*: ensure make apparmor_parser is cached

This change updates parser/Makefile to respect target dependencies and
not rebuild apparmor_parser if nothing's changed. The goal is to allow
cross-compiled tests #17 to run on a target system without the tests
attempting to rebuild the parser.

Two changes were made:

* Generate af_names.h in a script so the script timestamp is compared.
* Use FORCE instead of PHONY for libapparmor_re/libapparmor_re.a

Changes to list_af_names are intended to exactly replicate the old
behavior.

Signed-off-by: Eric Chiang <ericchiang@google.com>

common/Make.rules

@@ -87,27 +87,6 @@ CAPABILITIES=$(shell echo "\#include <linux/capability.h>" | cpp -dM | LC_ALL=C
 list_capabilities: /usr/include/linux/capability.h
 	@echo "$(CAPABILITIES)"
 
-# =====================
-# generate list of network protocols based on
-# sys/socket.h for use in multiple locations in
-# the source tree
-# =====================
-
-# These are the families that it doesn't make sense for apparmor
-# to mediate. We use PF_ here since that is what is required in
-# bits/socket.h, but we will rewrite these as AF_.
-
-FILTER_FAMILIES=PF_UNIX
-
-__FILTER=$(shell echo $(strip $(FILTER_FAMILIES)) | sed -e 's/ /\\\|/g')
-
-# emits the AF names in a "AF_NAME NUMBER," pattern
-AF_NAMES=$(shell echo "\#include <sys/socket.h>" | cpp -dM | LC_ALL=C sed -n -e '/$(__FILTER)/d' -e 's/PF_LOCAL/PF_UNIX/' -e 's/^\#define[ \t]\+PF_\([A-Z0-9_]\+\)[ \t]\+\([0-9]\+\).*$$/AF_\1 \2,/p' | sort -n -k2)
-
-.PHONY: list_af_names
-list_af_names:
-	@echo "$(AF_NAMES)"
-
 # =====================
 # manpages
 # =====================

common/list_af_names.sh

@@ -0,0 +1,19 @@
+#!/bin/bash -e
+
+# =====================
+# generate list of network protocols based on
+# sys/socket.h for use in multiple locations in
+# the source tree
+# =====================
+
+# It doesn't make sence for AppArmor to mediate PF_UNIX, filter it out. Search
+# for "PF_" constants since that is what is required in bits/socket.h, but
+# rewrite as "AF_".
+
+echo "#include <sys/socket.h>" | \
+  cpp -dM | \
+  LC_ALL=C sed -n \
+    -e '/PF_UNIX/d' \
+    -e 's/PF_LOCAL/PF_UNIX/' \
+    -e 's/^#define[ \t]\+PF_\([A-Z0-9_]\+\)[ \t]\+\([0-9]\+\).*$/AF_\1 \2,/p' | \
+  sort -n -k2

parser/Makefile

@@ -278,10 +278,9 @@ parser_version.h: Makefile
 # as well as the filtering that occurs for network protocols that
 # apparmor should not mediate.
 
-.PHONY: af_names.h
-af_names.h:
-	echo "$(AF_NAMES)" | LC_ALL=C sed -n -e 's/[ \t]\?AF_MAX[ \t]\+[0-9]\+,//g'  -e 's/[ \t]\+\?AF_\([A-Z0-9_]\+\)[ \t]\+\([0-9]\+\),/#ifndef AF_\1\n#  define AF_\1 \2\n#endif\nAA_GEN_NET_ENT("\L\1", \UAF_\1)\n\n/pg' > $@
-	echo "$(AF_NAMES)" | LC_ALL=C sed -n -e 's/.*,[ \t]\+AF_MAX[ \t]\+\([0-9]\+\),\?.*/#define AA_AF_MAX \1\n/p' >> $@
+af_names.h: ../common/list_af_names.sh
+	../common/list_af_names.sh | LC_ALL=C sed -n -e 's/[ \t]\?AF_MAX[ \t]\+[0-9]\+,//g'  -e 's/[ \t]\+\?AF_\([A-Z0-9_]\+\)[ \t]\+\([0-9]\+\),/#ifndef AF_\1\n#  define AF_\1 \2\n#endif\nAA_GEN_NET_ENT("\L\1", \UAF_\1)\n/pg' > $@
+	../common/list_af_names.sh | LC_ALL=C sed -n -e 's/AF_MAX[ \t]\+\([0-9]\+\),\?.*/\n#define AA_AF_MAX \1\n/p' >> $@
 	# cat $@
 
 cap_names.h: /usr/include/linux/capability.h
@@ -301,10 +300,7 @@ tests: apparmor_parser ${TESTS}
 	sh -e -c 'for test in ${TESTS} ; do echo "*** running $${test}" && ./$${test}; done'
 	$(Q)$(MAKE) -s -C tst tests
 
-# always need to rebuild.
-.SILENT: $(AAREOBJECT)
-.PHONY: $(AAREOBJECT)
-$(AAREOBJECT):
+$(AAREOBJECT): FORCE
 	$(MAKE) -C $(AAREDIR) CFLAGS="$(EXTRA_CXXFLAGS)"
 
 .PHONY: install-rhel4
@@ -404,3 +400,4 @@ clean: pod_clean
 	$(MAKE) -s -C po clean
 	$(MAKE) -s -C tst clean
 
+FORCE:

utils/vim/create-apparmor.vim.py

@@ -57,7 +57,7 @@ for cap in capabilities:
         benign_caps.append(cap)
 
 # get network protos list
-(rc, output) = cmd(['make', '-s', '--no-print-directory', 'list_af_names'])
+(rc, output) = cmd(['../../common/list_af_names.sh'])
 if rc != 0:
     sys.stderr.write("make list_af_names failed: " + output)
     exit(rc)