classcreator.sh

#!/usr/bin/env sh
# shellcheck disable=SC3043 # local is present in a wide (but not all) number of shells
# so it is almost POSIX to use it but not strictly POSIX

usage(){
	cat <<USAGE
Usage: $name classname [dir] [header_dir class_dir]
Examples:
	-$name classname -> creates a classname.cpp and classname.h class file in the current directory
	-$name classname dir -> creates a dir/classname.cpp and dir/classname.h 
	class file in the specified directory
	-$name classname header_dir class_dir -> creates a header_dir/classname.h and a 
	class_dir/classname.cpp file in the specified directories for header files and source files
USAGE
}

:<<-"GETNAME"
	Function that gets the name of the script that should be used for the printing messages
GETNAME
getname(){
	if echo "$0" | grep -E "^/proc/self/fd" 1>/dev/null;then name="classcreator"
	else name="$(basename -s .sh "$0")"; fi
}

:<<-"SHOULD_DELETE"
	Function that checks whever or not a user wants to delete an already existing file
	This function exits the script if the user doesn't want to delete the file
SHOULD_DELETE
should_delete(){
	read -p "File $1 already exists. Proceed to deletion ?[y/n]
$> " user_answer
	if [ "$user_answer" == 'y' ] ; then return 0 ; fi
	echo "Not proceeding with script execution"
	kill -INT $$
}

:<<-CREATE_FILE
	Function that creates a file with the given filename as an input. If no file is provided, do nothing
	If the file can't be created, return an error
CREATE_FILE
create_file(){
	if [ "$1" = "" ] ; then return 1; fi
	if [ -f "$1" ] && should_delete "$1" ; then shred -f -n 10 -u -z "$1" ; fi
	if [ ! -d "$(dirname "$1")" ] ; then mkdir -p "$(dirname "$1")" ; fi
	if ! touch "$1" ; then echo "Couldn't create file : $1"; return 1 ; fi
	return 0;
}

:<<-"ADD_SLASH_DIR"
	Function that adds a trailing '/' if needed to a directory name
ADD_SLASH_DIR
add_slash_dir(){
	local tmp

	tmp="$(echo "$dir" | rev)"
	if [ "$(echo "$tmp" | cut -c 1-1)" = "/" ] ; then return 0 ; fi
	dir="${dir}/"
	return 0
}

:<<-"GETPATHS"
	Function that gets the paths to the class header file and to the class source
	According to the arguments that were provided to the script
GETPATHS
getpaths(){
	local dir

	if [ "$2" = "" ] ; then class_header="$1".h ; class_source="$1".cpp; return 0; fi
	dir="$2"
	add_slash_dir
	if [ "$3" = "" ] ; then class_header="${dir}${1}.h" ; class_source="${dir}${1}.cpp"; return 0; fi
	class_header="${dir}${1}.h"
	dir="$3"
	add_slash_dir
	class_source="${dir}${1}.cpp"
}


:<<-"CREATE_HEADER"
CREATE_HEADER
create_header(){
	local header
	local upp

	if [ "$2" = "" ] ; then return 1 ; fi
	class="$1"
	header="$2"
	upp="$(echo "$class" | tr '[:lower:]' '[:upper:]')"
	if ! create_file "$header" ; then return 1 ; fi
	cat >"$header" <<HEADER
#ifndef __${upp}_H__
# define __${upp}_H__

class	$class{
	public:
		$class();
		$class( const $class & );
		$class& operator=( const $class & );
		virtual ~$class();
};
#endif
HEADER
	return 0
}

:<<-"CREATE_CLASS"
CREATE_CLASS
create_class(){
	local class
	local classfile

	if [ "$2" = "" ] ; then return 1 ; fi
	class="$1"
	classfile="$2"
	if ! create_file "$classfile" ; then return 1 ; fi
	cat >"$classfile" <<CLASSFILE
#include "${class}.h"

$class::$class(){
}

$class::$class( const $class & other ){
	(void)other;
}

$class&	$class::operator=( const $class & other ){
	(void)other;
	return (*this);
}

$class::~$class(){
}

CLASSFILE
	return 0
}

main(){
	local name
	local class_source
	local class_header

	getname
	if [ "$1" = "" ]
	then
		usage
		return 0
	fi
	getpaths "$@"
	if ! create_header "$1" "$class_header" ; then return 1; fi
	if ! create_class "$1" "$class_source" ; then  return 1; fi
	return 0;
}

main "$@"