libselinux: Add CPPFLAGS to Makefile

Add CPPFLAGS to Makefile to allow users change the flags of
preprocessor.
We offen use CFLAGS for compiler flags and use CPPFLAGS for
preprocessor.

Signed-off-by: Chung-Sheng Wu <[email protected]>

Author: samsam2310

libselinux/src/Makefile

@@ -149,17 +149,17 @@ pywrap: all selinuxswig_python_exception.i
 rubywrap: all $(SWIGRUBYSO)
 
 $(SWIGRUBYLOBJ): $(SWIGRUBYCOUT)
-	$(CC) $(CFLAGS) $(SWIG_CFLAGS) $(RUBYINC) -fPIC -DSHARED -c -o $@ $<
+	$(CC) $(CPPFLAGS) $(CFLAGS) $(SWIG_CFLAGS) $(RUBYINC) -fPIC -DSHARED -c -o $@ $<
 
 $(SWIGRUBYSO): $(SWIGRUBYLOBJ)
-	$(CC) $(CFLAGS) $(LDFLAGS) -L. -shared -o $@ $^ -lselinux $(RUBYLIBS)
+	$(CC) $(CPPFLAGS) $(CFLAGS) $(LDFLAGS) -L. -shared -o $@ $^ -lselinux $(RUBYLIBS)
 
 $(LIBA): $(OBJS)
 	$(AR) rcs $@ $^
 	$(RANLIB) $@
 
 $(LIBSO): $(LOBJS)
-	$(CC) $(CFLAGS) $(LDFLAGS) -shared -o $@ $^ $(PCRE_LDLIBS) $(FTS_LDLIBS) -ldl -Wl,$(LD_SONAME_FLAGS)
+	$(CC) $(CPPFLAGS) $(CFLAGS) $(LDFLAGS) -shared -o $@ $^ $(PCRE_LDLIBS) $(FTS_LDLIBS) -ldl -Wl,$(LD_SONAME_FLAGS)
 	ln -sf $@ $(TARGET)
 
 $(LIBPC): $(LIBPC).in ../VERSION
@@ -169,10 +169,10 @@ selinuxswig_python_exception.i: exception.sh ../include/selinux/selinux.h
 	bash -e exception.sh > $@ || (rm -f $@ ; false)
 
 %.o:  %.c policy.h
-	$(CC) $(CFLAGS) $(TLSFLAGS) -c -o $@ $<
+	$(CC) $(CPPFLAGS) $(CFLAGS) $(TLSFLAGS) -c -o $@ $<
 
 %.lo:  %.c policy.h
-	$(CC) $(CFLAGS) -fPIC -DSHARED -c -o $@ $<
+	$(CC) $(CPPFLAGS) $(CFLAGS) -fPIC -DSHARED -c -o $@ $<
 
 $(SWIGRUBYCOUT): $(SWIGRUBYIF)
 	$(SWIGRUBY) $<