test: add busybox image, use it to mostly replace centos image

This is basically the add of BUSYBOX image and then using
that instead of centos image.

Moving to busybox from centos required a few changed assumptions:

 * drop -P from grep - busybox's grep did not support -P. instead
   use posix groups ([:space:])
 * don't use long --format for 'stat' - busybox stat didn't like
   this, so just use '-c'.
 * mount - /usr/bin/mount -> /bin/mount - busybox image only has
   /bin, not /usr/bin/mount
 * /bin/bash - busybox image does not have bin/bash

The tests "squashfs empty change no layer" and
"tar empty change no layer" do not work with the busybox image.
There are layers created, and they have this content:

    $ tar tvf oci/blobs/sha256/acff571f8cf*b03f45
    tar: Removing leading `/' from member names
    drwxr-xr-x 0/0               0 2023-11-13 14:06 /
    drwxr-xr-x 0/0               0 2023-11-13 14:06 etc/
    ---------- 0/0               0 2023-11-13 14:06 etc/resolv.conf
    drwxr-xr-x 0/0               0 2023-11-13 14:06 proc/
    drwxr-xr-x 0/0               0 2023-11-13 14:06 sys/

The content there are results of stacker.  I don't have a good way
to avoid them at the moment.

I've also left the bom tests in place with the centos image.
Those would have had to have been adjusted and probably
would not work with busybox at the moment.

Signed-off-by: Scott Moser <[email protected]>

Makefile

@@ -20,9 +20,15 @@ build_stacker = go build -tags "$(BUILD_TAGS) $1" -ldflags "-X main.version=$(VE
 STACKER_DOCKER_BASE?=docker://ghcr.io/project-stacker/
 # They default to their image name in STACKER_DOCKER_BASE
 STACKER_BUILD_BASE_IMAGE?=$(STACKER_DOCKER_BASE)alpine:edge
+STACKER_BUILD_BUSYBOX_IMAGE?=$(STACKER_DOCKER_BASE)busybox:latest
 STACKER_BUILD_CENTOS_IMAGE?=$(STACKER_DOCKER_BASE)centos:latest
 STACKER_BUILD_UBUNTU_IMAGE?=$(STACKER_DOCKER_BASE)ubuntu:latest
-STACKER_BUILD_IMAGES = $(STACKER_BUILD_BASE_IMAGE) $(STACKER_BUILD_CENTOS_IMAGE) $(STACKER_BUILD_UBUNTU_IMAGE)
+STACKER_BUILD_IMAGES = \
+	$(STACKER_BUILD_BASE_IMAGE) \
+	$(STACKER_BUILD_BUSYBOX_IMAGE) \
+	$(STACKER_BUILD_CENTOS_IMAGE) \
+	$(STACKER_BUILD_UBUNTU_IMAGE)
+
 LXC_CLONE_URL?=https://github.com/lxc/lxc
 LXC_BRANCH?=stable-5.0
 
@@ -128,6 +134,7 @@ test: stacker $(REGCLIENT) $(SKOPEO) $(ZOT)
 		LXC_BRANCH=$(LXC_BRANCH) \
 		LXC_CLONE_URL=$(LXC_CLONE_URL) \
 		STACKER_BUILD_BASE_IMAGE=$(STACKER_BUILD_BASE_IMAGE) \
+		STACKER_BUILD_BUSYBOX_IMAGE=$(STACKER_BUILD_BUSYBOX_IMAGE) \
 		STACKER_BUILD_CENTOS_IMAGE=$(STACKER_BUILD_CENTOS_IMAGE) \
 		STACKER_BUILD_UBUNTU_IMAGE=$(STACKER_BUILD_UBUNTU_IMAGE) \
 		./test/main.py \

test/annotations-namespace.bats

@@ -13,7 +13,7 @@ function teardown() {
 thing:
     from:
         type: oci
-        url: $CENTOS_OCI
+        url: $BUSYBOX_OCI
     run: ls
 EOF
     stacker build --annotations-namespace=namespace.example
@@ -28,7 +28,7 @@ EOF
 thing:
     from:
         type: oci
-        url: $CENTOS_OCI
+        url: $BUSYBOX_OCI
     run: ls
 EOF
     stacker build

test/annotations.bats

@@ -13,7 +13,7 @@ function teardown() {
 thing:
     from:
         type: oci
-        url: $CENTOS_OCI
+        url: $BUSYBOX_OCI
     run: ls
     annotations:
       a.b.c.key: val

test/args.bats

@@ -13,7 +13,7 @@ function teardown() {
 parent:
     from:
         type: oci
-        url: $CENTOS_OCI
+        url: $BUSYBOX_OCI
 child:
     from:
         type: built

test/asterisk.bats

@@ -13,7 +13,7 @@ function teardown() {
 a:
     from:
         type: oci
-        url: $CENTOS_OCI
+        url: $BUSYBOX_OCI
     run: |
         mkdir /mybin
         cp /bin/* /mybin

test/atomfs.bats

@@ -16,7 +16,7 @@ function basic_test() {
 test:
     from:
         type: oci
-        url: $CENTOS_OCI
+        url: $BUSYBOX_OCI
     run: |
         touch /hello
 EOF
@@ -48,7 +48,7 @@ EOF
 base:
     from:
         type: oci
-        url: $CENTOS_OCI
+        url: $BUSYBOX_OCI
     run: touch /base
 a:
     from:
@@ -105,7 +105,7 @@ EOF
 
