Rdoc - a command-line tool for launching documents (improved)

Question

A few days ago I posted a previous version of my first bash script here to get few tips and reviews so I could improve it. So now it is improved a bit. I also shellchecked it and fixed the warnings. I would love to hear more tips from you guys.

Here is the code:

#!/usr/bin/env bash
declare -r CONF_DIR_PATH="$HOME/.config/rdoc"
declare -r TMP_FILE="/tmp/rdoc_tmp.$$" 
#Trap the following signals and do cleanup before exiting 
trap 'rm -f "$TMP_FILE" 2> /dev/null && exit 0' EXIT 
trap 'rm -f "$TMP_FILE" 2> /dev/null && echo && exit 1' SIGINT
fn_generate_configs() {
 local doc_dir_path
 local pdf_viewer_name
 mkdir -p "$CONF_DIR_PATH"
 
 printf "Please enter your documents directory full path: "
 read -r doc_dir_path
 echo "$doc_dir_path" > "$CONF_DIR_PATH/doc_dir"
 printf "\nPlease enter your pdf's viewer name: "
 read -r pdf_viewer_name
 echo "$pdf_viewer_name" > "$CONF_DIR_PATH/pdf_viewer"
 printf "\nYour configurations were generated succesfully.\n"
}
fn_read_configs() {
 if ! doc_dir=$(cat "$CONF_DIR_PATH/doc_dir" 2> /dev/null); then
 echo Error: one or all of your configuration files are missing.
 echo Try -h for help.
 exit 1
 fi
 if ! pdf_viewer=$(cat "$CONF_DIR_PATH/pdf_viewer" 2> /dev/null); then
 echo Error: one or all of your configuration files are missing.
 echo Try -h for help.
 exit 1
 fi
}
fn_search_for_book() {
 local path
 local grep_opt="-q"
 local string_to_exclude="1ドル/"
 
 if [ "$i_status" -eq 1 ]; then 
 grep_opt="-qi"
 fi
 if [ "$r_status" -eq 1 ]; then #Search recursively 
 for path in "1ドル"/*; do 
 if [ -d "$path" ]; then 
 fn_search_for_book "$path"
 elif [ -f "$path" ]; then 
 #Redirect grep help message if book_name has the program's options value.
 #This would happen if the user called the program with the defualt behaviour,
 #plus with one of the available options but he/she omitted to pass the doc_name
 #so book_name will get the value of the passed options wich will trhow the grep help message.
 if echo "$path" | grep $grep_opt "$book_name" 2> /dev/null; then 
 echo "${path//"$string_to_exclude"/}" >> "$TMP_FILE"
 fi
 fi
 done
 else
 for path in "1ドル"/*; do
 if [ -f "$path" ]; then 
 #Redirect grep help message for the same reasons as above
 if echo "$path" | grep $grep_opt "$book_name" 2> /dev/null; then 
 echo "${path//"$string_to_exclude"/}" >> "$TMP_FILE"
 fi
 fi
 done
 fi
}
fn_display_books() {
 local doc
 local founded_docs
 
 #Make sure a book was founded and TMP_FILE was generated
 if ! founded_docs=$(cat "$TMP_FILE" 2> /dev/null); then 
 printf "Error: no document was found with \'%s\' in it.\n" "$book_name"
 exit 1
 fi
 printf "These are the documents that were found:\n\n"
 #Set output's color to red
 tput setaf 1
 
 for doc in $founded_docs; do 
 echo "$doc"
 done
 #Reset output's color 
 tput sgr0 
}
fn_count_books() {
 local doc
 local founded_docs
 local cnt=0
 if ! founded_docs=$(cat "$TMP_FILE" 2> /dev/null); then
 printf "\nError: \'%s\' manipulation while the program is running are disallowed.\n" "$TMP_FILE"
 exit 1
 fi
 
 for doc in $founded_docs; do 
 (( cnt++ ))
 done
 return "$cnt"
}
fn_final_book_name() {
 printf "\nWhich one of them would you like to open: "
 read -r book_name
}
fn_generate_books_paths() {
 local path
 
