fix_perms

#!/bin/bash

## Bash settings
set -uo pipefail

## Script globals
script_name=$(basename "${BASH_SOURCE[0]}")
script_dir=$({ cd "$(dirname "${BASH_SOURCE[0]}")" || { echo "Failed to access script file directory" >&2; exit; } } && pwd)
script_dir_abs=$({ cd "$(dirname "${BASH_SOURCE[0]}")" || { echo "Failed to access script file directory" >&2; exit; } } && pwd -P)
script_file="${script_dir}/${script_name}"
if [ -L "${BASH_SOURCE[0]}" ]; then
    script_file_abs=$(readlink "${BASH_SOURCE[0]}")
else
    script_file_abs="${script_dir_abs}/${script_name}"
fi
export CURRENT_PARENT_BASH_SCRIPT_FILE="$script_file"
script_args=("$@")

## Script imports
lib_dir="${script_dir}/../lib"
bash_functions_script="${lib_dir}/bash_script_func.sh"

## Source imports
source "$bash_functions_script"


## Arguments
octal_perms=''
chmod_mode_choices=(  'add' 'set' 'remove' )
chmod_mode_operator_arr=(  '+'   '='    '-'    )
chmod_mode='set'
sticky_arg_choices=( 'off' 'files' 'folders' 'all' )
add_group_s='off'  # typical default may be 'folders'
remove_group_s='off'  # typical default may be 'files'
add_user_s='off'
remove_user_s='off'
add_file_x=false
remove_file_x=false
namepat_arr=()
identify=false
dryrun=false
fwd_args_arr=()
srcpath_arr=()

## Custom globals
find_type_arg_val=''


## Script usage
read -r -d '' script_usage << EOM
Usage: ${script_name} [OPTION]... OCTAL_PERMS PATH... ['find' OPTION]...

  Run 'chmod' recursively on one or more directories (or files),
applying regular chmod octol permission settings.
  Where normally 'chmod -R 775 <dir>' would give all files
and folders within the directory executable permission,
this script will convert the octal setting to a long-form
setting that only makes folders and NOT files executable.
  Additionally, 'find' arguments may be provided to apply
permission changes more selectively than 'chmod -R'.
Provide the --dryrun option to first see what command will be
run under the hood without executing. Provide the --identify
option to list the files/folders that would have their perms
changed in a normal non-identify run.

Options:
 -m,--mode={$(string_join '|' "${chmod_mode_choices[@]}")} (default=${chmod_mode})
        How 'chmod' should apply permission changes.
    --add-file-x
        Add execute permissions to files when an applicable
        OCTAL_PERMS setting is provided.
        By default, only folders are given execute perms.
    --remove-file-x
        Remove all execute permissions from files.
    --add-group-s={$(string_join '|' "${sticky_arg_choices[@]}")} (default=${add_group_s})
        Set the 'setgid' attribute for folders/files.
          For folders, having the 'setgid' attribute set means
        that new files/subfolders created within will be
        automatically assigned to the same group as the parent
        directory, rather than the default ("primary") group of
        the user who created the file/subfolder.
          For executable files, having the 'setgid' attribute
        set means that any user who is able to execute the file
        will automatically execute the file with the privileges
        of the file's group (even if the user is not part of
        the file's group).
    --remove-group-s={$(string_join '|' "${sticky_arg_choices[@]}")} (default=${remove_group_s})
        Unset the 'setgid' attribute for files/folders.
    --add-user-s={$(string_join '|' "${sticky_arg_choices[@]}")} (default=${add_user_s})
        Set the 'setuid' attribute for files/folders.
          For executable files, having the 'setuid' attribute
        set means that any user who is able to execute the file
        will automatically execute the file with the privileges
        of the file's owner.
          For folders, having the 'setuid' attribute set typically
        means nothing on most UNIX and Linux systems, but may be
        interpreted on some systems to automatically assign new
        files/subfolders created within to the owner of the
        parent folder.
    --remove-user-s={$(string_join '|' "${sticky_arg_choices[@]}")} (default=${remove_user_s})
        Unset the 'setuid' attribute for files/folders.
 -n,--name=<pattern>
        Include files/dirs that match this pattern.
        This option can be provided multiple times to include
        multiple file patterns.
 -i,--identify
        Print file/directory paths identified by 'find' commands,
        but don't execute permission changes.
-db,--debug
-dr,--dryrun
        Print command used to modify file/folder permissions,
        without executing.
EOM
if (( $# < 1 )); then
    echo_e "$script_usage"
    exit_script_with_status 1
fi


## Parse arguments
set +u
parsing_fwd_args=false
while (( $# > 0 )); do
    arg="$1"

    if [ "$parsing_fwd_args" = true ]; then
        # Accept critical script optional arguments
        # specified at end of command.
        is_fwd_arg=true
        if [ "$(string_startswith "$arg" '-')" = true ]; then
            arg_opt="$(string_lstrip "$arg" '-')"
            is_fwd_arg=false
            if [ "$arg_opt" = 'h' ] || [ "$arg_opt" = 'help' ]; then
                arg_opt_nargs=0
                echo "$script_usage"
                exit 0
            elif [ "$arg_opt" = 'dr' ] || [ "$arg_opt" = 'dryrun' ]; then
                dryrun=true
            else
                is_fwd_arg=true
                if [ "$(string_contains "$arg_opt" '=')" = true ]; then
                    arg_val=$(printf '%s' "${arg_opt#*=}" | sed -r -e "s|^['\"]+||" -e "s|['\"]+$||")
                    arg_opt="${arg_opt%%=*}"
                else
                    arg_val="$2"
                fi
#                if [ "$arg_opt" = 'type' ] && [ "$arg_val" = 'd' ]; then
#                if [ "$arg_opt" = 'type' ] && [ "$arg_val" = 'f' ]; then
                if [ "$arg_opt" = 'type' ]; then
                    find_type_arg_val="$arg_val"
                fi
            fi
        fi
        if [ "$is_fwd_arg" = true ]; then
            if [ "$(string_contains "$arg" '*')" = true ] || [ "$(string_contains "$arg" ' ')" = true ]; then
                arg="'${arg}'"
            fi
            fwd_args_arr+=( "$arg" )
        fi

    elif [ "$(string_startswith "$arg" '-')" = false ]; then
        if [ -z "$octal_perms" ]; then
            octal_perms="$arg"
        else
            srcpath_arr+=( "$arg" )
        fi

    else
        arg_opt="$(string_lstrip "$arg" '-')"
        arg_opt_nargs=''
        if [ "$(string_contains "$arg_opt" '=')" = true ]; then
            arg_val=$(printf '%s' "${arg_opt#*=}" | sed -r -e "s|^['\"]+||" -e "s|['\"]+$||")
            arg_opt="${arg_opt%%=*}"
            arg_opt_nargs_do_shift=false
        else
            arg_val="$2"
            arg_opt_nargs_do_shift=true
        fi
        arg_val_can_start_with_dash=false

        if [ "$arg_opt" = 'h' ] || [ "$arg_opt" = 'help' ]; then
            arg_opt_nargs=0
            echo "$script_usage"
            exit 0

        elif [ "$arg_opt" = 'm' ] || [ "$arg_opt" = 'mode' ]; then
            arg_opt_nargs=1
            chmod_mode="$arg_val"

        elif [ "$arg_opt" = 'add-file-x' ]; then
            arg_opt_nargs=0
            add_file_x=true

        elif [ "$arg_opt" = 'remove-file-x' ]; then
            arg_opt_nargs=0
            remove_file_x=true

        elif [ "$arg_opt" = 'add-group-s' ]; then
            arg_opt_nargs=1
            add_group_s="$arg_val"

        elif [ "$arg_opt" = 'remove-group-s' ]; then
            arg_opt_nargs=1
            remove_group_s="$arg_val"

        elif [ "$arg_opt" = 'add-user-s' ]; then
            arg_opt_nargs=1
            add_user_s="$arg_val"

        elif [ "$arg_opt" = 'remove-user-s' ]; then
            arg_opt_nargs=1
            remove_user_s="$arg_val"

        elif [ "$arg_opt" = 'n' ] || [ "$arg_opt" = 'name' ]; then
            arg_opt_nargs=1
            namepat_arr+=( "$arg_val" )