     # c should still be ok
     [ -f c/c ]
-    [ -f c/sbin/init ]
+    [ -f c/bin/sh ]
     stacker internal-go atomfs umount c
 
     # c's last layer shouldn't exist any more, since it is unique
@@ -121,7 +121,7 @@ EOF
 test:
     from:
         type: oci
-        url: $CENTOS_OCI
+        url: $BUSYBOX_OCI
     run: |
         touch /hello
 EOF

test/basic.bats

@@ -10,10 +10,10 @@ function teardown() {
 
 @test "multiple stacker builds in a row" {
     cat > stacker.yaml <<EOF
-centos:
+busybox:
     from:
         type: oci
-        url: $CENTOS_OCI
+        url: $BUSYBOX_OCI
     import: import
 EOF
     echo 1 > import
@@ -28,10 +28,10 @@ EOF
 
 @test "basic workings" {
     cat > stacker.yaml <<EOF
-centos:
+busybox:
     from:
         type: tar
-        url: .stacker/layer-bases/centos.tar
+        url: .stacker/layer-bases/busybox.tar
     import:
         - ./stacker.yaml
         - https://www.cisco.com/favicon.ico
@@ -53,7 +53,7 @@ centos:
 layer1:
     from:
         type: built
-        tag: centos
+        tag: busybox
     run:
         - rm /favicon.ico
 EOF
@@ -62,29 +62,29 @@ EOF
     chmod +x executable
     mkdir -p .stacker/layer-bases
     chmod 777 .stacker/layer-bases
-    image_copy oci:$CENTOS_OCI oci:.stacker/layer-bases/oci:centos
-    umoci unpack --image .stacker/layer-bases/oci:centos dest
-    tar caf .stacker/layer-bases/centos.tar -C dest/rootfs .
+    image_copy oci:$BUSYBOX_OCI oci:.stacker/layer-bases/oci:busybox
+    umoci unpack --image .stacker/layer-bases/oci:busybox dest
+    tar caf .stacker/layer-bases/busybox.tar -C dest/rootfs .
     rm -rf dest
 
     stacker build --substitute "FAVICON=favicon.ico"
     [ "$status" -eq 0 ]
 
     # did we really download the image to the right place?
-    [ -f .stacker/layer-bases/centos.tar ]
+    [ -f .stacker/layer-bases/busybox.tar ]
 
     # did run actually copy the favicon to the right place?
-    stacker grab centos:/favicon.ico
-    [ "$(sha .stacker/imports/centos/favicon.ico)" == "$(sha favicon.ico)" ]
+    stacker grab busybox:/favicon.ico
+    [ "$(sha .stacker/imports/busybox/favicon.ico)" == "$(sha favicon.ico)" ]
 
     [ ! -f roots/layer1/rootfs/favicon.ico ] || [ ! -f roots/layer1/overlay/favicon.ico ]
 
     rm executable
-    stacker grab centos:/usr/bin/executable
+    stacker grab busybox:/usr/bin/executable
     [ "$(stat --format="%a" executable)" = "755" ]
 
     # did we do a copy correctly?
-    [ "$(sha .stacker/imports/centos/stacker.yaml)" == "$(sha ./stacker.yaml)" ]
+    [ "$(sha .stacker/imports/busybox/stacker.yaml)" == "$(sha ./stacker.yaml)" ]
 
     # check OCI image generation
     manifest=$(cat oci/index.json | jq -r .manifests[0].digest | cut -f2 -d:)
@@ -140,15 +140,15 @@ EOF
 
 @test "stacker.yaml without imports can run" {
     cat > stacker.yaml <<EOF
-centos:
+busybox:
     from:
         type: oci
-        url: $CENTOS_OCI
+        url: $BUSYBOX_OCI
     run: |
         touch /foo
 EOF
     stacker build
-    umoci unpack --image oci:centos dest
+    umoci unpack --image oci:busybox dest
     [ -f dest/rootfs/foo ]
 }
 
@@ -162,25 +162,25 @@ EOF
 @test "use colons in roots-dir path name should fail" {
     local tmpd=$(pwd)
     cat > stacker.yaml <<EOF
-centos:
+busybox:
     from:
         type: oci
-        url: $CENTOS_OCI
+        url: $BUSYBOX_OCI
     run: |
         touch /foo
 EOF
     bad_stacker --roots-dir $tmpd/with:colon build
     [ "$status" -eq 1 ]
     echo $output | grep "forbidden"
-} 
+}
 
