/42-philosophers

C program that simulates the dining philosophers problem using threads and mutexes.

Primary LanguageC

Philosophers

This is a project called "philo" which simulates the dining philosophers problem using threads and mutexes. It is implemented in the C programming language.

The dining philosophers problem is a classic synchronization problem in computer science, which involves a group of philosophers sitting around a table with a bowl of rice and chopsticks. Each philosopher alternates between thinking and eating. However, there are only a limited number of chopsticks available for the philosophers to share. The challenge is to design an algorithm that allows the philosophers to dine peacefully without getting into a deadlock or starvation situation.

The "philo" project provides a solution to this problem by creating a simulation of the dining philosophers scenario. It utilizes threads to represent each philosopher and mutexes to represent the chopsticks. The program ensures that the philosophers follow a set of rules to avoid deadlocks and provide fairness in resource allocation.

Compilation

To build the project, follow these steps:

  1. Navigate to the project directory:

    cd philo

  2. Build the project using the provided Makefile:

    make

This will compile the source files and generate an executable named philo.

Run

Once you have built the project, you can run it with the following command:

./philo <number_of_philosophers> <time_to_die> <time_to_eat> <time_to_sleep> [number_of_times_each_philosopher_must_eat]
  • <number_of_philosophers>: The number of philosophers sitting around the table.
  • <time_to_die>: The maximum time in milliseconds that a philosopher can survive without eating.
  • <time_to_eat>: The time in milliseconds it takes for a philosopher to finish eating.
  • <time_to_sleep>: The time in milliseconds the philosopher spends sleeping after eating.
  • [number_of_times_each_philosopher_must_eat] (optional): The number of times each philosopher must eat before the simulation ends. If not provided, the simulation will continue indefinitely.

Example usage:

./philo 5 800 200 200

This command will run the simulation with 5 philosophers, a time to die of 800 milliseconds, a time to eat of 200 milliseconds, and a time to sleep of 200 milliseconds. In this example, the simulation will continue indefinitely and any philosopher will die.

Check Data Races

The project cannot have data races, which means it cannot have access to a shared variable between threads without a synchronization mechanism. To check if the project has data races was used the compilation flag -fsanitize=thread. To compile the program with this flag, on the Makefile, remove the # of line 21 and save.

CFLAGS = -Wall -Wextra -Werror -fsanitize=thread

Then compile the project again.

make re

If the program has no data races, the program will run normally. Otherwise, the program will stop and show at the terminal where the error is.

Grade: 100/100

Used tests