478 lines
		
	
	
		
			14 KiB
		
	
	
	
		
			Bash
		
	
	
	
	
	
		
		
			
		
	
	
			478 lines
		
	
	
		
			14 KiB
		
	
	
	
		
			Bash
		
	
	
	
	
	
|   | # | ||
|  | # Bash Functions for sourcing in scripts. | ||
|  | # | ||
|  | # This is a copy of some of the functions for HPR project use. | ||
|  | # | ||
|  | #       ${HOME}/HPR/InternetArchive/function_lib.sh | ||
|  | # | ||
|  | # Revised: 2024-06-15 18:13:28 | ||
|  | # | ||
|  | 
 | ||
|  | 
 | ||
|  | #===  FUNCTION  ================================================================ | ||
|  | #        NAME:  abs_diff | ||
|  | # DESCRIPTION:  Compute the difference between two numbers, returning an | ||
|  | #               absolute value | ||
|  | #  PARAMETERS:  $1      first number | ||
|  | #               $2      second number | ||
|  | #     RETURNS:  The absolute value as a string | ||
|  | #=============================================================================== | ||
|  | function abs_diff { | ||
|  |     local p1="${1:?Usage: abs_diff n1 n2}" | ||
|  |     local p2="${2:?Usage: abs_diff n1 n2}" | ||
|  | 
 | ||
|  |     echo $((p1 >= p2 ? p1 - p2 : p2 - p1)) | ||
|  | } | ||
|  | 
 | ||
|  | #===  FUNCTION  ================================================================ | ||
|  | #          NAME:  cleanup_temp | ||
|  | #   DESCRIPTION:  Cleanup temporary files in case of a keyboard interrupt | ||
|  | #                 (SIGINT) or a termination signal (SIGTERM) and at script | ||
|  | #                 exit | ||
|  | #    PARAMETERS:  * - names of temporary files to delete | ||
|  | #       RETURNS:  Nothing | ||
|  | #=============================================================================== | ||
|  | function cleanup_temp { | ||
|  |     for tmp in "$@"; do | ||
|  |         [ -e "$tmp" ] && rm --force "$tmp" | ||
|  |     done | ||
|  |     exit 0 | ||
|  | } | ||
|  | 
 | ||
|  | #===  FUNCTION  ================================================================ | ||
|  | #         NAME: _DEBUG | ||
|  | #  DESCRIPTION: Writes one or more messages if in DEBUG mode. Each argument is | ||
|  | #               seen as a message and is written on a separate line. | ||
|  | #               References the global variable 'DEBUG' which is expected to be | ||
|  | #               True if debug output is wanted. | ||
|  | #   PARAMETERS: List of messages | ||
|  | #      RETURNS: Nothing | ||
|  | #=============================================================================== | ||
|  | _DEBUG () { | ||
|  |     [ "$DEBUG" == 0 ] && return | ||
|  |     for msg in "$@"; do | ||
|  |         printf 'D> %s\n' "$msg" | ||
|  |     done | ||
|  | } | ||
|  | 
 | ||
|  | #===  FUNCTION  ================================================================ | ||
|  | #         NAME: yes_no | ||
|  | #  DESCRIPTION: Read a Yes or No response from STDIN (only these values are | ||
|  | #               accepted) and return a suitable numeric value. | ||
|  | #   PARAMETERS: 1 - Prompt string for the read | ||
|  | #               2 - Default value (optional) | ||
|  | #      RETURNS: 0 for a response of Y or YES, 1 otherwise | ||
|  | #=============================================================================== | ||
|  | yes_no () { | ||
|  |     local prompt="${1:?Usage: yes_no prompt [default]}" | ||
|  |     local default="${2^^}" | ||
|  |     local ans res | ||
|  | 
 | ||
|  |     if [[ $prompt =~ %s ]]; then | ||
|  |         if [[ -n $default ]]; then | ||
|  |             default=${default:0:1} | ||
|  |             # shellcheck disable=SC2059 | ||
|  |             # { | ||
|  |             case "$default" in | ||
|  |                 Y) printf -v prompt "$prompt" "[Y/n]" ;; | ||
|  |                 N) printf -v prompt "$prompt" "[y/N]" ;; | ||
|  |                 *) echo "Error: ${FUNCNAME[0]} @ line ${BASH_LINENO[0]}: Default must be 'Y' or 'N'" | ||
|  |                    exit 1 | ||
|  |                    ;; | ||
