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在 shell 脚本中将命名参数作为数组传递

tag-icon • tag-icon bash shell shell-script
在 shell 脚本中将命名参数作为数组传递

我当前正在构建的工具中有以下代码：

while [ $# -gt 0 ]; do
  case "$1" in
    --var1=*)
      var1="${1#*=}"
      ;;
    --var2=*)
      var1="${1#*=}"
      ;;
    --var3=*)
      var1="${1#*=}"
      ;;
    *)
      printf "***************************\n
              * Error: Invalid argument.*\n
              ***************************\n"
  esac
  shift
done

我有很多选项要添加，但其中五个选项应保存为数组。因此，如果我从 shell 调用该工具，可以使用如下所示的命令：
./tool --var1="2" --var1="3" --var1="4" --var1="5" --var2="6" --var3="7"

如何将 的值保存var1为数组？那可能吗？如果是这样，如果我有太多数组，从效率角度来看，处理这些数组的最佳方法是什么？

答案1

如果在 Linux 上（util-linux已getopt安装实用程序，或来自 的实用程序busybox），您可以执行以下操作：

declare -A opt_spec
var1=() var2=() var4=false
unset var3
opt_spec=(
  [opt1:]='var1()' # opt with argument, array variable
  [opt2:]='var2()' # ditto
  [opt3:]='var3'   # opt with argument, scalar variable
  [opt4]='var4'    # boolean opt without argument
)
parsed_opts=$(
  IFS=,
  getopt -o + -l "${!opt_spec[*]}" -- "$@"
) || exit
eval "set -- $parsed_opts"
while [ "$#" -gt 0 ]; do
  o=$1; shift
  case $o in
    (--) break;;
    (--*)
      o=${o#--}
      if ((${opt_spec[$o]+1})); then # opt without argument
        eval "${opt_spec[$o]}=true"
      else
        o=$o:
        case "${opt_spec[$o]}" in
          (*'()') eval "${opt_spec[$o]%??}+=(\"\$1\")";;
          (*) eval "${opt_spec[$o]}=\$1"
        esac
        shift
      fi
  esac
done
echo "var1: ${var1[@]}"

这样，您就可以将脚本称为：

my-script --opt1=foo --opt2 bar --opt4 -- whatever

--getopt 将为您完成解析、处理和缩写的艰苦工作。

或者，您可以依赖变量的类型，而不是在$opt_spec关联数组定义中指定它：

declare -A opt_spec
var1=() var2=() var4=false
unset var3
opt_spec=(
  [opt1:]=var1   # opt with argument
  [opt2:]=var2   # ditto
  [opt3:]=var3   # ditto
  [opt4]=var4    # boolean opt without argument
)
parsed_opts=$(
  IFS=,
  getopt -o + -l "${!opt_spec[*]}" -- "$@"
) || exit
eval "set -- $parsed_opts"
while [ "$#" -gt 0 ]; do
  o=$1; shift
  case $o in
    (--) break;;
    (--*)
      o=${o#--}
      if ((${opt_spec[$o]+1})); then # opt without argument
        eval "${opt_spec[$o]}=true"
      else
        o=$o:
        case $(declare -p "${opt_spec[$o]}" 2> /dev/null) in
          ("declare -a"*) eval "${opt_spec[$o]}+=(\"\$1\")";;
          (*) eval "${opt_spec[$o]}=\$1"
        esac
        shift
      fi
  esac
done
echo "var1: ${var1[@]}"

您可以添加简短选项，例如：

declare -A long_opt_spec short_opt_spec
var1=() var2=() var4=false
unset var3
long_opt_spec=(
  [opt1:]=var1   # opt with argument
  [opt2:]=var2   # ditto
  [opt3:]=var3   # ditto
  [opt4]=var4    # boolean opt without argument
)
short_opt_spec=(
  [a:]=var1
  [b:]=var2
  [c]=var3
  [d]=var4
)
parsed_opts=$(
  IFS=; short_opts="${!short_opt_spec[*]}"
  IFS=,
  getopt -o "+$short_opts" -l "${!long_opt_spec[*]}" -- "$@"
) || exit
eval "set -- $parsed_opts"
while [ "$#" -gt 0 ]; do
  o=$1; shift
  case $o in
    (--) break;;
    (--*)
      o=${o#--}
      if ((${long_opt_spec[$o]+1})); then # opt without argument
        eval "${long_opt_spec[$o]}=true"
      else
        o=$o:
        case $(declare -p "${long_opt_spec[$o]}" 2> /dev/null) in
          ("declare -a"*) eval "${long_opt_spec[$o]}+=(\"\$1\")";;
          (*) eval "${long_opt_spec[$o]}=\$1"
        esac
        shift
      fi;;
    (-*)
      o=${o#-}
      if ((${short_opt_spec[$o]+1})); then # opt without argument
        eval "${short_opt_spec[$o]}=true"
      else
        o=$o:
        case $(declare -p "${short_opt_spec[$o]}" 2> /dev/null) in
          ("declare -a"*) eval "${short_opt_spec[$o]}+=(\"\$1\")";;
          (*) eval "${short_opt_spec[$o]}=\$1"
        esac
        shift
      fi
  esac
done
echo "var1: ${var1[@]}"

答案2

我建议你看看我的通用 Shell 脚本 GitHub：utility_functions.sh。在那里你会看到一个名为的函数获取参数。它旨在将选项和值关联起来。

我仅在此处粘贴该函数，但它取决于该脚本中的其他几个函数

##########################
#
#   Function name: getArgs
#
#   Description:
#       This function provides the getopts functionality
#   while allowing the use of long operations and list of parameters.
#   in the case of a list of arguments for only one option, this list
#   will be returned as a single-space-separated list in one single string.
#
#   Pre-reqs:
#       None
#
#   Output:
#       GA_OPTION variable will hold the current option
#       GA_VALUE variable will hold the value (or list of values) associated
#           with the current option
#   
#   Usage:
#       You have to source the function in order to be able to access the GA_OPTIONS
#   and GA_VALUES variables
#       . getArgs $*
#
####################
function getArgs {

    # Variables to return the values out of the function
    typeset -a GA_OPTIONS
    typeset -a GA_VALUES

    # Checking for number of arguments
    if [[ -z $1 ]]
    then
        msgPrint -warning "No arguments found"
        msgPrint -info "Please call this function as follows: . getArgs \$*"
        exit 0
    fi

    # Grab the dash
    dash=$(echo $1 | grep "-")
    # Looking for short (-) or long (--) options
    isOption=$(expr index "$dash" "-")
    # Initialize the counter
    counter=0
    # Loop while there are arguments left
    while [[ $# -gt 0 ]]
    do
        if [[ $dash && $isOption -eq 1 ]]
        then
            (( counter+=1 ))
            GA_OPTIONS[$counter]=$1
            shift
        else
            if [[ -z ${GA_VALUES[$counter]} ]]
            then
                GA_VALUES[$counter]=$1
            else
                GA_VALUES[$counter]="${GA_VALUES[$counter]} $1"
            fi
            shift
        fi
        dash=$(echo $1 | grep "-")
        isOption=$(expr index "$dash" "-")
    done
    # Make the variables available to the main algorithm
    export GA_OPTIONS
    export GA_VALUES

    msgPrint -debug "Please check the GA_OPTIONS and GA_VALUES arrays for options and arguments"
    # Exit with success
    return 0
}

如您所见，此特定函数将导出 GA_OPTIONS 和 GA_VALUES。唯一的条件是值必须是选项后面以空格分隔的列表。

您可以将该脚本称为 ./tool --var1 2 3 4 5 --var2="6" --var3="7"

或者只是使用类似的逻辑来适应您的偏好。

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