Towards multi-arch images support

- Add environment variable to allow scripts to make decissions.
- Remove x86 harcoded dependency.
- Disable sqlsrv and oracle drivers for non amd64 builds (they need research).

With these changes it's possible to build both amd64 and arm64 images.

Need this is place to continue testing the new multi-arch
automated builders from GHA (that will replace DockerHub
builds, because, amazingly, they don't support multi-arch yet).

Once built the multi-arch images, we'll be pushing them both
to DockerHub and also to GH own registry.

Dockerfile

@@ -1,5 +1,10 @@
 FROM php:8.0-apache-buster
 
+# So we can use it anywhere for conditional stuff. Keeping BC with old (non-buildkit, builders)
+ARG TARGETPLATFORM
+ENV TARGETPLATFORM=${TARGETPLATFORM:-linux/amd64}
+RUN echo "Building for ${TARGETPLATFORM}"
+
 ADD root/ /
 # Fix the original permissions of /tmp, the PHP default upload tmp dir.
 RUN chmod 777 /tmp && chmod +t /tmp

root/tmp/setup/oci8-extension.sh

@@ -2,6 +2,11 @@
 
 set -e
 
+if [[ ${TARGETPLATFORM} != "linux/amd64" ]]; then
+    echo "oracle extension not available for ${TARGETPLATFORM} architecture, skipping"
+    exit 0
+fi
+
 echo "Downloading oracle files"
 curl https://download.oracle.com/otn_software/linux/instantclient/19600/instantclient-basic-linux.x64-19.6.0.0.0dbru.zip \
     -o /tmp/instantclient-basic-linux.x64-19.6.0.0.0dbru.zip

root/tmp/setup/php-extensions.sh

@@ -60,7 +60,7 @@ docker-php-ext-configure gd --with-freetype=/usr/include/ --with-jpeg=/usr/inclu
 docker-php-ext-install -j$(nproc) gd
 
 # LDAP.
-docker-php-ext-configure ldap --with-libdir=lib/x86_64-linux-gnu/
+docker-php-ext-configure ldap
 docker-php-ext-install -j$(nproc) ldap
 
 # APCu, igbinary, Memcached, MongoDB, Redis, Solr, uuid, XMLRPC (beta)
@@ -72,7 +72,11 @@ echo 'apc.enable_cli = On' >> /usr/local/etc/php/conf.d/docker-php-ext-apcu.ini
 # Install Microsoft dependencies for sqlsrv.
 # (kept apart for clarity, still need to be run here
 # before some build packages are deleted)
-/tmp/setup/sqlsrv-extension.sh
+if [[ ${TARGETPLATFORM} == "linux/amd64" ]]; then
+    /tmp/setup/sqlsrv-extension.sh
+else
+    echo "sqlsrv extension not available for ${TARGETPLATFORM} architecture, skipping"
+fi
 
 # Keep our image size down..
 pecl clear-cache