tests/docker: add a docker-exec-copy-test

This provides test machinery for checking the QEMU copying logic works
properly. It takes considerably less time to run than starting a
debootstrap only for it to fail later. I considered adding a remove
command to docker.py but figured that might be gold plating given the
relative size of the containers compared to the ones with actual stuff
in them.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20210202134001.25738-7-alex.bennee@linaro.org>

tests/docker/Makefile.include

@@ -11,7 +11,7 @@ HOST_ARCH = $(if $(ARCH),$(ARCH),$(shell uname -m))
 DOCKER_SUFFIX := .docker
 DOCKER_FILES_DIR := $(SRC_PATH)/tests/docker/dockerfiles
 # we don't run tests on intermediate images (used as base by another image)
-DOCKER_PARTIAL_IMAGES := debian10 debian11 debian-bootstrap
+DOCKER_PARTIAL_IMAGES := debian10 debian11 debian-bootstrap empty
 DOCKER_IMAGES := $(sort $(notdir $(basename $(wildcard $(DOCKER_FILES_DIR)/*.docker))))
 DOCKER_TARGETS := $(patsubst %,docker-image-%,$(DOCKER_IMAGES))
 # Use a global constant ccache directory to speed up repetitive builds
@@ -92,6 +92,24 @@ docker-binfmt-image-debian-%: $(DOCKER_FILES_DIR)/debian-bootstrap.docker
 			{ echo "You will need to build $(EXECUTABLE)"; exit 1;},\
 			"CHECK", "debian-$* exists"))
 
+# These are test targets
+USER_TCG_TARGETS=$(patsubst %-linux-user,qemu-%,$(filter %-linux-user,$(TARGET_DIRS)))
+EXEC_COPY_TESTS=$(patsubst %,docker-exec-copy-test-%, $(USER_TCG_TARGETS))
+
+$(EXEC_COPY_TESTS): docker-exec-copy-test-%: $(DOCKER_FILES_DIR)/empty.docker
+	$(call quiet-command,							\
+		$(DOCKER_SCRIPT) build -t qemu/exec-copy-test-$* -f $< 		\
+			$(if $V,,--quiet) --no-cache 				\
+			--include-executable=$*					\
+			--skip-binfmt,						\
+			"TEST","copy $* to container")
+	$(call quiet-command,							\
+		$(DOCKER_SCRIPT) run qemu/exec-copy-test-$* 			\
+			/$* -version > tests/docker-exec-copy-test-$*.out,	\
+			"TEST","check $* works in container")
+
+docker-exec-copy-test: $(EXEC_COPY_TESTS)
+
 endif
 
 # Enforce dependencies for composite images

tests/docker/docker.py

@@ -438,6 +438,9 @@ class BuildCommand(SubCommand):
                             help="""Specify a binary that will be copied to the
                             container together with all its dependent
                             libraries""")
+        parser.add_argument("--skip-binfmt",
+                            action="store_true",
+                            help="""Skip binfmt entry check (used for testing)""")
         parser.add_argument("--extra-files", nargs='*',
                             help="""Specify files that will be copied in the
                             Docker image, fulfilling the ADD directive from the
@@ -466,7 +469,9 @@ class BuildCommand(SubCommand):
             docker_dir = tempfile.mkdtemp(prefix="docker_build")
 
             # Validate binfmt_misc will work
-            if args.include_executable:
+            if args.skip_binfmt:
+                qpath = args.include_executable
+            elif args.include_executable:
                 qpath, enabled = _check_binfmt_misc(args.include_executable)
                 if not enabled:
                     return 1

tests/docker/dockerfiles/empty.docker

@@ -0,0 +1,8 @@
+#
+# Empty Dockerfile
+#
+
+FROM scratch
+
+# Add everything from the context into the container
+ADD . /