        elif [ "$arg_opt" = 'i' ] || [ "$arg_opt" = 'identify' ]; then
            arg_opt_nargs=0
            identify=true

        elif [ "$arg_opt" = 'db' ] || [ "$arg_opt" = 'debug' ]; then
            arg_opt_nargs=0
            dryrun=true

        elif [ "$arg_opt" = 'dr' ] || [ "$arg_opt" = 'dryrun' ]; then
            arg_opt_nargs=0
            dryrun=true

        else
            arg_opt_nargs=0

            if (( ${#srcpath_arr[@]} >= 1 )); then
                parsing_fwd_args=true
                continue
            else
                echo_e "Unexpected argument: ${arg}"
                exit_script_with_status 1
            fi
        fi

        if [ -z "$arg_opt_nargs" ]; then
            echo_e "Developer error! "'$arg_opt_nargs'" was not set for argument: ${arg}"
            exit_script_with_status 1
        fi

        if [ "$arg_opt_nargs_do_shift" = true ] && (( arg_opt_nargs >= 1 )); then
            for arg_num in $(seq 1 $arg_opt_nargs); do
                shift
                arg_val="$1"
                if [ -z "$arg_val" ]; then
                    echo_e "Missing expected value (#${arg_num}) for argument: ${arg}"
                    exit_script_with_status 1
                elif [ "$arg_val_can_start_with_dash" = false ] && [ "$(string_startswith "$arg_val" '-')" = true ]; then
                    echo_e "Unexpected argument value: ${arg} ${arg_val}"
                    exit_script_with_status 1
                fi
            done
        fi
    fi

    shift
done
set -u


## Validate arguments

if [ "$(string_is_posint_or_zero "$octal_perms")" = true ] && { (( ${#octal_perms} == 3 )) || (( ${#octal_perms} == 4 )); }; then
    :
else
    echo_e "OCTAL_PERMS must be a 3-digit (or 4-digit) octal number (accepted by 'chmod')"
    exit_script_with_status 1
fi

if [ "$(itemOneOf "$chmod_mode" "${chmod_mode_choices[@]}")" = false ]; then
    echo_e "--mode must be one of the following: ${chmod_mode_choices[*]}"
    exit_script_with_status 1
fi

if [ "$(itemOneOf "$add_group_s" "${sticky_arg_choices[@]}")" = false ]; then
    echo_e "--add-group-s must be one of the following: ${sticky_arg_choices[*]}"
    exit_script_with_status 1
fi
if [ "$(itemOneOf "$remove_group_s" "${sticky_arg_choices[@]}")" = false ]; then
    echo_e "--remove-group-s must be one of the following: ${sticky_arg_choices[*]}"
    exit_script_with_status 1
fi
if [ "$(itemOneOf "$add_user_s" "${sticky_arg_choices[@]}")" = false ]; then
    echo_e "--add-user-s must be one of the following: ${sticky_arg_choices[*]}"
    exit_script_with_status 1
fi
if [ "$(itemOneOf "$add_user_s" "${sticky_arg_choices[@]}")" = false ]; then
    echo_e "--remove-user-s must be one of the following: ${sticky_arg_choices[*]}"
    exit_script_with_status 1
fi

if [ "$add_file_x" = true ] && [ "$remove_file_x" = true ]; then
    echo_e "--set-file-x and --unset-file-x options conflict"
    exit_script_with_status 1
fi
if [ "$add_group_s" != 'off' ] && [ "$remove_group_s" != 'off' ] \
    && { [ "$add_group_s" = "$remove_group_s" ] || [ "$add_group_s" = 'all' ] || [ "$remove_group_s" = 'all' ]; }; then
    echo_e "--add-group-s and --remove-group-s options conflict"
    exit_script_with_status 1
fi
if [ "$add_user_s" != 'off' ] && [ "$remove_user_s" != 'off' ] \
    && { [ "$add_user_s" = "$remove_user_s" ] || [ "$add_user_s" = 'all' ] || [ "$remove_user_s" = 'all' ]; }; then
    echo_e "--add-user-s and --remove-user-s options conflict"
    exit_script_with_status 1
fi

if (( ${#srcpath_arr[@]} == 0 )); then
    echo_e "At least one source path argument must be provided"
    exit_script_with_status 1
fi
for srcpath in "${srcpath_arr[@]}"; do
    if [ ! -e "$srcpath" ]; then
        echo_e "Source path does not exist: ${srcpath}"
        exit_script_with_status 1
    fi
done


