#!/bin/bash # Desc: Processes script arguments #==BEGIN Define script parameters== #===BEGIN Define variables=== : declare -ag arrayPosArgs #===END Define variables=== #===BEGIN Declare local script functions=== yell() { echo "$0: $*" >&2; } #o Yell, Die, Try Three-Fingered Claw technique die() { yell "$*"; exit 111; } #o Ref/Attrib: https://stackoverflow.com/a/25515370 try() { "$@" || die "cannot $*"; } #o vbm() { # Description: Prints verbose message ("vbm") to stderr if opVerbose is set to "true". # Usage: vbm "DEBUG :verbose message here" # Version 0.2.0 # Input: arg1: string # vars: opVerbose # Output: stderr # Depends: bash 5.1.16, GNU-coreutils 8.30 (echo, date) if [ "$opVerbose" = "true" ]; then functionTime="$(date --iso-8601=ns)"; # Save current time in nano seconds. echo "[$functionTime]:$0:""$*" 1>&2; # Display argument text. fi # End function return 0; # Function finished. } # Displays message if opVerbose true showUsage() { # Desc: Display script usage information # Usage: showUsage # Version 0.0.2 # Input: none # Output: stdout # Depends: GNU-coreutils 8.30 (cat) cat <<'EOF' USAGE: bktemp-processArgs [ options ] [FILE...] OPTIONS: -h, --help Display help information. --version Display script version. -v, --verbose Display debugging info. -i, --input-file Define input file path. -I, --input-dir Define input directory path. -o, --output-file Define output file path. -O, --output-dir Define output directory path. -- Indicate end of options. EXAMPLE: bktemp-processArgs -o foo.txt bktemp-processArgs -o foo.txt -- some_file.txt EOF } # Display information on how to use this script. showVersion() { # Desc: Displays script version and license information. # Usage: showVersion # Version: 0.0.2 # Input: scriptVersion var containing version string # Output: stdout # Depends: vbm(), yell, GNU-coreutils 8.30 # Initialize function vbm "DEBUG:showVersion function called." cat <<'EOF' bktemp-processArgs 1.0.0 Copyright (C) 2021 Steven Baltakatei Sandoval License GPLv3: GNU GPL version 3 This is free software; you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. GNU Coreutils 8.32 Copyright (C) 2020 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later . This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. EOF # End function vbm "DEBUG:showVersion function ended." return 0; # Function finished. } # Display script version. processArgs() { # Desc: Processes arguments provided to script. # Usage: processArgs "$@" # Version: 1.0.0 # Input: "$@" (list of arguments provided to the function) # Output: Sets following variables used by other functions: # opVerbose Indicates verbose mode enable status. (ex: "true", "false") # pathDirOut1 Path to output directory. # pathFileOut1 Path to output file. # pathDirIn1 Path to input directory. # pathFileIn1 Path to input file. # opFileOut1_overwrite Indicates whether file pathFileOut1 should be overwritten (ex: "true", "false"). # arrayPosArgs Array of remaining positional argments # Depends: # yell() Displays messages to stderr. # vbm() Displays messsages to stderr if opVerbose set to "true". # showUsage() Displays usage information about parent script. # showVersion() Displays version about parent script. # arrayPosArgs Global array for storing non-option positional arguments (i.e. arguments following the `--` option). # External dependencies: bash (5.1.16), echo # Ref./Attrib.: # [1]: Marco Aurelio (2014-05-08). "echo that outputs to stderr". https://stackoverflow.com/a/23550347 # [2]: "Handling positional parameters" (2018-05-12). https://wiki.bash-hackers.org/scripting/posparams # Initialize function vbm "DEBUG:processArgs function called." # Perform work while [ ! $# -eq 0 ]; do # While number of arguments ($#) is not (!) equal to (-eq) zero (0). #yell "DEBUG:Starting processArgs while loop." # Debug stderr message. See [1]. #yell "DEBUG:Provided arguments are:""$*" # Debug stderr message. See [1]. case "$1" in -h | --help) showUsage; exit 1;; # Display usage. --version) showVersion; exit 1;; # Show version -v | --verbose) opVerbose="true"; vbm "DEBUG:Verbose mode enabled.";; # Enable verbose mode. See [1]. -i | --input-file) # Define input file path if [ -f "$2" ]; then # If $2 is file that exists, set pathFileIn1 to $2, pop $2. pathFileIn1="$2"; shift; vbm "DEBUG:Input file pathFileIn1 set to:""$2"; else yell "ERROR: Specified input file does not exist:""$2"; yell "Exiting."; exit 1; fi ;; -I | --input-dir) # Define input directory path if [ -d "$2" ]; then # If $2 is dir that exists, set pathDirIn1 to $2, pop $2. pathDirIn1="$2"; shift; vbm "DEBUG:Input directory pathDirIn1 set to:""$2"; else # Display error if $2 is not a valid dir. yell "ERROR:Specified input directory does not exist:""$2"; yell "Exiting."; exit 1; fi ;; -o | --output-file) # Define output file path if [ -f "$2" ]; then # If $2 is file that exists, prompt user to continue to overwrite, set pathFileOut1 to $2, pop $2. yell "Specified output file $2 already exists. Overwrite? (y/n):" read -r m; case $m in y | Y | yes) opFileOut1_overwrite="true";; n | N | no) opFileOut1_overwrite="false";; *) yell "Invalid selection. Exiting."; exit 1;; esac if [ "$opFileOut1_overwrite" == "true" ]; then pathFileOut1="$2"; shift; vbm "DEBUG:Output file pathFileOut1 set to:""$2"; else yell "ERORR:Exiting in order to not overwrite output file:""$pathFileOut1"; exit 1; fi else pathFileOut1="$2"; shift; vbm "DEBUG:Output file pathFileOut1 set to:""$2"; fi ;; -O | --output-dir) # Define output directory path if [ -d "$2" ]; then # If $2 is dir that exists, set pathDirOut1 to $2, pop $2 pathDirOut1="$2"; shift; vbm "DEBUG:Output directory pathDirOut1 set to:""$2"; else yell "ERROR:Specified output directory is not valid:""$2"; yell "Exiting."; exit 1; fi ;; --) # End of all options. See [2]. shift; for arg in "$@"; do vbm "DEBUG:adding to arrayPosArgs:$arg"; arrayPosArgs+=("$arg"); done; break;; -*) showUsage; yell "ERROR: Unrecognized option."; exit 1;; # Display usage *) showUsage; yell "ERROR: Unrecognized argument."; exit 1;; # Handle unrecognized options. See [1]. esac shift done # End function vbm "DEBUG:processArgs function ended." return 0; # Function finished. } # Evaluate script options from positional arguments (ex: $1, $2, $3, etc.). #===END Declare local script functions=== #==END Define script parameters== #==BEGIN sample code== processArgs "$@"; yell "DEBUG:Provided arguments..:""$*" yell "DEBUG:opVerbose...........:${opVerbose:-}"; yell "DEBUG:pathDirOut1.........:${pathDirOut1:-}"; yell "DEBUG:pathFileOut1........:${pathFileOut1:-}"; yell "DEBUG:pathDirIn1..........:${pathDirIn1:-}"; yell "DEBUG:pathFileIn1.........:${pathFileIn1:-}"; yell "DEBUG:opFileOut1_overwrite:${opFileOut1_overwrite:-}"; yell "DEBUG:arrayPosArgs........:$(if [[ -v arrayPosArgs ]]; then declare -p arrayPosArgs; else printf ""; fi )"; #yell "DEBUG:arrayPosArgs........:${arrayPosArgs[*]}"; #==END sample code== # Author: Steven Baltaktei Sandoval # License: GPLv3+