tools lib api: Add dependency test to install_headers

Compute the headers to be installed from their source headers and make
each have its own build target to install it. Using dependencies
avoids headers being reinstalled and getting a new timestamp which
then causes files that depend on the header to be rebuilt.

Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Josh Poimboeuf <jpoimboe@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Nicolas Schier <nicolas@fjasle.eu>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Rix <trix@redhat.com>
Cc: bpf@vger.kernel.org
Cc: llvm@lists.linux.dev
Link: https://lore.kernel.org/r/20221202045743.2639466-2-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

diff --git a/tools/lib/api/Makefile b/tools/lib/api/Makefile
index 3649c7f..044860a 100644 (file)
--- a/tools/lib/api/Makefile
+++ b/tools/lib/api/Makefile
@@ -88,10 +88,10 @@ define do_install_mkdir
 endef
 
 define do_install
-       if [ ! -d '$(DESTDIR_SQ)$2' ]; then             \
-               $(INSTALL) -d -m 755 '$(DESTDIR_SQ)$2'; \
-       fi;                                             \
-       $(INSTALL) $1 $(if $3,-m $3,) '$(DESTDIR_SQ)$2'
+       if [ ! -d '$2' ]; then             \
+               $(INSTALL) -d -m 755 '$2'; \
+       fi;                                \
+       $(INSTALL) $1 $(if $3,-m $3,) '$2'
 endef
 
 install_lib: $(LIBFILE)
@@ -99,14 +99,28 @@ install_lib: $(LIBFILE)
                $(call do_install_mkdir,$(libdir_SQ)); \
                cp -fpR $(LIBFILE) $(DESTDIR)$(libdir_SQ)
 
-install_headers:
-       $(call QUIET_INSTALL, libapi_headers) \
-               $(call do_install,cpu.h,$(prefix)/include/api,644); \
-               $(call do_install,debug.h,$(prefix)/include/api,644); \
-               $(call do_install,io.h,$(prefix)/include/api,644); \
-               $(call do_install,fd/array.h,$(prefix)/include/api/fd,644); \
-               $(call do_install,fs/fs.h,$(prefix)/include/api/fs,644); \
-               $(call do_install,fs/tracing_path.h,$(prefix)/include/api/fs,644);
+HDRS := cpu.h debug.h io.h
+FD_HDRS := fd/array.h
+FS_HDRS := fs/fs.h fs/tracing_path.h
+INSTALL_HDRS_PFX := $(DESTDIR)$(prefix)/include/api
+INSTALL_HDRS := $(addprefix $(INSTALL_HDRS_PFX)/, $(HDRS))
+INSTALL_FD_HDRS := $(addprefix $(INSTALL_HDRS_PFX)/, $(FD_HDRS))
+INSTALL_FS_HDRS := $(addprefix $(INSTALL_HDRS_PFX)/, $(FS_HDRS))
+
+$(INSTALL_HDRS): $(INSTALL_HDRS_PFX)/%.h: %.h
+       $(call QUIET_INSTALL, $@) \
+               $(call do_install,$<,$(INSTALL_HDRS_PFX)/,644)
+
+$(INSTALL_FD_HDRS): $(INSTALL_HDRS_PFX)/fd/%.h: fd/%.h
+       $(call QUIET_INSTALL, $@) \
+               $(call do_install,$<,$(INSTALL_HDRS_PFX)/fd/,644)
+
+$(INSTALL_FS_HDRS): $(INSTALL_HDRS_PFX)/fs/%.h: fs/%.h
+       $(call QUIET_INSTALL, $@) \
+               $(call do_install,$<,$(INSTALL_HDRS_PFX)/fs/,644)
+
+install_headers: $(INSTALL_HDRS) $(INSTALL_FD_HDRS) $(INSTALL_FS_HDRS)
+       $(call QUIET_INSTALL, libapi_headers)
 
 install: install_lib install_headers