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Diffstat (limited to 'scripts/lib/lib_common.sh')
| -rw-r--r-- | scripts/lib/lib_common.sh | 134 |
1 files changed, 134 insertions, 0 deletions
diff --git a/scripts/lib/lib_common.sh b/scripts/lib/lib_common.sh new file mode 100644 index 0000000..58ee5ba --- /dev/null +++ b/scripts/lib/lib_common.sh @@ -0,0 +1,134 @@ +#!/bin/sh + +progname=$(basename "${0}") + +# @FUNCTION: err +# @USAGE: [-x] <message> ... +# @DESCRIPTION: +# Print given messages to stderr line by line and exit with status 1. +# +# If "-x" is specified, suppress the program prefix (`program: `) +# from the output. Otherwise, the first line is prefixed with "program: ". +# +# This function is intended for fatal errors; it always exits the script. +# @EXAMPLE: +# err "Invalid usage" "Try '${progname} -h' for help." +err() { + if [ "${1}" != "-x" ]; then + printf "%s: " "${progname}" + else + shift + fi + + for line in "${@}"; do + echo "${line}" >&2 + done + exit 1 +} + +# @FUNCTION: invalid_use +# USAGE: [-h] +# @DESCRIPTION: +# Output a usage error message. If `-h` is not specified output: +# "<program>: Invalid usage " +# "Try 'program -h' for help." +# else output only: +# "Try 'program -h' for help." + +invalid_use() { + [ "${1}" = "-h" ] && err -x "Try '${progname} -h' for help." + err "Invalid usage" "Try '${progname} -h' for help." +} + +# @FUNCTION: check_program +# USAGE: <command> [error-msg] +# @DESCRIPTION: +# Check if command exists on the system. +# If not, print an error message to stderr and exit with status 1. +# The default error message is "`command` must be installed" +# but can optionally be overwritten. +# +# @EXAMPLE: +# Check if pulseaudio is installed. +# +# check_program "pactl" "pulseaudio must be installed" + +check_program() { + command -v "${1}" > /dev/null 2>&1 && return 0 + [ -n "${2}" ] && err "${2}" + err "${1} must be installed" +} + +# @FUNCTION: get_random_filename +# @USAGE: get_random_filename [parentdir] <extension> +# @DESCRIPTION: +# Write a random file path to stdout, under parentdir, (if provided else under /tmp) with the extension. +# +# @EXAMPLE: +# Get a filepath in the `/var` directory with the extension `.png` +# +# get_random_filename .png /var + +get_random_filename() { + [ "${#}" -eq 2 ] && parentdir="${2}" || parentdir="/tmp" + + extension="${1}" + + echo "${parentdir}/$(date '+%b%d::%H%M%S')${extension}" +} + +# @FUNCTION: run +# @USAGE: [--reload-status] [--reload-compositor] [--success-notify <msg>] [--failure-notify <msg>] <command> [success-msg] [failure-msg] +# @DESCRIPTION: +# Safely execute a simple shell command, print optional success/failure messages, +# and optionally reload the status bar or restart the compositor. +# +# Success messages are printed to stdout; failure messages are printed to stderr. +# Optional desktop notifications can be sent using --success-notify and --failure-notify. +# Command output is not suppressed. +# +# Options: +# --reload-status Reload the status bar (via `slreload`). +# --reload-compositor Restart the compositor (kills and restarts `picom`). +# --success-notify <msg> Send a desktop notification on success. +# --failure-notify <msg> Send a desktop notification on failure. +# +# Restrictions: +# - Does NOT use `eval`; only simple commands and arguments are supported. +# - Shell operators like `&&`, `||`, `|`, `>`, `>>`, etc. will NOT work. +# - This design prevents unintended execution and makes the function safe in scripts. +# +# Return value: +# Exits with 0 if the command succeeds, 1 otherwise. +# +# @EXAMPLES: +# # Run xwallpaper and print the image path on success +# run "xwallpaper --zoom ${image}" "${image}" +# +# # Restart compositor and show a success message +# run --reload-compositor "xwallpaper --zoom ${image}" "Wallpaper updated" "Wallpaper failed" +# +# # With notification hooks +# run --success-notify "Wallpaper set" \ +# --failure-notify "Wallpaper failed" \ +# "xwallpaper --zoom ${image}" "Wallpaper updated" "Wallpaper failed" + +run() { + no_exit=0 + reload_status=0 + reload_compositor=0 + + [ "${1}" = "--no-exit" ] && no_exit=1 && shift + [ "${1}" = "--reload-status" ] && reload_status=1 && shift + [ "${1}" = "--reload-compositor" ] && reload_compositor=1 && shift + + trap ' + [ "${reload_status}" -eq 1 ] && status_handle reload + [ "${reload_compositor}" -eq 1 ] && compositor_handle start + ' EXIT + + [ "${reload_compositor}" -eq 1 ] && compositor_handle stop + + eval "${@}" + [ "${no_exit}" -eq 1 ] || exit "${?}" +} |