doc: add doxygen-coverage target

This makes it easier for anyone to get a coverage report for the doxygen
documentation through a simple "make doxygen-coverage".

Signed-off-by: Benjamin Cabé <benjamin@zephyrproject.org>

doc/CMakeLists.txt

@@ -118,6 +118,27 @@ set_target_properties(
     ADDITIONAL_CLEAN_FILES "${DOXY_OUT}"
 )
 
+#-------------------------------------------------------------------------------
+# Doxygen Coverage
+
+add_custom_target(
+  doxygen-coverage
+  COMMAND ${PYTHON_EXECUTABLE} -m coverxygen
+    --xml-dir ${CMAKE_CURRENT_BINARY_DIR}/doxygen/xml/
+    --src-dir ${ZEPHYR_BASE}/include/
+    --output ${CMAKE_CURRENT_BINARY_DIR}/doc-coverage.info
+  COMMAND lcov
+    --remove ${CMAKE_CURRENT_BINARY_DIR}/doc-coverage.info "*/deprecated"
+    > ${CMAKE_CURRENT_BINARY_DIR}/new.info
+  COMMAND genhtml
+    --no-function-coverage
+    --no-branch-coverage
+    ${CMAKE_CURRENT_BINARY_DIR}/new.info
+    -o ${CMAKE_CURRENT_BINARY_DIR}/coverage-report
+  DEPENDS doxygen
+  COMMENT "Generating Doxygen coverage info and HTML report..."
+)
+
 #-------------------------------------------------------------------------------
 # devicetree
 

doc/Makefile

@@ -14,7 +14,7 @@ HW_FEATURES_VENDOR_FILTER ?=
 # ------------------------------------------------------------------------------
 # Documentation targets
 
-.PHONY: configure clean html html-fast html-live html-live-fast latex pdf doxygen
+.PHONY: configure clean html html-fast html-live html-live-fast latex pdf doxygen doxygen-coverage
 
 html-fast:
 	${MAKE} html DT_TURBO_MODE=1 HW_FEATURES_TURBO_MODE=1
@@ -22,7 +22,7 @@ html-fast:
 html-live-fast:
 	${MAKE} html-live DT_TURBO_MODE=1 HW_FEATURES_TURBO_MODE=1
 
-html html-live latex pdf linkcheck doxygen: configure
+html html-live latex pdf linkcheck doxygen doxygen-coverage: configure
 	cmake --build ${BUILDDIR} --target $@
 
 configure: