tools: Add Arch Linux setup script to install dependencies

This was intentionally kept simple (matches the philosophy of Arch).

In particular I wasn't so concerned about what is a required build
dependency and what is an optional build dependency to compile the
programs. I don't know why one would ever wish to skip installation
of non-essential library dependencies. But others are very welcome
to extend this intentionally barebones effort.

The script also adds an "--install-all" flag to install everything
at once. I keep forgetting the name of the other options.

I used the build optional flag to install packages required to build
documentation and so on. Ancillary stuff.

tools/arch-setup.sh

@@ -0,0 +1,127 @@
+#!/bin/bash
+# Setup development environment on Arch Linux
+#
+# Wireshark - Network traffic analyzer
+# By Gerald Combs <gerald@wireshark.org>
+# Copyright 1998 Gerald Combs
+#
+# SPDX-License-Identifier: GPL-2.0-or-later
+#
+# We drag in tools that might not be needed by all users; it's easier
+# that way.
+#
+
+if [ "$1" = "--help" ]
+then
+	printf "\\nUtility to setup a pacman-based system for Wireshark development.\\n"
+	printf "The basic usage installs the needed software\\n\\n"
+	printf "Usage: %s [--install-optional] [...other options...]\\n" "$0"
+	printf "\\t--install-optional: install optional software as well\\n"
+	printf "\\t--install-test-deps: install packages required to run all tests\\n"
+	printf "\\t--install-all: install everything\\n"
+	printf "\\t[other]: other options are passed as-is to pacman\\n"
+	printf "\\tPass --noconfirm to bypass any \"are you sure?\" messages.\\n"
+	exit 1
+fi
+
+# Check if the user is root
+if [ "$(id -u)" -ne 0 ]
+then
+	echo "You must be root."
+	exit 1
+fi
+
+ADDITIONAL=0
+TESTDEPS=0
+AUR=0
+for arg; do
+	case $arg in
+		--install-optional)
+			ADDITIONAL=1
+			;;
+		--install-test-deps)
+			TESTDEPS=1
+			;;
+		--install-all)
+			ADDITIONAL=1
+			TESTDEPS=1
+			AUR=1
+			;;
+		*)
+			OPTIONS="$OPTIONS $arg"
+			;;
+	esac
+done
+
+BASIC_LIST="base-devel \
+	bcg729 \
+	brotli \
+	c-ares \
+	cmake \
+	git \
+	glib2 \
+	gnutls \
+	krb5 \
+	libcap \
+	libgcrypt \
+	libilbc \
+	libmaxminddb \
+	libnghttp2 \
+	libnl \
+	libpcap \
+	libssh \
+	libxml2 \
+	lua52 \
+	lz4 \
+	minizip \
+	ninja \
+	pcre2 \
+	perl \
+	python \
+	qt5-base \
+	qt5-multimedia \
+	qt5-tools \
+	sbc \
+	snappy \
+	spandsp \
+	speexdsp \
+	zlib \
+	zstd"
+
+ADDITIONAL_LIST="asciidoctor \
+	ccache \
+	doxygen \
+	libxslt"
+
+TESTDEPS_LIST="python-pytest \
+	python-pytest-xdist"
+
+ACTUAL_LIST=$BASIC_LIST
+
+if [ $ADDITIONAL -ne 0 ]
+then
+	ACTUAL_LIST="$ACTUAL_LIST $ADDITIONAL_LIST"
+fi
+
+if [ $TESTDEPS -ne 0 ]
+then
+	ACTUAL_LIST="$ACTUAL_LIST $TESTDEPS_LIST"
+fi
+
+# Partial upgrades are unsupported.
+pacman -Syu --needed $ACTUAL_LIST $OPTIONS || exit 2
+
+if [ $ADDITIONAL -eq 0 ]
+then
+	printf "\n*** Optional packages not installed. Rerun with --install-optional to have them.\n"
+fi
+
+if [ $TESTDEPS -eq 0 ]
+then
+	printf "\n*** Test deps not installed. Rerun with --install-test-deps to have them.\n"
+fi
+
+if [ $AUR -ne 0 ]
+then
+	printf "\n*** These and other packages may also be found in the AUR: libsmi.\n"
+fi