Cirrus: Build multi-arch images + manifests

Github-actions for large/complex tasks is hard to read and maintain.
Reimplement the multi-arch image build workflow into a set of bash
scripts that use all native contrainer-org tooling.  This requires
a special VM image setup with emulation to build foreign architectures.
It also requires renaming the `helloimage` directory, because the build
script uses the directory name in the image FQIN.

Signed-off-by: Chris Evich <cevich@redhat.com>

3 files changed, 114 insertions, 0 deletions

diff --git a/contrib/hello/Containerfile b/contrib/hello/Containerfile
new file mode 100644
index 000000000..0cbf6d9a0
--- /dev/null
+++ b/contrib/hello/Containerfile
@@ -0,0 +1,11 @@
+FROM docker.io/alpine as builder
+RUN apk add gcc libc-dev
+ADD podman_hello_world.c .
+RUN gcc -O2 -static -o podman_hello_world podman_hello_world.c
+
+FROM scratch
+LABEL maintainer="Podman Maintainers"
+LABEL artist="Máirín Ní Ḋuḃṫaiġ, Twitter:@mairin"
+USER 1000
+COPY --from=builder podman_hello_world /usr/local/bin/podman_hello_world
+CMD ["/usr/local/bin/podman_hello_world"]
diff --git a/contrib/hello/README.md b/contrib/hello/README.md
new file mode 100644
index 000000000..528466f7b
--- /dev/null
+++ b/contrib/hello/README.md
@@ -0,0 +1,77 @@
+![PODMAN logo](../../logo/podman-logo-source.svg)
+
+# Podman Hello World image
+
+## Overview
+
+This directory contains the Containerfile and bash script necessary to create the
+"hello" podman image housed on quay.io under the Podman account in a public
+repository.  The image is public and can be pulled without credentials.
+
+Using this image is helpful to:
+
+ * Prove that basic Podman operations are working on the host.
+ * Shows that the image was pulled from the quay.io container registry.
+ * Container creation was successfully accomplished. (`podman ps -a`)
+ * The created container was able to stream output to your terminal.
+
+## Directory Contents
+
+The contents of this directory contain:
+ * ./Containerfile
+ * ./podman_hello_world.c
+
+## Sample Usage
+
+To simply run the image:
+
+```
+podman run quay.io/podman/hello
+
+!... Hello Podman World ...!
+
+         .--"--.
+       / -     - \
+      / (O)   (O) \
+   ~~~| -=(,Y,)=- |
+    .---. /`  \   |~~
+ ~/  o  o \~~~~.----. ~~
+  | =(X)= |~  / (O (O) \
+   ~~~~~~~  ~| =(Y_)=-  |
+  ~~~~    ~~~|   U      |~~
+
+Project:   https://github.com/containers/podman
+Website:   https://podman.io
+Documents: https://docs.podman.io
+Twitter:   @Podman_io
+```
+To build the image yourself, copy the files from this directory into
+a local directory and issue these commands:
+
+```
+podman build -t myhello .
+podman run myhello
+```
+
+## Potential Issues:
+
+The image runs as a rootless user with the UID set to `1000`.
+If the /etc/subuid and /etch/subgid values are not set appropriately to run as a
+rootless user on the host, an error like this might be raised:
+
+```
+Copying blob acab339ca1e8 done
+ERRO[0002] Error while applying layer: ApplyLayer exit status 1 stdout:  stderr: potentially insufficient UIDs or GIDs available in user namespace (requested 0:12 for /var/spool/mail): Check /etc/subuid and /etc/subgid: lchown /var/spool/mail: invalid argument
+Error: writing blob: adding layer with blob "sha256:ee0cde9de8a68f171a8c03b0e9954abf18576947e2f3187e84d8c31ccd8f6a09": ApplyLayer exit status 1 stdout:  stderr: potentially insufficient UIDs or GIDs available in user namespace (requested 0:12 for /var/spool/mail): Check /etc/subuid and /etc/subgid: lchown /var/spool/mail: invalid argument
+```
+
+Please refer to this [blog post](https://www.redhat.com/sysadmin/rootless-podman) for further configuration information.
+
+## THANKS!
+
+Many Thanks to @afbjorklund for a great discussion during the
+first revision of this container image that resulted in moving
+from using bash to using C, and the ensuing changes to the
+Containerfile.
+
+Also many thanks to @mairin for the awesome ASCII art!
diff --git a/contrib/hello/podman_hello_world.c b/contrib/hello/podman_hello_world.c
new file mode 100644
index 000000000..ee574130d
--- /dev/null
+++ b/contrib/hello/podman_hello_world.c
@@ -0,0 +1,26 @@
+//###
+//  ASCII art by the incomparable Máirín Duffy,
+//  duffy@redhat.com, Twitter: @mairin
+//  January 2022
+//###
+
+#include <stdio.h>
+int main() {
+    puts("\
+!... Hello Podman World ...!\n\
+\n\
+         .--\"--.           \n\
+       / -     - \\         \n\
+      / (O)   (O) \\        \n\
+   ~~~| -=(,Y,)=- |         \n\
+    .---. /`  \\   |~~      \n\
+ ~/  o  o \\~~~~.----. ~~   \n\
+  | =(X)= |~  / (O (O) \\   \n\
+   ~~~~~~~  ~| =(Y_)=-  |   \n\
+  ~~~~    ~~~|   U      |~~ \n\
+\n\
+Project:   https://github.com/containers/podman\n\
+Website:   https://podman.io\n\
+Documents: https://docs.podman.io\n\
+Twitter:   @Podman_io");
+}