|  |             esac | ||
|  |             # } | ||
|  |         else | ||
|  |             echo "Error: ${FUNCNAME[0]} @ line ${BASH_LINENO[0]}: Default required" | ||
|  |             exit 1 | ||
|  |         fi | ||
|  |     fi | ||
|  | 
 | ||
|  |     # | ||
|  |     # Loop until a valid input is received | ||
|  |     # | ||
|  |     while true; do | ||
|  |         # | ||
|  |         # Read and handle CTRL-D (EOF) | ||
|  |         # | ||
|  |         read -r -e -p "$prompt" ans | ||
|  |         res="$?" | ||
|  |         if [[ $res -ne 0 ]]; then | ||
|  |             echo "Read aborted" | ||
|  |             return 1 | ||
|  |         fi | ||
|  | 
 | ||
|  |         [ -z "$ans" ] && ans="$default" | ||
|  | 
 | ||
|  |         # | ||
|  |         # Look for valid replies and return appropriate values. Print an error | ||
|  |         # message otherwise and loop around for another go | ||
|  |         # | ||
|  |         if [[ ${ans^^} =~ ^Y(E|ES)?$ ]]; then | ||
|  |             return 0 | ||
|  |         elif [[ ${ans^^} =~ ^NO?$ ]]; then | ||
|  |             return 1 | ||
|  |         else | ||
|  |             echo "Invalid reply; please use 'Y' or 'N'" | ||
|  |         fi | ||
|  |     done | ||
|  | } | ||
|  | 
 | ||
|  | #===  FUNCTION  ================================================================ | ||
|  | #         NAME: make_file_list | ||
|  | #  DESCRIPTION: Given an array of filenames select from them and make | ||
|  | #               an array of choices in a different order if required | ||
|  | #   PARAMETERS: 1 - input array name | ||
|  | #               2 - output array name | ||
|  | #      RETURNS: True (0) if a new list was generated, false (1) otherwise | ||
|  | #=============================================================================== | ||
|  | make_file_list () { | ||
|  |     local -n inarr=${1:?Usage make_file_list input_array out_array} | ||
|  |     local -n outarr=${2:?Usage make_file_list input_array out_array} | ||
|  |     local i msg prompt range lines choices | ||
|  | 
 | ||
|  |     # | ||
|  |     # Print the array contents | ||
|  |     # | ||
|  |     lines="${#inarr[@]}" | ||
|  |     for ((i = 0; i < lines; i++)); do | ||
|  |         printf '%-2d %s\n' "$((i+1))" "${inarr[$i]}" | ||
|  |     done | ||
|  | 
 | ||
|  |     msg="Enter a range like '1,2' or '4-7'" | ||
|  |     if [[ $lines -eq 1 ]]; then | ||
|  |         prompt="1" | ||
|  |     else | ||
|  |         prompt="1-$lines" | ||
|  |         msg+=" (between 1 and $lines)" | ||
|  |     fi | ||
|  | 
 | ||
|  |     # | ||
|  |     # Choose array elements by number where order is significant | ||
|  |     # | ||
|  |     echo "$msg" | ||
|  |     if read_value "Files to add to list: " range "$prompt"; then | ||
|  |         # | ||
|  |         # If there's a range then parse it and write the relevant elements to the | ||
|  |         # target array, otherwise exit with an error | ||
|  |         # | ||
|  |         if [[ -n "$range" ]]; then | ||
|  |             range_parse "$lines" "$range" choices 0 | ||
|  |             for i in $choices; do | ||
|  |                 outarr+=("${inarr[$((i-1))]}") | ||
|  |             done | ||
|  |         else | ||
|  |             echo "No files chosen; no list created" | ||
|  |             return 1 | ||
|  |         fi | ||
|  | 
 | ||
|  |         return 0 | ||
|  |     else | ||
|  |         return 1 | ||
|  |     fi | ||
|  | 
 | ||
|  | } | ||
|  | 
 | ||
|  | #===  FUNCTION  ================================================================ | ||
|  | #          NAME:  range_parse | ||
|  | #   DESCRIPTION:  Parse a collection of ranges | ||
|  | #    PARAMETERS:  - maximum limit of the range | ||
|  | #                 - entered range expression (e.g. 1-3,7,14) | ||
|  | #                 - name of variable to receive the result | ||
|  | #       RETURNS:  Writes a list of values to the nominated variable | ||
