Initial import

Author: Wes Dean

shell_script_template.bash

@@ -0,0 +1,102 @@
+#!/usr/bin/env bash
+
+## @file shell_script_template.bash
+## @brief a quick sample script template
+## @details
+## This template gives us a few nice things to start with:
+##
+## 1. some Doxygen-style comments to start things off
+## 2. flags to protect us from undefined variables and failed commands
+## 3. a `SCRIPT_PATH` variable so we can reference where the script lives
+## 4. an error trap that prints the line where an error happens
+## 5. a stack dump when errors do happen
+## 6. a wrapper to allow us to source this script as if it was a library
+## 7. CLI parameter handling
+## 8. automagic help / usage generation
+## @author Wes Dean
+
+
+set -euo pipefail
+
+## @var SCRIPT_PATH
+## @brief path to where the script lives
+declare SCRIPT_PATH
+# shellcheck disable=SC2034
+SCRIPT_PATH="$(cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd -P)"
+
+## @var DEFAULT_WORD
+## @brief default value for the 'word' CLI parameter
+declare -i DEFAULT_WORD
+# shellcheck disable=SC2034
+DEFAULT_WORD="hello"
+
+
+
+## @fn die
+## @brief receive a trapped error and display helpful debugging details
+## @details
+## When called -- presumably by a trap -- die() will provide details
+## about what happened, including the filename, the line in the source
+## where it happened, and a stack dump showing how we got there.  It
+## will then exit with a result code of 1 (failure)
+## @retval 1 always returns failure
+## @par Example
+## @code
+## trap die ERR
+## @endcode
+die() {
+  printf "ERROR %s in %s AT LINE %s\n" "$?" "${BASH_SOURCE[0]}" "${BASH_LINENO[0]}" 1>&2
+
+  local i=0
+  local FRAMES=${#BASH_LINENO[@]}
+
+  # FRAMES-2 skips main, the last one in arrays
+  for ((i=FRAMES - 2; i >= 0; i--)); do
+    printf "  File \"%s\", line %s, in %s\n" "${BASH_SOURCE[i + 1]}" "${BASH_LINENO[i]}" "${FUNCNAME[i + 1]}"
+    # Grab the source code of the line
+    sed -n "${BASH_LINENO[i]}{s/^/    /;p}" "${BASH_SOURCE[i + 1]}"
+  done
+  exit 1
+}
+
+trap die ERR
+
+
+## @par Example
+## @code
+## # set values from their defaults
+## word="${DEFAULT_WORD}"
+##
+## # process long options
+## for arg in "$@" ; do
+##   shift
+##   case "$arg" in
+##     '--word') set -- "$@" "-w" ;;
+##     '--help') set -- "$@" "-h" ;;
+##     *)        set -- "$@" "$arg" ;;
+##   esac
+## done
+##
+## # process short options
+## OPTIND=1
+## while getopts "w:h" opt ; do
+##   case "$opt" in
+##     'w') word="$OPTARG" ;;
+##     'h') display_usage ; exit 0 ;;
+##     *) echo "Invalid option" ; display_usage ; exit 1 ;;
+##   esac
+## done
+##
+## shift "$((OPTIND - 1))
+##
+## # Process positional arguments
+## for file in "$@" ; do
+##   printf "%s" "$file"
+## done
+## @endcode
+
+
+
+
+[[ "$0" == "${BASH_SOURCE[0]}" ]] && main "$@"
+