Add gcov test coverage report

.gitignore

@@ -1,4 +1,7 @@
 *.exe
+*.gcda
+*.gcno
+*.gcov
 *.gz
 *.la
 *.lo
@@ -10,6 +13,7 @@
 *.cache
 *.plist
 *.stamp
+ABOUT-NLS
 aclocal.m4
 ar-lib
 autom4te.cache/
@@ -43,6 +47,8 @@ gtk-doc.m4
 gtk-doc.make
 include/libpsl.h
 install-sh
+lcov/
+libpsl.info
 libpsl.pc
 libtool
 ltmain.sh

Makefile.am

@@ -19,3 +19,13 @@ dist-hook:
 	mkdir -p $(distdir)/list/tests
 	cp -p $(PSL_FILE) $(distdir)/list
 	cp -p $(PSL_TESTFILE) $(distdir)/list/tests
+
+clean-local:
+	rm -rf */*.gc?? libpsl.info lcov
+
+check-coverage:
+	$(MAKE) clean
+	lcov --no-external --capture --initial --directory . --output-file libpsl.info
+	CFLAGS=$CFLAGS" --coverage" LDFLAGS=$LDFLAGS" --coverage" $(MAKE) check
+	lcov --no-external --capture --directory . --output-file libpsl.info
+	genhtml --prefix . --ignore-errors source libpsl.info --legend --title "libpsl" --output-directory=lcov

README.md

@@ -1,5 +1,6 @@
 [![Travis-CI Status](https://travis-ci.org/rockdaboot/libpsl.png?branch=master)](https://travis-ci.org/rockdaboot/libpsl)
 [![Coverity Scan](https://img.shields.io/coverity/scan/10227.svg)](https://scan.coverity.com/projects/rockdaboot-libpsl)
+[![Coverage Status](https://coveralls.io/repos/github/rockdaboot/libpsl/badge.svg?branch=master)](https://coveralls.io/github/rockdaboot/libpsl?branch=master)
 
 libpsl - C library to handle the Public Suffix List
 ===================================================