|  | #=============================================================================== | ||
|  | function range_parse { | ||
|  |     local max=${1?range_parse: arg 1 missing} | ||
|  |     local range=${2?range:parse: arg2 missing} | ||
|  |     local result=${3?range:parse: arg3 missing} | ||
|  |     local tosort=${4:-1} | ||
|  | 
 | ||
|  |     local selection= | ||
|  | 
 | ||
|  |     # | ||
|  |     # Turn this off. It affects how some code below behaves | ||
|  |     # | ||
|  |     set +o nounset | ||
|  | 
 | ||
|  |     # | ||
|  |     # Remove spaces from the range | ||
|  |     # | ||
|  |     range=${range// /} | ||
|  | 
 | ||
|  |     # | ||
|  |     # Check for invalid characters | ||
|  |     # | ||
|  |     if [[ $range =~ [^0-9,-] ]]; then | ||
|  |         echo "Invalid range: $range" | ||
|  |         exit | ||
|  |     fi | ||
|  | 
 | ||
|  |     # | ||
|  |     # Slice up the sub-ranges separated by commas and turn all n-m expressions | ||
|  |     # into the intermediate values. Trim the trailing space from the | ||
|  |     # concatenation. | ||
|  |     # | ||
|  |     until [[ -z $range ]]; do | ||
|  |         if [[ $range =~ [,] ]]; then | ||
|  |             item=${range%%,*} | ||
|  |             range=${range#*,} | ||
|  |         else | ||
|  |             item=$range | ||
|  |             range= | ||
|  |         fi | ||
|  |         if [[ $item =~ [-] ]]; then | ||
|  |             item=${item//-/ } | ||
|  |             if [[ $item =~ ^([0-9]{1,}).([0-9]{1,})$ ]]; then | ||
|  |                 # shellcheck disable=SC2086 | ||
|  |                 item=$(seq -s' ' $item) | ||
|  |             else | ||
|  |                 echo "Invalid sequence: ${item/ /-}" | ||
|  |                 item= | ||
|  |             fi | ||
|  |         fi | ||
|  |         selection+="$item " | ||
|  |     done | ||
|  |     selection=${selection%% } | ||
|  | 
 | ||
|  |     # | ||
|  |     # Check for out of bounds problems, sort values and and make unique | ||
|  |     # | ||
|  |     if [[ ${#selection} -gt 0 ]]; then | ||
|  |         # | ||
|  |         # Validate the resulting range | ||
|  |         # | ||
|  |         declare -a sel err msg | ||
|  |         for i in $selection; do | ||
|  |             if [[ $i -lt 1 || $i -gt $max ]]; then | ||
|  |                 err+=( $i ) | ||
|  |             else | ||
|  |                 sel+=( $i ) | ||
|  |             fi | ||
|  |         done | ||
|  | 
 | ||
|  |         # | ||
|  |         # Report any errors | ||
|  |         # | ||
|  |         if [[ ${#err[*]} -gt 0 ]]; then | ||
|  |             msg=( $(for i in ${err[*]}; do echo $i; done | sort -un) ) | ||
|  |             if [[ ${#msg[*]} -gt 1 ]]; then | ||
|  |                 printf "Values out of range: %s .. %s\n" ${msg[0]} ${msg[${#msg[*]}-1]} | ||
|  |             else | ||
|  |                 printf "Value out of range: %s\n" ${msg[0]} | ||
|  |             fi | ||
|  |         fi | ||
|  | 
 | ||
|  |         # | ||
|  |         # Rebuild the selection | ||
|  |         # | ||
|  |         selection= | ||
|  |         if [[ ${#sel[*]} -gt 0 ]]; then | ||
|  |             if [[ $tosort -eq 1 ]]; then | ||
|  |                 selection="$(for i in ${sel[*]}; do echo $i; done | sort -un)" | ||
|  |             else | ||
|  |                 selection="$(for i in ${sel[*]}; do echo $i; done)" | ||
|  |             fi | ||
|  |         fi | ||
|  |     fi | ||
|  | 
 | ||
|  |     # | ||
|  |     # Return the result | ||
|  |     # | ||
|  |     eval $result=\"$selection\" | ||
|  | 
 | ||
|  |     return | ||
|  | } | ||
|  | 
 | ||
|  | #===  FUNCTION  ================================================================ | ||
|  | #         NAME: pad | ||
|  | #  DESCRIPTION: Pad $text to the left with $char characters to length $length | ||
|  | #   PARAMETERS: 1 - the text string to pad (no default) | ||