# Build -name arguments to give to 'find' command
find_name_args=''
if (( ${#namepat_arr[@]} > 0 )); then
    find_name_args="\("
    for i in "${!namepat_arr[@]}"; do
        if (( i == 0 )); then
            find_name_args="${find_name_args} -name '${namepat_arr[i]}'"
        else
            find_name_args="${find_name_args} -o -name '${namepat_arr[i]}'"
        fi
    done
    find_name_args="${find_name_args} \)"
fi
find_args="${fwd_args_arr[*]+${fwd_args_arr[*]}} ${find_name_args}"
find_args=$(string_strip "$find_args")


# Handle 4-digit OCTAL_PERMS
provided_octal_perms="$octal_perms"
if (( ${#octal_perms} == 4 )); then
    octal_perms="${octal_perms:1:3}"
fi

# Convert octal permission setting to RWX format
chmod_perms_from_octal=''
i_chmod_mode=$(indexOf "$chmod_mode" "${chmod_mode_choices[@]}")
chmod_mode_operator="${chmod_mode_operator_arr[$i_chmod_mode]}"
for (( i=0; i<${#octal_perms}; i++ )); do
    octal_digit="${octal_perms:$i:1}"
    if (( i == 0 )); then
        perm_group='u'
    elif (( i == 1 )); then
        perm_group='g'
    elif (( i == 2 )); then
        perm_group='o'
    fi
    octal_rwx=$(chmod_octal_digit_to_rwx "$octal_digit")
    if [ -z "$octal_rwx" ] && [ "$chmod_mode_operator" != '=' ]; then
        :
    else
        chmod_perms_from_octal="${chmod_perms_from_octal},${perm_group}${chmod_mode_operator}${octal_rwx}"
    fi
done
chmod_perms_from_octal=$(string_lstrip "$chmod_perms_from_octal" ',')
if [ "$add_file_x" = false ]; then
    chmod_perms_from_octal="${chmod_perms_from_octal//x/X}"
fi
chmod_perms_before_sticky="$chmod_perms_from_octal"

# Handle 4-digit OCTAL_PERMS
if (( ${#provided_octal_perms} == 4 )); then
    octal_first_digit="${octal_perms:0:1}"
    if (( octal_first_digit == 0 )); then
        :
    elif (( octal_first_digit == 2 )); then
        chmod_perms_from_octal="${chmod_perms_from_octal},g+s"
        if [ "$add_group_s" = 'off' ]; then
            add_group_s='folders'
        fi
    elif (( octal_first_digit == 4 )); then
        chmod_perms_from_octal="${chmod_perms_from_octal},u+s"
        if [ "$add_user_s" = 'off' ]; then
            add_user_s='files'
        fi
    elif (( octal_first_digit == 6 )); then
        chmod_perms_from_octal="${chmod_perms_from_octal},g+s"
        chmod_perms_from_octal="${chmod_perms_from_octal},u+s"
        if [ "$add_group_s" = 'off' ]; then
            add_group_s='folders'
        fi
        if [ "$add_user_s" = 'off' ]; then
            add_user_s='files'
        fi
    else
        echo_e "First digit in a 4-digit OCTAL_PERMS setting must be one of the following: 0 2 4 6"
        exit_script_with_status 1
    fi
fi


