moved helpers separately

helpers/fun.sh

@@ -0,0 +1,89 @@
+#!/usr/bin/env bash
+# ------------------------------------------------------------------------------
+# Copyright (c) 2013-2026 Geoffray Levasseur <fatalerrors@geoffray-levasseur.org>
+# Protected by the BSD3 license. Please read bellow for details.
+#
+# * Redistribution and use in source and binary forms,
+# * with or without modification, are permitted provided
+# * that the following conditions are met:
+# *
+# *   Redistributions of source code must retain the above
+# *   copyright notice, this list of conditions and the
+# *   following disclaimer.
+# *
+# *   Redistributions in binary form must reproduce the above
+# *   copyright notice, this list of conditions and the following
+# *   disclaimer in the documentation and/or other materials
+# *   provided with the distribution.
+# *
+# *   Neither the name of the copyright holder nor the names
+# *   of any other contributors may be used to endorse or
+# *   promote products derived from this software without
+# *   specific prior written permission.
+# *
+# * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
+# * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
+# * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+# * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+# * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
+# * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+# * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+# * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+# * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+# * OF SUCH DAMAGE.
+# ------------------------------------------------------------------------------
+
+# Private helpers of profile.d/fun.sh, loaded by the module itself.
+
+# Convert a number of milliseconds into a seconds string usable by sleep
+# (1500 -> 1.500), in pure bash (no awk fork per call).
+# Usage: _fun_ms_to_s <ms>
+_fun_ms_to_s()
+{
+    printf '%d.%03d' $(( $1 / 1000 )) $(( $1 % 1000 ))
+}
+export -f _fun_ms_to_s
+
+# Fail with a message unless a terminal is available: the demos wait for a key
+# read from /dev/tty to stop.
+# Usage: _fun_need_tty <command-name>
+_fun_need_tty()
+{
+    if ! { : </dev/tty; } 2>/dev/null; then
+        disp E "$1: a terminal is required (it runs until a key is pressed)."
+        return 1
+    fi
+}
+export -f _fun_need_tty
+
+# Wait for a key press, then stop the background job $1 and its children.
+# The job runs as "( ... ) &"; with job control (interactive shell) it is the
+# leader of its own process group, which is signalled as a whole. Without job
+# control that group does not exist, so its direct children (the pipeline) are
+# killed first, then the subshell. SIGINT is trapped meanwhile so that Ctrl-C
+# stops the job like a key press instead of aborting the caller and leaving it
+# running. The wait is a polling loop of short timed reads: a blocking read is
+# restarted by bash after a trapped signal and would never notice the Ctrl-C.
+# Usage: _fun_stop_on_key <pid>
+_fun_stop_on_key()
+{
+    local pid=$1 old_int interrupted=0
+    old_int=$(trap -p INT)
+    trap 'interrupted=1' INT
+    while (( ! interrupted )); do
+        IFS= read -r -n 1 -s -t 0.3 _ </dev/tty && break
+        # Status above 128 is just the timeout; anything else (such as end of
+        # input on the terminal) ends the wait.
+        (( $? > 128 )) || break
+    done
+    kill -- -"$pid" 2>/dev/null || {
+        pkill -P "$pid" 2>/dev/null
+        kill "$pid" 2>/dev/null
+    }
+    wait "$pid" 2>/dev/null
+    trap - INT
+    _trap_restore "$old_int"
+    return 0
+}
+export -f _fun_stop_on_key