|  | #               2 - how long the padded string is to be (default 80) | ||
|  | #               3 - the character to pad with (default '-') | ||
|  | #      RETURNS: Nothing | ||
|  | #=============================================================================== | ||
|  | pad () { | ||
|  |     local text=${1?Usage: pad text [length] [character]} | ||
|  |     local length=${2:-80} | ||
|  |     local char=${3:--} | ||
|  | 
 | ||
|  |     local line | ||
|  |     printf -v line "%0*d%s\n" $((length - ${#text})) 0 "$text" | ||
|  |     char=${char:0:1} | ||
|  |     echo "${line//0/$char}" | ||
|  | } | ||
|  | 
 | ||
|  | #===  FUNCTION  ================================================================ | ||
|  | #         NAME: read_value | ||
|  | #  DESCRIPTION: Read a value from STDIN and handle errors. | ||
|  | #   PARAMETERS: 1 - Prompt string for the read | ||
|  | #               2 - Name of variable to receive the result | ||
|  | #               3 - Default value (optional) | ||
|  | #      RETURNS: 1 on error, otherwise 0 | ||
|  | #=============================================================================== | ||
|  | read_value () { | ||
|  |     local prompt="${1:?Usage: read_value prompt outputname [default]}" | ||
|  |     local outputname="${2:?Usage: read_value prompt outputname [default]}" | ||
|  |     local default="${3:-}" | ||
|  |     local var | ||
|  | 
 | ||
|  |     # | ||
|  |     # Make an option for the 'read' if there's a default | ||
|  |     # | ||
|  |     if [[ -n $default ]]; then | ||
|  |         default="-i '$default'" | ||
|  |     fi | ||
|  | 
 | ||
|  |     # | ||
|  |     # Read and handle CTRL-D (EOF). Use 'eval' to deal with the argument being | ||
|  |     # a variable | ||
|  |     # | ||
|  |     eval "read -r -e $default -p '$prompt' var" | ||
|  |     res="$?" | ||
|  |     if [[ $res -ne 0 ]]; then | ||
|  |         echo "Read aborted" | ||
|  |         return 1 | ||
|  |     fi | ||
|  | 
 | ||
|  |     # | ||
|  |     # Return the value in the nominated variable | ||
|  |     # | ||
|  |     eval "$outputname='$var'" | ||
|  |     return 0 | ||
|  | } | ||
|  | 
 | ||
|  | #===  FUNCTION  ================================================================ | ||
|  | #         NAME: define_colours | ||
|  | #  DESCRIPTION: Defines terminal colours | ||
|  | #   PARAMETERS: None | ||
|  | #      RETURNS: Nothing; justs sets the variables in the namespace | ||
|  | #=============================================================================== | ||
|  | define_colours () { | ||
|  | 
 | ||
|  |     # | ||
|  |     # Colour codes | ||
|  |     # | ||
|  |     red=$(tput setaf 1) | ||
|  |     export red | ||
|  |     green=$(tput setaf 2) | ||
|  |     export green | ||
|  |     yellow=$(tput setaf 3) | ||
|  |     export yellow | ||
|  |     blue=$(tput setaf 4) | ||
|  |     export blue | ||
|  |     purple=$(tput setaf 5) | ||
|  |     export purple | ||
|  |     reset=$(tput sgr0) | ||
|  |     export reset | ||
|  | 
 | ||
|  |     return | ||
|  | } | ||
|  | 
 | ||
|  | #===  FUNCTION  ================================================================ | ||
|  | #         NAME: undefine_colours | ||
|  | #  DESCRIPTION: Remove all the colour codes from the colour variables | ||
|  | #   PARAMETERS: None | ||
|  | #      RETURNS: Nothing; justs sets the variables in the namespace | ||
|  | #=============================================================================== | ||
|  | undefine_colours () { | ||
|  | 
 | ||
|  |     # | ||
|  |     # Colour codes being removed | ||
|  |     # | ||
|  |     for code in red green yellow blue purple reset; do | ||
|  |         eval "$code=''" | ||
|  |         eval "export $code" | ||
|  |     done | ||
|  | 
 | ||
|  |     return | ||
|  | } | ||
|  | 
 | ||
|  | #===  FUNCTION  ================================================================ | ||
|  | #         NAME: coloured | ||
|  | #  DESCRIPTION: Write a message with colour codes | ||