# Handle user/group sticky bit settings
chmod_perms_files="$chmod_perms_before_sticky"
chmod_perms_folders="$chmod_perms_before_sticky"
if [ "$remove_file_x" = true ]; then
    chmod_perms_files="${chmod_perms_files//x/}"
    chmod_perms_files="${chmod_perms_files//X/}"
fi
if [ "$add_user_s" != 'off' ]; then
    if [ "$add_user_s" = 'files' ] || [ "$add_user_s" = 'all' ]; then
        chmod_perms_files="${chmod_perms_files},u+s"
    fi
    if [ "$add_user_s" = 'folders' ] || [ "$add_user_s" = 'all' ]; then
        chmod_perms_folders="${chmod_perms_folders},u+s"
    fi
fi
if [ "$remove_user_s" != 'off' ]; then
    if [ "$remove_user_s" = 'files' ] || [ "$remove_user_s" = 'all' ]; then
        chmod_perms_files="${chmod_perms_files},u-s"
    fi
    if [ "$remove_user_s" = 'folders' ] || [ "$remove_user_s" = 'all' ]; then
        chmod_perms_folders="${chmod_perms_folders},u-s"
    fi
fi
if [ "$add_group_s" != 'off' ]; then
    if [ "$add_group_s" = 'files' ] || [ "$add_group_s" = 'all' ]; then
        chmod_perms_files="${chmod_perms_files},g+s"
    fi
    if [ "$add_group_s" = 'folders' ] || [ "$add_group_s" = 'all' ]; then
        chmod_perms_folders="${chmod_perms_folders},g+s"
    fi
fi
if [ "$remove_group_s" != 'off' ]; then
    if [ "$remove_group_s" = 'files' ] || [ "$remove_group_s" = 'all' ]; then
        chmod_perms_files="${chmod_perms_files},g-s"
    fi
    if [ "$remove_group_s" = 'folders' ] || [ "$remove_group_s" = 'all' ]; then
        chmod_perms_folders="${chmod_perms_folders},g-s"
    fi
fi


# Summarize permission settings to be applied
set_files_and_folders_separate=false
echo "Converted octal permission setting to 'chmod' setting: ${provided_octal_perms} -> ${chmod_perms_from_octal}"
if [ "$find_type_arg_val" = 'f' ]; then
    echo "Permission setting to be applied to files: ${chmod_perms_files}"
elif [ "$find_type_arg_val" = 'd' ]; then
    chmod_perms_folders="${chmod_perms_folders//X/x}"
    echo "Permission setting to be applied to folders: ${chmod_perms_folders}"
elif [ "$chmod_perms_files" != "$chmod_perms_folders" ]; then
    set_files_and_folders_separate=true
    chmod_perms_folders="${chmod_perms_folders//X/x}"
    echo
    echo "Two passes of the 'find' program will be used to set different perms for files and folders"
    echo "Permission setting for folders: ${chmod_perms_folders}"
    echo "Permission setting for files:   ${chmod_perms_files}"
else
    echo "Permission setting to be applied to files and folders: ${chmod_perms_files}"
fi
echo


## Main program

for srcpath in "${srcpath_arr[@]}"; do
    cmd2=''
    if [ -n "$find_args" ] || [ "$identify" = true ] || [ "$set_files_and_folders_separate" = true ]; then
        if [ "$identify" = true ]; then
            cmd1="find \"${srcpath}\" ${find_args}"
        elif [ "$find_type_arg_val" = 'f' ]; then
            cmd1="find \"${srcpath}\" ${find_args} -exec chmod ${chmod_perms_files} {} +"
        elif [ "$find_type_arg_val" = 'd' ]; then
            cmd1="find \"${srcpath}\" ${find_args} -exec chmod ${chmod_perms_folders} {} +"
        elif [ "$set_files_and_folders_separate" = true ]; then
            cmd1="find \"${srcpath}\" -type d ${find_args} -exec chmod ${chmod_perms_folders} {} +"
            cmd2="find \"${srcpath}\" -type f ${find_args} -exec chmod ${chmod_perms_files} {} +"
        else
            cmd1="find \"${srcpath}\" ${find_args} -exec chmod ${chmod_perms_files} {} +"
        fi
    else
        cmd1="chmod -R ${chmod_perms_files} \"${srcpath}\""
    fi

    echo "Fixing perms in ${srcpath}"

    if [ "$dryrun" = true ]; then
        echo "$cmd1"
        if [ -n "$cmd2" ]; then
            echo "$cmd2"
        fi
    else
        eval "$cmd1"
        if [ -n "$cmd2" ]; then
            eval "$cmd2"
        fi
    fi
done


if [ "$dryrun" = false ]; then
    echo "Done!"
fi