split bash config and modify bash prompt

profiles/base/.bash/conf.d/02-gentoo-wintitle.bash

@@ -0,0 +1,78 @@
+#!/usr/bin/env bash
+# copied from https://gitweb.gentoo.org/repo/gentoo.git/tree/app-shells/bash
+
+# For information regarding the control sequences used, please refer to
+# https://invisible-island.net/xterm/ctlseqs/ctlseqs.html.
+
+genfun_set_win_title() {
+	# Advertise the fact that the presently running interactive shell will
+	# update the title. Doing so allows for its subprocesses to determine
+	# whether it is safe to set the title of their own accord. Note that 0
+	# refers to the value of Ps within the OSC Ps ; Pt BEL sequence.
+	export SHELL_SETS_TITLE=0
+
+	# Sets the window title with the Set Text Parameters control sequence.
+	# For screen, the sequence defines the hardstatus (%h) and for tmux, the
+	# pane_title (#T). For graphical terminal emulators, it is normal for
+	# the title bar to be affected.
+	genfun_set_win_title() {
+		local prompt
+
+		if [[ ${PROMPT_DIRTRIM} ]]; then
+			# Respect the value of PROMPT_DIRTRIM. If set as 0, the
+			# current working directory shall be shown in full.
+			prompt='\u@\h \w'
+		else
+			# Show the basename of the current working directory.
+			prompt='\u@\h \W'
+		fi
+		printf '\033]0;%s\007' "${prompt@P}"
+	}
+
+	genfun_set_win_title
+}
+
+unset -v SHELL_SETS_TITLE
+
+# Determine whether the terminal can handle the Set Text Parameters sequence.
+# The only terminals permitted here are those for which there is empirical
+# evidence that the sequence is supported and that the UTF-8 character encoding
+# is handled correctly. Quite rightly, this precludes many vintage terminals.
+case ${TERM} in
+	alacritty*|contour|foot*|tmux*|xterm-ghostty)
+		# The terminal emulator also supports XTWINOPS. If the PTY was
+		# created by sshd(8) then push the current window title to the
+		# stack and arrange for it to be popped upon exiting. Xterm also
+		# supports this but there are far too many terminal emulators
+		# that falsely identify as being xterm-compatible.
+		if [[ ${SSH_TTY} && ${SSH_TTY} == "$(tty)" ]]; then
+			trap 'printf "\033[23;0t"' EXIT
+			printf '\033[22;0t'
+		fi
+		;;
+	rxvt-unicode*|st-256color|xterm*)
+		# If the PTY was created by sshd(8) then proceed no further.
+		# Alas, there exist many operating environments in which the
+		# title would otherwise not be restored upon ssh(1) exiting.
+		# Those wanting for the title to be set regardless may adjust
+		# ~/.bashrc or create a bashrc.d drop-in to set PROMPT_COMMAND.
+		# For example, PROMPT_COMMAND=(genfun_set_win_title).
+		if [[ ${SSH_TTY} && ${SSH_TTY} == "$(tty)" ]]; then
+			return
+		fi
+		;;
+	screen*)
+		# If the PTY was created by sshd(8) and screen(1) was launched
+		# prior to the SSH session beginning, as opposed to afterwards,
+		# proceed no further. It is another case in which there would be
+		# no guarantee of the title being restored upon ssh(1) exiting.
+		if [[ ! ${WINDOW} && ${SSH_TTY} && ${SSH_TTY} == "$(tty)" ]]; then
+			return
+		fi
+		;;
+	*)
+		return
+esac
+
+# Arrange for the title to be updated each time the primary prompt is displayed.
+PROMPT_COMMAND+=('genfun_set_win_title')