#!/bin/sh

#
# This is a library of subroutines mostly intended for test scripts.
#

fail()
{
    printf "$@" 2>&1
    exit 99
}

skip()
{
    printf "$@" 2>&1
    exit 77
}

sleepf()
{
    (sleep .1 || sleep 1) > /dev/null 2>&1
}

seq_function()
{
    if [ $# -lt 1 ] || [ $# -gt 3 ]; then
	echo "bad args" >&2
    fi
    first=$1
    incr=1
    last=0
    case $# in
	3)
	    incr=$2
	    last=$3
	    ;;
	2)
	    last=$2
	    ;;
	1)
	    ;;
    esac
    while :; do
	printf '%d\n' "$first"
	first=$(( first + incr ))
	if [ "$first" -gt "$last" ]; then
	    break
	fi
    done
}

if ! seq 1 > /dev/null 2>&1; then
    seq()
    {
	seq_function "$@"
    }
fi

chr()
{
    printf '%b' "\\0$(printf %03o "$1")"
}

# If the locale is not set to a UTF-8 locale, set it to en_US.UTF-8
# or C.UTF-8.
set_locale()
{
    # Test for a usable locale.
    if ./is-utf8-locale 2> /dev/null; then
	return 0
    fi
    # Attempt to find/set a usable locale.
    unset LANG LC_CTYPE LC_COLLATE LC_MESSAGES LC_MONETARY LC_NUMERIC LC_TIME LC_ALL
    for i in en_US.UTF-8 en_US.utf8 C.UTF-8; do
	if env LC_ALL=$i ./is-utf8-locale 2> /dev/null; then
	    export LC_ALL=$i
	    return 0
	fi
    done
    # Fail.
    return 1
}

# Given two versions, return success if the first version is less than
# or equal to the second version.
versionlte()
{
    [  "$1" = "$(printf "$1\n$2\n" | sort -V | head -n1)" ]
}
versionlt() {
    if [ "$1" = "$2" ]; then
	return 1
    fi
    versionlte "$1" "$2"
}

# Tmux check.
tmux_check()
{
    need_major="$1"; shift
    need_minor="$1"; shift
    # OpenBSD tmux does not have '-V'.
    if [ "$(uname -s)" = "OpenBSD" ]; then
	openbsd_major="$(uname -r)"
	openbsd_major="${openbsd_major%%.*}"
	if [ "${openbsd_major}" -ge 6 ]; then
	    return 0
	fi
    fi
    version=$(tmux -V)
    if [ $? != 0 ]; then
	error "tmux unavailable\n"
	return 1
    fi
    if [ "$version" = "tmux master" ]; then
	return 0
    fi
    version=${version##tmux }

    if versionlt "$version" "$need_major.$need_minor"; then
	printf "tmux version %s too old\n" "$version" >&2
	return 1
    fi
    # Finally, check that tmux actually works to some degree.
    #
    # Use a different socket name.  On Cygwin, this tmux server is
    # slow to exit, and the actual test tmux can attach to it, causing
    # problems with missing environment variables.
    tmux_check_socket=$(mktemp -d /tmp/mosh-tmux-check.XXXXXXXX)
    tmux -f /dev/null -S "${tmux_check_socket}/s" -C new-session true
    rv=$?
    rm ${tmux_check_socket}/s
    rmdir ${tmux_check_socket}
    return $rv
}