phoneBook is contacts handler to save your contacts and mange them easily by friendly command line interface. It is written by Assembly (NASM).

Assembly material is very rare (videos,writeup,errors). No one counter the errors we have, we search a lot without any hope. We find one project talking about phoneBook in assembly but unfortunately it is written by MASM assembly not NASM assembly. Most of project function we write it from scratch without using any external libraries. Most of the project build from scratch and you will not find resources for it in the internet. We put a lot of comments and will try to help you as mush we can to understanding the project. So we hope README will help you in this hard journey. All the functions are dependent in each others and mainly dependent on the correct order of using this function. So listen carefully to README instructions and comments. If you search for phoneBook (MASM) assembly that is not the right place for you. here is resource help you in this journey. GOOD LUCK!

http://www.dailyfreecode.com/Code/phonebook-3542.aspx

If you looking for phoneBook (NASM) Assembly this the right place for you. Welcome!

First, you need to update your system.

sudo apt-get update -y

Then, you need to install NASM to build and run the code. you need to type this command in your terminal (for linux users only)

sudo apt install nasm

you don't need to download the whole repository. You just need to PhoneBook.asm to Build and run the program. However the rest of the repository it is build phases of the program. we build it in phases small functions in small programs. we will leave this small programs for you to learn from it.

you need to type this command in your terminal to download repository.

git clone https://github.com/moramadan98/phoneBook

After you download the repo you need to go to repo directory by the terminal. You can do it by the next command.

cd phoneBook

Now all you need to (Build and run) PhoneBook.asm by the next command (CAUTION! We assume you have already install NASM)

nasm -felf64 PhoneBook.asm && ld PhoneBook.o && ./a.out

Voila! now you have the program running in your terminal.

Intro message when you run the program showing your options in the program and you have to choose.

In this option we add new contact in the program and the program store it in your storage (Don't Worry if the program is close. We store Every thing for you) First we enter the name of the contact (Notice that: maximum name length is 50, If you enter existing name: Contact name is already exist error will appear and if you enter nothing: Invalid input error will appear) then you enter the number (Notice that: maximum number length is 50)

Notice that some files now appear.

Don't worry the program save your contacts by this new files.

In this option we display all contacts you ever add.

In this option we display the contact you search for by typing the whole name. After that the program will display the contact and its numbers (it can be more than one number!). (Notice that: maximum name length is 50, If you enter non existing name: Not found error will appear and if you enter nothing: Invalid input error will appear)

To add new number to exist contact you need to enter this contact name at the first. Then enter the new number. (Notice that: maximum name length is 50,maximum number length is 20, If you enter non existing name: Not found error will appear and if you enter nothing: Invalid input error will appear)

Now search again to see the number.

Voila! now you have 2 numbers in one contact. You can add more without limit.

To remove one number from contact you need to enter this contact name at the first. The program will display all numbers this contact have. You need to type one of them to remove it.

(Notice that: maximum name length is 50,maximum number length is 20, If you enter non existing name: Not found error will appear and if you enter nothing: Invalid input error will appear)

Now search again to see the number.

Done number removed ^_^

To remove one of your contacts you need to enter this contact name.

(Notice that: maximum name length is 50, If you enter non existing name: Not found error will appear and if you enter nothing: Invalid input error will appear)

Now display

As you see we have 2 empty lines here. Why? Because when we delete we leave empty line there. If we have 2 empty lines so we have 2 Deleted contacts.

Delete all contacts

Now let's see what happend to new files in the directory. They gone! also the names inside contact.txt gone too!

If you don't have any choice just exit. Notice that: The program call itself again and again until infinity or you can just write 0 in your choice and program will terminate itself

Contacts appear in file called contacts.txt in phoneBook directory there are empty lines (which we explain before when contact delete it leave empty line in its place)

Every contact has its own file called (name_of_this_contact) and have all numbers of the contact (number by every line) this files appear in phoneBook directory too. notice that: we have one empty line here in numbers too. it is a sign for us to know there was a number in the first line but we delete it. When the number delete it leave empty line in its place just like contacts.

Example: Amr in the next photo.

Because array stores in memory and memory is volatile. So if we use array and we close the program all data we store in array will go away. So we use files to store contacts and numbers of this contacts. Because of that you can add contact, close the program, open the program again, display contacts and you will see you still have your contacts saved because of files technique we use.