 if [ "$r_status" -eq 1 ]; then
 for path in "1ドル"/*; do
 if [ -d "$path" ]; then
 fn_generate_books_paths "$path"
 elif [ -f "$path" ]; then
 echo "$path" >> "$TMP_FILE"
 fi
 done
 else 
 for path in "1ドル"/*; do
 if [ -f "$path" ]; then
 echo "$path" >> "$TMP_FILE"
 fi
 done
 fi
}
fn_get_book_path() {
 local founded_paths
 local path
 local grep_opt="-q"
 if ! founded_paths=$(cat "$TMP_FILE" 2> /dev/null); then
 printf "\nError: \'%s\' manipulation while the program is running are disallowed.\n" "$TMP_FILE"
 exit 1
 fi
 if [ "$i_status" -eq 1 ]; then
 grep_opt="-qi"
 fi
 for path in $founded_paths; do 
 if ! echo "$path" | grep $grep_opt "$book_name"; then 
 continue
 fi
 book_path="$path"
 break
 done
}
fn_open_book() {
 if ! "$pdf_viewer" "$book_path" 2> /dev/null; then 
 printf "\nError: %s can\'t be opened.\n" "$book_path" 
 exit 1
 fi
 printf "\nOpening: %s\n" "$book_path"
}
fn_help_message() {
printf "Usage: rdoc <options> [argument]
 
Available options: 
 -h Display this help message. 
 -g Generate new configuration files. 
 -r Allow recursive searching for the document. 
 -i Ignore case distinctions while searching for the document. 
 -s Search for the document and display results. 
 This option takes a document name or a part of it as an argument. 
 -o Search for the document, display results then open it using your pdf viewer. 
 This option takes a document name or a part of it as an argument. 
 (Default) 
NOTE: 
 When using '-s' or '-o' option in a combination of other options like this: 
 
 $ rdoc -ris document_name 
 
 Please make sure that it's the last option; to avoid unexpected behaviour.
" 
}
doc_dir=""
pdf_viewer=""
book_path=""
book_name=${!#} #book_name equals to the last arg by defualt so the default option ('-o') will work.
#Options status
r_status=0
i_status=0
s_status=0
o_status=1 #Make -o the default option 
#Display help message if no options were passed 
if [ $# -eq 0 ]; then
 fn_help_message
 exit 0
fi
while getopts ":hgris:o:" opt; do
 case $opt in 
 h)
 fn_help_message
 exit 0
 ;;
 g)
 fn_generate_configs
 o_status=0
 ;;
 r)
 r_status=1
 ;;
 i)
 i_status=1
 ;;
 s)
 book_name="$OPTARG"
 s_status=1
 o_status=0 
 ;;
 o)
 book_name="$OPTARG"
 ;;
 :)
 printf "Error: an argument is required for \'-%s\' option.\n" "$OPTARG"
 echo Try -h for help.
 exit 1
 ;;
 *)
 printf "Error: unknown option \'-%s\'.\n" "$OPTARG"
 echo Try -h for help.
 exit 1
 ;;
 esac
done
if [ "$s_status" -eq 1 ]; then
 fn_read_configs
 fn_search_for_book "$doc_dir"
 fn_display_books
elif [ "$o_status" -eq 1 ]; then 
 fn_read_configs
 fn_search_for_book "$doc_dir"
 fn_display_books
 fn_count_books
 if [ $? -gt 1 ]; then #If more than 1 book were found with $book_name in it
 fn_final_book_name
 #Clean any leftovers of $TMP_FILE to search properly
 rm "$TMP_FILE" 2> /dev/null
 #Make sure that the user chose an available document
 fn_search_for_book "$doc_dir"
 if [ ! -f "$TMP_FILE" ]; then 
 printf "\nError: no document was found with \'%s\' in it.\n" "$book_name"
 exit 1
 fi
 #Make sure that the user is specific enough about the book name
 fn_count_books
 if [ $? -gt 1 ]; then
 printf "\nError: More than 1 book was found with the name \'%s\' in it.\n" "$book_name"
 exit 1
 fi
 fi
 
 : > "$TMP_FILE" #Make sure $TMP_FILE is empty so it'll be usable in fn_generate_books_paths
 fn_generate_books_paths "$doc_dir"
 fn_get_book_path
 fn_open_book
fi
exit 0

Here is a link to the repo on github for the ones who would prefer to review it there: https://github.com/yankh764/rdoc

Thanks guys.

Answer 1

Good

• nice indentation
• good docs for the options
• good variable names
• a reasonable amount of inline comments
• yay for being on top of the shellcheck already

Suggestions

• For conditionals it is safer to use double square brackets. Some folks on here discourage the double square brackets for portability, but bash/zsh/ksh all support the more modern syntax.
• Put your config into the format of a script and then source it.
• Put your usage function near the top and include a line that says what the gist of the command is.

Nits

These are minor issues that are more matters of taste.

• I wouldn't proceed every function with the same fn_, but I can see that might make it easier to keep a script of this size straight in your head.
• Putting a space after the hash in a comment will make it easier to read.

• yan_kh: Thank you for such a great review. I was surprised that you also included the good things alongside to the tips and suggestions which is really nice and encouraging, so I appreciate it. Lastly I will of course learn from your tips and modify my script to improve it :)