|  | #   PARAMETERS: 1 - colour name | ||
|  | #               2 - message | ||
|  | #      RETURNS: Nothing | ||
|  | #=============================================================================== | ||
|  | coloured () { | ||
|  |     local colour="${1:-green}" | ||
|  |     local message="${2:-no message}" | ||
|  | 
 | ||
|  |     printf '%s%s%s\n' "${!colour}" "$message" "${reset}" | ||
|  | } | ||
|  | 
 | ||
|  | #===  FUNCTION  ================================================================ | ||
|  | #         NAME: plural | ||
|  | #  DESCRIPTION: Adds an 's' to a word depending on the size of a number (based | ||
|  | #               on an example from O'Reilly). Also look at ngettext for a much | ||
|  | #               more sophisticated alternative. | ||
|  | #   PARAMETERS: 1 - the word to pluralise | ||
|  | #               2 - the number used to decide | ||
|  | #      RETURNS: Nothing | ||
|  | #=============================================================================== | ||
|  | plural () { | ||
|  |     if [[ $2 -eq 1 || $2 -eq -1 ]]; then | ||
|  |         echo "${1}" | ||
|  |     else | ||
|  |         echo "${1}s" | ||
|  |     fi | ||
|  | } | ||
|  | 
 | ||
|  | #===  FUNCTION  ================================================================ | ||
|  | #         NAME: trimpath | ||
|  | #  DESCRIPTION: Trim a file path to its last few components for display | ||
|  | #   PARAMETERS: $1 - path to trim | ||
|  | #               $2 - number of elements to retain | ||
|  | #      RETURNS: Trimmed path | ||
|  | #=============================================================================== | ||
|  | trimpath () { | ||
|  |     local path=${1:?Usage: mpath path elements} | ||
|  |     local elements=${2:?Usage: mpath path elements} | ||
|  |     local -a arr1 arr2 | ||
|  |     local result | ||
|  | 
 | ||
|  |     # Split the path | ||
|  | #     oldifs="$IFS" | ||
|  | #     IFS='/' mapfile -d'/' -t arr1 <<<"$path" | ||
|  |     IFS='/' read -r -a arr1 <<<"$path" | ||
|  | #     IFS="$oldifs" | ||
|  | 
 | ||
|  |     if [[ ${#arr1[@]} -gt $elements ]]; then | ||
|  |         # Put the last elements in another array | ||
|  |         mapfile -t arr2 < <(printf '%s\n' "${arr1[@]: -$elements}") | ||
|  | 
 | ||
|  |         # Return the second array interleaved with '/' | ||
|  |         result="${arr2[*]/%//}" | ||
|  |         result="${result//\/ /\/}" | ||
|  |         echo "${result:0:-1}" | ||
|  |     else | ||
|  |         echo "$path" | ||
|  |     fi | ||
|  | } | ||
|  | 
 | ||
|  | #=============================================================================== | ||
|  | #         NAME: stampfile | ||
|  | #  DESCRIPTION: Rename a file by adding a timestamp to its name. The timestamp | ||
|  | #               is the modification time. It is added at the end by default or | ||
|  | #               wherever the caller places a '%s'. Note there are not enough | ||
|  | #               error checks to deal with really weird requests :-) | ||
|  | #   PARAMETERS: $1 - name of file to rename | ||
|  | #               $2 - optional template string | ||
|  | #      RETURNS: Nothing | ||
|  | #=============================================================================== | ||
|  | function stampfile () { | ||
|  |     if [[ $# = 0  || $# -gt 2 ]]; then | ||
|  |         echo "Usage: ${FUNCNAME[0]} filename [template]" | ||
|  |         return | ||
|  |     fi | ||
|  |     local fname=${1} | ||
|  |     local tp=${2:-"${fname}_%s"} | ||
|  |     [ -e "$fname" ] || { echo "$fname does not exist"; return; } | ||
|  |     # shellcheck disable=SC2059 | ||
|  |     new=$(printf "$tp" "$(date -r "$fname" +%Y%m%d_%H%M%S)") | ||
|  |     mv "$fname" "$new" || { echo "Unable to mv $fname to $new"; return; } | ||
|  |     echo "Renamed $fname to $new" | ||
|  | } | ||
|  | 
 | ||
|  | # | ||
|  | # vim: syntax=sh:ts=8:sw=4:et:tw=78:fo=tcrqn21 |