -1,5 +1,8 @@
 SUBDIRS = generated . tests
 
+AM_CFLAGS = $(CODE_COVERAGE_CFLAGS)
+AM_LDFLAGS = $(CODE_COVERAGE_LDFLAGS)
+
 lib_LTLIBRARIES = libmm-glib.la
 
 libmm_glib_la_SOURCES = \
@@ -91,7 +94,8 @@ libmm_glib_la_LIBADD = \
 	$(LIBMM_GLIB_LIBS)
 
 libmm_glib_la_LDFLAGS = \
-	-version-info $(MM_GLIB_LT_CURRENT):$(MM_GLIB_LT_REVISION):$(MM_GLIB_LT_AGE)
+	-version-info $(MM_GLIB_LT_CURRENT):$(MM_GLIB_LT_REVISION):$(MM_GLIB_LT_AGE) \
+	$(AM_LDFLAGS)
 
 includedir = @includedir@/libmm-glib
 include_HEADERS = \
diff --git a/libmm-glib/generated/Makefile.am b/libmm-glib/generated/Makefile.am
index 2a608fc1..5a90b90d 100644
--- a/libmm-glib/generated/Makefile.am
+++ b/libmm-glib/generated/Makefile.am
@@ -1,6 +1,9 @@
 
 SUBDIRS = . tests
 
+AM_CFLAGS = $(CODE_COVERAGE_CFLAGS)
+AM_LDFLAGS = $(CODE_COVERAGE_LDFLAGS)
+
 noinst_LTLIBRARIES = libmm-generated.la
 
 GENERATED_H = \
diff --git a/libmm-glib/generated/tests/Makefile.am b/libmm-glib/generated/tests/Makefile.am
index a4bed421..0cebb720 100644
--- a/libmm-glib/generated/tests/Makefile.am
+++ b/libmm-glib/generated/tests/Makefile.am
@@ -1,4 +1,5 @@
-
+AM_CFLAGS = $(CODE_COVERAGE_CFLAGS)
+AM_LDFLAGS = $(CODE_COVERAGE_LDFLAGS)
 
 noinst_LTLIBRARIES = libmm-test-generated.la
 
diff --git a/libmm-glib/tests/Makefile.am b/libmm-glib/tests/Makefile.am
index be93d4c6..f98f9d7c 100644
--- a/libmm-glib/tests/Makefile.am
+++ b/libmm-glib/tests/Makefile.am
@@ -1,5 +1,8 @@
 include $(top_srcdir)/gtester.make
 
+AM_CFLAGS = $(CODE_COVERAGE_CFLAGS)
+AM_LDFLAGS = $(CODE_COVERAGE_LDFLAGS)
+
 noinst_PROGRAMS = test-common-helpers
 TEST_PROGS += $(noinst_PROGRAMS)
 
diff --git a/libqcdm/src/Makefile.am b/libqcdm/src/Makefile.am
index 9aa9500f..2caaf008 100644
--- a/libqcdm/src/Makefile.am
+++ b/libqcdm/src/Makefile.am
@@ -1,5 +1,7 @@
-noinst_LTLIBRARIES = libqcdm.la libqcdm-test.la
+AM_CFLAGS = $(CODE_COVERAGE_CFLAGS)
+AM_LDFLAGS = $(CODE_COVERAGE_LDFLAGS)
 
+noinst_LTLIBRARIES = libqcdm.la libqcdm-test.la
 
 libqcdm_la_CPPFLAGS = \
 	$(MM_CFLAGS)
diff --git a/libqcdm/tests/Makefile.am b/libqcdm/tests/Makefile.am
index 32599068..c00f1b01 100644
--- a/libqcdm/tests/Makefile.am
+++ b/libqcdm/tests/Makefile.am
@@ -1,5 +1,8 @@
 include $(top_srcdir)/gtester.make
 
