#!/usr/bin/env bash

#

# resolve-prefix.sh — shared helper for check-soversion.sh and

# check-parallel-install.sh.

#

# Sourced (not executed) by both gate scripts to avoid copy-pasting the

# config.status prefix-resolution pipeline in two places.

#

# Inputs (must be set by the caller before sourcing):

# CONFIG_STATUS — absolute path to the config.status file in BUILD_DIR.

# fail — a shell function that prints a message and exits non-zero.

#

# Outputs (set in the caller's environment):

# RESOLVED_PREFIX — the configured installation prefix (e.g. /usr/local).

#

# After sourcing, callers typically derive:

# LIBDIR="$RESOLVED_PREFIX/lib"

# INCDIR="$RESOLVED_PREFIX/include"

#

# Design note: this helper is intentionally kept standalone (no sourcing of

# further helpers) so that each gate script remains easy to invoke in

# isolation without a complex dependency chain.

# Resolve prefix by asking config.status. The --config flag prints the

# original configure arguments, one per line after splitting on spaces. We

# grep for the --prefix= token, strip surrounding single-quotes (an autoconf

# quoting convention), and fall back to /usr/local when absent.

#

# POSIX-portable sed is used: avoid GNU \? (undefined in POSIX BRE/ERE).

# The trailing `|| true` matters when the caller runs under `set -e`: a default

# (unset) prefix makes the grep match nothing and exit 1, which pipefail would

# otherwise propagate and abort the script before the /usr/local fallback below.

RESOLVED_PREFIX="$("$CONFIG_STATUS" --config 2>/dev/null \

| tr ' ' '\n' \

| grep -E "^'?--prefix=" \

| head -1 \

| sed "s/^'*--prefix=//;s/'*$//" || true)"

[ -z "$RESOLVED_PREFIX" ] && RESOLVED_PREFIX="/usr/local"

# Guard: an absolute path is required for safe use in rm -rf / mkdir -p.

case "$RESOLVED_PREFIX" in

/*) ;;

*) fail "resolved prefix is not absolute: $RESOLVED_PREFIX" ;;

esac