krino: release 0.0.1 — man pages, install, examples, cross and release, README, changelogv0.0.1

Also: undo removes the directories its run created; a hardlink is never a
duplicate of its own other name; a flag written before "undo" is honoured;
--version prints no leading v. Duplicate conditions with different scopes
not sharing an original is documented as a known limitation.

1 files changed, 99 insertions, 0 deletions

diff --git a/scripts/deps b/scripts/deps
new file mode 100755
index 0000000..06faaa2
--- /dev/null
+++ b/scripts/deps
@@ -0,0 +1,99 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-3.0-or-later
+#
+# scripts/deps: install krino's optional content extractors with the host's
+# system package manager, per docs/design.md §14.
+#
+# --print prints the exact command this script would run (and the reason,
+# when one platform's package list differs from the others), then exits
+# without running anything and without asking for privileges. `make deps`
+# calls this script with no flag; plain `make`/`make build` never calls it
+# at all, so plain `make` never asks for privileges (§14).
+#
+# Detection:
+#   - Debian family - /etc/os-release's ID *or* ID_LIKE names "debian" as
+#     one of its (possibly multi-word) values. Devuan is ID=devuan,
+#     ID_LIKE=debian: keying on ID=debian alone would leave it unrecognised.
+#     -> apt-get install poppler-utils catdoc antiword
+#   - FreeBSD (uname -s) -> pkg install poppler-utils antiword. catdoc is
+#     left out on purpose: it pulls in tcl/tk.
+#   - OpenBSD (uname -s) -> pkg_add poppler-utils catdoc antiword
+#   - anything else: print what is needed and exit non-zero. This script
+#     never guesses a package manager.
+#
+# Privileges: doas if present, else sudo; if neither exists (and we are not
+# already root), the command is printed for the user to run as root
+# themselves, rather than attempting it unprivileged and failing silently.
+
+set -eu
+
+print_only=0
+case "${1:-}" in
+	--print) print_only=1 ;;
+	"") ;;
+	*)
+		echo "usage: $0 [--print]" >&2
+		exit 2
+		;;
+esac
+
+# is_debian_family: true if /etc/os-release's ID or ID_LIKE contains
+# "debian" as one of its space-separated words.
+is_debian_family() {
+	[ -r /etc/os-release ] || return 1
+	(
+		. /etc/os-release
+		for word in ${ID:-} ${ID_LIKE:-}; do
+			[ "$word" = "debian" ] && exit 0
+		done
+		exit 1
+	)
+}
+
+# privileged CMD...: CMD prefixed with doas or sudo, whichever is found
+# first; unprefixed if we are already root or if neither exists (the
+# caller decides what to do in that last case).
+privileged() {
+	if [ "$(id -u)" = 0 ]; then
+		printf '%s\n' "$*"
+	elif command -v doas >/dev/null 2>&1; then
+		printf 'doas %s\n' "$*"
+	elif command -v sudo >/dev/null 2>&1; then
+		printf 'sudo %s\n' "$*"
+	else
+		printf '%s\n' "$*"
+	fi
+}
+
+note=""
+if is_debian_family; then
+	pkgcmd="apt-get install poppler-utils catdoc antiword"
+elif [ "$(uname -s)" = "FreeBSD" ]; then
+	pkgcmd="pkg install poppler-utils antiword"
+	note="catdoc left out on FreeBSD: it pulls in tcl/tk."
+elif [ "$(uname -s)" = "OpenBSD" ]; then
+	pkgcmd="pkg_add poppler-utils catdoc antiword"
+else
+	echo "krino's optional extractors: poppler-utils (pdftotext), catdoc, antiword" >&2
+	echo "no supported package manager detected (uname -s: $(uname -s), no debian-family /etc/os-release)" >&2
+	echo "install them yourself with whatever this system uses" >&2
+	exit 1
+fi
+
+cmd=$(privileged $pkgcmd)
+
+[ -n "$note" ] && echo "$note"
+
+if [ "$print_only" = 1 ]; then
+	echo "$cmd"
+	exit 0
+fi
+
+if [ "$(id -u)" != 0 ] && ! command -v doas >/dev/null 2>&1 && ! command -v sudo >/dev/null 2>&1; then
+	echo "neither doas nor sudo found; run this yourself as root:" >&2
+	echo "$cmd" >&2
+	exit 1
+fi
+
+echo "$cmd"
+exec $cmd