Program make "contacts.txt" file if doesn't exist, print option of the program and ask user to choose one of them.

Program will open "contacts.txt" file with read permission. Program ask the user for the name of the contact. Program will use search function to make sure that this name doesn't exist.
If user don't enter name and press enter:
Invalid input error will appear.
If user enter exist name:
Contact name is already exist error will appear.
Else:
Program will open "contacts.txt" file with write permission.
Program will add this name into "contacts.txt" and after add the name he will add empty new line and it will make new file file name will be contact name let's assume it will be "contact_name".

Then, program ask user to enter number for this contact.
If user don't enter number and press enter:
Invalid input error will appear.
Else:
Program will add this number to "contact_name" file (NOTICE: We assume this name earlier), Then add new line.

Program will read "contacts.txt" only and add its contains to buffer in memory. Then, it will loop through the buffer and print names(name/line).

The most confusing part of phoneBook is "Search in contacts" we will try to explain it.

When user choose this option program will read "contacts.txt" only and add its contains to buffer in memory.

The core of search in contacts operation is _Search_String_in_Buffer function. let's deep dive in it!

_Search_String_in_Buffer: (r12 = loadedBuffer, r13 = keyWord, r14 = trimmedString)://r8 = 1/0 Found/Not

    Change: r8,r10,r11,r12,r13,rsi,rdi,rbp,rbx,rcx,rdx,al,bl
    Return: iF Found r8 = 1 , Else r8 = 0       
    mov r12, rsi         ;temp reg to store &trimmedString (will change before its stage) 
    mov r13, rdi        ;temp reg to store &keyWord  (will change before its stage) 

What function do shortly?

This part of function loop through the whole buffer and get start index of contact name and the end index of contact name. How it do that? by search for new line flag ((10) decimal or (A) hex) in the buffer as shown in the previous diagram.

This part of function is take the start index of the name, the end index of the name and copy what between them in another buffer as shown in the previous diagram. now we got the name.

The last part of the function we will compare between the buffer we got from the user and the buffer we got from trim part.

If they equal:
We will print this name and will search for numbers of this contact by find the file hold name of this contact and its contents is contact numbers we will print all of them too.
r8 register will be equal 1

If they not equal:
We will go to part 1 of the function again. Read Char by Char and get start index and end index of the next name.

If function ending and r8 still equal 0 so the name not found. The program will print not found error.

The program will ask user to enter contact name which he want to add number to it, then the program will use search function to find the name.
If user don't enter name and press enter:
Invalid input error will appear.
If user enter name doesn't exist:
Not Found error will appear.
Else:
Program will open new file "contact_name" with write permission (NOTICE: We assume that name earlier) and write the number, then write empty new line. Then, replace the old file with new file.

The program will ask user to enter contact name which he want to delete number from it, then the program will use search function to find the name.
If user don't enter name and press enter:
Invalid input error will appear.
If user enter name doesn't exist:
Not Found error will appear.
Else:
Program will open file "contact_name" for read numbers, display them and ask the user to write the number he want to delete.
If user don't enter number and press enter:
Invalid input error will appear.
If user enter number doesn't exist:
Not Found error will appear.
Program will open new file "contact_name" with write permission (NOTICE: We assume that name earlier) and replace the number with empty (NOTICE: This will the line of the name empty) then replace it with the original file.

The program will ask user to enter contact name which he want to delete it, then the program will use search function to find the name.
If user don't enter name and press enter:
Invalid input error will appear.
If user enter name doesn't exist:
Not Found error will appear.
Else:
Program will open new file "contact.txt" with write permission replace the name with empty (NOTICE: This will the line of the name empty) then replace it with the original file.
Then delete "contact_name" file (NOTICE: We assume that name earlier).

Program will read "contacts.txt" only (If exist) and add its contains to buffer in memory. Then, It will loop through the buffer for every name it found it use Delete contact function.

Program will clear all the buffers and registers. Then, call itself again to start the program again from the beginning (Don't worry all your contacts save in files)

If you don't want this operation then you can simply enter 0: It will close the program without calling itself again,

1- Amr Foaad
2- Muhammad Gamal
3- Mohamed Ramadan
4- Ahmed Hesham Salah
5- Mohamed Mostafa

We have to thank

Prof. Abdelhamid Attaby

And

Eng. Ahmed Bakr

To tech us and give us the knowledge to do something big and complicated like this project. also for helping us walking through the project. So from all my heart THANK YOU!