1 files changed, 198 insertions, 0 deletions
diff --git a/configure b/configure
new file mode 100755
index 0000000..60d7a92
--- /dev/null
+++ b/configure
@@ -0,0 +1,198 @@
+#!/bin/sh
+
+# Copyright © Tavian Barnes <tavianator@tavianator.com>
+# SPDX-License-Identifier: 0BSD
+
+# bfs build configuration script
+
+set -eu
+
+# Default to `make`
+MAKE="${MAKE:-make}"
+
+# Pass -j$(nproc) unless MAKEFLAGS is set
+if [ "${MAKEFLAGS+y}" ]; then
+    j=""
+else
+    j="-j$({ nproc || sysctl -n hw.ncpu || getconf _NPROCESSORS_ONLN || echo 1; } 2>/dev/null)"
+fi
+
+# Convert kebab-case to UPPER_CASE
+toupper() {
+    printf '%s' "$1" | tr 'a-z-' 'A-Z_'
+}
+
+# Report an argument parsing error
+invalid() {
+    printf 'error: Unrecognized option "%s"\n\n' "$1" >&2
+    printf 'Run %s --help for more information.\n' "$0" >&2
+    exit 1
+}
+
+for arg; do
+    # --[(enable|disable|with|without)-]$name[=$value]
+    value="${arg#*=}"
+    name="${arg%%=*}"
+    name="${name#--}"
+    case "$arg" in
+        --enable-*|--disable-*|--with-*|--without-*)
+            name="${name#*-}"
+            ;;
+    esac
+    NAME=$(printf '%s' "$name" | tr 'a-z-' 'A-Z_')
+
+    # y/n modality
+    case "$arg" in
+        --enable-*|--with-*)
+            case "$arg" in
+                *=y|*=yes) yn=y ;;
+                *=n|*=no) yn=n ;;
+                *=*) invalid "$arg" ;;
+                *) yn=y ;;
+            esac
+            ;;
+        --disable-*|--without-*)
+            case "$arg" in
+                *=*) invalid "arg" ;;
+                *) yn=n ;;
+            esac
+            ;;
+    esac
+
+    # Fix up --enable-lib* to --with-lib*
+    case "$arg" in
+        --enable-*|--disable-*)
+            case "$name" in
+                libacl|libcap|libselinux|liburing|oniguruma)
+                    old="$arg"
+                    case "$arg" in
+                        --enable-*) arg="--with-${arg#--*-}" ;;
+                        --disable-*) arg="--without-${arg#--*-}" ;;
+                    esac
+                    printf 'warning: Treating "%s" like "%s"\n' "$old" "$arg" >&2
+                    ;;
+            esac
+        ;;
+    esac
+
+    case "$arg" in
+        -h|--help)
+            cat <<EOF
+Usage:
+
+  \$ $0 [--enable-*|--disable-*] [--with-*|--without-*] [CC=...] [...]
+  \$ $MAKE $j
+
+Variables set in the environment or on the command line will be picked up:
+
+  MAKE
+      The make implementation to use
+  CC
+      The C compiler to use
+
+  CPPFLAGS="-I... -D..."
+  CFLAGS="-W... -f..."
+  LDFLAGS="-L... -Wl,..."
+      Preprocessor/compiler/linker flags
+
+  LDLIBS="-l... -l..."
+      Dynamic libraries to link
+
+  EXTRA_{CPPFLAGS,CFLAGS,LDFLAGS,LDLIBS}
+      Adds to the default flags, instead of replacing them
+
+The default flags result in a plain debug build.  Other build profiles include:
+
+  --enable-release
+      Enable optimizations, disable assertions
+  --enable-{asan,lsan,msan,tsan,ubsan}
+      Enable sanitizers
+  --enable-gcov
+      Enable code coverage instrumentation
+
+External dependencies are auto-detected by default, but you can build --with or
+--without them explicitly:
+
+  --with-libacl      --without-libacl
+  --with-libcap      --without-libcap
+  --with-libselinux  --without-libselinux
+  --with-liburing    --without-liburing
+  --with-oniguruma   --without-oniguruma
+
+Packaging:
+
+  --prefix=/path
+      Set the installation prefix (default: /usr)
+  --mandir=/path
+      Set the man page directory (default: \$PREFIX/share/man)
+
+This script is a thin wrapper around a makefile-based configuration system.
+Any other arguments will be passed directly to the $MAKE invocation, e.g.
+
+  \$ $0 $j V=1
+EOF
+            exit 0
+            ;;
+
+        --enable-*|--disable-*)
+            case "$name" in
+                release|asan|lsan|msan|tsan|ubsan|lint|gcov)
+                    shift
+                    set -- "$@" "$NAME=$yn"
+                    ;;
+                *)
+                    invalid "$arg"
+                    ;;
+            esac
+            ;;
+
+        --with-*|--without-*)
+            case "$name" in
+                libacl|libcap|libselinux|liburing|oniguruma)
+                    shift
+                    set -- "$@" "WITH_$NAME=$yn"
+                    ;;
+                *)
+                    invalid "$arg"
+                    ;;
+            esac
+            ;;
+
+        --prefix=*|--mandir=*)
+            shift
+            set -- "$@" "$NAME=$value"
+            ;;
+
+        --infodir=*|--build=*|--host=*|--target=*)
+            shift
+            printf 'warning: Ignoring option "%s"\n' "$arg" >&2
+            ;;
+
+        MAKE=*)
+            shift
+            MAKE="$value"
+            ;;
+
+        # make flag (-j2) or variable (CC=clang)
+        -*|*=*)
+            continue
+            ;;
+
+        *)
+            invalid "$arg"
+            ;;
+    esac
+done
+
+# Get the relative path to the source tree based on how the script was run
+DIR=$(dirname -- "$0")
+
+# Set up symbolic links for out-of-tree builds
+for f in Makefile build completions docs src tests; do
+    test -e "$f" || ln -s "$DIR/$f" "$f"
+done
+
+# Set MAKEFLAGS to -j$(nproc) if it's unset
+export MAKEFLAGS="${MAKEFLAGS-$j}"
+
+$MAKE -rf build/config.mk "$@"