mpx.env.example

# optional arbitrary shell, sourced from /etc/mpx.env into every single
# add.sh/del.sh invocation, right before it runs.
#
# unlike mpx.conf (a fixed KEY="value" grammar, parsed by mpx itself, with
# a specific known set of keys), this file is not parsed at all -- it's
# sourced as real shell into the same wrapper shell that then execs the
# phase script, so it can do anything a shell script can: export an
# arbitrary env var no mpx.conf key covers, run a command, set up
# something the whole build tree relies on, whatever a specific site needs
# that isn't one of mpx.conf's own TARGET_*/JOBS/SANDBOX keys.
#
# absent entirely (the common case, and the default -- this file does not
# exist until you copy this example to /etc/mpx.env yourself) is a silent
# no-op: nothing about a build changes. present, it always runs, for every
# port, every phase -- there is no per-package section built into ITS OWN
# grammar the way mpx.conf has (this file has no grammar at all, just
# plain shell), but see this file's own mpx.env.d/ convention further
# down for a way to get the same effect anyway.
#
# it runs under "set -e" (same as every add.sh/del.sh): a failing command
# in here aborts the phase loudly, the same "fail loud, not silent" rule
# as everywhere else in mpx -- so keep it simple, and don't put anything
# in here you wouldn't want to block every single build if it broke.
#
# example: export a var every add.sh/del.sh script can rely on being set,
# without adding a new mpx.conf key just for it:
#
#export MY_SITE_MIRROR="https://mirror.example.internal"
 
# example: make sure a tool every build needs is on PATH, without relying
# on whatever PATH mpx happened to inherit from whoever invoked it:
#
#PATH="/opt/local-toolchain/bin:$PATH"
#export PATH
 
# per-package override files: mpx.conf has a real per-package "<name>:"
# section built into its own KEY="value" grammar; this file has no
# grammar at all (just plain shell), so it can't have that same syntax --
# but it can get the same EFFECT anyway. mpx always exports MP_PKG (the
# port's own pkg_name, e.g. "zstd" -- see mplib::hooks::port_env_args,
# shared by every phase of every port) into this script's own
# environment before it runs, so a same-named file under mpx.env.d/ can
# just be sourced conditionally, giving exactly mpx.conf's per-package
# section override semantics but for arbitrary shell/env content instead
# of a fixed key set. placed LAST (not first) so a per-package file's
# own exports win over anything set globally above -- same "more
# specific wins" precedence mpx.conf's own per-package sections already
# have. absent entirely (no mpx.env.d/ directory, or no file for this
# particular package) is a silent no-op, same as this whole file being
# absent.
#
# MUST be an "if", not a bare "A && B && C" statement: this whole file
# runs under "set -e" (see above), and busybox ash -- unlike the POSIX
# text some other shells go by -- aborts the ENTIRE script the moment
# ANY command in a bare "&&" list fails, not just the last one. written
# as a plain "[ -f ... ] && [ -f ... ] && . ..." line, this construct
# broke EVERY SINGLE BUILD ON THE SYSTEM the moment it was tried for
# real, the instant a package with no override file of its own (i.e.
# nearly every package) hit the middle "[ -f ... ]" test and failed it --
# caught only by actually running it, not by reasoning about the POSIX
# spec text. an "if" condition is unconditionally exempt from -e in
# every shell, which a bare AND-OR list statement is not guaranteed to
# be.
#
#if [ -n "${MP_PKG:-}" ] && [ -f "/etc/mpx.env.d/$MP_PKG.env" ]; then
#	. "/etc/mpx.env.d/$MP_PKG.env"
#fi