util-functions.sh

sub_var_text() {
  local variable=$1
  
  read -r -d '' VAR <<-EOT
    text also with $variable inside\n
EOT
  printf "$VAR"
}

# function change_ifs()
# change the default field seperator
#   usage: change_ifs ":"
change_ifs(){
  new_ifs=$1
  OLDIFS="${IFS}"
  export OLDIFS
  IFS=$new_ifs
  return
}

# function revert_ifs()
# revert the default field seperator
# Automatically reverts to latest change.
# As such use with caution.
#   usage: revert_ifs
revert_ifs(){
  IFS=$OLDIFS
  return
}
  # If it is a function name it is then executed with all the values passed with

execute_function() {
  local func="$1"
  shift
    if [[ ${func:-} ]] && declare -F | cut -d' ' -f3 | fgrep -qx -- "${func:-}"; then
      func "${@}"
      rc=$?
      return $rc
    else
      echo "Not a function ${@}"
    fi
}

# cmd: for_each "applies an operation to set of arguments one by one"
# ex. $(for_each 'grep mesos' `ls *.sh`)
for_each() {
	op=$1
	shift
	for arg in "$@"; do
	eval "$op" \"$arg\"
	done
}

cmd duplicates 'finds duplicate files. To follow symbolic links run duplicate -L $DIR'
duplicates()
{
	# Features:
	# Fast because checks sizes first
	# and filters same linked files by checking inode (%i)
	# - Sorts files by size to help you to delete biggest files first

	# Troubleshooting:
	# on out of memory define TMPDIR

	find "$@" -type f -not -regex '.*/\.svn/.*' -printf "%10i\t%10s\t%p\n" \
		| sort -n \
		| uniq --unique -w10 \
		| cut -f 2,3 | sort -n \
		| uniq --all-repeated -w 10 \
		| cut -f 2 \
		| perl -pe "s/\n/\0/g" \
		| xargs -0 -i{} sha1sum "{}" | sort \
		| uniq --all-repeated=separate -w32 | cut -d ' ' -f 3
}

# cmd: system_status_long "shows long system status and statistics by running various system utilities"
system_status_long() {
	grep "" /etc/issue /etc/*release
	top -bn1 | head --lines 20
	echo
	free -m
	echo
	iostat -m
	echo
	mpstat
	echo
	vmstat -S M -s
	echo
	df --all --human-readable
	echo
	lsblk
	echo
	lscpu
	echo
	lsusb
	echo
	lspci
	echo
	lshw -short
}

# cmd: system_status_short "shows short summary of system resources (RAM,CPU) usage"
system_status_short() {
	echo "Available RAM: "$((`mem_avail_kb`/1024))"M" \
	       	$((100*`mem_avail_kb`/`head -1</proc/meminfo | sed "s/ \+/ /g" | cut -d' ' -f 2`))"%"
	paste <(mpstat|grep %usr|sed "s/ \+/\n/g") <(mpstat|grep all|sed "s/ \+/\n/g") | \grep -e idle -e iowait -e sys
	ps-cpu
	ps-mem
}

# cmd: trap_err "traps command failures, print reuturn value and returns, better than set -o errexit"
trap_err() {
  trap 'echo -e $"\e[2;31mFAIL \e[0;39m ret=$? ${BASH_SOURCE[0]}:${LINENO}" > /dev/stderr;return 2> /dev/null' ERR
}

# cmd: repeat_cmd Repeat n times command. 
repeat_cmd() {
    local ii max
    max=$1; shift;
    for ((ii=1; i <= max ; ii++)); do
        eval "$@";
    done
}

# cmd: ff Find a file with a pattern in name:
ff() { find . -type f -iname '*'$*'*' -ls ; }

# cmd: fe \*.txt cat
# Find a file with pattern $1 in name and Execute $2 on it:
fe() { find . -type f -iname '*'${1:-}'*' -exec ${2:-file} {} \;  ; }