 @test "use colons in layer name should fail" {
     local tmpd=$(pwd)
     cat > stacker.yaml <<EOF
-centos:with:colon:
+busybox:with:colon:
     from:
         type: oci
-        url: $CENTOS_OCI
+        url: $BUSYBOX_OCI
     run: |
         touch /foo
 EOF
@@ -194,10 +194,10 @@ EOF
     FAVICON: favicon.ico
 EOF
     cat > stacker.yaml <<EOF
-centos:
+busybox:
     from:
         type: tar
-        url: .stacker/layer-bases/centos.tar
+        url: .stacker/layer-bases/busybox.tar
     import:
         - ./stacker.yaml
         - https://www.cisco.com/favicon.ico
@@ -219,7 +219,7 @@ centos:
 layer1:
     from:
         type: built
-        tag: centos
+        tag: busybox
     run:
         - rm /favicon.ico
 EOF
@@ -228,29 +228,29 @@ EOF
     chmod +x executable
     mkdir -p .stacker/layer-bases
     chmod 777 .stacker/layer-bases
-    image_copy oci:$CENTOS_OCI oci:.stacker/layer-bases/oci:centos
-    umoci unpack --image .stacker/layer-bases/oci:centos dest
-    tar caf .stacker/layer-bases/centos.tar -C dest/rootfs .
+    image_copy oci:$BUSYBOX_OCI oci:.stacker/layer-bases/oci:busybox
+    umoci unpack --image .stacker/layer-bases/oci:busybox dest
+    tar caf .stacker/layer-bases/busybox.tar -C dest/rootfs .
     rm -rf dest
 
     stacker build --substitute-file subs.yaml
     [ "$status" -eq 0 ]
 
     # did we really download the image to the right place?
-    [ -f .stacker/layer-bases/centos.tar ]
+    [ -f .stacker/layer-bases/busybox.tar ]
 
     # did run actually copy the favicon to the right place?
-    stacker grab centos:/favicon.ico
-    [ "$(sha .stacker/imports/centos/favicon.ico)" == "$(sha favicon.ico)" ]
+    stacker grab busybox:/favicon.ico
+    [ "$(sha .stacker/imports/busybox/favicon.ico)" == "$(sha favicon.ico)" ]
 
     [ ! -f roots/layer1/rootfs/favicon.ico ] || [ ! -f roots/layer1/overlay/favicon.ico ]
 
     rm executable
-    stacker grab centos:/usr/bin/executable
+    stacker grab busybox:/usr/bin/executable
     [ "$(stat --format="%a" executable)" = "755" ]
 
     # did we do a copy correctly?
-    [ "$(sha .stacker/imports/centos/stacker.yaml)" == "$(sha ./stacker.yaml)" ]
+    [ "$(sha .stacker/imports/busybox/stacker.yaml)" == "$(sha ./stacker.yaml)" ]
 
     # check OCI image generation
     manifest=$(cat oci/index.json | jq -r .manifests[0].digest | cut -f2 -d:)

test/binds.bats

@@ -13,7 +13,7 @@ function teardown() {
 bind-test:
     from:
         type: oci
-        url: ${{CENTOS_OCI}}
+        url: ${{BUSYBOX_OCI}}
     binds:
         - ${{bind_path}} -> /root/tree1/foo
     run: |
@@ -29,7 +29,7 @@ EOF
 
     bind_path=$(realpath tree1/foo)
 
-    out=$(stacker build --substitute bind_path=${bind_path} --substitute CENTOS_OCI=$CENTOS_OCI)
+    out=$(stacker build --substitute bind_path=${bind_path} --substitute BUSYBOX_OCI=$BUSYBOX_OCI)
 
     [[ "${out}" =~ ^(.*filesystem bind-test built successfully)$ ]]
 
@@ -41,7 +41,7 @@ EOF
 bind-test:
     from:
         type: oci
-        url: ${{CENTOS_OCI}}
+        url: ${{BUSYBOX_OCI}}
     binds:
         - source: ${{bind_path1}}
           dest: /root/tree1/foo
@@ -65,7 +65,7 @@ EOF
     out=$(stacker build \
         "--substitute=bind_path1=${bind_path1}" \
         "--substitute=bind_path2=${bind_path2}" \
-        "--substitute=CENTOS_OCI=$CENTOS_OCI" ) || {
+        "--substitute=BUSYBOX_OCI=$BUSYBOX_OCI" ) || {
              printf "%s\n" "$out" 1>&2
              exit 1
         }

test/broken-link.bats

@@ -14,7 +14,7 @@ function teardown() {
 broken_link:
     from:
         type: oci
-        url: $CENTOS_OCI
+        url: $BUSYBOX_OCI
     import:
         - dir
     run: cp -a /stacker/imports/dir/testln /testln