Allow for ergnomically putting Unix-only files in subdirs by creating INLCUDE_$(pkg) vars

Separate platform-specific files will allow avoiding a lot of CPP.

src/libcmd/local.mk

@@ -6,7 +6,7 @@ libcmd_DIR := $(d)
 
 libcmd_SOURCES := $(wildcard $(d)/*.cc)
 
-libcmd_CXXFLAGS += -I src/libutil -I src/libstore -I src/libexpr -I src/libmain -I src/libfetchers
+libcmd_CXXFLAGS += $(INCLUDE_libutil) $(INCLUDE_libstore) $(INCLUDE_libfetchers) $(INCLUDE_libexpr) -I src/libmain
 
 libcmd_LDFLAGS = $(EDITLINE_LIBS) $(LOWDOWN_LIBS) $(THREAD_LDFLAGS)
 

src/libexpr/local.mk

@@ -11,8 +11,11 @@ libexpr_SOURCES := \
   $(wildcard $(d)/flake/*.cc) \
   $(d)/lexer-tab.cc \
   $(d)/parser-tab.cc
+# Not just for this library itself, but also for downstream libraries using this library
 
-libexpr_CXXFLAGS += -I src/libutil -I src/libstore -I src/libfetchers -I src/libmain -I src/libexpr
+INCLUDE_libexpr := -I $(d)
+
+libexpr_CXXFLAGS += $(INCLUDE_libutil) $(INCLUDE_libstore) $(INCLUDE_libfetchers) -I src/libmain $(INCLUDE_libexpr)
 
 libexpr_LIBS = libutil libstore libfetchers
 

src/libfetchers/local.mk

@@ -6,7 +6,11 @@ libfetchers_DIR := $(d)
 
 libfetchers_SOURCES := $(wildcard $(d)/*.cc)
 
-libfetchers_CXXFLAGS += -I src/libutil -I src/libstore
+# Not just for this library itself, but also for downstream libraries using this library
+
+INCLUDE_libfetchers := -I $(d)
+
+libfetchers_CXXFLAGS += $(INCLUDE_libutil) $(INCLUDE_libstore) $(INCLUDE_libfetchers)
 
 libfetchers_LDFLAGS += $(THREAD_LDFLAGS) $(LIBGIT2_LIBS) -larchive
 

src/libmain/local.mk

@@ -6,7 +6,7 @@ libmain_DIR := $(d)
 
 libmain_SOURCES := $(wildcard $(d)/*.cc)
 
-libmain_CXXFLAGS += -I src/libutil -I src/libstore
+libmain_CXXFLAGS += $(INCLUDE_libutil) $(INCLUDE_libstore)
 
 libmain_LDFLAGS += $(OPENSSL_LIBS)
 

src/libstore/local.mk

@@ -10,7 +10,7 @@ libstore_LIBS = libutil
 
 libstore_LDFLAGS += $(SQLITE3_LIBS) $(LIBCURL_LIBS) $(THREAD_LDFLAGS)
 ifdef HOST_LINUX
- libstore_LDFLAGS += -ldl
+  libstore_LDFLAGS += -ldl
 endif
 
 $(foreach file,$(libstore_FILES),$(eval $(call install-data-in,$(d)/$(file),$(datadir)/nix/sandbox)))
@@ -27,8 +27,12 @@ ifeq ($(HAVE_SECCOMP), 1)
   libstore_LDFLAGS += $(LIBSECCOMP_LIBS)
 endif
 
+# Not just for this library itself, but also for downstream libraries using this library
+
+INCLUDE_libstore := -I $(d) -I $(d)/build
+
 libstore_CXXFLAGS += \
- -I src/libutil -I src/libstore -I src/libstore/build \
+ $(INCLUDE_libutil) $(INCLUDE_libstore) $(INCLUDE_libstore) \
  -DNIX_PREFIX=\"$(prefix)\" \
  -DNIX_STORE_DIR=\"$(storedir)\" \
  -DNIX_DATA_DIR=\"$(datadir)\" \

src/libutil/local.mk

@@ -6,7 +6,10 @@ libutil_DIR := $(d)
 
 libutil_SOURCES := $(wildcard $(d)/*.cc $(d)/signature/*.cc)
 
-libutil_CXXFLAGS += -I src/libutil
+# Not just for this library itself, but also for downstream libraries using this library
+
+INCLUDE_libutil := -I $(d)
+libutil_CXXFLAGS += $(INCLUDE_libutil)
 
 libutil_LDFLAGS += $(THREAD_LDFLAGS) $(LIBCURL_LIBS) $(SODIUM_LIBS) $(OPENSSL_LIBS) $(LIBBROTLI_LIBS) $(LIBARCHIVE_LIBS) $(BOOST_LDFLAGS) -lboost_context
 

src/nix/local.mk

@@ -14,7 +14,7 @@ nix_SOURCES := \
   $(wildcard src/nix-instantiate/*.cc) \
   $(wildcard src/nix-store/*.cc) \
 
-nix_CXXFLAGS += -I src/libutil -I src/libstore -I src/libfetchers -I src/libexpr -I src/libmain -I src/libcmd -I doc/manual
+nix_CXXFLAGS += $(INCLUDE_libutil) $(INCLUDE_libstore) $(INCLUDE_libfetchers) $(INCLUDE_libexpr) -I src/libmain -I src/libcmd -I doc/manual
 
 nix_LIBS = libexpr libmain libfetchers libstore libutil libcmd
 

src/resolve-system-dependencies/local.mk

@@ -6,7 +6,7 @@ resolve-system-dependencies_DIR := $(d)
 
 resolve-system-dependencies_INSTALL_DIR := $(libexecdir)/nix
 
-resolve-system-dependencies_CXXFLAGS += -I src/libutil -I src/libstore -I src/libmain
+resolve-system-dependencies_CXXFLAGS += $(INCLUDE_libutil) $(INCLUDE_libstore) -I src/libmain
 
 resolve-system-dependencies_LIBS := libstore libmain libutil