+AM_CFLAGS = $(CODE_COVERAGE_CFLAGS)
+AM_LDFLAGS = $(CODE_COVERAGE_LDFLAGS)
+
 noinst_PROGRAMS = test-qcdm modepref ipv6pref reset
 TEST_PROGS += test-qcdm
 
diff --git a/libwmc/src/Makefile.am b/libwmc/src/Makefile.am
index 46205016..b662f892 100644
--- a/libwmc/src/Makefile.am
+++ b/libwmc/src/Makefile.am
@@ -1,5 +1,7 @@
-noinst_LTLIBRARIES = libwmc.la
+AM_CFLAGS = $(CODE_COVERAGE_CFLAGS)
+AM_LDFLAGS = $(CODE_COVERAGE_LDFLAGS)
 
+noinst_LTLIBRARIES = libwmc.la
 
 libwmc_la_CPPFLAGS = \
 	$(MM_CFLAGS)
diff --git a/libwmc/tests/Makefile.am b/libwmc/tests/Makefile.am
index 33eaf3de..4622fbcf 100644
--- a/libwmc/tests/Makefile.am
+++ b/libwmc/tests/Makefile.am
@@ -1,5 +1,8 @@
 include $(top_srcdir)/gtester.make
 
+AM_CFLAGS = $(CODE_COVERAGE_CFLAGS)
+AM_LDFLAGS = $(CODE_COVERAGE_LDFLAGS)
+
 noinst_PROGRAMS = test-wmc
 TEST_PROGS += $(noinst_PROGRAMS)
 
diff --git a/plugins/Makefile.am b/plugins/Makefile.am
index d2cbcb1c..c29364db 100644
--- a/plugins/Makefile.am
+++ b/plugins/Makefile.am
@@ -3,6 +3,9 @@ include $(top_srcdir)/gtester.make
 
 # Common CPPFLAGS and LDFLAGS
 
+AM_CFLAGS = $(CODE_COVERAGE_CFLAGS)
+AM_LDFLAGS = $(CODE_COVERAGE_LDFLAGS)
+
 PLUGIN_COMMON_COMPILER_FLAGS = \
 	$(MM_CFLAGS) \
 	$(GUDEV_CFLAGS)	\
@@ -13,13 +16,15 @@ PLUGIN_COMMON_COMPILER_FLAGS = \
 	-I$(top_builddir)/include \
 	-I$(top_srcdir)/libmm-glib \
 	-I$(top_srcdir)/libmm-glib/generated \
-	-I$(top_builddir)/libmm-glib/generated
+	-I$(top_builddir)/libmm-glib/generated \
+	$(AM_CFLAGS)
 
 PLUGIN_COMMON_LINKER_FLAGS = \
 	$(GUDEV_LIBS) \
 	$(MM_LIBS) \
 	-module \
-	-avoid-version
+	-avoid-version \
+	$(AM_LDFLAGS)
 
 if WITH_QMI
 PLUGIN_COMMON_COMPILER_FLAGS += $(QMI_CFLAGS)
diff --git a/src/Makefile.am b/src/Makefile.am
index 6912b00e..3b545ee2 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -8,6 +8,9 @@ udevrules_DATA = \
 	77-mm-usb-serial-adapters-greylist.rules \
 	80-mm-candidate.rules
 
+AM_CFLAGS = $(CODE_COVERAGE_CFLAGS)
+AM_LDFLAGS = $(CODE_COVERAGE_LDFLAGS)
+
 noinst_LTLIBRARIES = libmodem-helpers.la libport.la
 
 libmodem_helpers_la_CPPFLAGS = \
diff --git a/src/tests/Makefile.am b/src/tests/Makefile.am
index c52e4d1d..0804b14f 100644
--- a/src/tests/Makefile.am
+++ b/src/tests/Makefile.am
@@ -1,5 +1,8 @@
 include $(top_srcdir)/gtester.make
 
+AM_CFLAGS = $(CODE_COVERAGE_CFLAGS)
+AM_LDFLAGS = $(CODE_COVERAGE_LDFLAGS)
+
 noinst_PROGRAMS = \
 	test-modem-helpers \
 	test-charsets \