#!/bin/bash
-
# Desc: Checks that a valid tar archive exists, creates one otherwise
-
+#===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
-
-#===BEGIN Declare local script functions===
checkMakeTar() {
# Desc: Checks that a valid tar archive exists, creates one otherwise
# Usage: checkMakeTar [ path ]
+ # Version: 1.0.2
# Input: arg1: path of tar archive
- # Output: exit code 0 (even if tar had to be created)
- # Depends: try, tar, date
- local PATH_TAR="$1"
+ # Output: exit code 0 : tar readable
+ # exit code 1 : tar missing; created
+ # exit code 2 : tar not readable; moved; replaced
+ # Depends: bash 5, date 8, tar 1, try()
+ local pathTar returnFlag0 returnFlag1 returnFlag2
+ pathTar="$1";
# Check if file is a valid tar archive
- if tar --list --file="$PATH_TAR" 1>/dev/null 2>&1; then
+ if tar --list --file="$pathTar" 1>/dev/null 2>&1; then
## T1: return success
- return 0;
+ returnFlag0="tar valid";
else
## F1: Check if file exists
- if [[ -f "$PATH_TAR" ]]; then
+ if [[ -f "$pathTar" ]]; then
### T: Rename file
- try mv "$PATH_TAR" "$PATH_TAR""--broken--""$(date +%Y%m%dT%H%M%S)";
+ try mv "$pathTar" "$pathTar""--broken--""$(date +%Y%m%dT%H%M%S)" && \
+ returnFlag1="tar moved";
else
### F: -
:
- fi
+ fi;
## F2: Create tar archive, return 0
- try tar --create --file="$PATH_TAR" --files-from=/dev/null;
+ try tar --create --file="$pathTar" --files-from=/dev/null && \
+ returnFlag2="tar created";
+ fi;
+
+ # Determine function return code
+ if [[ "$returnFlag0" = "tar valid" ]]; then
return 0;
- fi
+ elif [[ "$returnFlag2" = "tar created" ]] && ! [[ "$returnFlag1" = "tar moved" ]]; then
+ return 1; # tar missing so created
+ elif [[ "$returnFlag2" = "tar created" ]] && [[ "$returnFlag1" = "tar moved" ]]; then
+ return 2; # tar not readable so moved; replaced
+ fi;
} # checks if arg1 is tar; creates one otherwise
#===END Declare local script functions===
#====BEGIN sample code====
-myFile="/tmp/$(date +%s)..tar"
-yell "$myFile doesn't yet exist."
+#myFile="/tmp/$(date +%s)..tar"
+myFile="/tmp/$(date +%Y%m%d).tar"
+if [[ -f "$myFile" ]]; then yell "$myFile already exists."; else yell "$myFile doesn't yet exist."; fi
if checkMakeTar "$myFile"; then
yell "checkMakeTar() function run and exited:$?";
else
ls -l "$myFile";
fi
#====END sample code====
+
+# Author: Steven Baltakatei Sandoval
+# License: GPLv3+