Dockerfile

FROM debian:buster

# prevent Debian's PHP packages from being installed
# https://github.com/docker-library/php/pull/542
RUN set -eux; \
	{ \
		echo 'Package: php*'; \
		echo 'Pin: release *'; \
		echo 'Pin-Priority: -1'; \
	} > /etc/apt/preferences.d/no-debian-php

# dependencies required for running "phpize"
# (see persistent deps below)
ENV PHPIZE_DEPS \
		autoconf \
		dpkg-dev \
		file \
		g++ \
		gcc \
		libc-dev \
		make \
		pkg-config \
		re2c \
        bison

# persistent / runtime deps
RUN set -eux; \
	apt-get update; \
	apt-get install -y --no-install-recommends \
		$PHPIZE_DEPS \
		ca-certificates \
		curl \
		xz-utils \
		time \
	; \
	rm -rf /var/lib/apt/lists/*

# Apply stack smash protection to functions using local buffers and alloca()
# Make PHP's main executable position-independent (improves ASLR security mechanism, and has no performance impact on x86_64)
# Enable optimization (-O2)
# Enable linker optimization (this sorts the hash buckets to improve cache locality, and is non-default)
# https://github.com/docker-library/php/issues/272
# -D_LARGEFILE_SOURCE and -D_FILE_OFFSET_BITS=64 (https://www.php.net/manual/en/intro.filesystem.php)
ENV PHP_CFLAGS="-fstack-protector-strong -fpic -fpie -O2 -D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64"
ENV PHP_CPPFLAGS="$PHP_CFLAGS"
ENV PHP_LDFLAGS="-Wl,-O1 -pie"

RUN set -eux; \
	\
	savedAptMark="$(apt-mark showmanual)"; \
	apt-get update; \
	apt-get install -y --no-install-recommends dirmngr; \
	rm -rf /var/lib/apt/lists/*; \
	\
	apt-mark auto '.*' > /dev/null; \
	apt-mark manual $savedAptMark > /dev/null; \
	apt-get purge -y --auto-remove -o APT::AutoRemove::RecommendsImportant=false

COPY . /usr/src/php
ENV PHP_INI_DIR /usr/local/etc/php

RUN set -eux; \
	mkdir -p "$PHP_INI_DIR/conf.d"; \
# allow running as an arbitrary user (https://github.com/docker-library/php/issues/743)
	[ ! -d /var/www/html ]; \
	mkdir -p /var/www/html; \
	chown www-data:www-data /var/www/html; \
	chmod 777 /var/www/html

RUN set -eux; \
	\
	savedAptMark="$(apt-mark showmanual)"; \
	apt-get update; \
	apt-get install -y --no-install-recommends \
		libcurl4-openssl-dev \
		libedit-dev \
		libonig-dev \
		libsqlite3-dev \
		libssl-dev \
		libxml2-dev \
		zlib1g-dev \
	; \
	rm -rf /var/lib/apt/lists/*; \
	\
	export \
		CFLAGS="$PHP_CFLAGS" \
		CPPFLAGS="$PHP_CPPFLAGS" \
		LDFLAGS="$PHP_LDFLAGS" \
	; \
	gnuArch="$(dpkg-architecture --query DEB_BUILD_GNU_TYPE)"; \
	debMultiarch="$(dpkg-architecture --query DEB_BUILD_MULTIARCH)"; \
# https://bugs.php.net/bug.php?id=74125
	if [ ! -d /usr/include/curl ]; then \
		ln -sT "/usr/include/$debMultiarch/curl" /usr/local/include/curl; \
	fi; \
	cd /usr/src/php; \
    ./buildconf; \
	./configure \
		--build="$gnuArch" \
		--with-config-file-path="$PHP_INI_DIR" \
		--with-config-file-scan-dir="$PHP_INI_DIR/conf.d" \
		\
# make sure invalid --configure-flags are fatal errors instead of just warnings
		--enable-option-checking=fatal \
		--enable-mbstring \
# --enable-mysqlnd is included here because it's harder to compile after the fact than extensions are (since it's a plugin for several extensions, not an extension in itself)
		--enable-mysqlnd \
		--enable-opcache \
# always build against system sqlite3 (https://github.com/php/php-src/commit/6083a387a81dbbd66d6316a3a12a63f06d5f7109)
		--with-pdo-sqlite=/usr \
		\
		--with-curl \
		--with-openssl \
		\
# bundled pcre does not support JIT on s390x
# https://manpages.debian.org/stretch/libpcre3-dev/pcrejit.3.en.html#AVAILABILITY_OF_JIT_SUPPORT
		$(test "$gnuArch" = 's390x-linux-gnu' && echo '--without-pcre-jit') \
		--with-libdir="lib/$debMultiarch" \
        \
        --enable-cgi \
	; \
	make -j "$(nproc)"; \
	find -type f -name '*.a' -delete; \
	find -type f -name '*.dep' -delete; \
	make install; \
	find /usr/local/bin /usr/local/sbin -type f -executable -exec strip --strip-all '{}' + || true; \
	make clean; \
	\
# https://github.com/docker-library/php/issues/692 (copy default example "php.ini" files somewhere easily discoverable)
	cp -v php.ini-* "$PHP_INI_DIR/"; \
	\
# reset apt-mark's "manual" list so that "purge --auto-remove" will remove all build dependencies
	apt-mark auto '.*' > /dev/null; \
	[ -z "$savedAptMark" ] || apt-mark manual $savedAptMark; \
	find /usr/local -type f -executable -exec ldd '{}' ';' \
		| awk '/=>/ { print $(NF-1) }' \
		| sort -u \
		| xargs -r dpkg-query --search \
		| cut -d: -f1 \
		| sort -u \
		| xargs -r apt-mark manual \
	; \
	apt-get purge -y --auto-remove -o APT::AutoRemove::RecommendsImportant=false; \
	\
# smoke test
	php --version

# temporary "freetype-config" workaround for https://github.com/docker-library/php/issues/865 (https://bugs.php.net/bug.php?id=76324)
RUN { echo '#!/bin/sh'; echo 'exec pkg-config "$@" freetype2'; } > /usr/local/bin/freetype-config && chmod +x /usr/local/bin/freetype-config

CMD ["php-cgi"]