impove compile_commands.json handling

This adds compile_commands.json support for kbuild based packages such as
the Linux kernel and Barebox.

It also adds a make macro that can be used by packages with other
compile_commands.json generators.

Signed-off-by: Michael Olbrich <m.olbrich@pengutronix.de>

4 files changed, 64 insertions, 24 deletions

diff --git a/rules/post/ptxd_make_world_prepare.make b/rules/post/ptxd_make_world_prepare.make
index a91f00b8a..1a0556a84 100644
--- a/rules/post/ptxd_make_world_prepare.make
+++ b/rules/post/ptxd_make_world_prepare.make
@@ -6,6 +6,10 @@
 # see the README file.
 #
 
+world/compile-commands = \
+	$(call world/env, $(1)) \
+	ptxd_make_world_compile_commands $(2)
+
 world/cfghash = \
 	+$(call world/env, $1) \
 	ptxd_make_world_hash cfghash
diff --git a/scripts/lib/ptxd_make_world_compile.sh b/scripts/lib/ptxd_make_world_compile.sh
index d45b138e3..1fb70c7c5 100644
--- a/scripts/lib/ptxd_make_world_compile.sh
+++ b/scripts/lib/ptxd_make_world_compile.sh
@@ -5,6 +5,23 @@
 # see the README file.
 #
 
+ptxd_make_world_compile_finish() {
+    if [ "${pkg_build_tool}" = "kconfig" ]; then
+	if [ -x "${pkg_dir}/scripts/clang-tools/gen_compile_commands.py" ]; then
+	    # fake dependency for python wrapper
+	    pkg_build_deps=host-system-python3 \
+	    "${pkg_dir}/scripts/clang-tools/gen_compile_commands.py" \
+		-d "${pkg_build_dir}" -o "${pkg_build_dir}/compile_commands.json"
+	    if [ $? -ne 0 ]; then
+		ptxd_warning "Ignoring failed scripts/clang-tools/gen_compile_commands.py"
+	    else
+		ptxd_make_world_compile_commands_filter
+	    fi
+	fi
+    fi
+}
+export -f ptxd_make_world_compile_finish
+
 #
 # call the compiler
 #
@@ -66,6 +83,7 @@ ptxd_make_world_compile() {
 	    "${pkg_make_opt}" \
 	    "${pkg_make_par}"
 	;;
-    esac
+    esac &&
+    ptxd_make_world_compile_finish
 }
 export -f ptxd_make_world_compile
diff --git a/scripts/lib/ptxd_make_world_compile_commands.sh b/scripts/lib/ptxd_make_world_compile_commands.sh
new file mode 100644
index 000000000..a3aa2033b
--- /dev/null
+++ b/scripts/lib/ptxd_make_world_compile_commands.sh
@@ -0,0 +1,39 @@
+#!/bin/bash
+#
+# Copyright (C) 2022 by Michael Olbrich <m.olbrich@pengutronix.de>
+#
+# For further information about the PTXdist project and license conditions
+# see the README file.
+#
+
+ptxd_make_world_compile_commands_filter() {
+    local src_cmds="${1:-${pkg_build_dir}/compile_commands.json}"
+    local dst_cmds="${pkg_dir}/compile_commands.json"
+
+    if [ ! -e "${src_cmds}" ]; then
+	ptxd_verbose "Ignoring missing '${src_cmds}'."
+	return
+    fi
+
+    if [ "${src_cmds}" = "${dst_cmds}" ]; then
+	if [ grep -q "${PTXDIST_CROSS_CPPFLAGS}" "${src_cmds}" ]; then
+	    ptxd_warning "compile_commands.json is already up to date!"
+	    return
+	fi
+	mv "${src_cmds}" "${src_cmds}.orig"
+	src_cmds="${src_cmds}.orig"
+    fi
+
+    ptxd_verbose "Generating '$(ptxd_print_path "${dst_cmds}")'"
+    sed \
+	-e "s#\(\"command\": \"[^ ]*\(gcc\|clang\) \)#\1 ${PTXDIST_CROSS_CPPFLAGS} ${pkg_cflags} #" \
+	-e "s#\(\"command\": \"[^ ]*++ \)#\1 ${PTXDIST_CROSS_CPPFLAGS} ${pkg_cxxflags} #" \
+	"${src_cmds}" > "${dst_cmds}"
+}
+export -f ptxd_make_world_compile_commands_filter
+
+ptxd_make_world_compile_commands() {
+    ptxd_make_world_init &&
+    ptxd_make_world_compile_commands_filter
+}
+export -f ptxd_make_world_compile_commands
diff --git a/scripts/lib/ptxd_make_world_prepare.sh b/scripts/lib/ptxd_make_world_prepare.sh
index 538e2bd1b..8ffdd611f 100644
--- a/scripts/lib/ptxd_make_world_prepare.sh
+++ b/scripts/lib/ptxd_make_world_prepare.sh
@@ -69,27 +69,6 @@ EOF
 }
 export -f ptxd_make_world_prepare_sanity_check
 
-ptxd_make_world_prepare_compile_commands() {
-    local src_cmds dst_cmds
-    if [ ! -e compile_commands.json ]; then
-	return
-    fi
-
-    if [ "${pkg_dir}" = "${pkg_build_dir}" ]; then
-	mv compile_commands.json compile_commands.json.orig
-	src_cmds=compile_commands.json.orig
-    else
-	src_cmds=compile_commands.json
-    fi
-    dst_cmds="${pkg_dir}/compile_commands.json"
-
-    sed \
-	-e "s#\(\"command\": \"[^ ]*\(gcc\|clang\) \)#\1 ${PTXDIST_CROSS_CPPFLAGS} ${pkg_cflags} #" \
-	-e "s#\(\"command\": \"[^ ]*++ \)#\1 ${PTXDIST_CROSS_CPPFLAGS} ${pkg_cxxflags} #" \
-	"${src_cmds}" > "${dst_cmds}"
-}
-export -f ptxd_make_world_prepare_compile_commands
-
 #
 # prepare for cmake based pkgs
 #
@@ -102,7 +81,7 @@ ptxd_make_world_prepare_cmake() {
 	cmake \
 	"${pkg_conf_opt}" \
 	"${pkg_conf_dir}" &&
-    ptxd_make_world_prepare_compile_commands
+    ptxd_make_world_compile_commands_filter
 }
 export -f ptxd_make_world_prepare_cmake
 
@@ -173,7 +152,7 @@ ptxd_make_world_prepare_meson() {
 	meson \
 	"${pkg_conf_opt}" \
 	"${pkg_conf_dir}" &&
-    ptxd_make_world_prepare_compile_commands
+    ptxd_make_world_compile_commands_filter
 }
 export -f ptxd_make_world_prepare_meson